BACKGROUND OF THE INVENTION ATPases are involved in a variety of metabolic processes (1-4). There is a need in the art to identify related proteins, which can be regulated to provide therapeutic effects.

BRIEF SUMMARY OF THE INVENTION It is an object of the invention to provide reagents and methods of regulating a human cation transporting ATPase. This and other objects of the invention are provided by one or more of the embodiments described below.

One embodiment of the invention is a cation transporting ATPase polypeptide comprising an amino acid sequence selected from the group consisting of : amino acid sequences which are at least about 49% identical to the amino acid sequence shown in SEQ ID NO: 2; and the amino acid sequence shown in SEQ ID NO: 2.

Yet another embodiment of the invention is a method of screening for agents which decrease extracellular matrix degradation. A test compound is contacted with a cation transporting ATPase polypeptide comprising an amino acid sequence selected from the group consisting of :

amino acid sequences which are at least about 49% identical to the amino acid sequence shown in SEQ ID NO: 2; and the amino acid sequence shown in SEQ ID NO: 2.

Binding between the test compound and the cation transporting ATPase polypeptide is detected. A test compound which binds to the cation transporting ATPase polypeptide is thereby identified as a potential agent for decreasing extracellular matrix degradation. The agent can work by decreasing the activity of the cation transporting ATPase.

Another embodiment of the invention is a method of screening for agents which decrease extracellular matrix degradation. A test compound is contacted with a polynucleotide encoding a cation transporting ATPase polypeptide, wherein the polynucleotide comprises a nucleotide sequence selected from the group consisting of : nucleotide sequences which are at least about 50% identical to the nucleotide sequence shown in SEQ ID NO: 1 ; and the nucleotide sequence shown in SEQ ID NO: 1.

Binding of the test compound to the polynucleotide is detected. A test compound which binds to the polynucleotide is identified as a potential agent for decreasing extracellular matrix degradation. The agent can work by decreasing the amount of the cation transporting ATPase through interacting with the cation transporting ATPase mRNA.

Another embodiment of the invention is a method of screening for agents which regulate extracellular matrix degradation. A test compound is contacted with a cation

transporting ATPase polypeptide comprising an amino acid sequence selected from the group consisting of : amino acid sequences which are at least about 49% identical to the amino acid sequence shown in SEQ ID NO: 2; and the amino acid sequence shown in SEQ ID NO: 2.

A cation transporting ATPase activity of the polypeptide is detected. A test compound which increases cation transporting ATPase activity of the polypeptide relative to cation transporting ATPase activity in the absence of the test compound is thereby identified as a potential agent for increasing extracellular matrix degradation.

A test compound which decreases cation transporting ATPase activity of the polypeptide relative to cation transporting ATPase activity in the absence of the test compound is thereby identified as a potential agent for decreasing extracellular matrix degradation.

Even another embodiment of the invention is a method of screening for agents which decrease extracellular matrix degradation. A test compound is contacted with a cation transporting ATPase product of a polynucleotide which comprises a nucleotide sequence selected from the group consisting of : nucleotide sequences which are at least about 50% identical to the nucleotide sequence shown in SEQ ID NO: 1; and the nucleotide sequence shown in SEQ ID NO: 1.

Binding of the test compound to the cation transporting ATPase product is detected.

A test compound which binds to the cation transporting ATPase product is thereby identified as a potential agent for decreasing extracellular matrix degradation.

Still another embodiment of the invention is a method of reducing extracellular matrix degradation. A cell is contacted with a reagent which specifically binds to a polynucleotide encoding a cation transporting ATPase polypeptide or the product encoded by the polynucleotide, wherein the polynucleotide comprises a nucleotide sequence selected from the group consisting of : nucleotide sequences which are at least about 50% identical to the nucleotide sequence shown in SEQ ID NO: 1 ; and the nucleotide sequence shown in SEQ ID NO : 1.

Cation transporting ATPase activity in the cell is thereby decreased.

The invention thus provides a human cation transporting ATPase that can be used to identify test compounds that may act, for example, as activators or inhibitors at the enzyme's active site. Human cation transporting ATPase and fragments thereof also are useful in raising specific antibodies that can block the enzyme and effectively reduce its activity.

BRIEF DESCRIPTION OF THE FIGURES Fig. 1 shows the DNA-sequence encoding a cation transporting ATPase Polypeptide (SEQ ID NO : 1).

Fig. 2 shows the amino acid sequence deduced from the DNA-sequence of Fig. l (SEQ ID NO: 2).

Fig. 3 shows the amino acid sequence of the protein identified by swissnewlQ9NQl llATYl_HUMAN (SEQ ID NO: 3).

Fig. 4 shows the BLASTP-alignment of LBRI_582_protein (SEQ ID NO : 2) against swissnewlQ9NQlllATYl_HUMAN (SEQ ID NO : 3) Probable cation-transporting ATPase (EC 3.6. 1.-).//: trembllAL354615lHS37Cl03_ 1 product:"hypothetical protein" ; Novel human gene mapping to chromosome I H : gpiAL35461517688148 product:"hypothetical protein" ; Novel human gene mapping to chromosome 1. This hit is scoring at: 0.0 (expectation value). Alignment length (overlap): 735, Identities: 48 %, Scoring matrix : BLOSUM62 (used to infer consensus pattern), Database searched: nrdb_l_.

Fig. 5 shows the Predicted transmembrane domains.

Fig. 6 shows the Alignments of top-scoring domains.

Fig. 7 shows the BLASTX-alignment of LBRI 582 DNA against pdblIEUL11EUL-A (swissIP117191ATCB-RABIT) CALCIUM-TRANSPO R- TING ATPASE SARCOPLASMIC RETICULUM TYPE, FAST TWITCH SKELETAL MUSCLE, ADULT ISOFORM (EC 3.6. 1. 38) (CALCIUM PUMP) (SERCA1). This hit is scoring at : 3e-20 (expectation value).

Alignment length (overlap): 705, Identities : 22 %, Scoring matrix : BLOSUM62 (used to infer consensus pattern), Query reading frame: +1, Database searched: nrdb l.

Fig. 8 shows the Genewise output. Score 1434.43 bits over entire alignment.

Scores as bits over a synchronous coding model.

Fig. 9 shows the DNA-sequence encoding a cation transporting ATPase Polypeptide.

Fig. 10 shows the amino acid sequence deduced from the DNA-sequence of Fig. 9.

DETAILED DESCRIPTION OF THE INVENTION The invention relates to an isolated polynucleotide from the group consisting of : a) a polynucleotide encoding a cation transporting ATPase polypeptide comprising an amino acid sequence selected from the group consisting of : i) amino acid sequences which are at least about 49% identical to the amino acid sequence shown in SEQ ID NO: 2; and ii) the amino acid sequence shown in SEQ ID NO: 2; b) a polynucleotide comprising the sequence of SEQ ID NO: 1; c) a polynucleotide which hybridizes under stringent conditions to a polynucleotide specified in (a) and (b) and encodes a cation transporting ATPase polypeptide; d) a polynucleotide the sequence of which deviates from the polynucleotide sequences specified in (a) to (c) due to the degeneration of the genetic code and encodes a cation transporting ATPase polypeptide; and e) a polynucleotide which represents a fragment, derivative or allelic variation of a polynucleotide sequence specified in (a) to (d) and encodes a cation transporting ATPase polypeptide.

Furthermore, it has been discovered by the present applicant that a novel cation transporting ATPase, particularly a human cation transporting ATPase, can be used in therapeutic methods to treat a respiratory or thyroid disorder. Human cation transporting ATPase comprises the amino acid sequence shown in SEQ ID NO: 2. A coding sequence for human cation transporting ATPase is shown in SEQ ID NO: 1.

This sequence is located on chromosome 3. Related ESTs (BE154453; BF362216; AW438507; BE169749) are expressed in human head neck cells, nervous normal cells, and normal squamous epithelium from retromolar trigone, in pig pooled tissue (testis, ovary, endometrium, hypothalamus, pituitary, and placenta), and in mouse brain. Expression profiling, on the other hand, shows high expression in the human lung and thyroid.

The functional annotation of SEQ ID NO: 2 as a catp-like protein rests on the Pfam hits with the two motifs always associated with the catp family of proteins--the El- E2 ATPase or P-type domain, PF00122, and the haloacid dehalogenase-like hydrolase domain, PF00702. The pfam scores and expect values for the E1-E2 ATPase domain and the haloacid dehalogenase-like hydrolase domain were 32.5 Expect 3.9e-10 and 12.4 Expect 0.001, respectively. These scores and expect values support the functional annotation of SEQ ID NO: 2 as a catp-like protein. In addition, Prosite analysis identifies the E1-E2 ATPase phosphorylation site. All catp-like proteins share this motif, which is underlined and in bold in FIG. 1. Additionally, the 3D structure is inferred by clear homology to the rabbit sarcoplasmic reticulum type Ca++-transporting ATPase from residues 267 to 738. However, phylogenetic analysis built from Psi-BLAST results suggests that SEQ ID NO: 2 shares greater similarity to Na+/K+ ATPases. Based on various transmembrane domain prediction programs, SEQ ID NO: 2 has between four and five transmembrane domains. All catps have multiple transmembrane domains, usually between eight and twelve. EST and expression profiling data suggests this target is functionally expressed. Two of the ESTs that share very high identity with the coding sequence for SEQ ID NO: 2 contain different inframe stop-codons; however, the genomic data and ESTs from other species do not support the assignment of a stop-codon.

Human cation transporting ATPase is believed to be useful in therapeutic methods to treat respiratory disorders including but not limited to asthma, thyroid, and urological disorders. Human cation transporting ATPase also can be used to screen for human cation transporting ATPase activators and inhibitors.

Polypeptides Human cation transporting ATPase polypeptides according to the invention comprise at least 6,10, 15,20, 25,50, 75,100, 125,150, 175,200, 225,250, 275,300, 350, 400,450, 500,550, 600,650, 700,750, 800 or 831 contiguous amino acids selected from the amino acid sequence shown in SEQ ID NO: 2 or a biologically active variant thereof, as defined below. A cation transporting ATPase polypeptide of the invention therefore can be a portion of a cation transporting ATPase protein, a full- length cation transporting ATPase protein, or a fusion protein comprising all or a portion of a cation transporting ATPase protein.

Biologically active variants Human cation transporting ATPase polypeptide variants that are biologically active, e. g., retain an enzymatic activity, also are cation transporting ATPase polypeptides.

Preferably, naturally or non-naturally occurring cation transporting ATPase polypeptide variants have amino acid sequences which are at least about 49,50, 55, 60,65, or 70, preferably about 75,80, 85,90, 96,96, 98, or 99% identical to the amino acid sequence shown in SEQ ID NO: 2 or a fragment thereof. Percent identity between a putative cation transporting ATPase polypeptide variant and an amino acid sequence of SEQ ID NO: 2 is determined by conventional methods. See, for example, Altschul et al., Bull. Math. Bio. 48: 603 (1986), and Henikoff & Henikoff, Proc. Natl. Acad. Sci. USA 89: 10915 (1992). Briefly, two amino acid sequences are aligned to optimize the alignment scores using a gap opening penalty of 10, a gap extension penalty of 1, and the"BLOSUM62"scoring matrix of Henikoff & Henikoff, 1992.

Those skilled in the art appreciate that there are many established algorithms available to align two amino acid sequences. The"FASTA"similarity search algorithm of Pearson & Lipman is a suitable protein alignment method for examining the level of identity shared by an amino acid sequence disclosed herein and the amino acid sequence of a putative variant. The FASTA algorithm is described by Pearson

& Lipman, Proc. Nat'1 Acad. Sci. USA 85: 2444 (1988), and by Pearson, Meth.

Enzymol. 183: 63 (1990). Briefly, FASTA first characterizes sequence similarity by identifying regions shared by the query sequence (e. g., SEQ ID NO : 2) and a test sequence that have either the highest density of identities (if the ktup variable is 1) or pairs of identities (if ktup=2), without considering conservative amino acid substitutions, insertions, or deletions. The ten regions with the highest density of identities are then rescored by comparing the similarity of all paired amino acids using an amino acid substitution matrix, and the ends of the regions are"trimmed" to include only those residues that contribute to the highest score. If there are several regions with scores greater than the"cutoff'value (calculated by a predetermined formula based upon the length of the sequence the ktup value), then the trimmed initial regions are examined to determine whether the regions can be joined to form an approximate alignment with gaps. Finally, the highest scoring regions of the two amino acid sequences are aligned using a modification of the Needleman-Wunsch- Sellers algorithm (Needleman & Wunsch, J. Mol. Biol. 48: 444 (1970); Sellers, SIAM <BR> <BR> J. Appl. Math. 26: 787 (1974) ), which allows for amino acid insertions and deletions.

Preferred parameters for FASTA analysis are : ktup=l, gap opening penalty=10, gap extension penalty=l, and substitution matrix=BLOSUM62. These parameters can be introduced into a FASTA program by modifying the scoring matrix file ("SMATRIX"), as explained in Appendix 2 of Pearson, Meth. Enzymol. 183: 63 (1990).

FASTA can also be used to determine the sequence identity of nucleic acid molecules using a ratio as disclosed above. For nucleotide sequence comparisons, the ktup value can range between one to six, preferably from three to six, most preferably three, with other parameters set as default.

Variations in percent identity can be due, for example, to amino acid substitutions, insertions, or deletions. Amino acid substitutions are defined as one for one amino acid replacements. They are conservative in nature when the substituted amino acid has similar structural and/or chemical properties. Examples of conservative

replacements are substitution of a leucine with an isoleucine or valine, an aspartate with a glutamate, or a threonine with a serine.

Amino acid insertions or deletions are changes to or within an amino acid sequence.

They typically fall in the range of about 1 to 5 amino acids. Guidance in determining which amino acid residues can be substituted, inserted, or deleted without abolishing biological or immunological activity of a human cation transporting ATPase polypeptide can be found using computer programs well known in the art, such as DNASTAR software.

The invention additionally, encompasses cation transporting ATPase polypeptides <BR> <BR> that are differentially modified during or after translation, e. g. , by glycosylation, acetylation, phosphorylation, amidation, derivatization by known protecting/blocking groups, proteolytic cleavage, linkage to an antibody molecule or other cellular ligand, etc. Any of numerous chemical modifications can be carried out by known techniques including, but not limited, to specific chemical cleavage by cyanogen bromide, trypsin, chymotrypsin, papain, V8 protease, NaBH4, acetylation, formylation, oxidation, reduction, metabolic synthesis in the presence of tunicamycin, etc.

Additional post-translational modifications encompassed by the invention include, <BR> <BR> for example, e. g. , N-linked or 0-linked carbohydrate chains, processing of N- terminal or C-terminal ends), attachment of chemical moieties to the amino acid backbone, chemical modifications of N-linked or 0-linked carbohydrate chains, and addition or deletion of an N-terminal methionine residue as a result of prokaryotic host cell expression. The cation transporting ATPase polypeptides may also be modified with a detectable label, such as an enzymatic, fluorescent, isotopic or affinity label to allow for detection and isolation of the protein.

The invention also provides chemically modified derivatives of cation transporting ATPase polypeptides that may provide additional advantages such as increased

solubility, stability and circulating time of the polypeptide, or decreased immunogenicity (see U. S. Patent No. 4,179, 337). The chemical moieties for derivitization can be selected from water soluble polymers such as polyethylene glycol, ethylene glycol/propylene glycol copolymers, carboxymethylcellulose, dextran, polyvinyl alcohol, and the like. The polypeptides can be modified at random or predetermined positions within the molecule and can include one, two, three, or more attached chemical moieties.

Whether an amino acid change or a polypeptide modification results in a biologically active cation transporting ATPase polypeptide can readily be determined by assaying for enzymatic activity, as described for example, in J Biochem Mol Toxicol 1999 ; 13 (2): 93-106.

Fusion proteins Fusion proteins are useful for generating antibodies against cation transporting ATPase polypeptide amino acid sequences and for use in various assay systems. For example, fusion proteins can be used to identify proteins that interact with portions of a human cation transporting ATPase polypeptide. Protein affinity chromatography or library-based assays for protein-protein interactions, such as the yeast two-hybrid or phage display systems, can be used for this purpose. Such methods are well known in the art and also can be used as drug screens.

A human cation transporting ATPase polypeptide fusion protein comprises two polypeptide segments fused together by means of a peptide bond. The first polypeptide segment comprises at least 6,10, 15,20, 25,50, 75,100, 125,150, 175, 200,225, 250,275, 300,350, 400,450, 500,550, 600, 650, 700, 750, 800 or 831 contiguous amino acids of SEQ ID NO: 2 or of a biologically active variant, such as those described above. The first polypeptide segment also can comprise full-length cation transporting ATPase protein.

The second polypeptide segment can be a full-length protein or a protein fragment.

Proteins commonly used in fusion protein construction include ß-galactosidase, p- glucuronidase, green fluorescent protein (GFP), autofluorescent proteins, including blue fluorescent protein (BFP), glutathione-S-transferase (GST), luciferase, horseradish peroxidase (HRP), and chloramphenicol acetyltransferase (CAT).

Additionally, epitope tags are used in fusion protein constructions, including histidine (His) tags, FLAG tags, influenza hemagglutinin (HA) tags, Myc tags, VSV- G tags, and thioredoxin (Trx) tags. Other fusion constructions can include maltose binding protein (MBP), S-tag, Lex a DNA binding domain (DBD) fusions, GAL4 DNA binding domain fusions, and herpes simplex virus (HSV) BP 16 protein fusions.

A fusion protein also can be engineered to contain a cleavage site located between the cation transporting ATPase polypeptide-encoding sequence and the heterologous protein sequence, so that the cation transporting ATPase polypeptide can be cleaved and purified away from the heterologous moiety.

A fusion protein can be synthesized chemically, as is known in the art. Preferably, a fusion protein is produced by covalently linking two polypeptide segments or by standard procedures in the art of molecular biology. Recombinant DNA methods can be used to prepare fusion proteins, for example, by making a DNA construct which comprises coding sequences selected from SEQ ID NO: 1 in proper reading frame with nucleotides encoding the second polypeptide segment and expressing the DNA construct in a host cell, as is known in the art. Many kits for constructing fusion proteins are available from companies such as Promega Corporation (Madison, WI), Stratagene (La Jolla, CA), CLONTECH (Mountain View, CA), Santa Cruz Biotechnology (Santa Cruz, CA), MBL International Corporation (MIC; Watertown, MA), and Quantum Biotechnologies (Montreal, Canada; 1-888-DNA- KITS).

Identification of species homologs Species homologs of human cation transporting ATPase polypeptide can be obtained using cation transporting ATPase polypeptide polynucleotides (described below) to

make suitable probes or primers for screening cDNA expression libraries from other species, such as mice, monkeys, or yeast, identifying cDNAs which encode homologs of cation transporting ATPase polypeptide, and expressing the cDNAs as is known in the art.

Polynucleotides A human cation transporting ATPase polynucleotide can be single-or double- stranded and comprises a coding sequence or the complement of a coding sequence for a cation transporting ATPase polypeptide. A coding sequence for human cation transporting ATPase is shown in SEQ ID NO: 1.

Degenerate nucleotide sequences encoding human cation transporting ATPase polypeptides, as well as homologous nucleotide sequences which are at least about 50,55, 60,65, 70, preferably about 75,90, 96,98, or 99% identical to the nucleotide sequence shown in SEQ ID NO: 1 or its complement also are cation transporting ATPase polynucleotides. Percent sequence identity between the sequences of two polynucleotides is determined using computer programs such as ALIGN which employ the FASTA algorithm, using an affine gap search with a gap open penalty of - 12 and a gap extension penalty of-2. Complementary DNA (cDNA) molecules, species homologs, and variants of cation transporting ATPase polynucleotides that encode biologically active cation transporting ATPase polypeptides also are cation transporting ATPase polynucleotides. Polynucleotide fragments comprising at least 8,9, 10,11, 12,15, 20, or 25 contiguous nucleotides of SEQ ID NO: 1 or its complement also are cation transporting ATPase polynucleotides. These fragments can be used, for example, as hybridization probes or as antisense oligonucleotides.

Identification of polynucleotide variants and homologs Variants and homologs of the cation transporting ATPase polynucleotides described above also are cation transporting ATPase polynucleotides. Typically, homologous cation transporting ATPase polynucleotide sequences can be identified by hybridization of candidate polynucleotides to known cation transporting ATPase

polynucleotides under stringent conditions, as is known in the art. For example, using the following wash conditions--2X SSC (0.3 M NaCl, 0.03 M sodium citrate, pH 7.0), 0.1% SDS, room temperature twice, 30 minutes each; then 2X SSC, 0.1% SDS, 50 °C once, 30 minutes; then 2X SSC, room temperature twice, 10 minutes each--homologous sequences can be identified which contain at most about 25-30% basepair mismatches. More preferably, homologous nucleic acid strands contain 15-25% basepair mismatches, even more preferably 5-15% basepair mismatches.

Species homologs of the cation transporting ATPase polynucleotides disclosed herein also can be identified by making suitable probes or primers and screening cDNA expression libraries from other species, such as mice, monkeys, or yeast. Human variants of cation transporting ATPase polynucleotides can be identified, for example, by screening human cDNA expression libraries. It is well known that the Tm of a double-stranded DNA decreases by 1-1. 5 °C with every 1% decrease in homology (Bonner et al., J. Mol. Biol. 81, 123 (1973). Variants of human cation transporting ATPase polynucleotides or cation transporting ATPase polynucleotides of other species can therefore be identified by hybridizing a putative homologous cation transporting ATPase polynucleotide with a polynucleotide having a nucleotide sequence of SEQ ID NO: 1 or the complement thereof to form a test hybrid. The melting temperature of the test hybrid is compared with the melting temperature of a hybrid comprising polynucleotides having perfectly complementary nucleotide sequences, and the number or percent of basepair mismatches within the test hybrid is calculated.

Nucleotide sequences which hybridize to cation transporting ATPase polynucleotides or their complements following stringent hybridization and/or wash conditions also are cation transporting ATPase polynucleotides. Stringent wash conditions are well known and understood in the art and are disclosed, for example, in Sambrook et al., MOLECULAR CLONING: A LABORATORY MANUAL, 2d ed., 1989, at pages 9.50-9. 51.

Typically, for stringent hybridization conditions a combination of temperature and salt concentration should be chosen that is approximately 12-20°C below the calculated Tm of the hybrid under study. The Tm of a hybrid between a cation transporting ATPase polynucleotide having a nucleotide sequence shown in SEQ ID NO: 1 or the complement thereof and a polynucleotide sequence which is at least about 50, preferably about 75,90, 96, or 98% identical to one of those nucleotide sequences can be calculated, for example, using the equation of Bolton and McCarthy, Proc. Natl. Acad. Sci. U. S. A. 48, 1390 (1962): Tm = 81. 5 °C-16. 6 (logio [Na+]) + 0.41 (% G + C) -0. 63 (% formamide) - 600/), where l = the length of the hybrid in basepairs.

Stringent wash conditions include, for example, 4X SSC at 65°C, or 50% formamide, 4X SSC at 42°C, or 0. 5X SSC, 0.1% SDS at 65 °C. Highly stringent wash conditions include, for example, 0.2X SSC at 65 °C.

Preparation of polynucleotides A human cation transporting ATPase polynucleotide can be isolated free of other cellular components such as membrane components, proteins, and lipids.

Polynucleotides can be made by a cell and isolated using standard nucleic acid purification techniques, or synthesized using an amplification technique, such as the polymerase chain reaction (PCR), or by using an automatic synthesizer. Methods for isolating polynucleotides are routine and are known in the art. Any such technique for obtaining a polynucleotide can be used to obtain isolated cation transporting ATPase polynucleotides. For example, restriction enzymes and probes can be used to isolate polynucleotide fragments, which comprise cation transporting ATPase nucleotide sequences. Isolated polynucleotides are in preparations that are free or at least 70,80, or 90% free of other molecules.

Human cation transporting ATPase cDNA molecules can be made with standard molecular biology techniques, using cation transporting ATPase mRNA as a

template. Human cation transporting ATPase cDNA molecules can thereafter be replicated using molecular biology techniques known in the art and disclosed in manuals such as Sambrook et al. (1989). An amplification technique, such as PCR, can be used to obtain additional copies of polynucleotides of the invention, using either human genomic DNA or cDNA as a template.

Alternatively, synthetic chemistry techniques can be used to synthesize cation transporting ATPase polynucleotides. The degeneracy of the genetic code allows alternate nucleotide sequences to be synthesized which will encode a human cation transporting ATPase polypeptide having, for example, an amino acid sequence shown in SEQ ID NO: 2 or a biologically active variant thereof.

Extending polynucleotides The partial sequence disclosed herein can be used to identify the corresponding full- length gene from which it was derived. The partial sequence can be nick-translated or end-labeled with 32P using polynucleotide kinase using labeling methods known to those with skill in the art (Basic Methods in Molecular Biology, Davis et al. , eds.,<BR> Elsevier Press, N. Y. , 1986). A lambda library prepared from human tissue can be directly screened with the labeled sequences of interest or the library can be converted en masse to pBluescript (Stratagene Cloning Systems, La Jolla, Calif.

92037) to facilitate bacterial colony screening (see Sambrook et al., Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press (1989, pg.

1. 20).

Both methods are well known in the art. Briefly, filters with bacterial colonies containing the library in pBluescript or bacterial lawns containing lambda plaques are denatured, and the DNA is fixed to the filters. The filters are hybridized with the labeled probe using hybridization conditions described by Davis et al. , 1986. The partial sequences, cloned into lambda or pBluescript, can be used as positive controls to assess background binding and to adjust the hybridization and washing stringencies necessary for accurate clone identification. The resulting autoradiograms

are compared to duplicate plates of colonies or plaques ; each exposed spot corresponds to a positive colony or plaque. The colonies or plaques are selected, expanded and the DNA is isolated from the colonies for further analysis and sequencing.

Positive cDNA clones are analyzed to determine the amount of additional sequence they contain using PCR with one primer from the partial sequence and the other primer from the vector. Clones with a larger vector-insert PCR product than the original partial sequence are analyzed by restriction digestion and DNA sequencing to determine whether they contain an insert of the same size or similar as the mRNA size determined from Northern blot Analysis.

Once one or more overlapping cDNA clones are identified, the complete sequence of the clones can be determined, for example after exonuclease III digestion (McCombie et al., Methods 3,33-40, 1991). A series of deletion clones are generated, each of which is sequenced. The resulting overlapping sequences are assembled into a single contiguous sequence of high redundancy (usually three to five overlapping sequences at each nucleotide position), resulting in a highly accurate final sequence.

Various PCR-based methods can be used to extend the nucleic acid sequences disclosed herein to detect upstream sequences such as promoters and regulatory elements. For example, restriction-site PCR uses universal primers to retrieve unknown sequence adjacent to a known locus (Sarkar, PCR Methods Applic. 2, 318-322,1993). Genomic DNA is first amplified in the presence of a primer to a linker sequence and a primer specific to the known region. The amplified sequences are then subjected to a second round of PCR with the same linker primer and another specific primer internal to the first one. Products of each round of PCR are transcribed with an appropriate RNA polymerase and sequenced using reverse transcriptase.

Inverse PCR also can be used to amplify or extend sequences using divergent primers based on a known region (Triglia et al., Nucleic Acids Res. 16,8186, 1988). Primers can be designed using commercially available software, such as OLIGO 4. 06 Primer Analysis software (National Biosciences Inc. , Plymouth, Minn. ), to be 22-30 nucleotides in length, to have a GC content of 50% or more, and to anneal to the target sequence at temperatures about 68-72°C. The method uses several restriction enzymes to generate a suitable fragment in the known region of a gene. The fragment is then circularized by intramolecular ligation and used as a PCR template.

Another method which can be used is capture PCR, which involves PCR amplification of DNA fragments adjacent to a known sequence in human and yeast artificial chromosome DNA (Lagerstrom et al. , PCR Methods Applic. 1, 111-119, 1991). In this method, multiple restriction enzyme digestions and ligations also can be used to place an engineered double-stranded sequence into an unknown fragment of the DNA molecule before performing PCR.

Another method which can be used to retrieve unknown sequences is that of Parker et al., Nucleic Acids Res. 19,3055-3060, 1991). Additionally, PCR, nested primers, and PROMOTERFINDER libraries (CLONTECH, Palo Alto, Calif. ) can be used to<BR> walk genomic DNA (CLONTECH, Palo Alto, Calif. ). This process avoids the need to screen libraries and is useful in finding intron/exon junctions.

When screening for full-length cDNAs, it is preferable to use libraries that have been size-selected to include larger cDNAs. Randomly-primed libraries are preferable, in' that they will contain more sequences which contain the 5'regions of genes. Use of a randomly primed library may be especially preferable for situations in which an oligo d (T) library does not yield a full-length cDNA. Genomic libraries can be useful for extension of sequence into 5'non-transcribed regulatory regions.

Commercially available capillary electrophoresis systems can be used to analyze the size or confirm the nucleotide sequence of PCR or sequencing products. For

example, capillary sequencing can employ flowable polymers for electrophoretic separation, four different fluorescent dyes (one for each nucleotide) that are laser activated, and detection of the emitted wavelengths by a charge coupled device camera. Output/light intensity can be converted to electrical signal using appropriate software (e. g. GENOTYPER and Sequence NAVIGATOR, Perkin Elmer), and the entire process from loading of samples to computer analysis and electronic data display can be computer controlled. Capillary electrophoresis is especially preferable for the sequencing of small pieces of DNA that might be present in limited amounts in a particular sample.

Obtaining Polynucleotides Human cation transporting ATPase polypeptides can be obtained, for example, by purification from human cells, by expression of cation transporting ATPase polynucleotides, or by direct chemical synthesis.

Protein purification Human cation transporting ATPase polypeptides can be purified from any human cell which expresses the receptor, including host cells which have been transfected with cation transporting ATPase polynucleotides. A purified cation transporting ATPase polypeptide is separated from other compounds that normally associate with the cation transporting ATPase polypeptide in the cell, such as certain proteins, carbohydrates, or lipids, using methods well-known in the art. Such methods include, but are not limited to, size exclusion chromatography, ammonium sulfate fractionation, ion exchange chromatography, affinity chromatography, and preparative gel electrophoresis.

Human cation transporting ATPase polypeptide can be conveniently isolated as a complex with its associated G protein, as described in the specific examples, below.

A preparation of purified cation transporting ATPase polypeptides is at least 80% pure; preferably, the preparations are 90%, 95%, or 99% pure. Purity of the

preparations can be assessed by any means known in the art, such as SDS- polyacrylamide gel electrophoresis.

Expression of polynucleotides To express a human cation transporting ATPase polynucleotide, the polynucleotide can be inserted into an expression vector which contains the necessary elements for the transcription and translation of the inserted coding sequence. Methods which are well known to those skilled in the art can be used to construct expression vectors containing sequences encoding cation transporting ATPase polypeptides and appropriate transcriptional and translational control elements. These methods include in vitro recombinant DNA techniques, synthetic techniques, and in vivo genetic recombination. Such techniques are described, for example, in Sambrook et al. (1989) and in Ausubel et al., CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, John Wiley & Sons, New York, N. Y. , 1989.

A variety of expression vector/host systems can be utilized to contain and express sequences encoding a human cation transporting ATPase polypeptide. These include, but are not limited to, microorganisms, such as bacteria transformed with recombinant bacteriophage, plasmid, or cosmid DNA expression vectors; yeast transformed with yeast expression vectors, insect cell systems infected with virus expression vectors (e. g., baculovirus), plant cell systems transformed with virus expression vectors (e. g., cauliflower mosaic virus, CaMV ; tobacco mosaic virus, <BR> <BR> TMV) or with bacterial expression vectors (e. g. , Ti or pBR322 plasmids), or animal cell systems.

The control elements or regulatory sequences are those non-translated regions of the vector--enhancers, promoters, 5'and 3'untranslated regions--which interact with host cellular proteins to carry out transcription and translation. Such elements can vary in their strength and specificity. Depending on the vector system and host utilized, any number of suitable transcription and translation elements, including constitutive and inducible promoters, can be used. For example, when cloning in

bacterial systems, inducible promoters such as the hybrid lacZ promoter of the BLUESCRIPT phagemid (Stratagene, LaJolla, Calif.) or pSPORTl plasmid (Life Technologies) and the like can be used. The baculovirus polyhedrin promoter can be used in insect cells. Promoters or enhancers derived from the genomes of plant cells (e. g., heat shock, RUBISCO, and storage protein genes) or from plant viruses (e. g., viral promoters or leader sequences) can be cloned into the vector. In mammalian cell systems, promoters from mammalian genes or from mammalian viruses are preferable. If it is necessary to generate a cell line that contains multiple copies of a nucleotide sequence encoding a human cation transporting ATPase polypeptide, vectors based on SV40 or EBV can be used with an appropriate selectable marker.

Bacterial and yeast expression systems In bacterial systems, a number of expression vectors can be selected depending upon the use intended for the cation transporting ATPase polypeptide. For example, when a large quantity of a human cation transporting ATPase polypeptide is needed for the induction of antibodies, vectors which direct high level expression of fusion proteins that are readily purified can be used. Such vectors include, but are not limited to, multifunctional E. coli cloning and expression vectors such as BLUESCRIPT (Stratagene). In a BLUESCRIPT vector, a sequence encoding the cation transporting ATPase polypeptide can be ligated into the vector in frame with sequences for the amino-terminal Met and the subsequent 7 residues of p-galactosidase so that a hybrid protein is produced. pIN vectors (Van Heeke & Schuster, J. Biol. Chem. 264,5503-5509, 1989) or pGEX vectors (Promega, Madison, Wis. ) also can be used to express foreign polypeptides as fusion proteins with glutathione S-transferase (GST). In general, such fusion proteins are soluble and can easily be purified from lysed cells by adsorption to glutathione-agarose beads followed by elution in the presence of free glutathione. Proteins made in such systems can be designed to include heparin, thrombin, or factor Xa protease cleavage sites so that the cloned polypeptide of interest can be released from the GST moiety at will.

In the yeast Saccharomyces cerevisiae, a number of vectors containing constitutive or inducible promoters such as alpha factor, alcohol oxidase, and PGH can be used. For reviews, see Ausubel et al. (1989) and Grant et al., Methods Enzymol. 153, 516-544, 1987.

Plant and insect expression systems If plant expression vectors are used, the expression of sequences encoding cation transporting ATPase polypeptides can be driven by any of a number of promoters.

For example, viral promoters such as the 35S and 19S promoters of CaMV can be used alone or in combination with the omega leader sequence from TMV (Takamatsu, EMBO J. 6, 307-311, 1987). Alternatively, plant promoters such as the small subunit of RUBISCO or heat shock promoters can be used (Coruzzi et al., EMBO J. 3, 1671-1680, 1984; Broglie et al., Science 224, 838-843, 1984; Winter et <BR> <BR> al. , Results Probl. Cell Differ. 17,85-105, 1991). These constructs can be introduced into plant cells by direct DNA transformation or by pathogen-mediated transfection.

Such techniques are described in a number of generally available reviews (e. g., Hobbs or Murray, in McGraw Hill Yearbook of Science and Technology, McGraw Hill, New York, N. Y. , pp. 191-196, 1992).

An insect system also can be used to express a human cation transporting ATPase polypeptide. For example, in one such system Autographa californica nuclear polyhedrosis virus (AcNPV) is used as a vector to express foreign genes in Spodoptera frugiperda cells or in Trichoplusia larvae. Sequences encoding cation transporting ATPase polypeptides can be cloned into a non-essential region of the virus, such as the polyhedrin gene, and placed under control of the polyhedrin promoter. Successful insertion of cation transporting ATPase polypeptides will render the polyhedrin gene inactive and produce recombinant virus lacking coat protein. The recombinant viruses can then be used to infect S. frugiperda cells or Trichoplusia larvae in which cation transporting ATPase polypeptides can be expressed (Engelhard et al. , Proc. Nat. Acad. Sci. 91, 3224-3227, 1994).

Mammalian expression systems A number of viral-based expression systems can be used to express cation transporting ATPase polypeptides in mammalian host cells. For example, if an adenovirus is used as an expression vector, sequences encoding cation transporting ATPase polypeptides can be ligated into an adenovirus transcription/translation complex comprising the late promoter and tripartite leader sequence. Insertion in a non-essential El or E3 region of the viral genome can be used to obtain a viable virus which is capable of expressing a human cation transporting ATPase polypeptide in infected host cells (Logan & Shenk, Proc. Natl. Acad. Sci. 81,3655-3659, 1984). If desired, transcription enhancers, such as the Rous sarcoma virus (RSV) enhancer, can be used to increase expression in mammalian host cells.

Human artificial chromosomes (HACs) also can be used to deliver larger fragments of DNA than can be contained and expressed in a plasmid. HACs of 6M to 1 OM are constructed and delivered to cells via conventional delivery methods (e. g. , liposomes, polycationic amino polymers, or vesicles).

Specific initiation signals also can be used to achieve more efficient translation of sequences encoding cation transporting ATPase polypeptides. Such signals include the ATG initiation codon and adjacent sequences. In cases where sequences encoding a human cation transporting ATPase polypeptide, its initiation codon, and upstream sequences are inserted into the appropriate expression vector, no additional transcriptional or translational control signals may be needed. However, in cases where only coding sequence, or a fragment thereof, is inserted, exogenous translational control signals (including the ATG initiation codon) should be provided.

The initiation codon should be in the correct reading frame to ensure translation of the entire insert. Exogenous translational elements and initiation codons can be of various origins, both natural and synthetic. The efficiency of expression can be enhanced by the inclusion of enhancers which are appropriate for the particular cell system which is used (see Scharf et al., Results Probl. Cell Differ. 20,125-162, 1994).

Host cells A host cell strain can be chosen for its ability to modulate the expression of the inserted sequences or to process the expressed cation transporting ATPase polypeptide in the desired fashion. Such modifications of the polypeptide include, but are not limited to, acetylation, carboxylation, glycosylation, phosphorylation, lipidation, and acylation. Post-translational processing which cleaves a"prepro" form of the polypeptide also can be used to facilitate correct insertion, folding and/or function. Different host cells that have specific cellular machinery and characteristic mechanisms for post-translational activities (e. g. , CHO, HeLa, MDCK, HEK293, and WI38), are available from the American Type Culture Collection (ATCC; 10801 University Boulevard, Manassas, VA 20110-2209) and can be chosen to ensure the correct modification and processing of the foreign protein.

Stable expression is preferred for long-term, high-yield production of recombinant proteins. For example, cell lines which stably express cation transporting ATPase polypeptides can be transformed using expression vectors which can contain viral origins of replication and/or endogenous expression elements and a selectable marker gene on the same or on a separate vector. Following the introduction of the vector, cells can be allowed to grow for 1-2 days in an enriched medium before they are switched to a selective medium. The purpose of the selectable marker is to confer resistance to selection, and its presence allows growth and recovery of cells which successfully express the introduced cation transporting ATPase sequences. Resistant clones of stably transformed cells can be proliferated using tissue culture techniques appropriate to the cell type. See, for example, Animal Cell Culture, R. I. Freshney, ed. , 1986.

Any number of selection systems can be used to recover transformed cell lines.

These include, but are not limited to, the herpes simplex virus thymidine kinase (Wigler et al., Cell 11,223-32, 1977) and adenine phosphoribosyltransferase (Lowy <BR> <BR> et al. , Cell 22,817-23, 1980) genes that can be employed in tk-or aprt-cells,

respectively. Also, antimetabolite, antibiotic, or herbicide resistance can be used as the basis for selection. For example, dhfr confers resistance to methotrexate (Wigler <BR> <BR> et al. , Proc. Natl. Acad. Sci. 77,3567-70, 1980), npt confers resistance to the<BR> aminoglycosides, neomycin and G-418 (Colbere-Garapin et al. , J. Mol. Biol. 150, 1-14, 1981), and als and pat confer resistance to chlorsulfuron and phosphinotricin acetyltransferase, respectively (Murray, 1992, supra). Additional selectable genes have been described. For example, trpB allows cells to utilize indole in place of tryptophan, or hisD, which allows cells to utilize histinol in place of histidine (Hartman & Mulligan, Proc. Natl. Acad. Sci. 85,8047-51, 1988). Visible markers such as anthocyanins, p-glucuronidase and its substrate GUS, and luciferase and its substrate luciferin, can be used to identify transformants and to quantify the amount of transient or stable protein expression attributable to a specific vector system (Rhodes et al., Methods Mol. Biol. 55, 121-131,1995).

Detecting expression Although the presence of marker gene expression suggests that the cation transporting ATPase polynucleotide is also present, its presence and expression may need to be confirmed. For example, if a sequence encoding a human cation transporting ATPase polypeptide is inserted within a marker gene sequence, transformed cells containing sequences which encode an cation transporting ATPase polypeptide can be identified by the absence of marker gene function. Alternatively, a marker gene can be placed in tandem with a sequence encoding an cation transporting ATPase polypeptide under the control of a single promoter. Expression of the marker gene in response to induction or selection usually indicates expression of the cation transporting ATPase polynucleotide.

Alternatively, host cells which contain a human cation transporting ATPase polynucleotide and which express a human cation transporting ATPase polypeptide can be identified by a variety of procedures known to those of skill in the art. These procedures include, but are not limited to, DNA-DNA or DNA-RNA hybridizations and protein bioassay or immunoassay techniques that include membrane, solution, or

chip-based technologies for the detection and/or quantification of nucleic acid or protein. For example, the presence of a polynucleotide sequence encoding an cation transporting ATPase polypeptide can be detected by DNA-DNA or DNA-RNA hybridization or amplification using probes or fragments or fragments of polynucleotides encoding a human cation transporting ATPase polypeptide. Nucleic acid amplification-based assays involve the use of oligonucleotides selected from sequences encoding an cation transporting ATPase polypeptide to detect transformants which contain an cation transporting ATPase polynucleotide.

A variety of protocols for detecting and measuring the expression of a human cation transporting ATPase polypeptide, using either polyclonal or monoclonal antibodies specific for the polypeptide, are known in the art. Examples include enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA), and fluorescence activated cell sorting (FACS). A two-site, monoclonal-based immunoassay using monoclonal antibodies reactive to two non-interfering epitopes on a human cation transporting ATPase polypeptide can be used, or a competitive binding assay can be employed.

These and other assays are described in Hampton et al., SEROLOGICAL METHODS : A LABORATORY MANUAL, APS Press, St. Paul, Minn., 1990) and Maddox et al., J Exp.

Med. 158, 1211-1216, 1983).

A wide variety of labels and conjugation techniques are known by those skilled in the art and can be used in various nucleic acid and amino acid assays. Means for producing labeled hybridization or PCR probes for detecting sequences related to polynucleotides encoding cation transporting ATPase polypeptides include oligolabeling, nick translation, end-labeling, or PCR amplification using a labeled nucleotide. Alternatively, sequences encoding a human cation transporting ATPase polypeptide can be cloned into a vector for the production of an mRNA probe. Such vectors are known in the art, are commercially available, and can be used to synthesize RNA probes in vitro by addition of labeled nucleotides and an appropriate RNA polymerase such as T7, T3, or SP6. These procedures can be conducted using a variety of commercially available kits (Amersham Pharmacia Biotech, Promega,

and US Biochemical). Suitable reporter molecules or labels which can be used for ease of detection include radionuclides, enzymes, and fluorescent, chemiluminescent, or chromogenic agents, as well as substrates, cofactors, inhibitors, magnetic particles, and the like.

Expression andpurification of polypeptides Host cells transformed with nucleotide sequences encoding a human cation transporting ATPase polypeptide can be cultured under conditions suitable for the expression and recovery of the protein from cell culture. The polypeptide produced by a transformed cell can be secreted or contained intracellularly depending on the sequence and/or the vector used. As will be understood by those of skill in the art, expression vectors containing polynucleotides which encode cation transporting ATPase polypeptides can be designed to contain signal sequences which direct secretion of soluble cation transporting ATPase polypeptides through a prokaryotic or eukaryotic cell membrane or which direct the membrane insertion of membrane- bound cation transporting ATPase polypeptide.

As discussed above, other constructions can be used to join a sequence encoding a human cation transporting ATPase polypeptide to a nucleotide sequence encoding a polypeptide domain which will facilitate purification of soluble proteins. Such purification facilitating domains include, but are not limited to, metal chelating peptides such as histidine-tryptophan modules that allow purification on immobilized metals, protein A domains that allow purification on immobilized immunoglobulin, and the domain utilized in the FLAGS extension/affinity purification system <BR> <BR> (Immunex Corp. , Seattle, Wash. ). Inclusion of cleavable linker sequences such as those specific for Factor Xa or enterokinase (Invitrogen, San Diego, CA) between the purification domain and the cation transporting ATPase polypeptide also can be used to facilitate purification. One such expression vector provides for expression of a fusion protein containing a human cation transporting ATPase polypeptide and 6 histidine residues preceding a thioredoxin or an enterokinase cleavage site. The histidine residues facilitate purification by IMAC (immobilized metal ion affinity

chromatography, as described in Porath et al. , Prot. Exp. Purif. 3, 263-281, 1992), while the enterokinase cleavage site provides a means for purifying the cation transporting ATPase polypeptide from the fusion protein. Vectors that contain fusion proteins are disclosed in Kroll et al. , DNA Cell Biol. 12,441-453, 1993.

Chemical synthesis Sequences encoding a human cation transporting ATPase polypeptide can be synthesized, in whole or in part, using chemical methods well known in the art (see <BR> <BR> Caruthers et al. , Nucl. Acids Res. Symp. Ser. 215-223, 1980 ; Horn et al. Nucl. Acids Res. Symp. Ser. 225-232,1980). Alternatively, a human cation transporting ATPase polypeptide itself can be produced using chemical methods to synthesize its amino acid sequence, such as by direct peptide synthesis using solid-phase techniques (Merrifield, J. Am. Chem. Soc. 85,2149-2154, 1963; Roberge et al., Science 269, 202-204,1995). Protein synthesis can be performed using manual techniques or by automation. Automated synthesis can be achieved, for example, using Applied.

Biosystems 431A Peptide Synthesizer (Perkin Elmer). Optionally, fragments of cation transporting ATPase polypeptides can be separately synthesized and combined using chemical methods to produce a full-length molecule.

The newly synthesized peptide can be substantially purified by preparative high <BR> <BR> performance liquid chromatography (e. g. , Creighton, Proteins: Structures and<BR> Molecular Principles, WH Freeman and Co. , New York, N. Y. , 1983). The composition of a synthetic cation transporting ATPase polypeptide can be confirmed <BR> <BR> by amino acid analysis or sequencing (e. g. , the Edman degradation procedure ; see Creighton, supra). Additionally, any portion of the amino acid sequence of the cation transporting ATPase polypeptide can be altered during direct synthesis and/or combined using chemical methods with sequences from other proteins to produce a variant polypeptide or a fusion protein.

As will be understood by those of skill in the art, it may be advantageous to produce cation transporting ATPase polypeptide-encoding nucleotide sequences possessing

non-naturally occurring codons. For example, codons preferred by a particular prokaryotic or eukaryotic host can be selected to increase the rate of protein expression or to produce an RNA transcript having desirable properties, such as a half-life which is longer than that of a transcript generated from the naturally occurring sequence.

The nucleotide sequences disclosed herein can be engineered using methods generally known in the art to alter cation transporting ATPase polypeptide-encoding sequences for a variety of reasons, including but not limited to, alterations which modify the cloning, processing, and/or expression of the polypeptide or mRNA product. DNA shuffling by random fragmentation and PCR reassembly of gene fragments and synthetic oligonucleotides can be used to engineer the nucleotide sequences. For example, site-directed mutagenesis can be used to insert new restriction sites, alter glycosylation patterns, change codon preference, produce splice variants, introduce mutations, and so forth.

Antibodies Any type of antibody known in the art can be generated to bind specifically to an epitope of a human cation transporting ATPase polypeptide. "Antibody"as used herein includes intact immunoglobulin molecules, as well as fragments thereof, such as Fab, F (ab') 2, and Fv, which are capable of binding an epitope of a human cation transporting ATPase polypeptide. Typically, at least 6,8, 10, or 12 contiguous amino acids are required to form an epitope. However, epitopes which involve non- contiguous amino acids may require more, e. g. , at least 15,25, or 50 amino acids.

An antibody which specifically binds to an epitope of a human cation transporting ATPase polypeptide can be used therapeutically, as well as in immunochemical assays, such as Western blots, ELISAs, radioimmunoassays, immunohistochemical assays, immunoprecipitations, or other immunochemical assays known in the art.

Various immunoassays can be used to identify antibodies having the desired specificity. Numerous protocols for competitive binding or immunoradiometric

assays are well known in the art. Such immunoassays typically involve the measurement of complex formation between an immunogen and an antibody that specifically binds to the immunogen.

Typically, an antibody which specifically binds to a human cation transporting ATPase polypeptide provides a detection signal at least 5-, 10-, or 20-fold higher than a detection signal provided with other proteins when used in an immunochemical assay. Preferably, antibodies which specifically bind to cation transporting ATPase polypeptides do not detect other proteins in immunochemical assays and can immunoprecipitate a human cation transporting ATPase polypeptide from solution.

Human cation transporting ATPase polypeptides can be used to immunize a mammal, such as a mouse, rat, rabbit, guinea pig, monkey, or human, to produce polyclonal antibodies. If desired, a human cation transporting ATPase polypeptide can be conjugated to a carrier protein, such as bovine serum albumin, thyroglobulin, and keyhole limpet hemocyanin. Depending on the host species, various adjuvants can be used to increase the immunological response. Such adjuvants include, but are <BR> <BR> not limited to, Freund's adjuvant, mineral gels (e. g. , aluminum hydroxide), and surface active substances (e. g. lysolecithin, pluronic polyols, polyanions, peptides, oil emulsions, keyhole limpet hemocyanin, and dinitrophenol). Among adjuvants used in humans, BCG (bacilli Calmette-Guerin) and Corynebacterium parvum are especially useful.

Monoclonal antibodies which specifically bind to a human cation transporting ATPase polypeptide can be prepared using any technique which provides for the production of antibody molecules by continuous cell lines in culture. These techniques include, but are not limited to, the hybridoma technique, the human B-cell hybridoma technique, and the EBV-hybridoma technique (Kohler et al., Nature 256, <BR> <BR> 495-497,1985 ; Kozbor et al. , J. Immunol. Methods 81,31-42, 1985 ; Cote et al.,

Proc. Natl. Acad. Sci. 80,2026-2030, 1983; Cole et al. , Mol. Cell Biol. 62,109-120, 1984).

In addition, techniques developed for the production of"chimeric antibodies,"the splicing of mouse antibody genes to human antibody genes to obtain a molecule with appropriate antigen specificity and biological activity, can be used (Morrison et al., Proc. Natl. Acad. Sci. 81,6851-6855, 1984; Neuberger et al., Nature 312, 604-608, 1984 ; Takeda et al., Nature 314,452-454, 1985). Monoclonal and other antibodies also can be"humanized"to prevent a patient from mounting an immune response against the antibody when it is used therapeutically. Such antibodies may be sufficiently similar in sequence to human antibodies to be used directly in therapy or may require alteration of a few key residues. Sequence differences between rodent antibodies and human sequences can be minimized by replacing residues which differ from those in the human sequences by site directed mutagenesis of individual residues or by grating of entire complementarity determining regions. Alternatively, humanized antibodies can be produced using recombinant methods, as described in GB2188638B. Antibodies that specifically bind to a human cation transporting ATPase polypeptide can contain antigen binding sites which are either partially or fully humanized, as disclosed in U. S. 5,565, 332.

Alternatively, techniques described for the production of single chain antibodies can be adapted using methods known in the art to produce single chain antibodies that specifically bind to cation transporting ATPase polypeptides. Antibodies with related specificity, but of distinct idiotypic composition, can be generated by chain shuffling from random combinatorial immunoglobin libraries (Burton, Proc. Natl.

Acad. Sci. 88, 11120-23,1991).

Single-chain antibodies also can be constructed using a DNA amplification method, <BR> <BR> such as PCR, using hybridoma cDNA as a template (Thirion et al. , 1996, Eur. J.

Cancer Prev. 5,507-11). Single-chain antibodies can be mono-or bispecific, and can be bivalent or tetravalent. Construction of tetravalent, bispecific single-chain

antibodies is taught, for example, in Coloma & Morrison, 1997, Nat. Biotechnol. 15, 159-63. Construction of bivalent, bispecific single-chain antibodies is taught in Mallender & Voss, 1994, J. Biol. Chem. 269,199-206.

A nucleotide sequence encoding a single-chain antibody can be constructed using manual or automated nucleotide synthesis, cloned into an expression construct using standard recombinant DNA methods, and introduced into a cell to express the coding sequence, as described below. Alternatively, single-chain antibodies can be produced directly using, for example, filamentous phage technology (Verhaar et al. , 1995, Int.<BR> <P>J. Cancer 61,497-501 ; Nicholls et al. , 1993, J. Immunol. Meth. 165,81-91).

Antibodies which specifically bind to cation transporting ATPase polypeptides also can be produced by inducing in vivo production in the lymphocyte population or by screening immunoglobulin libraries or panels of highly specific binding reagents as disclosed in the literature (Orlandi et al. , Proc. Natl. Acad. Sci. 86, 3833-3837, 1989;<BR> Winter et al. , Nature 349,293-299, 1991).

Other types of antibodies can be constructed and used therapeutically in methods of the invention. For example, chimeric antibodies can be constructed as disclosed in WO 93/03151. Binding proteins which are derived from immunoglobulins and which are multivalent and multispecific, such as the"diabodies"described in WO 94/13804, also can be prepared.

Antibodies according to the invention can be purified by methods well known in the art. For example, antibodies can be affinity purified by passage over a column to which a human cation transporting ATPase polypeptide is bound. The bound antibodies can then be eluted from the column using a buffer with a high salt concentration.

Antisense oligonucleotides

Antisense oligonucleotides are nucleotide sequences which are complementary to a specific DNA or RNA sequence. Once introduced into a cell, the complementary nucleotides combine with natural sequences produced by the cell to form complexes and block either transcription or translation. Preferably, an antisense oligonucleotide is at least 11 nucleotides in length, but can be at least 12,15, 20,25, 30, 35, 40,45, or 50 or more nucleotides long. Longer sequences also can be used. Antisense oligonucleotide molecules can be provided in a DNA construct and introduced into a cell as described above to decrease the level of cation transporting ATPase gene products in the cell.

Antisense oligonucleotides can be deoxyribonucleotides, ribonucleotides, or a combination of both. Oligonucleotides can be synthesized manually or by an automated synthesizer, by covalently linking the 5'end of one nucleotide with the 3' end of another nucleotide with non-phosphodiester internucleotide linkages such alkylphosphonates, phosphorothioates, phosphorodithioates, alkylphosphonothioates, alkylphosphonates, phosphoramidates, phosphate esters, carbamates, acetamidate, carboxymethyl esters, carbonates, and phosphate triesters. See Brown, Meth. Mol.

Biol. 20, 1-8, 1994; Sonveaux, Meth. Mol. Biol. 26,1-72, 1994; Uhlmann et al., Chem. Rev. 90,543-583, 1990.

Modifications of cation transporting ATPase gene expression can be obtained by designing antisense oligonucleotides that will form duplexes to the control, 5', or regulatory regions of the cation transporting ATPase gene. Oligonucleotides derived from the transcription initiation site, e. g., between positions-10 and +10 from the start site, are preferred. Similarly, inhibition can be achieved using"triple helix" base-pairing methodology. Triple helix pairing is useful because it causes inhibition of the ability of the double helix to open sufficiently for the binding of polymerases, transcription factors, or chaperons. Therapeutic advances using triplex DNA have been described in the literature (e. g., Gee et al., in Huber & Carr, MOLECULAR AND <BR> <BR> IMMUNOLOGIC APPROACHES, Futura Publishing Co. , Mt. Kisco, N. Y., 1994). An

antisense oligonucleotide also can be designed to block translation of mRNA by preventing the transcript from binding to ribosomes.

Precise complementarity is not required for successful complex formation between an antisense oligonucleotide and the complementary sequence of a human cation transporting ATPase polynucleotide. Antisense oligonucleotides which comprise, for example, 2,3, 4, or 5 or more stretches of contiguous nucleotides which are precisely complementary to an cation transporting ATPase polynucleotide, each separated by a stretch of contiguous nucleotides which are not complementary to adjacent cation transporting ATPase nucleotides, can provide sufficient targeting specificity for cation transporting ATPase mRNA. Preferably, each stretch of complementary contiguous nucleotides is at least 4,5, 6,7, or 8 or more nucleotides in length. Non- complementary intervening sequences are preferably 1, 2,3, or 4 nucleotides in length. One skilled in the art can easily use the calculated melting point of an antisense-sense pair to determine the degree of mismatching which will be tolerated between a particular antisense oligonucleotide and a particular cation transporting ATPase polynucleotide sequence.

Antisense oligonucleotides can be modified without affecting their ability to hybridize to a human cation transporting ATPase polynucleotide. These modifi- cations can be internal or at one or both ends of the antisense molecule. For example, internucleoside phosphate linkages can be modified by adding cholesteryl or diamine moieties with varying numbers of carbon residues between the amino groups and terminal ribose. Modified bases and/or sugars, such as arabinose instead of ribose, or a 3', 5'-substituted oligonucleotide in which the 3'hydroxyl group or the 5' phosphate group are substituted, also can be employed in a modified antisense oligonucleotide. These modified oligonucleotides can be prepared by methods well <BR> <BR> known in the art. See, e. g. , Agrawal et al., Trends Biotechnol. 10, 152-158, 1992; Uhlmann et al., Chem. Rev. 90, 543-584,1990 ; Uhlmann et al., Tetrahedron. Lett.

215, 3539-3542,1987.

Ribozymes Ribozymes are RNA molecules with catalytic activity. See, e. g., Cech, Science 236, 1532-1539; 1987; Cech, Ann. Rev. Biochem. 59,543-568 ; 1990, Cech, Curr. Opin.

Struct. Biol. 2,605-609 ; 1992, Couture & Stinchcomb, Trends Genet. 12,510-515, 1996. Ribozymes can be used to inhibit gene function by cleaving an RNA sequence, as is known in the art (e. g., Haseloff et al. , U. S. Patent 5,641, 673). The mechanism of ribozyme action involves sequence-specific hybridization of the ribozyme molecule to complementary target RNA, followed by endonucleolytic cleavage.

Examples include engineered hammerhead motif ribozyme molecules that can specifically and efficiently catalyze endonucleolytic cleavage of specific nucleotide sequences.

The coding sequence of a human cation transporting ATPase polynucleotide can be used to generate ribozymes that will specifically bind to mRNA transcribed from the cation transporting ATPase polynucleotide. Methods of designing and constructing ribozymes which can cleave other RNA molecules in trans in a highly sequence specific manner have been developed and described in the art (see Haseloff et al.

Nature 334,585-591, 1988). For example, the cleavage activity of ribozymes can be targeted to specific RNAs by engineering a discrete"hybridization"region into the ribozyme. The hybridization region contains a sequence complementary to the target RNA and thus specifically hybridizes with the target (see, for example, Gerlach et al., EP 321,201).

Specific ribozyme cleavage sites within a human cation transporting ATPase RNA target can be identified by scanning the target molecule for ribozyme cleavage sites which include the following sequences: GUA, GUU, and GUC. Once identified, short RNA sequences of between 15 and 20 ribonucleotides corresponding to the region of the target RNA containing the cleavage site can be evaluated for secondary structural features which may render the target inoperable. Suitability of candidate cation transporting ATPase RNA targets also can be evaluated by testing accessibility to hybridization with complementary oligonucleotides using ribonuclease protection

assays. Longer complementary sequences can be used to increase the affinity of the hybridization sequence for the target. The hybridizing and cleavage regions of the ribozyme can be integrally related such that upon hybridizing to the target RNA through the complementary regions, the catalytic region of the ribozyme can cleave the target.

Ribozymes can be introduced into cells as part of a DNA construct. Mechanical methods, such as microinjection, liposome-mediated transfection, electroporation, or calcium phosphate precipitation, can be used to introduce a ribozyme-containing DNA construct into cells in which it is desired to decrease cation transporting ATPase expression. Alternatively, if it is desired that the cells stably retain the DNA construct, the construct can be supplied on a plasmid and maintained as a separate element or integrated into the genome of the cells, as is known in the art. A ribozyme-encoding DNA construct can include transcriptional regulatory elements, such as a promoter element, an enhancer or UAS element, and a transcriptional terminator signal, for controlling transcription of ribozymes in the cells. <BR> <BR> <P>As taught in Haseloff et al. , U. S. Patent 5,641, 673, ribozymes can be engineered so that ribozyme expression will occur in response to factors that induce expression of a target gene. Ribozymes also can be engineered to provide an additional level of regulation, so that destruction of mRNA occurs only when both a ribozyme and a target gene are induced in the cells.

Differentially expressed genes Described herein are methods for the identification of genes whose products interact with human cation transporting ATPase. Such genes may represent genes that are differentially expressed in respiratory disorders including but not limited to asthma and urological disorders. Further, such genes may represent genes that are differentially regulated in response to manipulations relevant to the progression or treatment of such diseases. Additionally, such genes may have a temporally modulated expression, increased or decreased at different stages of tissue or organism

development. A differentially expressed gene may also have its expression modulated under control versus experimental conditions. In addition, the human cation transporting ATPase gene or gene product may itself be tested for differential expression.

The degree to which expression differs in a normal versus a diseased state need only be large enough to be visualized via standard characterization techniques such as differential display techniques. Other such standard characterization techniques by which expression differences may be visualized include but are not limited to, quantitative RT (reverse transcriptase), PCR, and Northern analysis.

To identify differentially expressed genes total RNA or, preferably, mRNA is isolated from tissues of interest. For example, RNA samples are obtained from tissues of experimental subjects and from corresponding tissues of control subjects.

Any RNA isolation technique that does not select against the isolation of mRNA may be utilized for the purification of such RNA samples. See, for example, Ausubel et <BR> <BR> al. , ed., Current Protocols in Molecular Biology, John Wiley & Sons, Inc. New York, 1987-1993. Large numbers of tissue samples may readily be processed using techniques well known to those of skill in the art, such as, for example, the single- step RNA isolation process of Chomczynski, U. S. Patent 4, 843, 155.

Transcripts within the collected RNA samples that represent RNA produced by differentially expressed genes are identified by methods well known to those of skill <BR> <BR> in the art. They include, for example, differential screening (Tedder et al. , Proc. Natl.

Acad. Sci. U. S. A. 85,208-12, 1988), subtractive hybridization (Hedrick et al., Nature <BR> <BR> 308,149-53 ; Lee et al. , Proc. Natl. Acad. Sci. U. S. A. 88,2825, 1984), and, preferably, differential display (Liang & Pardee, Science 257,967-71, 1992; U. S.

Patent 5,262, 311).

The differential expression information may itself suggest relevant methods for the treatment of disorders involving the human cation transporting ATPase. For

example, treatment may include a modulation of expression of the differentially expressed genes and/or the gene encoding the human cation transporting ATPase.

The differential expression information may indicate whether the expression or activity of the differentially expressed gene or gene product or the human cation transporting ATPase gene or gene product are up-regulated or down-regulated.

Screening methods The invention provides assays for screening test compounds that bind to or modulate the activity of a human cation transporting ATPase polypeptide or a human cation transporting ATPase polynucleotide. A test compound preferably binds to a human cation transporting ATPase polypeptide or polynucleotide. More preferably, a test compound decreases or increases enzymatic activity by at least about 10, preferably about 50, more preferably about 75,90, or 100% relative to the absence of the test compound.

Test compounds Test compounds can be pharmacologic agents already known in the art or can be compounds previously unknown to have any pharmacological activity. The compounds can be naturally occurring or designed in the laboratory. They can be isolated from microorganisms, animals, or plants, and can be produced recombinantly, or synthesized by chemical methods known in the art. If desired, test compounds can be obtained using any of the numerous combinatorial library methods known in the art, including but not limited to, biological libraries, spatially addressable parallel solid phase or solution phase libraries, synthetic library methods requiring deconvolution, the"one-bead one-compound"library method, and synthetic library methods using affinity chromatography selection. The biological library approach is limited to polypeptide libraries, while the other four approaches are applicable to polypeptide, non-peptide oligomer, or small molecule libraries of compounds. See Lam, Anticancer Drug Des. 12,145, 1997.

Methods for the synthesis of molecular libraries are well known in the art (see, for example, DeWitt et al. , Proc. Natl. Acad. Sci. U. S. A. 90,6909, 1993; Erb et al. Proc.<BR> <P>Natl. Acad. Sci. U. S. A. 91,11422, 1994; Zuckermann et al. , J. Med. Chem. 37,<BR> 2678,1994 ; Cho et al., Science 261,1303, 1993; Carell et al. , Angew. Chem. Int. Ed.<BR> <P>Engl. 33,2059, 1994; Carell et al. , Angew. Chem. Int. Ed. Engl. 33,2061 ; Gallop et<BR> al. , J. Med. Chem. 37,1233, 1994). Libraries of compounds can be presented in<BR> solution (see, e. g. , Houghten, BioTechniques 13,412-421, 1992), or on beads (Lam, Nature 354, 82-84, 1991), chips (Fodor, Nature 364,555-556, 1993), bacteria or spores (Ladner, U. S. Patent 5,223, 409), plasmids (Cull et al. , Proc. Natl. Acad. Sci.

U. S. A. 89,1865-1869, 1992), or phage (Scott & Smith, Science 249,386-390, 1990; Devlin, Science 249, 404-406,1990) ; Cwirla et al., Proc. Natl. Acad. Sci. 97, 6378-6382,1990 ; Felici, J. Mol. Biol. 222,301-310, 1991; and Ladner, U. S. Patent 5,223, 409).

High through-put screening Test compounds can be screened for the ability to bind to cation transporting ATPase polypeptides or polynucleotides or to affect cation transporting ATPase activity or cation transporting ATPase gene expression using high throughput screening. Using high throughput screening, many discrete compounds can be tested in parallel so that large numbers of test compounds can be quickly screened. The most widely established techniques utilize 96-well microtiter plates. The wells of the microtiter plates typically require assay volumes that range from 50 to 500 J. l. In addition to the plates, many instruments, materials, pipettors, robotics, plate washers, and plate readers are commercially available to fit the 96-well format.

Alternatively, "free format assays, "or assays that have no physical barrier between samples, can be used. For example, an assay using pigment cells (melanocytes) in a simple homogeneous assay for combinatorial peptide libraries is described by Jayawickreme et al. , Proc. Natl. Acad. Sci. U. S. A. 19, 1614-18 (1994). The cells are placed under agarose in petri dishes, then beads that carry combinatorial compounds are placed on the surface of the agarose. The combinatorial compounds are partially

released the compounds from the beads. Active compounds can be visualized as dark pigment areas because, as the compounds diffuse locally into the gel matrix, the active compounds cause the cells to change colors.

Another example of a free format assay is described by Chelsky,"Strategies for Screening Combinatorial Libraries: Novel and Traditional Approaches, "reported at the First Annual Conference of The Society for Biomolecular Screening in Philadelphia, Pa. (Nov. 7-10, 1995). Chelsky placed a simple homogenous enzyme assay for carbonic anhydrase inside an agarose gel such that the enzyme in the gel would cause a color change throughout the gel. Thereafter, beads carrying combinatorial compounds via a photolinker were placed inside the gel and the compounds were partially released by UV-light. Compounds that inhibited the enzyme were observed as local zones of inhibition having less color change.

Yet another example is described by Salmon et al., Molecular Diversity 2,57-63 (1996). In this example, combinatorial libraries were screened for compounds that had cytotoxic effects on cancer cells growing in agar.

Another high throughput screening method is described in Beutel et al., U. S. Patent 5,976, 813. In this method, test samples are placed in a porous matrix. One or more assay components are then placed within, on top of, or at the bottom of a matrix such as a gel, a plastic sheet, a filter, or other form of easily manipulated solid support.

When samples are introduced to the porous matrix they diffuse sufficiently slowly, such that the assays can be performed without the test samples running together.

Binding assays For binding assays, the test compound is preferably a small molecule that binds to and occupies, for example, the active site of the cation transporting ATPase polypeptide, such that normal biological activity is prevented. Examples of such small molecules include, but are not limited to, small peptides or peptide-like molecules.

In binding assays, either the test compound or the cation transporting ATPase polypeptide can comprise a detectable label, such as a fluorescent, radioisotopic, chemiluminescent, or enzymatic label, such as horseradish peroxidase, alkaline phosphatase, or luciferase. Detection of a test compound that is bound to the cation transporting ATPase polypeptide can then be accomplished, for example, by direct counting of radioemmission, by scintillation counting, or by determining conversion of an appropriate substrate to a detectable product.

Alternatively, binding of a test compound to a human cation transporting ATPase polypeptide can be determined without labeling either of the interactants. For example, a microphysiometer can be used to detect binding of a test compound with a human cation transporting ATPase polypeptide. A microphysiometer (e. g., Cytosensor) is an analytical instrument that measures the rate at which a cell acidifies its environment using a light-addressable potentiometric sensor (LAPS).

Changes in this acidification rate can be used as an indicator of the interaction between a test compound and a human cation transporting ATPase polypeptide (McConnell et al., Science 257,1906-1912, 1992).

Determining the ability of a test compound to bind to a human cation transporting ATPase polypeptide also can be accomplished using a technology such as real-time Bimolecular Interaction Analysis (BIA) (Sjolander & Urbaniczky, Anal. Chem. 63, 2338-2345,1991, and Szabo et al., Curr. Opin. Struct. Biol. 5, 699-705,1995). BIA is a technology for studying biospecific interactions in real time, without labeling any of the interactants (e. g., BIAcoreTM). Changes in the optical phenomenon surface plasmon resonance (SPR) can be used as an indication of real-time reactions between biological molecules.

In yet another aspect of the invention, a human cation transporting ATPase polypeptide can be used as a"bait protein"in a two-hybrid assay or three-hybrid assay (see, e. g., U. S. Patent 5,283, 317; Zervos et al., Cell 72, 223-232,1993 ; Madura

et al., J : Biol. Chem. 26S, 12046-12054,1993 ; Bartel et al., BioTechniques 14, 920-924,1993 ; Iwabuchi et al., Oncogene 8,1693-1696, 1993; and Brent W094/10300), to identify other proteins which bind to or interact with the cation transporting ATPase polypeptide and modulate its activity.

The two-hybrid system is based on the modular nature of most transcription factors, which consist of separable DNA-binding and activation domains. Briefly, the assay utilizes two different DNA constructs. For example, in one construct, polynucleotide. encoding a human cation transporting ATPase polypeptide can be fused to a polynucleotide encoding the DNA binding domain of a known transcription factor (e. g. , GAL-4). In the other construct a DNA sequence that encodes an unidentified protein ("prey"or"sample") can be fused to a polynucleotide that codes for the activation domain of the known transcription factor. If the"bait"and the"prey" proteins are able to interact in vivo to form an protein-dependent complex, the DNA-binding and activation domains of the transcription factor are brought into close proximity. This proximity allows transcription of a reporter gene (e. g., LacZ), which is operably linked to a transcriptional regulatory site responsive to the transcription factor. Expression of the reporter gene can be detected, and cell colonies containing the functional transcription factor can be isolated and used to obtain the DNA sequence encoding the protein that interacts with the cation transporting ATPase polypeptide.

It may be desirable to immobilize either the cation transporting ATPase polypeptide (or polynucleotide) or the test compound to facilitate separation of bound from unbound forms of one or both of the interactants, as well as to accommodate automation of the assay. Thus, either the cation transporting ATPase polypeptide (or polynucleotide) or the test compound can be bound to a solid support. Suitable solid supports include, but are not limited to, glass or plastic slides, tissue culture plates, microtiter wells, tubes, silicon chips, or particles such as beads (including, but not limited to, latex, polystyrene, or glass beads). Any method known in the art can be used to attach the enzyme polypeptide (or polynucleotide) or test compound to a

solid support, including use of covalent and non-covalent linkages, passive absorption, or pairs of binding moieties attached respectively to the polypeptide (or polynucleotide) or test compound and the solid support. Test compounds are preferably bound to the solid support in an array, so that the location of individual test compounds can be tracked. Binding of a test compound to a human cation transporting ATPase polypeptide (or polynucleotide) can be accomplished in any vessel suitable for containing the reactants. Examples of such vessels include microtiter plates, test tubes, and microcentrifuge tubes.

In one embodiment, the cation transporting ATPase polypeptide is a fusion protein comprising a domain that allows the cation transporting ATPase polypeptide to be bound to a solid support. For example, glutathione-S-transferase fusion proteins can <BR> <BR> be adsorbed onto glutathione sepharose beads (Sigma Chemical, St. Louis, Mo. ) or glutathione derivatized microtiter plates, which are then combined with the test compound or the test compound and the non-adsorbed cation transporting ATPase polypeptide ; the mixture is then incubated under conditions conducive to complex <BR> <BR> formation (e. g. , at physiological conditions for salt and pH). Following incubation, the beads or microtiter plate wells are washed to remove any unbound components.

Binding of the interactants can be determined either directly or indirectly, as described above. Alternatively, the complexes can be dissociated from the solid support before binding is determined.

Other techniques for immobilizing proteins or polynucleotides on a solid support also can be used in the screening assays of the invention. For example, either a human cation transporting ATPase polypeptide (or polynucleotide) or a test compound can be immobilized utilizing conjugation of biotin and streptavidin. Biotinylated cation transporting ATPase polypeptides (or polynucleotides) or test compounds can be prepared from biotin-NHS (N- hydroxysuccinimide) using techniques well known in <BR> <BR> the art (e. g. , biotinylation kit, Pierce Chemicals, Rockford, Ill.) and immobilized in the wells of streptavidin-coated 96 well plates (Pierce Chemical). Alternatively, antibodies which specifically bind to a cation transporting ATPase polypeptide,

polynucleotide, or a test compound, but which do not interfere with a desired binding site, such as the active site of the cation transporting ATPase polypeptide, can be derivatized to the wells of the plate. Unbound target or protein can be trapped in the wells by antibody conjugation.

Methods for detecting such complexes, in addition to those described above for the GST-immobilized complexes, include immunodetection of complexes using antibodies which specifically bind to the cation transporting ATPase polypeptide or test compound, enzyme-linked assays which rely on detecting an activity of the cation transporting ATPase polypeptide, and SDS gel electrophoresis under non- reducing conditions.

Screening for test compounds which bind to a human cation transporting ATPase polypeptide or polynucleotide also can be carried out in an intact cell. Any cell which comprises a cation transporting ATPase polypeptide or polynucleotide can be used in a cell-based assay system. A cation transporting ATPase polynucleotide can be naturally occurring in the cell or can be introduced using techniques such as those described above. Binding of the test compound to a cation transporting ATPase polypeptide or polynucleotide is determined as described above.

Enzymatic activity Test compounds can be tested for the ability to increase or decrease the enzymatic activity of a human cation transporting ATPase polypeptide. Enzymatic activity can be measured, for example, as described in J Biochem Mol Toxicol 1999; 13 (2): 93- 106.

Enzyme assays can be carried out after contacting either a purified cation transporting ATPase polypeptide, a cell membrane preparation, or an intact cell with a test compound. A test compound that decreases enzymatic activity of a human cation transporting ATPase polypeptide by at least about 10, preferably about 50, more preferably about 75,90, or 100% is identified as a potential therapeutic agent for

decreasing cation transporting ATPase activity. A test compound which increases enzymatic activity of a human cation transporting ATPase polypeptide by at least about 10, preferably about 50, more preferably about 75,90, or 100% is identified as a potential therapeutic agent for increasing human cation transporting ATPase activity.

Gene expression In another embodiment, test compounds that increase or decrease cation transporting ATPase gene expression are identified. A cation transporting ATPase polynucleotide is contacted with a test compound, and the expression of an RNA or polypeptide product of the cation transporting ATPase polynucleotide is determined. The level of expression of appropriate mRNA or polypeptide in the presence of the test compound is compared to the level of expression of mRNA or polypeptide in the absence of the test compound. The test compound can then be identified as a modulator of expression based on this comparison. For example, when expression of mRNA or polypeptide is greater in the presence of the test compound than in its absence, the test compound is identified as a stimulator or enhancer of the mRNA or polypeptide expression. Alternatively, when expression of the mRNA or polypeptide is less in the presence of the test compound than in its absence, the test compound is identified as an inhibitor of the mRNA or polypeptide expression.

The level of cation transporting ATPase mRNA or polypeptide expression in the cells can be determined by methods well known in the art for detecting mRNA or polypeptide. Either qualitative or quantitative methods can be used. The presence of polypeptide products of a human cation transporting ATPase polynucleotide can be determined, for example, using a variety of techniques known in the art, including immunochemical methods such as radioimmunoassay, Western blotting, and immunohistochemistry. Alternatively, polypeptide synthesis can be determined in vivo, in a cell culture, or in an in vitro translation system by detecting incorporation of labeled amino acids into a human cation transporting ATPase polypeptide.

Such screening can be carried out either in a cell-free assay system or in an intact cell. Any cell that expresses a human cation transporting ATPase polynucleotide can be used in a cell-based assay system. The cation transporting ATPase polynucleotide can be naturally occurring in the cell or can be introduced using techniques such as those described above. Either a primary culture or an established cell line, such as CHO or human embryonic kidney 293 cells, can be used.

Pharmaceutical compositions The invention also provides pharmaceutical compositions that can be administered to a patient to achieve a therapeutic effect. Pharmaceutical compositions of the invention can comprise, for example, a human cation transporting ATPase polypeptide, cation transporting ATPase polynucleotide, ribozymes or antisense oligonucleotides, antibodies which specifically bind to a cation transporting ATPase polypeptide, or mimetics, activators, or inhibitors of a human cation transporting ATPase polypeptide activity. The compositions can be administered alone or in combination. with at least one other agent, such as stabilizing compound, which can be administered in any sterile, biocompatible pharmaceutical carrier, including, but not limited to, saline, buffered saline, dextrose, and water. The compositions can be administered to a patient alone, or in combination with other agents, drugs or hormones.

In addition to the active ingredients, these pharmaceutical compositions can contain suitable pharmaceutically-acceptable carriers comprising excipients and auxiliaries that facilitate processing of the active compounds into preparations which can be used pharmaceutically. Pharmaceutical compositions of the invention can be administered by any number of routes including, but not limited to, oral, intravenous, intramuscular, intra-arterial, intramedullary, intrathecal, intraventricular, transdermal, subcutaneous, intraperitoneal, intranasal, parenteral, topical, sublingual, or rectal means. Pharmaceutical compositions for oral administration can be formulated using pharmaceutically acceptable carriers well known in the art in dosages suitable for oral administration. Such carriers enable the pharmaceutical compositions to be

formulated as tablets, pills, dragees, capsules, liquids, gels, syrups, slurries, suspensions, and the like, for ingestion by the patient.

Pharmaceutical preparations for oral use can be obtained through combination of active compounds with solid excipient, optionally grinding a resulting mixture, and processing the mixture of granules, after adding suitable auxiliaries, if desired, to obtain tablets or dragee cores. Suitable excipients are carbohydrate or protein fillers, such as sugars, including lactose, sucrose, mannitol, or sorbitol; starch from corn, wheat, rice, potato, or other plants; cellulose, such as methyl cellulose, hydroxypropylmethyl-cellulose, or sodium carboxymethylcellulose ; gums including arabic and tragacanth; and proteins such as gelatin and collagen. If desired, disintegrating or solubilizing agents can be added, such as the cross-linked polyvinyl pyrrolidone, agar, alginic acid, or a salt thereof, such as sodium alginate.

Dragee cores can be used in conjunction with suitable coatings, such as concentrated sugar solutions, which also can contain gum arabic, talc, polyvinylpyrrolidone, carbopol gel, polyethylene glycol, and/or titanium dioxide, lacquer solutions, and suitable organic solvents or solvent mixtures. Dyestuffs or pigments can be added to the tablets or dragee coatings for product identification or to characterize the quantity of active compound, i. e. , dosage.

Pharmaceutical preparations that can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a coating, such. as glycerol or sorbitol. Push-fit capsules can contain active ingredients mixed with a filler or binders, such as lactose or starches, lubricants, such as talc or magnesium stearate, and, optionally, stabilizers. In soft capsules, the active compounds can be dissolved or suspended in suitable liquids, such as fatty oils, liquid, or liquid polyethylene glycol with or without stabilizers.

Pharmaceutical formulations suitable for parenteral administration can be formulated in aqueous solutions, preferably in physiologically compatible buffers such as Hanks'

solution, Ringer's solution, or physiologically buffered saline. Aqueous injection suspensions can contain substances that increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. Additionally, suspensions of the active compounds can be prepared as appropriate oily injection suspensions.

Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic'fatty acid esters, such as ethyl oleate or triglycerides, or liposomes.

Non-lipid polycationic amino polymers also can be used for delivery. Optionally, the suspension also can contain suitable stabilizers or agents that increase the solubility of the compounds to allow for the preparation of highly concentrated solutions. For topical or nasal administration, penetrants appropriate to the particular barrier to be permeated are used in the formulation. Such penetrants are generally known in the art.

The pharmaceutical compositions of the present invention can be manufactured in a <BR> <BR> manner that is known in the art, e. g. , by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping, or lyophilizing processes. The pharmaceutical composition can be provided as a salt and can be formed with many acids, including but not limited to, hydrochloric, sulfuric, acetic, lactic, tartaric, malic, succinic, etc. Salts tend to be more soluble in aqueous or other protonic solvents than are the corresponding free base forms. In other cases, the preferred preparation can be a lyophilized powder which can contain any or all of the following: 1-50 mM histidine, 0.1%-2% sucrose, and 2-7% mannitol, at a pH range of 4.5 to 5.5, that is combined with buffer prior to use.

Further details on techniques for formulation and administration can be found in the latest edition of Remington's Pharmaceutical Sciences (Maack Publishing Co., <BR> <BR> Easton, Pa. ). After pharmaceutical compositions have been prepared, they can be placed in an appropriate container and labeled for treatment of an indicated condition. Such labeling would include amount, frequency, and method of administration.

Therapeutic indications and methods Human cation transporting ATPase can be regulated to treat thyroid, urological and respiratory disorders including but not limited to asthma.

Urinary Incontinence Urinary incontinence (UI) is the involuntary loss of urine. Urge urinary incontinence (UUI) is one of the most common types of UI together with stress urinary incontinence (SUI), which is usually caused by a defect in the urethral closure mechanism. UUI is often associated with neurological disorders or diseases causing neuronal damage, such as dementia, Parkinson's disease, multiple sclerosis, stroke, and diabetes, although it also occurs in individuals with no such disorders. One of the usual causes of UUI is overactive bladder (OAB), which is a medical condition referring to the symptoms of frequency and urgency derived from abnormal contractions and instability of the detrusor muscle.

There are several medications for urinary incontinence on the market today, mainly to help treating WI. Therapy for OAB is focused on drugs that affect peripheral neural control mechanisms or those that act directly on bladder detrusor smooth muscle contraction, with a major emphasis on development of anticholinergic agents. These agents can inhibit the parasympathetic nerves, which control bladder voiding, or can exert a direct spasmolytic effect on the detrusor muscle of the bladder. This results in a decrease in intravesicular pressure, an increase in capacity, and a reduction in the frequency of bladder contraction. Orally active anticholinergic drugs, such as propantheline (ProBanthine), tolterodine tartrate (Detrol), and oxybutynin (Ditropan), are the most commonly prescribed drugs. However, their most serious drawbacks are unacceptable side effects, such as dry mouth, abnormal visions, constipation, and central nervous system disturbances. These side effects lead to poor compliance. Dry mouth symptoms alone are responsible for a 70% non-compliance rate with oxybutynin. The inadequacies of present therapies highlight the need for novel, efficacious, safe, orally available drugs that have fewer side effects.

Benign Prostatic Hyperplasia.

Benign prostatic hyperplasia (BPH) is the benign nodular hyperplasia of the periurethral prostate gland commonly seen in men over the age of 50. The overgrowth occurs in the central area of the prostate called the transition zone, which wraps around the urethra. BPH causes variable degrees of bladder outlet obstruction, resulting in progressive lower urinary tract syndromes (LUTS) characterized by urinary frequency, urgency, and nocturia due to incomplete emptying and rapid refilling of the bladder. The actual cause of BPH is unknown but may involve age- related alterations in balance of steroidal sex hormones.

Selective al-adrenoceptor antagonists, such as prazosin, indoramin, and tamsulosin, are used as an adjunct in the symptomatic treatment of urinary obstruction caused by BPH, although they do not affect on the underlying cause of BPH. In BPH, increased sympathetic tone exacerbates the degree of obstruction of the urethra through contraction of prostatic and urethral smooth muscle. These compounds inhibit sympathetic activity, thereby relaxing the smooth muscle of the urinary tract.

Uroselective al-antagonists and al-antagonists with high tissue selectivity for lower urinary tract smooth muscle that do not provoke hypotensive side-effects should be developed for the treatment.

Drugs blocking dihydrotestosterone have been used to reduce the size of the prostate.

5a-reductase inhibitors such as finasteride are prescribed for BPH. These agents selectively inhibit Sa-reductase which mediates conversion of testosterone to dihydrotestosterone, thereby reducing plasma dihydrotestosterone levels and, thus, prostate growth. The 5a-reductase inhibitors do not bind to androgen receptors and do not affect testosterone levels, nor do they possess feminizing side-effects.

Androgen receptor antagonists are used for the treatment of prostatic hyperplasia due to excessive action or production of testosterone. Various antiandrogens are under investigation for BPH including chlormadione derivatives with no estrogenic activity,

orally-active aromatase inhibitors, and luteinizing hormone-releasing hormone (LHRH) analogues.

Allergies and asthma Allergy is a complex process in which environmental antigens induce clinically adverse reactions. The inducing antigens, called allergens, typically elicit a specific IgE response and, although in most cases the allergens themselves have little or no intrinsic toxicity, they induce pathology when the IgE response in turn elicits an IgE- dependent or T cell-dependent hypersensitivity reaction. Hypersensitivity reactions can be local or systemic and typically occur within minutes of allergen exposure in individuals who have previously been sensitized to an allergen. The hypersensitivity reaction of allergy develops when the allergen is recognized by IgE antibodies bound to specific receptors on the surface of effector cells, such as mast cells, basophils, or eosinophils, which causes the activation of the effector cells and the release of mediators that produce the acute signs and symptoms of the reactions. Allergic diseases include asthma, allergic rhinitis (hay fever), atopic dermatitis, and anaphylaxis.

Asthma is though to arise as a result of interactions between multiple genetic and environmental factors and is characterized by three-major features: 1) intermittent and reversible airway obstruction caused by bronchoconstriction, increased mucus production, and thickening of the walls of the airways that leads to a narrowing of the airways, 2) airway hyperresponsiveness caused by a decreased control of airway caliber, and 3) airway inflammation. Certain cells are critical to the inflammatory reaction of asthma and they include T cells and antigen presenting cells, B cells that produce IgE, and mast cells, basophils, eosinophils, and other cells that bind IgE.

These effector cells accumulate at the site of allergic reaction in the airways and release toxic products that contribute to the acute pathology and eventually to the tissue destruction related to the disorder. Other resident cells, such as smooth muscle cells, lung epithelial cells, mucus-producing cells, and nerve cells may also be abnormal in individuals with asthma and may contribute to the pathology. While the

airway obstruction of asthma, presenting clinically as an intermittent wheeze and shortness of breath, is generally the most pressing symptom of the disease requiring immediate treatment, the inflammation and tissue destruction associated with the disease can lead to irreversible changes that eventually make asthma a chronic disabling disorder requiring long-term management.

Despite recent important advances in our understanding of the pathophysiology of asthma, the disease appears to be increasing in prevalence and severity (Gergen and Weiss, Am. Rev. Respir. Dis. 146, 823-24,1992). It is estimated that 30-40% of the population suffer with atopic allergy, and 15% of children and 5% of adults in the population suffer from asthma (Gergen and Weiss, 1992). Thus, an enormous burden is placed on our health care resources. However, both diagnosis and treatment of asthma are difficult. The severity of lung tissue inflammation is not easy to measure and the symptoms of the disease are often indistinguishable from those of respiratory infections, chronic respiratory inflammatory disorders, allergic rhinitis, or other respiratory disorders. Often, the inciting allergen cannot be determined, making removal of the causative environmental agent difficult.

Current pharmacological treatments suffer their own set of disadvantages. Commonly used therapeutic agents, such as beta agonists, can act as symptom relievers to transiently improve pulmonary function, but do not affect the underlying inflammation. Agents that can reduce the underlying inflammation, such as anti- inflammatory steroids, can have major drawbacks that range from immunosuppression to bone loss (Goodman and Gilman's THE PHARMACOLOGIC BASIS OF THERAPEUTICS, Seventh Edition, MacMillan Publishing Company, NY,- USA, 1985). In addition, many of the present therapies, such as inhaled corticosteroids, are short-lasting, inconvenient to use, and must be used often on a regular basis, in some cases for life, making failure of patients to comply with the treatment a major problem and thereby reducing their effectiveness as a treatment.

Because of the problems associated with conventional therapies, alternative treatment

strategies have been evaluated. Glycophorin A (Chu and Sharom, Cell. Immunol.

145, 223-39,1992), cyclosporin (Alexander et al., Lancet 339, 324-28,1992), and a nonapeptide fragment of IL-2 (Zav'yalov et al., Immunol. Lett. 31, 285-88, 1992) all inhibit interleukin-2 dependent T lymphocyte proliferation; however, they are known to have many other effects. For example, cyclosporin is used as a immuno- suppressant after organ transplantation. While these agents may represent alternatives to steroids in the treatment of asthmatics, they inhibit interleukin-2 dependent T lymphocyte proliferation and potentially critical immune functions associated with homeostasis.

Other treatments that block the release or activity of mediators of bronchochonstriction, such as cromones or anti-leukotrienes, have recently been introduced for the treatment of mild asthma, but they are expensive and not effective in all patients and it is unclear whether they have any effect on the chronic changes associated with asthmatic inflammation. What is needed in the art is the identification of a treatment that can act in pathways critical to the development of asthma that both blocks the episodic attacks of the disorder and preferentially dampens the hyperactive allergic immune response without immunocompromising the patient.

Two functions of cation transporting ATPases with relevance to asthma are the transport of calcium ions across membranes and the transport of cations into and out of the extracellular milieu. Calcium ion transport is a necessary component of most cell-surface receptor initiated signalling cascades. Many of the drugs currently used to treat asthma and related disorders act on receptors, for example beta adrenergic receptors or adenosine receptors, that upon binding a ligand induce the mobilization of calcium ions across the plasma membrane and the membranes of intracellular organelles in order to raise cytoplasmic calcium ion levels. The increased calcium ion levels in turn activate cytoplasmic proteins which father propagate the signal, finally resulting in cellular responses such as growth, shape changes, release of inflammatory mediators, or muscle contraction. Regulation of human cation

transporting ATPase can therefore be useful in blocking or enhancing receptor- mediated cellular responses.

Transport of cations into and out of cells in the lung is an important mechanism for regulating extracellular fluid levels in the lungs. During hypoxic states, for example, fluid resorption in the lungs is inhibited due to impaired cation transport, leading to pulmonary edema. In asthma and other inflammatory states in the respiratory tract, edema is an important cause of airway narrowing, resulting in decreased lung capacity, dereased airflow, wheezing, increased susceptibility to attacks of symptomatic bronchoconstictions. Regulation of human cation transporting ATPase can therefore be useful in preventing edema and modulating fluid levels in the lungs.

This invention further pertains to the use of novel agents identified by the screening assays described above. Accordingly, it is within the scope of this invention to use a test compound identified as described herein in an appropriate animal model. For example, an agent identified as described herein (e. g. , a modulating agent, an antisense nucleic acid molecule, a specific antibody, ribozyme, or a human cation transporting ATPase polypeptide binding molecule) can be used in an animal model to determine the efficacy, toxicity, or side effects of treatment with such an agent.

Alternatively, an agent identified as described herein can be used in an animal model to determine the mechanism of action of such an agent. Furthermore, this invention pertains to uses of novel agents identified by the above-described screening assays for treatments as described herein.

A reagent which affects cation transporting ATPase activity can be administered to a human cell, either in vitro or in vivo, to reduce cation transporting ATPase activity.

The reagent preferably binds to an expression product of a human cation transporting ATPase gene. If the expression product is a protein, the reagent is preferably an antibody. For treatment of human cells ex vivo, an antibody can be added to a preparation of stem cells that have been removed from the body. The cells can then

be replaced in the same or another human body, with or without clonal propagation, as is known in the art.

In one embodiment, the reagent is delivered using a liposome. Preferably, the liposome is stable in the animal into which it has been administered for at least about 30 minutes, more preferably for at least about 1 hour, and even more preferably for at least about 24 hours. A liposome comprises a lipid composition that is capable of targeting a reagent, particularly a polynucleotide, to a particular site in an animal, such as a human. Preferably, the lipid composition of the liposome is capable of targeting to a specific organ of an animal, such as the lung, liver, spleen, heart brain, lymph nodes, and skin.

A liposome useful in the present invention comprises a lipid composition that is capable of fusing with the plasma membrane of the targeted cell to deliver its contents to the cell. Preferably, the transfection efficiency of a liposome is about 0.5 pLg of DNA per 16 nmole of liposome delivered to about 106 cells, more preferably about 1. 0 llg of DNA per 16 nmole of liposome delivered to about 106 cells, and even more preferably about 2.0 llg of DNA per 16 nmol of liposome delivered to about 106 cells. Preferably, a liposome is between about 100 and 500 rim, more preferably between about 150 and 450 nm, and even more preferably between about 200 and 400 nm in diameter.

Suitable liposomes for use in the present invention include those liposomes standardly used in, for example, gene delivery methods known to those of skill in the art. More preferred liposomes include liposomes having a polycationic lipid composition and/or liposomes having a cholesterol backbone conjugated to polyethylene glycol. Optionally, a liposome comprises a compound capable of targeting the liposome to a particular cell type, such as a cell-specific ligand exposed on the outer surface of the liposome.

Complexing a liposome with a reagent such as an antisense oligonucleotide or ribozyme can be achieved using methods that are standard in the art (see, for example, U. S. Patent 5,705, 151). Preferably, from about 0.1 pg to about 10 llg of polynucleotide is combined with about 8 nmol of liposomes, more preferably from about 0.5 p, g to about zug of polynucleotides are combined with about 8 nmol liposomes, and even more preferably about 1.0 llg of polynucleotides is combined with about 8 nmol liposomes.

In another embodiment, antibodies can be delivered to specific tissues in vivo using receptor-mediated targeted delivery. Receptor-mediated DNA delivery techniques are taught in, for example, Findeis et al. Trends in Biotechnol. 11, 202-05 (1993); <BR> <BR> Chiou et al. , Gene Therapeutics: Methods and Applications of Direct Gene Transfer<BR> (J. A. Wolff, ed. ) (1994); Wu & Wu, J. Biol. Chem. 263,621-24 (1988); Wu et al. , J.<BR> <P>Biol. Chem. 269,542-46 (1994); Zenke et al. , Proc. Natl. Acad. Sci. U. S. A. 87,<BR> 3655-59 (1990); Wu et al. , J. Biol. Chem. 266, 338-42 (1991).

Determination of a therapeutically effective dose The determination of a therapeutically effective dose is well within the capability of those skilled in the art. A therapeutically effective dose refers to that amount of active ingredient which increases or decreases enzymatic activity relative to the enzymatic activity which occurs in the absence of the therapeutically effective dose.

For any compound, the therapeutically effective dose can be estimated initially either in cell culture assays or in animal models, usually mice, rabbits, dogs, or pigs. The animal model also can be used to determine the appropriate concentration range and route of administration. Such information can then be used to determine useful doses and routes for administration in humans.

Therapeutic efficacy and toxicity, e. g. , ED50 (the dose therapeutically effective in 50% of the population) and LD50 (the dose lethal to 50% of the population), can be determined by standard pharmaceutical procedures in cell cultures or experimental

animals. The dose ratio of toxic to therapeutic effects is the therapeutic index, and it can be expressed as the ratio, LD50/ED50.

Pharmaceutical compositions that exhibit large therapeutic indices are preferred. The data obtained from cell culture assays and animal studies is used in formulating a range of dosage for human use. The dosage contained in such compositions is preferably within a range of circulating concentrations that include the ED50 with little or no toxicity. The dosage varies within this range depending upon the dosage form employed, sensitivity of the patient, and the route of administration.

The exact dosage will be determined by the practitioner, in light of factors related to the subject that requires treatment. Dosage and administration are adjusted to provide sufficient levels of the active ingredient or to maintain the desired effect.

Factors that can be taken into account include the severity of the disease state, general health of the subject, age, weight, and gender of the subject, diet, time and frequency of administration, drug combination (s), reaction sensitivities, and tolerance/response to therapy. Long-acting pharmaceutical compositions can be administered every 3 to 4 days, every week, or once every two weeks depending on the half-life and clearance rate of the particular formulation.

Normal dosage amounts can vary from 0.1 to 100,000 micrograms, up to a total dose of about 1 g, depending upon the route of administration. Guidance as to particular dosages and methods of delivery is provided in the literature and generally available to practitioners in the art. Those skilled in the art will employ different formulations for nucleotides than for proteins or their inhibitors. Similarly, delivery of polynucleotides or polypeptides will be specific to particular cells, conditions, locations, etc.

If the reagent is a single-chain antibody, polynucleotides encoding the antibody can be constructed and introduced into a cell either ex vivo or in vivo using well- established techniques including, but not limited to, transferrin-polycation-mediated

DNA transfer, transfection with naked or encapsulated nucleic acids, liposome- mediated cellular fusion, intracellular transportation of DNA-coated latex beads, protoplast fusion, viral infection, electroporation, "gene gun, "and DEAE-or calcium phosphate-mediated transfection.

Effective in vivo dosages of an antibody are in the range of about 5 llg to about 50 ug/kg, about 50 llg to about 5 mg/kg, about 100 pg to about 500 llg/kg of patient body weight, and about 200 to about 250 llg/kg of patient body weight. For administration of polynucleotides encoding single-chain antibodies, effective in vivo dosages are in the range of about 100 ng to about 200 ng, 500 ng to about 50 mg, about 1 u. g to about 2 mg, about 5 llg to about 500 ug, and about 20 llg to about 100 llg of DNA.

If the expression product is mRNA, the reagent is preferably an antisense oligonucleotide or a ribozyme. Polynucleotides that express antisense oligonucleo- tides or ribozymes can be introduced into cells by a variety of methods, as described above.

Preferably, a reagent reduces expression of a human cation transporting ATPase gene or the activity of a cation transporting ATPase polypeptide by at least about 10, preferably about 50, more preferably about 75,90, or 100% relative to the absence of the reagent. The effectiveness of the mechanism chosen to decrease the level of expression of a human cation transporting ATPase gene or the activity of a human cation transporting ATPase polypeptide can be assessed using methods well known in the art, such as hybridization of nucleotide probes to cation transporting ATPase- specific mRNA, quantitative RT-PCR, immunologic detection of a human cation transporting ATPase polypeptide, or measurement of enzymatic activity.

In any of the embodiments described above, any of the pharmaceutical compositions of the invention can be administered in combination with other appropriate therapeutic agents. Selection of the appropriate agents for use in combination

therapy can be made by one of ordinary skill in the art, according to conventional pharmaceutical principles. The combination of therapeutic agents can act synergistically to effect the treatment or prevention of the various disorders described above. Using this approach, one may be able to achieve therapeutic efficacy with lower dosages of each agent, thus reducing the potential for adverse side effects.

Any of the therapeutic methods described above can be applied to any subject in need of such therapy, including, for example, mammals such as dogs, cats, cows, horses, rabbits, monkeys, and most preferably, humans.

. Diagnostic methods Human cation transporting ATPase also can be used in diagnostic assays for detecting diseases and abnormalities or susceptibility to diseases and abnormalities related to the presence of mutations in the nucleic acid sequences that encode the enzyme. For example, differences can be determined between the cDNA or genomic sequence encoding cation transporting ATPase in individuals afflicted with a disease and in normal individuals. If a mutation is observed in some or all of the afflicted individuals but not in normal individuals, then the mutation is likely to be the causative agent of the disease.

Sequence differences between a reference gene and a gene having mutations can be revealed by the direct DNA sequencing method. In addition, cloned DNA segments can be employed as probes to detect specific DNA segments. The sensitivity of this method is greatly enhanced when combined with PCR. For example, a sequencing primer can be used with a double-stranded PCR product or a single-stranded template molecule generated by a modified PCR. The sequence determination is performed by conventional procedures using radiolabeled nucleotides or by automatic sequencing procedures using fluorescent tags.

Genetic testing based on DNA sequence differences can be carried out by detection of alteration in electrophoretic mobility of DNA fragments in gels with or without

denaturing agents. Small sequence deletions and insertions can be visualized, for example, by high resolution gel electrophoresis. DNA fragments of different sequences can be distinguished on denaturing formamide gradient gels in which the mobilities of different DNA fragments are retarded in the gel at different positions <BR> <BR> according to their specific melting or partial melting temperatures (see, e. g. , Myers et al., Science 230,1242, 1985). Sequence changes at specific locations can also be revealed by nuclease protection assays, such as RNase and S 1 protection or the <BR> <BR> chemical cleavage method (e. g. , Cotton et al., Proc. Natl. Acad. Sci. USA 85, 4397-4401,1985). Thus, the detection of a specific DNA sequence can be performed by methods such as hybridization, RNase protection, chemical cleavage, direct DNA sequencing or the use of restriction enzymes and Southern blotting of genomic DNA.

In addition to direct methods such as gel-electrophoresis and DNA sequencing, mutations can also be detected by in situ analysis.

Altered levels of cation transporting ATPase also can be detected in various tissues.

Assays used to detect levels of the receptor polypeptides in a body sample, such as blood or a tissue biopsy, derived from a host are well known to those of skill in the art and include radioimmunoassays, competitive binding assays, Western blot analysis, and ELISA assays.

All patents and patent applications cited in this disclosure are expressly incorporated herein by reference. The above disclosure generally describes the present invention.

A more complete understanding can be obtained by reference to the following specific examples, which are provided for purposes of illustration only and are not intended to limit the scope of the invention.

EXAMPLE 1 Detection of cation transporting ATPase activity The polynucleotide of SEQ ID NO: 1 is inserted into the expression vector pCEV4 and the expression vector pCEV4-cation transporting ATPase polypeptide obtained is transfected into human embryonic kidney 293 cells. From these cells extracts are obtained and ATPase activity is measured as the liberation of 32Pi from [gamma- 32P] ATP. In general, samples are preincubated with or without 2.5 llg of designated phospholipid, for 10 min at 25°C. ATPase assay is started by the addition of 0.2 ml of assay solution consisting of 50 mM Tris-MES, pH 7.0, 30 mM KC1, 3 mM MgC12, and 3-5 mM [gamma-32P] ATP (400 cpm/nmol), with or without 0.1 mM sodium vanadate as an inhibitor, and incubated at 37°C for 30 min. The reaction is terminated by the addition of 1 ml of 1.25 N perchloric acid, and phosphate is extracted and counted in a scintillation counter. The results are expressed as nmol of Pi/min/assay, or calculated as llmol of Pi/min/mg of protein. It is shown that the polypeptide of SEQ ID NO: 2 has a cation transporting ATPase activity.

EXAMPLE 2 Expression of recombinant human cation transporting ATPase The Pichia pastoris expression vector pPICZB (Invitrogen, San Diego, CA) is used to produce large quantities of recombinant human cation transporting ATPase polypeptides in yeast. The cation transporting ATPase-encoding DNA sequence is derived from SEQ ID NO: 1. Before insertion into vector pPICZB, the DNA sequence is modified by well known methods in such a way that it contains at its 5'-end an initiation codon and at its 3'-end an enterokinase cleavage site, a His6 reporter tag and a termination codon. Moreover, at both termini recognition sequences for restriction endonucleases are added and after digestion of the multiple cloning site of pPICZ B with the corresponding restriction enzymes the modified DNA sequence is ligated into pPICZB. This expression vector is designed for

inducible expression in Pichia pastors, driven by a yeast promoter. The resulting pPICZ/md-His6 vector is used to transform the yeast.

The yeast is cultivated under usual conditions in 5 liter shake flasks and the recombinantly produced protein isolated from the culture by affinity chromatography (Ni-NTA-Resin) in the presence of 8 M urea. The bound polypeptide is eluted with buffer, pH 3.5, and neutralized. Separation of the polypeptide from the His6 reporter tag is accomplished by site-specific proteolysis using enterokinase (Invitrogen, San Diego, CA) according to manufacturer's instructions. Purified human cation transporting ATPase polypeptide is obtained.

EXAMPLE 3 Identification of test compounds that bind to cation transporting ATPase polypeptides Purified cation transporting ATPase polypeptides comprising a glutathione-S- transferase protein and absorbed onto glutathione-derivatized wells of 96-well microtiter plates are contacted with test compounds from a small molecule library at pH 7.0 in a physiological buffer solution. Human cation transporting ATPase polypeptides comprise the amino acid sequence shown in SEQ ID NO: 2. The test compounds comprise a fluorescent tag. The samples are incubated for 5 minutes to one hour. Control samples are incubated in the absence of a test compound.

The buffer solution containing the test compounds is washed from the wells.

Binding of a test compound to a human cation transporting ATPase polypeptide is detected by fluorescence measurements of the contents of the wells. A test compound that increases the fluorescence in a well by at least 15% relative to fluorescence of a well in which a test compound is not incubated is identified as a compound which binds to a human cation transporting ATPase polypeptide.

EXAMPLE 4 Identification of a test compound which decreases cation transporting ATPase gene expression A test compound is administered to a culture of human cells transfected with a cation transporting ATPase expression construct and incubated at 37°C for 10 to 45 minutes. A culture of the same type of cells that have not been transfected is incubated for the same time without the test compound to provide a negative control.

RNA is isolated from the two cultures as described in Chirgwin et al., Biochem. 18, 5294-99,1979). Northern blots are prepared using 20 to 30 llg total RNA and hybridized with a 32P-labeled cation transporting ATPase-specific probe at 65°C in Express-hyb (CLONTECH). The probe comprises at least 11 contiguous nucleotides selected from the complement of SEQ ID NO: 1. A test compound that decreases the cation transporting ATPase-specific signal relative to the signal obtained in the absence of the test compound is identified as an inhibitor of cation transporting ATPase gene expression.

EXAMPLE 5 <BR> <BR> Identification of a test compound which decreases cation transporting ATPase activity A test compound is administered to a culture of human cells transfected with a cation transporting ATPase expression construct and incubated at 37°C for 10 to 45 minutes. A culture of the same type of cells that have not been transfected is incubated for the same time without the test compound to provide a negative control.

Enzymatic activity is measured using the method of J Biochem Mol Toxicol 1999; 13 (2): 93-106.

A test compound which decreases the enzymatic activity of the cation transporting ATPase relative to the enzymatic activity in the absence of the test compound is identified as an inhibitor of cation transporting ATPase activity.

EXAMPLE 6 Tissue-specific expresszon of cation transporting ATPase In an analysis of cation transporting ATPase gene expression, 25 ug of total RNA from the following sources were used as template in reactions to synthesize first- strand cDNA for expression profiling: Human Total RNA Panel I-V (Clontech Laboratories, Palo Alto, CA, USA), normal human lung primary cell lines (BioWhittaker Clonetics, Walkersville, MD, USA), human umbilical vein endothelial cells (HUVECs) (Kurabo, Osaka, Japan), several common cell lines (ATCC, Washington, DC), and various cells purified from peripheral blood. First- strand cDNA was synthesized using oligo (dT) (Nippon Gene Research Laboratories, Sendai, Japan) and the SUPERSCRIPTTM First-Strand Synthesis System for RT-PCR (Life Technologies, Rockville, MD) according to the manufacturer's protocol. For these samples, 1/1250th of the synthesized first-strand cDNA was subsequently used as template for quantitative PCR. Additional samples were purchased as presynthesized cDNAs (Human Immune System MTC Panel and Human Blood Fractions MTC Panel, Clontech Laboratories), and for these, 10 ng of cDNA was e used as template for quantitative PCR.

Quantitative PCR was performed in a LightCycler (Roche Molecular Biochemicals, Indianapolis, IN) with oligonucleotide primers LBRI582-L3 (5'- GGGCAGAAGTCCAGTCTGGTGGAA-3') and LBRI582-R3 (5'- ACGAGAGCTGCACGTCCTTCCTTG-3') in the presence of the DNA-binding fluorescent dye SYBR Green I. Results were then converted into copy numbers of the gene transcript per ng of template cDNA by fitting to a standard curve. The standard curve was derived by simultaneously performing the quantitative PCR reaction on PCR products of known concentrations amplified beforehand from the target gene.

To correct for differences in mRNA transcription levels per cell in the various tissue types, a normalization procedure was performed using similarly calculated expression levels of five different housekeeping genes : glyceraldehyde-3-phosphatase (G3PDH), hypoxanthine guanine phophoribosyl transferase (HPRT), beta-actin, porphobilinogen deaminase (PBGD), and beta-2-microglobulin. The level of housekeeping gene expression is considered to be relatively constant for all tissues (Adams et al. , 1993, Adams et al. , 1995, Liew et al. , 1994) and therefore can be used as a gauge to approximate relative numbers of cells per ng of cDNA template.

Expression levels of the five housekeeping genes in all tissue samples were measured in three independent reactions per gene using the LightCycler and a constant amount (25 u. g) of starting RNA. The calculated copy numbers for each gene, derived from comparison with simultaneously reacted standards of known concentrations, were recorded and converted into a percentage of the sum of the copy numbers of the gene in all tissue samples. For each tissue sample, the sum of the percentage values for each gene was calculated, and a normalization factor was calculated by dividing the sum percentage value for each tissue by the sum percentage value of one of the tissues arbitrarily selected as a standard. To normalize an experimentally obtained value for the expression of a particular gene in a tissue sample, the obtained value was multiplied by the normalization factor for the tissue tested. This normalization method was used for all tissues except those derived from the Human Blood Fractions MTC Panel, which were normalized against the single housekeeping gene, beta-2-microglobulin, due to wide variation in other housekeeping gene expression in these tissues depending on activation status. The results of this expression profiling are given in Figure 11, showing the normalized values for the copy numbers of mRNA per 10 ng of first-strand cDNA in each sample tested.

EXAMPLE 7 In vivo testing of compounds/target validation for asthma treatment

Tests for activity of T cells Mouse anti-CD3 induced cvtokine production model BALB/c mice are injected with a single intravenous injection of 10 llg of 145-2C11 (purified hamster anti-mouse CD3£ monoclonal antibodies, PHARMINGEN). A test compound is administered intraperitoneally 60 min prior to the anti-CD3 mAb injection. Blood is collected 90 minutes after the antibody injection. Serum is obtained by centrifugation at 3000 r. p. m. for 10 min. IL-2 and IL-4 levels in the serum are determined by an ELISA.

Tests for activity of B cells Mouse anti-IW induced IgE production model BALB/c mice are injected intravenously with 0.8 mg of purified goat anti-mouse IgD, antibody or PBS (defined as day 0). Compound is administered intraperitoneally from day 0 to day 6. On day 7 blood is collected and serum is obtained by centrifugation at 3000 r. p. m. for 10 min. Serum total levels of IgE are determined by YAMASA's ELISA kit and their Ig subtypes are done by an Ig ELISA KIT (Rougier Biotech's, Montreal, Canada).

Tests for activity, of monocytes/macrophages Mouse LPS-induced TNF-a production model BALB/c mice are injected intraperitoneally with LPS (200 u. g/mouse). Compound is administered intraperitoneally 1 hr before the LPS injection. Blood is collected at 90 min post-LPS injection and plasma is obtained. TNF-a concentration in the sample is determined using an ELISA kit.

Tests eosinophil activation Mouse eotaxin-induced eosinophilia model BALB/c mice are injected intradermally with a 2.5 ml of air on days-6 and-3 to prepare airpouch. On day 0 compound is administered intraperitoneally 60 min before eotaxin injection (3 pg/mouse, i. d. ). IL-5 (300 ng/mouse) is injected

intravenously 30 min before the eotaxin injection. After 4 hr of the eotaxin injection leukocytes in exudate is collected and the number of total cells is counted. The differential cell counts in the exudate are performed by staining with May-Grunwald Gimsa solution.

Tests activation of Th2 cells Mouse DIO cell transfer model D10. G4.1 cells (1 x 107 cells/mouse) containing 2 mg of conalbumin in saline is administered i. v. to AKR mice. After 6 hr blood is collected and serum is obtained by centrifugation at 3000 r. p. m. for 10min. IL-4 and IL-5 level in serum are determined by ELISA kits. Compound is administered intraperitoneally at-4 and +1 hr after these cells injection.

Passive cutaneous anaphylaxis (PCA) test in rats- <BR> <BR> 6 Weeks old male Wistar rats are sensitized intradermally (i. d. ) on their shaved backs with 50 gel of 0.1 llg/ml mouse anti-DNP IgE monoclonal antibody (SPE-7) under a light anesthesia. After 24 hours, the rats are challenged intravenously with 1 ml of <BR> <BR> saline containing 0.6 mg DNP-BSA (30) (LSL CO. , LTD) and 0.005 g of Evans blue.<BR> <P>Compounds are injected intraperitoneally (i. p. ) 0.5 hr prior to antigen injection. Rats without the sensitization, challenge, and compound treatment are used for a blank (control) and rats with sensitization, challenge and vehicle treatment are used to determine a value without inhibition. Thirty min after the challenge, the rats are killed, and the skin of the back is removed. Evans blue dye in the skin is extracted in formamide overnight at 63°C. Then an absorbance at 620 nm is measured to obtain the optical density of the leaked dye.

Percent inhibition of PCA with a compound is calculated as follows: % inhibition = { (mean vehicle value-sample value)/ (mean vehicle value-mean control value)} x 100

Anaphylactic bronchoconstriction in rats 6 Weeks old male Wistar rats are sensitized intravenously (i. v. ) with 10 u. g mouse anti-DNP IgE, SPE-7, and 1 days later, the rats are challenged intravenously with 0.3 ml of saline containing 1.5 mg DNP-BSA (30) under anesthesia with urethan (1000 mg/kg, i. p. ) and gallamine (50 mg/kg, i. v. ). The trachea is cannulated for artificial respiration (2 ml/stroke, 70 strokes/min). Pulmonary inflation pressure (PIP) is recorded through a side-arm of cannula connected to pressure transducer. Change in PIP reflects change of both resistance and compliance of the lungs. To evaluate the drugs, each drug is given i. v. 5 min before challenge.

REFERENCES Structure of a Plasmodium yoelii gene-encoded protein homologous to the Ca (2+)- ATPase of rabbit skeletal muscle sarcoplasmic reticulum, Murakami K, Tanabe K, Takada S, J Cell Sci 1990 Nov; 97 (Pt 3): 487-95 Analysis of a cation-transporting ATPase of Plasmodium falciparum, Dyer M, Jackson M, McWhinney C, Zhao G, Mikkelsen R,. Mol Biochem Parasitol 1996 Jun; 78 (1-2) : 1-12 The influence of the membrane sodium pump activity on the ability of human peripheral blood lymphocytes to form early rosettes with SRBC, Witkowski J, Immunology 1985 Jun; 55 (2): 339-45.

Effect of lithium and of other drugs used in the treatment of manic illness on the cation-transporting properties of Na+, K+-ATPase in mouse brain synaptosomes, Wood AJ, Elphick M, Grahame-Smith DG, J Neurochem 1989 Apr; 52 (4): 1042-9