To specify the amino acid sequence of a dynamic control factor protein of a cytoskeleton of neurocyte resembling coronine and p57 and the base sequence of a polynucleotide coding for the protein.

A gene coding for a dynamic control factor protein of a cytoskeleton of a neurocyte resembling coronine or p57 is identified by the screening of a uniformized DNA library using an mRNA originated from human cerebrum and the protein coded by the gene is identified. Three are also provided the protein, a protein consisting of a modification, variation or a part of the gene and a polynucleotide. The protein and the gene can be used for the dynamic control of the cytoskeleton of neurocyte, investigation of physiological function such as the development of neurite, formation and recombination of synapse, etc., treatment of degenerative diseases of neurocyte caused by the abnormality of the function, agent for the treatment, diagnosis of the diseases and diagnostic agent, etc.