To obtain a new reporter gene-constructing substance consisting of a multiple responding element, a cAMP responding element, a vasointestinal peptide promotor and a receptor gene, and useful for assay of a compound related to a cell surface localized receptor, etc.

This new reporter gene-constructing substance comprises (A) a multiple responding element, (B) a cAMP responding element, (C) a vasointestinal peptide promotor and (D) a receptor gene, and useful for assay of a compound on an agonistic or an antagonistic activity thereof related to a receptor localized at the surface of cells. The reporter gene is obtained by joining one or more multiple responding elements such as an interleukin-6 multiple responding element, etc., with a vasointestinal peptide promoter, a cyclic- AMP responding enhancer element and a receptor gene, etc.