Molecular cloning and characterization of stanniocalcin-related protein.

Stanniocalcin (STC) is a glycoprotein hormone first discovered in fish and recently identified in humans and mice. In this report we have described the cloning of an STC-like cDNA, designated here as STC related protein (STCrP). Human STCrP (hSTCrP) cDNAs were isolated as expressed sequence tags (ESTs) and predicted a polypeptide of 302 amino acids, with 58%, homology to human STC (hSTC). Ten of the eleven 1/2 cysteine residues that in STC allow for dimerization of monomeric subunits were conserved in hSTCrP. By Northern analysis, three hSTCrP mRNAs were detected and were most abundant in pancreas, spleen and kidney as well as a variety of different transformed cell lines. The high degree of sequence homology suggests that STC and STCrP may have been derived from a common ancestral gene.