Human Ryudocan Core Protein: Molecular Cloning and Characterization of the cDNA, and Chromosomal Localization of the Gene

Abstract

We have isolated a series of overlapping cDNA clones encoding a 2,628 bp transcript, which potentially codes for a 198 amino acid protein with predicted molecular mass of 21,641 daltons, for the human ryudocan core protein. The deduced core proteins of the human and the rat ryudocan have high structural conservation, particularly in the NH 2 and COOH terminus regions of the putative mature core protein, including the combined transmembrane/cytoplasmic domains with conserved positions of all 4 tyrosine groups and 3 conserved glycosaminoglycan chain attachment regions, which might serve important roles for biological function of ryudocan. A major 2.7 kb transcript was detected in all tissues tested, with relatively high levels of expression observed in mRNA from lung, liver, skeletal muscle and kidney. A minor 1.9 kb transcript was also observed in some of tissues, which would be caused by alternative polyadenylation. Human ryudocan gene has been localized on the chromosome 20q12 by fluorescence in situ hybridization.