Functional expression and genomic structure of human chondroitin 6‐sulfotransferase1

The cDNA and gene encoding human chondroitin 6-sulfotransferase (C6ST) have been cloned. The expression of a soluble recombinant form of the protein in COS-1 cells produced an active sulfotransferase, which used as acceptor substrates polymer chondroitin, various chondroitin sulfate isoforms and chondroitin sulfate tetrasaccharides. The identification of the reaction products demonstrated that the enzyme transferred sulfate to position 6 of GalNAc in the GlcAbeta1-3GalNAc but not the IdoAalpha1-3GalNAc nor the GlcAbeta1-3GalNAc(4-O-sulfate) sequences. The human C6ST gene spans more than 20 kb and consists of three exons. The protein-coding domain of the C6ST gene is divided into two discrete exons.