Molecular cloning and characterization of chondroitin 6-sulfotransferase (c6st) in crush-injured rat sciatic nerves

Abstract

Our earlier results indicated upregulated expression of chondroitin 6-sulfotransferase (C6ST) in crushed nerves and thus provided suggestion for the cause of increase of chondroitin 6 sulfate isoforms in the crushed nerve environment. To verify this, we cloned the full length C6ST from RNAs recovered from injured rat sciatic nerves. Sequencing results predicted a protein of 474 amino acids with homologies of 84% and 93% to those of human and mouse C6ST respectively. Transient transfection of expression constructs carrying either the full-length or a truncated isoform of C6ST into COS-7 cells resulted in increased C6ST activity in the cell homogenates. The recombinant C6ST was verified to transfer sulfate to carbon-6 of N-acetylgalactosamine residues of chondroitin. In situ hybridization with DIG-labeled C6ST cRNA probe revealed positive signals in Schwann cells and increased signals in crushed sciatic nerves, suggesting a functional role in nerve regeneration. (SPON: The Hong Kong Society of Neurosciences). Supported by HKU 7294/01M