Chondroitin sulfate N-acetylgalactosaminyltransferase-1 is required for normal cartilage development.

Niigata University, Chuo-ku, Japan.
Biochemical Journal (Impact Factor: 4.65). 11/2010; 432(1):47-55. DOI: 10.1042/BJ20100847
Source: PubMed

ABSTRACT CS (chondroitin sulfate) is a glycosaminoglycan species that is widely distributed in the extracellular matrix. To understand the physiological roles of enzymes involved in CS synthesis, we produced CSGalNAcT1 (CS N-acetylgalactosaminyltransferase 1)-null mice. CS production was reduced by approximately half in CSGalNAcT1-null mice, and the amount of short-chain CS was also reduced. Moreover, the cartilage of the null mice was significantly smaller than that of wild-type mice. Additionally, type-II collagen fibres in developing cartilage were abnormally aggregated and disarranged in the homozygous mutant mice. These results suggest that CSGalNAcT1 is required for normal CS production in developing cartilage.

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