XylT-I Background Information
Xylosyltransferase-I (XylT-I), also designated UDP-D-xylose:proteoglycan core protein b-D-xylosyltransferase 1, is a glycoprotein that catalyzes the transfer of UDP-xylose to serine residues within XT recognition sequences of target proteins. Addition of xylose to the core protein is a requirement for the biosynthesis of the glycosaminoglycan chains that are characteristic of proteoglycans. Xylosyltransferase proteins, which can be secreted, display activity in sternal cartilage chondrocytes, chondrosarcoma, nasal septum tumor and choriocarcinoma cells. XYlT-I is widely expressed, with higher levels of expression detected in placenta, kidney and pancreas, and lower levels of expression observed in skeletal muscle. Xylosyltransferase-II (XylT-II), also designated UDP-D-xylose:proteoglycan core protein b-D-xylosyltransferase 2, is also widely expressed, with higher levels of expression detected in kidney and pancreas.
