Xylosyltransferases catalyze the attachment of xylose, first linker sugar residue, to a major group of extracellular matrix proteins, namely proteoglycans, and are therefore of key importance for proper PG biosynthesis in many tissues (PMID: 26027496). XYLT2 (xylosyltransferase II, XylT-II) is a protein homologous to XYLT1 but with hitherto unknown activity or physiological function. In most tissues, both xylosyltransferase genes are expressed and in numerous cell lines XYLT2 is the major xylosyltransferase (PMID: 17189265, 25748573).