Enables glycosyltransferase activity. Acts upstream of or within several processes, including chondroitin sulfate biosynthetic process; positive regulation of smoothened signaling pathway; and skeletal system development. Predicted to be located in extracellular region. Is expressed in several structures, including alimentary system; brain; cranium; ear; and respiratory system. Human ortholog(s) of this gene implicated in temtamy preaxial brachydactyly syndrome. Orthologous to human CHSY1 (chondroitin sulfate synthase 1). [provided by Alliance of Genome Resources, Apr 2022]