Predicted to enable glucuronosyl-N-acetylgalactosaminyl-proteoglycan 4-beta-N-acetylgalactosaminyltransferase activity. Predicted to be involved in chondroitin sulfate biosynthetic process. Orthologous to human CHPF2 (chondroitin polymerizing factor 2). [provided by Alliance of Genome Resources, Apr 2022]