Has both beta-1,3-glucuronic acid and beta-1,4-N-acetylgalactosamine transferase activity (PubMed:12761549). The beta-1,3-glucuronic acid transferase activity is controversial as it is not detected using the purified recombinant enzyme (PubMed:12761550). Adds the first N-acetylgalactosamine(GalNAc) to initiate the chondroitin chain. Transfers glucuronic acid (GlcUA) from UDP-GlcUA and GalNAc from UDP-GalNAc to the non-reducing end of the elongating chondroitin polymer (PubMed:12761549, PubMed:12761550). Together with mig-22, required for chondroitin synthesis (PubMed:15485872). Plays a role in early embryonic development by controlling cell division and cytokinesis (PubMed:12761550). In addition, involved in vulva morphogenesis and in the directed migration of gonadal distal tip cells and hermaphrodite specific neurons (PubMed:12761549, PubMed:16982046, PubMed:24052309). May be required for nunc6/netrin-mediated dorsal guidance of distal tip cells (PubMed:16982046). 3-O-(beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + UDP-N-acetyl-alpha-D-galactosamine = 3-O-(beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + H(+) + UDP 3-O-(beta-D-GlcA-(1->3)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + UDP-N-acetyl-alpha-D-galactosamine = 3-O-(beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + H(+) + UDP 3-O-(beta-D-GlcA-(1->3)-[beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)](n)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + UDP-N-acetyl-alpha-D-galactosamine = 3-O-([beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)](n+1)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + H(+) + UDP 3-O-(beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + UDP-alpha-D-glucuronate = 3-O-(beta-D-GlcA-(1->3)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + H(+) + UDP 3-O-([beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)](n)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + UDP-alpha-D-glucuronate = 3-O-(beta-D-GlcA-(1->3)-[beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)](n)-beta-D-GalNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + H(+) + UDP Interacts with mig-22. Localizes in punctate foci in the cytoplasm. Co-localizes with sqv-1. Expressed in vulva, uterus and oocytes. Mutant hermaphrodites have a defect in the invagination of the vulva epithelium and produce fewer eggs (PubMed:12761549). A similar defect is observed in RNAi-mediated knockdown (PubMed:12761550). In addition, RNAi-mediated knockdown in embryos shows severe cell division defects including cytokinesis reversal and increased number of nuclei per cell resulting in early embryonic death in utero (PubMed:12761550). RNAi-mediated knockdown in adults shows a normal sperm production (PubMed:12761550). Belongs to the chondroitin N-acetylgalactosaminyltransferase family.