Carbohydrate sulfotransferase 10 (CHST10) transfers sulfate (SO4(2-)) from the high energy donor 3'-phospho-5'-adenylyl sulfate (PAPS) to position 3 of non-reducing glucuronyl (GlcA) residues of N-glycosylated proteins terminating with the saccharide sequence glucuronyl-lactosaminyl (GlcA-LacN), forming the HNK1 carbohydrate (sulfo-3GlcA-beta1,3Gal-beta1,4-GlcNAc-R). The HNK1 carbohydrate is expressed on various adhesion molecules (neural cells, natural killer cells) in the nervous system and may play a role in cell-cell and cell-substratum interactions (Ong et al. 1998, 1999).