2.4.1.135	malfunction	dGlcAT-P null mutants larvae show lower expression of glucuronylated T antigen on the muscles and at neuromuscular junctions (NMJs). Mislocalization of NMJ boutons and a partial loss of the basement membrane components collagen IV (Col IV) and nidogen (Ndg) at the muscle 6/7 boundary are observed. The phenotypes correlate to previously described phenotypes in dC1GalT1 mutant larvae. dGlcAT-P null mutants exhibit fewer NMJ branches on muscles 6/7 compared to wild-type. Basement membranes that lack Col IV and Ndg are significantly deformed. The loss of dGlcAT-P expression causes ultrastructural defects in NMJ boutons. Genetic interaction between dGlcAT-P and dC1GalT1 is determined. Phenotypes of dGlcAT-P mutants, detailed overview	759109	
2.4.1.135	metabolism	genetic interaction between dGlcAT-P and dC1GalT1 (EC 2.4.1.122), and glucuronylated T antigen, rather than unmodified T antigen, contributes to precise localization of NMJ boutons and normal formation of basement membranes on muscles 6/7. Glucuronylated core 1 glycans synthesized by dGlcAT-P are key modulators of neuromuscular junction (NMJ) bouton localization, basement membrane formation, and NMJ arborization on larval muscles. In Drosophila, three major mucin-type O-glycan structures, i.e. Tn antigen (GalNAcalpha1-Ser/Thr), unmodified T antigen (core 1 or Galbeta1-3GalNAcalpha1-Ser/Thr), and glucuronylated T antigen (glucuronylated core 1 or GlcAbeta1-3Galbeta1-3GalNAcalpha1-Ser/Thr), have been reported. And three Drosophila beta1,3-glucuronyltransferases (dGlcATs), dGlcAT-I (DmGlcAT-I), dGlcAT-S (DmGlcAT-BSI), and dGlcAT-P (DmGlcAT-BSII), have been reported in Drosophila. Both dGlcAT-P and dGlcAT-S can transfer GlcA to T antigen in vitro, whereas only dGlcAT-P modifies T antigen in S2 cells	759109	
2.4.1.135	metabolism	the enzyme is a key regulator and rate-limiting enzyme for the synthesis of GAG chains	721257	
2.4.1.135	additional information	gene B3GAT3 is a unigene, pathway enrichment analysis of assembled unigenes, overview. Identification of markers of NK cells. Enzyme structure modelling using the structure of human GlcAT-P as a template	737068	
2.4.1.135	physiological function	the enzyme mediates a glucuronyl transfer reaction during the biosynthesis of the carbohydrate epitope HNK-1, human natural killer-1, also known as CD57, a marker of NK cells	737068	
2.4.1.135	physiological function	the major components of basement membrane are proteins modified by glycans. In Drosophila, glucuronylation of T antigen is predominantly carried out by Drosophila beta1,3-glucuronyltransferase-P (dGlcAT-P). T antigen formation occurs mainly due to the activity of Drosophila C1GalT1 orthologue	759109