First Comprehensive In Silico Analysis of the Functional and Structural Consequences of SNPs in Human GalNAc-T1 Gene

Figure 7

Complex structure of GalNAc-T1 enzyme with UDP, MUC1 (tandem repeat region “GSTAPPAHGVTSAP”), and GalNAc residue. GalNAc sugar is attached at Thr of tandem repeat region in MUC1. His125 and Asp156 residues from catalytic A domain and Ile315, Trp316, and Thr350 from catalytic B domain are found in contact with UDP (orange red color). Under the action of ST6GALNAC1, B4GALNT1, C1GALT1C1, C1GALT1, GCNT1, and B3GNT6, GalNAc1-O-Thr is stereospecifically converted into different glycan chains to regulate the mucin biosynthesis pathway.