Core-1-Synthase, Glycoprotein-N-Acetylgalactosamine-3-Beta-Galactosyltransferase 1 (C1GALT1)

C1GALT1 is associated with the T-Tn antigen system.The C1GALT1 gene encodes a 363-amino acid type II transmembrane protein. Northern blot analysis demonstrated widespread expression of human core 1 beta-3-Gal-T, with predominance in kidney, heart, placenta, and liver.Transfection assays of 293T cells showed that overexpression of active C1GALT1 also requires overexpression of C1GALT1C1. Nickel-affinity binding of His-tagged recombinant C1GALT1C1 demonstrated that C1GALT1C1 directly associates with C1GALT1. Assays on transfected Jurkat cells showed that the endogenous C1GALT1 mutation in Jurkat cells is complemented by C1GALT1C1, restoring C1GALT1 function and biosynthesis of core 1 O-glycans, and generating active, soluble, and secreted C1GALT1 protein.