• B4GALT1 is a member of the β-1, 4-galactosyltransferase family, which has membrane and secretory isoforms. B4GALT1 is a widely studied glycosyltransferase, a type II membrane-bound glycoprotein that transfers galactose from uridine diphosphate galactose (UDP-Gal) to a specific glycoprotein substrate. B4GALT1 is distributed in the Golgi apparatus, some cell surfaces, and body fluids in vivo. B4GALT1 in the Golgi apparatus catalyzes the formation of β-1, 4-glucoside bonds between galactose and N-acetylglucosamine. B4GALT1 on the cell surface is a cell adhesion molecule involved in cell-matrix and cell-cell interactions. The deficiency of B4GALT1 is the cause of 2D congenital disorders of glycosylation. In IgA nephropathy, the B4GALT1 expression in glomerular is increased.
• Protein expression analysis: B4GALT1 was detectable in liver, kidney and colon of both homozygous B-hB4GALT1 mice and wild-type mice, as anti-B4GALT1 antibody was cross-reactive between human and mouse.
• mRNA expression analysis: Mouse B4galt1 was only detectable in kidney of wild-type C57BL/6 mice. Human B4GALT1 was detectable in kidney of homozygous B-hB4GALT1 mice. 

Western blot analysis of B4GALT1 protein expression in homozygous B-hB4GALT1 mice. Various tissue lysates were collected from wild-type C57BL/6 mice (+/+) and homozygous B-hB4GALT1 mice (H/H), and then analyzed by western blot with cross reactive anti-B4GALT1 antibody (Abcam ab121326). 40 μg total proteins were loaded for western blotting analysis. B4GALT1 was detected in liver, kidney and colon of both homozygous B-hB4GALT1 mice and wild-type mice.

Strain specific analysis of B4GALT1 mRNA expression in wild-type C57BL/6 mice and B-hB4GALT1 mice by RT-PCR. Kidney RNA were isolated from wild-type C57BL/6 mice (+/+) and homozygous B-hB4GALT1 mice (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse or human B4GALT1 primers. Mouse B4galt1 mRNA was detectable in wild-type mice. Human B4GALT1 mRNA was detectable only in homozygous B-hB4GALT1 mice but not in wild-type mice.