Involved in GM1/GD1B/GA1 ganglioside biosynthesis. ganglioside GM2 (d18:1(4E)) + UDP-alpha-D-galactose = ganglioside GM1 (d18:1(4E)) + H(+) + UDP ganglioside GM2 + UDP-alpha-D-galactose = ganglioside GM1 + H(+) + UDP ganglioside GD2 (d18:1(4E)) + UDP-alpha-D-galactose = ganglioside GD1b (d18:1(4E)) + H(+) + UDP ganglioside GA2 (d18:1(4E)) + UDP-alpha-D-galactose = ganglioside GA1 (d18:1(4E)) + H(+) + UDP Protein modification; protein glycosylation. Highly expressed in heart, skeletal muscle and pancreas and, to a lesser extent, in brain, placenta, kidney, liver and lung. Belongs to the glycosyltransferase 31 family. Beta-1,3-galactosyltransferase 4