Predicted to enable glycoprotein-N-acetylgalactosamine 3-beta-galactosyltransferase activity. Acts upstream of or within platelet activation; platelet morphogenesis; and protein O-linked glycosylation. Predicted to be located in membrane. Predicted to be integral component of membrane. Human ortholog(s) of this gene implicated in Tn polyagglutination syndrome. Orthologous to human C1GALT1C1 (C1GALT1 specific chaperone 1). [provided by Alliance of Genome Resources, Apr 2022]