Predicted to enable L-serine-phosphatidylcholine phosphatidyltransferase activity and L-serine-phosphatidylethanolamine phosphatidyltransferase activity. Predicted to be involved in phosphatidylserine biosynthetic process. Predicted to act upstream of or within phospholipid biosynthetic process. Predicted to be located in endoplasmic reticulum membrane. Human ortholog(s) of this gene implicated in Lenz-Majewski hyperostotic dwarfism. Orthologous to human PTDSS1 (phosphatidylserine synthase 1).