Enables enzyme binding activity and protein-macromolecule adaptor activity. Involved in several processes, including phosphatidylserine metabolic process; positive regulation of CDP-diacylglycerol-serine O-phosphatidyltransferase activity; and positive regulation of serine C-palmitoyltransferase activity. Located in endoplasmic reticulum membrane and plasma membrane. Orthologous to human SERINC1 (serine incorporator 1). [provided by Alliance of Genome Resources, Apr 2022]