Catalyzes the transport of triglyceride, cholesteryl ester, and phospholipid between phospholipid surfaces (   , ). Required for the assembly and secretion of plasma lipoproteins that contain apolipoprotein B (  ). May be involved in regulating cholesteryl ester biosynthesis in cells that produce lipoproteins (By similarity).
Subcellular locations: Endoplasmic reticulum, Golgi apparatus
Colocalizes with P4HB/PDI in the endoplasmic reticulum (, ).
Liver and small intestine. Also found in ovary, testis and kidney.