PITPNB
Function
Catalyzes the transfer of phosphatidylinositol and phosphatidylcholine between membranes (PubMed:10531358, PubMed:18636990, PubMed:20332109). Also catalyzes the transfer of sphingomyelin (By similarity). Required for COPI-mediated retrograde transport from the Golgi to the endoplasmic reticulum; phosphatidylinositol and phosphatidylcholine transfer activity is essential for this function (PubMed:20332109).
Post-translational modifications
Constitutive phosphorylation of Ser-262 has no effect on phospholipid transfer activity but is required for Golgi targeting.
Sequence Similarities
Belongs to the PtdIns transfer protein family. PI transfer class I subfamily.
Tissue Specificity
Widely expressed in various tissues including brain.
Cellular localization
- Golgi apparatus
- Golgi apparatus membrane
- Endoplasmic reticulum membrane
Alternative names
Phosphatidylinositol transfer protein beta isoform, PI-TP-beta, PtdIns transfer protein beta, PtdInsTP beta, PITPNB