OSBPL3

This gene encodes a member of the oxysterol-binding protein (OSBP) family, a group of intracellular lipid receptors. Most members contain an N-terminal pleckstrin homology domain and a highly conserved C-terminal OSBP-like sterol-binding domain. The encoded protein is involved in the regulation of cell adhesion and organization of the actin cytoskeleton. Alternative splicing results in multiple transcript variants.

Oxysterol Binding Protein Like 3

Phosphoinositide-binding protein which associates with both cell and endoplasmic reticulum (ER) membranes (PubMed:16143324).
Can bind to the ER membrane protein VAPA and recruit VAPA to plasma membrane sites, thus linking these intracellular compartments (PubMed:25447204).
The ORP3-VAPA complex stimulates RRAS signaling which in turn attenuates integrin beta-1 (ITGB1) activation at the cell surface (PubMed:18270267, PubMed:25447204).
With VAPA, may regulate ER morphology (PubMed:16143324).
Has a role in regulation of the actin cytoskeleton, cell polarity and cell adhesion (PubMed:18270267).
Binds to phosphoinositides with preference for PI(3,4)P2 and PI(3,4,5)P3 (PubMed:16143324).
Also binds 25-hydroxycholesterol and cholesterol (PubMed:17428193).

Bile acid biosynthetic processTAS:Reactome

Endoplasmic reticulum membrane
Cytoplasm, cytosol
Cell membrane
Cell projection, filopodium tip
Nucleus membrane
Co-localizes with OSBPL6 at contact sites between the plasma membrane and the endoplasmic reticulum.

Phosphorylation is enhanced in vitro by phorbol-12-myristate-13-acetate (PMA), forskolin and calcium ionophore A23187 (PubMed:25447204).
Phosphorylation seems to be stimulated in conditions of low cell-cell (or cell-matrix) adhesion (PubMed:18270267).