GPIHBP1

Dietary fats are packaged by intestine into triglyceride-rich lipoproteins called chylomicrons. The triglycerides in chylomicrons are hydrolyzed by lipoprotein lipase (LPL: MIM 609708) along the luminal surface of capillaries, mainly in heart, skeletal muscle, and adipose tissue. GPIHBP1 is a capillary endothelial cell protein that provides a platform for LPL-mediated processing of chylomicrons (Beigneux et al., 2007 [PubMed 17403372]).[supplied by OMIM

Full Name

glycosylphosphatidylinositol anchored high density lipoprotein binding protein 1

Function

Mediates the transport of lipoprotein lipase LPL from the basolateral to the apical surface of endothelial cells in capillaries (By similarity).

Anchors LPL on the surface of endothelial cells in the lumen of blood capillaries (By similarity).

Protects LPL against loss of activity, and against ANGPTL4-mediated unfolding (PubMed:27929370, PubMed:29899144).

Thereby, plays an important role in lipolytic processing of chylomicrons by LPL, triglyceride metabolism and lipid homeostasis (PubMed:19304573, PubMed:21314738).

Binds chylomicrons and phospholipid particles that contain APOA5 (PubMed:17997385, PubMed:19304573).

Binds high-density lipoprotein (HDL) and plays a role in the uptake of lipids from HDL (By similarity).

Biological Process

Cholesterol homeostasis Source: BHF-UCL
Intracellular protein transport Source: BHF-UCL
Positive regulation of chylomicron remnant clearance Source: BHF-UCL
Positive regulation of lipoprotein lipase activity Source: ARUK-UCL
Protein import Source: BHF-UCL
Protein localization to cell surface Source: BHF-UCL
Protein stabilization Source: ARUK-UCL
Response to heparin Source: BHF-UCL
Transcytosis Source: BHF-UCL
Triglyceride homeostasis Source: BHF-UCL

Cellular Location

Apical cell membrane; Basolateral cell membrane; Cell membrane

Involvement in disease

Hyperlipoproteinemia 1D (HLPP1D):
An autosomal recessive disorder characterized by hyperlipoproteinemia, decreased plasma LPL levels in some patients, high plasma triglyceride levels, and refractory fasting chylomicronemia.

PTM

Glycosylation of Asn-78 is critical for cell surface localization.By similarity
Sulfation of a Tyr in the N-terminal acidic region increases the affinity for LPL.