SCUBA

ABCB4 — ATP binding cassette subfamily B member 4

ABCB4 belongs to a gene co-expression module in 1 of 28 SCUBA cell types. Each module groups genes that rise and fall together in that cell type; the genes it shares a module with are its closest co-expression partners there.

ABCB4's module in each cell type

Cell typeModuleShares the module with
CD19⁺ B cellsNaive B cell
B cell maturation
ABCB1, BTLA, C1orf162, CD200, COL19A1, DSP, FCER2, IGHD +15 moreView in SCUBA

About the gene

SynonymsGBD1, MDR2, MDR3, PFIC-3, PGY3
Chromosome7: 87401696-87480435
Predicted locationIntracellular, Membrane
Essential geneNo
Protein classDisease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters
Molecular functionTranslocase
Biological processLipid transport, Transport

Function

Energy-dependent phospholipid efflux translocator that acts as a positive regulator of biliary lipid secretion. Functions as a floppase that translocates specifically phosphatidylcholine (PC) from the inner to the outer leaflet of the canalicular membrane bilayer into the canaliculi of hepatocytes. Translocation of PC makes the biliary phospholipids available for extraction into the canaliculi lumen by bile salt mixed micelles and therefore protects the biliary tree from the detergent activity of bile salts. Plays a role in the recruitment of phosphatidylcholine (PC), phosphatidylethanolamine (PE) and sphingomyelin (SM) molecules to nonraft membranes and to further enrichment of SM and cholesterol in raft membranes in hepatocytes. Required for proper phospholipid bile formation (By similarity). Indirectly involved in cholesterol efflux activity from hepatocytes into the canalicular lumen in the presence of bile salts in an ATP-dependent manner. Promotes biliary phospholipid secretion as canaliculi-containing vesicles from the canalicular plasma membrane. In cooperation with ATP8B1, functions to protect hepatocytes from the deleterious detergent activity of bile salts. Does not confer multidrug resistance (By similarity).

Human Protein Atlas · Open Targets · UniProt

Gene annotation from the Human Protein Atlas and UniProt; see sources & licences.