ATP-dependent translocase ABCB1 (P-gp)

ATP-dependent translocase ABCB1, commonly known as P-glycoprotein (P-gp), is a membrane-associated protein that functions as an ATP-dependent efflux pump with broad substrate specificity. It plays a critical role in the transport of various molecules across extra- and intra-cellular membranes, particularly contributing to multidrug resistance by actively extruding xenobiotic compounds and drugs from cells. Its primary function is to efflux xenobiotic compounds with broad substrate specificity out of cells. This activity is central to its role in multidrug resistance—by pumping anticancer drugs out of tumor cells—and also contributes to drug disposition at physiological barriers like the blood-brain barrier.

Other names

P-glycoprotein 1Multidrug resistance protein 1MDR1ATP-binding cassette sub-family B member 1Phospholipid transporter ABCB1PGY1CD243

ATP-dependent efflux of substrates from cells, including drugs and phospholipids. Substrate enters P-gp either from within the inner leaflet or cytoplasmic side. Upon binding of both substrate and ATP at cytoplasmic sites, hydrolysis shifts the substrate for excretion out of the cell. The process resets after ADP release.