Multidrug resistance protein 1 is not associated to detergent-resistant membranes

Abstract

Multidrug resistance protein 1 (MRP1) is a member of the ATP-binding cassette superfamily. Using the energy provided by ATP hydrolysis, it transports a broad spectrum of substrates across the plasma membrane, including hormones, leukotriene C 4 , bile salts, and anti-cancer drugs.Recent works have suggested that P-glycoprotein is associated to cholesterol and sphingolipid-rich membrane microdomains and that cholesterol upregulates its ATPase and drug transport activities. Confocal microscopy experiments and Triton X-100 extraction of detergent-resistant membranes provide evidence that MRP1 is not located in raft-like structures and that its activity is downregulated by cholesterol. The data are discussed in terms of cholesterol-protein interaction and topology.

Bile salt-stimulated phospholipid efflux mediated by ABCB4 localized in nonraft membranes

“…In this model, vesiculation may be induced by enriched in rafts ( 27,35 ). It has been shown that ABCA1 and ABCC1 are not associated with membrane raft domains ( 39,40,50,51 ), while ABCG2 is located in membrane rafts ( 44 ). Although ABCB1 has been reported to exist in rafts and nonraft membrane domains, depending on the cell type, experimental conditions, and methods, it is generally accepted that ABCB1 is marginally associated with TXI membranes ( 26 ).…”

Multidrug resistance protein 1 localization in lipid raft domains and prostasomes in prostate cancer cell lines

“… 6 , 18 – 20 In the case of MRP1, there are some controversies about the presence of this transporter in lipid rafts. 21 – 23 …”