[Membrane proteins and phospholipids as effectors of reverse cholesterol transport]

Abstract

The review highlights the membrane aspect of cholesterol efflux from cell membranes to high density lipoproteins (HDL), an initial stage of reverse cholesterol transport to liver. Special attention is paid to ABC-A1 transporter and membrane SR-B1 receptor, their properties, putative mechanisms of action and their role in reverse cholesterol transport. Interaction of ABC-AI with plasma free apoA1 is suggested to facilitate the efflux of membrane phospholipids and formation of their complex with apoAI. Then this complex accepts the membrane cholesterol, with lipidation till the full HDL particle is formed. For a number of cells the correlation of cholesterol efflux into HDL with SR-BI expression was shown. The reversible binding of receptor SR-BI with HDL is supposed to influence molecular organization of membrane lipids, that promotes the efflux of cholesterol molecules out of the membrane.