The distribution of phospholipids across the plasma membrane of eukaryotic cells is generated and maintained through the action of several transmembrane transporters.  ATP-dependent �flippases� and �floppases� move lipids in the inward or outward direction, respectively, while a �scramblase� has been associated with the bidirectional energy-independent movement of lipids across the membrane.  Red blood cells possess a limited set of these lipid transporters and the focus of our studies is to identify and characterize these proteins, especially with regard to substrate specificity.  The erythrocyte flippase belongs to a subclass of P-type ATPases and is structurally and stereochemically selective for phosphatidylserine.  Red cell floppases belong to the ABC transporter superfamily and transport a variety of lipids.  Scramblase activity is activated by Ca2+ and is non-specific for its lipid substrates.  Our studies have also revealed that flippase and scramblase activities might be related; flippase activity-inhibiting antibodies also inhibit scramblase activity in intact cells.

Flippases, floppases, and scramblases: Transporters that regulate transbilayer phospholipid asymmetry in the eukaryotic plasma membrane

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.