Premium
Stimulus Dependent Redistribution of Membrane Raft Cholesterol in Human Platelets
Author(s) -
BoeszeBattaglia Kathleen,
Schimmel Richard J.,
Gretzula Cheryl
Publication year - 2004
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.200550107
Subject(s) - lipid raft , membrane , raft , biophysics , microbiology and biotechnology , cell membrane , intracellular , sphingomyelin , cholesterol , membrane fluidity , lipid bilayer , chemistry , extracellular , biology , biochemistry , organic chemistry , copolymer , polymer
Cell membranes provide a requisite dynamic interface to facilitate communication between the extracellular environment and the intracellular milieu. These membranes contain proteins that span and/or are loosely associated with the lipid bilayer. The organization of lipids and proteins components into membrane micro‐domains provides a temporal and spatial signaling platform for communication. Recently, cholesterol and sphingomyelin enriched membrane micro‐domains known as lipid rafts have been implicated in cell signaling events. In these studies we have advanced our hypothesis that stimulus dependent rearrangement of cholesterol into and out of membrane rafts provides a unique lipid–mediated regulatory mechanism. Using fluorescent derivatives of cholesterol, we have shown that membrane raft associated cholesterol was altered in response to collagen‐induced platelet aggregatory stimulation. Collagen stimulation resulted in a rapid redistribution of cholesterol from the outer to the inner membrane monolayer. The reorganization of the outer membrane monolayer resulted in a concomitant increase in outer monolayer fluidity. These studies are the first to show that membrane cholesterol was released from the exchangeable membrane raft pool in response to physiological stimuli.