Article

Lipid Rafts As a Membrane-Organizing Principle

Max Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany.
Science (Impact Factor: 33.61). 01/2010; 327(5961):46-50. DOI: 10.1126/science.1174621
Source: PubMed

ABSTRACT

Cell membranes display a tremendous complexity of lipids and proteins designed to perform the functions cells require. To
coordinate these functions, the membrane is able to laterally segregate its constituents. This capability is based on dynamic
liquid-liquid immiscibility and underlies the raft concept of membrane subcompartmentalization. Lipid rafts are fluctuating
nanoscale assemblies of sphingolipid, cholesterol, and proteins that can be stabilized to coalesce, forming platforms that
function in membrane signaling and trafficking. Here we review the evidence for how this principle combines the potential
for sphingolipid-cholesterol self-assembly with protein specificity to selectively focus membrane bioactivity.

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    • "Cholesterol partitions into liquid-ordered/disordered phases to roughly the same extent, and this changes the properties of the lipid phases [31]. Other cell membrane lipids, such as sphingolipids, are also important in the formation of ordered membrane lipid domains [32]. Sphingomyelins and phosphatidylcholines constitute more than one-half of the plasma membrane phospholipids and form the main partners for cholesterol in some specialized lipid domains [33]. "

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