Up Close with Membrane Lipid-Protein Complexes

NPI-Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, CA 90024-1759, USA.
Science (Impact Factor: 33.61). 10/2011; 334(6054):320-1. DOI: 10.1126/science.1214084
Source: PubMed


Cells, and the organelles within them, are surrounded by lipid-bilayer membranes that compartmentalize biochemical reactions
and pathways. Membrane-embedded proteins control the flux of molecules, energy, and information such that the segregated compartments
function as a unified living cell. Traditionally, membrane proteins were pictured as floating around quite independently of
the surrounding lipids, yet when this fluid-mosaic model was described, Singer and Nicolson qualified that “a small fraction
of the lipid may interact specifically with the membrane proteins” (1). It has taken 40 years to fully appreciate the importance of this assertion. On page 380 of this issue, Zhou et al. (2) report mass spectrometry of intact integral membrane protein complexes solubilized from bilayers. The results show that
specific structural lipids remain bound in the gas phase and can be counted.

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    • "Biological membranes are highly organized proteolipid domains and there is increasing evidence of fine-scale organization into microdomains (Whitelegge, 2011; Holthuis and Ungermann, 2013). These comprise localized assemblies of specific proteins and lipids and are important in the spatial and temporal control of membrane protein complex assembly and regulation. "
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