title: Functional competition within a membrane: Lipid recognition vs. transmembrane helix oligomerization.
abstract: Binding of specific lipids to large, polytopic membrane proteins is well described, and it is clear that such lipids are crucial for protein stability and activity. In contrast, binding of defined lipid species to individual transmembrane helices and regulation of transmembrane helix monomer-oligomer equilibria by binding of distinct lipids is a concept, which has emerged only lately. Lipids bind to single-span membrane proteins, both in the juxta-membrane region as well as in the hydrophobic membrane core. While some interactions counteract transmembrane helix oligomerization, in other cases lipid binding appears to enhance oligomerization. As reversible oligomerization is involved in activation of many membrane proteins, binding of defined lipids to single-span transmembrane proteins might be a mechanism to regulate and/or fine-tune the protein activity. But how could lipid binding trigger the activity of a protein? How can binding of a single lipid molecule to a transmembrane helix affect the structure of a transmembrane helix oligomer, and consequently its signaling state? These questions are discussed in the present article based on recent results obtained with simple, single-span transmembrane proteins. This article is part of a Special Issue entitled: Lipid-protein interactions.
authors: Department of Pharmacy and Biochemistry, Johannes-Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 30, 55128 Mainz, Germany.
authors: Michael
authors: M
authors: Stangl
authors: Department of Pharmacy and Biochemistry, Johannes-Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 30, 55128 Mainz, Germany. Electronic address: Dirk.Schneider@uni-mainz.de.
authors: Dirk
authors: D
authors: Schneider
mesh_terms: D001667:Binding, Competitive; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism; D008563:Membrane Lipids / Q000737:chemistry* / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D015394:Molecular Structure; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary
chemical_list: D008051:Lipid Bilayers; D008563:Membrane Lipids; D008565:Membrane Proteins
keywords: C99; Lipid binding; Membrane protein; Oligomerization; Syntaxin 1A; p24