title: With or without rafts? Alternative views on cell membranes.
abstract: The fundamental mechanisms of protein and lipid organization at the plasma membrane have continued to engage researchers for decades. Among proposed models, one idea has been particularly successful which assumes that sterol-dependent nanoscopic phases of different lipid chain order compartmentalize proteins, thereby modulating protein functionality. This model of membrane rafts has sustainably sparked the fields of membrane biophysics and biology, and shifted membrane lipids into the spotlight of research; by now, rafts have become an integral part of our terminology to describe a variety of cell biological processes. But is the evidence clear enough to continue supporting a theoretical concept which has resisted direct proof by observation for nearly twenty years? In this essay, we revisit findings that gave rise to and substantiated the raft hypothesis, discuss its impact on recent studies, and present alternative mechanisms to account for plasma membrane heterogeneity.
authors.affiliation: Institute of Applied Physics, Vienna University of Technology, Vienna, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Sevcsik
authors.affiliation: Institute of Applied Physics, Vienna University of Technology, Vienna, Austria.
authors.forename: Gerhard J
authors.initials: GJ
authors.lastname: Schütz
mesh_terms: D002462:Cell Membrane / Q000378:metabolism* / Q000502:physiology*; D008563:Membrane Lipids / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism
chemical_list: D008563:Membrane Lipids; D008565:Membrane Proteins
keywords: lipids; membrane heterogeneity; membrane proteins; membrane rafts; phase separation; plasma membrane; raft hypothesis