title: Ca2+ induces clustering of membrane proteins in the plasma membrane via electrostatic interactions.
abstract: Membrane proteins and membrane lipids are frequently organized in submicron-sized domains within cellular membranes. Factors thought to be responsible for domain formation include lipid-lipid interactions, lipid-protein interactions and protein-protein interactions. However, it is unclear whether the domain structure is regulated by other factors such as divalent cations. Here, we have examined in native plasma membranes and intact cells the role of the second messenger Ca(2+) in membrane protein organization. We find that Ca(2+) at low micromolar concentrations directly redistributes a structurally diverse array of membrane proteins via electrostatic effects. Redistribution results in a more clustered pattern, can be rapid and triggered by Ca(2+) influx through voltage-gated calcium channels and is reversible. In summary, the data demonstrate that the second messenger Ca(2+) strongly influences the organization of membrane proteins, thus adding a novel and unexpected factor that may control the domain structure of biological membranes.
authors.affiliation: Department of Neurobiology, Max-Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Felipe E
authors.initials: FE
authors.lastname: Zilly
authors.forename: Nagaraj D
authors.initials: ND
authors.lastname: Halemani
authors.forename: David
authors.initials: D
authors.lastname: Walrafen
authors.forename: Luis
authors.initials: L
authors.lastname: Spitta
authors.forename: Arne
authors.initials: A
authors.lastname: Schreiber
authors.forename: Reinhard
authors.initials: R
authors.lastname: Jahn
authors.forename: Thorsten
authors.initials: T
authors.lastname: Lang
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002413:Cations, Divalent / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D051381:Rats; D055672:Static Electricity
chemical_list: D002413:Cations, Divalent; D008565:Membrane Proteins; D002118:Calcium