Spatio-temporal remodeling of functional membrane microdomains organizes the signaling networks of a bacterium.

TitleSpatio-temporal remodeling of functional membrane microdomains organizes the signaling networks of a bacterium.
Publication TypeJournal Article
Year of Publication2015
AuthorsSchneider, J, Klein, T, Mielich-Süss, B, Koch, G, Franke, C, Kuipers, OP, Kovács, ÁT, Sauer, M, Lopez, D
JournalPLoS Genet
Volume11
Issue4
Paginatione1005140
Date Published2015 Apr
ISSN1553-7404
Abstract

Lipid rafts are membrane microdomains specialized in the regulation of numerous cellular processes related to membrane organization, as diverse as signal transduction, protein sorting, membrane trafficking or pathogen invasion. It has been proposed that this functional diversity would require a heterogeneous population of raft domains with varying compositions. However, a mechanism for such diversification is not known. We recently discovered that bacterial membranes organize their signal transduction pathways in functional membrane microdomains (FMMs) that are structurally and functionally similar to the eukaryotic lipid rafts. In this report, we took advantage of the tractability of the prokaryotic model Bacillus subtilis to provide evidence for the coexistence of two distinct families of FMMs in bacterial membranes, displaying a distinctive distribution of proteins specialized in different biological processes. One family of microdomains harbors the scaffolding flotillin protein FloA that selectively tethers proteins specialized in regulating cell envelope turnover and primary metabolism. A second population of microdomains containing the two scaffolding flotillins, FloA and FloT, arises exclusively at later stages of cell growth and specializes in adaptation of cells to stationary phase. Importantly, the diversification of membrane microdomains does not occur arbitrarily. We discovered that bacterial cells control the spatio-temporal remodeling of microdomains by restricting the activation of FloT expression to stationary phase. This regulation ensures a sequential assembly of functionally specialized membrane microdomains to strategically organize signaling networks at the right time during the lifespan of a bacterium.

DOI10.1371/journal.pgen.1005140
Alternate JournalPLoS Genet.