title: Phosphorylation of PACSIN2 by protein kinase C triggers the removal of caveolae from the plasma membrane.
abstract: PACSIN2, a membrane-sculpting BAR domain protein, localizes to caveolae. Here, we found that protein kinase C (PKC) phosphorylates PACSIN2 at serine 313, thereby decreasing its membrane binding and tubulation capacities. Concomitantly, phosphorylation decreased the time span for which caveolae could be tracked at the plasma membrane (the 'tracking duration'). Analyses of the phospho-mimetic S313E mutant suggested that PACSIN2 phosphorylation was sufficient to reduce caveolar-tracking durations. Both hypotonic treatment and isotonic drug-induced PKC activation increased PACSIN2 phosphorylation at serine 313 and shortened caveolar-tracking durations. Caveolar-tracking durations were also reduced upon the expression of other membrane-binding-deficient PACSIN2 mutants or upon RNA interference (RNAi)-mediated PACSIN2 depletion, pointing to a role for PACSIN2 levels in modulating the lifetime of caveolae. Interestingly, the decrease in membrane-bound PACSIN2 was inversely correlated with the recruitment and activity of dynamin 2, a GTPase that mediates membrane scission. Furthermore, expression of EHD2, which stabilizes caveolae and binds to PACSIN2, restored the tracking durations of cells with reduced PACSIN2 levels. These findings suggest that the PACSIN2 phosphorylation decreases its membrane-binding activity, thereby decreasing its stabilizing effect on caveolae and triggering dynamin-mediated removal of caveolae.
authors.affiliation: Laboratory of Membrane and Cytoskeleton Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Senju
authors.affiliation: Crystallography, Max Delbrück Center for Molecular Medicine, Berlin 13125, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Rosenbaum
authors.affiliation: Crystallography, Max Delbrück Center for Molecular Medicine, Berlin 13125, Germany.
authors.forename: Claudio
authors.initials: C
authors.lastname: Shah
authors.affiliation: Laboratory of Membrane and Cytoskeleton Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Hamada-Nakahara
authors.affiliation: Laboratory of Membrane and Cytoskeleton Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Itoh
authors.affiliation: Laboratory of System Physiology, Department of Biomedical Engineering, Graduate School of Medicine, University of Tokyo, Tokyo 113-0033, Japan.
authors.forename: Kimiko
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Laboratory of Membrane and Cytoskeleton Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan Laboratory of Molecular Medicine and Cell Biology, Graduate School of Biosciences, Nara Institute of Science and Technology, Ikoma 630-0192, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Hanawa-Suetsugu
authors.affiliation: Crystallography, Max Delbrück Center for Molecular Medicine, Berlin 13125, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Daumke
authors.affiliation: Laboratory of Membrane and Cytoskeleton Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan Laboratory of Molecular Medicine and Cell Biology, Graduate School of Biosciences, Nara Institute of Science and Technology, Ikoma 630-0192, Japan suetsugu@bs.naist.jp.
authors.forename: Shiro
authors.initials: S
authors.lastname: Suetsugu
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000096:biosynthesis*; D021941:Caveolae / Q000378:metabolism*; D051242:Caveolin 1 / Q000378:metabolism; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism*; D034285:Dynamin II; D034281:Dynamins / Q000378:metabolism; D042783:Endothelial Cells / Q000502:physiology; D006367:HeLa Cells; D006801:Humans; D010766:Phosphorylation; D011485:Protein Binding; D051571:Protein Kinase C-alpha / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering; D015398:Signal Transduction
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D051242:Caveolin 1; C406446:EHD2 protein, human; C120714:PACSIN2 protein, human; D034741:RNA, Small Interfering; C496628:PRKCA protein, human; D051571:Protein Kinase C-alpha; C000593490:DNM2 protein, human; D034285:Dynamin II; D034281:Dynamins
keywords: BAR domain; Caveolae; Mechanical stress; Phosphorylation; Protein kinase C