title: Srv2/CAP is required for polarized actin cable assembly and patch internalization during clathrin-mediated endocytosis.
abstract: The dynamic assembly and disassembly of actin filaments is essential for the formation and transport of vesicles during endocytosis. In yeast, two types of actin structures, namely cortical patches and cytoplasmic cables, play a direct role in endocytosis, but how their interaction is regulated remains unclear. Here, we show that Srv2/CAP, an evolutionarily conserved actin regulator, is required for efficient endocytosis owing to its role in the formation of the actin patches that aid initial vesicle invagination and of the actin cables that these move along. Deletion of the SRV2 gene resulted in the appearance of aberrant fragmented actin cables that frequently moved past actin patches, the sites of endocytosis. We find that the C-terminal CARP domain of Srv2p is vitally important for the proper assembly of actin patches and cables; we also demonstrate that the N-terminal helical folded domain of Srv2 is required for its localization to actin patches, specifically to the ADP-actin rich region through an interaction with cofilin. These results demonstrate the in vivo roles of Srv2p in the regulation of the actin cytoskeleton during clathrin-mediated endocytosis.
authors.affiliation: Department of Liberal Arts, Tokyo University of Technology, 5-23-22 Nishikamada, Ota-ku, Tokyo 144-8535, Japan Research Center for RNA Science, RIST, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Junko Y
authors.initials: JY
authors.lastname: Toshima
authors.affiliation: Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Chika
authors.initials: C
authors.lastname: Horikomi
authors.affiliation: Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Asuka
authors.initials: A
authors.lastname: Okada
authors.affiliation: Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Makiko N
authors.initials: MN
authors.lastname: Hatori
authors.affiliation: Research Center for RNA Science, RIST, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Nagano
authors.affiliation: Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Masuda
authors.affiliation: Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Yamamoto
authors.affiliation: Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg A-3400, Austria.
authors.forename: Daria Elisabeth
authors.initials: DE
authors.lastname: Siekhaus
authors.affiliation: Research Center for RNA Science, RIST, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijyuku, Katsushika-ku, Tokyo 125-8585, Japan jtosiscb@rs.noda.tus.ac.jp.
authors.forename: Jiro
authors.initials: J
authors.lastname: Toshima
mesh_terms: D051339:Actin Depolymerizing Factors / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D048868:Adaptor Proteins, Signal Transducing / Q000502:physiology*; D021961:Cell Membrane Structures / Q000378:metabolism; D022163:Clathrin-Coated Vesicles / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000502:physiology*; D004705:Endocytosis; D008840:Microfilament Proteins / Q000378:metabolism; D000072417:Protein Domains; D055503:Protein Multimerization; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000378:metabolism / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism / Q000502:physiology*
chemical_list: C062612:ABP1 protein, S cerevisiae; D051339:Actin Depolymerizing Factors; D000199:Actins; D048868:Adaptor Proteins, Signal Transducing; D003598:Cytoskeletal Proteins; D008840:Microfilament Proteins; C073751:SRV2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins
keywords: Actin; CAP; Cofilin; Endocytosis; Srv2