title: The DYRK-family kinase Pom1 phosphorylates the F-BAR protein Cdc15 to prevent division at cell poles.
abstract: Division site positioning is critical for both symmetric and asymmetric cell divisions. In many organisms, positive and negative signals cooperate to position the contractile actin ring for cytokinesis. In rod-shaped fission yeast Schizosaccharomyces pombe cells, division at midcell is achieved through positive Mid1/anillin-dependent signaling emanating from the central nucleus and negative signals from the dual-specificity tyrosine phosphorylation-regulated kinase family kinase Pom1 at the cell poles. In this study, we show that Pom1 directly phosphorylates the F-BAR protein Cdc15, a central component of the cytokinetic ring. Pom1-dependent phosphorylation blocks Cdc15 binding to paxillin Pxl1 and C2 domain protein Fic1 and enhances Cdc15 dynamics. This promotes ring sliding from cell poles, which prevents septum assembly at the ends of cells with a displaced nucleus or lacking Mid1. Pom1 also slows down ring constriction. These results indicate that a strong negative signal from the Pom1 kinase at cell poles converts Cdc15 to its closed state, destabilizes the actomyosin ring, and thus promotes medial septation.
authors.affiliation: Department of Fundamental Microbiology, University of Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Pranav
authors.initials: P
authors.lastname: Ullal
authors.affiliation: Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232.
authors.forename: Nathan A
authors.initials: NA
authors.lastname: McDonald
authors.affiliation: Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232.
authors.forename: Jun-Song
authors.initials: JS
authors.lastname: Chen
authors.affiliation: Department of Fundamental Microbiology, University of Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Libera
authors.initials: L
authors.lastname: Lo Presti
authors.affiliation: Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232.
authors.forename: Rachel H
authors.initials: RH
authors.lastname: Roberts-Galbraith
authors.affiliation: Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232.
authors.forename: Kathleen L
authors.initials: KL
authors.lastname: Gould
authors.affiliation: Department of Fundamental Microbiology, University of Lausanne, CH-1015 Lausanne, Switzerland Sophie.Martin@unil.ch.
authors.forename: Sophie G
authors.initials: SG
authors.lastname: Martin
mesh_terms: D000205:Actomyosin / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002455:Cell Division / Q000502:physiology*; D048749:Cytokinesis / Q000502:physiology; D003598:Cytoskeletal Proteins / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D010766:Phosphorylation / Q000502:physiology*; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*; D000097603:Dyrk Kinases
chemical_list: D000205:Actomyosin; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D019204:GTP-Binding Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases; D029702:Schizosaccharomyces pombe Proteins; D000097603:Dyrk Kinases; C082279:CDC15 protein; C535065:Fic1 protein, S pombe; C533048:Pxl1 protein, S pombe; C112212:Pom1 protein, S pombe