title: A stable microtubule array drives fission yeast polarity reestablishment upon quiescence exit.
abstract: Cells perpetually face the decision to proliferate or to stay quiescent. Here we show that upon quiescence establishment, Schizosaccharomyces pombe cells drastically rearrange both their actin and microtubule (MT) cytoskeletons and lose their polarity. Indeed, while polarity markers are lost from cell extremities, actin patches and cables are reorganized into actin bodies, which are stable actin filament-containing structures. Astonishingly, MTs are also stabilized and rearranged into a novel antiparallel bundle associated with the spindle pole body, named Q-MT bundle. We have identified proteins involved in this process and propose a molecular model for Q-MT bundle formation. Finally and importantly, we reveal that Q-MT bundle elongation is involved in polarity reestablishment upon quiescence exit and thereby the efficient return to the proliferative state. Our work demonstrates that quiescent S. pombe cells assemble specific cytoskeleton structures that improve the swiftness of the transition back to proliferation.
authors.affiliation: Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, 33000 Bordeaux, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, 33077 Bordeaux, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Laporte
authors.affiliation: Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, 33000 Bordeaux, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, 33077 Bordeaux, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Courtout
authors.affiliation: Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, 33000 Bordeaux, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, 33077 Bordeaux, France.
authors.forename: Benoît
authors.initials: B
authors.lastname: Pinson
authors.affiliation: Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, 33000 Bordeaux, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, 33077 Bordeaux, France.
authors.forename: Jim
authors.initials: J
authors.lastname: Dompierre
authors.affiliation: Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, 33000 Bordeaux, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, 33077 Bordeaux, France.
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Salin
authors.affiliation: Bordeaux Imaging Center, Pôle d'imagerie du végétal, Institut National de la Recherche Agronomique, 33140 Villenave d'Ornon, France.
authors.forename: Lysiane
authors.initials: L
authors.lastname: Brocard
authors.affiliation: Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, 33000 Bordeaux, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, 33077 Bordeaux, France isabelle.sagot@ibgc.cnrs.fr.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Sagot
mesh_terms: D016764:Cell Polarity; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism*; D055550:Protein Stability; D021381:Protein Transport; D012568:Schizosaccharomyces / Q000166:cytology / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism; D064048:Spindle Pole Bodies / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism
chemical_list: C510980:Atb2 protein, S pombe; D008869:Microtubule-Associated Proteins; D029702:Schizosaccharomyces pombe Proteins; D014404:Tubulin; C505279:mto2p protein, S pombe