title: Molecular networks linked by Moesin drive remodeling of the cell cortex during mitosis.
abstract: The cortical mechanisms that drive the series of mitotic cell shape transformations remain elusive. In this paper, we identify two novel networks that collectively control the dynamic reorganization of the mitotic cortex. We demonstrate that Moesin, an actin/membrane linker, integrates these two networks to synergize the cortical forces that drive mitotic cell shape transformations. We find that the Pp1-87B phosphatase restricts high Moesin activity to early mitosis and down-regulates Moesin at the polar cortex, after anaphase onset. Overactivation of Moesin at the polar cortex impairs cell elongation and thus cytokinesis, whereas a transient recruitment of Moesin is required to retract polar blebs that allow cortical relaxation and dissipation of intracellular pressure. This fine balance of Moesin activity is further adjusted by Skittles and Pten, two enzymes that locally produce phosphoinositol 4,5-bisphosphate and thereby, regulate Moesin cortical association. These complementary pathways provide a spatiotemporal framework to explain how the cell cortex is remodeled throughout cell division.
authors.affiliation: Cell Biology of Mitosis laboratory, Université de Montréal, Montréal, Québec H3C 3J7, Canada.
authors.forename: Chantal
authors.initials: C
authors.lastname: Roubinet
authors.forename: Barbara
authors.initials: B
authors.lastname: Decelle
authors.forename: Gaëtan
authors.initials: G
authors.lastname: Chicanne
authors.forename: Jonas F
authors.initials: JF
authors.lastname: Dorn
authors.forename: Bernard
authors.initials: B
authors.lastname: Payrastre
authors.forename: François
authors.initials: F
authors.lastname: Payre
authors.forename: Sébastien
authors.initials: S
authors.lastname: Carreno
mesh_terms: D000705:Anaphase / Q000502:physiology*; D000818:Animals; D002460:Cell Line; D048430:Cell Shape / Q000502:physiology*; D048749:Cytokinesis / Q000502:physiology*; D015536:Down-Regulation / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051059:PTEN Phosphohydrolase / Q000235:genetics / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000235:genetics / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000235:genetics
chemical_list: D029721:Drosophila Proteins; D008565:Membrane Proteins; D019269:Phosphatidylinositol 4,5-Diphosphate; C099886:moesin, Drosophila; D010749:Phosphoprotein Phosphatases; D051059:PTEN Phosphohydrolase; C487101:PTEN protein, Drosophila