title: RhoA regulates actin network dynamics during apical surface emergence in multiciliated epithelial cells.
abstract: Homeostatic replacement of epithelial cells from basal precursors is a multistep process involving progenitor cell specification, radial intercalation and, finally, apical surface emergence. Recent data demonstrate that actin-based pushing under the control of the formin protein Fmn1 drives apical emergence in nascent multiciliated epithelial cells (MCCs), but little else is known about this actin network or the control of Fmn1. Here, we explore the role of the small GTPase RhoA in MCC apical emergence. Disruption of RhoA function reduced the rate of apical surface expansion and decreased the final size of the apical domain. Analysis of cell shapes suggests that RhoA alters the balance of forces exerted on the MCC apical surface. Finally, quantitative time-lapse imaging and fluorescence recovery after photobleaching studies argue that RhoA works in concert with Fmn1 to control assembly of the specialized apical actin network in MCCs. These data provide new molecular insights into epithelial apical surface assembly and could also shed light on mechanisms of apical lumen formation.
authors.affiliation: Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Jakub
authors.initials: J
authors.lastname: Sedzinski
authors.affiliation: Cavendish Laboratory, Department of Physics, J.J. Thomson Avenue, University of Cambridge, Cambridge CB3 0HE, UK.|Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
authors.forename: Edouard
authors.initials: E
authors.lastname: Hannezo
authors.affiliation: Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Fan
authors.initials: F
authors.lastname: Tu
authors.affiliation: Centenary Institute of Cancer Medicine and Cell Biology, Locked Bag 6, Newtown, New South Wales 2042, Australia.|Sydney Medical School, The University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: Maté
authors.initials: M
authors.lastname: Biro
authors.affiliation: Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA Wallingford@austin.utexas.edu.
authors.forename: John B
authors.identifier: 0000-0002-6280-8625
authors.initials: JB
authors.lastname: Wallingford
mesh_terms: D051376:Actin-Related Protein 2-3 Complex / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D016764:Cell Polarity; D002923:Cilia / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism*; D005260:Female; D005326:Fetal Proteins / Q000378:metabolism; D000080865:Formins; D006801:Humans; D008840:Microfilament Proteins / Q000378:metabolism; D008954:Models, Biological; D009687:Nuclear Proteins / Q000378:metabolism; D014981:Xenopus; D020742:rhoA GTP-Binding Protein / Q000378:metabolism*
chemical_list: D051376:Actin-Related Protein 2-3 Complex; D000199:Actins; D005326:Fetal Proteins; D000080865:Formins; D008840:Microfilament Proteins; D009687:Nuclear Proteins; D020742:rhoA GTP-Binding Protein
keywords: Actin; Apical emergence; Arp2/3; Fmn1; Multiciliated cells; RhoA