title: An adhesome comprising laminin, dystroglycan and myosin IIA is required during notochord development in Xenopus laevis.
abstract: Dystroglycan (Dg) is a transmembrane receptor for laminin that must be expressed at the right time and place in order to be involved in notochord morphogenesis. The function of Dg was examined in Xenopus laevis embryos by knockdown of Dg and overexpression and replacement of the endogenous Dg with a mutated form of the protein. This analysis revealed that Dg is required for correct laminin assembly, for cell polarization during mediolateral intercalation and for proper differentiation of vacuoles. Using mutations in the cytoplasmic domain, we identified two sites that are involved in cell polarization and are required for mediolateral cell intercalation, and a site that is required for vacuolation. Furthermore, using a proteomic analysis, the cytoskeletal non-muscle myosin IIA has been identified for the first time as a molecular link between the Dg-cytoplasmic domain and cortical actin. The data allowed us to identify the adhesome laminin-Dg-myosin IIA as being required to maintain the cortical actin cytoskeleton network during vacuolation, which is crucial to maintain the shape of notochordal cells.
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7622, Laboratoire de Biologie du Développement, 75252 Paris, Cedex 05, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Buisson
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7009, Observatoire Océanographique, Villefranche-sur-mer 06230, France.
authors.forename: Cathy
authors.initials: C
authors.lastname: Sirour
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7622, Laboratoire de Biologie du Développement, 75252 Paris, Cedex 05, France.
authors.forename: Nicole
authors.initials: N
authors.lastname: Moreau
authors.affiliation: Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, Bergen N-5008, Norway.
authors.forename: Elsa
authors.initials: E
authors.lastname: Denker
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7622, Laboratoire de Biologie du Développement, 75252 Paris, Cedex 05, France.
authors.forename: Ronan
authors.initials: R
authors.lastname: Le Bouffant
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7622, Laboratoire de Biologie du Développement, 75252 Paris, Cedex 05, France.
authors.forename: Aline
authors.initials: A
authors.lastname: Goullancourt
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7622, Laboratoire de Biologie du Développement, 75252 Paris, Cedex 05, France thierry.darribere@upmc.fr valerie.bello@snv.jussieu.fr.
authors.forename: Thierry
authors.initials: T
authors.lastname: Darribère
authors.affiliation: Sorbonne Universités, UPMC Univ. Paris 06, UMR CNRS 7622, Laboratoire de Biologie du Développement, 75252 Paris, Cedex 05, France thierry.darribere@upmc.fr valerie.bello@snv.jussieu.fr.
authors.forename: Valérie
authors.initials: V
authors.lastname: Bello
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001973:Bromodeoxyuridine; D016764:Cell Polarity / Q000502:physiology; D049030:Dystroglycans / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D047468:Immunoprecipitation; D017403:In Situ Hybridization; D007797:Laminin / Q000378:metabolism*; D060172:Morpholinos / Q000235:genetics; D024507:Nonmuscle Myosin Type IIA / Q000378:metabolism*; D009672:Notochord / Q000196:embryology*; D038081:Organogenesis / Q000502:physiology*; D040901:Proteomics; D053719:Tandem Mass Spectrometry; D014617:Vacuoles / Q000502:physiology*; D014982:Xenopus laevis / Q000196:embryology*
chemical_list: D007797:Laminin; D060172:Morpholinos; D049030:Dystroglycans; D024507:Nonmuscle Myosin Type IIA; D001973:Bromodeoxyuridine
keywords: Actin; Cell polarity; Dystroglycan; Extracellular matrix; Myosin IIA; Notochord; Xenopus laevis