title: In vivo visualization of F-actin structures during the development of the moss Physcomitrella patens.
abstract: * The 'in planta' visualization of F-actin in all cells and in all developmental stages of a plant is a challenging problem. By using the soybean heat inducible Gmhsp17.3B promoter instead of a constitutive promoter, we have been able to label all cells in various developmental stages of the moss Physcomitrella patens, through a precise temperature tuning of the expression of green fluorescent protein (GFP)-talin. * A short moderate heat treatment was sufficient to induce proper labeling of the actin cytoskeleton and to allow the visualization of time-dependent organization of F-actin structures without impairment of cell viability. * In growing moss cells, dense converging arrays of F-actin structures were present at the growing tips of protonema cell, and at the localization of branching. Protonema and leaf cells contained a network of thick actin cables; during de-differentiation of leaf cells into new protonema filaments, the thick bundled actin network disappeared, and a new highly polarized F-actin network formed. * The controlled expression of GFP-talin through an inducible promoter improves significantly the 'in planta' imaging of actin.
authors.affiliation: SV/IBI, EPFL, Station 15, CH-1015 Lausanne, Switzerland.
authors.forename: Andrija
authors.initials: A
authors.lastname: Finka
authors.affiliation: Station de Génétique et d'Amélioration des Plantes, INRA, Route de St Cyr, F-78026 Versailles, France.
authors.forename: Didier G
authors.initials: DG
authors.lastname: Schaefer
authors.affiliation: Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Younousse
authors.initials: Y
authors.lastname: Saidi
authors.affiliation: Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Pierre
authors.initials: P
authors.lastname: Goloubinoff
authors.affiliation: Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Zrÿd
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000737:chemistry / Q000502:physiology*; D019068:Bryopsida / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000235:genetics; D013025:Glycine max / Q000235:genetics; D016608:Talin / Q000235:genetics
chemical_list: D000199:Actins; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D016608:Talin; D049452:Green Fluorescent Proteins