title: Arabidopsis synaptotagmin 1 is required for the maintenance of plasma membrane integrity and cell viability.
abstract: Plasma membrane repair in animal cells uses synaptotagmin 7, a Ca(2+)-activated membrane fusion protein that mediates delivery of intracellular membranes to wound sites by a mechanism resembling neuronal Ca(2+)-regulated exocytosis. Here, we show that loss of function of the homologous Arabidopsis thaliana Synaptotagmin 1 protein (SYT1) reduces the viability of cells as a consequence of a decrease in the integrity of the plasma membrane. This reduced integrity is enhanced in the syt1-2 null mutant in conditions of osmotic stress likely caused by a defective plasma membrane repair. Consistent with a role in plasma membrane repair, SYT1 is ubiquitously expressed, is located at the plasma membrane, and shares all domains characteristic of animal synaptotagmins (i.e., an N terminus-transmembrane domain and a cytoplasmic region containing two C2 domains with phospholipid binding activities). Our analyses support that membrane trafficking mediated by SYT1 is important for plasma membrane integrity and plant fitness.
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Universidad de Málaga, 29071 Málaga, Spain.
authors.forename: Arnaldo L
authors.initials: AL
authors.lastname: Schapire
authors.forename: Boris
authors.initials: B
authors.lastname: Voigt
authors.forename: Jan
authors.initials: J
authors.lastname: Jasik
authors.forename: Abel
authors.initials: A
authors.lastname: Rosado
authors.forename: Rosa
authors.initials: R
authors.lastname: Lopez-Cobollo
authors.forename: Diedrik
authors.initials: D
authors.lastname: Menzel
authors.forename: Julio
authors.initials: J
authors.lastname: Salinas
authors.forename: Stefano
authors.initials: S
authors.lastname: Mancuso
authors.forename: Victoriano
authors.initials: V
authors.lastname: Valpuesta
authors.forename: Frantisek
authors.initials: F
authors.lastname: Baluska
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Botella
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015153:Blotting, Western; D002462:Cell Membrane / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D002470:Cell Survival / Q000187:drug effects* / Q000235:genetics; D005816:Genetic Complementation Test; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D009995:Osmosis; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012965:Sodium Chloride / Q000494:pharmacology; D050863:Synaptotagmin I / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014026:Nicotiana / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D012965:Sodium Chloride; D050863:Synaptotagmin I; C000606467:At2g20990 protein, Arabidopsis