Arabidopsis synaptotagmin 1 is required for the maintenance of plasma membrane integrity and cell viability.
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.
Schapire
Arnaldo L
AL
Departamento de Biología Molecular y Bioquímica, Universidad de Málaga, 29071 Málaga, Spain.
Voigt
Boris
B
Jasik
Jan
J
Rosado
Abel
A
Lopez-Cobollo
Rosa
R
Menzel
Diedrik
D
Salinas
Julio
J
Mancuso
Stefano
S
Valpuesta
Victoriano
V
Baluska
Frantisek
F
Botella
Miguel A
MA
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
D029681:Arabidopsis Proteins; D012965:Sodium Chloride; D050863:Synaptotagmin I; C000606467:At2g20990 protein, Arabidopsis