Auxin regulates SNARE-dependent vacuolar morphology restricting cell size.
The control of cellular growth is central to multicellular patterning. In plants, the encapsulating cell wall literally binds neighbouring cells to each other and limits cellular sliding/migration. In contrast to its developmental importance, growth regulation is poorly understood in plants. Here, we reveal that the phytohormone auxin impacts on the shape of the biggest plant organelle, the vacuole. TIR1/AFBs-dependent auxin signalling posttranslationally controls the protein abundance of vacuolar SNARE components. Genetic and pharmacological interference with the auxin effect on vacuolar SNAREs interrelates with auxin-resistant vacuolar morphogenesis and cell size regulation. Vacuolar SNARE VTI11 is strictly required for auxin-reliant vacuolar morphogenesis and loss of function renders cells largely insensitive to auxin-dependent growth inhibition. Our data suggests that the adaptation of SNARE-dependent vacuolar morphogenesis allows auxin to limit cellular expansion, contributing to root organ growth rates.
Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria.
Christian
C
Löfke
Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria.
Kai
K
Dünser
Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria.
David
D
Scheuring
Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria.
Jürgen
J
Kleine-Vehn
D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D048429:Cell Size / Q000187:drug effects; D044783:F-Box Proteins / Q000235:genetics / Q000378:metabolism; D015151:Immunoblotting; D007210:Indoleacetic Acids / Q000378:metabolism* / Q000494:pharmacology; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology; D030821:Plants, Genetically Modified; D050766:Qb-SNARE Proteins / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D050600:SNARE Proteins / Q000235:genetics / Q000378:metabolism*; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism*
D029681:Arabidopsis Proteins; D044783:F-Box Proteins; D007210:Indoleacetic Acids; D008164:Luminescent Proteins; D010937:Plant Growth Regulators; D050766:Qb-SNARE Proteins; D011956:Receptors, Cell Surface; D050600:SNARE Proteins; C501405:TIR1 protein, Arabidopsis; C120751:vesicle transport v-SNARE 11 protein, Arabidopsis
arabidopsis; auxin; cell biology; cell size; growth; plant biology; vacuole