title: The AAA-type ATPase AtSKD1 contributes to vacuolar maintenance of Arabidopsis thaliana.
abstract: The vacuole is the most prominent organelle of plant cells. Despite its importance for many physiological and developmental aspects of plant life, little is known about its biogenesis and maintenance. Here we show that Arabidopsis plants expressing a dominant-negative version of the AAA (ATPase associated with various cellular activities) ATPase AtSKD1 (SUPPRESSOR OF K+ TRANSPORT GROWTH DEFECT1) under the control of the trichome-specific GLABRA2 (GL2) promoter exhibit normal vacuolar development in early stages of trichome development. Shortly after its formation, however, the large central vacuole is fragmented and finally disappears completely. Secretion assays with amylase fused to the vacuolar sorting signal of Sporamin show that dominant-negative AtSKD1 inhibits vacuolar trafficking of the reporter that is instead secreted. In addition, trichomes expressing dominant-negative AtSKD1 frequently contain multiple nuclei. Our results suggest that AtSKD1 contributes to vacuolar protein trafficking and thereby to the maintenance of the large central vacuole of plant cells, and might play a role in cell-cycle regulation.
authors.affiliation: Biozentrum Köln, University of Cologne, Zülpicher Street 47 b, 50674 Cologne, Germany.
authors.forename: Mojgan
authors.initials: M
authors.lastname: Shahriari
authors.forename: Channa
authors.initials: C
authors.lastname: Keshavaiah
authors.forename: David
authors.initials: D
authors.lastname: Scheuring
authors.forename: Aneta
authors.initials: A
authors.lastname: Sabovljevic
authors.forename: Peter
authors.initials: P
authors.lastname: Pimpl
authors.forename: Rainer E
authors.initials: RE
authors.lastname: Häusler
authors.forename: Martin
authors.initials: M
authors.lastname: Hülskamp
authors.forename: Swen
authors.initials: S
authors.lastname: Schellmann
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics; D011992:Endosomes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic; D014617:Vacuoles / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D018744:DNA, Plant; D000251:Adenosine Triphosphatases