title: COP1 jointly modulates cytoskeletal processes and electrophysiological responses required for stomatal closure.
abstract: Reorganization of the cortical microtubule cytoskeleton is critical for guard cell function. Here, we investigate how environmental and hormonal signals cause these rearrangements and find that COP1, a RING-finger-type ubiquitin E3 ligase, is required for degradation of tubulin, likely by the 26S proteasome. This degradation is required for stomatal closing. In addition to regulating the cytoskeleton, we show that cop1 mutation impaired the activity of S-type anion channels, which are critical for stomatal closure. Thus, COP1 is revealed as a potential coordinator of cytoskeletal and electrophysiological activities required for guard cell function.
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA.
authors.forename: Rajnish
authors.initials: R
authors.lastname: Khanna
authors.affiliation: Division of Biological Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA; Present address: College of Forest Resources and Environment, Nanjing Forestry University, Nanjing, 210037, China.
authors.forename: Junlin
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA.
authors.forename: Tong-Seung
authors.initials: TS
authors.lastname: Tseng
authors.affiliation: Division of Biological Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
authors.forename: Julian I
authors.initials: JI
authors.lastname: Schroeder
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA.
authors.forename: David W
authors.initials: DW
authors.lastname: Ehrhardt
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA. Electronic address: briggs@stanford.edu.
authors.forename: Winslow R
authors.initials: WR
authors.lastname: Briggs
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D055724:Electrophysiological Phenomena / Q000187:drug effects; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism*; D057054:Molecular Imaging; D009154:Mutation; D054046:Plant Stomata / Q000033:anatomy & histology* / Q000187:drug effects; D059748:Proteolysis / Q000187:drug effects; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D000040:Abscisic Acid; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases; D002118:Calcium
keywords: hormone signaling.; microtubule dynamics; stomatal function