title: K252a-sensitive protein kinases but not okadaic acid-sensitive protein phosphatases regulate methyl jasmonate-induced cytosolic Ca2+ oscillation in guard cells of Arabidopsis thaliana.
abstract: Methyl jasmonate (MeJA) induces stomatal closure similar to abscisic acid (ABA), and MeJA signaling in guard cells shares some signal components with ABA signaling. As part of this process, MeJA as well as ABA induce the elevation and oscillation of cytosolic free-calcium concentrations ([Ca(2+)](cyt)) in guard cells. While abscisic acid-induced [Ca(2+)](cyt) oscillation has been extensively studied, MeJA-induced [Ca(2+)](cyt) oscillation is less well understood. In this study, we investigated the effects of K252a (a broad-range protein kinase inhibitor) and okadaic acid (OA, a protein phosphatase 1 and 2A inhibitor) on MeJA-induced [Ca(2+)](cyt) oscillation in guard cells of Arabidopsis thaliana ecotype Columbia expressing the Ca(2+) reporter yellow cameleon 3.6. The protein kinase inhibitor K252a abolished MeJA-induced stomatal closure and reduced MeJA-elicited [Ca(2+)](cyt) oscillation. The protein phosphatase inhibitor OA, on the other hand, did not inhibit these processes. These results suggest that MeJA signaling involves activation of K252a-sensitive protein kinases upstream of [Ca(2+)](cyt) oscillation but not activation of an OA-sensitive protein phosphatase in guard cells of A. thaliana ecotype Columbia.
authors.affiliation: Graduate School of Natural Science and Technology, Okayama University, 1-1-1 Tsushima-Naka, Okayama 700-8530, Japan.
authors.forename: Mohammad Anowar
authors.initials: MA
authors.lastname: Hossain
authors.forename: Shintaro
authors.initials: S
authors.lastname: Munemasa
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Izumi C
authors.initials: IC
authors.lastname: Mori
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Murata
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000085:Acetates / Q000494:pharmacology*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000187:drug effects / Q000378:metabolism; D002118:Calcium / Q000494:pharmacology*; D020013:Calcium Signaling / Q000187:drug effects*; D002227:Carbazoles / Q000494:pharmacology; D003517:Cyclopentanes / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D026121:Indole Alkaloids / Q000494:pharmacology; D019319:Okadaic Acid / Q000494:pharmacology; D054883:Oxylipins / Q000494:pharmacology*; D010749:Phosphoprotein Phosphatases / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology; D011494:Protein Kinases / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors
chemical_list: D000085:Acetates; D029681:Arabidopsis Proteins; D002227:Carbazoles; D003517:Cyclopentanes; D004791:Enzyme Inhibitors; D026121:Indole Alkaloids; D054883:Oxylipins; D019319:Okadaic Acid; D000040:Abscisic Acid; C072239:methyl jasmonate; C049985:staurosporine aglycone; D011494:Protein Kinases; C067024:okadaic acid-sensitive phosphatase; D010749:Phosphoprotein Phosphatases; D002118:Calcium