title: Activation of Mitochondrial Protein Phosphatase SLP2 by MIA40 Regulates Seed Germination.
abstract: Reversible protein phosphorylation catalyzed by protein kinases and phosphatases represents the most prolific and well-characterized posttranslational modification known. Here, we demonstrate that Arabidopsis (Arabidopsis thaliana) Shewanella-like protein phosphatase 2 (AtSLP2) is a bona fide Ser/Thr protein phosphatase that is targeted to the mitochondrial intermembrane space (IMS) where it interacts with the mitochondrial oxidoreductase import and assembly protein 40 (AtMIA40), forming a protein complex. Interaction with AtMIA40 is necessary for the phosphatase activity of AtSLP2 and is dependent on the formation of disulfide bridges on AtSLP2. Furthermore, by utilizing atslp2 null mutant, AtSLP2 complemented and AtSLP2 overexpressing plants, we identify a function for the AtSLP2-AtMIA40 complex in negatively regulating gibberellic acid-related processes during seed germination. Results presented here characterize a mitochondrial IMS-localized protein phosphatase identified in photosynthetic eukaryotes as well as a protein phosphatase target of the highly conserved eukaryotic MIA40 IMS oxidoreductase.
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.); moorhead@ucalgary.ca.|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and moorhead@ucalgary.ca.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.) moorhead@ucalgary.ca.
authors.forename: R Glen
authors.identifier: 0000-0003-2773-4381
authors.initials: RG
authors.lastname: Uhrig
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Anne-Marie
authors.identifier: 0000-0002-0593-4166
authors.initials: AM
authors.lastname: Labandera
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Lay-Yin
authors.initials: LY
authors.lastname: Tang
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Nicolas A
authors.identifier: 0000-0002-7981-7827
authors.initials: NA
authors.lastname: Sieben
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Marilyn
authors.initials: M
authors.lastname: Goudreault
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Edward
authors.initials: E
authors.lastname: Yeung
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Anne-Claude
authors.initials: AC
authors.lastname: Gingras
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.).|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.).
authors.forename: Marcus A
authors.initials: MA
authors.lastname: Samuel
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada (R.G.U., A.-M.L.,L.-Y.T., N.A.S., E.Y., M.A.S., G.B.G.M.); moorhead@ucalgary.ca.|Group of Plant Biotechnology, Department of Biology, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland (R.G.U.); and moorhead@ucalgary.ca.|Samuel Lunenfeld Research Institute at Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada (M.G., A.-C.G.) moorhead@ucalgary.ca.
authors.forename: Greg B G
authors.identifier: 0000-0003-3282-7590
authors.initials: GB
authors.lastname: Moorhead
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000187:drug effects / Q000196:embryology* / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism*; D053898:Biosynthetic Pathways / Q000187:drug effects; D004220:Disulfides / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D018525:Germination / Q000187:drug effects; D005875:Gibberellins / Q000096:biosynthesis; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology*; D051336:Mitochondrial Membranes / Q000187:drug effects / Q000378:metabolism; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000378:metabolism*; D008954:Models, Biological; D010084:Oxidation-Reduction / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D012639:Seeds / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism*; D016415:Sequence Alignment; D013379:Substrate Specificity / Q000187:drug effects; D014230:Triazoles / Q000494:pharmacology
chemical_list: D029681:Arabidopsis Proteins; D004220:Disulfides; D005875:Gibberellins; C555648:Mia40 protein, Arabidopsis; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D024101:Mitochondrial Proteins; C000592614:SLP2 protein, Arabidopsis; D014230:Triazoles; D000040:Abscisic Acid; C007842:gibberellic acid; C092705:uniconazole