title: Identification of Open Stomata1-Interacting Proteins Reveals Interactions with Sucrose Non-fermenting1-Related Protein Kinases2 and with Type 2A Protein Phosphatases That Function in Abscisic Acid Responses.
abstract: The plant hormone abscisic acid (ABA) controls growth and development and regulates plant water status through an established signaling pathway. In the presence of ABA, pyrabactin resistance/regulatory component of ABA receptor proteins inhibit type 2C protein phosphatases (PP2Cs). This, in turn, enables the activation of Sucrose Nonfermenting1-Related Protein Kinases2 (SnRK2). Open Stomata1 (OST1)/SnRK2.6/SRK2E is a major SnRK2-type protein kinase responsible for mediating ABA responses. Arabidopsis (Arabidopsis thaliana) expressing an epitope-tagged OST1 in the recessive ost1-3 mutant background was used for the copurification and identification of OST1-interacting proteins after osmotic stress and ABA treatments. These analyses, which were confirmed using bimolecular fluorescence complementation and coimmunoprecipitation, unexpectedly revealed homo- and heteromerization of OST1 with SnRK2.2, SnRK2.3, OST1, and SnRK2.8. Furthermore, several OST1-complexed proteins were identified as type 2A protein phosphatase (PP2A) subunits and as proteins involved in lipid and galactolipid metabolism. More detailed analyses suggested an interaction network between ABA-activated SnRK2-type protein kinases and several PP2A-type protein phosphatase regulatory subunits. pp2a double mutants exhibited a reduced sensitivity to ABA during seed germination and stomatal closure and an enhanced ABA sensitivity in root growth regulation. These analyses add PP2A-type protein phosphatases as another class of protein phosphatases to the interaction network of SnRK2-type protein kinases.
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Rainer
authors.initials: R
authors.lastname: Waadt
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Bianca
authors.initials: B
authors.lastname: Manalansan
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Navin
authors.identifier: http://orcid.org/0000-0002-5297-7097
authors.initials: N
authors.lastname: Rauniyar
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Shintaro
authors.initials: S
authors.lastname: Munemasa
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Booker
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Benjamin
authors.initials: B
authors.lastname: Brandt
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Christian
authors.initials: C
authors.lastname: Waadt
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Dmitri A
authors.identifier: http://orcid.org/0000-0002-0497-1723
authors.initials: DA
authors.lastname: Nusinow
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Steve A
authors.initials: SA
authors.lastname: Kay
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Hans-Henning
authors.identifier: http://orcid.org/0000-0001-8000-0817
authors.initials: HH
authors.lastname: Kunz
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Karin
authors.initials: K
authors.lastname: Schumacher
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: Alison
authors.initials: A
authors.lastname: DeLong
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.).
authors.forename: John R
authors.identifier: http://orcid.org/0000-0001-5267-1672
authors.initials: JR
authors.lastname: Yates
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116 (R.W., B.M., S.M., B.B., H.-H.K., J.I.S.);Centre for Organismal Studies, Plant Developmental Biology, University of Heidelberg, 69120 Heidelberg, Germany (R.W., K.S.);Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037 (N.R., J.R.Y.);Division of Agricultural and Life Science, Graduate School of Environmental and Life Science, Okayama University, Okayama 7008530, Japan (S.M.);Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912 (M.A.B., A.D.);Department of Biology, Donald Danforth Plant Science Center, St. Louis, Missouri 63132 (D.A.N.); andMolecular and Computational Biology Section, University of Southern California, Los Angeles, California 90089 (S.A.K.) jischroeder@ucsd.edu.
authors.forename: Julian I
authors.initials: JI
authors.lastname: Schroeder
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D005453:Fluorescence; D018525:Germination / Q000187:drug effects; D047468:Immunoprecipitation; D009154:Mutation / Q000235:genetics; D030821:Plants, Genetically Modified; D011485:Protein Binding / Q000187:drug effects; D060066:Protein Interaction Maps / Q000187:drug effects; D011494:Protein Kinases / Q000378:metabolism*; D055503:Protein Multimerization / Q000187:drug effects; D054648:Protein Phosphatase 2 / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D021122:Protein Subunits / Q000378:metabolism; D015203:Reproducibility of Results; D020798:Two-Hybrid System Techniques
chemical_list: D029681:Arabidopsis Proteins; D021122:Protein Subunits; C492978:SnRK2 protein, Arabidopsis; D000040:Abscisic Acid; D011494:Protein Kinases; C472139:OST1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; D054648:Protein Phosphatase 2