The Role of ENHANCED RESPONSES TO ABA1 (ERA1) in Arabidopsis Stomatal Responses Is Beyond ABA Signaling.
Proper stomatal responses are essential for plant function in an altered environment. The core signaling pathway for abscisic acid (ABA)-induced stomatal closure involves perception of the hormone that leads to the activation of guard cell anion channels by the protein kinase OPEN STOMATA1. Several other regulators are suggested to modulate the ABA signaling pathway, including the protein ENHANCED RESPONSE TO ABA1 (ERA1), that encodes the farnesyl transferase β-subunit. Theera1mutant is hypersensitive to ABA during seed germination and shows a more closed stomata phenotype. Using a genetics approach with the double mutantsera1 abi1-1andera1 ost1, we show that whileera1suppressed the high stomatal conductance ofabi1-1andost1, the ERA1 function was not required for stomatal closure in response to ABA and environmental factors. Further experiments indicated a role for ERA1 in blue light-induced stomatal opening. In addition, we show that ERA1 function in disease resistance was independent of its role in stomatal regulation. Our results indicate a function for ERA1 in stomatal opening and pathogen immunity.
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Pirko
P
Jalakas
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Yi-Chun
http://orcid.org/0000-0002-7487-4443
YC
Huang
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Yu-Hung
http://orcid.org/0000-0002-5520-3206
YH
Yeh
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Laurent
L
Zimmerli
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Ebe
E
Merilo
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Hannes
http://orcid.org/0000-0002-6895-3583
H
Kollist
Institute of Technology, University of Tartu, 50411 Tartu, Estonia (P.J., E.M., H.K., M.B.); Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan (Y.-C.H., Y.-H.Y., L.Z.); and Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland (M.B.).
Mikael
http://orcid.org/0000-0002-1135-2496
M
Brosché
D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D008027:Light; D009154:Mutation; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D054046:Plant Stomata / Q000502:physiology*; D044224:Pseudomonas syringae / Q000472:pathogenicity; D015398:Signal Transduction; D015293:Transducin / Q000235:genetics / Q000378:metabolism
C000611520:ASG2 protein, Arabidopsis; D029681:Arabidopsis Proteins; C411293:ERA1 protein, Arabidopsis; D000040:Abscisic Acid; D003577:Cytochrome P-450 Enzyme System; C474079:brassinosteroid-6 oxidase 2, Arabidopsis; D015293:Transducin