title: L-Met Activates Arabidopsis GLR Ca2+Channels Upstream of ROS Production and Regulates Stomatal Movement.
abstract: Plant glutamate receptor homologs (GLRs) have long been proposed to function as ligand-gated Ca2+channels, but no in planta evidence has been provided. Here, we present genetic evidence that Arabidopsis GLR3.1 and GLR3.5 form Ca2+channels activated by L-methionine (L-Met) at physiological concentrations and regulate stomatal apertures and plant growth. The glr3.1/3.5 mutations resulted in a lower cytosolic Ca2+level, defective Ca2+-induced stomatal closure, and Ca2+-deficient growth disorder, all of which involved L-Met. Patch-clamp analyses of guard cells showed that GLR3.1/3.5 Ca2+channels are activated specifically by L-Met, with the activation abolished in glr3.1/3.5. Moreover, GLR3.1/3.5 Ca2+channels are distinct from previously characterized ROS-activated Ca2+channels and act upstream of ROS, providing Ca2+transients necessary for the activation of NADPH oxidases. Our data indicate that GLR3.1/3.5 constitute L-Met-activated Ca2+channels responsible for maintaining basal [Ca2+]cyt, play a pivotal role in plant growth, and act upstream of ROS, thereby regulating stomatal aperture.
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA; Department of Biology, Duke University, Durham, NC 27708, USA; Department of Chemistry, Capital Normal University, Beijing 100048, China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Kong
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
authors.forename: Heng-Cheng
authors.initials: HC
authors.lastname: Hu
authors.affiliation: Graduate School of Environmental and Life Science, Okayama University, Tsushima-Naka, Okayama 700-8530, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Okuma
authors.affiliation: Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea.
authors.forename: Yuree
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Biological Sciences and Bioengineering Program, Lehigh University, 111 Research Drive, Bethlehem, PA 18015, USA.
authors.forename: Hui Sun
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Graduate School of Environmental and Life Science, Okayama University, Tsushima-Naka, Okayama 700-8530, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Munemasa
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
authors.forename: Daeshik
authors.initials: D
authors.lastname: Cho
authors.affiliation: College of Life Sciences, Capital Normal University, Beijing 100048, China.
authors.forename: Chuanli
authors.initials: C
authors.lastname: Ju
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
authors.forename: Leah
authors.initials: L
authors.lastname: Pedoeim
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
authors.forename: Barbara
authors.initials: B
authors.lastname: Rodriguez
authors.affiliation: College of Life Sciences, Capital Normal University, Beijing 100048, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Biological Sciences and Bioengineering Program, Lehigh University, 111 Research Drive, Bethlehem, PA 18015, USA.
authors.forename: Wonpil
authors.initials: W
authors.lastname: Im
authors.affiliation: Graduate School of Environmental and Life Science, Okayama University, Tsushima-Naka, Okayama 700-8530, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Murata
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: Zhen-Ming
authors.initials: ZM
authors.lastname: Pei
authors.affiliation: Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea; Department of New Biology, DGIST, Daegu 42988, Republic of Korea. Electronic address: jkwak@dgist.ac.kr.
authors.forename: June M
authors.initials: JM
authors.lastname: Kwak
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D008715:Methionine / Q000378:metabolism*; D009154:Mutation; D019255:NADPH Oxidases / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D017470:Receptors, Glutamate / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D017382:Reactive Oxygen Species; D017470:Receptors, Glutamate; C000601589:glutamate receptor 3.5, Arabidopsis; D009569:Nitric Oxide; D008715:Methionine; D019255:NADPH Oxidases; D002118:Calcium
keywords: Ca(2+) channel; Ca(2+) deficiency; L-methionine; glutamate receptor homologs; guard cell; reactive oxygen species; stomatal movement