title: AtrbohD and AtrbohF positively regulate abscisic acid-inhibited primary root growth by affecting Ca2+ signalling and auxin response of roots in Arabidopsis.
abstract: Reactive oxygen species (ROS) originating from the NADPH oxidases AtrbohD and AtrbohF play an important role in abscisic acid (ABA)-inhibited primary root growth in Arabidopsis. However, the mechanisms underlying this process remain elusive. In this study, the double mutant atrbohD1/F1 and atrbohD2/F2, in which both AtrbohD and AtrbohF were disrupted, were less sensitive to ABA suppression of root cell elongation than wild-type (WT) plants. Furthermore, the double mutants showed impaired ABA responses in roots, including ROS generation, cytosolic Ca(2+) increases, and activation of plasma membrane Ca(2+)-permeable channels compared with WT. Exogenous H2O2 can activate the Ca(2+) currents in roots of atrbohD1/F1. In addition, exogenous application of the auxin transport inhibitor naphthylphthalamic acid effectively promoted ABA inhibition of root growth of the mutants relative to that of WT. The ABA-induced decreases in auxin sensitivity of the root tips were more pronounced in WT than in atrbohD1/F1. These findings suggest that both AtrbohD and AtrbohF are essential for ABA-promoted ROS production in roots. ROS activate Ca(2+) signalling and reduce auxin sensitivity of roots, thus positively regulating ABA-inhibited primary root growth in Arabidopsis.
authors: State Key Laboratory of Cotton Biology, Henan Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng 475004, Henan, China.
authors: Yiheng
authors: Y
authors: Jiao
authors: Lirong
authors: L
authors: Sun
authors: Yalin
authors: Y
authors: Song
authors: Limin
authors: L
authors: Wang
authors: Liping
authors: L
authors: Liu
authors: Liyue
authors: L
authors: Zhang
authors: Bo
authors: B
authors: Liu
authors: Ning
authors: N
authors: Li
authors: Chen
authors: C
authors: Miao
authors: Fushun
authors: F
authors: Hao
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D000331:Aequorin / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects*; D002452:Cell Count; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D007210:Indoleacetic Acids / Q000494:pharmacology*; D018519:Meristem / Q000187:drug effects / Q000254:growth & development; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D019255:NADPH Oxidases / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000040:Abscisic Acid; D000331:Aequorin; D029681:Arabidopsis Proteins; D002118:Calcium; D015220:Calcium Channels; D006861:Hydrogen Peroxide; D007210:Indoleacetic Acids; D019255:NADPH Oxidases; C568857:AT5G47910 protein, Arabidopsis; C000589475:RBOH F protein, Arabidopsis
keywords: Abscisic acid; Arabidopsis; NADPH oxidase; auxin; calcium; primary root elongation.