title: A Functional Antagonistic Relationship between Auxin and Mitochondrial Retrograde Signaling Regulates Alternative Oxidase1a Expression in Arabidopsis.
abstract: The perception and integration of stress stimuli with that of mitochondrion function are important during periods of perturbed cellular homeostasis. In a continuous effort to delineate these mitochondrial/stress-interacting networks, forward genetic screens using the mitochondrial stress response marker alternative oxidase 1a (AOX1a) provide a useful molecular tool to identify and characterize regulators of mitochondrial stress signaling (referred to as regulators of alternative oxidase 1a [RAOs] components). In this study, we reveal that mutations in genes coding for proteins associated with auxin transport and distribution resulted in a greater induction of AOX1a in terms of magnitude and longevity. Three independent mutants for polarized auxin transport, rao3/big, rao4/pin-formed1, and rao5/multidrug-resistance1/abcb19, as well as the Myb transcription factor rao6/asymmetric leaves1 (that displays altered auxin patterns) were identified and resulted in an acute sensitivity toward mitochondrial dysfunction. Induction of the AOX1a reporter system could be inhibited by the application of auxin analogs or reciprocally potentiated by blocking auxin transport. Promoter activation studies with AOX1a::GUS and DR5::GUS lines further confirmed a clear antagonistic relationship between the spatial distribution of mitochondrial stress and auxin response kinetics, respectively. Genome-wide transcriptome analyses revealed that mitochondrial stress stimuli, such as antimycin A, caused a transient suppression of auxin signaling and conversely, that auxin treatment repressed a part of the response to antimycin A treatment, including AOX1a induction. We conclude that mitochondrial stress signaling and auxin signaling are reciprocally regulated, balancing growth and stress response(s).
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Aneta
authors.initials: A
authors.lastname: Ivanova
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Simon R
authors.initials: SR
authors.lastname: Law
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Reena
authors.initials: R
authors.lastname: Narsai
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Owen
authors.initials: O
authors.lastname: Duncan
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Botao
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Olivier
authors.initials: O
authors.lastname: Van Aken
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Jordan D
authors.initials: JD
authors.lastname: Radomiljac
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: Margaretha
authors.initials: M
authors.lastname: van der Merwe
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.).
authors.forename: KeKe
authors.initials: K
authors.lastname: Yi
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, Department of Botany, School of Life Science, La Trobe University, Bundoora, Victoria 3086, Australia (A.I., S.R.L., O.D., B.Z., J.D.R., J.W.);Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia (A.I., R.N., J.-H.L., O.V.A., J.D.R., M.v.d.M.); andState Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (K.Y.) j.whelan@latrobe.edu.au.
authors.forename: James
authors.initials: J
authors.lastname: Whelan