title: Cytokinin Response Factor 6 Represses Cytokinin-Associated Genes during Oxidative Stress.
abstract: Cytokinin is a phytohormone that is well known for its roles in numerous plant growth and developmental processes, yet it has also been linked to abiotic stress response in a less defined manner. Arabidopsis (Arabidopsis thaliana) Cytokinin Response Factor 6 (CRF6) is a cytokinin-responsive AP2/ERF-family transcription factor that, through the cytokinin signaling pathway, plays a key role in the inhibition of dark-induced senescence. CRF6 expression is also induced by oxidative stress, and here we show a novel function for CRF6 in relation to oxidative stress and identify downstream transcriptional targets of CRF6 that are repressed in response to oxidative stress. Analysis of transcriptomic changes in wild-type and crf6 mutant plants treated with H2O2identified CRF6-dependent differentially expressed transcripts, many of which were repressed rather than induced. Moreover, many repressed genes also show decreased expression in 35S:CRF6 overexpressing plants. Together, these findings suggest that CRF6 functions largely as a transcriptional repressor. Interestingly, among the H2O2repressed CRF6-dependent transcripts was a set of five genes associated with cytokinin processes: (signaling) ARR6, ARR9, ARR11, (biosynthesis) LOG7, and (transport) ABCG14. We have examined mutants of these cytokinin-associated target genes to reveal novel connections to oxidative stress. Further examination of CRF6-DNA interactions indicated that CRF6 may regulate its targets both directly and indirectly. Together, this shows that CRF6 functions during oxidative stress as a negative regulator to control this cytokinin-associated module of CRF6-dependent genes and establishes a novel connection between cytokinin and oxidative stress response.
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Paul J
authors.identifier: 0000-0003-3477-9043
authors.initials: PJ
authors.lastname: Zwack
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Inge
authors.identifier: 0000-0001-8125-1239
authors.initials: I
authors.lastname: De Clercq
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Howton
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: H Tucker
authors.initials: HT
authors.lastname: Hallmark
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Andrej
authors.identifier: 0000-0003-3638-1426
authors.initials: A
authors.lastname: Hurny
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Erika A
authors.initials: EA
authors.lastname: Keshishian
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Alyssa M
authors.initials: AM
authors.lastname: Parish
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Eva
authors.initials: E
authors.lastname: Benkova
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: M Shahid
authors.initials: MS
authors.lastname: Mukhtar
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.).
authors.forename: Frank
authors.identifier: 0000-0002-3147-0860
authors.initials: F
authors.lastname: Van Breusegem
authors.affiliation: Department of Biological Sciences, Auburn University, Auburn, AL 36849 (P.J.Z., H.T.H., E.A.K., A.M.P., A.M.R.); Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium (I.D.C., F.V.B.);Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium (I.D.C., F.V.B.);Department of Biology, University of Alabama, Birmingham, AL 35294 (T.C.H., M.S.M.); and Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria (A.H., E.B.) rashotte@auburn.edu.
authors.forename: Aaron M
authors.identifier: 0000-0001-5034-4395
authors.initials: AM
authors.lastname: Rashotte
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002734:Chlorophyll / Q000737:chemistry / Q000378:metabolism; D003583:Cytokinins / Q000378:metabolism*; D005453:Fluorescence; D020869:Gene Expression Profiling / Q000379:methods*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics*; D063990:Gene Ontology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D009154:Mutation; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011485:Protein Binding; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D020798:Two-Hybrid System Techniques
chemical_list: D029681:Arabidopsis Proteins; C585525:CRF6 protein, Arabidopsis; D003583:Cytokinins; D016877:Oxidants; D014157:Transcription Factors; D002734:Chlorophyll; D006861:Hydrogen Peroxide