title: Transcription Factor ATAF1 in Arabidopsis Promotes Senescence by Direct Regulation of Key Chloroplast Maintenance and Senescence Transcriptional Cascades.
abstract: Senescence represents a fundamental process of late leaf development. Transcription factors (TFs) play an important role for expression reprogramming during senescence; however, the gene regulatory networks through which they exert their functions, and their physiological integration, are still largely unknown. Here, we identify the Arabidopsis (Arabidopsis thaliana) abscisic acid (ABA)- and hydrogen peroxide-activated TF Arabidopsis thaliana activating factor1 (ATAF1) as a novel upstream regulator of senescence. ATAF1 executes its physiological role by affecting both key chloroplast maintenance and senescence-promoting TFs, namely GOLDEN2-LIKE1 (GLK1) and ORESARA1 (Arabidopsis NAC092), respectively. Notably, while ATAF1 activates ORESARA1, it represses GLK1 expression by directly binding to their promoters, thereby generating a transcriptional output that shifts the physiological balance toward the progression of senescence. We furthermore demonstrate a key role of ATAF1 for ABA- and hydrogen peroxide-induced senescence, in accordance with a direct regulatory effect on ABA homeostasis genes, including nine-CIS-epoxycarotenoid dioxygenase3 involved in ABA biosynthesis and ABC transporter G family member40, encoding an ABA transport protein. Thus, ATAF1 serves as a core transcriptional activator of senescence by coupling stress-related signaling with photosynthesis- and senescence-related transcriptional cascades.
authors.affiliation: University of Potsdam, Institute of Biochemistry and Biology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Plant Signaling Group, Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Commonwealth Scientific and Industrial Research Organization Plant Industry, St. Lucia, Queensland 4067, Australia (G.-P.X.); andDepartament de Biologia Vegetal, Universitat de Barcelona, Facultat de Biologia, 08028 Barcelona, Spain (S.M.-B.).
authors.forename: Prashanth
authors.initials: P
authors.lastname: Garapati
authors.affiliation: University of Potsdam, Institute of Biochemistry and Biology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Plant Signaling Group, Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Commonwealth Scientific and Industrial Research Organization Plant Industry, St. Lucia, Queensland 4067, Australia (G.-P.X.); andDepartament de Biologia Vegetal, Universitat de Barcelona, Facultat de Biologia, 08028 Barcelona, Spain (S.M.-B.).
authors.forename: Gang-Ping
authors.initials: GP
authors.lastname: Xue
authors.affiliation: University of Potsdam, Institute of Biochemistry and Biology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Plant Signaling Group, Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Commonwealth Scientific and Industrial Research Organization Plant Industry, St. Lucia, Queensland 4067, Australia (G.-P.X.); andDepartament de Biologia Vegetal, Universitat de Barcelona, Facultat de Biologia, 08028 Barcelona, Spain (S.M.-B.).
authors.forename: Sergi
authors.identifier: http://orcid.org/0000-0001-6523-6848
authors.initials: S
authors.lastname: Munné-Bosch
authors.affiliation: University of Potsdam, Institute of Biochemistry and Biology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Plant Signaling Group, Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany (P.G., S.B.);Commonwealth Scientific and Industrial Research Organization Plant Industry, St. Lucia, Queensland 4067, Australia (G.-P.X.); andDepartament de Biologia Vegetal, Universitat de Barcelona, Facultat de Biologia, 08028 Barcelona, Spain (S.M.-B.) balazadeh@mpimp-golm.mpg.de.
authors.forename: Salma
authors.identifier: http://orcid.org/0000-0002-5789-4071
authors.initials: S
authors.lastname: Balazadeh
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000235:genetics*; D003624:Darkness; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D006706:Homeostasis / Q000187:drug effects / Q000235:genetics; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008954:Models, Biological; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics
chemical_list: C517610:ATAF1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D012097:Repressor Proteins; D000040:Abscisic Acid; D006861:Hydrogen Peroxide