title: TheArabidopsistranscription factor ABIG1 relays ABA signaled growth inhibition and drought induced senescence.
abstract: Drought inhibits plant growth and can also induce premature senescence. Here we identify a transcription factor, ABA INSENSITIVE GROWTH 1 (ABIG1) required for abscisic acid (ABA) mediated growth inhibition, but not for stomatal closure.ABIG1mRNA levels are increased both in response to drought and in response to ABA treatment. When treated with ABA,abig1mutants remain greener and produce more leaves than comparable wild-type plants. When challenged with drought,abig1mutants have fewer yellow, senesced leaves than wild-type. Induction of ABIG1 transcription mimics ABA treatment and regulates a set of genes implicated in stress responses. We propose a model in which drought acts through ABA to increaseABIG1transcription which in turn restricts new shoot growth and promotes leaf senescence. The results have implications for plant breeding: the existence of a mutant that is both ABA resistant and drought resistant points to new strategies for isolating drought resistant genetic varieties.
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, Stanford, United States.
authors.forename: Tie
authors.initials: T
authors.lastname: Liu
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, Stanford, United States.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Longhurst
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, Stanford, United States.
authors.forename: Franklin
authors.initials: F
authors.lastname: Talavera-Rauh
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, Stanford, United States.
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Hokin
authors.affiliation: Department of Plant Biology, Carnegie Institution for Science, Stanford, United States.
authors.forename: M Kathryn
authors.identifier: 0000-0002-5516-1835
authors.initials: MK
authors.lastname: Barton
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D063245:Plant Development; D010937:Plant Growth Regulators / Q000378:metabolism; D013312:Stress, Physiological; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: C000624972:ABIG1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D014157:Transcription Factors; D000040:Abscisic Acid
keywords: A. thaliana; Class II HD-ZIP transcription factors; abscisic acid; developmental biology; drought; leaf development; plant biology; stay green; stem cells; stress