title: A Dual-Function Transcription Factor, AtYY1, Is a Novel Negative Regulator of the Arabidopsis ABA Response Network.
abstract: Abscisic acid (ABA) plays crucial roles in plant growth and development, as well as in response to various environmental stresses. To date, many regulatory genes involved in the ABA response network have been identified; however, their roles have remained to be fully elucidated. In this study, we identified AtYY1, an Arabidopsis homolog of the mammalian C2H2 zinc-finger transcription factor Yin Yang 1 (YY1), as a novel negative regulator of the ABA response. AtYY1 is a dual-function transcription factor with both repression and activation domains. The expression of AtYY1 was induced by ABA and stress conditions including high salt and dehydration. The yy1 mutant was more sensitive to ABA and NaCl than the wild-type, while overexpressing AtYY1 plants were less sensitive. AtYY1 loss also enhanced ABA-induced stomatal closing and drought resistance. Moreover, AtYY1 can bind the ABA REPRESSOR1 (ABR1) promoter and directly upregulate ABR1 expression, as well as negatively regulate ABA- and salt-responsive gene expression. Additional analysis indicated that ABA INSENSITIVE4 (ABI4) might positively regulate AtYY1 expression and that ABR1 can antagonize this regulation. Our findings provide direct evidence that AtYY1 is a novel negative regulator of the ABA response network and that the ABI4-AtYY1-ABR1 regulatory pathway may fine-tune ABA-responsive gene expression in Arabidopsis.
authors.affiliation: Laboratory of Plant Molecular Biology, Centre for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China; Key Laboratory of Crop Gene Resources and Germplasm Enhancement, Ministry of Agriculture, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Li
authors.affiliation: Laboratory of Plant Molecular Biology, Centre for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Xiu-Yun
authors.initials: XY
authors.lastname: Wu
authors.affiliation: Laboratory of Plant Molecular Biology, Centre for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China; Department of Plant Pathology, China Agricultural University, Beijing 100193, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Laboratory of Plant Molecular Biology, Centre for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Song
authors.affiliation: Laboratory of Plant Molecular Biology, Centre for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China. Electronic address: liujy@mail.tsinghua.edu.cn.
authors.forename: Jin-Yuan
authors.initials: JY
authors.lastname: Liu
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D010937:Plant Growth Regulators / Q000494:pharmacology*; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D050986:YY1 Transcription Factor / Q000235:genetics / Q000378:metabolism
chemical_list: C507549:ABR1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D014157:Transcription Factors; D050986:YY1 Transcription Factor; D012965:Sodium Chloride; D000040:Abscisic Acid
keywords: ABA response; ABI4; ABR1; AtYY1; negative regulator