title: ABO3, a WRKY transcription factor, mediates plant responses to abscisic acid and drought tolerance in Arabidopsis.
abstract: The biological functions of WRKY transcription factors in plants have been widely studied, but their roles in abiotic stress are still not well understood. We isolated an ABA overly sensitive mutant, abo3, which is disrupted by a T-DNA insertion in At1g66600 encoding a WRKY transcription factor AtWRKY63. The mutant was hypersensitive to ABA in both seedling establishment and seedling growth. However, stomatal closure was less sensitive to ABA, and the abo3 mutant was less drought tolerant than the wild type. Northern blot analysis indicated that the expression of the ABA-responsive transcription factor ABF2/AREB1 was markedly lower in the abo3 mutant than in the wild type. The abo3 mutation also reduced the expression of stress-inducible genes RD29A and COR47, especially early during ABA treatment. ABO3 is able to bind the W-box in the promoter of ABF2in vitro. These results uncover an important role for a WRKY transcription factor in plant responses to ABA and drought stress.
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, ChinaDepartment of Botany and Plant Sciences, Institute for Integrative Genome Biology, 2150 Batchelor Hall, University of California, Riverside, CA 92521, USAChina Agricultural University, University of California-Riverside Center for Biological Sciences and Biotechnology, Beijing 100193, ChinaNational Center for Plant Gene Research, Beijing 100193, China.
authors.forename: Xiaozhi
authors.initials: X
authors.lastname: Ren
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Chen
authors.forename: Yue
authors.initials: Y
authors.lastname: Liu
authors.forename: Hairong
authors.initials: H
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.forename: Xuhui
authors.initials: X
authors.lastname: Hong
authors.forename: Jian-Kang
authors.initials: JK
authors.lastname: Zhu
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Gong
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D015152:Blotting, Northern; D055864:Droughts; D017343:Genes, Plant; D009154:Mutation; D054046:Plant Stomata / Q000502:physiology; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins