title: Root avoidance of toxic metals requires the GeBP-LIKE 4 transcription factor in Arabidopsis thaliana.
abstract: Plants reorganize their root architecture to avoid growth into unfavorable regions of the rhizosphere. In a screen based on chimeric repressor gene-silencing technology, we identified the Arabidopsis thaliana GeBP-LIKE 4 (GPL4) transcription factor as an inhibitor of root growth that is induced rapidly in root tips in response to cadmium (Cd). We tested the hypothesis that GPL4 functions in the root avoidance of Cd by analyzing root proliferation in split medium, in which only half of the medium contained toxic concentrations of Cd. The wild-type (WT) plants exhibited root avoidance by inhibiting root growth in the Cd side but increasing root biomass in the control side. By contrast, GPL4-suppression lines exhibited nearly comparable root growth in the Cd and control sides and accumulated more Cd in the shoots than did the WT. GPL4 suppression also altered the root avoidance of toxic concentrations of other essential metals, modulated the expression of many genes related to oxidative stress, and consistently decreased reactive oxygen species concentrations. We suggest that GPL4 inhibits the growth of roots exposed to toxic metals by modulating reactive oxygen species concentrations, thereby allowing roots to colonize noncontaminated regions of the rhizosphere.
authors: Department of Life Science, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Korea.
authors: Deepa
authors: D
authors: Khare
authors: Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan.
authors: Nobukata
authors: N
authors: Mitsuda
authors: School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang, 37673, Korea.
authors: Seungchul
authors: S
authors: Lee
authors: Department of Life Science, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Korea.|Division of Integrative Bioscience and Biotechnology, POSTECH, Pohang, 37673, Korea.
authors: Won-Yong
authors: WY
authors: Song
authors: School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang, 37673, Korea.|Department of New Biology and Center for Plant Aging Research, DGIST, Daegu, 42988, Korea.
authors: Daehee
authors: D
authors: Hwang
authors: Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan.|Division of Strategic Research and Development, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
authors: Masaru
authors: M
authors: Ohme-Takagi
authors: Department of Plant and Microbial Biology, University Zurich, Zollikerstrasse 107, CH-8008, Zürich, Switzerland.
authors: Enrico
authors: E
authors: Martinoia
authors: Department of Life Science, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Korea.|Division of Integrative Bioscience and Biotechnology, POSTECH, Pohang, 37673, Korea.
authors: Youngsook
authors: Y
authors: Lee
authors: Department of Life Science, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Korea.
authors: Jae-Ung
authors: JU
authors: Hwang
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D018533:Biomass; D002452:Cell Count; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D005978:Glutathione / Q000494:pharmacology; D018519:Meristem / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D019216:Metals, Heavy / Q000633:toxicity*; D008954:Models, Biological; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D018520:Plant Shoots / Q000187:drug effects / Q000378:metabolism; D030821:Plants, Genetically Modified; D017382:Reactive Oxygen Species / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D029681:Arabidopsis Proteins; D019216:Metals, Heavy; D017382:Reactive Oxygen Species; D014157:Transcription Factors; D005978:Glutathione
keywords: GLABRA1 ENHANCER BINDING PROTEIN (GeBP) transcription factor; cadmium (Cd); copper (Cu); oxidative stress; reactive oxygen species (ROS); root avoidance; split media assay; zinc (Zn)