title: Two Chloroplast Proteins Suppress Drought Resistance by Affecting ROS Production in Guard Cells.
abstract: Chloroplast as the site for photosynthesis is an essential organelle in plants, but little is known about its role in stomatal regulation and drought resistance. In this study, we show that two chloroplastic proteins essential for thylakoid formation negatively regulate drought resistance in Arabidopsis (Arabidopsis thaliana). By screening a mutant pool with T-DNA insertions in nuclear genes encoding chloroplastic proteins, we identified an HCF106 knockdown mutant exhibiting increased resistance to drought stress. The hcf106 mutant displayed elevated levels of reactive oxygen species (ROS) in guard cells, improved stomatal closure, and reduced water loss under drought conditions. The HCF106 protein was found to physically interact with THF1, a previously identified chloroplastic protein crucial for thylakoid formation. The thf1 mutant phenotypically resembled the hcf106 mutant and displayed more ROS accumulation in guard cells, increased stomatal closure, reduced water loss, and drought resistant phenotypes compared to the wild type. The hcf106thf1 double mutant behaved similarly as the thf1 single mutant. These results suggest that HCF106 and THF1 form a complex to modulate chloroplast function and that the complex is important for ROS production in guard cells and stomatal control in response to environmental stresses. Our results also suggest that modulating chloroplastic proteins could be a way for improving drought resistance in crops.
authors.affiliation: Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences (Z.W., F.W., Y.H., J.-K.Z.), University of Chinese Academy of Sciences (Z.W., F.W., Y.H.), Chinese Academy of Sciences, Shanghai 200032, China.|National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China (J.H.).|Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (H.S.); and.|Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (J.-K.Z.).
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences (Z.W., F.W., Y.H., J.-K.Z.), University of Chinese Academy of Sciences (Z.W., F.W., Y.H.), Chinese Academy of Sciences, Shanghai 200032, China.|National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China (J.H.).|Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (H.S.); and.|Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (J.-K.Z.).
authors.forename: Fuxing
authors.initials: F
authors.lastname: Wang
authors.affiliation: Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences (Z.W., F.W., Y.H., J.-K.Z.), University of Chinese Academy of Sciences (Z.W., F.W., Y.H.), Chinese Academy of Sciences, Shanghai 200032, China.|National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China (J.H.).|Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (H.S.); and.|Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (J.-K.Z.).
authors.forename: Yechun
authors.initials: Y
authors.lastname: Hong
authors.affiliation: Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences (Z.W., F.W., Y.H., J.-K.Z.), University of Chinese Academy of Sciences (Z.W., F.W., Y.H.), Chinese Academy of Sciences, Shanghai 200032, China.|National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China (J.H.).|Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (H.S.); and.|Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (J.-K.Z.).
authors.forename: Jirong
authors.initials: J
authors.lastname: Huang
authors.affiliation: Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences (Z.W., F.W., Y.H., J.-K.Z.), University of Chinese Academy of Sciences (Z.W., F.W., Y.H.), Chinese Academy of Sciences, Shanghai 200032, China; huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.|National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China (J.H.); huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.|Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (H.S.); and huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.|Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (J.-K.Z.) huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.
authors.forename: Huazhong
authors.identifier: 0000-0003-3817-9774
authors.initials: H
authors.lastname: Shi
authors.affiliation: Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences (Z.W., F.W., Y.H., J.-K.Z.), University of Chinese Academy of Sciences (Z.W., F.W., Y.H.), Chinese Academy of Sciences, Shanghai 200032, China; huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.|National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China (J.H.); huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.|Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (H.S.); and huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.|Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (J.-K.Z.) huazhong.shi@ttu.edu jkzhu@sibs.ac.cn.
authors.forename: Jian-Kang
authors.identifier: 0000-0001-5134-731X
authors.initials: JK
authors.lastname: Zhu
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D060365:Chloroplast Proteins / Q000378:metabolism*; D055864:Droughts; D004843:Epistasis, Genetic; D018506:Gene Expression Regulation, Plant; D055785:Gene Knockdown Techniques; D005816:Genetic Complementation Test; D006861:Hydrogen Peroxide / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity / Q000235:genetics; D010641:Phenotype; D054046:Plant Stomata / Q000166:cytology* / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011485:Protein Binding; D016601:RNA-Binding Proteins / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D060365:Chloroplast Proteins; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; D017382:Reactive Oxygen Species; C512069:THF1 protein, Arabidopsis; C000622971:Tric1 protein, Arabidopsis; D006861:Hydrogen Peroxide