title: Overexpression of the wheat aquaporin gene, TaAQP7, enhances drought tolerance in transgenic tobacco.
abstract: Aquaporin (AQP) proteins have been shown to transport water and other small molecules through biological membranes, which is crucial for plants to combat stress caused by drought. However, the precise role of AQPs in drought stress response is not completely understood in plants. In this study, a PIP2 subgroup gene AQP, designated as TaAQP7, was cloned and characterized from wheat. Expression of TaAQP7-GFP fusion protein revealed its localization in the plasma membrane. TaAQP7 exhibited high water channel activity in Xenopus laevis oocytes and TaAQP7 transcript was induced by dehydration, and treatments with polyethylene glycol (PEG), abscisic acid (ABA) and H(2)O(2). Further, TaAQP7 was upregulated after PEG treatment and was blocked by inhibitors of ABA biosynthesis, implying that ABA signaling was involved in the upregulation of TaAQP7 after PEG treatment. Overexpression of TaAQP7 increased drought tolerance in tobacco. The transgenic tobacco lines had lower levels of malondialdehyde (MDA) and H(2)O(2), and less ion leakage (IL), but higher relative water content (RWC) and superoxide dismutase (SOD) and catalase (CAT) activities when compared with the wild type (WT) under drought stress. Taken together, our results show that TaAQP7 confers drought stress tolerance in transgenic tobacco by increasing the ability to retain water, reduce ROS accumulation and membrane damage, and enhance the activities of antioxidants.
authors.affiliation: Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan, China.
authors.forename: Shiyi
authors.initials: S
authors.lastname: Zhou
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Deng
authors.forename: Zhanbing
authors.initials: Z
authors.lastname: Ma
authors.forename: Lihong
authors.initials: L
authors.lastname: Chen
authors.forename: Chao
authors.initials: C
authors.lastname: Huang
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Yanzhen
authors.initials: Y
authors.lastname: He
authors.forename: Guangxiao
authors.initials: G
authors.lastname: Yang
authors.forename: Guangyuan
authors.initials: G
authors.lastname: He
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics*; D000818:Animals; D020346:Aquaporins / Q000235:genetics* / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D003681:Dehydration; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008315:Malondialdehyde / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D009997:Osmotic Pressure / Q000187:drug effects; D010539:Permeability / Q000187:drug effects; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011092:Polyethylene Glycols / Q000494:pharmacology; D036226:Seedlings / Q000187:drug effects / Q000235:genetics; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D013482:Superoxide Dismutase / Q000378:metabolism; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics* / Q000502:physiology*; D014908:Triticum / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D014867:Water / Q000378:metabolism; D014982:Xenopus laevis
chemical_list: D020346:Aquaporins; D010940:Plant Proteins; D014867:Water; D011092:Polyethylene Glycols; D008315:Malondialdehyde; D000040:Abscisic Acid; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase