title: Arabidopsis LOS5/ABA3 overexpression in transgenic tobacco (Nicotiana tabacum cv. Xanthi-nc) results in enhanced drought tolerance.
abstract: Drought is a major environmental stress factor that affects growth and development of plants. Abscisic acid (ABA), osmotically active compounds, and synthesis of specific proteins, such as proteins that scavenge oxygen radicals, are crucial for plants to adapt to water deficit. LOS5/ABA3 (LOS5) encodes molybdenum-cofactor sulfurase, which is a key regulator of ABA biosynthesis. We overexpressed LOS5 in tobacco using Agrobacterium-mediated transformation. Detached leaves of LOS5-overexpressing seedlings showed lower transpirational water loss than that of nontransgenic seedlings in the same period under normal conditions. When subjected to water-deficit stress, transgenic plants showed less wilting, maintained higher water content and better cellular membrane integrity, accumulated higher quantities of ABA and proline, and exhibited higher activities of antioxidant enzymes, i.e., superoxide dismutase, catalase, peroxidase and ascorbate peroxidase, as compared with control plants. Furthermore, LOS5-overexpressing plants treated with 30% polyethylene glycol showed similar performance in cellular membrane protection, ABA and proline accumulation, and activities of catalase and peroxidase to those under drought stress. Thus, overexpression of LOS5 in transgenic tobacco can enhance drought tolerance.
authors: State Key Laboratory of Plant Physiology and Biochemistry, Department of Agronomy, Centre of Crop Chemical Control, College of Agronomy and Biotechnology, China Agricultural University, No. 2 Yuanmingyuan Xi Lu, Haidian District, Beijing, PR China.
authors: Yuesen
authors: Y
authors: Yue
authors: Mingcai
authors: M
authors: Zhang
authors: Jiachang
authors: J
authors: Zhang
authors: Liusheng
authors: L
authors: Duan
authors: Zhaohu
authors: Z
authors: Li
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000222:Adaptation, Physiological; D000975:Antioxidants / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D055864:Droughts; D004573:Electrolytes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D015227:Lipid Peroxidation / Q000235:genetics; D018515:Plant Leaves / Q000201:enzymology; D018526:Plant Transpiration / Q000502:physiology; D030821:Plants, Genetically Modified; D011392:Proline / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000502:physiology; D013466:Sulfurtransferases / Q000235:genetics / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics* / Q000502:physiology*
chemical_list: D000975:Antioxidants; D029681:Arabidopsis Proteins; D004573:Electrolytes; D013481:Superoxides; D000040:Abscisic Acid; D011392:Proline; C440026:ABA3 protein, Arabidopsis; D013466:Sulfurtransferases