title: An aquaporin gene from halophyte Sesuvium portulacastrum, SpAQP1, increases salt tolerance in transgenic tobacco.
abstract: SpAQP1 was strongly induced by salt in an ABA-independent way, promoted seed germination and root growth in transgenic tobaccos and increased salt tolerance by increasing the activities of antioxidative enzymes. Aquaporin (AQP) plays crucial roles in the responses of plant to abiotic stresses such as drought, salt and cold. Compared to glycophytes, halophytes often have excellent salt and drought tolerances. To uncover the molecular mechanism of halophyte Sesuvium portulacastrum tolerance to salt, in this study, an AQP gene, SpAQP1, from S. portulacastrum was isolated and characterized. The amino acid sequence of SpAQP1 shared high homology with that of plant plasma membrane intrinsic proteins (PIPs) and contained the distinct molecular features of PIPs. In the phylogenic tree, SpAQP1 was evidently classified as the PIP2 subfamily. SpAQP1 is expressed in roots, stems and leaves, and was significantly induced by NaCl treatment and inhibited by abscisic acid (ABA) treatment. When heterologously expressed in yeast and tobacco, SpAQP1 enhanced the salt tolerance of yeast strains and tobacco plants and promoted seed germination and root growth under salt stress in transgenic plants. The activity of antioxidative enzymes including superoxide dismutase, peroxidase and catalase was increased in transgenic plants overexpressing SpAQP1. Taken together, our studies suggested that SpAQP1 functioned in the responses of S. portulacastrum to salt stress and could increase salt tolerance by enhancing the antioxidative activity of plants.
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Haikou, 571101, People's Republic of China. cularmy@163.com.|Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, 4 Xueyuan Road, Longhua District, Haikou, 571101, People's Republic of China. cularmy@163.com.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Chang
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Haikou, 571101, People's Republic of China.|Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, 4 Xueyuan Road, Longhua District, Haikou, 571101, People's Republic of China.
authors.forename: Xiwen
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Haikou, 571101, People's Republic of China.|Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, 4 Xueyuan Road, Longhua District, Haikou, 571101, People's Republic of China.
authors.forename: Jiahong
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Haikou, 571101, People's Republic of China.|Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, 4 Xueyuan Road, Longhua District, Haikou, 571101, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Fan
authors.affiliation: Hainan Academy of Agricultural Sciences, 4 Xingdan Road, Haikou, 571100, People's Republic of China. zhangzhili@itbb.org.cn.
authors.forename: Zhili
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D035722:Aizoaceae / Q000235:genetics*; D020346:Aquaporins / Q000235:genetics* / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics; D055049:Salt Tolerance / Q000235:genetics*; D055051:Salt-Tolerant Plants / Q000235:genetics*; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism*
chemical_list: D020346:Aquaporins; D010940:Plant Proteins
keywords: Antioxidative enzyme; Aquaporin; Root growth; Salt; Seed germination; Sesuvium portulacastrum