title: Overexpression of SmLEA enhances salt and drought tolerance in Escherichia coli and Salvia miltiorrhiza.
abstract: Salinity and drought are important abiotic stresses limiting plant growth and development. Late embryogenesis abundant (LEA) proteins are a group of proteins associated with tolerance to water-related stress. We previously cloned an LEA gene, SmLEA, from Salvia miltiorrhiza Bunge. Phylogenetic analysis indicated that SmLEA belongs to Group LEA14, which is involved in the dehydration response. To determine its function in detail, we have now overexpressed SmLEA in Escherichia coli and S. miltiorrhiza. The logarithmic increase in accumulations of SmLEA proteins in E. coli occurred earlier under salinity than under standard conditions. SmLEA-transformed S. miltiorrhiza plants also showed faster root elongation and a lower malondialdehyde concentration than the empty vector control plants did when cultured on MS media supplemented with 60 mM NaCl or 150 mM mannitol. Moreover, SmLEA-overexpressing transgenics experienced a less rapid rate of water loss. Under either salinity or drought, overexpressing plants had greater superoxide dismutase activity and a higher glutathione concentration. These results suggest that SmLEA may be useful in efforts to improve drought and salinity tolerance in S. miltiorrhiza. Our data also provide a good foundation for further studies into the stress resistance mechanism and molecular breeding of this valuable medicinal plant.
authors.affiliation: Key Laboratory of Medicinal Resource and Natural Pharmaceutical Chemistry of Ministry of Education, National Engineering Laboratory for Resource Developing of Endangered Chinese Crude Drug in Northwest of China, Shaanxi Normal University, Xi'an, 710062, People's Republic of China.
authors.forename: Yucui
authors.initials: Y
authors.lastname: Wu
authors.forename: Congling
authors.initials: C
authors.lastname: Liu
authors.forename: Jing
authors.initials: J
authors.lastname: Kuang
authors.forename: Qian
authors.initials: Q
authors.lastname: Ge
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhezhi
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D055864:Droughts; D004926:Escherichia coli / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D018014:Gene Transfer Techniques; D005978:Glutathione / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics; D054712:Salinity; D055049:Salt Tolerance / Q000235:genetics*; D055051:Salt-Tolerant Plants / Q000235:genetics*; D027561:Salvia miltiorrhiza / Q000235:genetics*; D020539:Sequence Analysis, Protein; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000235:genetics; D013482:Superoxide Dismutase / Q000096:biosynthesis; D014170:Transformation, Genetic; D014867:Water
chemical_list: D010940:Plant Proteins; C066246:late embryogenesis abundant protein, plant; D014867:Water; D012965:Sodium Chloride; D008315:Malondialdehyde; D013482:Superoxide Dismutase; D005978:Glutathione