SiLEA14, a novel atypical LEA protein, confers abiotic stress resistance in foxtail millet

Abstract

BackgroundLate embryogenesis abundant (LEA) proteins are involved in protecting higher plants from damage caused by environmental stresses. Foxtail millet (Setaria italica) is an important cereal crop for food and feed in semi-arid areas. However, the molecular mechanisms underlying tolerance to these conditions are not well defined.ResultsHere, we characterized a novel atypical LEA gene named SiLEA14 from foxtail millet. It contains two exons separated by one intron. SiLEA14 was expressed in roots, stems, leaves, inflorescences and seeds at different levels under normal growth conditions. In addition, SiLEA14 was dramatically induced by osmotic stress, NaCl and exogenous abscisic acid. The SiLEA14 protein was localized in the nucleus and the cytoplasm. Overexpression of SiLEA14 improved Escherichia coli growth performance compared with the control under salt stress. To further assess the function of SiLEA14 in plants, transgenic Arabidopsis and foxtail millet plants that overexpressed SiLEA14 were obtained. The transgenic Arabidopsis seedlings showed higher tolerance to salt and osmotic stress than the wild type (WT). Similarly, the transgenic foxtail millet showed improved growth under salt and drought stresses compared with the WT. Taken together, our results indicated that SiLEA14 is a novel atypical LEA protein and plays important roles in resistance to abiotic stresses in plants.ConclusionWe characterized a novel atypical LEA gene SiLEA14 from foxtail millet, which plays important roles in plant abiotic stress resistance. Modification of SiLEA14 expression may improve abiotic stress resistance in agricultural crops.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-014-0290-7) contains supplementary material, which is available to authorized users.

Genome-Wide Identification, Characterization, and Stress-Responsive Expression Profiling of Genes Encoding LEA (Late Embryogenesis Abundant) Proteins in Moso Bamboo (Phyllostachys edulis)

“…Although little is known of their function, some reports indicated that they will accumulate in response to diverse stresses in plants, such as cotton ( LEA14-A ) [38], Craterostigma plantagineum ( PcC27-45 ) [40], soybean ( D95-4 ) [41], tomato ( ER5 ) [42], and Arabidopsis (LEA14) [43], etc. Overexpression of CaLEA6 in tobacco improves tolerance to dehydration and NaCl [44]; Transgenic sweetpotato non-embryogenic calli that overexpressed IbLEA14 showed increased tolerance to drought and salt stress by enhancing lignification [45]; Overexpression of SiLEA14 foxtail millet improved tolerance to salt and drought [46]. All these results suggest that LEAs of group LEA_2 proteins are also closely associated to the resistance to multiple abiotic stresses.…”

A Non-specific Setaria italica Lipid Transfer Protein Gene Plays a Critical Role under Abiotic Stress

“…pSuper1300-GFP was used as the control. Maize protoplasts were prepared and transformed as described by Wang et al (2014). Green fluorescent protein (GFP) signals were observed using a confocal laser scanning microscopy (LSM 510, Carl Zeiss MicroImaging GmbH, Jena, Germany).…”

“…The free proline contents were measured as described by Bates et al (1973) and Wang et al (2014). 0.05 g dry leaf tissue was used.…”

“…Soluble sugar contents were examined according to Yemm and Willis (1954) and Wang et al (2014). 0.1 g dry leaf tissue was used for the extraction of soluble sugar.…”

Drought Adaptation in Millets

“…Wang et al [75] indicated that the overexpression of SiLEA14, a type of LEA gene from foxtail millet, increased the tolerance of Arabidopsis plants to salt and osmotic stress. Parvathi et al [76] reported the induction of several genes when finger millet was exposed to drought.…”