Open AccessOverexpression of Medicago sativa LEA4-4 can improve the salt, drought, and oxidation resistance of transgenic Arabidopsis
Author(s) -
Huili Jia,
Xuemin Wang,
Yonghong Shi,
Xiaoxia Wu,
Yunqi Wang,
Jianning Liu,
Zhihong Fang,
Chunyan Li,
Dong Kuan-hu
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0234085
Subject(s) - abscisic acid , arabidopsis , medicago sativa , biology , abiotic stress , proline , osmotic shock , endosperm , amino acid , biochemistry , oryza sativa , genetically modified crops , subcellular localization , botany , gene , microbiology and biotechnology , transgene , mutant
Late embryogenesis abundant (LEA) proteins are widely involved in many adverse conditions among plants. In this study, we isolated a LEA 4 gene from alfalfa ( Medicago sativa L.) termed MsLEA 4-4 via a homology cloning strategy. MsLEA 4-4 encodes 166 amino acids, and the structural analysis showed that the gene contained five repeating TAQAAKEKTQQ amino acid motifs. There were a large number of α-helix in MsLEA 4-4, and belongs to hydrophilic amino acid. Subcellular localization analysis showed that MsLEA 4-4 was localized in the nucleus. The MsLEA 4-4 promoter consisted of G-box and A-box elements, abscisic acid-responsive elements (ABREs), photo regulation and photoperiodic-controlling cis -acting elements, and endosperm expression motifs. The MsLEA 4-4 overexpressing in Arabidopsis conferred late-germination phenotypes. Resistance of the overexpressed plants to abiotic stress significantly outperformed the wild-type (WT) plants. Under salt stress and abscisic acid treatment, with more lateral roots and higher chlorophyll content, the overexpressed plants has a higher survival rate measured against WT. Compared to those in the WT plants, the levels of soluble sugar and the activity of various antioxidant enzymes were elevated in the overexpressed plants, whereas the levels of proline and malondialdehyde were significantly reduced. The expression levels of several genes such as ABF 3, ABI 5, NCED 5, and NCED 9 increased markedly in the overexpressed plants compared to the WT under osmotic stress.