Cloning and expression analysis of a novel Glutathione S-transferase gene, MsGST, from alfalfa (Medicago sativa)

Jie An; Peizhi Yang; Yuman Cao; Jincai Geng; Penghui Ren; Zhang You; Yafang Wang; Zhiqiang Zhang; Jieyu Yang

Jie An Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Peizhi Yang Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Yuman Cao Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Jincai Geng Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Penghui Ren Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Zhang You Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Yafang Wang Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Zhiqiang Zhang Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China
Jieyu Yang Department of Grassland Science, College of Animal Science and Technology, Northwest AandF University, Yangling, Shaanxi 712100, China

Keywords: Medicago sativa, cloning, expression, glutathione S-transferase, abiotic stress

Abstract

Glutathione S-transferases are important enzymes in protecting cells by scavenging reactive oxygen species induced by various stresses. In this study, a novel GST gene, MsGST (KM044312), was cloned and characterized from alfalfa. The open reading frame of MsGST contains 660bp nucleotides, encoding 219 amino acid residues. Amino acid sequence alignment indicated that the deduced MsGST protein was highly homologous to other plant tau class GST sequences. According to amino acid phylogenetic analysis, the MsGST gene was clustered into the same branch with other legume plants. Real-time quantitative PCR (qRT-PCR) revealed that the expression levels of MsGST were up-regulated in both shoots and roots under ABA treatment and various stresses, including salt, drought, cold and heat stress. The effect of nodules on MsGST gene expression indicated that the induction of MsGST expression by abiotic stress is independent of rhizobium symbiosis. In conclusion, the MsGST gene may be involved in response to different abiotic stresses in alfalfa.