Identification and Characterization of Salt- and Drought-Responsive Family Genes in L.

Aquaporins (AQP) are distributed ubiquitously in plants, and they play important roles in multiple aspects of plant growth and development, as well as in plant resistance to various environmental stresses. In this study, 43 genes were identified in the forage crop All the MsAQP proteins were clustered into four subfamilies based on sequence similarity and phylogenetic relationship, including 17 TIPs, 14 NIPs, 9 PIPs and 3 SIPs. Analyses of gene structure and conserved domains indicated that the majority of the deduced MsAQP proteins contained the signature transmembrane domains and the NPA motifs. Analyses on -acting elements in the promoter region of genes revealed the presence of multiple and diverse stress-responsive and hormone-responsive -acting elements. In addition, by analyzing the available and comprehensive gene expression data of , we screened ten representative genes that were responsive to NaCl or drought stress. By analyzing the sequence similarity and phylogenetic relationship, we finally identified the corresponding ten salt- or drought-responsive genes in , including three , three and four . The qPCRs showed that the relative expression levels of these ten selected genes responded differently to NaCl or drought treatment in . Gene expression patterns showed that most genes were preferentially expressed in roots or in leaves, which may reflect their tissue-specific functions associated with development. Our results lay an important foundation for the future characterization of the functions of genes, and provide candidate genes for stress resistance improvement through genetic breeding in .