Cloning And Characteristic Analysis Of MfNAC63 Gene In Medicago Falcata

The Medicago falcata,with excellent stress resistance to drought,cold and salt,is the important germplasm resource and gene pool for cultivating the excellent species.NAC transcription factors widely involved in plant physiological activities and played an important role in plant adaptation to stresses.In this study,a gene Mf NAC63 was cloned based on the RNA-seq data of wild Medicago falcata.Mf NAC63 is a 756 bp nucleotide sequence,encoding a NAC transcription factor of251 amino-acid with a predicted molecular mass of 29.07 k Da.The Mf NAC63 protein has a conserved NAM domain between the 1-75 amino acid positions,which contained five subdomains(A-E)and,this indicated that Mf NAC63 genes belongs to the NAC transcription factor family.Meanwhile,the nuclear localization signal is located in subdomain D of Mf NAC63.Mf NAC63 was predicted no transmembrane domain and signal peptide,and 65.2% probability was localized to the nucleus.Then,the transient expression vector p CAMBIA1300(35S-Mf NAC63-s GFP)was constructed using the vector p CAMBIA1300(35S-s GFP)as a backbone,and the 2epidermal cells of tobacco were injected and observed by laser microscopy.It was found that Mf NAC63 was localized to the nucleus.It was demonstrated that Mf NAC63 has a transcriptional activation function in yeast,and its function domain was located at the C-terminal of protein.The Mf NAC63 was expressed in roots,stems and leaves of wild Medicago falcata,and its expression level in leaves was significantly higher than in roots and stems.Meanwhile,the expression of Mf NAC63 was induced by salt stress or drought stress.These findings indicate that the Mf NAC63 maybe play a role in wild Medicago falcata in response to stress.The overexpression vector p PZP221(35S-Mf NAC63-NOS)was constructed using the vector p PZP221(35S-NOS)as a backbone,and transformation of Medicago sativa and Arabidopsis thaliana were performed.The transformed T1 plantlings of Arabidopsis thaliana were obtained.It could provid experimental materials for further exploration of the function of Mf NAC63.