Functional Analysis Of MfNAC35 Gene In Medicago Falcate

Medicago falcate has the important characteristics such as drought-resistance,cold-tolerance and salt-tolerance.It was an important germplasm resource for resistance breeding and a very important gene pool.The NAC transcription factor is one of the transcription factor families unique to the plants and plays an important role in plant growth,maturation and adaptation to stresses.In this study,the promoter sequence of Mf NAC35 gene was obtained,and the analysis revealed that it contained elements responsible for stresses tolerance regulation.Real-time PCR analysis showed that Mf NAC35 had the higher expression level in the roots of Medicago falcata,and the less expression level in the stems.At the same time,the expression of Mf NAC35 in roots,stems and leaves was up-regulated by salt or drought stress.Yeast experiments showed that Mf NAC35 had transcriptional activation and its functional domain was located at the C-terminus of the protein.The overexpression vector p BI121(35S-Mf NAC35-NOS)was constructed using the plant binary expression vector p BI121(35S-NOS)as a backbone and transformed in-to Nicotiana benthamiana by Agrobacterium tumefaciens-mediated transformation method,and fifteen T0 plantllets were identified by PCR detection.It was found that the Mf NAC35 was expressed in transgenic plantllets via RT-PCR analysis and salt or drought stress could up-regulate the expression of CAT,SOD and P5 CS genes,indicating that Mf NAC35 might regulate the expression of stress-related genes,and then take part in in the regulation of resistance to stresses in plants.