Analysis Of Salt Tolerance Function Of Alfalfa MsNTF2L Gene

Alfalfa(Medicago sativa)is one of the forage species with a long history of cultivation and the widest distribution area in the world.It has always been known as the "king of forage".However,the increasing salinization of land in Northwest my country has seriously threatened the planting and industrial development of alfalfa.Previous studies have shown that the overexpression of nuclear transport factor MsNTF2L(NUCLEAR TRANSPORT FACTOR 2-like)can significantly improve the drought resistance of Arabidopsis thaliana and alfalfa,but whether it plays an important role in the process of plant response to salt stress is still unclear.Not yet known.In view of this,this study analyzed the salt tolerance of MsNTF2L-transformed Arabidopsis and alfalfa,and obtained the following results:1.The MsNTF2L gene can improve the salt tolerance of Arabidopsis.(1)The overexpression(OE)MsNTF2L Arabidopsis thaliana has greater seed germination rate,seedling root length and fresh weight under salt stress than the wild type(WT);(2)When the salt stress treatment Arabidopsis thaliana matures for 22 days,The leaf morphology of overexpressing MsNTF2L is significantly healthier than that of the wild type;(3)The DAB and NBT staining colors of Arabidopsis leaves are lighter than the wild type after salt stress;(4)The morphology of overexpressing MsNTF2L is significantly increased in Arabidopsis thaliana after salt stress The expression levels of RD20,RD29 A,COR15A,LEA14,P5CS1,CHYR1 genes related to salt/osmotic stress are analyzed.2.MsNTF2L gene can improve the salt tolerance of alfalfa.(1)Alfalfa overexpression lines have stronger salt tolerance than wild type in soil;but interference(RNAi)lines have weaker salt tolerance than wild type lines.(2)The physiological indexes of alfalfa after salt stress were measured,and it was found that the content of total chlorophyll,soluble sugar(KT),and proline(PRO)were OE>WT>RNAi,and the content in malondialdehyde(MDA)was The opposite of.(3)Transcriptome analysis found that the differentially expressed genes involved in ion transport,redox and photosynthesis have obvious differences in the response of wild-type alfalfa and transgenes to salt.3.MsNTF2L is located in the nucleus,endoplasmic reticulum and plasma membrane,and the MsNTF2L protein interacts with the chlorophyll synthetic oxidoreductase protein(MSAD210137).(1)MsNTF2L and no-load were transferred to Nicotiana benthamina,and it was found that the MsNTF2L protein overlapped with the fluorescence of the endoplasmic reticulum and plasma membrane Marker,and there was obvious fluorescence on the nucleus.(2)The MsNTF2L protein and MSAD210137 protein were co-transformed into yeast to confirm the interaction between them.The above results indicate that the MsNTF2L gene can improve the salt tolerance of Arabidopsis and alfalfa,and provide new germplasm and candidate genes for the cultivation of highly stress-resistant alfalfa.