| Brassica napus is the main oil crop planted in China,but it is often infected by various pathogens,resulting in the decline of rape yield year by year.Therefore,how to improve the resistance of rape to pathogens on the premise of ensuring yield and quality has become one of the urgent problems to be solved.Previous studies have shown that Arabidopsis thaliana exa1 regulates plant resistance to pathogens at the post-translational level.As both Arabidopsis and rape are cruciferous plants,the research on At EXA1 in Arabidopsis provides ideas and basis for study of BnaEXA1 in oil rape.The regulatory effects of BnaEXA1 on plant disease resistance were preliminarily revealed by means of genetics and molecular biology in the paper.The main results are as follows:1.There are two copies of BnaEXA1 in oil rape,which are Bna A09.EXA1 and Bna CNN.EXA1,respectively.Through bioinformatics analysis and re-sequencing analysis,it is found that both Bna A09.EXA1 and Bna CNN.EXA1 have conserved GYF domain and Y-X4-l-l motif,indicating that it plays an important role in plant disease resistance.2.CRISPR knockout mutant and overexpression lines of BnaEXA1 were generated by Agrobacterium mediated hypocotyl transformation,and 12 CRISPR and 12 overexpression positive seedlings were obtained.Among them,CRISPR positive seedlings had no gene editing,while six were Bna A09.EXA1 overexpression positive seedlings,the other six were Bna CNN.EXA1 overexpression positive seedlings which provide new germplasm resources for resistance breeding of oil rape.3.The overexpression vector of Bna A09.EXA1 or Bna CNN.EXA1 was transformed into exa1-2 mutant in Arabidopsis,which reduced the resistance of exa1 to Sclerotinia sclerotiorum and Hyaloperonospora arabidopsidis(H.a.)Noco2,and the expression of PR1 also decreased to the wild-type level,indicating that the function of BnaEXA1 is similar to At EXA1 and can genetically rescue exa1 phenotype in Arabidopsis.4.Through yeast two hybrid experiments,it was found that Bna A09.EXA1 and Bna CNN.EXA1 could interact with the homologous genes of At EIF4 E in oil rape,Bna A01g08910 D and Bna C08g11130 D,and the homologous genes of At RPL18 in oil rape,LOC111203407,Bna C02g39900 D and Bna C07g28280 D.It is postulated that BnaEXA1 also regulates plant resistance to pathogen at the post-translational level. |
