Research On Bidirectional Promoter Of Tomato Yellow Leaf Curl Virus

In recent years, as global warming, economic growth and development of agricultural international trade, the spread of mediator whiteflies obtained unprecedented expansion,Geminiviruses also intensified, large outbreak in the world, endangering more food and cash crops, causing heavy economic losses.Early in the year we found two strains of different tomato yellow leaf curl virus(TYLCV) intergenic region(IR region) natural deletion mutants BJ4 and BJ6, difference with the normal length of strains BJ3 on symptoms at early onset.Construction of infectious clones TYLCV-BJ3, TYLCV-BJ4, TYLCV-BJ5, TYLCV-BJ6, each of a strain has 1.2A and 1.4A.Pathogenicity experiments show, all of the TYLCV infectious clones BJ3-1.2A 、BJ4-1.2A、BJ5-1.2A、BJ6-1.2A、BJ3-1.4A、BJ4-1.4A、BJ5-1.4A、BJ6-1.4A can systematically infected tomato(M82) the original host and showed clear symptoms of flu disease, and can infect the N. benthamiana systematic but can not infect leaf tobacco.In the early stages, vaccinated BJ4 and BJ6 tomato seedlings show obvious severe disease symptoms than that inoculated BJ3 and BJ5.The same strain of 1.2A and 1.4A of infectious clones no significant difference in pathogenicity.While building the TYLCV bidirectional promoter complementary strand direction GUS expression vector.Promoters in both directions could express the GUS gene in roots, stems, leaves cortical parenchyma cells, vascular tissue phloem cells, mesophyll cells.Complementary strand direction promoter expression is stronger than the virus chain direction, and BJ4 promoter expression activity is stronger than BJ3 the normal length promoter, almost the same expression pattern.The lack analysis of the stem-loop structure and some key elements of IR region is experimenting further.1.2A of the full-length infectious clones can infect the host systematicly that provide evidence for the next build 1.0A infectious clones ends only with IR region.The TYLCV bidirectional promoter we identified is important for plant disease resistance genetic engineering, it can be an effective promoter that drives expression of resistance genes in a plant and widely used in plant genetic engineering.