The Discussion About The Relationship Between PG And Ethylene Of Tomato By Virus-induced Gene Silence Technology

Virus-induced gene silence is one of the most common gene silence technologies in RNA level. One gene in plant can be made silence by isogeneic defense mechanism which caused by virus.,The phenomenon that the corresponding gene lose its function or has a low level of expression can be induced by structuring a virus carrier which carry a piece of functional gene's cDNA fragment of one kind of plant and infecting the plant by it. So this technology can be used to identify the function of a gene in a short time. In this article, the post harvested mature green tomato: Lycopersicon esculentum cv. Zhongshu was used to be investigated. According to the PG gene sequence announced in NCBI, the PG gene fragment with restriction enzyme cutting site in both ends was amplified. And then it was linked to viral vector of TRV which was going to be transformed into competent Agrobacterium GV3101. With the principle of VIGS, vacuum osmosis with Agrobacterium which contained viral vector was used as the method of infection in order to make the PG gene silence. The amount of ethylene, the activities of PG and ACS were measured from the aspects of both molecule side and physiological side by the technology of Real Time PCR and etc. Meanwhile, the same method was used to silence the ACS2 gene of tomato, which would restrain the generation of ethylene, and then the activity of PG would be measured. Overall, the relationship of PG and ethylene was the point of observed and discussed.According to the research, the amount and the activities of PG and ACS in the samples of PG and ACS2 silenced were lower than the sample of untreated.The virus-induced gene silence of PG and ACS2 had obviously restrainable effect to the generation of ethylene during the ripen process of postharvested mature green tomato fruit. When the ACS2 gene in tomato was silenced, the generation of ethylene was restrained. So it could say that the PG and ACS gene or ACS gene family or ethylene in tomato had influences with each other. Based on the phenomenon that the expression of ACS2 gene was restrained when PG gene was silenced and the expression of PG gene was restrained when ACS2 gene was silenced, one suppose was put forward, which was that PG gene and ACS2 gene or ACS gene family have a same control element. And the relationship between these two genes and the control element was control-feedback mode.