Subcellular Localization Of Silencing Suppressors Encoded By Rice Stripe Virus And Construction Of RNAi Transgenic Rice

Rice stripe virus (RSV) is the representative member of the genus Tenuivirus, NS2and NS3encoded by RSV were gene silencing suppressors. Gene silencing suppressor always has a nuclear localization signal and localizes in the nucleus, playing roles in the process of viral infection and diffusion. Most of silencing suppressors are pathogenesis-related factors, which accelerate the viral movement and accumulation. RDR1, a endogenous gene of plant, shows the desease-resistance to some plant viruses. In this paper, the subcellular localization of NS2and NS3were observed, NS(2+3)-RNAi and RDR1-RNAi transgenic plants were constucted and identified, then the RSV resistance of transgenic plants were evaluated. The resluts lay a good foundation for further study of these three genes.This paper comprises two parts. In the first part, the subcellular localization of silencing suppressors encoded by RSV were observed. In the second part, RNAi technique was employed to construct the NS(2+3)-RNAi and RDR1-RNAi transgenic rice, then the resistance to RSV of transgenic rice were analyzed. The main resluts as follows:1. Both NS2and NS3were localized in nucleus. In the nucleus, only NS2can form spherical particles, the further experiments showed that NS2can co-localize to cajal body.2. NS(2+3)-RNAi and RDR1-RNAi T0transgenic rice were obtained. These transgenic plants were identified through RT-PCR、qPCR and southern blot methods.3. To some extent, NS(2+3)-RNAi T0transgenic rice showed resistance to RSV. Compared with the CK plants, the appearance of symptoms in T0transgenic rice was delayed by12days, on average, suggesting that the gene silencing suppressors of RSV possibly involved in viral infection.