Study On Introduction Of XIOsPR10 Gene Into Rice And The Functional Analysis Of XIOsPR10

It has been regarded that there are closed relationship between PR10s and systemic acquired resistance (SAR). And PR10s always shows its transcriptional activity when plant response to pathogen infection. Many studies showed that PR10s played an important role in plant defense response. In order to study the function of rice XIOsPR10 gene and its effects in plant resist disease reaction more clearly, we constructed plant over expression vector and RNAi expression vector of XIOsPR10 of rice. Then, the recombinant plasmids were integrated into the genome of rice via Agrobacterium tumefaciens EHA105 mediation respectively. We also got the fusion protein His-XIOsPR10 by Prokaryotic Expression, and research its RNase activity. These researches provide a basis for further study on XIOsPR10.Firstly, we constructed plant over expression vector p1301-35S-XIOsPR10-Tnos and RNAi expression vector pDS1301-XIOsPR10 according the cDNA of XIOsPR10 of rice. Then, the XIOsPR10 gene and the RNAi fragment were integrated into the genome of rice via Agrobacterium tumefaciens EHA105 mediation and rice effective transformation system respectively. Results indicated that the recombinant plasmids have been expressed and transferred into rice cultivars (Zhong hua11) with PCR analysis, southern dot blotting and GUS gene expression detection. The mRNA transcription levels of XIOsPR10 in regenerated plant were detected by semi-quantitative RT-PCR, the results shows that the transcription levels of XIOsPR10 in over expression transgenic rice were higher than WT, this indicates that XIOsPR10 can be expressed stably. Furthermore, some RNAi transgenic rice don't express XIOsPR10 in mechanical stress condition. It shows that XIOsPR10 was total knocked out successfully. But we also found that the interfering efficiency of some RNAi transgenic rice is inconspicuousness.Furthermore, many PR10 proteins have been reported to exhibit ribonuclease activity. Researches have shown in vitro translation inhibitory activity for Panax RNase and predicted it to be responsible for its antibiotic activity. So we constructed a Prokaryotic Expression Vector pET28a-XIOsPR10. The E.coli BL21(DE3) contained the expression plasmid was induced by 0.8mM IPTG.. And the fusion protein His-XIOsPR10s were purified with magnetic microbeads. But the further experiment of bacteriostatic showed that the purified fusion protein have not the antibiotic activity. Whether the fusion protein has the antibiotic activity or other functions need further research.