The Mechanisms Of OsRBCS And OsUBC2 In Rice Disease Resistance

Rice blast is one of the most important disease in rice production,its damage bring a huge challenge on rice production and food security in our country.Transgenic technique is a new way to exploring and developing new resistance rice varieties.In recent years,a number of disease-related genes were found and characterized,which lays an important foundation for developing high resistance rice varieties.In our laboratory's preliminary work,the OsRBCS and OsUBC2 overexpression and RNAi transgenic rice plants were generated.In this study,we characterized the function of OsRBCS and OsUBC2 in rice defense.Our results showed that the OsRBCS and OsUBC2 gene were up-regulated during the infection of Magnaporthe oryzae and the treatment of JA,SA.The OsRBCS and OsUBC2 overexpression transgenic rice plants enhanced resistance to the infection of M.oryzae,and the PR1,PAL,LOX and PBZ1 defense-related genes were up-regulated in the plants.By contrast,in the OsRBCS and OsUBC2 gene knockdown transgenic rice plants,these defense-related genes were down-regulated,and the plants were more susceptive to the pathogens.Meanwhile,OsRBCS and OsUBC2 also induce the expression of upstream transcription factor WRKY53,WRKY71 and MAPK6.In addition,overexpressing of OsRBCS and OsUBC2 improved the activity of SOD,POD,CAT,the tolerance to salt stress is also improved.Therefore,our results demonstrate that OsRBCS and OsUBC2 genes are relative to rice disease resistance and salt tolerance by taking part in JA?SA signal transduction.