The Functional Analysis Of Rice Blast Disease Defense-related Gene OsGRP1

Rice blast is one of the most important rice diseases,which can cause a huge loss on rice production worldwide and is difficult to control.Studying on molecular mechanism of rice resistance to blast fungus,which can lay a foundation for cultivating disease-resistant varieties by transgenic technology.Previous studies suggested that a glycinerich protein(GRP)gene could be induced by rice blast infection.In this paper,we study further the function of the gene in rice resistance by using the method of gene overexpression and silencing.Firstly,the overexpression vectors of OsGRP1 gene were constructed,and then,the overexpression vectors of OsGRP1 were transformed into rice Nipponbare by Agrobacterium.Ten transgenic lines were obtained.After PCR amplification of hyg resistance gene and testing the relative expression level of OsGRP1 in transgenic rices by QRT-PCR,9 transgenic lines showed to be successful transformed.An evaluation of disease resistance have been detected in positive transgenic rice,it showed that the overexpression of OsGRP1 in rice could increase the resistance against the rice blast.The results suggest that OsGRP1 play a role in rice resistance.Further analysis of the results showed that OsGRP1 could be induced after Magaporthe grisea(GUY11)infection,and treatment by SA and JA,respectively.Meanwhile,the relative expression of rice disease response genes of PAL?PR1?PBZ1 and LOX,which associated with SA and JA pathway were increased in the transgenic rice plants.Therefore,the OsGRP1 may involve in rice resistance by regulating the SA and JA pathway.To further confirm its function,the RNAi vectors of OsGRP1 have been constructed,and transformed into Agrobacterium cells,and which will be used to transform rice seeds to get OsGRP1 silencing plants.