Abstract
The rice Pish gene confers resistance against rice blast Magnaporthe grisea expressing avrPish. We applied rice lines mutagenized with rice retrotransposon Tos17 for forward screening and isolated Pish gene which belongs to NBS-LRR class of R genes. RNA analysis revealed that the expression level of Pish was barely low and not altered after fungus inoculation. Transient expression of Pish in N. benthamiana caused weakly cell death and ROS production. The genomic sequence and Tos17 FST data base revealed that other three NBS-LRR genes are arranged tandemly beside Pish and this R gene cluster is one of the hot spots of Tos17 insertion. Unexpectedly, the insertions of Tos17 distribute not evenly in spite of the structural similarity among four NBS-LRR genes in this region, suggesting that R genes likely prefer to accumulate any mutations for its evolution.
