The elicitor-responsive gene for a GRAS family protein, CIGR2 , suppresses cell death in rice inoculated with rice blast fungus via activation of a heat shock transcription factor, OsHsf23.

We show that a rice GRAS family protein, CIGR2, is abonafidetranscriptional activator, and through this function, targets the B-type heat shock protein-encoding geneOsHsf23(Os09g0456800).CIGR2(Os07g0583600) is anN-acetylchitooligosaccharide elicitor-responsive gene whose activity, through the direct transcriptional control ofOsHsf23, is required for mediating hypersensitive cell death activation during pathogen infection. RNAi lines ofCIGR2andOsHsf23similarly exhibited the higher level of granulation in the epidermal cells of leaf sheath inoculated with an avirulent isolate of rice blast fungus. Interestingly, we did not observe altered levels of resistance, suggesting that CIGR2 suppresses excessive cell death in the incompatible interaction with blast fungus via activation ofOsHsf23. N-Acetylchitooligosaccharides-responsiveCIGR2suppresses cell death of rice in cooperation withOsHsf23. [ABSTRACT FROM PUBLISHER]