Identification of differentially expressed genes in rice during its early phases of interaction with Magnaporthe oryzae

Rice blast caused by Magnaporthe oryzae is one of the most destructive diseases causing extensive yield loss throughout the world. The present study deals with identification of stress responsive genes in susceptible rice cultivar HR 12 after challenge with M. oryzae. Transcript profiling using the Affymetrix 57 K GeneChip revealed a total of 72 differentially expressed genes whose expression level was significantly altered under diseased condition. Molecular function enrichment analysis suggested that the differentially regulated genes were mainly related to protein degradation and modification, cell signalling and stressrelated mechanisms. Our study reveals that majority of the genes of protein degradation and modification, transport, signalling and transcription factors are repressed at the initial stages of interaction. The host genes that were induced in response to pathogen infection included hormonal signalling, cell wall defense and transcription factors belonging to the WRKY super family. This study would be helpful in identification of early induced genes in pathogen associated molecular patterns (PAMP)-Triggered Immunity.