Transcriptome analysis of rice response to blast fungus identified core genes involved in immunity

Rice blast disease caused by the filamentous Ascomycetous fungus Magnaporthe oryzae is a major threat to rice production worldwide. The mechanisms underlying rice resistance to M. oryzae, such as transcriptional reprogramming and signalling networks, remain elusive. In this study, we carried out an in-depth comparative transcriptome study on the susceptible and resistant rice cultivars in response to M. oryzae. Our analysis highlighted that rapid, high-amplitude transcriptional reprogramming was important for rice defence against blast fungus. Ribosome- and protein translation-related genes were significantly enriched among differentially expressed genes (DEGs) at 12 hpi in both cultivars, indicating that the protein translation machinery is regulated in the activation of immunity in rice. Furthermore, we identified a core set of genes that are involved in the rice response to both biotic and abiotic stress. More importantly, among the core genes, we demonstrated that the metallothionein OsMT1a and OsMT1b genes positively regulated rice resistance while a peroxidase gene Perox4 negatively regulated rice resistance to M. oryzae. Our study provides novel insight into transcriptional reprogramming and serves as a valuable resource for functional studies on rice immune signalling components in resistance to blast disease.

Automated summary

The study highlights the importance of rapid, high-amplitude transcriptional reprogramming in rice defense against blast fungus, with ribosome- and protein translation-related genes being significantly enriched among differentially expressed genes at 12 hpi in both susceptible and resistant cultivars. A core set of genes involved in response to both biotic and abiotic stress was identified, including metallothionein genes positively regulating rice resistance and a peroxidase gene negatively regulating it. This study provides novel insights into transcriptional reprogramming and serves as a valuable resource for functional studies on rice immune signaling components in resistance to blast disease.