Comparative Nuclear Proteomics Analysis Provides Insight into the Mechanism of Signaling and Immune Response to Blast Disease Caused by Magnaporthe oryzae in Rice.

Modulation of plant immune system by extrinsic/intrinsic factors and host-specific determinants fine-tunes cellular components involving multiple organelles, particularly nucleus to mount resistance against pathogen attack. Rice blast, caused by hemibiotrophic fungus Magnaporthe oryzae, is one of the most devastating diseases that adversely affect rice productivity. However, the role of nuclear proteins and their regulation in response to M. oryzae remains unknown. Here, the nucleus-associated immune pathways in blast-resistant rice genotype are elucidated. Temporal analysis of nuclear proteome is carried out using 2-DE coupled MS/MS analysis. A total of 140 immune responsive proteins are identified associated with nuclear reorganization, cell division, energy production/deprivation, signaling, and gene regulation. The proteome data are interrogated using correlation network analysis that identified significant functional modules pointing toward immune-related coinciding processes through a common mechanism of remodeling and homeostasis. Novel clues regarding blast resistance include nucleus-associated redox homeostasis and glycolytic enzyme-mediated chromatin organization which manipulates cell division and immunity. Taken together, the study herein provides evidence that the coordination of nuclear function and reprogramming of host translational machinery regulate resistance mechanism against blast disease.