Comparative nuclear proteomics analysis provides insight into the mechanism of signaling and immune response to blast disease caused by Magnoporthe oryzae in rice

Abstract

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, we elucidate the nucleus-associated immune pathways in blast resistant rice genotype. Temporal analysis of nuclear proteome was carried out using 2-DE coupled MS/MS analysis. A total of 140 immune responsive proteins (IRPs) were identified associated with nuclear reorganization, cell division, energy production/deprivation, signaling and gene regulation. We interrogated the proteome data using correlation network analysis that identified significant functional modules pointing towards immune related coinciding processes through a common mechanism of remodelling 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, our study provides evidence that coordination of nuclear function and reprogramming of host translational machinery regulate resistance mechanism against blast disease.