Comparative Phosphoproteome Analysis of Magnaporthe Oryzae-responsive Proteins in Susceptible and Resistant Rice Cultivars

Biological Significance: Although large-scale identification of phosphorylated proteins has been carried out in rice, there is little report on the rice phosphoproteome in response to pathogens in general and in response to M. oryzae in particular. In this study, a time-course comparative phosphoproteomics was performed to analyze the changes of phosphoprotein profiles in rice leaves during early compatible and incompatible interactions with M. oryzae by using a combination of PEG prefractionation, Al(OH)3-MOAC, 2-DE, Pro-Q DPS and mass spectrometry. Fifty-six M. oryzae-regulated phosphoproteins were identified successfully and phosphorylation within 7 identified phosphoproteins was verified by mapping the phosphorylation sites by nanoLC-MS/MS. Our study provides novel insights into the functions of proteins involved in rice resistance and the molecular mechanism of rice resistance against M. oryzae. Furthermore, we propose the working model for the signaling pathways of rice defense in response to M. oryzae.