Integrated phosphoproteome, ubiquitinome, and acetylome analyses uncovering the post-translational modifications crosstalk during MSP1-induced signaling in rice

Magnaporthe oryzae snodprot1 homologous protein (MSP1) has been shown to act as a pathogen-associated molecular pattern (PAMPs) and trigger PAMP-triggered immunity (PTI) response involving programmed cell death and expression of various defense-related genes in rice. The involvement of several post-translational modifications (PTMs) in the regulation of plant immune response, especially PTI, during pathogen infection is well established, however, the information on the regulatory roles of these PTMs in response to MSP1-induced signaling in rice is currently elusive. Here, we report the phosphoproteome, ubiquitinome, and acetylproteome to investigate the MSP1-induced PTMs alterations in MSP1 overexpressed rice. Our analysis identified a total of 4,666 PTM modified sites in rice leaves including 4,292 phosphosites, 189 ubiquitin sites, and 185 acetylation sites. Among these, PTM status of 437 phosphorylated, 53 ubiquitinated, and 68 acetylated peptides were significantly changed by MSP1. Functional annotation of MSP1 modulated peptides by MapMan analysis revealed that these were majorly associated with cellular immune responses such as signaling, transcription factors, DNA and RNA regulation, and protein metabolism, among others. Taken together, this study uncovers the MSP1-induced PTMs changes in rice proteins and identified several novel components of rice-MSP1 interaction.