Regulation of pattern recognition receptor signalling by phosphorylation and ubiquitination.

Our understanding of how plant innate immunity is triggered and regulated has seen tremendous progress over the last decade, with many important players identified in the model systems Arabidopsis thaliana and Oryza sativa (rice). Identification of these components has come from both genetic screens as well as from proteomics approaches. While genetic approaches are powerful tools of discovery to identify key components in a signalling pathway, the application of genetics is limited when dealing with redundancy or when mutations cause lethal phenotypes. This is where the complementary strength of proteomics has brought major advances. With the advancement in technology in the field of proteomics, not only the proteins involved in innate immune signalling and responses have been identified, but also the posttranslational modifications (PTMs) that these proteins carry have been mapped in more intricate detail and shown to be functionally relevant in both genetic and biochemical terms. Here we discuss the most recent progress in pattern recognition receptor (PRR) signalling with a focus on phosphorylation and ubiquitination.