Microbial Pathogen Effectors in Plant Disease

Abstract

Microbial plant pathogens use secreted effector proteins for successful infection of their host. This evolved state is rather exceptional as most microbes do not cause disease in the vast majority of plant species. An important primary activity of effectors is to interfere with a range of plant immune processes to evade and suppress pathogen detection, or to block immune signalling and downstream responses. Furthermore, effectors can enhance disease susceptibility by altering cellular processes and modulating host transcription. For most of these activities, effectors specifically target plant proteins that are central in these processes. An advanced virulence strategy is the post-translational modification by effectors of plant targets to change their activity or stability. The knowledge gathered on the molecular mechanisms underlying effector-triggered susceptibility of plants provides great potential for novel approaches of resistance breeding.