Microbial Pathogen Effectors in Plant Disease

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.