Oomycete intracellular effectors: specialised weapons targeting strategic plant processes

Oomycete phytopathogens have adapted to colonise plants using effectors as their molecular weapons. Intracellular effectors, mostly proteins but also small ribonucleic acids, are delivered by the pathogens into the host cell cytoplasm where they interfere with normal plant physiology. The diverse host processes emerging as 'victims' of these 'specialised bullets' include gene transcription and RNA-mediated silencing, cell death, protein stability, protein secretion and autophagy. Some effector targets are directly involved in defence execution, while others participate in fundamental metabolisms whose alteration collaterally affects defences. Other effector targets are susceptibility factors (SFs), that is host components that make plants vulnerable to pathogens. SFs are mostly negative regulators of immunity, but some seem necessary to sustain or promote pathogen colonisation.

Automated summary

Oomycete phytopathogens use effectors, including proteins and small RNAs, to colonise plants and interfere with normal plant physiology. Effector targets in host cells include gene transcription, cell death, protein stability, and other processes, some of which directly involve plant defence mechanisms. Some effector targets are negative regulators of immunity, while others are necessary for pathogen colonisation.