Oomycete pathogens encode RNA silencing suppressors

Wenbo Ma and colleagues show that two effectors from the oomycete plant pathogen Phytophthora sojae suppress RNA silencing in plants by inhibiting the biogenesis of small RNAs. These findings show that some eukaryotic pathogens, like their prokaryotic and viral counterparts, have evolved virulence proteins that target host RNA silencing processes to promote infection.