This research article investigates the evolution of effector proteins, secreted proteins that fungal pathogens use to infect plants. The study focuses on sequence-unrelated structurally similar (SUSS) effectors, proteins that share similar structures but have very little sequence similarity, highlighting how these effectors have evolved through divergent evolution and domain fusion. The researchers used AlphaFold2 to predict the structures of 26,653 secreted proteins from 21 fungal species and employed a combination of sequence and structure-based similarity searches to cluster these proteins into families. They found that obligate biotrophs (fungi that depend entirely on their host for survival) exhibited particularly high expansion of SUSS effector families, suggesting unique evolutionary pressures. The study reveals several novel SUSS effector families and suggests that common motifs present in these families likely arose through the extreme expansion and divergence of related proteins, not through independent evolution. This research provides a significant contribution to understanding how fungal pathogens adapt and evolve their effector proteins to overcome plant immunity.
Source: Prediction of effector protein structures from fungal phytopathogens enables evolutionary analyses
Kyungyong Seong & Ksenia V. Krasileva
doi: https://doi.org/10.1038/s41564-022-01287-6
