Plant
pathogenic fungi secrete small proteins known as effectors that allow them to
overcome plant defenses and cause disease. Effectors that are conserved in
multiple species of fungi are known as core effectors. Advances in genome
sequencing technologies and Artificial Intelligence/Machine Learning tools have
markedly improved the identification of protein families and the understanding
of their distribution across phylogenetically diverse species. Using these
technologies and tools, we identified potential core effectors in the Fusarium
head blight (FHB) fungus F. graminearum by analyzing the genome
sequences of 199 species that represent all 23 Fusarium species complexes.
Using the program EffectorP, we identified 2,916 genes encoding putative core
effectors from the 199 genome sequences. Subsequently, using the in-silico
secreted protein prediction program SecretSanta, we found that 462 of the
putative effector proteins are likely to be secreted. We also examined the
putative effectors using functional annotation tools and the program AlphaFold
to assess the diversity of their sequences and to determine whether their 3D
structures are similar to known effectors, respectively. Based on these
analyses, we selected 21 putative core effector genes that occur in F.
graminearum and determined that seven were highly expressed during early
stages of wheat head infection. Gene deletion experiments are underway to
assess the role of the seven effector genes in pathogenesis of F.
graminearum on wheat. Understanding the structural diversity and function
of F. graminearum effectors has potential to aid development of FHB
control strategies