There are more than thousand of known fungal species capable of killing insects, most of which are ascomycete fungi. The species like Metarhizium anisopliae, M. robertsii, M. acridum and Beauveria bassiana have been developed as eco-friendly biological control agents against different insect pests. The species of Cordyceps militaris and C. sinensis (syn. Ophiocordyceps sinensis), however, are best known as traditional Chinese Medicines that have been used for hundreds of years in Eastern countries.
Our group is mainly focused on the studies of these fungi at genomics, and functional genomics levels to understand the strategies/mechanisms employed by the fungi to evade host immunity. We sequenced the genomes of more than 20 species of the ascomycete entomopathogenic fungi, and the phylogenomic analyses indicate that fungal entomopathogenicity has evolved multiple times, but with a similar expansion of protease and chitinase protein families etc., an indication of convergent evolution during fungal adaptation to insect hosts. Gene functional studies are focused, in particular, on fungal effectors involved in suppressing host immune defenses. We are also interested in exploring the chemical biology of bioactive secondary metabolites produced by these fungi, and the mechanism of fungal culture degeneration. Our ongoing studies have revealed that insect pathogenic fungi have to outcompete insect cuticular microbiomes prior to penetrating insect cuticles, therefore the multipartite interactions among fungi, insects, and insect microbiotas. Based on the understanding of multipartite interactions, genetic engineering of these fungi will facilitate the improvement of the potency of mycoinsecticides.
Insect cadavers mycosed or colonized by Metarhizium robertsii, M. acridum, Beauveria bassiana,Ophiocordyceps sinensis, Cordyceps militaris and C. cicadae , respectively.
Fungus-insects-ectomicrobiome interactions as reviewed in Annu Rev Entomol (2017); Curr Opin Microbiol (2023); PLoS Pathol (2024) and Trends Microbiol (2024).