Advanced search
Start date
Betweenand

Unraveling the origin of the parasitic fungus Escovopsis

Grant number: 21/04706-1
Support type:Scholarships in Brazil - Post-Doctorate
Effective date (Start): June 01, 2021
Effective date (End): May 31, 2023
Field of knowledge:Biological Sciences - Microbiology - Applied Microbiology
Cooperation agreement: NSF - Dimensions of Biodiversity and BIOTA
Principal researcher:André Rodrigues
Grantee:Quimi Vidaurre Montoya
Home Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
Associated research grant:19/03746-0 - Collaborative research: Dimensions US-São Paulo: integrating phylogeny, genetics, and chemical ecology to unravel the tangled bank of the multipartite fungus-farming ant symbiosis, AP.BTA.TEM

Abstract

It is well-known that many specialized parasites originated from generalist ancestors that explored several hosts. Recent findings have shown that this evolutionary process had also occurred in the opposite direction. Considered a parasite of the fungal crops cultivated by attine ants, fungi in the genus Escovopsis (Ascomycota: Hypocreaceae) are associated with colonies of these insects. While the interaction between attine ants and the cultivated fungus originated 50-65 million years ago, evidence suggests that Escovopsis shares a long evolutionary history with these two symbionts. Consequently, Escovopsis would have specialized in parasitizing certain mutualistic fungi, where the host-parasite fidelity would be maintained by chemical mechanisms. In addition, patterns of co-cladogenesis between the mutualistic fungus and Escovopsis were observed in the different fungiculture of the attines, reinforcing that the parasite maintains fidelity with some hosts. Cases of host exchange between Escovopsis strains have been reported by our research group. Such host exchanges occurred in the fungiculture of the derived attines, which cultivate phylogenetically related mutualistic fungi (which may be the reason that allowed such exchanges during evolution). Genomic analyses reinforce the specialization of Escovopsis as parasites of the fungal crops. Escovopsis weberi has a reduced genome, containing few genes related to the degradation of plant polymers, which suggests nutrition derived from the host and not from the plant material accumulated in the colonies of these ants. Evidence from the sequenced genome also indicates that Escovopsis possibly shares a common ancestor with fungi of the genus Trichoderma, which are saprotrophs, i.e., degraders of organic matter, or generalist parasites of other ascomycetes. On the other hand, considering a greater number of fungi genomes of the Hypocreaceae family, it was suggested that Escovopsis shares a common ancestor with parasitic fungi commonly found in basidiomycetes from leaf litter, such as the genera Hypomyces and Sphaerostibella. Therefore, there is still uncertainty about the origin of the parasite Escovopsis and the ancestral groups from which it diverged during evolution. The low sampling of parasitic fungi of basidiomycetes in the tropics made it impossible to identify the groups that Escovopsis potentially diverged. This project aims to gather a collection of fungi from the family Hypocreaceae that parasitize basidiomycetes and, from there, to infer the probable ancestor of Escovopsis. Based on an intense sampling of basidiomycete fungi that occur in different Brazilian biomes, we planned to cultivate the parasitic fungi (if possible) or work with the raw material to test this hypothesis. In addition, to fill an important gap on the origin of Escovopsis, this project will also help studies on the diversification of the genus, providing better outgroups for the Escovopsis phylogenies that are being reconstructed by our research group. (AU)

News published in Agência FAPESP Newsletter about the scholarship: