Date of Completion
Chris Simon; Rachel O'Neill; Paul Lewis; Jonathan Klassen
University Scholar Major
Ecology and Evolutionary Biology
Entomology | Evolution | Genomics | Molecular Genetics
Nutritional symbioses are integral to the survival and diversity of many insects. The majority of herbivorous insects in the order Hemiptera possess stable, inherited symbionts that produce essential amino acids and vitamins. However, instability has been observed in cicadas, with one bacterial symbiont, Hodgkinia cicadicola, being repeatedly replaced by a new fungal symbiont, Ophiocordyceps. The fungal symbionts are thought to be derived from parasitic Ophiocordyceps species, but little is known about these parasitic ancestors or how the transition from parasite to mutualist occurs. We used a combination of targeted amplified genes and metagenomic sequencing to investigate the evolution of endosymbiotic Ophiocordyceps across 25 species of cicadas in the tribe Cryptotympanini. At least four parallel instances of Ophiocordyceps domestication were found in the studied group, arising from a single monophyletic clade of cicada-parasitic Ophiocordyceps with only one having been known previously. The genome of a symbiotic Ophiocordyceps strain from the cicada Megatibicen auletes has been sequenced and annotated, paving the way for future comparative analyses between symbiotic and parasitic Ophiocordyceps.
Vailionis, Jason; Gordon, Eric RL; and Simon, Chris, "Foe to Friend: Parallel Domestication of Ophiocordyceps from Fungal Parasite to Beneficial Symbiont in Cicadas" (2021). University Scholar Projects. 76.