Symposium 5: Animal-Associated Fungi -- From Parasitism to Mutualism 13:30 - 15:30 Wednesday, 14th August, 2019 Meridian AB

13:30 - 14:00

WED 6 Genomic insights into the - interactions, using the example of Diptera gut symbionts—

Yan Wang1,2, Matt Stata2, Wei Wang2, Jason Stajich1, Merlin White3, Jean-Marc Moncalvo2 1University of California, Riverside, Riverside, USA. 2University of Toronto, Toronto, Canada. 3Boise State University, Boise, USA

Abstract

The increasing genomic resources of entomopathogenic fungi have advanced our knowledge regarding fungal biology and their interactions with insect hosts in the last decade. However, our understanding of the insect commensal fungi still lagged behind with little genomic information, especially for the early-diverging lineages, like Harpellales (, Zoopagomycota). Harpellales are common fungal endobionts associated with digestive tracts of immature aquatic stages of various Diptera, including black flies, midges, and mosquitoes. Harpellales have been estimated to have an ancient origin with their Diptera hosts. Their long- term association may have left genomic hallmarks that deserve careful examination. We have sequenced and annotated nine whole-genome sequences of Harpellales fungi and conducted the first comparative genomics within the as well as with entomopathogenic ones across the fungal tree of life. Harpellales genomes feature low GC content (26-37%) and present large genome size variations (25-102 Mb). We identified a gene toolbox presumably essential to the fungus-insect symbiosis, which is utilized by both insect-pathogenic fungi ( and Zoopagomycota) and commensals (Harpellales) but absent in free-living relatives (Kickxellomycotina). Our results not only narrowed the genomic scope of fungus-insect interactions from several thousand genes to eight core players but also distinguished host invasion strategies employed by insect commensals and pathogens. The genomic content suggests that insect commensal fungi rely mostly on adhesion protein anchors that target the digestive system of , while entomopathogenic fungi maintain more transmembrane helices, signal peptides, and pathogen-host interaction genes to inactivate the host inflammation system and suppress the host defense. 14:00 - 14:30

WED 7 Potential new reservoir hosts: a study with Ophidiomyces ophiodiicola and Nannizziopsis guarroi

Savannah Gentry1, Anne Pringle2, Jeffrey Lorch3 1Department of Botany, Univeristy of Wisconsin, Madison, USA. 2Department of Botany and Bacteriology, Univeristy of Wiscon, Madison, USA. 3National Wildlife Health Center, Madison, USA

Abstract

Ophidiomyces ophiodiicola and Nannizziopsis guarroi are fungal pathogens responsible for devastating and often fatal infections in reptiles. O. ophiodiicola is the primary agent of snake fungal disease and an emerging infectious disease. N. guarroi is often associated with fatal epidermal infections in lizard , for example veiled chameleons and iguanas. Because other fungal diseases, including white nose syndrome and chytridiomycosis, are causing extreme declines in wildlife biodiversity, we are concerned about the potential for O. ophiodiicola to spread to naïve populations and its ability to infect hosts other than snakes. Prior to our experiment, we completed the University of Wisconsin-Madison institutional animal care and use committee (IACUC) regulations. We then conducted an infection trial using 12 adult corn snakes and 12 juvenile bearded dragons, species chosen because of their close phylogenetic relationship to one another. Our experiment involved a cross inoculation using one strain of O. ophiodiicola and one of N. guarroi each given to a group of corn snakes and a group of bearded dragons. As expected, O. ophiodiicola caused visible infection in snakes, but not in lizards. Similarly, N. guarroi caused visible infection in lizards (fulfilling Koch’s postulates), but not in snakes. However, after animals were euthanized, we placed excised skin pieces on test medium, and discovered each pathogen was able to colonize the skin irrespective of host species. Our results suggest that both snakes and lizards are potential reservoir hosts i.e. hosts that can maintain the fungus without becoming infected.

14:30 - 15:00

WED 8 Looking for truffles: exploring symbiotic mycophagy in two birds endemic to Patagonia

Marcos V Caiafa1, Michelle Jusino1, Iván Díaz2, Matthew Smith1 1University of Florida, Gainesville, USA. 2Universidad Austral de Chile, Valdivia, Chile

Abstract

Ectomycorrhizal fungi play key roles in forests by feeding nutrients to the roots of trees in exchange for sugars. Some of these fungi form underground mushrooms called truffles that rely on animals for spore dispersal. Most truffles produce strong odors to attract mammals which dig them up, eat them, and spread the spores in their feces. Temperate rainforests of southern South America are dominated by Nothofagaceaetrees that depend on truffles for nutrients, but mammals are relatively scarce and truffles in this system do not produce strong odors. However, the truffles resemble fruits, suggesting that they are dispersed by animals that eat fruit and rely on sight rather than smell to find food. The objective of this study is to document the symbiosis between two understory birds: Chucao Tapaculo (Scelorchilus rubecula) and Black-throated Huet-huet (Pteroptochos tarnii) and several species of endemic truffle fungi inNothofagaceaeforests. We documented the diet of the birds by microscopically and molecularly analyzing fecal samples. Standard microscopy methods were used to confirm, identify, and quantify spores in the fecal samples. We used high-throughput amplicon sequencing (HTS) to identify fungi by sequencing ITS and LSU. Our HTS results confirmed the presence of at least 29 ectomycorrhizal fungi in the fecal samples, including nine truffle-like fungi. Some taxa detected are Cortinarius(Thaxterogaster)sp., Descolea brunnea, Melanogastersp., Hysterangiumsp., Ruhlandiella patagonicaand Cystangium nothofagi. These results suggest a putative case of avian mycophagy where both chucaos and huet-huets eat truffle-like fungi and disperse spores. 15:00 - 15:30

WED 9 Heart Rot Hotel 2: a synthesis of the symbioses between fungi and woodpeckers across North America

Michelle Jusino University of Florida, Gainesville, USA

Abstract

Fungi, woodpeckers, and tree cavities are intricately entwined. Historically, studies of these relationships relied upon visual observation of fungal fruiting bodies, tree decay class categorization, and limited culturing work. These methods provided some insights, but left fundamental questions about woodpeckers and fungi unanswered. How many fungi are associated with woodpeckers? How common and widespread are these relationships? Do woodpeckers facilitate fungal dispersal, or do they select trees with certain fungal inhabitants? High-throughput amplicon sequencing (HTAS) provides more accurate and effective characterization of the fungi associated with tree cavities and woodpeckers. Here we use HTAS to study the fungal communities associated with woodpeckers across North America, covering a range of ecologies and management needs. First, we compared the symbiotic relationship between endangered red-cockaded woodpeckers and fungal communities in pines of the Southeastern United States, to relationships between acorn woodpeckers and fungi in oaks of California. We then looked across fungal communities in cavities excavated by four additional woodpecker species in the Pacific Northwest. We saw a similar pattern across different birds and ecosystems – trees with cavities excavated by woodpeckers have fungal communities that are distinct from fungal communities in trees without excavations. Some woodpecker species appear to select trees with certain fungi for excavation, others facilitate fungal dispersal during excavation, and some do both. Taken together, these results illustrate that associations between woodpeckers and fungi are widespread among species, geography, and ecoregions. These data serve as a first step towards answering larger-scale questions about global associations between woodpeckers and fungi.