Patterns of genotype-specific interactions in an obligate host-specific insect pathogenic fungus
Data files
May 27, 2025 version files 258.26 KB
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AllFlies_CoxFormat2020.csv
252.48 KB
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coordinates.csv
420 B
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HazardRatiosForHeatMap.csv
1.99 KB
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README.md
2.30 KB
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total_mortality_proportion.csv
1.07 KB
Abstract
Host-pathogen infections and possible effects on co-evolutionary patterns depend on the genotypes of both host and pathogen. Obligate fungal pathogens of plants are often characterised by host-pathogen genotype-by-genotype (GxG) interactions, but whether these patterns exist in obligate-insect fungal pathogens are unclear. We take advantage of the obligate insect pathogenic fungus Entomophthora muscae, where individual isolates are specific to different dipteran host species in nature but can cross-infect multiple fly species in the laboratory. We collected three new isolates of E. muscae from Drosophila species. Phylogenetic analysis showed that Drosophila-isolated E. muscae represent a distinct geographically widespread Drosophila-lineage compared to house fly (Musca domestica) or Delia species-isolated E. muscae. We used the three new E. muscae isolates from Drosophila spp. together with a genetically distinct E. muscae isolate from house flies and assessed their virulence in a cross-infection experiment using one house fly, three D. suzukii and two D. melanogaster genotypes as hosts. All fungal isolates successfully infected hosts, induced behavioural manipulation, sporulated in all fly hosts, and differed in virulence between host genotypes, revealing GxG interactions. While house flies were most susceptible to fungal infection with 99% mortality, we found a lower virulence of 49% and 25% mortality in D. melanogaster and D. suzukii genotypes, respectively. Furthermore, all isolates harboured a specific mycovirus (family Iflaviridae), but co-phylogenetic branching patterns did not support fungus-virus co-speciation. We show that the genetic makeup of both fungal pathogen and fly host influence E. muscae infectivity, confirming GxG interactions in obligate fly fungal pathogens.
There are four annotated datasets: coordinates.csv; AllFlies_CoxFormat2020.csv, HazardRatiosForHeatMap.csv, total_mortality_proportion.csv
Description of the data and file structure
The coordinates.csv dataset was used to illustrate the map in Figure 1.
Table of contents for coordinates.csv
- organism: Fungus or Host (dipteran)
- genotype: Detail about which fungus or host fly genotype
- latitude: latitudinal coordinates of collection location
- longitude: longitudinal coordinates of collection location
The AllFlies_CoxFormat2020.csv dataset was used in virulence analyses and to generate Figure 3, S1-S3.
Table of contents for AllFlies_CoxFormat2020.csv
- Species: dipteran host species
- Genotype: dipteran host genotype
- Isolate_fullName: fungal isolate ID
- Isolate: fungal isolate ID abbreviated
- Infection_date: date of exposure to sporulating or freeze-killed cadavers
- Cadaver_deathday: the day post infection at which the cadaver died (6dpi or 7dpi)
- Total_flies: Total number of flies used in the replicate
- Day: day post infection of data collection (from 1 to 7)
- FlyID: ID code for each of the flies per container
- Pot: experimental container number
- Status: mortality status 0=alive, 1=dead (binary 0/1)
The HazardRatiosForHeatMap.csv dataset was used to generate the heatmaps and GxG plots for Figure 4 & S4-S5.
Table of contents for HazardRatiosForHeatMap.csv
- fungus: fungal isolate ID
- type: genotype or phenotype (species): referring to comparisons of fungal genotype to host for which the hazard ratios were extracted
- fly_species: dipteran host species
- fly_line: dipteran host genotype
- hazard_ratio: hazard ratio extracted from the exp(coef) values of the coxme model outputs
The total_mortality_proportion.csv dataset was used to determine the mortality rate and the generate Figure S4.
Table of contents for total_mortality_proportion.csv
- Host: dipteran host species
- Genotype_long: dipteran host genotype
- Genotype: dipteran host genotype abbreviated
- Isolate: fungal isolate ID
- Alive: Total number of flies still alive at the end of the experiment (10 dpi)
- Dead: Total number of flies dead at the end of the experiment (10 dpi)