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Updated: Sep 28, 2026
Generation of Monoclonal Cultures from Wolbachia-infected Drosophila melanogaster JW18 Cell Line
Published on: June 27, 2025
Wolbachia interactions that determine Drosophila melanogaster survival
1Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA. Adam_Fry@Brown.edu
Abstract:
We have recently described a mutualistic symbiosis in which Wolbachia bacteria were shown to improve the fitness of some Drosophila melanogaster stocks. Wolbachia did not extend longevity in all Drosophila genotypes, even though 16s rDNA sequences indicated that our Drosophila stocks were infected with the same Wolbachia strain. Here, we use reciprocal hybrid crosses between two Drosophila strains, one that lived longer with Wolbachia (Z53) and one that did not (Z2), to investigate the inheritance of the survival phenotype and its dependence on the host genotype, sex, and mating conditions. Wolbachia's positive effects were more apparent in hybrid flies than in parental flies, ruling out exclusive maternal inheritance or the dependence of the survival phenotype on Wolbachia strain differences. The Wolbachia survival effects were more apparent in single-sex cages, where courtship and mating were not permitted. In these cages, nearly all flies with Wolbachia lived longer than uninfected flies, even though strain Z2 showed no Wolbachia effect in mixed-sex mating cages. We used comparisons between single- and mixed-sex cages to estimate the cost of reproduction for both sexes. Our data suggest that Wolbachia infection may increase the inferred cost of reproduction, particularly in males. Wolbachia can even produce a positive survival effect almost as large as the negative survival effect associated with reproduction. We discuss the implications of our experiments for the study of insect symbioses.
Insights
Wolbachia bacteria can improve Drosophila melanogaster survival, but this effect depends on host genotype and mating conditions. Reproduction incurs a survival cost, especially for males, which Wolbachia may exacerbate.
Area of Science:
- Microbial Symbiosis
- Genetics
- Evolutionary Biology
Background:
- Wolbachia bacteria are known to form mutualistic symbioses with some Drosophila melanogaster stocks, improving host fitness.
- However, the longevity benefits of Wolbachia infection vary across different Drosophila genotypes, despite consistent infection by the same bacterial strain.
Purpose of the Study:
- To investigate the inheritance of the survival phenotype associated with Wolbachia infection in Drosophila.
- To determine the dependence of this phenotype on host genotype, sex, and mating conditions.
Main Methods:
- Reciprocal hybrid crosses between two Drosophila melanogaster strains (Z53 and Z2) with differing responses to Wolbachia.
- Comparison of Wolbachia effects on survival in single-sex cages versus mixed-sex mating cages.
Main Results:
- Positive Wolbachia effects on survival were more pronounced in hybrid flies than in parental lines, challenging exclusive maternal inheritance.
- Survival benefits were significantly higher in single-sex cages, indicating a strong influence of mating conditions.
- Wolbachia infection appeared to increase the cost of reproduction, particularly in males, with survival effects comparable to reproduction's negative impact.
Conclusions:
- The survival phenotype associated with Wolbachia is influenced by host genotype and environmental factors like mating conditions.
- Reproduction imposes a significant survival cost in Drosophila, which can be modulated by Wolbachia infection.
- These findings have implications for understanding insect-host-microbe interactions and the evolution of symbioses.
