The phage gene wmk is a candidate for male killing by a bacterial endosymbiont

Area of Science:

• Microbiology
• Genetics
• Evolutionary Biology

Background:

• Wolbachia are widespread bacteria influencing arthropod evolution and physiology.
• Parasitic drive systems, like male killing, enhance the fitness of infected females, facilitating Wolbachia spread.
• The genetic basis for Wolbachia-induced male killing has remained elusive despite extensive research.

Purpose of the Study:

• To identify the specific gene(s) responsible for Wolbachia-induced male killing.
• To investigate the molecular mechanisms underlying this sex-specific lethality.

Main Methods:

• Comparative genomics was employed to analyze Wolbachia prophage WO.
• Transgenic approaches were used to test candidate genes.
• Cytological analyses were performed to observe developmental defects.

Main Results:

• A candidate gene, WO-mediated killing (wmk), was identified within the Wolbachia prophage WO.
• Transgenic expression of wmk induced male-specific lethality during early fruit fly embryogenesis.
• Cytological defects consistent with male killing pathology were observed.

Conclusions:

• The discovery of wmk provides a genetic basis for Wolbachia-induced male killing.
• This finding suggests a potential role for phage genes in causing sex-specific lethality.
• Wmk offers new avenues for exploring arthropod pest and vector control strategies.