Transcriptomic analysis of oriental tea tortrix infected with male-killing virus

Area of Science:

• Entomology
• Virology
• Molecular Biology

Background:

• Male-killing is a reproductive manipulation where males die during development.
• While often caused by bacteria, symbiotic viruses can also induce male lethality.
• Osugoroshi virus 1-3 (OGVs) in the moth Homona magnanima cause male-killing via molting arrest.

Purpose of the Study:

• To investigate the molecular mechanisms of OGV-induced male mortality.
• To elucidate transcriptional and endocrine changes in OGV-infected male moths.

Main Methods:

• Comparative RNA sequencing of OGV-infected and uninfected male larvae at different developmental stages.
• KEGG pathway enrichment analysis to identify differentially expressed genes.
• Liquid chromatography-tandem mass spectrometry to analyze hormone levels (20-hydroxyecdysone).

Main Results:

• Male-specific upregulation of Toll/Imd and EGF receptor signaling pathways observed.
• Downregulation of metabolism-related genes in infected males.
• Persistent 20-hydroxyecdysone (20E) detected in arrested males, unlike in normal males; ecdysone oxidase expression remained unchanged.

Conclusions:

• OGV infection triggers male-specific transcriptional reprogramming and endocrine disruption.
• Delayed 20E clearance is linked to molting arrest.
• Unchanged ecdysone oxidase suggests complex regulatory mechanisms in virus-induced male-killing.