Apparent replication of an unusual virus-like particle in both a parasitoid wasp and its host

Area of Science:

• Entomology
• Virology
• Parasitology

Background:

• Tussock moth larvae infected by the braconid wasp Apanteles melanoscelus exhibit unique nuclear inclusion bodies.
• These bodies are hypothesized to be sites of replication for an unusual virus-like particle.

Purpose of the Study:

• To investigate the nature and origin of nuclear inclusion bodies in parasitized tussock moth larvae.
• To determine the relationship between these bodies, virus-like particles, and the parasitoid wasp.

Main Methods:

• Microscopic examination of hemocytes from parasitized tussock moth larvae.
• Observation of calyx cells within the parasitoid wasp Apanteles melanoscelus.

Main Results:

• Nuclear inclusion bodies were consistently found in the hemocytes of all parasitized tussock moth larvae.
• Identical virus-like particles were observed within the nuclei of a subset of parasitoid calyx cells.
• These particles are presumed to be transmitted from the wasp to the host during egg-laying.

Conclusions:

• Nuclear inclusion bodies in tussock moth larvae are associated with the replication of a specific virus-like particle.
• The virus-like particle originates from the parasitoid wasp Apanteles melanoscelus.
• Transmission likely occurs during the oviposition process, impacting host larvae.