Viral Packaging For Wasp Eggs

Parasitic wasps called Venturia canescens lay their eggs in caterpillars, but not before coating the eggs with protective liposomes. The liposomes contain a battery of protein weapons that help the wasp progeny combat the immune system of the caterpillar, which certainly doesn’t want to be a wasp incubator. Researchers have long thought the liposomes resemble viral containers and referred to them as “virus-like-particles.” Now there’s proof of the liposome’s viral provenance (Sci. Adv. 2015, DOI: 10.1126/sciadv.1501150). A team of researchers led by Jean-Michel Drezen of François Rabelais de Tours University and Anne-Nathalie Volkoff of the University of Montpellier report that the genes for making the liposome machinery found in the wasp genome correspond to nudivirus DNA. They propose that a few million years ago, nudiviruses infected the wasp and inserted their DNA into the wasp genome. In the intervening years, the wasp evolved a way to repurpose the viral DNA—particularly the virus’ liposomal packaging—for its own infective, reproductive purposes. The researchers propose that the work could help humans develop ways to use viral liposomes to deliver drugs—instead of baby bugs.