The dual lifestyle of genome-integrating virophages in protists

Ann N Y Acad Sci. 2019 Jul;1447(1):97-109. doi: 10.1111/nyas.14118. Epub 2019 Jun 4.

Abstract

DNA viruses with efficient host genome integration capability were unknown in eukaryotes until recently. The discovery of virophages, satellite-like DNA viruses that depend on lytic giant viruses that infect protists, revealed a genetically diverse group of viruses with high genome mobility. Virophages can act as strong inhibitors of their associated giant viruses, and the resulting beneficial effects on their unicellular hosts resemble a population-based antiviral defense mechanism. By comparing various aspects of genome-integrating virophages, in particular the virophage mavirus, with other mobile genetic elements and parasite-derived defense mechanisms in eukaryotes and prokaryotes, we show that virophages share many features with other host-parasite systems. Yet, the dual lifestyle exhibited by mavirus remains unprecedented among eukaryotic DNA viruses, with potentially far-reaching ecological and evolutionary consequences for the host.

Keywords: genome integration; host-parasite interaction; protist; virophage; virus.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Genome, Viral / physiology*
  • Host-Parasite Interactions / physiology*
  • Humans
  • Virophages / genetics*
  • Virophages / metabolism*