With a little help from my friends: complementation as a survival strategy for viruses in a long-lived host system

Virology. 2015 Apr;478:123-8. doi: 10.1016/j.virol.2014.12.041. Epub 2015 Feb 7.


In selective host species, the extent of Citrus tristeza virus (CTV) infection is limited through the prevention of long-distance movement. As CTV infections often contain a population of multiple strains, we investigated whether the members of a population were capable of interaction, and what effect this would have on the infection process. We found that the tissue-tropism limitations of strain T36 in selective hosts could be overcome through interaction with a second strain, VT, increasing titer of, and number of cells infected by, T36. This interaction was strain-specific: other strains, T30 and T68, did not complement T36, indicating a requirement for compatibility between gene-products of the strains involved. This interaction was also host-specific, suggesting a second requirement of compatibility between the provided gene-product and host. These findings provide insight into the 'rules' that govern interaction between strains, and suggest an important mechanism by which viruses survive in a changing environment.

Keywords: Citrus tristeza virus; Complementation; Movement; Phloem; Population.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Closterovirus / genetics
  • Closterovirus / physiology*
  • Host Specificity
  • Host-Pathogen Interactions
  • Microbial Interactions*
  • Plant Diseases / virology
  • Viral Load
  • Viral Tropism*