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Published on: September 26, 2011
Retroviral diversity and distribution in vertebrates
E Herniou1, J Martin, K Miller
1Department of Biology, Imperial College, Ascot, Berkshire SL5 7PY, United Kingdom.
Journal of Virology
|June 17, 1998
Summary
Retroviruses are widespread in vertebrate genomes, with novel sequences found across diverse species. Phylogenetic analysis reveals specific retroviral groups are common, while others appear limited to mammals and birds.
Area of Science:
- Virology
- Genomics
- Evolutionary Biology
Background:
- Endogenous retroviruses (ERVs) are integrated into host genomes.
- Understanding ERV diversity across vertebrate classes is crucial for evolutionary insights.
Purpose of the Study:
- To screen for and characterize novel endogenous retroviruses in diverse vertebrate hosts.
- To investigate the distribution and evolutionary relationships of ERVs across vertebrate classes.
Main Methods:
- Polymerase chain reaction (PCR) screening of 18 vertebrate orders.
- Sequencing of protease and reverse transcriptase genes (approx. 1 kb) for novel retroviral isolates.
- Phylogenetic analysis to determine viral relationships.
Main Results:
- Thirty novel retroviral sequences were identified in reptilian, amphibian, and piscine hosts.
- Spumavirus- and murine leukemia virus-like ERVs are abundant and widespread in vertebrate genomes.
- Other recognized retroviral genera were primarily found in mammals and birds, with limited cross-class transmission suggested.
Conclusions:
- Endogenous retroviruses are likely ubiquitous across most vertebrate classes, exhibiting significant diversity.
- Phylogenetic patterns suggest infrequent horizontal transmission of certain ERVs between vertebrate classes.
- Many identified sequences may represent novel retroviral genera, expanding our understanding of retroviral evolution.
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