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Evolution: the long evolutionary reach of viruses
1Department of Biological Sciences, Pittsburgh Bacteriophage Institute, University of Pittsburgh, Pittsburgh 15260, USA. rhx@vms.cis.pitt.edu
Current Biology : CB
|December 23, 1999
Summary
Viral capsid protein structures suggest shared ancestry between phages and animal viruses. This implies ancient viral lineages or extensive cross-domain viral gene transfer.
Area of Science:
- Virology
- Molecular Biology
- Evolutionary Biology
Background:
- The evolutionary origins of viruses remain a complex and debated topic.
- Understanding viral ancestry is crucial for deciphering early life evolution.
Purpose of the Study:
- To investigate the evolutionary relationship between bacteriophages and animal viruses.
- To explore hypotheses regarding the origins of viral lineages in relation to the domains of life.
Main Methods:
- Comparative analysis of phage capsid protein structures.
- Phylogenetic analysis to infer evolutionary relationships.
Main Results:
- Structural similarities were identified between a specific phage capsid protein and those found in animal viruses.
- This structural evidence suggests a shared evolutionary history.
Conclusions:
- The findings support the hypothesis that viral lineages may predate the three domains of life (Bacteria, Archaea, Eukarya).
- Alternatively, viruses may have evolved mechanisms for extensive horizontal gene transfer across these major phylogenetic domains.
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