[The great virus comeback].
1Université Paris-Sud, Institut de Génétique Microbiologie, CNRS UMR 8621, 91405 Orsay Cedex, France - Institut Pasteur, 25 rue du Dr Roux, 75015 Paris, France.
Biologie Aujourd'Hui
|December 17, 2013
Summary
Viruses are abundant and diverse, challenging their view as evolutionary byproducts. Recent discoveries reveal viruses as ancient, polyphyletic entities that significantly drive cellular evolution and biological diversity.
Area of Science:
- Virology and Evolutionary Biology
- Genomics and Bioinformatics
- Microbiology and Astrobiology
Context:
- Traditional view of viruses as simple evolutionary byproducts is outdated.
- Viral particles are the most abundant biological entities globally.
- Metagenomic and comparative genomic analyses reveal extensive viral gene diversity.
Purpose:
- To redefine viruses based on recent discoveries in viral ecology, genomics, and structural biology.
- To explore the ancient origins and polyphyletic nature of viruses.
- To elucidate the role of viruses in cellular evolution and the origin of life.
Summary:
- Viruses are ancient, diverse, and polyphyletic, originating before the Last Universal Common Ancestor (LUCA).
- The virocell concept defines viruses as living organisms that transform host cells, driving viral genome replication, evolution, and function transfer.
- Viruses are crucial engines of biological evolution, contributing to major evolutionary transitions and acting as primary sources of variation and selection.
Impact:
- Challenges the traditional view of viruses, highlighting their fundamental role in life's evolution.
- Provides a new framework (virocell concept) for understanding virus-host interactions and viral life cycles.
- Underscores viruses as major drivers of biodiversity and evolutionary innovation.
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