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Updated: May 25, 2026
10:53
Isolation of Cognate RNA-protein Complexes from Cells Using Oligonucleotide-directed Elution
Published on: January 16, 2017
Coenzymes, viruses and the RNA world
Fabián Reyes-Prieto1, Ricardo Hernández-Morales, Rodrigo Jácome
1Facultad de Ciencias, UNAM, Apdo. Postal 70-407, Cd. Universitaria, 04510 México D.F., Mexico.
Biochimie
|January 25, 2012
Summary
RNA viruses do not appear to encode coenzyme biosynthesis genes, challenging their role as relics of an RNA/protein world. DNA viruses possess some genes, but not complete pathways, suggesting early life may have used fragmented RNA systems.
Area of Science:
- Virology
- Bioinformatics
- Molecular Evolution
Background:
- Understanding viral origins and metabolic capabilities is crucial for evolutionary studies.
- Ribonucleotidyl coenzymes are essential for numerous biochemical reactions.
- Previous research has explored viral gene content, but comprehensive analysis of coenzyme biosynthesis pathways is limited.
Purpose of the Study:
- To conduct a detailed bioinformatic search for ribonucleotidyl coenzyme biosynthetic sequences in viral genomes.
- To investigate the presence and completeness of coenzyme biosynthesis pathways in RNA and DNA viruses.
- To assess the implications of these findings for theories on the origin of viruses and early life.
Main Methods:
- Bioinformatic analysis of viral genome sequences available up to April 2011.
- Sequence homology searches for genes involved in ribonucleotidyl coenzyme biosynthesis.
- Comparative genomics of DNA and RNA viral families.
Main Results:
- No RNA viral genomes examined encode sequences for coenzyme biosynthesis.
- DNA viruses (single- and double-stranded) contain a variety of coenzyme biosynthetic genes, but no complete pathways were identified.
- Findings suggest RNA viruses are unlikely to be direct descendants of an ancient RNA/protein world.
Conclusions:
- The absence of coenzyme biosynthesis genes in RNA viruses challenges their direct lineage from an RNA/protein world.
- The partial presence of these genes in DNA viruses indicates some metabolic gene acquisition but not complete pathway reconstruction.
- Early life forms preceding DNA genomes might have relied on discontinuous genetic systems composed of multiple small RNA sequences.
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