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Updated: May 15, 2026
10:39
In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection
Published on: November 27, 2014
A detailed comparative analysis on the overall codon usage patterns in West Nile virus.
Gonzalo Moratorio1, Andrés Iriarte, Pilar Moreno
1Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay.
Summary
West Nile virus (WNV) codon usage shows slight genomic bias, influenced by dinucleotide frequencies. This viral evolution is shaped by genome composition, antiviral evasion, and adaptation to diverse host environments.
Area of Science:
- Virology
- Genomics
- Evolutionary Biology
Background:
- West Nile virus (WNV), a Flaviviridae family member, cycles between mosquitoes and birds, infecting humans and horses as dead-end hosts.
- Understanding codon usage bias is crucial for comprehending viral evolution and host-pathogen interactions.
- Complete genome sequences of 449 WNV strains provide a robust dataset for comprehensive analysis.
Purpose of the Study:
- To conduct a comprehensive analysis of codon usage bias across numerous West Nile virus strains.
- To investigate the factors influencing codon usage patterns in WNV, including host species and genomic composition.
- To elucidate the evolutionary mechanisms driving WNV codon usage.
Main Methods:
- Analysis of complete genome sequences from 449 West Nile virus strains.
- Calculation of the Effective Number of Codons (ENC) to assess overall codon usage bias.
- Comparison of Codon Adaptation Index (CAI) values between WNV genes and human genes.
- Examination of relative synonymous codon usage (RSCU) in WNV strains from different hosts and its correlation with dinucleotide frequencies.
Main Results:
- Overall codon usage bias in WNV strains is minimal, as indicated by ENC values.
- Codon Adaptation Index (CAI) values for WNV genes differ significantly from those of human genes.
- Relative synonymous codon usage patterns are similar across WNV strains from birds, equines, humans, and mosquitoes.
- Dinucleotide frequencies significantly influence the relative synonymous codon usage in WNV.
Conclusions:
- WNV genomic biases result from a combination of evolutionary genome composition, adaptation to evade host antiviral responses, and mutation-selection dynamics.
- The virus dynamically re-adapts its codon usage to suit various environmental and host contexts.
- These findings contribute to a deeper understanding of WNV evolution and adaptation strategies.
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