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Updated: Jun 13, 2026
10:55
Vaccinia Virus Infection & Temporal Analysis of Virus Gene Expression: Part 2
Published on: April 10, 2009
[Study of coding sequences of variable regions in smallpox virus genome]
Voprosy Virusologii
|May 12, 2010
Summary
This study analyzed variola virus (VARV) open reading frames (ORFs), revealing unique genes and evolutionary patterns. VARV ORF C3L shows adaptive selection, suggesting a key role in human VARV adaptation.
Area of Science:
- Virology
- Genomics
- Molecular Biology
Context:
- The variola virus (VARV) genome contains variable regions with potential open reading frames (ORFs).
- Comparative analysis of ORFs across different VARV strains and orthopoxviruses is crucial for understanding viral evolution and adaptation.
Purpose:
- To identify and characterize potential ORFs in the terminal variable regions of the variola virus genome.
- To conduct a detailed structural and functional analysis of these ORFs and compare them with homologous ORFs in other orthopoxviruses.
- To detect conserved and variable ORFs across 70 VARV strains and identify unique genetic features.
Summary:
- Analysis revealed conserved and heterogeneous ORFs among 70 VARV strains, including a unique 111 amino acid ORF in the Helder and Mary strains.
- The D14L ORF was found to be disintegrated into two separate ORFs exclusively in the Helder strain, and database ambiguities for VARV ORFs were noted.
- The predominant evolutionary force identified was stabilizing selection, with the exception of VARV ORF C3L, which exhibits adaptive selection.
Impact:
- Identified a unique ORF in specific VARV strains and clarified ambiguities in existing databases.
- Established that VARV ORF C3L is under adaptive selection, unlike its orthopoxviral counterparts.
- Suggests that VARV ORF C3L plays a significant role in the adaptation of variola virus to human hosts.
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