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Vaccinia Virus Infection & Temporal Analysis of Virus Gene Expression: Part 2
Published on: April 10, 2009
Virus adaptation by manipulation of host's gene expression
Patricia Agudelo-Romero1, Pablo Carbonell, Miguel A Perez-Amador
1Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-UPV, València, Spain.
Plos One
|June 12, 2008
Summary
Plant viruses can evolve to infect new hosts by acquiring mutations. This study shows an evolved virus escaped host defenses and altered gene expression, highlighting viral adaptation strategies.
Area of Science:
- Virology
- Evolutionary Biology
- Molecular Biology
Background:
- Viruses adapt to hosts by evading defenses and manipulating cellular metabolism.
- Cross-species viral transmission can lead to emerging viruses if beneficial mutations arise.
- Viral evolution experiments provide insights into host-pathogen dynamics.
Purpose of the Study:
- To investigate the evolutionary trajectory of a plant virus in a novel host.
- To identify genetic changes and their impact on viral virulence and host gene expression.
- To understand viral adaptation mechanisms, including host defense evasion.
Main Methods:
- Serial passage of a plant virus in a naive host over 17 generations.
- Whole-genome sequencing to identify viral mutations.
- DNA microarray analysis to assess host gene expression changes.
- Analysis of viral protein substitutions (VPg and P3) and their effects.
Main Results:
- The viral genome accumulated five mutations, three non-synonymous, after 17 passages.
- An amino acid substitution in VPg caused symptom appearance.
- A substitution in P3 epistasis exacerbated disease severity.
- Evolved and ancestral viruses differentially impacted host gene expression.
- Genes involved in stress and pathogen response were not activated by the evolved virus.
Conclusions:
- Viral evolution in a new host involved acquiring mutations that alter virulence and host interactions.
- The evolved virus demonstrated an enhanced ability to evade host defenses.
- Specific viral protein changes are critical for adaptation and disease manifestation.
- Understanding these evolutionary dynamics is key to predicting and managing emerging viral threats.
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