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09:05
MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
Gene copy number is differentially regulated in a multipartite virus
Anne Sicard1, Michel Yvon, Tatiana Timchenko
1INRA, UMR BGPI INRA-CIRAD-SupAgro, Cirad TA-A54/K, Campus International de Baillarguet, 34398 Montpellier, France.
Nature Communications
|August 6, 2013
Summary
Multipartite viruses face challenges with segment frequency. This study reveals differential gene copy number control in plant nanoviruses, impacting infection and symptoms, offering a potential benefit for these complex viruses.
Area of Science:
- Virology
- Molecular Biology
- Plant Pathology
Background:
- Multipartite viruses possess segmented genomes, with each segment encapsidated separately.
- A key challenge for these viruses is ensuring all segments are present for successful infection, especially if segment frequencies vary.
Purpose of the Study:
- To investigate the cost associated with segment frequency in multipartite viruses.
- To analyze the impact of viral gene copy number variation on viral accumulation and symptom development in plant nanoviruses.
Main Methods:
- Monitoring the copy number of eight single-gene segments in a plant nanovirus genome.
- Assessing the relationship between viral gene frequency, viral accumulation, and symptom expression across different host plants.
Main Results:
- Significant variation in viral gene frequencies was observed, with some segments accumulating at low levels and others dominating.
- The relative frequency of viral genes directly influenced viral accumulation and symptom severity.
- These frequency dynamics were host-specific, indicating adaptive responses.
Conclusions:
- The differential control of gene/segment copy number is a crucial factor in multipartite virus biology.
- This regulatory mechanism may provide an adaptive advantage, potentially offsetting the costs associated with rare segments.
- Findings challenge existing theories on the benefits of viral genome segmentation.
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