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ICTV Virus Taxonomy Profile: Nanoviridae
John E Thomas1, Bruno Gronenborn2, Robert M Harding3
1QAAFI, The University of Queensland, GPO Box 267, Brisbane, Queensland 4001, Australia.
The Journal of General Virology
|January 12, 2021
Summary
The Nanoviridae family comprises plant viruses with small DNA genomes transmitted by aphids. These viruses infect diverse plants, including legumes and monocots, and require a helper factor for spread.
Area of Science:
- Plant virology
- Molecular biology
- Genomics
Background:
- Nanoviridae are plant viruses characterized by small isometric virions.
- They possess multipartite, circular, single-stranded (css) DNA genomes, with each DNA molecule separately encapsidated.
- Genomic DNA segments range from 0.9-1.1 kb, and some isolates are associated with satellite-like cssDNAs (alphasatellites).
Purpose of the Study:
- To summarize the International Committee on Taxonomy of Viruses (ICTV) report on the family Nanoviridae.
- To provide an overview of the classification, characteristics, and host range of nanovirids.
Main Methods:
- The study is a summary of the official ICTV report.
- Information is compiled from existing taxonomic and scientific literature.
Main Results:
- The family Nanoviridae includes two genera: Nanovirus (infecting eudicots, primarily legumes) and Babuvirus (infecting monocotyledons, primarily Zingiberales).
- Nanovirids require a virus-encoded helper factor for aphid transmission, which is circulative and non-propagative.
- Genomic components are distinct, with each cssDNA molecule encapsidated separately.
Conclusions:
- Nanoviridae represents a distinct family of plant viruses with unique genomic and transmission characteristics.
- Understanding nanovirid biology is crucial for managing plant diseases caused by these viruses.
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