Advanced Review
Viroids: self-replicating, mobile, and fast-evolving noncoding regulatory RNAs
Biao Ding,
Corresponding Author
Biao Ding
Department of Plant Cellular and Molecular Biology and Plant Biotechnology Center, The Center for RNA Biology, and Molecular, Cellular and Developmental Biology Program, The Ohio State University, 207 Rightmire Hall, 1060 Carmack Road, Columbus, OH 43210, USA
Department of Plant Cellular and Molecular Biology and Plant Biotechnology Center, The Center for RNA Biology, and Molecular, Cellular and Developmental Biology Program, The Ohio State University, 207 Rightmire Hall, 1060 Carmack Road, Columbus, OH 43210, USASearch for more papers by this author
Biao Ding,
Corresponding Author
Biao Ding
Department of Plant Cellular and Molecular Biology and Plant Biotechnology Center, The Center for RNA Biology, and Molecular, Cellular and Developmental Biology Program, The Ohio State University, 207 Rightmire Hall, 1060 Carmack Road, Columbus, OH 43210, USA
Department of Plant Cellular and Molecular Biology and Plant Biotechnology Center, The Center for RNA Biology, and Molecular, Cellular and Developmental Biology Program, The Ohio State University, 207 Rightmire Hall, 1060 Carmack Road, Columbus, OH 43210, USASearch for more papers by this authorAbstract
Viroids are small, circular, and noncoding RNAs that infect plants. They replicate in the nucleus or chloroplast and then traffic from cell to cell and from organ to organ to establish systemic infection. Viroids achieve nearly all of the biological functions by directly interacting with host cellular factors. Viroid replication, together with replication of human hepatitis delta virus, demonstrates the biological novelty and significance of RNA-dependent RNA polymerase activities of DNA-dependent RNA polymerases. Viroid systemic infection uncovers a new biological principle—the role of three-dimensional RNA structural motifs mediating RNA trafficking between specific cells. Viroid diseases are virtually the consequences of host gene regulation by noncoding RNAs. A viroid RNA has the highest in vivo mutation rate among all known nucleic acid replicons. The host range of many viroids is expanding, essentially as a result of continuing and fast evolution of noncoding sequences/structures to gain new biological functions. Here, I discuss recent progress in these areas, emphasizing the broad significance of viroid research to the discovery of fundamental biological principles. Copyright © 2010 John Wiley & Sons, Ltd.
This article is categorized under:
- Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs
- RNA in Disease and Development > RNA in Disease
- RNA in Disease and Development > RNA in Development
FURTHER READING
- Diener TO. Discovering viroids—a personal perspective. Nature Rev Microbiol 2003, 1: 75–80.
- Ding B, Zhong X. Viroids/Virusoids. In: M Schaechter, ed. Encyclopedia of Microbiology. 3rd ed. Amsterdam: Elsevier Science; 2009, 535–545.
10.1016/B978-012373944-5.00322-9 Google Scholar
- Hadidi A, Flores R, Randles JW, Semancik JS, eds. Viroids. Collingwood: CSIRO Publishing; 2003.
RELATED WIREs ARTICLE
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