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Pathogenesis by subviral agents: viroids and hepatitis delta virus
Ricardo Flores1, Robert A Owens2, John Taylor3
1Instituto de Biología Molecular y Celular de Plantas (UPV-CSIC), Universidad Politécnica de Valencia, Valencia 46022, Spain.
Current Opinion in Virology
|February 22, 2016
Summary
Plant viroids and human Hepatitis Delta Virus (HDV) are simple RNA pathogens. This review explores how their RNA structures and replication strategies cause disease, focusing on RNA silencing in viroid pathogenesis.
Area of Science:
- Molecular Biology
- Virology
- Genetics
Background:
- Viroids are the simplest infectious genetic elements, with small RNA genomes and no protein-coding ability.
- Hepatitis Delta Virus (HDV) is a more complex human pathogen, co-infecting with Hepatitis B Virus (HBV), possessing a larger RNA genome and limited protein expression.
- Both viroids and HDV share structural and replication similarities, including circular RNA, compact folding, and rolling-circle replication.
Purpose of the Study:
- To review the pathogenic mechanisms of viroids and HDV.
- To elucidate how these simple RNA agents cause disease by manipulating host components.
- To highlight the role of RNA silencing in viroid pathogenesis.
Main Methods:
- Review of existing literature on viroid and HDV biology and pathogenesis.
- Analysis of shared structural and replication features.
- Focus on RNA-based mechanisms, including RNA silencing.
Main Results:
- Viroid and HDV simplicity necessitates extensive reliance on host machinery for replication.
- This reliance on host components directly and indirectly leads to pathogenic effects.
- RNA silencing is identified as a key mediator in certain aspects of viroid pathogenesis.
Conclusions:
- The pathogenesis of viroids and HDV is intrinsically linked to their simple RNA nature and reliance on host factors.
- Understanding these mechanisms is crucial for developing antiviral strategies.
- RNA silencing plays a significant role in the disease-causing processes of viroids.
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