Related Experiment Video
Updated: Nov 3, 2025
10:19
Screening and Identification of RNA Silencing Suppressors from Secreted Effectors of Plant Pathogens
Published on: February 3, 2020
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Viroids as a Tool to Study RNA-Directed DNA Methylation in Plants
Michael Wassenegger1,2, Athanasios Dalakouras3,4
1RLP AgroScience GmbH, 67435 Neustadt an der Weinstrasse, Germany.
Cells
|June 2, 2021
Summary
Viroids, small RNA molecules, have been instrumental in uncovering RNA-directed DNA methylation (RdDM). This review details how viroid research advanced our understanding of RdDM mechanisms and proposes an updated model.
Area of Science:
- Plant Pathology
- Molecular Biology
- Epigenetics
Background:
- Viroids are pathogenic circular ssRNAs that replicate via dsRNA intermediates.
- Viroid replication activates plant RNA interference (RNAi) pathways, including PTGS and RdDM.
- RNA-directed DNA Methylation (RdDM) can lead to Transcriptional Gene Silencing (TGS).
Purpose of the Study:
- To review the pivotal role of Pospiviroidae in the discovery of RdDM.
- To elucidate the mechanistic details of RdDM over the past three decades.
- To propose a revised RdDM model integrating viroid and non-viroid evidence.
Main Methods:
- Literature review focusing on viroid-based systems and RNAi.
- Analysis of mechanistic studies on RdDM.
- Synthesis of evidence from diverse plant systems.
Main Results:
- Pospiviroidae research was crucial for identifying and understanding RdDM.
- Viroid systems have progressively revealed intricate RdDM mechanisms.
- A comprehensive body of evidence supports a refined RdDM model.
Conclusions:
- Viroid research has significantly advanced the field of epigenetics, particularly RdDM.
- The proposed revised RdDM model offers a more integrated understanding of the process.
- This review consolidates knowledge, paving the way for future epigenetic studies.
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