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Updated: Jul 16, 2026
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Rearing and Double-stranded RNA-mediated Gene Knockdown in the Hide Beetle, Dermestes maculatus
Published on: December 28, 2016
Structure of Dicer and mechanistic implications for RNAi
I J Macrae1, F Li, K Zhou
1Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720, USA.
Cold Spring Harbor Symposia on Quantitative Biology
|March 27, 2007
Summary
Dicer enzymes, crucial for RNA interference (RNAi), possess flexible structures enabling double-stranded RNA (dsRNA) binding and processing. This study models Dicer
Area of Science:
- Molecular Biology
- Biochemistry
- Structural Biology
Background:
- Dicer is a ribonuclease essential for RNA interference (RNAi) by processing double-stranded RNA (dsRNA) into small RNA fragments.
- Previous work established the crystal structure of Giardia intestinalis Dicer, providing a basis for understanding dsRNA processing.
Purpose of the Study:
- To investigate the structural dynamics of Dicer enzymes and their role in dsRNA binding and processing.
- To explore the function of accessory domains present in higher eukaryotic Dicers but absent in Giardia Dicer.
- To propose a model for the RNA-induced silencing complex (RISC)-loading complex architecture.
Main Methods:
- Structural analysis of Dicer enzymes.
- Biochemical data integration.
- Comparative analysis of Dicer domains.
Main Results:
- Evidence suggests Dicer comprises three rigid regions linked by flexible hinges, facilitating dsRNA interaction.
- Conformational flexibility is proposed to be key for efficient dsRNA binding and processing.
- The study examines accessory domains in higher eukaryotic Dicers.
Conclusions:
- Dicer's flexible, multi-domain structure is critical for its function in RNA interference.
- A refined model for the RISC-loading complex architecture is proposed, integrating structural and biochemical findings.
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