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Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
Published on: August 18, 2010
A micrococcal nuclease homologue in RNAi effector complexes
Amy A Caudy1, René F Ketting, Scott M Hammond
1Cold Spring Harbor Laboratory, Watson School of Biological Sciences, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA.
Nature
|September 26, 2003
Summary
Tudor-SN protein is a key component of the RNA-induced silencing complex (RISC) across species. This finding identifies a novel nuclease domain within RISC, potentially explaining RNA degradation in RNA interference (RNAi).
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- RNA interference (RNAi) is a biological process that regulates gene expression.
- RNAi effects are mediated by the RNA-induced silencing complex (RISC).
- Previous studies identified four Drosophila RISC components involved in mRNA degradation.
Purpose of the Study:
- To identify novel components of the RISC enzyme.
- To investigate the role of Tudor-SN in RNA interference.
- To characterize the enzymatic activity of Tudor-SN.
Main Methods:
- Protein identification and purification.
- Nuclease activity assays.
- Enzyme inhibition studies.
Main Results:
- Tudor-SN was identified as a component of RISC in Caenorhabditis elegans, Drosophila, and mammals.
- Purified Tudor-SN exhibited nuclease activity comparable to staphylococcal nucleases.
- Both purified Tudor-SN and RISC were inhibited by a micrococcal nuclease inhibitor.
Conclusions:
- Tudor-SN is the first identified RISC subunit with a recognizable nuclease domain.
- Tudor-SN likely contributes to the RNA degradation observed in RNAi.
- This discovery provides new insights into the mechanism of RNA interference.
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