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Updated: May 10, 2026
06:48
A Reporter Assay to Analyze Intronic microRNA Maturation in Mammalian Cells
Published on: June 16, 2022
Regulation of RNA interference by Hsp90 is an evolutionarily conserved process
Yang Wang1, Rebecca Mercier1, Tom C Hobman2
1Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Canada.
Biochimica Et Biophysica Acta
|July 6, 2013
Summary
Introducing specific yeast and human proteins can restore RNA interference (RNAi) in yeast. Heat shock protein 90 (Hsp90) also regulates these RNAi components, suggesting its ancient role.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- RNA interference (RNAi) is a crucial gene regulation mechanism found in most eukaryotes, but notably absent in Saccharomyces cerevisiae.
- Previous research indicated that introducing Argonaute and Dicer from Saccharomyces castellii could re-establish RNAi in S. cerevisiae.
Purpose of the Study:
- To investigate the minimal components required for reconstituting a functional RNAi system in yeast.
- To determine the role of human Dicer and Argonaute2 in yeast RNAi.
- To explore the influence of Heat Shock Protein 90 (Hsp90) on Argonaute activity in yeast.
Main Methods:
- Reconstitution of RNAi in Saccharomyces cerevisiae by introducing specific genes from Saccharomyces castellii and humans.
- Co-expression of RNAi precursors with introduced proteins.
- Assessing the functional activity of RNAi machinery components.
Main Results:
- A functional RNAi system was reconstituted in yeast using only Saccharomyces castellii Dicer and human Argonaute2.
- Human Dicer, even with TRBP2, failed to restore RNAi with either S. castellii or human Argonaute.
- Human Dicer, TRBP2, and Argonaute2 were insufficient to reconstitute RNAi in yeast.
- Heat Shock Protein 90 (Hsp90) was found to regulate the activity of both human and S. castellii Argonaute in S. cerevisiae.
Conclusions:
- The combination of S. castellii Dicer and human Argonaute2 is sufficient to reconstitute RNAi in yeast.
- Human Dicer is not a functional substitute for yeast Dicer in this reconstituted system.
- Hsp90 regulation of Argonaute activity appears to be an ancient feature, potentially co-evolving with RNAi.
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