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07:06
Principles of Site-Specific Recombinase (SSR) Technology
Published on: May 29, 2008
Control of siRNA expression utilizing Cre-loxP recombination system
Vivi Kasim1, Makoto Miyagishi, Kazunari Taira
1Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Hongo, Tokyo 113-8656, Japan.
Nucleic Acids Research. Supplement (2001)
|September 27, 2003
Summary
Researchers developed a controllable RNA interference (RNAi) system using the Cre-loxP system for specific siRNA expression in mammalian cells. This "Cre-On" vector enables inducible siRNA generation, effectively suppressing reporter gene activity upon Cre recombinase addition.
Area of Science:
- Molecular Biology
- Gene Regulation
Background:
- RNA interference (RNAi) utilizes small interfering RNA (siRNA) for gene silencing.
- Pol III promoters enable high-level transcription of siRNA expression vectors in mammalian cells.
- Controlling siRNA expression is crucial for precise gene silencing applications.
Purpose of the Study:
- To develop a controllable siRNA expression system in mammalian cells.
- To investigate the efficacy of the Cre-loxP system for inducible siRNA expression.
- To validate the functionality of a "Cre-On" siRNA vector using firefly luciferase as a reporter.
Main Methods:
- Construction of a "Cre-On" siRNA expression vector regulated by the U6 promoter.
- Utilizing the Cre-loxP recombination system for inducible gene expression.
- Delivery of Cre recombinase via a TAT-NLS-Cre fusion protein into cells.
- Assessment of siRNA-mediated gene silencing by measuring firefly luciferase activity.
Main Results:
- The "Cre-On" siRNA vector demonstrated Cre-dependent, inducible siRNA expression.
- Addition of TAT-NLS-Cre protein successfully triggered siRNA generation.
- Significant suppression of firefly luciferase activity was observed upon TAT-NLS-Cre treatment.
- The system allows for precise control over siRNA expression and subsequent gene silencing.
Conclusions:
- The Cre-loxP system provides effective temporal control over pol III promoter-driven siRNA expression.
- The developed "Cre-On" vector system is a valuable tool for inducible RNA interference in mammalian cells.
- This controllable system enhances the utility of RNAi for research and potential therapeutic applications.
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