Published online 30 March 2005
Methods Online |
L1 retrotransposon-mediated stable gene silencing
Department of Genetics, University of Pennsylvania Philadelphia, PA 19104, USA 1Center for Research on Reproduction and Women's Health and Abramson Family Cancer Research Institute, University of Pennsylvania Philadelphia, PA 19104, USA
*To whom correspondence should be addressed. Tel: +1 215 898 3582; Fax: +1 215 573 7760; Email: kazazian{at}mail.med.upenn.edu
Received September 26, 2004. Revised January 4, 2005. Accepted March 7, 2005.
RNA interference (RNAi) is widely used for functional studies and has been proposed as a potential therapeutic agent. Current RNAi systems are largely efficient, but have limitations including transient effect, the need for viral handling and potential insertional mutations. Here, we describe a simple L1 retrotransposon-based system for the delivery of small interfering RNA (siRNA) and stable silencing in human cells. This system demonstrated long-term siRNA expression and significant reduction in both exogenous and endogenous gene expression by up to 90%. Further characterization indicated that retrotransposition occurred in a controlled manner such that essentially only one RNAi-cassette was integrated into the host genome and was sufficient for strong interference. Our system provides a novel strategy for stable gene silencing that is easy and efficient, and it may have potential applications for ex vivo and in vivo molecular therapy.