A retrovirus-based system to stably silence hepatitis B virus genes by RNA interference.

School of Life Sciences, Sichuan University, Chengdu , 610064, China.
Biotechnology Letters (Impact Factor: 1.74). 11/2006; 28(20):1679-85. DOI: 10.1007/s10529-006-9138-z
Source: PubMed

ABSTRACT RNA interference (RNAi) might be an efficient antiviral therapy for some obstinate illness. Herein, a retrovirus-based RNAi system was developed to drive expression and delivery of Hepatitis B virus (HBV)-specific short hairpin RNA (shRNA) in HepG2 cells. The levels of HBsAg and HBeAg and that of HBV mRNA were dramatically decreased by this RNAi system in HepG2 cells transfected with Topo-HBV plasmid. Retrovirus-based RNAi thus may be useful for therapy in HBV and other viral infections and provide new clues for prophylactic vaccine development.

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    ABSTRACT: RNA interference (RNAi) is a RNA dependent gene silencing mechanism which includes endogenously induced gene silencing effects of miRNA as well as silencing triggered by foreign dsRNA. The dsRNA binds with a protein complex DICER which cleaves it into short fragments with a few unpaired overhung bases at both ends. The short dsRNA fragments (SiRNA) or miRNA integrate with another active protein complex RISC. Consequently, one of the RNA strands (anti-guide strand) is degraded while the other is selected as a guide strand which remains bound to RISC complex. When a complementary mRNA is located by an RISC bound guide strand, it binds to it and is cleaved and degraded. The RNAi offers a new technology in healthcare and crop improvement.