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.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Hand in hand with the availability of full genome sequences for eukaryotic model organisms and humans the demand for analysis of gene function on a system level grew. In a process called RNA interference (RNAi) specific mRNA species can be degraded by introduction of exogenous short inhibitory oligoribonucleotides (siRNAs) that are complementary to the targeted transcript sequence. This enables the selective impairment of single gene functions. During the past decade RNAi has been exploited in many different eukaryotic cell types and model organisms. Large-scale and eventually genome-wide RNAi screens ablating gene functions in a systematic manner have delivered an overwhelming amount of data on the requirement of distinct gene products for major cellular pathways. A large part of the RNAi field is dedicated to disease states such as cancer or infection with the prospect of discovering pathways suitable for new therapeutic interventions. Here some of the major steps in the development of the RNAi technology will be outlined and exemplified with a focus on the progress made in the field of mammalian host-pathogen interactions.
    New Biotechnology 02/2013; DOI:10.1016/j.nbt.2013.01.008 · 2.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: As a highly efficient delivery system, lentiviral vectors (LVs) have become a powerful tool to assess the antiviral efficacy of RNA drugs such as short hairpin RNA (shRNA) and decoys. Furthermore, recent advanced systems allow controlled expression of the effector RNA via coexpression of a tetracycline/doxycycline (DOX) responsive repressor (tTR-KRAB). Herein, this system was utilized to assess the antiviral effects of LV-encoded shRNAs targeting three conserved regions on the pregenomic RNA of hepatitis B virus (HBV), namely the region coding for the reverse transcriptase (RT) domain of the viral polymerase (LV-HBV-shRNA1), the core promoter (CP; LV-HBV-shRNA2), and the direct repeat 1 (DR1; LV-HBV-shRNA3). Transduction of just the LV-HBV-shRNA vectors into the stably HBV expressing HepG2.2.15 cell line showed significant reductions in secreted HBsAg and HBeAg, intracellular HBcAg as well as HBV RNA and DNA replicative intermediates for all vectors, however, most pronouncedly for the DR1-targeting shRNA3. The corresponding vector was therefore applied in the DOX-controlled system. Notably, strong interference with HBV replication was found in the presence of the inducer DOX whereas the antiviral effect was essentially ablated in its absence; hence, the silencing effect of the shRNA and consequently HBV replication could be strictly regulated by DOX. This newly established system may therefore provide a valuable platform to study the antiviral efficacy of RNA drugs against HBV in a regulated manner, and even be applicable in vivo.
    Virus Genes 02/2013; 46(3). DOI:10.1007/s11262-013-0886-2 · 1.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Understanding the links between resource dependence and socio-economic wellbeing has long been a subject of interest amongst geographers in North America. By contrast, relatively few Australian studies exist on this topic. This is despite the significant role of resource industries in shaping Australia's economic and social geography. Where research has been undertaken it tends to focus on the experience of a single town or region. This paper presents a cross-sectional analysis of socio-economic performance across 33 small mining towns in Western Australia. We design and test a number of empirical models that are hypothesised to account for the variability in socio-economic performance across different resource industry contexts. The results of the analysis suggest that socioeconomic wellbeing in these towns is highly variable, and contingent on a range of factors including the nature of the particular commodity, company structure, and location.
    Journal of Rural Studies 07/2012; 28(3). DOI:10.1016/j.jrurstud.2011.10.006 · 2.04 Impact Factor