Tetracycline-regulated gene expression following direct gene transfer into mouse skeletal muscle
ABSTRACT For most experimental and therapeutic applications of gene transfer, regulation of the timing and level of gene expression is preferable to constitutive gene expression. Among the systems that have been developed for pharmacologically controlled gene expression in mammalian cells, the bacterial tetracycline (tet)-responsive system has the advantage that it is dependent on a drug (tet) that is both highly specific and non-toxic. The tet-responsive system has been previously used to modulate expression of cell cycle regulatory proteins in cultured cells, reporter genes in plants and transgenic mice and reporter genes directly injected into the heart. Here we show that orally or parenterally administered tet regulates expression of tet-responsive plasmids injected directly into mouse skeletal muscle. Reporter gene expression was suppressed by two orders of magnitude in the presence of tet, and that suppression was reversed when tet was withdrawn. These data show that skeletal muscle offers an accessible and well characterized target tissue for tet-controlled expression of genesin vivo, suggesting applications to developmental studies and gene therapy.
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ABSTRACT: Since 1990 when the first clinical gene therapy trial was conducted, much attention and considerable promise has been given to this form of treatment. Gene therapy has been used with success in patients suffering from severe combined immunodeficiency syndromes (X-SCID and ADA-deficiency), Leber's congenital amaurosis, hemophilia, β-thalassemia and adrenoleukodystrophy. Last year, the first therapeutic vector (Glybera) for treatment of lipoprotein lipase deficiency has been registred in European Union. Nevertheless, there are still several numerous issues that need to be improved to make this technique more safe, effective and easily accessible for patients. Introduction of the therapeutic gene to the given cells should provide the level of expression which will restore the production of therapeutic protein to normal values or will provide therapeutic efficacy despite not fully physiological expression. However, in numerous diseases the expression of therapeutic genes has to be kept at certain level for some time, and then might be required to be switched off to be activated again when worsening of the symptoms may aggravate the risk of disease relapse. In such cases the promoters which are regulated by local conditions may be more required. In this article the special emphasis is to discuss the strategies of regulation of gene expression by endogenous stimuli. Particularly, the hypoxia- or miRNA-regulated vectors offer the possibilities of tight but, at the same time, condition-dependent and cell-specific expression. Such means have been already tested in certain pathophysiological conditions. This creates the chance for the translational approaches required for development of effective treatments of so far incurable diseases.Gene 04/2013; · 2.20 Impact Factor
- Expert Opinion on Therapeutic Targets - EXPERT OPIN THER TARGETS. 01/1999; 3(1):27-39.
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ABSTRACT: Two gene constructs, pMTLuc and pRSVLuc, were microinjected into the muscle tissue of developing Macrobrachium lanchesteri (De Man) embryos. Both constructs expressed efficiently and the luciferase activities were still detectable 10 days after injection. PCR results demonstrated that pMTLuc persisted as long as and even beyond 10 days in some embryos. Embryos in their later developmental stages expressed higher levels of pRSVLuc than those in their early stage. Expression of pRSVLuc was occasionally detected when the plasmid was injected into the presumptive eyestalk area of the embryo.Aquaculture Research 02/1997; 28(3):183 - 190. · 1.42 Impact Factor