By a News Reporter-Staff News Editor at Biotech Week -- Researchers detail new data in Enzymes and Coenzymes. According to news reporting originating from Tours, France, by NewsRx correspondents, research stated, "Up to now, the different uptake pathways and the subsequent intracellular trafficking of plasmid DNA have been largely explored. By contrast, the mode of internalization and the intracellular routing of an exogenous mRNA in transfected cells are poorly investigated and remain to be elucidated."
Our news editors obtained a quote from the research from National Center for Scientific Research (CNRS), "The bioavailability of internalized mRNA depends on its intracellular routing and its potential accumulation in dynamic sorting sites for storage: stress granules and processing bodies. This question is of particular significance when a secure transposon-based system able to integrate a therapeutic transgene into the genome is used. Transposon vectors usually require two components: a plasmid DNA, carrying the gene of interest, and a source of transposase allowing the integration of the transgene. The principal drawback is the lasting presence of the transposase, which could remobilize the transgene once it has been inserted. Our study focused on the pharmacokinetics of the transposition process mediated by the piggyBac transposase mRNA transfection. Exogenous mRNA internalization and trafficking were investigated towards a better apprehension and fine control of the piggyBac transposase bioavailability. The mRNA prototype designed in this study provides a very narrow expression window of transposase, which allows high efficiency transposition with no cytotoxicity. Our data reveal that exogenous transposase mRNA enters cells by clathrin and caveolae-mediated endocytosis, before finishing in late endosomes 3 h after transfection. At this point, the mRNA is dissociated from its carrier and localized in stress granules, but not in cytoplasmic processing bodies. Some weaker signals have been observed in stress granules at 18 h and 48 h without causing prolonged production of the transposase. So, we designed an mRNA that is efficiently translated with a peak of transposase production 18 h post-transfection without additional release of the molecule. This confines the integration of the transgene in a very small time window. Our results shed light on processes of exogenous mRNA trafficking, which are crucial to estimate the mRNA bioavailability, and increase the biosafety of transgene integration mediated by transposition."
According to the news editors, the research concluded: "This approach provides a new way for limiting the transgene copy in the genome and their remobilization by mRNA engineering and trafficking."
For more information on this research see: Exogenous mRNA delivery and bioavailability in gene transfer mediated by piggyBac transposition. Bmc Biotechnology, 2013;13():75. (BioMed Central - www.biomedcentral.com/; Bmc Biotechnology - www.biomedcentral.com/bmcbiotechnol/)
The news editors report that additional information may be obtained by contacting S. Bire, LNOX, GICC UMR CNRS 7292, UFR de Medecine, Batiment Dutrochet, 10 Boulevard Tonnelle, Tours 37000, France. Additional authors for this research include D. Gosset, G. Jegot, P. Midoux, C. Pichon and F. Rouleux-Bonnin (see also Enzymes and Coenzymes).
Keywords for this news article include: Tours, France, Europe, Integrases, Transposases, Enzymes and Coenzymes, Nucleotidyltransferases.
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC