Abstract
Sustained expression of recombinant proteins is a critical factor for the effectiveness of numerous applications in the biomedical sciences including the treatment of human disease by gene therapy, the large scale production of therapeutic proteins, as well as the investigation of gene function by transgenesis or cell type specific mutagenesis. Although much attention has been paid to the optimisation of regulatory sequences such as promoters, untranslated regions and polyadenylation signals, effective and sustained expression of recombinant genes in vivo is often difficult to achieve. Here we report that the creation of artificial exons, by insertion of two short heterologous introns into open reading frames, is not only compatible with functional expression, but also leads to a 30-fold enhancement of mRNA production for both green fluorescent protein and the bacteriophage P1-derived Cre recombinase. The levels of green fluorescence were increased five-fold in cell lines and sustained long-term expression at increased levels was observed in rat brain after transduction with a herpes simplex virus-based vector. The data presented identify a means by which the expression of recombinant genes can be enhanced considerably, in addition to and independently from the surrounding regulatory sequences. The method should help obtain sustained and effective expression of recombinant proteins in vivo.
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Acknowledgements
Experiments on animals were carried out in accordance to the regulations under the Home Office (United Kingdom) Animals (Scientific Procedures) Act 1986. ALH and RT contributed equally to this work. This work was supported by the Wellcome Trust grants 47608, 55287, 47273 the latter to J Savill, University of Edinburgh, whom we gratefully acknowledge for the support of ALH during the project.
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Lacy-Hulbert, A., Thomas, R., Li, XP. et al. Interruption of coding sequences by heterologous introns can enhance the functional expression of recombinant genes. Gene Ther 8, 649–653 (2001). https://doi.org/10.1038/sj.gt.3301440
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DOI: https://doi.org/10.1038/sj.gt.3301440
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