ShRNAs lentiviruses

To produce stable and long-lasting knockdown, viral vectors have been developed to efficiently express siRNAs or short hairpin RNAs (shRNAs) in a wide variety of mammalian cells (Fig. 8). Expression vectors include standard plasmids as well as those made from adenoviruses, adeno-associated viruses (AAVs), onco-retroviruses, and lentiviruses. The viral expression systems have the added benefit of being able to deliver siRNA, shRNA, or miRNA expression cassettes efficiently into cell types that are otherwise difficult to transfect via common transfection or electroporation protocols.f ... 

Herold MJ, van den Brandt J, Seibler J, et al. Inducible and reversible gene silencing by stable integration of an shRNA-encoding lentivirus in transgenic rats. Proc Natl Acad Sci USA. 2008 105 18507-18512. 

Lentiviruses can infect non-dividing cells, thereby allowing stable gene transfer in post-mitotic mature neurons. Lentiviral vector-mediated delivery of short hairpin RNAs (shRNAs) results in persistent knockdown of gene expression. In addition, inducible lentiviral vectors offer a powerful tool for better assessing the function of a gene candidate in targeted neurons by an on-off system [1]. 

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