Expression of interfering RNAs from an HIV-1 Tat-inducible chimeric promoter.
The therapeutic value of antiviral interfering RNAs could be improved by technologies that limit their expression to the infected cell population. The HIV-1 Tat-inducible viral LTR and LTR-containing chimeric promoters have previously been used to drive expression of antiviral RNAs and proteins directed against HIV-1. Here, we characterize an alternative promoter, consisting of a chicken β-actin core promoter fused to the viral TAR element, for the conditional expression of interfering RNAs. This promoter, that we refer to as the CK-TAR promoter, can induce levels of silencing comparable to the viral LTR in response to Tat produced from co-transfected plasmids or during viral replication. While the CK-TAR promoter shows a modest level of basal activity, similar to the viral LTR, it is less responsive to the extracellular stimuli tested including LPS, TNFα, and PMA. The CK-TAR promoter is an alternative Tat-inducible promoter with the potential to minimize the risk of vector mobilization and to drive polycistronic expression of interfering RNAs.
Sanghvi
Viraj R
VR
Department of Microbiology and Immunology, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, 245 North 15th Street, Philadelphia, PA 19102, USA.
Steel
Laura F
LF
D000199:Actins / Q000235:genetics; D000818:Animals; D019677:Artificial Gene Fusion; D002460:Cell Line; D002645:Chickens; D016325:HIV Long Terminal Repeat; D006801:Humans; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000096:biosynthesis*; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*
D000199:Actins; D034741:RNA, Small Interfering; D054322:tat Gene Products, Human Immunodeficiency Virus