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Lentiviral Vector Platform for the Efficient Delivery of Epigenome-editing Tools into Human Induced Pluripotent Stem Cell-derived Disease Models
Published on: March 29, 2019
OTK18, a zinc-finger protein, regulates human immunodeficiency virus type 1 long terminal repeat through two distinct
Masahide Horiba1,2, Lindsey B Martinez1,2, James L Buescher1,2
1Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5880, USA.
Abstract:
It has previously been shown by our laboratory that OTK18, a human immunodeficiency virus (HIV)-inducible zinc-finger protein, reduces progeny-virion production in infected human macrophages. OTK18 antiviral activity is mediated through suppression of Tat-induced HIV-1 long terminal repeat (LTR) promoter activity. Through the use of LTR-scanning mutant vectors, the specific regions responsible for OTK18-mediated LTR suppression have been defined. Two different LTR regions were identified as potential OTK18-binding sites by an enhanced DNA-transcription factor ELISA system; the negative-regulatory element (NRE) at -255/-238 and the Ets-binding site (EBS) at -150/-139 in the LTR. In addition, deletion of the EBS in the LTR blocked OTK18-mediated LTR suppression. These data indicate that OTK18 suppresses LTR activity through two distinct regulatory elements. Spontaneous mutations in these regions might enable HIV-1 to escape from OTK18 antiretroviral activity in human macrophages.
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