Damaging the Integrated HIV Proviral DNA with TALENs

PLoS One. 2015 May 6;10(5):e0125652. doi: 10.1371/journal.pone.0125652. eCollection 2015.

Abstract

HIV-1 integrates its proviral DNA genome into the host genome, presenting barriers for virus eradication. Several new gene-editing technologies have emerged that could potentially be used to damage integrated proviral DNA. In this study, we use transcription activator-like effector nucleases (TALENs) to target a highly conserved sequence in the transactivation response element (TAR) of the HIV-1 proviral DNA. We demonstrated that TALENs cleave a DNA template with the HIV-1 proviral target site in vitro. A GFP reporter, under control of HIV-1 TAR, was efficiently inactivated by mutations introduced by transfection of TALEN plasmids. When infected cells containing the full-length integrated HIV-1 proviral DNA were transfected with TALENs, the TAR region accumulated indels. When one of these mutants was tested, the mutated HIV-1 proviral DNA was incapable of producing detectable Gag expression. TALEN variants engineered for degenerate recognition of select nucleotide positions also cleaved proviral DNA in vitro and the full-length integrated proviral DNA genome in living cells. These results suggest a possible design strategy for the therapeutic considerations of incomplete target sequence conservation and acquired resistance mutations. We have established a new strategy for damaging integrated HIV proviral DNA that may have future potential for HIV-1 proviral DNA eradication.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Binding Sites / genetics
  • Cell Line, Tumor
  • Conserved Sequence / genetics
  • DNA Damage / drug effects
  • DNA Restriction Enzymes / pharmacology*
  • DNA, Viral / genetics*
  • HIV Infections / genetics
  • HIV-1 / genetics*
  • HeLa Cells
  • Humans
  • Proviruses / genetics*
  • Response Elements / genetics*
  • Virus Integration

Substances

  • DNA, Viral
  • DNA Restriction Enzymes