Lens epithelium-derived growth factor fusion proteins redirect HIV-1 DNA integration

Proc Natl Acad Sci U S A. 2010 Feb 16;107(7):3135-40. doi: 10.1073/pnas.0914142107. Epub 2010 Feb 1.

Abstract

Lens epithelium-derived growth factor (LEDGF) fusion proteins can direct HIV-1 DNA integration to novel sites in the host genome. The C terminus of LEDGF contains an integrase binding domain (IBD), and the N terminus binds chromatin. LEDGF normally directs integrations to the bodies of expressed genes. Replacing the N terminus of LEDGF with chromatin binding domains (CBDs) from other proteins changes the specificity of HIV-1 DNA integration. We chose two well-characterized CBDs: the plant homeodomain (PHD) finger from ING2 and the chromodomain from heterochromatin binding protein 1alpha (HP1alpha). The ING2 PHD finger binds H3K4me3, a histone mark that is associated with the transcriptional start sites of expressed genes. The HP1alpha chromodomain binds H3K9me2,3, histone marks that are widely distributed throughout the genome. A fusion protein in which the ING2 PHD finger was linked to the LEDGF IBD directed integrations near the start sites of expressed genes. A similar fusion protein in which the HP1alpha chromodomain was linked to the LEDGF IBD directed integrations to sites that differed from both the PHD finger fusion-directed and LEDGF-directed integration sites. The ability to redirect HIV-1 DNA integration may help solve the problems associated with the activation of oncogenes when retroviruses are used in gene therapy.

Publication types

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

MeSH terms

  • Animals
  • Binding Sites / genetics
  • Cell Line
  • Chromatin / metabolism
  • Computational Biology
  • DNA, Viral / genetics
  • DNA, Viral / metabolism*
  • Flow Cytometry
  • Gene Expression Profiling
  • Genetic Therapy / methods
  • HIV Integrase / metabolism
  • HIV-1*
  • Homeodomain Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / metabolism*
  • Mice
  • Mice, Knockout
  • Protein Structure, Tertiary / genetics
  • Protein Structure, Tertiary / physiology
  • Sequence Analysis, DNA
  • Tumor Suppressor Proteins / genetics
  • Virus Integration / physiology*

Substances

  • Chromatin
  • DNA, Viral
  • Homeodomain Proteins
  • ING2 protein, mouse
  • Intercellular Signaling Peptides and Proteins
  • Tumor Suppressor Proteins
  • lens epithelium-derived growth factor
  • HIV Integrase