Nuclear Factor 90(NF90) targeted to TAR RNA inhibits transcriptional activation of HIV-1

Retrovirology. 2007 Jun 12;4:41. doi: 10.1186/1742-4690-4-41.

Abstract

Background: Examination of host cell-based inhibitors of HIV-1 transcription may be important for attenuating viral replication. We describe properties of a cellular double-stranded RNA binding protein with intrinsic affinity for HIV-1 TAR RNA that interferes with Tat/TAR interaction and inhibits viral gene expression.

Results: Utilizing TAR affinity fractionation, North-Western blotting, and mobility-shift assays, we show that the C-terminal variant of nuclear factor 90 (NF90ctv) with strong affinity for the TAR RNA, competes with Tat/TAR interaction in vitro. Analysis of the effect of NF90ctv-TAR RNA interaction in vivo showed significant inhibition of Tat-transactivation of HIV-1 LTR in cells expressing NF90ctv, as well as changes in histone H3 lysine-4 and lysine-9 methylation of HIV chromatin that are consistent with the epigenetic changes in transcriptionally repressed gene.

Conclusion: Structural integrity of the TAR element is crucial in HIV-1 gene expression. Our results show that perturbation Tat/TAR RNA interaction by the dsRNA binding protein is sufficient to inhibit transcriptional activation of HIV-1.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Binding Sites
  • Cell Fractionation
  • Cell Line
  • Electrophoretic Mobility Shift Assay
  • Gene Products, tat / antagonists & inhibitors*
  • Gene Products, tat / metabolism
  • HIV Long Terminal Repeat
  • HIV-1 / immunology*
  • HeLa Cells
  • Histones / metabolism
  • Humans
  • Jurkat Cells
  • Methylation
  • Nuclear Factor 90 Proteins / physiology*
  • Protein Binding
  • RNA, Double-Stranded / metabolism
  • RNA, Viral / metabolism
  • RNA-Binding Proteins / physiology
  • Transcriptional Activation*
  • tat Gene Products, Human Immunodeficiency Virus

Substances

  • Gene Products, tat
  • Histones
  • Nuclear Factor 90 Proteins
  • RNA, Double-Stranded
  • RNA, Viral
  • RNA-Binding Proteins
  • tat Gene Products, Human Immunodeficiency Virus