Functional similarities between HIV-1 Tat and DNA sequence-specific transcriptional activators

Virology. 1995 Feb 1;206(2):1150-4. doi: 10.1006/viro.1995.1041.


The Tat regulatory protein encoded by human immunodeficiency virus type 1 (HIV-1) induces high levels of transcription from the viral long terminal repeat (LTR) promoter element after interacting with a promoter proximal RNA target sequence. In the wild-type HIV-1 LTR, this activation is facilitated by the synergistic interaction of Tat with the NF-kappa B and, particularly, SP1 regulatory proteins that bind to DNA sequences within the LTR promoter element. Using a synthetic Tat responsive indicator construct, we here demonstrate that NF-kappa B and SP1 are not uniquely or even unusually competent to synergize with HIV-1 Tat. Instead, these proteins can be functionally replaced by several, but not all, of the heterologous cellular and viral transcriptional activators tested. Tat therefore shares the ability to functionally synergize with a range of transcriptional activators, which is characteristic of DNA-sequence-specific regulatory proteins.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Binding Sites
  • Cell Line
  • Chlorocebus aethiops
  • Cytomegalovirus / genetics
  • Cytomegalovirus / metabolism
  • DNA, Viral / metabolism*
  • Gene Products, tat / metabolism*
  • HIV Long Terminal Repeat*
  • HIV-1 / genetics
  • HIV-1 / metabolism*
  • Humans
  • Kidney
  • NF-kappa B / metabolism
  • Plasmids
  • Promoter Regions, Genetic
  • Recombinant Fusion Proteins / metabolism
  • Sp1 Transcription Factor / metabolism
  • Trans-Activators / metabolism*
  • Transcription, Genetic
  • Transcriptional Activation
  • Transfection
  • tat Gene Products, Human Immunodeficiency Virus


  • DNA, Viral
  • Gene Products, tat
  • NF-kappa B
  • Recombinant Fusion Proteins
  • Sp1 Transcription Factor
  • Trans-Activators
  • tat Gene Products, Human Immunodeficiency Virus