1. Chromosomes and Gene Expression
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HIV Tat controls RNA Polymerase II and the epigenetic landscape to transcriptionally reprogram target immune cells

  1. Jonathan E Reeder
  2. Youn-Tae Kwak
  3. Ryan P McNamara
  4. Christian V Forst
  5. Iván D'Orso  Is a corresponding author
  1. University of Texas at Dallas, United States
  2. University of Texas Southwestern Medical Center, United States
  3. Icahn School of Medicine at Mount Sinai, United States
Research Article
  • Cited 19
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Cite this article as: eLife 2015;4:e08955 doi: 10.7554/eLife.08955

Abstract

HIV encodes Tat, a small protein that facilitates viral transcription by binding an RNA structure (TAR) formed on nascent viral pre-mRNAs. Besides this well characterized mechanism, Tat appears to modulate cellular transcription, but the target genes and molecular mechanisms remain poorly understood. We report here that Tat uses unexpected regulatory mechanisms to reprogram target immune cells to promote viral replication and rewire pathways beneficial for the virus. Tat functions through master transcriptional regulators bound at promoters and enhancers, rather than through cellular 'TAR-like' motifs, to both activate and repress gene sets sharing common functional annotations. Despite the complexity of transcriptional regulatory mechanisms in the cell, Tat precisely controls RNA Polymerase II recruitment and pause release to fine-tune the initiation and elongation steps. We propose that a virus with a limited coding capacity optimized its genome by evolving a small but 'multitasking' protein to simultaneously control viral and cellular transcription.

Article and author information

Author details

  1. Jonathan E Reeder

    Biology, University of Texas at Dallas, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Youn-Tae Kwak

    Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Ryan P McNamara

    Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Christian V Forst

    Department of Genetics and Genomc Sciences, Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Iván D'Orso

    Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    Ivan.Dorso@UTSouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Michael R Green, Howard Hughes Medical Institute, University of Massachusetts Medical School, United States

Publication history

  1. Received: May 27, 2015
  2. Accepted: October 20, 2015
  3. Accepted Manuscript published: October 21, 2015 (version 1)
  4. Accepted Manuscript updated: October 22, 2015 (version 2)
  5. Version of Record published: January 19, 2016 (version 3)

Copyright

© 2015, Reeder et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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