Insights into HIV-1 proviral transcription from the structure and dynamics of the Tat:AFF4:P-TEFb:TAR complex

  1. Ursula Schulze-Gahmen
  2. Ignacia Echeverria
  3. Goran Stjepanovic
  4. Yun Bai
  5. Huasong Lu
  6. Dina Schneidman-Duhovny
  7. Jennifer A Doudna
  8. Qiang Zhou
  9. Andrej Sali
  10. James H Hurley  Is a corresponding author
  1. University of California, Berkeley, United States
  2. University of California, San Francisco, United States

Abstract

HIV-1 Tat hijacks the human superelongation complex (SEC) to promote proviral transcription. Here we report the 5.9 Å structure of HIV-1 TAR in complex with HIV-1 Tat and human AFF4, CDK9, and CycT1. The TAR central loop contacts the CycT1 Tat-TAR recognition motif (TRM) and the second Tat Zn2+-binding loop. Hydrogen-deuterium exchange (HDX) shows that AFF4 helix 2 is stabilized in the TAR complex despite not touching the RNA, explaining how it enhances TAR binding to the SEC 50-fold. RNA SHAPE and SAXS data were used to help model the extended (Tat Arginine-Rich Motif) ARM, which enters the TAR major groove between the bulge and the central loop. The structure and functional assays collectively support a bipartite model, wherein the TAR central loop engages the CycT1 TRM and compact core of Tat, while the TAR major groove interacts with the extended Tat ARM.

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Author details

  1. Ursula Schulze-Gahmen

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ignacia Echeverria

    Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4717-1467
  3. Goran Stjepanovic

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4841-9949
  4. Yun Bai

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Huasong Lu

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Dina Schneidman-Duhovny

    Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Jennifer A Doudna

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Qiang Zhou

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Andrej Sali

    Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. James H Hurley

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    jimhurley@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5054-5445

Funding

National Institute of General Medical Sciences

  • James H Hurley

National Institute of Allergy and Infectious Diseases

  • Qiang Zhou

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Axel T Brunger, Stanford University Medical Center, United States

Version history

  1. Received: March 9, 2016
  2. Accepted: October 7, 2016
  3. Accepted Manuscript published: October 12, 2016 (version 1)
  4. Version of Record published: October 20, 2016 (version 2)
  5. Version of Record updated: October 21, 2016 (version 3)

Copyright

© 2016, Schulze-Gahmen 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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  1. Ursula Schulze-Gahmen
  2. Ignacia Echeverria
  3. Goran Stjepanovic
  4. Yun Bai
  5. Huasong Lu
  6. Dina Schneidman-Duhovny
  7. Jennifer A Doudna
  8. Qiang Zhou
  9. Andrej Sali
  10. James H Hurley
(2016)
Insights into HIV-1 proviral transcription from the structure and dynamics of the Tat:AFF4:P-TEFb:TAR complex
eLife 5:e15910.
https://doi.org/10.7554/eLife.15910

Share this article

https://doi.org/10.7554/eLife.15910

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