1. Biochemistry and Chemical Biology
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Coupling between the DEAD-box RNA helicases Ded1p and eIF4A

  1. Zhaofeng Gao
  2. Andrea A Putnam
  3. Heath A Bowers
  4. Ulf-Peter Guenther
  5. Xuan Ye
  6. Audrey Kindsfather
  7. Angela K Hilliker
  8. Eckhard Jankowsky  Is a corresponding author
  1. Case Western Reserve University, United States
  2. University of Richmond, United States
Research Article
  • Cited 31
  • Views 2,462
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Cite this article as: eLife 2016;5:e16408 doi: 10.7554/eLife.16408

Abstract

Eukaryotic translation initiation involves two conserved DEAD-box RNA helicases, eIF4A and Ded1p. Here we show that S. cerevisiae eIF4A and Ded1p directly interact with each other and simultaneously with the scaffolding protein eIF4G. We delineate a comprehensive thermodynamic framework for the interactions between Ded1p, eIF4A, eIF4G, RNA and ATP, which indicates that eIF4A, with and without eIF4G, acts as modulator for activity and substrate preferences of Ded1p, which is the RNA remodeling unit in all complexes. Our results reveal and characterize an unexpected interdependence between the two RNA helicases and eIF4G, and suggest that Ded1p is an integral part of eIF4F, the complex comprising eIF4G, eIF4A, and eIF4E.

Article and author information

Author details

  1. Zhaofeng Gao

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Andrea A Putnam

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Heath A Bowers

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Ulf-Peter Guenther

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Xuan Ye

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3157-7537
  6. Audrey Kindsfather

    Department of Biology, University of Richmond, Richmond, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Angela K Hilliker

    Department of Biology, University of Richmond, Richmond, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Eckhard Jankowsky

    Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, United States
    For correspondence
    exj13@case.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7677-7412

Funding

National Institute of General Medical Sciences (GM118088)

  • Zhaofeng Gao
  • Andrea A Putnam
  • Heath A Bowers
  • Ulf-Peter Guenther
  • Xuan Ye
  • Eckhard Jankowsky

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

Reviewing Editor

  1. Alan G Hinnebusch, National Institute of Child Health and Human Development, United States

Publication history

  1. Received: March 26, 2016
  2. Accepted: August 4, 2016
  3. Accepted Manuscript published: August 5, 2016 (version 1)
  4. Version of Record published: August 18, 2016 (version 2)

Copyright

© 2016, Gao 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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