1. Cell Biology
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Human Nup98 regulates the localization and activity of DExH/D-box helicase DHX9

  1. Juliana S Capitanio
  2. Ben Montpetit
  3. Richard W Wozniak  Is a corresponding author
  1. University of Alberta, Canada
Research Article
  • Cited 15
  • Views 2,761
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Cite this article as: eLife 2017;6:e18825 doi: 10.7554/eLife.18825

Abstract

Beyond their role at nuclear pore complexes, some nucleoporins function in the nucleoplasm. One such nucleoporin, Nup98, binds chromatin and regulates gene expression. To gain insight into how Nup98 contributes to this process, we focused on identifying novel binding partners and understanding the significance of these interactions. Here we report on the identification of the DExH/D-box helicase DHX9 as an intranuclear Nup98 binding partner. Various results, including in vitro assays, show that the FG/GLFG region of Nup98 binds to N- and C-terminal regions of DHX9 in an RNA facilitated manner. Importantly, binding of Nup98 stimulates the ATPase activity of DHX9, and a transcriptional reporter assay suggests Nup98 supports DHX9-stimulated transcription. Consistent with these observations, our analysis revealed that Nup98 and DHX9 bind interdependently to similar gene loci and their transcripts. Based on our results, we propose that Nup98 functions as a co-factor that regulates DHX9 and, potentially, other RNA helicases.

Data availability

The following previously published data sets were used
    1. Franks T
    2. Hetzer M
    (2016) DamID in HeLa-C cells
    Publicly available at the NCBI Gene Expression Omnibus (accession no: GSE83692).
    1. Hendrickson DG
    2. Kelley DR
    (2016) Widespread RNA Binding by Chromatin Associated Proteins
    Publicly available at the NCBI Gene Expression Omnibus (accession no: GSE67963).
    1. Franks T
    2. Hetzer M
    (2016) RNA-seq in HepG2 and IMR90 cells
    Publicly available at the NCBI Gene Expression Omnibus (accession no: GSE83551).

Article and author information

Author details

  1. Juliana S Capitanio

    Department of Cell Biology, University of Alberta, Edmonton, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Ben Montpetit

    Department of Cell Biology, University of Alberta, Edmonton, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8317-983X
  3. Richard W Wozniak

    Department of Cell Biology, University of Alberta, Edmonton, Canada
    For correspondence
    rick.wozniak@ualberta.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2328-0247

Funding

Alberta Innovates - Health Solutions (Graduate Studentship)

  • Juliana S Capitanio

Canadian Institutes of Health Research (MRC Operating Grant Program,130231)

  • Ben Montpetit

Canadian Institutes of Health Research (MRC Operating Grant Program,106502 and 36519)

  • Richard W Wozniak

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

Reviewing Editor

  1. Karsten Weis, ETH Zurich, Switzerland

Publication history

  1. Received: June 15, 2016
  2. Accepted: February 16, 2017
  3. Accepted Manuscript published: February 21, 2017 (version 1)
  4. Version of Record published: March 6, 2017 (version 2)

Copyright

© 2017, Capitanio 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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