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

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.

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.

Metrics

  • 3,630
    views
  • 651
    downloads
  • 32
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Juliana S Capitanio
  2. Ben Montpetit
  3. Richard W Wozniak
(2017)
Human Nup98 regulates the localization and activity of DExH/D-box helicase DHX9
eLife 6:e18825.
https://doi.org/10.7554/eLife.18825

Share this article

https://doi.org/10.7554/eLife.18825

Further reading

    1. Cell Biology
    Jittoku Ihara, Yibin Huang ... Koichi Yamamoto
    Research Article

    Chronic kidney disease (CKD) and atherosclerotic heart disease, frequently associated with dyslipidemia and hypertension, represent significant health concerns. We investigated the interplay among these conditions, focusing on the role of oxidized low-density lipoprotein (oxLDL) and angiotensin II (Ang II) in renal injury via G protein αq subunit (Gq) signaling. We hypothesized that oxLDL enhances Ang II-induced Gq signaling via the AT1 (Ang II type 1 receptor)-LOX1 (lectin-like oxLDL receptor) complex. Based on CHO and renal cell model experiments, oxLDL alone did not activate Gq signaling. However, when combined with Ang II, it significantly potentiated Gq-mediated inositol phosphate 1 production and calcium influx in cells expressing both LOX-1 and AT1 but not in AT1-expressing cells. This suggests a critical synergistic interaction between oxLDL and Ang II in the AT1-LOX1 complex. Conformational studies using AT1 biosensors have indicated a unique receptor conformational change due to the oxLDL-Ang II combination. In vivo, wild-type mice fed a high-fat diet with Ang II infusion presented exacerbated renal dysfunction, whereas LOX-1 knockout mice did not, underscoring the pathophysiological relevance of the AT1-LOX1 interaction in renal damage. These findings highlight a novel mechanism of renal dysfunction in CKD driven by dyslipidemia and hypertension and suggest the therapeutic potential of AT1-LOX1 receptor complex in patients with these comorbidities.

    1. Cell Biology
    Qi Zeng, Chen Yao ... Shuai Chen
    Research Article

    Mounting evidence has demonstrated the genetic association of ORMDL sphingolipid biosynthesis regulator 3 (ORMDL3) gene polymorphisms with bronchial asthma and a diverse set of inflammatory disorders. However, its role in type I interferon (type I IFN) signaling remains poorly defined. Herein, we report that ORMDL3 is a negative modulator of the type I IFN signaling by interacting with mitochondrial antiviral signaling protein (MAVS) and subsequently promoting the proteasome-mediated degradation of retinoic acid-inducible gene I (RIG-I). Immunoprecipitation coupled with mass spectrometry (IP-MS) assays uncovered that ORMDL3 binds to ubiquitin-specific protease 10 (USP10), which forms a complex with and stabilizes RIG-I through decreasing its K48-linked ubiquitination. ORMDL3 thus disrupts the interaction between USP10 and RIG-I, thereby promoting RIG-I degradation. Additionally, subcutaneous syngeneic tumor models in C57BL/6 mice revealed that inhibition of ORMDL3 enhances anti-tumor efficacy by augmenting the proportion of cytotoxic CD8 positive T cells and IFN production in the tumor microenvironment (TME). Collectively, our findings reveal the pivotal roles of ORMDL3 in maintaining antiviral innate immune responses and anti-tumor immunity.