PUMILIO, but not RBMX, binding is required for regulation of genomic stability by noncoding RNA NORAD

  1. Mahmoud M Elguindy
  2. Florian Kopp
  3. Mohammad Goodarzi
  4. Frederick Rehfeld
  5. Anu Thomas
  6. Tsung-Cheng Chang
  7. Joshua T Mendell  Is a corresponding author
  1. University of Texas Southwestern Medical Center, United States

Abstract

NORAD is a conserved long noncoding RNA (lncRNA) that is required for genome stability in mammals, and which acts as a negative regulator of PUMILIO (PUM) proteins in the cytoplasm. Previously we showed that loss of NORAD or PUM hyperactivity results in premature aging in mice (Kopp et al., 2019). Recently, however, it was reported that NORAD regulates genome stability through an interaction with the RNA binding protein RBMX in the nucleus. Here we addressed the contributions of NORAD:PUM and NORAD:RBMX interactions to genome maintenance by this lncRNA in human cells. Extensive RNA FISH and fractionation experiments established that NORAD localizes predominantly to the cytoplasm with or without DNA damage. Moreover, genetic rescue experiments demonstrated that PUM binding is required for maintenance of genomic stability by NORAD whereas binding of RBMX is dispensable for this function. These data provide an important foundation for further mechanistic dissection of the NORAD-PUMILIO axis in genome maintenance.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

The following previously published data sets were used

Article and author information

Author details

  1. Mahmoud M Elguindy

    Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9151-1751
  2. Florian Kopp

    Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9952-635X
  3. Mohammad Goodarzi

    Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Frederick Rehfeld

    Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2751-1025
  5. Anu Thomas

    Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Tsung-Cheng Chang

    Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Joshua T Mendell

    Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    joshua.mendell@utsouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8479-2284

Funding

Cancer Prevention and Research Institute of Texas (RP160249)

  • Joshua T Mendell

National Institutes of Health (R35CA197311)

  • Joshua T Mendell

National Institutes of Health (P30CA142543)

  • Joshua T Mendell

National Institutes of Health (P50CA196516)

  • Joshua T Mendell

Welch Foundation (I-1961-20180324)

  • Joshua T Mendell

Howard Hughes Medical Institute

  • Joshua T Mendell

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

Reviewing Editor

  1. Chris P Ponting, University of Edinburgh, United Kingdom

Publication history

  1. Received: May 22, 2019
  2. Accepted: July 22, 2019
  3. Accepted Manuscript published: July 25, 2019 (version 1)
  4. Version of Record published: August 2, 2019 (version 2)

Copyright

© 2019, Elguindy 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. Mahmoud M Elguindy
  2. Florian Kopp
  3. Mohammad Goodarzi
  4. Frederick Rehfeld
  5. Anu Thomas
  6. Tsung-Cheng Chang
  7. Joshua T Mendell
(2019)
PUMILIO, but not RBMX, binding is required for regulation of genomic stability by noncoding RNA NORAD
eLife 8:e48625.
https://doi.org/10.7554/eLife.48625

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