PUMILIO, but not RBMX, binding is required for regulation of genomic stability by noncoding RNA NORAD
- 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.
Article and author information
Author details
Mahmoud M Elguindy
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.
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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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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