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.
Metrics
-
- 4,179
- views
-
- 576
- downloads
-
- 60
- 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)
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
Further reading
-
- Chromosomes and Gene Expression
- Microbiology and Infectious Disease
Candida glabrata can thrive inside macrophages and tolerate high levels of azole antifungals. These innate abilities render infections by this human pathogen a clinical challenge. How C. glabrata reacts inside macrophages and what is the molecular basis of its drug tolerance are not well understood. Here, we mapped genome-wide RNA polymerase II (RNAPII) occupancy in C. glabrata to delineate its transcriptional responses during macrophage infection in high temporal resolution. RNAPII profiles revealed dynamic C. glabrata responses to macrophages with genes of specialized pathways activated chronologically at different times of infection. We identified an uncharacterized transcription factor (CgXbp1) important for the chronological macrophage response, survival in macrophages, and virulence. Genome-wide mapping of CgXbp1 direct targets further revealed its multi-faceted functions, regulating not only virulence-related genes but also genes associated with drug resistance. Finally, we showed that CgXbp1 indeed also affects fluconazole resistance. Overall, this work presents a powerful approach for examining host-pathogen interaction and uncovers a novel transcription factor important for C. glabrata’s survival in macrophages and drug tolerance.
-
- Chromosomes and Gene Expression
- Neuroscience
Pathogenic variants in subunits of RNA polymerase (Pol) III cause a spectrum of Polr3-related neurodegenerative diseases including 4H leukodystrophy. Disease onset occurs from infancy to early adulthood and is associated with a variable range and severity of neurological and non-neurological features. The molecular basis of Polr3-related disease pathogenesis is unknown. We developed a postnatal whole-body mouse model expressing pathogenic Polr3a mutations to examine the molecular mechanisms by which reduced Pol III transcription results primarily in central nervous system phenotypes. Polr3a mutant mice exhibit behavioral deficits, cerebral pathology and exocrine pancreatic atrophy. Transcriptome and immunohistochemistry analyses of cerebra during disease progression show a reduction in most Pol III transcripts, induction of innate immune and integrated stress responses and cell-type-specific gene expression changes reflecting neuron and oligodendrocyte loss and microglial activation. Earlier in the disease when integrated stress and innate immune responses are minimally induced, mature tRNA sequencing revealed a global reduction in tRNA levels and an altered tRNA profile but no changes in other Pol III transcripts. Thus, changes in the size and/or composition of the tRNA pool have a causal role in disease initiation. Our findings reveal different tissue- and brain region-specific sensitivities to a defect in Pol III transcription.
