Small Nucleolar RNAs U32a, U33, and U35a Are Critical Mediators of Metabolic Stress

Michel, Carlos I.; Holley, Christopher L.; Scruggs, Benjamin S.; Sidhu, Rohini; Brookheart, Rita T.; Listenberger, Laura L.; Behlke, Mark A.; Ory, Daniel S.; Schaffer, Jean E.

doi:10.1016/j.cmet.2011.04.009

Cited by 213 publications

(220 citation statements)

References 47 publications

Supporting

Mentioning

207

Contrasting

Unclassified

Order By: Relevance

“…Our previous studies have shown that following exposure to lipotoxic conditions, snoRNAs from the rpL13a locus accumulate in the cytosol and function as essential mediators of cell death. 22 Based on the requirement of RNase activity for complementation, we hypothesized that the biochemical function of RNASET2 during lipotoxicity might contribute to the biogenesis of the rpL13a snoRNAs. To test this possibility, we compared RNASET2-deficient 2B1 and WT CHO cells for cytosolic accumulation of the rpL13a snoRNAs in response to palm treatment.…”

Section: Resultsmentioning

confidence: 99%

“…24,31 The observation that treatment of cells with more direct inducers of oxidative stress, such as hydrogen peroxide, also causes cytoplasmic snoRNA accumulation suggests that ROS may be an upstream signal for the redistribution of snoRNAs. 22 Because cells haploinsufficient for RNASET2 fail to accumulate the rpL13a snoRNAs in the cytoplasm, but have no apparent defect in the generation of these snoRNAs (that is, nuclear levels are unchanged), we tested whether haploinsufficiency of RNASET2 modulated the generation of ROS in response to palm. Following supplementation of the media with palm, we quantified cellular superoxide by dihydroethidium (DHE) staining, and cellular hydrogen peroxide by 2′, 7′-dichlorodihydrofluorescein diacetate (DCF) staining.…”

Section: Resultsmentioning

confidence: 99%

“…RNA was isolated using TRIzol or TRIzol LS reagent and reverse transcribed to cDNA (SuperScript III First-Strand Synthesis System, Life Technologies) by priming with oligo(dT) to detect mRNA or random hexamers to detect pre-mRNA, intron lariats, and ribosomal RNA. For detection of snoRNAs and tRNAs, cDNA synthesis was primed with hairpin stem-loop oligonucleotides as previously described, 22 with overhang complementarity to the 3′ end of the processed snoRNA or tRNA. For detection of rRNA, RNA was extracted and reverse transcribed using random hexamers, normalizing per cell number.…”

Section: Discussionmentioning

confidence: 99%

“…We found that cells become resistant to death from lipotoxic and generalized oxidative stress stimuli upon disruption of small nucleolar RNAs (snoRNAs) encoded within the ribosomal protein L13a (rpL13a) locus or disruption of expression of a splicosomal protein necessary for production of these non-coding RNAs from intron lariats. 22,23 The mechanism of action of these non-coding RNAs is an area of active investigation. Herein, we describe findings from a completely independent mutant isolated from this genetic screen in which an allele encoding RNASET2 was disrupted.…”

mentioning

confidence: 99%

See 3 more Smart Citations

RNASET2 is required for ROS propagation during oxidative stress-mediated cell death

et al. 2015

View full text Add to dashboard Cite

RNASET2 is a ubiquitously expressed acidic ribonuclease that has been implicated in diverse pathophysiological processes including tumorigeneis, vitiligo, asthenozoospermia, and neurodegeneration. Prior studies indicate that RNASET2 is induced in response to oxidative stress and that overexpression of RNASET2 sensitizes cells to reactive oxygen species (ROS)-induced cell death through a mechanism that is independent of catalytic activity. Herein, we report a loss-of-function genetic screen that identified RNASET2 as an essential gene for lipotoxic cell death. Haploinsufficiency of RNASET2 confers increased antioxidant capacity and generalized resistance to oxidative stress-mediated cell death in cultured cells. This function is critically dependent on catalytic activity. Furthermore, knockdown of RNASET2 in the Drosophila fat body confers increased survival in the setting of oxidative stress inducers. Together, these findings demonstrate that RNASET2 regulates antioxidant tone and is required for physiological ROS responses.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

RNASET2 is required for ROS propagation during oxidative stress-mediated cell death

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Our studies suggest yet another function for snoRNAs, in particular, as signals of metabolic stress. Here we note that snoRNAs have been previously linked to lipotoxicity (25), and cells deficient in intronic snoRNAs are resistant to cell death induced by PA treatment (40).…”

Section: Discussionmentioning

confidence: 99%

Potential role for snoRNAs in PKR activation during metabolic stress

Youssef

Safran

Nakamura

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

104

103

View full text Add to dashboard Cite

Protein kinase RNA-activated (PKR) has long been known to be activated by viral double-stranded RNA (dsRNA) as part of the mammalian immune response. However, in mice PKR is also activated by metabolic stress in the absence of viral infection, and this requires a functional kinase domain, as well as a functional dsRNA-binding domain. The endogenous cellular RNA that potentially leads to PKR activation during metabolic stress is unknown. We investigated this question using mouse embryonic fibroblast cells expressing wild-type PKR (PKR WT ) or PKR with a point mutation in each dsRNA-binding motif (PKR RM ). Using this system, we identified endogenous RNA that interacts with PKR after induction of metabolic stress by palmitic acid (PA) treatment. Specifically, RIP-Seq analyses showed that the majority of enriched RNAs that interacted with WT PKR (≥twofold, false discovery rate ≤ 5%) were small nucleolar RNAs (snoRNAs). Immunoprecipitation of PKR in extracts of UV-cross-linked cells, followed by RT-qPCR, confirmed that snoRNAs were enriched in PKR WT samples after PA treatment, but not in the PKR RM samples. We also demonstrated that a subset of identified snoRNAs bind and activate PKR in vitro; the presence of a 5′-triphosphate enhanced PKR activity compared with the activity with a 5′-monophosphate, for some, but not all, snoRNAs. Finally, we demonstrated PKR activation in cells upon snoRNA transfection, supporting our hypothesis that endogenous snoRNAs can activate PKR. Our results suggest an unprecedented and unexpected model whereby snoRNAs play a role in the activation of PKR under metabolic stress.PKR | snoRNA | metabolic stress | phosphorylation | RNA-binding protein

show abstract