Similar Datasets
Project description:Gene functional study and the emerging mRNA therapy technology heavily rely on in vitro transcribed (IVT) mRNA, but the double-stranded RNA (dsRNA) by-product generated during IVT is often recognized by cells as a marker of virus replication, leading to the integrated stress response (ISR).The biological effects of dsRNA in undifferentiated cells differ significantly from those of differentiated counterparts.Here, we found that dsRNA triggered an unprecedented ISR in zebrafish early embryos, leading to developmental delay, severe cell necrosis, and lethal malformations.Mechanistically, dsRNA stimulation caused a PKR-eIF2α independent global translation inhibition and a burst of p53 signaling. In turn, p53 activated Interferon Stimulated Genes (ISGs) and other defense-related genes in the absence of the IFN system. Unexpectedly, p53 does not promote cell death; instead, it plays a protective role in weakening the damage of translation repression by compromising protein turnover via enhanced ISGylation.This study thus unveils a distinct ISR upon dsRNA stimulation, which may help perform faithful gene overexpression in early embryos and shed light on the strategies of undifferentiated cells against RNA virus infection.
2024-01-01 | GSE234229 | GEO
Project description:Gene functional study and the emerging mRNA therapy technology heavily rely on in vitro transcribed (IVT) mRNA, but the double-stranded RNA (dsRNA) by-product generated during IVT is often recognized by cells as a marker of virus replication, leading to the integrated stress response (ISR).The biological effects of dsRNA in undifferentiated cells differ significantly from those of differentiated counterparts.Here, we found that dsRNA triggered an unprecedented ISR in zebrafish early embryos, leading to developmental delay, severe cell necrosis, and lethal malformations.Mechanistically, dsRNA stimulation caused a PKR-eIF2α independent global translation inhibition and a burst of p53 signaling. In turn, p53 activated Interferon Stimulated Genes (ISGs) and other defense-related genes in the absence of the IFN system. Unexpectedly, p53 does not promote cell death; instead, it plays a protective role in weakening the damage of translation repression by compromising protein turnover via enhanced ISGylation.This study thus unveils a distinct ISR upon dsRNA stimulation, which may help perform faithful gene overexpression in early embryos and shed light on the strategies of undifferentiated cells against RNA virus infection.
2024-01-01 | GSE234227 | GEO
Project description:Double-stranded RNA (dsRNA) is associated with virus infections and is present as by-products during the transcription of synthetic mRNA, which has been widely used in gene gain-of-function studies and serves as a core component in emerging mRNA-based therapies1-4. The presence of dsRNA in host cells induces an integrated stress response that functions to prevent virus replication and infection5,6. Unlike differentiated cells, undifferentiated cells adopt a distinct defense strategy against RNA virus infection7, but the mechanism is unclear. We show a previously unidentified response triggered by dsRNA in the early embryo. Although dsRNA causes a global protein translation inhibition in a PKR-eIF2α independent manner and leads to developmental delay and cell necrosis, it also strongly induces p53 activation, which then upregulates Interferon Stimulated Genes independently of interferon ligands. Importantly, we demonstrate that the burst of p53 signaling dose not result in cell death but functions as a protective mechanism against deleterious translation blockage by slowing down global protein degradation via ISGylation. Our work has identified a distinct dsRNA-induced stress response in the embryo, reflecting an ancient innate immune memory before the establishment of the IFN system. It also raises the provocative question as to the original protective role of p53 during evolution.
2024-04-26 | GSE265771 | GEO
Project description:Double-stranded RNA triggers a distinct integrated stress response in the early embryo
| PRJNA980581 | ENA
Project description:Double-stranded RNA triggers a distinct integrated stress response in the early embryo [cas9 tol2]
| PRJNA980585 | ENA
Project description:Double-stranded RNA triggers a distinct integrated stress response in the early embryo [dsRNA tp53]
| PRJNA980587 | ENA
Project description:Double-stranded RNA triggers a distinct integrated stress response in the early embryo [RNA-seq, Ribo-seq]
| PRJNA1104180 | ENA
Project description:Mitochondria are descendants of endosymbiotic bacteria and retain essential prokaryotic features such as a compact circular genome. Consequently, in mammals, mitochondrial DNA is subjected to bidirectional transcription that generates overlapping transcripts, which are capable of forming long double-stranded RNA structures1,2. However, to our knowledge, mitochondrial double-stranded RNA has not been previously characterized in vivo. Here we describe the presence of a highly unstable native mitochondrial double-stranded RNA species at single-cell level and identify key roles for the degradosome components mitochondrial RNA helicase SUV3 and polynucleotide phosphorylase PNPase in restricting the levels of mitochondrial double-stranded RNA. Loss of either enzyme results in massive accumulation of mitochondrial double-stranded RNA that escapes into the cytoplasm in a PNPase-dependent manner. This process engages an MDA5-driven antiviral signalling pathway that triggers a type I interferon response. Consistent with these data, patients carrying hypomorphic mutations in the gene PNPT1, which encodes PNPase, display mitochondrial double-stranded RNA accumulation coupled with upregulation of interferon-stimulated genes and other markers of immune activation. The localization of PNPase to the mitochondrial inter-membrane space and matrix suggests that it has a dual role in preventing the formation and release of mitochondrial double-stranded RNA into the cytoplasm. This in turn prevents the activation of potent innate immune defence mechanisms that have evolved to protect vertebrates against microbial and viral attack.
| S-EPMC6570621 | biostudies-literature
Project description:In eukaryotes, tRNAs are transcribed in the nucleus and exported to the cytosol, where they deliver amino acids to ribosomes for protein translation. This nuclear-cytoplasmic movement was believed to be unidirectional. However, active shuttling of tRNAs, named tRNA retrograde transport, between the cytosol and nucleus has been discovered. This pathway is conserved in eukaryotes, suggesting a fundamental function; however, little is known about its role in human cells. Here we report that, in human cells, oxidative stress triggers tRNA retrograde transport, which is rapid, reversible, and selective for certain tRNA species, mostly with shorter 3' ends. Retrograde transport of tRNASeC, which promotes translation of selenoproteins required to maintain homeostatic redox levels in cells, is highly efficient. tRNA retrograde transport is regulated by the integrated stress response pathway via the PERK-REDD1-mTOR axis. Thus, we propose that tRNA retrograde transport is part of the cellular response to oxidative stress.
| S-EPMC6426654 | biostudies-literature
Project description:The airway epithelial barrier is critical for preventing pathogen invasion and translocation of inhaled particles into the lung. Epithelial cells also serve an important sentinel role after infection and release various pro-inflammatory mediators that recruit and activate immune cells. Airway epithelial barrier disruption has been implicated in a growing number of respiratory diseases including viral infections. It is thought that when a pathogen breaks the barrier and gains access to the host tissue, pro-inflammatory mediators increase, which further disrupts the barrier and initiates a vicious cycle of leak. However, it is difficult to study airway barrier integrity in vivo, and little is known about relationship between epithelial barrier function and airway inflammation. Current assays of pulmonary barrier integrity quantify the leak of macromolecules from the vasculature into the airspaces (or "inside/out" leak). However, it is also important to measure the ease with which inhaled particles, allergens, or pathogens can enter the subepithelial tissues (or "outside/in" leak). We challenged mice with inhaled double stranded RNA (dsRNA) and explored the relationship between inside/out and outside/in barrier function and airway inflammation. Using wild-type and gene-targeted mice, we studied the roles of the dsRNA sensors Toll Like Receptor 3 (TLR3) and Melanoma Differentiation-Associated protein 5 (MDA5). Here we report that after acute challenge with inhaled dsRNA, airway barrier dysfunction occurs in a TLR3-dependent manner, whereas leukocyte accumulation is largely MDA5-dependent. We conclude that airway barrier dysfunction and inflammation are regulated by different mechanisms at early time points after exposure to inhaled dsRNA.
| S-EPMC6505938 | biostudies-literature