Similar Datasets
Project description:Glutamyl-prolyl-tRNA synthetase (EPRS) is a unique bifunctional aminoacyl-tRNA synthetase which catalyzes the ATP-dependent aminoacylation of glutamyl and prolyl residues to cognate tRNAs, constituting fundamental building blocks in protein synthesis. Genomic data suggest that EPRS promotes disease progression and is associated with poor prognosis in multiple myeloma (MM), while downregulation of EPRS triggers MM cell apoptosis implying an amino acid starvation response as a central mechanism. We developed a novel ATP competitive inhibitor, NCP26, targeting the prolyl-tRNA synthetase (PRS) component. The inhibitor demonstrates significant anti-tumor activity against human MM cell lines, regardless of their sensitivity to other therapeutic agents, against patient MM cells and is active in vivo using a MM xenograft mouse model. In contrast to the proline competitive PRS inhibitor halofuginone, NCP26 effects are not altered by exogenous proline levels. NCP26 treatment induces G0/G1 cell cycle arrest followed by apoptotic MM cell death, evidenced by depletion of mitochondrial membrane potential as well as caspase and PARP cleavage. Using combined transcriptomic and proteomic approaches we demonstrate a complex phenotypic response involving multiple pathways in protein quality control which center around the ribosome as integrating hub. Furthermore, we identified multiple proline rich motif containing protein targets of NCP26 as downstream effectors. These include myeloma survival factors such as syndecan 1 (SDC1, CD138), or basic helix-loop-helix transcription factors such as MYC, and transcription factor 3 (TCF3) suggesting that acute blockade of prolyl- aminoacylation evokes a complex pro-apoptotic response beyond the canonical amino acid starvation and integrated stress response. Taken together, our pre-clinical studies validate EPRS as a possible therapeutic target and provide the framework for evaluation of PRS inhibitors in a clinical setting.
2022-09-08 | GSE186445 | GEO
Project description:Glutamyl-prolyl-tRNA synthetase (EPRS) is a unique bifunctional aminoacyl-tRNA synthetase which catalyzes the ATP-dependent aminoacylation of glutamyl and prolyl residues to cognate tRNAs, constituting fundamental building blocks in protein synthesis. Genomic data suggest that EPRS promotes disease progression and is associated with poor prognosis in multiple myeloma (MM), while downregulation of EPRS triggers MM cell apoptosis implying an amino acid starvation response as a central mechanism. We developed a novel ATP competitive inhibitor, NCP26, targeting the prolyl-tRNA synthetase (PRS) component. The inhibitor demonstrates significant anti-tumor activity against human MM cell lines, regardless of their sensitivity to other therapeutic agents, against patient MM cells and is active in vivo using a MM xenograft mouse model. In contrast to the proline competitive PRS inhibitor halofuginone, NCP26 effects are not altered by exogenous proline levels. NCP26 treatment induces G0/G1 cell cycle arrest followed by apoptotic MM cell death, evidenced by depletion of mitochondrial membrane potential as well as caspase and PARP cleavage. Using combined transcriptomic and proteomic approaches we demonstrate a complex phenotypic response involving multiple pathways in protein quality control which center around the ribosome as integrating hub. Furthermore, we identified multiple proline rich motif containing protein targets of NCP26 as downstream effectors. These include myeloma survival factors such as syndecan 1 (SDC1, CD138), or basic helix-loop-helix transcription factors such as MYC, and transcription factor 3 (TCF3) suggesting that acute blockade of prolyl- aminoacylation evokes a complex pro-apoptotic response beyond the canonical amino acid starvation and integrated stress response. Taken together, our pre-clinical studies validate EPRS as a possible therapeutic target and provide the framework for evaluation of PRS inhibitors in a clinical setting.
2022-09-08 | GSE186447 | GEO
Project description:NCP26 is a potent prolyl-tRNA synthetase inhibitor and induces pro- apoptotic responses with in vivo potency in multiple myeloma
| PRJNA773806 | ENA
Project description:NCP26 is a potent prolyl-tRNA synthetase inhibitor and induces pro- apoptotic responses with in vivo potency in multiple myeloma. Bulk RNA-seq data.
| PRJNA773804 | ENA
Project description:Arboviruses represent a group of pathogens that can spread efficiently throughout human populations by hematophagous arthropod vectors. The mosquito-borne (re)emerging Chikungunya and Dengue viruses belong to the alphavirus and flavivirus genus, respectively, with no approved therapeutics or safe vaccines for humans. Transmitted by the same vector Aedes spp., these viruses cause significant morbidity and mortality in endemic areas. Due to the increasing likelihood of co-circulation and co-infection with viruses, we aimed to identify a pharmacologically targetable host factor that can inhibit multiple viruses and show that a potent antagonist of prolyl tRNA synthetase (halofuginone) suppresses both Chikungunya and Dengue viruses. Host tRNA synthetase inhibition may signify an additional approach to combat present and future epidemic pathogens.
| S-EPMC6345585 | biostudies-literature
Project description:NCP26 is a potent prolyl-tRNA synthetase inhibitor and induces pro- apoptotic responses with in vivo potency in multiple myeloma. Single-cell RNA-seq data BM samples.
| PRJNA773807 | ENA
Project description:The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.
| S-EPMC5173487 | biostudies-literature
Project description:To ensure high fidelity in translation, many aminoacyl-tRNA synthetases, enzymes responsible for attaching specific amino acids to cognate tRNAs, require proof-reading mechanisms. Most bacterial prolyl-tRNA synthetases (ProRSs) misactivate alanine and employ a post-transfer editing mechanism to hydrolyze Ala-tRNA(Pro). This reaction occurs in a second catalytic site (INS) that is distinct from the synthetic active site. The 2'-OH of misacylated tRNA(Pro) and several conserved residues in the Escherichia coli ProRS INS domain are directly involved in Ala-tRNA(Pro) deacylation. Although mutation of the strictly conserved lysine 279 (K279) results in nearly complete loss of post-transfer editing activity, this residue does not directly participate in Ala-tRNA(Pro) hydrolysis. We hypothesized that the role of K279 is to bind the phosphate backbone of the acceptor stem of misacylated tRNA(Pro) and position it in the editing active site. To test this hypothesis, we carried out pKa, charge neutralization, and free-energy of binding calculations. Site-directed mutagenesis and kinetic studies were performed to verify the computational results. The calculations revealed a considerably higher pKa of K279 compared to an isolated lysine and showed that the protonated state of K279 is stabilized by the neighboring acidic residue. However, substitution of this acidic residue with a positively charged residue leads to a significant increase in Ala-tRNA(Pro) hydrolysis, suggesting that enhancement in positive charge density in the vicinity of K279 favors tRNA binding. A charge-swapping experiment and free energy of binding calculations support the conclusion that the positive charge at position 279 is absolutely necessary for tRNA binding in the editing active site.
| S-EPMC3986007 | biostudies-literature
Project description:RationaleIncreased protein synthesis of profibrotic genes is a common feature in cardiac fibrosis and heart failure. Despite this observation, critical factors and molecular mechanisms for translational control of profibrotic genes during cardiac fibrosis remain unclear.ObjectiveTo investigate the role of a bifunctional ARS (aminoacyl-tRNA synthetase), EPRS (glutamyl-prolyl-tRNA synthetase) in translational control of cardiac fibrosis.Methods and resultsResults from reanalyses of multiple publicly available data sets of human and mouse heart failure, demonstrated that EPRS acted as an integrated node among the ARSs in various cardiac pathogenic processes. We confirmed that EPRS was induced at mRNA and protein levels (≈1.5-2.5-fold increase) in failing hearts compared with nonfailing hearts using our cohort of human and mouse heart samples. Genetic knockout of one allele of Eprs globally (Eprs+/-) using CRISPR-Cas9 technology or in a Postn-Cre-dependent manner (Eprsflox/+; PostnMCM/+) strongly reduces cardiac fibrosis (≈50% reduction) in isoproterenol-, transverse aortic constriction-, and myocardial infarction (MI)-induced heart failure mouse models. Inhibition of EPRS using a PRS (prolyl-tRNA synthetase)-specific inhibitor, halofuginone, significantly decreases translation efficiency (TE) of proline-rich collagens in cardiac fibroblasts as well as TGF-β (transforming growth factor-β)-activated myofibroblasts. Overexpression of EPRS increases collagen protein expression in primary cardiac fibroblasts under TGF-β stimulation. Using transcriptome-wide RNA-Seq and polysome profiling-Seq in halofuginone-treated fibroblasts, we identified multiple novel Pro-rich genes in addition to collagens, such as Ltbp2 (latent TGF-β-binding protein 2) and Sulf1 (sulfatase 1), which are translationally regulated by EPRS. SULF1 is highly enriched in human and mouse myofibroblasts. In the primary cardiac fibroblast culture system, siRNA-mediated knockdown of SULF1 attenuates cardiac myofibroblast activation and collagen deposition. Overexpression of SULF1 promotes TGF-β-induced myofibroblast activation and partially antagonizes anti-fibrotic effects of halofuginone treatment.ConclusionsOur results indicate that EPRS preferentially controls translational activation of proline codon rich profibrotic genes in cardiac fibroblasts and augments pathological cardiac remodeling. Graphical Abstract: A graphical abstract is available for this article.
| S-EPMC7484271 | biostudies-literature
Project description:About 1 billion years ago, in a single-celled holozoan ancestor of all animals, a gene fusion of two tRNA synthetases formed the bifunctional enzyme, glutamyl-prolyl-tRNA synthetase (EPRS). We propose here that a confluence of metabolic, biochemical, and environmental factors contributed to the specific fusion of glutamyl- (ERS) and prolyl- (PRS) tRNA synthetases. To test this idea, we developed a mathematical model that centers on the precursor-product relationship of glutamic acid and proline, as well as metabolic constraints on free glutamic acid availability near the time of the fusion event. Our findings indicate that proline content increased in the proteome during the emergence of animals, thereby increasing demand for free proline. Together, these constraints contributed to a marked cellular depletion of glutamic acid and its products, with potentially catastrophic consequences. In response, an ancient organism invented an elegant solution in which genes encoding ERS and PRS fused to form EPRS, forcing coexpression of the two enzymes and preventing lethal dysregulation. The substantial evolutionary advantage of this coregulatory mechanism is evidenced by the persistence of EPRS in nearly all extant animals.
| S-EPMC6295713 | biostudies-literature