Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Molecular effects of ISRIB during asparagine deprivation

ABSTRACT: The integrated stress response (ISR) is a conserved pathway which is activated by cells that are exposed to stress. In lung adenocarcinoma (LUAD), activation of the ATF4 branch of the ISR by particular oncogenic mutations has been linked to the regulation of amino acid metabolism. In the present study, we provide evidence for ATF4 activation across multiple stages and molecular subtypes of human LUAD. In response to extracellular amino acid limitation, LUAD cells with diverse genotypes broadly induce ATF4 in an eIF2α dependent manner, which can be blocked pharmacologically using the integrated stress response inhibitor (ISRIB). Although suppressing eIF2α or ATF4 can trigger different biological consequences, adaptive cell cycle progression and cell migration are particularly sensitive to inhibition of the ISR. These phenotypes specifically require the ATF4 target gene asparagine synthetase (ASNS), which maintains protein translation independently of the mTOR/PI3K pathway. Moreover, NRF2 protein levels and oxidative stress can be modulated by the ISR downstream of ASNS. Finally, we demonstrate that the ISR via ASNS controls the biosynthesis of select proteins, including the cell cycle regulator cyclin B1, which are associated with poor LUAD patient prognosis. Our findings uncover new regulatory layers of the ISR pathway and its control of proteostasis in lung cancer cells as they adapt to metabolic barriers during tumor progression.

ORGANISM(S): Homo sapiens

PROVIDER: GSE126232 | GEO | 2019/10/23

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

The Small Molecule ISRIB Reverses the Effects of eIF2α Phosphorylation on Translation and Stress Granule Assembly

Project description:We recently identified ISRIB as a potent inhibitor of the integrated stress response (ISR). ISRIB renders cells resistant to the effects of eIF2α phosphorylation and enhances long-term memory in rodents (10.7554/eLife.00498). Here we show by genome-wide in vivo ribosome profiling that translation of a restricted subset of mRNAs is induced upon ISR activation. ISRIB substantially reversed the translational effects elicited by phosphorylation of eIF2α and induced no major changes in translation or mRNA levels in unstressed cells. eIF2α phosphorylation-induced stress granule (SG) formation was blocked by ISRIB. Strikingly, ISRIB addition to stressed cells with pre-formed SGs induced their rapid disassembly, liberating mRNAs into the actively translating pool. Restoration of mRNA translation and modulation of SG dynamics may be an effective treatment of neurodegenerative diseases characterized by eIF2α phosphorylation, SG formation and cognitive loss. Ribosome profiling with paired RNA-seq

2015-02-27 | E-GEOD-65778 | biostudies-arrayexpress

The integrated stress response is tumorigenic and constitutes a therapeutic liability in KRAS-driven lung cancer.

Project description:The integrated stress response (ISR) is an essential stress-support pathway increasingly recognized as a determinant of tumorigenesis. Here we demonstrate that ISR is pivotal in lung adenocarcinoma (LUAD) development, the most common histological type of lung cancer and a leading cause of cancer death worldwide. Increased phosphorylation of the translation initiation factor eIF2 (p-eIF2α), the focal point of ISR, is related to invasiveness, increased growth, and poor outcome in 928 LUAD patients. Dissection of ISR mechanisms in KRAS-driven lung tumorigenesis in mice demonstrated that p-eIF2α causes specific translational repression of dual specificity phosphatase 6 (DUSP6), resulting in increased phosphorylation of the extracellular signal-regulated kinase (p-ERK). Treatments with ISR inhibitors, including a memory-enhancing drug with limited toxicity, provides a novel therapeutic option for KRAS-driven lung cancer insofar as they substantially reduce tumor growth and prolong mouse survival. Our data provide a novel rationale for the implementation of ISR-based regimens in LUAD treatment.

2021-05-25 | GSE155238 | GEO

N6-Methyladenosine Guides mRNA Alternative Translation during Integrated Stress Response

Project description:The integrated stress response (ISR) facilitates cellular adaptation to a variety of stress conditions via phosphorylation of the common target eIF2α. During ISR, the translation of certain stress-related mRNAs is upregulated in spite of global suppression of protein synthesis.The selective translation often relieson alternative mechanisms, such as leaky scanning or reinitiation, but the underlying mechanism remains incompletely understood. Here we report that,in response to amino acid starvation, the reinitiation of ATF4 is not only governed by eIF2α-controlled ternary complex availability, but is also subjected to regulation by mRNA methylation in the form of N6-methyladenosine (m6A). We demonstrate that m6A in the 5' untranslated region (5’ UTR) controls ribosome scanning and subsequent start codonselection. Global profiling of initiating ribosomes reveals widespread alternative translation events influenced by mRNA methylation. Consistently, Fto-transgenic mice manifest enhanced ATF4 expression, highlighting the critical role of 5’ UTR methylation in translational regulation of ISR at cellular and organismal levels.

2017-08-15 | GSE102659 | GEO

The Small Molecule ISRIB Reverses the Effects of eIF2α Phosphorylation on Translation and Stress Granule Assembly

2015-02-27 | GSE65778 | GEO

Genome wide binding of ATF4 and CEBPG bZIP transcription factors in MEFs under amino acid deprived (AAD) conditions

Project description:The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances and ER stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here we show that C/EBPÎ³:ATF4 heterodimers, but not C/EBPÎ²:ATF4 dimers, are the predominant CARE binding species in stressed cells. C/EBPÎ³ and ATF4 associate with genomic CAREs in a mutually-dependent manner and co-regulate many ISR genes. By contrast, the C/EBP family members C/EBPÎ² and CHOP were largely dispensable for induction of stress genes. Cebpgâ/â MEFs proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpgâ/â mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBPÎ³-deficient newborns die from atelectasis and respiratory failure which can be mitigated by in utero exposure to the anti-oxidant, N-acetyl-cysteine. Cebpgâ/â mice on a mixed strain background show improved viability but, upon aging, develop significantly fewer malignant solid tumors compared to WT animals. Our findings identify C/EBPÎ³ as a novel anti-oxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells. Evaluation of genomic binding of 2 bZIP transcription factors under amino acid deprivation conditions in mouse embryonic fibroblasts

2015-11-19 | E-GEOD-75165 | biostudies-arrayexpress

Microarray expression data of NCI-H1975 cells treated with osimertinib, alpelisib, or combination of these in the presence or absence of L-histidinol.

Project description:Oncogenic signals often activate abnormal proliferation, while simultaneously activate stress-adaptive mechanisms such as the integrated stress response (ISR) to ensure rapid growth under intrinsic and extrinsic stress conditions. In this study, we investigated the involvement of EGFR-PI3K pathway in the regulation of ISR in EGFR-mutant NSCLC cell lines under amino acid deprivation. We found that the third generation EGFR inhibitor osiemrtinib suppressed induction of activation transcription factor 4 (ATF4), the key ISR effector, in EGFR mutant cells, while the effect was to a less extent in cells harboring PIK3CA-co-alteration. PI3K inhibitors including P110a-specific inhibitor alpelicib markedly suppress ATF4 induction in PIK3CA-mutant cell lines. To further explore the role of EGFR-PI3K, transcriptome analysis was performed in EGFR- and PIK3CA-mutated NCI-H1975 cells treated with osimertinib, alpelisib, or combination of these in the absence or presence of histidyl-tRNA inhibitor L-histidinol (His), mimicking amino acid deprived conditions. Among His-induced genes, either osimertinib or alpelisib partially, but the combination dramatically suppressed a cluster of genes targeted by ATF4. Furthermore, combination of osimertinib and alpelisib increased apoptotic cells under amino acid deprived conditions. These results indicate that oncogenic EGFR-PI3K pathway contributes to cellular adaptation to stress conditions through ATF4. We used microarrays to identify genes whose expression is up- or down-regulated by inhibition of EGFR, PI3K, or both under amino acid deprivation.

2023-03-22 | GSE216508 | GEO

Examination of gene expression in cerebellum of mouse strains B6J, B6J-nmf205-/-, B6J-Gcn2-/- and B6J-nmf205-/-;Gcn2-/-.

Project description:Ribosome stalling during translation has recently been shown to cause neurodegeneration, yet the signaling pathways triggered by stalled elongation complexes are unknown. To investigate these pathways we analyzed the brain of B6J-nmf205-/- mice in which neuronal elongation complexes are stalled at AGA codons due to deficiencies in a tRNA Arg(UCU) tRNA and GTPBP2, a mammalian ribosome rescue factor. Increased levels of phosphorylation of eIF2α (Ser51) were detected prior to neurodegeneration in these mice and transcriptome analysis demonstrated activation of ATF4, a key transcription factor in the integrated stress response (ISR) pathway. Genetic experiments showed that this pathway was activated by the eIF2α kinase, GCN2, in an apparent deacylated tRNA-independent fashion. Further we found that the ISR attenuates neurodegeneration in B6J-nmf205-/- mice, underscoring the importance of cellular and stress context on the outcome of activation of this pathway. These results demonstrate the critical interplay between translation elongation and initiation in regulating neuron survival during cellular stress.

2016-06-15 | GSE79929 | GEO

Examination of gene expression in cerebellum and hippocampus for mouse C57BL/6J WT and nmf205-/-

2016-06-15 | GSE79926 | GEO

RNA-Seq experiment to identify genes regulated by ATF4

Project description:Activating Transcription Factor 4 (ATF4) is a transcription factor induced by the integrated stress response (ISR). This experiment is a genome-wide profiling of ATF4-dependent RNA expression in human HAP-1 cells. HAP-1 is a near-haploid human cell line that was derived from KBM-7 cells isolated from a patient with Chronic Myelogenous Leukemia. We analyzed WT and ATF4 KO cells. We induced ATF4 expression by mimicking amino acid starvation with the drug histidinol. RNA expression profiles were generated for WT and ATF4 KO HAP1 cells. ATF4 genes were mutated using Cas9 genome editing technology. Amino acid starvation was mimicked by treating WT and ATF4 KO cells with 2 mM histidinol for 24 hours, which increases ATF4 expression.

2015-08-28 | E-GEOD-69308 | biostudies-arrayexpress

Genome-wide analysis of ATF4 binding in histidinol-treated cells

Project description:Activating Transcription Factor 4 (ATF4) is a transcription factor induced by the integrated stress response (ISR). This experiment is a genome-wide occupancy profiling of ATF4 in human HAP1 cells. HAP1 is a near-haploid human cell line that was derived from KBM-7 cells isolated from a patient with Chronic Myelogenous Leukemia. We induced ATF4 expression by mimicking amino acid starvation with the drug histidinol. We identified peaks of ATF4 binding using three independent antibodies. Examination of ATF4 binding in HAP1 cells treated with 2 mM histidinol for 24 hours.

2015-08-28 | E-GEOD-69304 | biostudies-arrayexpress

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data