Identify differentially expressed genes related to the neurodegenerative process in a new animal model of hepatic encephalopathy (HE).
Cerebellar neurodegeneration in a new rat model of episodic hepatic encephalopathy.
Specimen part, Treatment
View SamplesCyclin D3 is critical hematopoiesis and loss of cyclin D3 leads to resistance to transformation of bone marrow progenitors by Notch1-IC.
Therapeutic targeting of the cyclin D3:CDK4/6 complex in T cell leukemia.
Specimen part, Cell line
View SamplesActivated NOTCH1 induces T-ALL in mice when transduced in bone marrow (BM) cells. T-ALL cells activate the calcineurin/NFAT pathway in vivo (Medyouf H. et al. Nat Med 2007 [PMID 17515895]).
Leukemia-initiating cell activity requires calcineurin in T-cell acute lymphoblastic leukemia.
Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Stress-independent activation of XBP1s and/or ATF6 reveals three functionally diverse ER proteostasis environments.
Specimen part, Treatment
View SamplesThe unfolded protein response (UPR) maintains endoplasmic reticulum (ER) proteostasis through the activation of transcription factors such as XBP1s and ATF6. The functional consequences of these transcription factors for ER proteostasis remain poorly defined. Here, we describe methodology that enables orthogonal, small molecule-mediated activation of the UPR-associated transcription factors XBP1s and/or ATF6 in the same cell independent of stress. We employ transcriptomics and quantitative proteomics to evaluate ER proteostasis network remodeling owing to the XBP1s and/or ATF6 transcriptional programs. Furthermore, we demonstrate that the three ER proteostasis environments accessible by activating XBP1s and/or ATF6 differentially influence the folding, trafficking, and degradation of destabilized ER client proteins without globally affecting the endogenous proteome. Our data reveal how the ER proteostasis network is remodeled by the XBP1s and/or ATF6 transcriptional programs at the molecular level and demonstrate the potential for selectively restoring aberrant ER proteostasis of pathologic, destabilized proteins through arm-selective UPR-activation.
Stress-independent activation of XBP1s and/or ATF6 reveals three functionally diverse ER proteostasis environments.
Specimen part, Treatment
View SamplesThe unfolded protein response (UPR) maintains endoplasmic reticulum (ER) proteostasis through the activation of transcription factors such as XBP1s and ATF6. The functional consequences of these transcription factors for ER proteostasis remain poorly defined. Here, we describe methodology that enables orthogonal, small molecule-mediated activation of the UPR-associated transcription factors XBP1s and/or ATF6 in the same cell independent of stress. We employ transcriptomics and quantitative proteomics to evaluate ER proteostasis network remodeling owing to the XBP1s and/or ATF6 transcriptional programs. Furthermore, we demonstrate that the three ER proteostasis environments accessible by activating XBP1s and/or ATF6 differentially influence the folding, trafficking, and degradation of destabilized ER client proteins without globally affecting the endogenous proteome. Our data reveal how the ER proteostasis network is remodeled by the XBP1s and/or ATF6 transcriptional programs at the molecular level and demonstrate the potential for selectively restoring aberrant ER proteostasis of pathologic, destabilized proteins through arm-selective UPR-activation.
Stress-independent activation of XBP1s and/or ATF6 reveals three functionally diverse ER proteostasis environments.
Specimen part, Treatment
View SamplesDnmt2 genes are highly conserved tRNA methyltransferases with biological roles in cellular stress responses. Dnmt2 has recently been implicated in transposon silencing in Drosophila but the exact molecular mechanisms are unclear. Adult Dnmt2 mutants were heat shocked and RNA sequencing was performed on visible high-molecular weight RNAs to determine the identity of up-regulated transposons. Dnmt2 mutants accumulated almost all families of transposons after heat shock, indicating a general mis-regulation of transposon silencing in Dnmt2 mutants during the stress response. Overall design: one sample, excised, electroeluted and pooled RNA of different molecular weight, Dnmt2 mutant during recovery from a single heat shock
Mutations in Cytosine-5 tRNA Methyltransferases Impact Mobile Element Expression and Genome Stability at Specific DNA Repeats.
Sex, Specimen part, Cell line, Subject
View SamplesBACKGROUND & AIMS: Inflammatory Bowel Disease (IBD) is a chronic inflammatory condition driven by loss of homeostasis between the mucosal immune system, the commensal gut microbiota, and the intestinal epithelium. Our overarching goal is to understand how these components of the intestinal ecosystem cooperate to control homeostasis and to identify novel signal transduction pathways that become dysregulated in IBD. METHODS: We have applied a multi-scale systems biology approach to a mouse model of chronic colitis. We combined quantitative measures of epithelial hyperplasia and immune infiltration with multivariate analysis of inter- and intra-cellular signaling molecules in order to generate a tissue level model of the inflamed disease state. We utilized the computational model to identify signaling pathways that were dysregulated in the context of colitis and then validated model predictions by measuring the effect of small molecule pathway inhibitors on colitis. RESULTS: Our data-driven computational model identified mTOR signaling as a potential driver of inflammation and mTOR inhibition reversed the molecular, immunological, and epithelial manifestations of colitis. Inhibition of Notch signaling, which induces epithelial differentiation, had the same effect, suggesting that the epithelial proliferation/differentiation state plays a key role in maintaining homeostasis of the colon. Confirming this, we found that colonic organoids grown ex vivo showed a similar relationship between proliferation and cytokine expression, even in the absence of gut bacteria and immune cells. CONCLUSIONS: Our study provides a tissue-level systems biology perspective of murine colitis and suggests that mTOR plays a key role in regulating colonic homeostasis by controlling epithelial proliferation/differentiation state.
The colonic epithelium plays an active role in promoting colitis by shaping the tissue cytokine profile.
Specimen part
View SamplesThe unfolded protein response (UPR), as its name implies, safeguards secretory pathway proteostasis. The most ancient arm of the UPR, the IRE1-activated, XBP1s-mediated transcriptional response, has roles in secretory pathway maturation beyond resolving proteostatic stress. Understanding the consequences of XBP1s' transcriptional output for cellular processes is critical for elucidating mechanistic connections between XBP1s and development, immunity, and disease. Here, we show that a key functional consequence of XBP1s activation is a cell type-dependent shift in the distribution of N-glycan structures on endogenous membrane and secreted proteomes. XBP1s activity decreases sialylation of tri- and tetra-antennary N-glycans in the HEK293 membrane proteome and secretome, while substantially increasing the population of high mannose N-glycans only in the secretome. Related, but distinctive, signatures in the HEK293 N-glycome are observed when the entire UPR is activated in a stress-dependent manner using thapsigargin. In HeLa cells, stress-independent XBP1s activation increases the population of cell surface high mannose N-glycans and tetra-antennary N-glycans. mRNA profiling experiments suggest that the XBP1s-mediated remodeling of the N-glycome may re-flect a coordinated consequence of transcriptional resculpting of the N-glycan maturation pathway by XBP1s. The discovery of XBP1s-induced N-glycan structural remodeling on a glycome-wide scale suggests that XBP1s is a master regulator of N-glycan maturation. Moreover, because the sugars on cell surface proteins or on those proteins secreted from an XBP1s-activated cell can be molecularly distinct from those of an unactivated cell, these findings reveal a potential new mechanism for translating intracellular stress signaling pathways into al-tered interactions with the extracellular environment. Overall design: Three biological replicates of HeLaXBP1s cells treated with DMSO vehicle, 1 ug/ml dox or 750 nM Thapsigargin.
XBP1s activation can globally remodel N-glycan structure distribution patterns.
Cell line, Treatment, Subject, Time
View SamplesBackground: Gene expression profiling has shown its ability to identify with high accuracy low cytogenetic risk acute myeloid leukemia such as acute promyelocytic leukemia and leukemias with t(8;21) or inv(16). The aim of this gene expression profiling study was to evaluate to what extent suboptimal samples with low leukemic blast load (range, 2-59%) and/or poor quality control criteria could also be correctly identified. Methods: Specific signatures were first defined so that all 71 acute promyelocytic leukemia, leukemia with t(8;21) or inv(16)-AML as well as cytogenetically normal acute myeloid leukemia samples with at least 60% blasts and good quality control criteria were correctly classified (training set). The classifiers were then evaluated for their ability to assign to the expected class 111 samples considered as suboptimal because of a low leukemic blast load (n=101) and/or poor quality control criteria (n=10) (test set). Results: With 10-marker classifiers, all training set samples as well as 97 of the 101 test samples with a low blast load, and all 10 samples with poor quality control criteria were correctly classified. Regarding test set samples, the overall error rate of the class prediction was below 4 percent, even though the leukemic blast load was as low as 2%. Sensitivity, specificity, negative and positive predictive values of the class assignments ranged from 91% to 100%. Of note, for acute promyelocytic leukemia and leukemias with t(8;21) or inv(16), the confidence level of the class assignment was influenced by the leukemic blast load. Conclusion: Gene expression profiling and a supervised method requiring 10-marker classifiers enable the identification of favorable cytogenetic risk acute myeloid leukemia even when samples contain low leukemic blast loads or display poor quality control criterion.
Routine use of microarray-based gene expression profiling to identify patients with low cytogenetic risk acute myeloid leukemia: accurate results can be obtained even with suboptimal samples.
Time
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