Induction of transient and adaptive vs maladaptive unfolded protein responses of the endoplasmic reticulum in pancreatic beta cells
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PROVIDER: PRJNA799602 | ENA |
REPOSITORIES: ENA
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Project description:We are currently studying how these information-carrying oligosaccharides are involved in cellular stress responses, particularly in human genetic diseases called Congenital Disorders Of Glycosylation in which oligosaccharide assembly is defective. We are interested in endoplasmic stress responses/unfolded protein responses. ER glycans and ER lectins are intimately involved in the folding of ER proteins. Therefore, ER lectins and ER glycosyltransferases may be controlled by these stress responses, to produce and/or recognize key glycans in the stress response. Our model system is the human dermal fibroblast. We have successfully calibrated the ER stress responses in these cells by determining the magnitudes of various stress effects (such as chaperone transcription) with different forms of ER stress. We are also completing a study in which activation the signaling molecules Ire1 and ATF6 are also calibrated. We prepared multiple identical aliquots of RNA from cells stressed under several of these calibrated conditions. Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR): Study of the role of ER stress in the expression of genes for ER transferases and lectins that participate in ER folding and quality control using human skin fibroblasts. The UPR response in these cells has been calibrated using various readouts in response to different stresses: 1) 40 nM L-azetidine-2-carboxylate (AZC) 1 hour, 2) 0.2 mg/ml castanospermine, 24 hours, 3) 2 mM Dithiothreitol (DTT), 20 minutes, 4) 100nm Thapsigargin (TG), 30 minutes, 5) 5 ug/ml tunicamycin, 5 hours, 6) untreated control cells
2011-02-17 | E-GEOD-27349 | biostudies-arrayexpress
Project description:Unfolded protein response (UPR) and endoplasmic reticulum (ER) stress in acromegaly
| PRJNA643979 | ENA
Project description:Acromegaly is a growth hormone (GH) excess pathological condition in humans and is associated with somatic disfigurement and a wide variety of systemic manifestations such as arthritis, neuropathies, carpal tunnel syndrome, reproductive disorders, metabolic disorders, and gastrointestinal complications. Studying the effect of growth hormone (GH) excess at the cellular level could help in understanding the underlying causes of acromegaly complications. In our previous publications, we have shown that excess GH increases DNA damage and impairs DNA repair pathways in somatic cells. In addition, we revealed that excessive GH reduces the number of stem cells and causes premature aging. Exaggerated growth is one of the main features of acromegaly and therefore, in this research, we have focused on protein production and biogenesis in acromegaly and whether excess GH is associated with unfolded protein response (UPR) and endoplasmic reticulum (ER) stress. Acromegaly-associated abnormal growth can be caused by hypertrophy or hyperplasia. Using pathway enrichment analysis of RNA seq data from our Zebrafish Acromegaly Model and Flow Cytometry Analysis, here we show a progressive increase in hepatocyte cell size and enrichment of hypertrophy pathways in the muscle and liver. That was associated with a progressive enrichment of protein production pathways and ribosome biogenesis. Moreover, using GSEA (Gene Set Enrichment Analysis) of acromegaly RNA seq data, here we show that endoplasmic reticulum (ER) stress is an accompanying feature of acromegaly disease. Our model exhibited endoplasmic reticulum (ER) stress in various organs, especially in the brain.
2021-03-04 | GSE153755 | GEO
Project description:The unfolded protein response (UPR) is a cellular defense mechanism against glucose deprivation, a cell condition that occurs in solid tumors. A key feature of the UPR is the activation of the transcription program that allows the cell to cope with endoplasmic reticulum (ER) stress. We used micoarrays to show that the UPR transcription program is disrupted by the antitumor macrocyclic compound versipelostatin (VST) and antidiabetic biguanides metformin, buformin and phenformin, depending on cellular glucose availability. Experiment Overall Design: Total 42 samples were prepared for RNA extraction and hybridization on Affymetrix microarrays. Experiment Overall Design: To induce the UPR, we treated cells (HeLa, HT-29, HT1080, MKN74) for 15 or 18 hours under ER stress conditions by replacing the medium with glucose-free medium or by adding either 2-Deoxy-D-glucose (2DG) or Tunicamycin (TM) to glucose-containing medium. UPR modulators (VST, biguanides or pyrvinium pamoate) were added at various final concentrations immediately after cells were placed in glucose-free medium or just before the chemical stressors were added to glucose-containing culture medium.
2009-06-01 | E-GEOD-13548 | biostudies-arrayexpress
Project description:Ire1 is an endoplasmic reticulum (ER)-located transmembrane protein that triggers the unfolded protein response. I recently noticed that Ire1 is activated not only in response to ER accumulation of unfolded proteins but also alongside diauxic shift in yeast Saccharomyces cerevisiae cells. I thus asked how different the Ire1-target genes upon two distinct scenes, a canonical ER -stressing stimuli and diauxic shift. Thus NGS transcriptome analysis was performed by using IRE1+ and ire1-delta mutant yeast cells under these conditions.
2019-03-01 | E-MTAB-6923 | biostudies-arrayexpress
Project description:We obtained transcriptional profiles of third instar eye imaginal disc nuclei with or without endoplasmic reticulum stress using next generation sequencing (NGS). We employed an isolation of nuclei tagged in specific cell type (INTACT) protocol (Ma and Weake, J. of Vis. Exp., 2014) to label nuclear membranes of GMR-GAL4-expressing cells with EGFP. The experimental group also expressed a mutant allele of the membrane visual protein rhodopsin (Rh-1(G69D)), which is known to cause endoplasmic reticulum stress and initiate Unfolded Protein Response (UPR) signaling. The goal of this study was to characterize the transcriptional changes associated with endoplasmic reticulum stress responses in a commonly used platform, the eye imaginal disc.
2021-09-20 | GSE150058 | GEO
Project description:We are currently studying how these information-carrying oligosaccharides are involved in cellular stress responses, particularly in human genetic diseases called Congenital Disorders Of Glycosylation in which oligosaccharide assembly is defective. We are interested in endoplasmic stress responses/unfolded protein responses. ER glycans and ER lectins are intimately involved in the folding of ER proteins. Therefore, ER lectins and ER glycosyltransferases may be controlled by these stress responses, to produce and/or recognize key glycans in the stress response. Our model system is the human dermal fibroblast. We have successfully calibrated the ER stress responses in these cells by determining the magnitudes of various stress effects (such as chaperone transcription) with different forms of ER stress. We are also completing a study in which activation the signaling molecules Ire1 and ATF6 are also calibrated. We prepared multiple identical aliquots of RNA from cells stressed under several of these calibrated conditions.
2011-02-17 | GSE27349 | GEO
Project description:We set out to determine the role of the IRE1/XBP1 pathway, the most ancient and highly conserved endoplasmic reticulum (ER) stress-sensing pathway of the unfolded protein response (UPR), in Schmid metaphyseal chondrodysplasia (MCDS). RNA derived from hypertrophic zones microdissected from growth plates of wildtype mice, mice lacking XBP1 activity in chondrocytes (Xbp1Cart?Ex2), mice carrying a COL10A1 pN617K mutation (ColXN617K), and compound mutants (C/X) was analyzed by whole genome microarray analysis. 1633 probes were differentially expressed between ColXN617K and wildtype, 215 probes were differentially expressed between Xbp1Cart?Ex2 and wildtype, and 1337 probes were differentially expressed between C/X and wildtype. 885 probes were differentially expressed between ColXN617K and wildtype but not Xbp1Cart?Ex2 and wildtype or C/X and wildtype, thus representing the XBP1-dependent response to hypertrophic chondrocyte ER stress. 688 probes were differentially expressed between ColXN617K and wildtype and between C/X and wildtype but not Xbp1Cart?Ex2 and wildtype, thus representing the XBP1-independent response to hypertrophic chondrocyte ER stress. Results were validated by qPCR. Entire growth plate hypertrophic zones were microdissected from one tibia from each of three 2-week old wildtype mice, three 2-week old mice carrying a COL10A1 p.N617K mutation (ColXN617K), three 2-week old mice lacking XBP1 activity in chondrocytes (Xbp1Cart?Ex2), and three 2-week old mice resulting from a cross between ColXN617K and Xbp1Cart?Ex2 (C/X).
2015-08-21 | E-GEOD-72261 | biostudies-arrayexpress
Project description:In eukaryotic cells, the spatial regulation of protein expression is frequently conferred through the coupling of mRNA localization and the local control of translation. mRNA localization to the endoplasmic reticulum (ER) is a prominent example of such regulation and serves a ubiquitous role in segregating the synthesis of secretory and integral membrane proteins to the ER. Recent genomic and biochemical studies have now expanded this view to suggest a role for the ER in global protein synthesis. We have utilized cell fractionation and ribosome profiling to obtain a genomic survey of the subcellular organization of mRNA translation and report that ribosomal loading of mRNAs, a proxy for mRNA translation, is biased to the ER. Notably, ER-associated mRNAs encoding both cytosolic and topogenic signal-encoding proteins display similar ribosome loading densities, suggesting that ER-associated ribosomes serve a global role in mRNA translation. We propose that the partitioning of mRNAs and their translation between the cytosol and ER compartments may represent a novel mechanism for the post-transcriptional regulation of gene expression. HEK293 cells were fractionated between the cytosol and endoplasmic reticulum. Within each fraction, ribosome footprints were generated and sequenced. In parallel, total mRNA was sequenced.
2011-12-20 | E-GEOD-31539 | biostudies-arrayexpress
Project description:Endoplasmic reticulum-associated degradation (ERAD) represents a principle quality control (QC) mechanism to clear misfolded proteins in the ER; however, its physiological significance and the nature of endogenous ERAD substrates remain largely unknown. Here we discover that IRE1alpha, the sensor of unfolded protein response (UPR), is a bona fide substrate of the Sel1L-Hrd1 ERAD complex. Mechanistically, ERAD-mediated IRE1alpha degradation occurs in a Bip-dependent manner under basal conditions and is attenuated in response to ER stress. Both intramembrane hydrophilic residues of IRE1alpha and lectin protein OS9 are required for IRE1alpha degradation. ERAD deficiency causes IRE1alpha protein stabilization, accumulation and mild activation both in vitro and in vivo, leading to cellular hypersensitivity to ER stress and inflammation. Furthermore, though enterocyte-specific Sel1L-knockout mice (Sel1LÎ?IEC) are viable and appear normal, they are more susceptible to experimental colitis in an IRE1alpha-dependent but CHOP-independent manner. Collectively, these results demonstrate that Sel1L-Hrd1 ERAD serves a distinct, essential function in restraint of IRE1alpha signaling in vivo by managing its protein turnover. Colon epithelium of wild type and enterocyte-specific Sel1L knockout mice were subjected to gene expression analysis.
2015-11-04 | E-GEOD-70563 | biostudies-arrayexpress