Reduced Treg suppressive function and HIF-1α expression in hypoxia
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE41999 | GEO | 2013/12/31
SECONDARY ACCESSION(S): PRJNA178720
REPOSITORIES: GEO
Similar Datasets
Project description:Recently, hypoxia via the transcription factor HIF-1a has been implicated to play an important role for the fate of the adaptive immune response by regulatory T cells (Treg) and T helper 17 cells (TH17) in the mouse model. However, the reports on the effect of HIF-1a are conflicting and so far no functional data in the human system are available. Therefore, we analyzed the effect of hypoxia and HIF-1a on Treg and TH17 in the human system. FACS, western blot and reporter assays clearly demonstrated that hypoxia does not up-regulate the level of HIF-1a in CD4+ T cells (THC) and microarray analysis revealed no change of the transcriptome comparing normoxia vs. hypoxia. Furthermore, we could show that HIF-1a is almost exclusively regulated via NF-kB and NFAT, whereas hydroxylation and subsequent degradation of HIF-1a had little to no effect. In addition, we showed that HIF-1a is essential for nTreg mediated suppression and for IL-17A secretion of TH17, but not for TH17 lineage commitment measured by RORγt expression. In conclusion, our results demonstrated that THC have a distinct regulation of HIF-1a protein levels, which was absolutely essential for Treg and TH17 function. 3 patients, 2 cell type, 2 treatments = 12 arrays
2013-12-31 | E-GEOD-41999 | biostudies-arrayexpress
Project description:This a model from the article:
Hypoxia-dependent sequestration of an oxygen sensor by a widespread structural motif can shape the hypoxic response - a predictive kinetic model
Bernhard Schmierer, Béla Novák1 and Christopher J Schofield
BMC Systems Biology2010, 4:139
20955552,
Abstract:
Background
The activity of the heterodimeric transcription factor hypoxia inducible factor (HIF) is regulated by the post-translational, oxygen-dependent hydroxylation of its α-subunit by members of the prolyl hydroxylase domain (PHD or EGLN)-family and by factor inhibiting HIF (FIH). PHD-dependent hydroxylation targets HIFα for rapid proteasomal degradation; FIH-catalysed asparaginyl-hydroxylation of the C-terminal transactivation domain (CAD) of HIFα suppresses the CAD-dependent subset of the extensive transcriptional responses induced by HIF. FIH can also hydroxylate ankyrin-repeat domain (ARD) proteins, a large group of proteins which are functionally unrelated but share common structural features. Competition by ARD proteins for FIH is hypothesised to affect FIH activity towards HIFα; however the extent of this competition and its effect on the HIF-dependent hypoxic response are unknown.
Results
To analyse if and in which way the FIH/ARD protein interaction affects HIF-activity, we created a rate equation model. Our model predicts that an oxygen-regulated sequestration of FIH by ARD proteins significantly shapes the input/output characteristics of the HIF system. The FIH/ARD protein interaction is predicted to create an oxygen threshold for HIFα CAD-hydroxylation and to significantly sharpen the signal/response curves, which not only focuses HIFα CAD-hydroxylation into a defined range of oxygen tensions, but also makes the response ultrasensitive to varying oxygen tensions. Our model further suggests that the hydroxylation status of the ARD protein pool can encode the strength and the duration of a hypoxic episode, which may allow cells to memorise these features for a certain time period after reoxygenation.
Conclusions
The FIH/ARD protein interaction has the potential to contribute to oxygen-range finding, can sensitise the response to changes in oxygen levels, and can provide a memory of the strength and the duration of a hypoxic episode. These emergent properties are predicted to significantly shape the characteristics of HIF activity in animal cells. We argue that the FIH/ARD interaction should be taken into account in studies of the effect of pharmacological inhibition of the HIF-hydroxylases and propose that the interaction of a signalling sensor with a large group of proteins might be a general mechanism for the regulation of signalling pathways.
There are there models described in the paper. 1) Skeleton Model 1 (SKM1) - HIFα CAD-hydroxylation in the absence of the FIH/AR-interaction. 2) Skeleton Model 2 (SKM2) - FIG sequestration by ARD proteins and oxygen-dependent FIH-release. 3) Full Model (Fusion of SKM1 and SKM2) - the effects of the FIH/ARD proteins interaction on HIFα CAD-hydroxylation.
This model corresponds to the "Full Model" described in the paper. The model reproduces figure 5 of the publication.
This model originates from BioModels Database: A Database of Annotated Published Models (http://www.ebi.ac.uk/biomodels/). It is copyright (c) 2005-2011 The BioModels.net Team.
For more information see the terms of use.
To cite BioModels Database, please use: Li C, Donizelli M, Rodriguez N, Dharuri H, Endler L, Chelliah V, Li L, He E, Henry A, Stefan MI, Snoep JL, Hucka M, Le Novère N, Laibe C (2010) BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models. BMC Syst Biol., 4:92.
2010-08-17 | BIOMD0000000300 | BioModels
Project description:Th17 cells are potent mediators in autoimmune diseases and RORγt is required for their development. Recent studies have shown that RORγt+ Treg cells in the gut regulate intestinal inflammation by inhibiting effector T cell function. In the current study, we report that RORγt+ Treg cells were also found in lymph nodes following immunization. Not only distinct from intestinal RORγt+ Treg in their transcriptomes, peripheral RORγt+ Treg cells were derived from Foxp3+ thymic Treg cells, in an antigen-specific manner. Development of these RORγt+ Treg cells, coined as T regulatory 17 (Tr17) cells, depended on IL-6/Stat3 signaling. Tr17 cells showed suppressive activity against antigen-specific effector T cells in vitro. In addition, Tr17 cells efficiently inhibited myelin-specific Th17 cell-mediated CNS auto-inflammation in a passive EAE model. Collectively, our study demonstrates Tr17 cells as effector Treg cells that potentially restrict autoimmunity.
2017-08-31 | GSE103319 | GEO
Project description:The asparagine hydroxylase, factor inhibiting HIF (FIH) confers oxygen-dependence upon the hypoxia-inducible factor (HIF), a master regulator of the cellular adaptive response to hypoxia. Studies investigating whether asparagine hydroxylation is a general regulatory oxygen-dependent modification have identified multiple non-HIF targets for FIH. However the functional consequences of this outside of the HIF pathway remain unclear. Here, we demonstrate that the deubiquitinase ovarian tumor domain containing, ubiquitin aldehyde binding protein 1 (OTUB1) is a substrate for hydroxylation by endogenous FIH on N22. Mutation of N22 leads to a profound change in the interaction of OTUB1 with proteins important in cellular metabolism. Furthermore, mutant OTUB1 (lacking the hydroxylation site) impairs cellular metabolic processes when compared to wild type. Based on these data, we hypothesize that OTUB1 is a target for functional hydroxylation by FIH, and propose that this provides new insight into the regulation of cellular energy metabolism during hypoxia.
2017-03-28 | MSV000080695 | MassIVE
Project description:Although hypoxia inducible factor-1a (HIF-1a) was originally identified as a transcriptional factor to adapt hypoxia, HIF-1a has also been shown to regulate metabolic pathways specific for cancer, including aerobic glycolysis, namely “Warburg effect”. However, the mechanisms by which HIF-1a mediates the metabolic pathway under normoxia are not fully understood. Here, we identified gamma-glutamylcyclotransferase (GGCT) as a novel regulator of HIF-1a. GGCT is a highly expressed protein in various cancer tissues. Knockdown of GGCT exerts anticancer effects both in vitro and in vivo; thus, it is considered a promising therapeutic target. In this study, we show that depleting GGCT downregulates the protein and mRNA expressions of HIF-1a in PC3 prostate cancer cells, and that overexpressing GGCT upregulates them in mouse fibroblast NIH3T3 cells. We also show that depleting GGCT downregulates HIF-1a downstream target genes involved in glycolysis, whereas overexpressing GGCT exhibits upregulation pattern in these genes. Furthermore, we suggest that GGCT induces the metabolic switch from citric acid cycle to glycolysis under normoxia. Additionally, we show that GGCT regulates expression of HIF-1a protein via AMPK-mTORC1-4EBP1 pathway in PC3 cells. These results indicate the GGCT plays a regulatory role in the expression of HIF-1a followed by glycolytic switch in cancer cells.
2020-07-17 | GSE154592 | GEO
Project description:Although hypoxia inducible factor-1a (HIF-1a) was originally identified as a transcriptional factor to adapt hypoxia, HIF-1a has also been shown to regulate metabolic pathways specific for cancer, including aerobic glycolysis, namely “Warburg effect”. However, the mechanisms by which HIF-1a mediates the metabolic pathway under normoxia are not fully understood. Here, we identified gamma-glutamylcyclotransferase (GGCT) as a novel regulator of HIF-1a. GGCT is a highly expressed protein in various cancer tissues. Knockdown of GGCT exerts anticancer effects both in vitro and in vivo; thus, it is considered a promising therapeutic target. In this study, we show that depleting GGCT downregulates the protein and mRNA expressions of HIF-1a in PC3 prostate cancer cells, and that overexpressing GGCT upregulates them in mouse fibroblast NIH3T3 cells. We also show that depleting GGCT downregulates HIF-1a downstream target genes involved in glycolysis, whereas overexpressing GGCT exhibits upregulation pattern in these genes. Furthermore, we suggest that GGCT induces the metabolic switch from citric acid cycle to glycolysis under normoxia. Additionally, we show that GGCT regulates expression of HIF-1a protein via AMPK-mTORC1-4EBP1 pathway in PC3 cells. These results indicate the GGCT plays a regulatory role in the expression of HIF-1a followed by glycolytic switch in cancer cells.
2020-07-17 | GSE154584 | GEO
Project description:HIF-1A and HIF-2A regulate both overlapping and unique target genes in response to hypoxia. In this dataset, we identify specific HIF-1A and HIF-2A target genes in glioblastoma cells. 12 samples were analysed comprising 4 experimental conditions (normoxia scr, hypoxia scr, hypoxia siHIF1, hypoxia siHIF2) in triplicate. We made pairwise comparisons between the averages of each triplicate set to normoxia scr using the Partek suite.
2012-02-25 | E-GEOD-27523 | biostudies-arrayexpress
Project description:The hypoxia inducible factor (HIF) system orchestrates cellular responses to hypoxia in animals. HIF is an /-heterodimeric transcription factor that regulates the expression of hundreds of genes in a context dependent manner. A hypoxia-sensing component of the HIF system involves oxygen-dependent catalysis by the HIF hydroxylases; in humans there are three HIF prolyl hydroxylases (PHD1-3) and an asparaginyl hydroxylase (FIH). PHD catalysis regulates HIF levels and FIH catalysis regulates HIF activity. How differences in HIF hydroxylation status relate to variations in the induction of HIF target gene transcription is unknown. We report studies using small molecule inhibitors of the HIF hydroxylases to investigate the extent to which HIF target gene upregulation is induced by reduced PHD catalysis. The results reveal substantial differences in the role of prolyl- and asparaginyl-hydroxylation in regulating hypoxia responsive genes in cells. Selective PHD inhibitors with different structural scaffolds behave similarly. However, under the tested conditions, a broad-spectrum 2OG dioxygenase inhibitor is a better mimic of the transcriptional response to hypoxia than the selective PHD inhibitors, consistent with an important role for FIH in the hypoxic transcriptional response. Indeed, combined application of selective PHD and FIH inhibitors resulted in transcriptional induction of a subset of genes that were not fully responsive to PHD inhibition alone. Thus, for the therapeutic regulation of HIF target genes, it is important to consider both PHD and FIH activity, and in the case of some sets of target genes, simultaneous inhibition of the PHDs and FIH catalysis may be preferable.
2016-10-25 | E-MTAB-4264 | biostudies-arrayexpress
Project description:HIF-1A and HIF-2A regulate both overlapping and unique target genes in response to hypoxia. In this dataset, we identify specific HIF-1A and HIF-2A target genes in glioblastoma cells.
2012-02-25 | GSE27523 | GEO
Project description:HIF-1a activates genes under hypoxia and was hypothesized to regulate bone regeneration. Surprisingly, HET HIF-1a fracture calluses are larger, stronger and stiffer than WT HIF-1a calluses due to decreased apoptosis. These data identify apoptosis inhibition as a means to enhance bone regeneration. Introduction: Bone regeneration subsequent to fracture involves the synergistic activation of multiple signaling pathways. Localized hypoxia following fracture activates hypoxia-inducible factor 1 alpha (HIF-1a) leading to increased expression of HIF-1 target genes. We therefore hypothesized that HIF-1a is a key regulator of bone regeneration Materials and Methods: Fixed femoral fractures were generated in mice with partial HIF-1a deficiency (HET HIF-1a) and wild type littermates (WT HIF-1a). Fracture calluses and intact contralateral femurs from post fracture day (PFD) 21 and 28 (N=5-10) were subjected to MicroCT evaluation and 4-point bending in order to assess morphometric and mechanical properties. Molecular analyses were carried out on PFD 7, 10 and 14 samples (N=3) to determine differential gene expression at both mRNA and protein levels. Finally, TUNEL staining was performed on PFD 14 samples (N=2) to elucidate differential apoptosis. Results: Surprisingly, fracture calluses from HET HIF-1a mice exhibit greater mineralization and are larger, stronger and stiffer. Microarray analyses focused on hypoxia-induced genes revealed differential expression (between genotypes) of several genes associated with the apoptotic pathway. Real-time PCR confirmed these results, demonstrating higher expression of pro-apoptotic PP2A and lower expression of anti-apoptotic BCL2 in WT HIF-1a calluses. Subsequent TUNEL staining demonstrates that WT HIF-1a calluses contain larger numbers of TUNEL positive chondrocytes and osteoblasts than HET HIF-1a calluses. Conclusions: We conclude that partial HIF-1a deficiency results in decreased chondrocytic and osteoblastic apoptosis; thereby allowing the development of larger, stiffer calluses and enhancing bone regeneration. Furthermore, apoptosis inhibition may be a promising target for developing new treatments to accelerate bone regeneration. Keywords: Bone, Fracture, Apoptosis, Hypoxia, Microarray
2007-01-12 | GSE6091 | GEO