RELA knockdown on gene expression in KG1α leukemia cells upon DNA damage
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE147530 | GEO | 2022/04/12
REPOSITORIES: GEO
Similar Datasets
Project description:Protein deamidation is emerging as a post-translational modification that regulates protein function. The general role of protein deamidation is emerging asn fundamental to biological processes, yet remains is poorly understood. Here, we report that the rate-limiting enzyme of pyrimidine synthesis, a trifunctional enzyme containing activity of carbamoyl phosphate synthetase, aspartyl transcarbamoylase and dihydroorotase (CAD), deamidates the RelA subunit to inactivate NF-κB and promote glycolysis. Functional screening and identified CAD as a negative regulator of NF-κB activation, and biochemical analysis demonstrated that CAD deamidatesd RelA in vitro and in cellsto negate NF-κB activation. D eamidated RelA, though failed to activate the expression of NF-κB-dependent genes, thoughbut it up-regulated that of key glycolytic enzymes to promote glycolysis and cell proliferation. In proliferating cells, CAD is activated and catalyzes de novo pyrimidine synthesis to meet the metabolic need during S phase. CAD-mediated RelA deamidation and NF-κB inactivation and glycolytic gene expression paralleled in a cell cycle-dependent mannerdriven by CAD-mediated RelA deamidation are necessary for cell proliferation. In addition, CAD promoted glycolysis via deamidated RelA that up-regulated the expression of key glycolytic enzymes. Stratification of cancer cell lines by CAD-mediated RelA deamidation predicted their sensitivity to inhibitors of glycolytic enzymes, while a subset of mutations predisposed RelA to deamidation and promoted glycolysis to enable cell proliferation. This work describes a process of metabolic reprogramming enabled by CAD-mediated RelA deamidation that underpins cell proliferation and tumorigenesis.
2019-11-01 | GSE132871 | GEO
Project description:By binding to specific DNA elements, known collectively as “κB sites”, contained within the promoters/enhancers of target genes, NF-κB regulates gene expression. We found that the identity of the central base pair (bp) of κB sites profoundly impacts the transcriptional activity of NF-κB dimers. RelA dimers prefer an A/T bp at this position for optimum transcriptional activation (A/T-centric) and discriminate against G/C-centric κB sites. The p52 homodimer, in contrast, activates transcription from G/C-centric κB sites in complex with Bcl3 but represses transcription from the A/T-centric sites. The p52:Bcl3 complex binds to these two classes of κB sites in distinct modes permitting recruitment of coactivator, corepressor, or both coactivator and corepressor complexes in promoters containing G/C, A/T or both G/C and A/T-centric sites. Therefore, through sensing of bp differences within κB sites, NF-κB dimers modulate biological programs by activating, repressing and altering expression of effector genes. Total RNA extracted from bone marrow derived macrophages (BMDMs) with Bcl3 siRNA knockdown or mouse scramble siRNA knockdown were subjected to LPS stimulation.
2012-08-06 | E-GEOD-39922 | biostudies-arrayexpress
Project description:Background: Lymphotoxin signaling via the lymphotoxin-β receptor (LTβR) has been implicated in several biological processes, ranging from development of secondary lymphoid organs, maintenance of splenic tissue, host defense against pathogens, autoimmunity, and lipid homeostasis. The major transcription factor that is activated by LTβR crosslinking is NF-κB. Two signaling pathways have been described that result in the activation of classical p50-RelA and alternative p52-RelB NF-κB heterodimers. Results: Using microarray analysis, we investigated the transcriptional response downstream of the LTβR in mouse embryoni fibroblasts (MEF) and its regulation by the RelA and RelB subunits of NF-κB. We describe novel LTβR-responsive genes that are regulated by RelA and/or RelB. Interestingly, we found that the majority of LTβR-regulated genes require the presence of both RelA and RelB, suggesting significant crosstalk between the two NF-κB activation pathways. Gene Ontology (GO) analysis confirmed that LTβR-NF-κB target genes are predominantly involved in the regulation of immune responses. However, other biological processes, such as apoptosis/cell death, cell cycle, angiogenesis, and taxis were also regulated by LTβR signaling. Moreover, we show that activation of the LTβR inhibits the expression of a key adipogenic transcription factor, peroxisome proliferator activated receptor-γ (pparg), suggesting that LTβR signaling may interfere with adipogenic differentiation. Conclusions: Thus, microarray analysis of LTβR-stimulated fibroblasts revealed further insight into the transcriptional response of LTβR signaling and its regulation by the NF-κB family members RelA and RelB. Keywords: cell type comparison (wt vs relA-/- vs relB-/-) after genetic modification using a time course for each cell type (wt, relA-/-, relB-/-) two time points were analysed (0h as control and 10h) using 3 technical replicates resulting in 18 samples in total
2008-12-17 | E-GEOD-11963 | biostudies-arrayexpress
Project description:TNFα has an evolutionary conserved role in mediating inflammation via activation of the transcription factor NF-κB. The functions of individual NF-κB binding sites are not well understood. To identify conserved and functionally important NF-κB binding sites in mammals, we performed ChIP-seq to map the genome-wide binding of RELA and select histone modifications in primary vascular endothelial cells (ECs) isolated from the aortas of human (HAEC), mouse (MAEC) and cow (BAEC), before and after TNFα. The conserved RELA binding sites show strong epigenetic changes in response to TNFα and enrich near genes controlling vascular development and pro-inflammatory responses. Our method identifies novel modes of RELA-chromatin interactions that are conserved in mammals and shared between multiple cell-types. Particularly, genomic regions bound by RELA prior to stimulation are important responders during TNFα stimulation. We use CRISPR/Cas9 genome editing to validate the roles of the conserved RELA pre-bound sites near pro-inflammatory genes such as CCL2 and PLK2. Our evolutionary approach describes new aspects of mammalian NF-κB biology including its role within super-enhancers and relevance in inflammatory disorders.
2020-10-03 | E-MTAB-7889 | biostudies-arrayexpress
Project description:Post-translational modification of NF-κB subunits provides a mechanism to differentially regulate their activity in response to the many stimuli that can induce this pathway. However, the physiological significance of these modifications is largely unknown and it remains unclear if these have a critical role in the normal and pathological functions of NF-κB in vivo. Among these, phosphorylation of the RelA(p65) Thr505 residue has been described as an important regulator of NF-κB activity in cell lines but its physiological significance was not known. Therefore, to learn more about the role of this pathway in vivo, we generated a knockin mouse with a RelA T505A mutation. Unlike RelA knockout mice, the RelA T505A mice develop normally but exhibit aberrant hepatocyte proliferation following liver partial hepatectomy or damage resulting from carbon tetrachloride treatment. Consistent with these effects, RelA T505A mice exhibit earlier onset of cancer in the N-nitrosodiethylamine (DEN) model of hepatocellular carcinoma. This data reveals a critical pathway controlling NF-κB function in the liver that acts to suppress tumour-promoting activities of RelA.
2015-11-30 | E-MTAB-3596 | biostudies-arrayexpress
Project description:Protein deamidation is emerging as a post-translational modification that regulates protein function. The general role of protein deamidation is emerging asn fundamental to biological processes, yet remains is poorly understood. Here, we report that the rate-limiting enzyme of pyrimidine synthesis, a trifunctional enzyme containing activity of carbamoyl phosphate synthetase, aspartyl transcarbamoylase and dihydroorotase (CAD), deamidates the RelA subunit to inactivate NF-κB and promote glycolysis. Functional screening and identified CAD as a negative regulator of NF-κB activation, and biochemical analysis demonstrated that CAD deamidatesd RelA in vitro and in cellsto negate NF-κB activation. D eamidated RelA, though failed to activate the expression of NF-κB-dependent genes, thoughbut it up-regulated that of key glycolytic enzymes to promote glycolysis and cell proliferation. In proliferating cells, CAD is activated and catalyzes de novo pyrimidine synthesis to meet the metabolic need during S phase. CAD-mediated RelA deamidation and NF-κB inactivation and glycolytic gene expression paralleled in a cell cycle-dependent mannerdriven by CAD-mediated RelA deamidation are necessary for cell proliferation. In addition, CAD promoted glycolysis via deamidated RelA that up-regulated the expression of key glycolytic enzymes. Stratification of cancer cell lines by CAD-mediated RelA deamidation predicted their sensitivity to inhibitors of glycolytic enzymes, while a subset of mutations predisposed RelA to deamidation and promoted glycolysis to enable cell proliferation. This work describes a process of metabolic reprogramming enabled by CAD-mediated RelA deamidation that underpins cell proliferation and tumorigenesis.
2019-11-01 | GSE132868 | GEO
Project description:By binding to specific DNA elements, known collectively as “κB sites”, contained within the promoters/enhancers of target genes, NF-κB regulates gene expression. We found that the identity of the central base pair (bp) of κB sites profoundly impacts the transcriptional activity of NF-κB dimers. RelA dimers prefer an A/T bp at this position for optimum transcriptional activation (A/T-centric) and discriminate against G/C-centric κB sites. The p52 homodimer, in contrast, activates transcription from G/C-centric κB sites in complex with Bcl3 but represses transcription from the A/T-centric sites. The p52:Bcl3 complex binds to these two classes of κB sites in distinct modes permitting recruitment of coactivator, corepressor, or both coactivator and corepressor complexes in promoters containing G/C, A/T or both G/C and A/T-centric sites. Therefore, through sensing of bp differences within κB sites, NF-κB dimers modulate biological programs by activating, repressing and altering expression of effector genes.
2012-08-07 | GSE39922 | GEO
Project description:Background: Lymphotoxin signaling via the lymphotoxin-β receptor (LTβR) has been implicated in several biological processes, ranging from development of secondary lymphoid organs, maintenance of splenic tissue, host defense against pathogens, autoimmunity, and lipid homeostasis. The major transcription factor that is activated by LTβR crosslinking is NF-κB. Two signaling pathways have been described that result in the activation of classical p50-RelA and alternative p52-RelB NF-κB heterodimers. Results: Using microarray analysis, we investigated the transcriptional response downstream of the LTβR in mouse embryoni fibroblasts (MEF) and its regulation by the RelA and RelB subunits of NF-κB. We describe novel LTβR-responsive genes that are regulated by RelA and/or RelB. Interestingly, we found that the majority of LTβR-regulated genes require the presence of both RelA and RelB, suggesting significant crosstalk between the two NF-κB activation pathways. Gene Ontology (GO) analysis confirmed that LTβR-NF-κB target genes are predominantly involved in the regulation of immune responses. However, other biological processes, such as apoptosis/cell death, cell cycle, angiogenesis, and taxis were also regulated by LTβR signaling. Moreover, we show that activation of the LTβR inhibits the expression of a key adipogenic transcription factor, peroxisome proliferator activated receptor-γ (pparg), suggesting that LTβR signaling may interfere with adipogenic differentiation. Conclusions: Thus, microarray analysis of LTβR-stimulated fibroblasts revealed further insight into the transcriptional response of LTβR signaling and its regulation by the NF-κB family members RelA and RelB. Keywords: cell type comparison (wt vs relA-/- vs relB-/-) after genetic modification using a time course
2008-12-18 | GSE11963 | GEO
Project description:Using a mouse model with hepatocyte-specific deletion of transcription factor NF-κB RelA (p65), our group has previously revealed the important role of RelA in inducing the acute phase response, maintaining host defense, and preventing liver injury during sepsis. To goal of this study was determine the influence of RelA on hepatic gene changes that provide liver protection during infection. Mice were generated with functional deletion of NF-kappaB RelA (p56) in hepatocytes using a Cre-LoxP system. Mutant mice expressed Cre-recombinase under the transcriptional control of an albumin promotor and homozygous floxed RelA alleles. Wild type control mice lack the Cre-recombinase. Microarray analysis was performed on liver RNA collected from both genotypes of mice in the absence and presence of pneumococcal bacteremia.
2019-06-07 | GSE126642 | GEO
Project description:Different types of DNA damage can initiate phosphorylation-mediated signalling cascades that result in stimulus specific pro- or anti-apoptotic cellular responses. Amongst its many roles, the NF-κB transcription factor RelA is central to the DNA damage response pathway. Yet, understanding of the co-ordinated signalling mechanisms that result in these different DNA damaging agents inducing specific cellular outcomes through RelA remains unclear. Here, we examine the temporal effects of exposure of U2OS cells to either etoposide (ETO) or hydroxyurea (HU) on the phosphorylation status of RelA and its protein binding partners, using label-free quantitative phosphoproteomics. Although there were relatively few stimulus specific differences overall in the phosphorylated RelA interactome in response to either DNA damaging agent, we observed subtle, but significant changes in the phosphorylation states of the RelA bound proteins as a function of both the type of and duration of the DNA damaging agent used. The DNA double strand break (DSB) inducing ETO invoked more rapid, sustained responses than HU, with regulated targets primarily involved in transcription, cell division and (unsurprisingly) DSB repair. Kinase substrate prediction of confident, differentially regulated phosphosites suggests possible roles for CDK1 and MAPK3/ERK1 signaling, in addition to the known roles of ATM/ATR. In contrast, HU-induced replicative stress mediated more temporally dynamic regulation, with phosphoprotein components of the RelA network having known roles in rRNA/mRNA processing and translational initiation, many of which contained a 14-3-3ε binding motif. Our data thus point to differential regulation of key cellular processes and the involvement of unique signalling pathways in modulating DNA damage-specific functions of RelA.
2021-09-09 | PXD019589 | Pride