NR4A1 and NR4A3 Restrict HSC Proliferation via Reciprocal Regulation of C/EBPα and Inflammatory Signaling
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE100990 | GEO | 2018/01/23
REPOSITORIES: GEO
Similar Datasets
Project description:Members of the NR4A subfamily of nuclear receptors have complex, overlapping roles during hematopoietic cell development and also function as tumor suppressors of hematologic malignancies. We previously identified NR4A1 and NR4A3 (NR4A1/3) as functionally redundant suppressors of acute myeloid leukemia (AML) development. However, their role in hematopoietic stem cell (HSC) homeostasis remains to be disclosed. Using a conditional Nr4a1/Nr4a3 knockout mouse (CDKO), we show that codepletion of NR4A1/3 promotes acute changes in HSC homeostasis including loss of HSC quiescence, accumulation of oxidative stress, and DNA damage while maintaining stem cell regenerative and differentiation capacity. Molecular profiling of CDKO HSCs revealed widespread upregulation of genetic programs governing cell cycle and inflammation and an aberrant activation of the interferon and NF-κB signaling pathways in the absence of stimuli. Mechanistically, we demonstrate that NR4A1/3 restrict HSC proliferation in part through activation of a C/EBPα-driven antiproliferative network by directly binding to a hematopoietic-specific Cebpa enhancer and activating Cebpa transcription. In addition, NR4A1/3 occupy the regulatory regions of NF-κB-regulated inflammatory cytokines, antagonizing the activation of NF-κB signaling. Taken together, our results reveal a novel coordinate control of HSC quiescence by NR4A1/3 through direct activation of C/EBPα and suppression of activation of NF-κB-driven proliferative inflammatory responses.
| S-EPMC5863701 | biostudies-literature
Project description:Loss of functional beta-cell mass is a hallmark of Type 1 and Type 2 diabetes, and methods for restoring these cells are needed. Nkx6.1 induces beta-cell proliferation, but the pathway by which Nkx6.1 activates beta-cell expansion has not been defined. Here we demonstrate that Nkx6.1 induces expression of the Nr4a1 and Nr4a3 orphan nuclear receptors, and that these factors are both necessary and sufficient for Nkx6.1-mediated β-cell proliferation. Overexpression of the Nr4a receptors results in increased expression of key cell cycle inducers E2F1 and cyclin E1. Furthermore, Nr4a receptors induce components of the anaphase-promoting complex, including Ube2c. We set up a microarray using primary rat islets that were left untreated or transduced with adenoviruses overexpressing GFP, Nr4a1 or Nr4a3 for 48 h.
2014-02-18 | E-GEOD-55078 | biostudies-arrayexpress
Project description:Loss of functional beta-cell mass is a hallmark of Type 1 and Type 2 diabetes, and methods for restoring these cells are needed. We have previously reported that overexpression of the homeodomain transcription factor Nkx6.1 in rat pancreatic islets induces beta-cell proliferation and enhances glucose-stimulated insulin secretion, but the pathway by which Nkx6.1 activates beta-cell expansion has not been defined. Here we demonstrate that Nkx6.1 induces expression of the Nr4a1 and Nr4a3 orphan nuclear receptors, and that these factors are both necessary and sufficient for Nkx6.1-mediated beta-cell proliferation. Consistent with this finding, global knockout of Nr4a1 results in a decrease in beta-cell area in neonatal and young mice. Overexpression of Nkx6.1 and the Nr4a receptors results in increased expression of key cell cycle inducers E2F1 and cyclin E1. Furthermore, Nkx6.1 and Nr4a receptors induce components of the anaphase-promoting complex, including Ube2c, resulting in degradation of the cell cycle inhibitor p21CIP1. These studies identify a new bipartite pathway for activation of beta-cell proliferation, suggesting several new targets for expansion of functional beta-cell mass. We set up a microarray using primary rat islets that were left untreated or transduced with adenoviruses overexpressing betagal or Nkx6.1 for 48 h.
2014-02-18 | E-GEOD-55077 | biostudies-arrayexpress
Project description:Loss of functional β-cell mass is a hallmark of Type 1 and Type 2 diabetes, and methods for restoring these cells are needed. We have previously reported that overexpression of the homeodomain transcription factor Nkx6.1 in rat pancreatic islets induces β-cell proliferation and enhances glucose-stimulated insulin secretion, but the pathway by which Nkx6.1 activates β-cell expansion has not been defined. Here we demonstrate that Nkx6.1 induces expression of the Nr4a1 and Nr4a3 orphan nuclear receptors, and that these factors are both necessary and sufficient for Nkx6.1-mediated β-cell proliferation. Consistent with this finding, global knockout of Nr4a1 results in a decrease in β-cell area in neonatal and young mice. Overexpression of Nkx6.1 and the Nr4a receptors results in increased expression of key cell cycle inducers E2F1 and cyclin E1. Furthermore, Nkx6.1 and Nr4a receptors induce components of the anaphase-promoting complex, including Ube2c, resulting in degradation of the cell cycle inhibitor p21CIP1. These studies identify a new bipartite pathway for activation of β-cell proliferation, suggesting several new targets for expansion of functional β-cell mass.
2014-02-18 | GSE55077 | GEO
Project description:Loss of functional β-cell mass is a hallmark of Type 1 and Type 2 diabetes, and methods for restoring these cells are needed. Nkx6.1 induces β-cell proliferation, but the pathway by which Nkx6.1 activates β-cell expansion has not been defined. Here we demonstrate that Nkx6.1 induces expression of the Nr4a1 and Nr4a3 orphan nuclear receptors, and that these factors are both necessary and sufficient for Nkx6.1-mediated β-cell proliferation. Overexpression of the Nr4a receptors results in increased expression of key cell cycle inducers E2F1 and cyclin E1. Furthermore, Nr4a receptors induce components of the anaphase-promoting complex, including Ube2c.
2014-02-18 | GSE55078 | GEO
Project description:We have revealed that Nr4a family nuclear orphan receptors broadly regulate a transcriptional program in Treg cells. In this study, to give an insight into Nr4a-mediated regulation of the transcriptional program in Treg cells, we performed ChIP-seq experiment using anti-Nr4a1 antibodies and a chromatin lysate from Treg cells. Examination of Nr4a1 binding sites in mouse Treg cells.
2015-06-30 | E-GEOD-70417 | biostudies-arrayexpress
Project description:Hematopoietic stem cells (HSCs) sustain life-long hematopoiesis and emerge during mid-gestation from hemogenic endothelial (HE) progenitors via an endothelial to hematopoietic transition (EHT). The full scope of molecular mechanisms governing this process remains unclear. The NR4A subfamily of orphan nuclear receptors act as tumour suppressors in myeloid leukemogenesis and have never been implicated in HSC specification. Here, we report that Nr4a1 and Nr4a2 expression is upregulated in hemogenic endothelium during EHT. Progressive genetic ablation of Nr4a gene dosage results in a gradual decrease in numbers of nascent c-Kit+ hematopoietic progenitors in developing embryos, c-Kit+ cell cluster size in the dorsal aorta, and a block in HSC maturation, revealed by an accumulation of pro-HSCs and pre-HSC-type I cells and decreased numbers of pre-HSC-type II cells. Consistent with these observations, cells isolated from E11.5 Nr4a1-/-; Nr4a2-/- aorta-gonads-mesonephros (AGM) are devoid of in vivo long-term hematopoietic repopulating potential. Molecularly, employing spatial transcriptomic analysis we determined that the genetic ablation of Nr4a1 and Nr4a2 prevents NOTCH signaling from being downregulated in intra-aortic clusters and thus for pro-HSCs to mature into HSCs. Interestingly, this defect is partially rescued via ex vivo culture of dissected AGMs with SCF, IL3 and FLT3L, which may bypass NOTCH-dependent regulation. Overall, our data reveal a novel role for the NR4A family of orphan nuclear receptors in EHT.
2024-11-04 | GSE281058 | GEO
Project description:NR4As are critical tumor suppressors of acute myeloid leukemia (AML) whose expression is broadly silenced in leukemia initiating cell enriched populations from human patients relative to normal hematopoietic stem/progenitor cells. Rescued NR4A expression in human AML cells inhibits proliferation and reprograms AML gene signatures via transcriptional mechanisms that remain to be elucidated. By intersecting an acutely regulated, NR4A1 dependent transcriptional profile with genome wide NR4A binding distribution, we now identify an NR4A targetome of 685 genes that are directly regulated by NR4A1. We show that NR4As regulate gene transcription primarily through interaction with distal enhancers that are co-enriched for both NR4A1 and ETS transcription factor motifs. Using a subset of NR4A activated genes, we demonstrate that the ETS factors ERG and FLI-1 are required for activation of NR4A bound enhancers and NR4A target gene induction. NR4A1 dependent recruitment of ERG and FLI-1 promotes binding of p300 histone acetyl transferase to activate NR4A bound enhancers. These findings disclose novel epigenetic mechanisms by which NR4As and ETS factors cooperate to drive NR4A dependent gene transcription in human AML cells. NR4A1 ChIP-seq after exogenous NR4A1 expression
2016-03-22 | E-GEOD-79491 | biostudies-arrayexpress
Project description:NR4As are critical tumor suppressors of acute myeloid leukemia (AML) whose expression is broadly silenced in leukemia initiating cell enriched populations from human patients relative to normal hematopoietic stem/progenitor cells. Rescued NR4A expression in human AML cells inhibits proliferation and reprograms AML gene signatures via transcriptional mechanisms that remain to be elucidated. By intersecting an acutely regulated, NR4A1 dependent transcriptional profile with genome wide NR4A binding distribution, we now identify an NR4A targetome of 685 genes that are directly regulated by NR4A1. We show that NR4As regulate gene transcription primarily through interaction with distal enhancers that are co-enriched for both NR4A1 and ETS transcription factor motifs. Using a subset of NR4A activated genes, we demonstrate that the ETS factors ERG and FLI-1 are required for activation of NR4A bound enhancers and NR4A target gene induction. NR4A1 dependent recruitment of ERG and FLI-1 promotes binding of p300 histone acetyl transferase to activate NR4A bound enhancers. These findings disclose novel epigenetic mechanisms by which NR4As and ETS factors cooperate to drive NR4A dependent gene transcription in human AML cells. Transcriptome analysis in triplicate 6hr after exogenous NR4A1 expression compared to GFP transfection control.
2016-03-22 | E-GEOD-79490 | biostudies-arrayexpress
Project description:The NR4A family of nuclear receptors are upregulated by acute and chronic antigen stimulation, and play redundant, tolerogenic roles in T and B cells. To bypass their obligate function in the Treg lineage, we generated competitive chimeras with Nr4a1-/-Nr4a3-/- (double knockout or DKO) bone marrow mixed with congenically marked WT bone marrow at a 1:5 ratio. As a result of a defect in Treg production by DKO cells, Treg in mixed chimeras are almost exclusively of WT origin. By contrast, we generate an approximately 1:1 DKO:WT ratio in the peripheral T cell compartment because DKO cells escape negative selection. After reconstitution, we observed pronounced accumulation of anergic DKO CD4 T cells, but a defect in functional tolerance resulting in autoantibody production. Based on these studies and published literature, we hypothesize that the NR4A family regulate TCR-induced transcripts in both naive and anergic CD4 T cells. To identify such targets, we sorted naive and anergic CD4 T cells of either WT or DKO genotype (CD45.1+ or CD45.1-) on the basis of CD73/FR4/CD44 expression from these chimeras directly into RLT buffer. In parallel, we stimulated sorted naive CD4 T cells of each genotype in vitro with plate-bound anti-CD3 and anti-CD28 stimulation for 3 hrs and then generated RLT lysates. We made biological triplicate samples of each condition (naive WT and DKO, naive stimulated WT and DKO, anergic WT and DKO) resulting in 6 different populations x 3 replicates = 18 samples. Samples were subjected to library prep and bulk RNA sequencing to identify DEG.
2021-06-24 | GSE178782 | GEO