Differential microRNA profiles associated with the hydroxyurea-inducible SAR1A gene
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE295109 | GEO | 2025/06/23
REPOSITORIES: GEO
Similar Datasets
Project description:Longstanding observations that fetal hemoglobin (HbF, a2g2) expression is reactivated in postnatal red blood cells (RBCs) during hypoxia or recovery from anemia remain unexplained. We identified the hypoxia inducible factor (HIF) signaling pathway as a direct regulator of HbF expression in a CRISPR/Cas9 genetic screen. In RBC precursors, depletion of the von Hippel–Lindau (VHL) E3 ligase stabilized its ubiquitination target HIF1a to induce g-globin gene transcription. Mechanistically, HIF1a-HIF1bheterodimers bound cognate DNA elements in BGLT3, a long-noncoding RNA gene located 2.7 kb downstream of the tandem g-globin genes. This was followed by recruitment of transcriptional activators, chromatin opening, and increased long-range interactions between the g-globin genes and their upstream enhancer. These effects were recapitulated by hypoxia or inhibition of prolyl hydroxylase domain (PHD) enzymes that target HIF1a for ubiquitination. Our findings link globin gene regulation with canonical hypoxia adaptation, elucidate a mechanism for HbF induction during stress erythropoiesis, and identify a novel therapeutic approach for β-hemoglobinopathies.
2022-07-14 | GSE204899 | GEO
Project description:Longstanding observations that fetal hemoglobin (HbF, a2g2) expression is reactivated in postnatal red blood cells (RBCs) during hypoxia or recovery from anemia remain unexplained. We identified the hypoxia inducible factor (HIF) signaling pathway as a direct regulator of HbF expression in a CRISPR/Cas9 genetic screen. In RBC precursors, depletion of the von Hippel–Lindau (VHL) E3 ligase stabilized its ubiquitination target HIF1a to induce g-globin gene transcription. Mechanistically, HIF1a-HIF1bheterodimers bound cognate DNA elements in BGLT3, a long-noncoding RNA gene located 2.7 kb downstream of the tandem g-globin genes. This was followed by recruitment of transcriptional activators, chromatin opening, and increased long-range interactions between the g-globin genes and their upstream enhancer. These effects were recapitulated by hypoxia or inhibition of prolyl hydroxylase domain (PHD) enzymes that target HIF1a for ubiquitination. Our findings link globin gene regulation with canonical hypoxia adaptation, elucidate a mechanism for HbF induction during stress erythropoiesis, and identify a novel therapeutic approach for β-hemoglobinopathies.
2022-07-14 | GSE204900 | GEO
Project description:Longstanding observations that fetal hemoglobin (HbF, a2g2) expression is reactivated in postnatal red blood cells (RBCs) during hypoxia or recovery from anemia remain unexplained. We identified the hypoxia inducible factor (HIF) signaling pathway as a direct regulator of HbF expression in a CRISPR/Cas9 genetic screen. In RBC precursors, depletion of the von Hippel–Lindau (VHL) E3 ligase stabilized its ubiquitination target HIF1a to induce g-globin gene transcription. Mechanistically, HIF1a-HIF1bheterodimers bound cognate DNA elements in BGLT3, a long-noncoding RNA gene located 2.7 kb downstream of the tandem g-globin genes. This was followed by recruitment of transcriptional activators, chromatin opening, and increased long-range interactions between the g-globin genes and their upstream enhancer. These effects were recapitulated by hypoxia or inhibition of prolyl hydroxylase domain (PHD) enzymes that target HIF1a for ubiquitination. Our findings link globin gene regulation with canonical hypoxia adaptation, elucidate a mechanism for HbF induction during stress erythropoiesis, and identify a novel therapeutic approach for β-hemoglobinopathies.
2022-07-14 | GSE204897 | GEO
Project description:Longstanding observations that fetal hemoglobin (HbF, a2g2) expression is reactivated in postnatal red blood cells (RBCs) during hypoxia or recovery from anemia remain unexplained. We identified the hypoxia inducible factor (HIF) signaling pathway as a direct regulator of HbF expression in a CRISPR/Cas9 genetic screen. In RBC precursors, depletion of the von Hippel–Lindau (VHL) E3 ligase stabilized its ubiquitination target HIF1a to induce g-globin gene transcription. Mechanistically, HIF1a-HIF1bheterodimers bound cognate DNA elements in BGLT3, a long-noncoding RNA gene located 2.7 kb downstream of the tandem g-globin genes. This was followed by recruitment of transcriptional activators, chromatin opening, and increased long-range interactions between the g-globin genes and their upstream enhancer. These effects were recapitulated by hypoxia or inhibition of prolyl hydroxylase domain (PHD) enzymes that target HIF1a for ubiquitination. Our findings link globin gene regulation with canonical hypoxia adaptation, elucidate a mechanism for HbF induction during stress erythropoiesis, and identify a novel therapeutic approach for β-hemoglobinopathies.
2022-07-14 | GSE184459 | GEO
Project description:Hemoglobinopathies, including sickle cell disease and _-thalassemia, are global public health concerns. Induction of fetal-type hemoglobin (HbF) is a promising means to treat these disorders; however, precisely how HbF expression is silenced in adult erythroid cells is not fully understood. Here, we show that the LRF/ZBTB7A transcription factor is a potent repressor of HbF production. LRF inactivation derepresses embryonic/fetal _-globin expression in mouse and human adult erythroid cells. We employed genome-wide analysis of the transcriptome, chromatin accessibility and LRF occupancy sites, and demonstrate that LRF occupies the _-globin loci and maintains nucleosome density necessary for _-globin silencing. LRF confers its repressive activity through a unique NuRD repressor complex independent of BCL11A. Strikingly, human erythroid lines lacking both LRF and BCL11A exhibited almost a complete switch in expression from adult- to fetal-type globin, suggesting that these two factors cumulatively represent the near entirety of _-globin repressive activity in adult erythroid cells. RNA-seq, LRF ChIP-seq and ATAC-seq assays were used to investigtae LRF binding, effect of LRF depletion on transcription and chromatin landscape in mouse and human cells.
2016-01-15 | E-GEOD-74977 | biostudies-arrayexpress
Project description:Sickle cell disease (SCD) results from a point mutation in the β-globin gene forming hemoglobin S (HbS), which polymerizes in deoxygenated erythrocytes, triggering recurrent painful vaso-occlusive crises and chronic hemolytic anemia. Reactivation of fetal Hb (HbF) expression ameliorates these symptoms of SCD. Nuclear factor (erythroid derived-2)–like 2 (Nrf2) is a transcription factor that triggers cytoprotective and antioxidant pathways to limit oxidative damage and inflammation and increases HbF synthesis in CD34+ stem cell–derived erythroid progenitors. We investigated the ability of dimethyl fumarate (DMF), a small-molecule Nrf2 agonist, to activate γ-globin transcription and enhance HbF in tissue culture, murine and primate models. DMF recruited Nrf2 to the γ-globin promoters and the locus control region of the β-globin locus in erythroleukemia cells, elevated HbF in SCD donor–derived erythroid progenitors, and reduced hypoxia-induced sickling. Chronic DMF administration in SCD mice induced HbF and increased Nrf2-dependent genes to detoxify heme and limit inflammation. This improved hematological parameters, reduced plasma-free Hb, and attenuated inflammatory markers. Chronic DMF administration to nonanemic primates increased γ-globin mRNA in BM and HbF protein in red cells. DMF represents a potential therapy for SCD to induce HbF and augment vasoprotection and heme detoxification
2017-11-01 | GSE105035 | GEO
Project description:Differences in the amount of fetal hemoglobin (HbF) that persists into adulthood affect the severity of sickle cell disease and the beta-thalassemia syndromes. Genetic association studies have identified sequence variants in the gene BCL11A that influence HbF levels. Here we examine BCL11A as a potential regulator of HbF expression. The high HbF BCL11A genotype is associated with reduced BCL11A expression. Moreover, abundant expression of full-length forms of BCL11A is developmentally restricted to adult erythroid cells. Down-regulation of BCL11A expression in primary adult erythroid cells leads to robust HbF expression. Consistent with a direct role of BCL11A in globin gene regulation, we find that BCL11A occupies several discrete sites in the beta-globin gene cluster. BCL11A emerges as a therapeutic target for reactivation of HbF in beta-hemoglobin disorders. Expression clone label: FBB (4 different subclones, with 2 arrays each), Control label: MelBirA Experiment Overall Design: Microarray expression analysis from parental control mouse erythroleukemia (MEL) cells containing the BirA enzyme (MelBirA cells) and cells containing tagged versions (FLAG-Biotag) of BCL11A. Two control datasets and eight datasets from four subclones containing tagged BCL11A are included.
2009-01-13 | E-GEOD-13283 | biostudies-arrayexpress
Project description:Genes encoding the human β-like hemoglobin proteins undergo a developmental switch from fetal γ-globin to adult β-globin expression at around the time of birth. β-hemoglobinopathies, such as sickle cell disease and β-thalassemia, result from mutations affecting the adult β-globin gene. The only treatment options currently available carry significant side-effects. Analyses of heritable variations in fetal hemoglobin (HbF) levels have provided evidence that reactivation of the silenced fetal γ-globin genes in adult erythroid cells is a promising therapy. The γ-globin repressor BCL11A has become the major focus with several studies investigating its regulation and function as a first step to inhibiting its expression or activity. However, a second repression mechanism has recently been shown to be mediated by the transcription factor ZBTB7A/LRF, suggesting that understanding the regulation of ZBTB7A may also be useful. Here we show that KLF1 directly drives expression of ZBTB7A in erythroid cells by binding to its proximal promoter. We have also uncovered an erythroid-specific regulation mechanism, leading to the upregulation of a novel ZBTB7A transcript in the erythroid compartment. The demonstration that ZBTB7A, like BCL11A, is a KLF1 target gene also fits with the observation that reduced KLF1 expression or activity is associated with HbF derepression.
2017-04-13 | GSE97671 | GEO
Project description:Differences in the amount of fetal hemoglobin (HbF) that persists into adulthood affect the severity of sickle cell disease and the beta-thalassemia syndromes. Genetic association studies have identified sequence variants in the gene BCL11A that influence HbF levels. Here we examine BCL11A as a potential regulator of HbF expression. The high HbF BCL11A genotype is associated with reduced BCL11A expression. Moreover, abundant expression of full-length forms of BCL11A is developmentally restricted to adult erythroid cells. Down-regulation of BCL11A expression in primary adult erythroid cells leads to robust HbF expression. Consistent with a direct role of BCL11A in globin gene regulation, we find that BCL11A occupies several discrete sites in the beta-globin gene cluster. BCL11A emerges as a therapeutic target for reactivation of HbF in beta-hemoglobin disorders. BCL11A siRNA label: B, NT siRNA label: N Experiment Overall Design: Microarray expression analysis from CD34-derived erythroid progenitors treated with either non-targeting (NT) control siRNAs or BCL11A targeting siRNAs. Six samples from the NT control and six samples from the BCL11A siRNA treatment are included. Cells were harvested on day 7 of erythroid differentiation after introduction of siRNAs on day 0 of the differentiation protocol. Experiment Overall Design: 6 BCL11A siRNA datasets, 6 control (NT) datasets
2009-01-13 | E-GEOD-13284 | biostudies-arrayexpress
Project description:Differences in the amount of fetal hemoglobin (HbF) that persists into adulthood affect the severity of sickle cell disease and the beta-thalassemia syndromes. Genetic association studies have identified sequence variants in the gene BCL11A that influence HbF levels. Here we examine BCL11A as a potential regulator of HbF expression. The high HbF BCL11A genotype is associated with reduced BCL11A expression. Moreover, abundant expression of full-length forms of BCL11A is developmentally restricted to adult erythroid cells. Down-regulation of BCL11A expression in primary adult erythroid cells leads to robust HbF expression. Consistent with a direct role of BCL11A in globin gene regulation, we find that BCL11A occupies several discrete sites in the beta-globin gene cluster. BCL11A emerges as a therapeutic target for reactivation of HbF in beta-hemoglobin disorders. BCL11A siRNA label: B, NT siRNA label: N Keywords: cell type comparsion
2008-12-05 | GSE13284 | GEO