Ontology highlight
ABSTRACT:
PROVIDER: PRJNA960629 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR24263527_1.fastq.gz | Fastqsanger.gz | |||
| SRR24263527_2.fastq.gz | Fastqsanger.gz | |||
| SRR24263528_1.fastq.gz | Fastqsanger.gz | |||
| SRR24263528_2.fastq.gz | Fastqsanger.gz | |||
| SRR24263529_1.fastq.gz | Fastqsanger.gz |
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Similar Datasets
Project description:Therapeutic base editing of HBG promoter to reactivate high level of gamma-globin expression with no detectable off-target mutations
| PRJNA1013694 | ENA
Project description:CRISPR-Cas base editors are preferred tool for genome editing as they generate desired editing without any double strand break in the genome, as double stand break is detrimental to the cells. In our study we have demonstrated the significance of base editors in editing the highly homologous HBG promoter (HBG1 and HBG2) region to introduce novel HPFH-like mutation to elevate HbF for therapeutical applications. Previous studies revealed that the base editors can cause unintended Cas-independent edits at transcriptome level. To validate off-target at RNA level, we performed a transcriptome wide analysis. The frequency of unintended edits in the HUDEP-2 stable cell lines expressing the base editors with the gRNA were not significant compared to the control. We determined the ABE mediated A to I conversion and CBE mediated C to U conversion across the base edited samples. The RNA off-target analysis was carried out with the help of REDItools v 2 tool. This data suggests that despite high on-target editing in DNA, the Cas-independent RNA off-target were not at detectable range compared to control. The differential expression of 34 selected genes which necessitate globin regulation were compared between the unedited HUDEP WT, CBE control, ABE control, and edited ABE (with gRNA 2/11) and edited CBE (with gRNA 2/11). We observed that there is no significant differential gene expression between the edited and control cells except the gamma and delta globin genes. These results suggest that base editors are preferred tools to edit highly homologous HBG promoter region to created HPFH-like mutations inducing HbF levels without causing double strand breaks, larger deletions and no significant RNA off-targets which are detrimental to the gene edited cells.
2022-01-02 | GSE192801 | GEO
Project description:Genetic manipulations to increase fetal hemoglobin (HbF, α2γ2) in postnatal red blood cells (RBCs) can alleviate β-thalassemia and sickle cell disease. We compared five strategies in CD34+ hematopoietic stem and progenitor cells, using either Cas9 nuclease, which creates uncontrolled indel mixtures, or adenine base editors (ABE), which generate more precise nucleotide changes. The most potent modification was ABE generation of γ-globin (HBG1/HBG2) −175 A>G, which creates a promoter binding motif for the transcriptional activator TAL1. In erythroid colonies with >87.5% on-target edits, those with −175 A>G expressed 81 ± 7% HbF, versus 17 ± 11% in unedited controls. In comparison, HbF levels were lower and more variable in erythroid cells modified with either of two Cas9 nuclease strategies with similar editing efficiencies, being 32 ± 19% when a BCL11A repressor binding motif in the γ-globin promoter was targeted and 52 ± 13% when the +58 BCL11A erythroid enhancer was targeted. Contrary to currently accepted models of γ-globin regulation, HbF levels varied significantly with different Cas9 indels that disrupted the γ-globin promoter BCL11A binding motif. The −175 A>G base edit also induced HbF more potently than did the Cas9 nuclease approaches in RBCs generated after transplantation of modified normal or SCD patient CD34+ cells into mice. Our data suggest a strategy for potent, uniform induction of HbF and provide insights into γ-globin gene regulation. More generally, we demonstrate that diverse indels generated by Cas9 nuclease can cause unexpected variations in biological outcomes that can be circumvented by base editing, with important implications for therapeutic gene editing efforts.
2023-04-28 | GSE228819 | GEO
Project description:Human genetics has validated de-repression of fetal gamma globin (HBG) in adult erythroblasts as a powerful therapeutic paradigm in diseases involving defective adult beta globin (HBB)1. To identify novel factors involved in the switch from HBG to HBB expression, we performed Assay for Transposase Accessible Chromatin with high-throughput sequencing (ATAC-seq)2 on discrete sorted erythroblast populations derived from bone marrow (BM) or cord blood (CB) progenitors, representing adult and fetal states, respectively. Comparison of the ATAC-seq profiles revealed enrichment of NFI DNA binding motifs and increased chromatin accessibility at the NFIX promoter in BM populations relative to CB populations, suggesting that NFIX may repress HBG. NFIX knockdown in BM cells increased HBG mRNA and fetal hemoglobin (HbF) protein levels, coincident with increased chromatin accessibility and decreased DNA methylation at the HBG promoter. Conversely, overexpression of NFIX in CB cells reduced HbF levels. Identification of NFIX as a novel target for HbF activation has potential implications in the development of therapeutics for hemoglobinopathies.
2023-05-31 | GSE196731 | GEO
Project description:Human genetics has validated de-repression of fetal gamma globin (HBG) in adult erythroblasts as a powerful therapeutic paradigm in diseases involving defective adult beta globin (HBB)1. To identify factors involved in the switch from HBG to HBB expression, we performed Assay for Transposase Accessible Chromatin with high-throughput sequencing (ATAC-seq)2 on sorted erythroid lineage cells derived from bone marrow (BM) or cord blood (CB), representing adult and fetal states, respectively. BM to CB cell ATAC-seq profile comparisons revealed genome-wide enrichment of NFI DNA binding motifs and increased NFIX promoter chromatin accessibility, suggesting that NFIX may repress HBG. NFIX knockdown in BM cells increased HBG mRNA and fetal hemoglobin (HbF) protein levels, coincident with increased chromatin accessibility and decreased DNA methylation at the HBG promoter. Conversely, overexpression of NFIX in CB cells reduced HbF levels. Identification and validation of NFIX as a new target for HbF activation has implications in the development of therapeutics for hemoglobinopathies.
2023-06-07 | GSE234155 | GEO
Project description:We have identified putative repressor region (PRR) to exon-1 of β-globin (βE1) in the β-globin cluster as a core region in alll the HPFH deletions that activates fetal hemoglobin and silences adult hemoglobin. To test the impact of PRR-βE1 gene editing in β-globin cluster configuration, we employed Circular chromosome conformation capture (4C) analysis to assess the LCR interaction to the gamma-globin promoter. Using HBG2 promoter as viewpoint,4C analysis showed an increased interaction of HBG promoter to the hypersensitive (HS) sites of the LCR in HUDEP-2 clones harbouring PRR-βE1 biallelic deletions compared to control HUDEP-2 cells. Link for 4C output files Mendeley - Venkatesan, Vigneshwaran (2022), “4C data set ”, Mendeley Data, V1, doi: 10.17632/cz3thnr9kf.1
2022-04-26 | GSE201388 | GEO
Project description:Human fetal γ-globin gene is developmentally silenced around the birth, and reactivation of γ-globin gene in adulthood sheds new light on ameliorating symptoms of hemoglobin disorders, such as sickle cell disease (SCD) and β-thalassemias. However, the precise regulation process of γ-globin remains incompletely understood. Here, we found that a new protein directly interacted with SOX6 and exerted a significant repression effect on the expression of γ-globin gene in erythroid cells. Further studies have demonstrated that it bound directly to γ-globin gene promoter via octamer binding motif, which in turn suppressed the transcriptional activity of γ-globin gene promoter. Thus, these data indicate that this new protein acts as a novel transcriptional repressor in the regulation of γ-globin gene expression through direct promoter binding, implying a potential alternative therapeutic target for the treatment of SCD and β-thalassemias.
2022-02-16 | PXD024259 | Pride
Project description:BCL11A, the major regulator of HbF(α2γ2) level, represses γ-globin expression through direct promoter binding in adult erythroid cells in a switch to adult adult-type HbA (α2β2) production. Yet, the mechanism remains unclear. To uncover how BCL11A initiates repression, we used CRISPR/Cas9 and dCas9 screens to dissect the γ-globin promoters and identified an apparent activator element near the BCL11A binding region. Using CUT&RUN and base editing approaches, we demonstrate that this element, the proximal CCAAT box, is the binding site of transcription activator NF-Y. BCL11A competes with NF-Y binding through steric hindrance to initiate γ-globin repression, and the distance between the two motifs is critical for direct competition. Occupancy of NF-Y is rapidly established upon BCL11A depletion, and precedes γ-globin derepression and LCR-globin loop formation. Our findings reveal that the critical fetal-to-adult hemoglobin switch is initiated by the competition between transcription factors within a discrete region in the γ-globin promoters.
2020-12-22 | GSE150529 | GEO
Project description:BCL11A, the major regulator of HbF(α2γ2) level, represses γ-globin expression through direct promoter binding in adult erythroid cells in a switch to adult adult-type HbA (α2β2) production. Yet, the mechanism remains unclear. To uncover how BCL11A initiates repression, we used CRISPR/Cas9 and dCas9 screens to dissect the γ-globin promoters and identified an apparent activator element near the BCL11A binding region. Using CUT&RUN and base editing approaches, we demonstrate that this element, the proximal CCAAT box, is the binding site of transcription activator NF-Y. BCL11A competes with NF-Y binding through steric hindrance to initiate γ-globin repression, and the distance between the two motifs is critical for direct competition. Occupancy of NF-Y is rapidly established upon BCL11A depletion, and precedes γ-globin derepression and LCR-globin loop formation. Our findings reveal that the critical fetal-to-adult hemoglobin switch is initiated by the competition between transcription factors within a discrete region in the γ-globin promoters.
2020-12-22 | GSE150491 | GEO