Similar Datasets
Project description:The CFTR gene lies within an invariant topologically associated domain (TAD) demarcated by CTCF and cohesin, but shows cell-type specific control mechanisms utilizing different cis-regulatory elements (CRE) within the TAD. Within the respiratory epithelium, more than one cell type expresses CFTR and the molecular mechanisms controlling its transcription are likely divergent between them. Here, we determine how two extragenic CREs that are prominent in epithelial cells in the lung, regulate expression of the gene. We showed earlier that these CREs, located at -44 and -35 kb upstream of the promoter, have strong cell-type-selective enhancer function. They are also responsive to inflammatory mediators and to oxidative stress, consistent with a key role in CF lung disease. Here, we use CRISPR/Cas9 technology to remove these CREs from the endogenous locus in human bronchial epithelial cells. Loss of either site extinguished CFTR expression and abolished long-range interactions between these sites and the gene promoter, suggesting non-redundant enhancers. The deletions also greatly reduced promoter interactions with the 5' TAD boundary. We show substantial recruitment of RNAPII to the -35 kb element and identify CEBPβ as a key activator of airway expression of CFTR, likely through occupancy at this CRE and the gene promoter.
| S-EPMC7144911 | biostudies-literature
Project description:The CFTR gene lies within an invariant topologically associated domain (TAD) demarcated by CTCF and cohesin, but shows cell-type specific control mechanisms utilizing different cis-regulatory elements (CRE) within the TAD. Within the respiratory epithelium, more than one cell type expresses CFTR and the molecular mechanism controlling its transcription are likely divergent between them. Here we determine how two extragenic CREs that are prominent in secretory epithelial cells in the lung, regulate expression of the gene. We showed earlier that these CREs, located at -44kb and -35 kb upstream of the promoter, have strong cell-type-selective enhancer function. They are also responsive to inflammatory mediators and to oxidative stress, consistent with a key role in CF lung disease. Here we use CRISPR/Cas9 technology to remove these CREs from the endogenous locus in human bronchial epithelial cells. Loss of either site extinguished CFTR expression and abolished long-range interactions between these sites and the gene promoter. The deletions also greatly reduced promoter interactions with the 5’ TAD boundary. We show substantial recruitment of RNAPII to the -35kb element and identify CEBPβ as a key activating transcription factor for airway expression of CFTR, likely through occupancy at both the CRE and the gene promoter.
2020-04-22 | GSE138166 | GEO
Project description:The CFTR gene lies within an invariant topologically associated domain (TAD) demarcated by CTCF and cohesin, but shows cell-type specific control mechanisms utilizing different cis-regulatory elements (CRE) within the TAD. Within the respiratory epithelium, more than one cell type expresses CFTR and the molecular mechanism controlling its transcription are likely divergent between them. Here we determine how two extragenic CREs that are prominent in secretory epithelial cells in the lung, regulate expression of the gene. We showed earlier that these CREs, located at -44kb and -35 kb upstream of the promoter, have strong cell-type-selective enhancer function. They are also responsive to inflammatory mediators and to oxidative stress, consistent with a key role in CF lung disease. Here we use CRISPR/Cas9 technology to remove these CREs from the endogenous locus in human bronchial epithelial cells. Loss of either site extinguished CFTR expression and abolished long-range interactions between these sites and the gene promoter. The deletions also greatly reduced promoter interactions with the 5’ TAD boundary. We show substantial recruitment of RNAPII to the -35kb element and identify CEBPβ as a key activating transcription factor for airway expression of CFTR, likely through occupancy at both the CRE and the gene promoter.
2020-04-22 | GSE132807 | GEO
Project description:The CFTR gene lies within an invariant topologically associated domain (TAD) demarcated by CTCF and cohesin, but shows cell-type specific control mechanisms utilizing different cis-regulatory elements (CRE) within the TAD. Within the respiratory epithelium, more than one cell type expresses CFTR and the molecular mechanism controlling its transcription are likely divergent between them. Here we determine how two extragenic CREs that are prominent in secretory epithelial cells in the lung, regulate expression of the gene. We showed earlier that these CREs, located at -44kb and -35 kb upstream of the promoter, have strong cell-type-selective enhancer function. They are also responsive to inflammatory mediators and to oxidative stress, consistent with a key role in CF lung disease. Here we use CRISPR/Cas9 technology to remove these CREs from the endogenous locus in human bronchial epithelial cells. Loss of either site extinguished CFTR expression and abolished long-range interactions between these sites and the gene promoter. The deletions also greatly reduced promoter interactions with the 5’ TAD boundary. We show substantial recruitment of RNAPII to the -35kb element and identify CEBPβ as a key activating transcription factor for airway expression of CFTR, likely through occupancy at both the CRE and the gene promoter.
2020-04-22 | GSE132806 | GEO
Project description:Looping of upstream cis-regulatory elements is required for CFTR expression in human airway epithelial cells
| PRJNA549085 | ENA
Project description:Looping of upstream cis-regulatory elements is required for CFTR expression in human airway epithelial cells [ChIP-seq]
| PRJNA549087 | ENA
Project description:Looping of upstream cis-regulatory elements is required for CFTR expression in human airway epithelial cells [4C-seq]
| PRJNA574955 | ENA
Project description:Looping of upstream cis-regulatory elements is required for CFTR expression in human airway epithelial cells [Omni-ATAC-seq]
| PRJNA549086 | ENA
Project description:Identification of regulatory elements and their target genes is complicated by the fact that regulatory elements can act over large genomic distances. Identification of long-range acting elements is particularly important in the case of disease genes as mutations in these elements can result in human disease. It is becoming increasingly clear that long-range control of gene expression is facilitated by chromatin looping interactions. These interactions can be detected by chromosome conformation capture (3C). Here, we employed 3C as a discovery tool for identification of long-range regulatory elements that control the cystic fibrosis transmembrane conductance regulator gene, CFTR. We identified four elements in a 460-kb region around the locus that loop specifically to the CFTR promoter exclusively in CFTR expressing cells. The elements are located 20 and 80 kb upstream; and 109 and 203 kb downstream of the CFTR promoter. These elements contain DNase I hypersensitive sites and histone modification patterns characteristic of enhancers. The elements also interact with each other and the latter two activate the CFTR promoter synergistically in reporter assays. Our results reveal novel long-range acting elements that control expression of CFTR and suggest that 3C-based approaches can be used for discovery of novel regulatory elements.
| S-EPMC2910055 | biostudies-literature
Project description:BackgroundCell-specific and developmental mechanisms contribute to expression of the cystic fibrosis transmembrane conductance regulator (CFTR) gene; however, its developmental regulation is poorly understood. Here we use human induced pluripotent stem cells differentiated into pseudostratified airway epithelial cells to study these mechanisms.ResultsChanges in gene expression and open chromatin profiles were investigated by RNA-seq and ATAC-seq, and revealed that alterations in CFTR expression are associated with differences in stage-specific open chromatin. Additionally, two novel open chromatin regions, at +19.6 kb and +22.6 kb 3' to the CFTR translational stop signal, were observed in definitive endoderm (DE) cells, prior to an increase in CFTR expression in anterior foregut endoderm (AFE) cells. Chromatin studies in DE and AFE cells revealed enrichment of active enhancer marks and occupancy of OTX2 at these sites in DE cells. Loss of OTX2 in DE cells alters histone modifications across the CFTR locus and results in a 2.5-fold to 5-fold increase in CFTR expression. However, deletion of the +22.6 kb site alone does not affect CFTR expression in DE or AFE cells.ConclusionsThese results suggest that a network of interacting cis-regulatory elements recruit OTX2 to the locus to impact CFTR expression during early endoderm differentiation.
| S-EPMC11227118 | biostudies-literature