NF-kB and Circadian Enhancers Link β-cell Function with Anti-IL1B Therapy [RNA-seq]
Ontology highlight
ABSTRACT: Crosstalk between lineage-determining and signal-dependent transcription factors controls chromatin plasticity within heterogeneous tissues, yet how alterations in these interactions within single cells contribute to disease remains unknown. Here, by profiling chromatin activity in single nuclei of human pancreatic islets, we identified 19 clusters of cells, including β-cell subpopulations defined by differences in accessibility at non-coding cis-regulatory elements (CREs) for the lineage-determining factor pancreatic duodenal homeobox factor 1 (PDX1). Single cells with a high density of PDX1 CREs were enriched in accessible enhancer landscapes driving gene networks controlling nutrient sensing, insulin exocytosis, and circadian rhythms. In contrast, cells with reduced opening at PDX1 CREs had increased accessibility at regulatory elements for pro-inflammatory genes controlled by NF-kB and IL-1β. Genetic deficiency of Pdx1 in mice led to increased chromatin occupancy by the classical NF-κB subunit p65 and glucose intolerance that was more pronounced at the time of day when mice were awake and feeding. Within murine and human islets, PDX1 formed long-range repressive contacts with canonical regions of p65-mediated transcription. Pharmacological inhibition of signaling through the IL-1β receptor, an abundant β-cell target of p65, enhanced glucose-dependent insulin secretion in Pdx1-deficient β cells. Together, our single-cell epigenomic analyses provide a rationale to antagonize NF-kB signaling as an insulinotropic therapy for β-cell failure and diabetes.
Project description:Crosstalk between lineage-determining and signal-dependent transcription factors controls chromatin plasticity within heterogeneous tissues, yet how alterations in these interactions within single cells contribute to disease remains unknown. Here, by profiling chromatin activity in single nuclei of human pancreatic islets, we identified 19 clusters of cells, including β-cell subpopulations defined by differences in accessibility at non-coding cis-regulatory elements (CREs) for the lineage-determining factor pancreatic duodenal homeobox factor 1 (PDX1). Single cells with a high density of PDX1 CREs were enriched in accessible enhancer landscapes driving gene networks controlling nutrient sensing, insulin exocytosis, and circadian rhythms. In contrast, cells with reduced opening at PDX1 CREs had increased accessibility at regulatory elements for pro-inflammatory genes controlled by NF-kB and IL-1β. Genetic deficiency of Pdx1 in mice led to increased chromatin occupancy by the classical NF-κB subunit p65 and glucose intolerance that was more pronounced at the time of day when mice were awake and feeding. Within murine and human islets, PDX1 formed long-range repressive contacts with canonical regions of p65-mediated transcription. Pharmacological inhibition of signaling through the IL-1β receptor, an abundant β-cell target of p65, enhanced glucose-dependent insulin secretion in Pdx1-deficient β cells. Together, our single-cell epigenomic analyses provide a rationale to antagonize NF-kB signaling as an insulinotropic therapy for β-cell failure and diabetes.
Project description:Crosstalk between lineage-determining and signal-dependent transcription factors controls chromatin plasticity within heterogeneous tissues, yet how alterations in these interactions within single cells contribute to disease remains unknown. Here, by profiling chromatin activity in single nuclei of human pancreatic islets, we identified 19 clusters of cells, including β-cell subpopulations defined by differences in accessibility at non-coding cis-regulatory elements (CREs) for the lineage-determining factor pancreatic duodenal homeobox factor 1 (PDX1). Single cells with a high density of PDX1 CREs were enriched in accessible enhancer landscapes driving gene networks controlling nutrient sensing, insulin exocytosis, and circadian rhythms. In contrast, cells with reduced opening at PDX1 CREs had increased accessibility at regulatory elements for pro-inflammatory genes controlled by NF-kB and IL-1β. Genetic deficiency of Pdx1 in mice led to increased chromatin occupancy by the classical NF-κB subunit p65 and glucose intolerance that was more pronounced at the time of day when mice were awake and feeding. Within murine and human islets, PDX1 formed long-range repressive contacts with canonical regions of p65-mediated transcription. Pharmacological inhibition of signaling through the IL-1β receptor, an abundant β-cell target of p65, enhanced glucose-dependent insulin secretion in Pdx1-deficient β cells. Together, our single-cell epigenomic analyses provide a rationale to antagonize NF-kB signaling as an insulinotropic therapy for β-cell failure and diabetes.
Project description:Crosstalk between lineage-determining and signal-dependent transcription factors controls chromatin plasticity within heterogeneous tissues, yet how alterations in these interactions within single cells contribute to disease remains unknown. Here, by profiling chromatin activity in single nuclei of human pancreatic islets, we identified 19 clusters of cells, including β-cell subpopulations defined by differences in accessibility at non-coding cis-regulatory elements (CREs) for the lineage-determining factor pancreatic duodenal homeobox factor 1 (PDX1). Single cells with a high density of PDX1 CREs were enriched in accessible enhancer landscapes driving gene networks controlling nutrient sensing, insulin exocytosis, and circadian rhythms. In contrast, cells with reduced opening at PDX1 CREs had increased accessibility at regulatory elements for pro-inflammatory genes controlled by NF-kB and IL-1β. Genetic deficiency of Pdx1 in mice led to increased chromatin occupancy by the classical NF-κB subunit p65 and glucose intolerance that was more pronounced at the time of day when mice were awake and feeding. Within murine and human islets, PDX1 formed long-range repressive contacts with canonical regions of p65-mediated transcription. Pharmacological inhibition of signaling through the IL-1β receptor, an abundant β-cell target of p65, enhanced glucose-dependent insulin secretion in Pdx1-deficient β cells. Together, our single-cell epigenomic analyses provide a rationale to antagonize NF-kB signaling as an insulinotropic therapy for β-cell failure and diabetes.
Project description:Crosstalk between lineage-determining and signal-dependent transcription factors controls chromatin plasticity within heterogeneous tissues, yet how alterations in these interactions within single cells contribute to disease remains unknown. Here, by profiling chromatin activity in single nuclei of human pancreatic islets, we identified 19 clusters of cells, including β-cell subpopulations defined by differences in accessibility at non-coding cis-regulatory elements (CREs) for the lineage-determining factor pancreatic duodenal homeobox factor 1 (PDX1). Single cells with a high density of PDX1 CREs were enriched in accessible enhancer landscapes driving gene networks controlling nutrient sensing, insulin exocytosis, and circadian rhythms. In contrast, cells with reduced opening at PDX1 CREs had increased accessibility at regulatory elements for pro-inflammatory genes controlled by NF-kB and IL-1β. Genetic deficiency of Pdx1 in mice led to increased chromatin occupancy by the classical NF-κB subunit p65 and glucose intolerance that was more pronounced at the time of day when mice were awake and feeding. Within murine and human islets, PDX1 formed long-range repressive contacts with canonical regions of p65-mediated transcription. Pharmacological inhibition of signaling through the IL-1β receptor, an abundant β-cell target of p65, enhanced glucose-dependent insulin secretion in Pdx1-deficient β cells. Together, our single-cell epigenomic analyses provide a rationale to antagonize NF-kB signaling as an insulinotropic therapy for β-cell failure and diabetes.
Project description:Crosstalk between lineage-determining and signal-dependent transcription factors controls chromatin plasticity within heterogeneous tissues, yet how alterations in these interactions within single cells contribute to disease remains unknown. Here, by profiling chromatin activity in single nuclei of human pancreatic islets, we identified 19 clusters of cells, including β-cell subpopulations defined by differences in accessibility at non-coding cis-regulatory elements (CREs) for the lineage-determining factor pancreatic duodenal homeobox factor 1 (PDX1). Single cells with a high density of PDX1 CREs were enriched in accessible enhancer landscapes driving gene networks controlling nutrient sensing, insulin exocytosis, and circadian rhythms. In contrast, cells with reduced opening at PDX1 CREs had increased accessibility at regulatory elements for pro-inflammatory genes controlled by NF-kB and IL-1β. Genetic deficiency of Pdx1 in mice led to increased chromatin occupancy by the classical NF-κB subunit p65 and glucose intolerance that was more pronounced at the time of day when mice were awake and feeding. Within murine and human islets, PDX1 formed long-range repressive contacts with canonical regions of p65-mediated transcription. Pharmacological inhibition of signaling through the IL-1β receptor, an abundant β-cell target of p65, enhanced glucose-dependent insulin secretion in Pdx1-deficient β cells. Together, our single-cell epigenomic analyses provide a rationale to antagonize NF-kB signaling as an insulinotropic therapy for β-cell failure and diabetes.
Project description:Constitutive Kras and NF-kB activation is identified as signature alterations in human pancreatic ductal adenocarcinoma (PDAC). Here, we report that pancreas-targeted IKK2/beta inactivation inhibited NF-kB activation and completely suppressed PDAC development. Our findings demonstrated that NF-kB is required for development of pancreatic ductal adenocarcinoma that was initiated by Kras activation. Pancreatic tissue from 4 groups of mice were used in this project: (1) the pancreas normal appearance of Pdx1-cre;KrasLSL-G12D;IKK2/beta mice, (2) the normal pancreas of Pdx1-cre;KrasLSL-G12D mice, (3) the pancreatic lesion of pancreatic intraepithelial neoplasia (PanIN) of Pdx1-cre;KrasLSL-G12D mice, and (4) the pancreatic lesion of PDAC of Pdx1-cre;KrasLSL-G12D mice. Each group included three mice. RNA samples from mouse pancreas were hybridized on GeneChip Mouse Gene 1.0 ST arrays (Affymetrix). Group (1) and group (2) were compared, and group (2), group (3) and group (4) were compared.
Project description:Individual organisms age at different rates, however, it remains unclear how aging alters the properties of individual cells. Here we show that zebrafish pancreatic beta-cells exhibit heterogeneity in both gene expression and proliferation with age. Individual beta-cells show marked variability in transcripts involved in endoplasmic reticulum stress, inhibition of growth factor signaling and inflammation, including NF-kB signaling. Using a reporter line, we show that NF-kB signaling is indeed activated heterogeneously with age. Notably, beta-cells with higher NF-kB activity proliferate less compared to neighbors with lower activity. Furthermore, NF-kB-signalinghigh beta-cells from younger islets upregulate socs2, a gene naturally expressed in beta-cells from older islets. In turn, socs2 can inhibit proliferation cell-autonomously. NF-kB activation correlates with the recruitment of tnfα-expressing immune cells, pointing towards a role for the islet microenvironment in this activity. We propose that aging is heterogeneous across individual beta-cells and identify NF-kB signaling as a marker of heterogeneity.
Project description:Cytokines have been shown to play a key role in the destruction of beta cells. In the rat insulinoma cell line (INS-1ab) overexpressing pancreatic duodenum homeobox 1 (Pdx1) increases sensitivity to Interleukin 1b (IL-1b). To elucidate mechanisms of action underlying Pdx1 driven potentiation of beta-cell sensitivity to IL-1β, we performed a microarray analysis of INS-1ab cells with and without Pdx1 overexpression exposed to IL-1β between 2h and 24h.
Project description:Cytokines have been shown to play a key role in the destruction of beta cells. In the rat insulinoma cell line (INS-1ab) overexpressing pancreatic duodenum homeobox 1 (Pdx1) increases sensitivity to Interleukin 1b (IL-1b). To elucidate mechanisms of action underlying Pdx1 driven potentiation of beta-cell sensitivity to IL-1β, we performed a microarray analysis of INS-1ab cells with and without Pdx1 overexpression exposed to IL-1β between 2h and 24h. INS-1ab cells were cultured with or without 500 ng/ml doxycycline (+/- DOX). After 24 h, 40 ng/ml IL-1b was either added or not (+/- IL-1b). Cells were harvested either 2h, 4h, 6h, 12h or 24h after addition of IL-1b. Four biological replicates for each of the eight groups.