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The impact of pro-inflammatory cytokines on the β-cell regulatory landscape provides insights into the genetics of type 1 diabtes [UMI-4C]

ABSTRACT: Early stages of type 1 diabetes (T1D) are characterized by local autoimmune inflammation and progressive loss of insulin-producing pancreatic β cells. We show here that exposure to pro-inflammatory cytokines unmasks a striking plasticity of the β-cell regulatory landscape. We expand the repertoire of human islet regulatory elements by mapping stimulus-responsive enhancers linked to changes in the β-cell transcriptome, proteome and 3D chromatin structure. Our data indicates that the β cell response to cytokines is mediated by the induction of novel regulatory regions as well as the activation of primed regulatory elements pre-bound by islet-specific transcription factors. We found that T1D-associated loci are enriched of the newly mapped cis-regulatory regions and identify T1D-associated variants disrupting cytokine-responsive enhancer activity in human β cells. Our study illustrates how β cells respond to a pro-inflammatory environment and implicate a role for stimulus-response islet enhancers in T1D.

ORGANISM(S): Homo sapiens

PROVIDER: GSE136865 | GEO | 2019/09/20

REPOSITORIES: GEO

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The impact of pro-inflammatory cytokines on the β-cell regulatory landscape provides insights into the genetics of type 1 diabetes

Project description:Early stages of type 1 diabetes (T1D) are characterized by local autoimmune inflammation and progressive loss of insulin-producing pancreatic β cells. We show here that exposure to pro-inflammatory cytokines unmasks a marked plasticity of the β-cell regulatory landscape. We expand the repertoire of human islet regulatory elements by mapping stimulus-responsive enhancers linked to changes in the β-cell transcriptome, proteome and 3D chromatin structure. Our data indicates that the β cell response to cytokines is mediated by the induction of novel regulatory regions as well as the activation of primed regulatory elements pre-bound by islet-specific transcription factors. We found that T1D-associated loci are enriched of the newly mapped cis-regulatory regions and identify T1D-associated variants disrupting cytokine-responsive enhancer activity in human β cells. Our study illustrates how β cells respond to a pro-inflammatory environment and implicate a role for stimulus-response islet enhancers in T1D.

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The impact of pro-inflammatory cytokines on the β-cell regulatory landscape provides insights into the genetics of type 1 diabtes [H3K27ac ChIP-seq]

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The impact of pro-inflammatory cytokines on the β-cell regulatory landscape provides insights into the genetics of type 1 diabtes [ATAC-seq]

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