Project description:The genomic repertoire of enhancers and promoters that control the transcriptional output of terminally differentiated cells includes cell type-specific and housekeeping elements. Whether the constitutive activity of these two groups of cis-regulatory elements relies on entirely distinct or instead shared regulators is unknown. By dissecting the cis-regulatory repertoire of macrophages, we found that the ELF subfamily of ETS proteins selectively bound within 60 bp from the transcription start sites of highly active housekeeping genes. ELFs also bound constitutively active, but not poised macrophage-specific enhancers and promoters. The role of ELFs in promoting constitutive transcription is suggested by multiple evidences: ELF sites enabled transcriptional activation by endogenous and minimal synthetic promoters; ELF recruitment was stabilized by the transcriptional machinery, and ELF proteins mediated recruitment of transcriptional and chromatin regulators to core promoters. These data indicate that a distinct subfamily of ETS proteins imparts high transcriptional activity to a broad range of housekeeping and tissue-specific cis-regulatory elements, which is consistent with the role of an ETS family ancestor in core promoter regulation in a lower eukaryote.
Project description:The genomic repertoire of enhancers and promoters that control the transcriptional output of terminally differentiated cells includes cell type-specific and housekeeping elements. Whether the constitutive activity of these two groups of cis-regulatory elements relies on entirely distinct or instead shared regulators is unknown. By dissecting the cis-regulatory repertoire of macrophages, we found that the ELF subfamily of ETS proteins selectively bound within 60 bp from the transcription start sites of highly active housekeeping genes. ELFs also bound constitutively active, but not poised macrophage-specific enhancers and promoters. The role of ELFs in promoting constitutive transcription is suggested by multiple evidences: ELF sites enabled transcriptional activation by endogenous and minimal synthetic promoters; ELF recruitment was stabilized by the transcriptional machinery, and ELF proteins mediated recruitment of transcriptional and chromatin regulators to core promoters. These data indicate that a distinct subfamily of ETS proteins imparts high transcriptional activity to a broad range of housekeeping and tissue-specific cis-regulatory elements, which is consistent with the role of an ETS family ancestor in core promoter regulation in a lower eukaryote.
Project description:The genomic repertoire of enhancers and promoters that control the transcriptional output of terminally differentiated cells includes cell type-specific and housekeeping elements. Whether the constitutive activity of these two groups of cis-regulatory elements relies on entirely distinct or instead shared regulators is unknown. By dissecting the cis-regulatory repertoire of macrophages, we found that the ELF subfamily of ETS proteins selectively bound within 60 bp from the transcription start sites of highly active housekeeping genes. ELFs also bound constitutively active, but not poised macrophage-specific enhancers and promoters. The role of ELFs in promoting constitutive transcription is suggested by multiple evidences: ELF sites enabled transcriptional activation by endogenous and minimal synthetic promoters; ELF recruitment was stabilized by the transcriptional machinery, and ELF proteins mediated recruitment of transcriptional and chromatin regulators to core promoters. These data indicate that a distinct subfamily of ETS proteins imparts high transcriptional activity to a broad range of housekeeping and tissue-specific cis-regulatory elements, which is consistent with the role of an ETS family ancestor in core promoter regulation in a lower eukaryote.
Project description:The development and function of stem and progenitor cells that produce blood cells are vital in physiology. GATA2 mutations cause immunodeficiency, myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). GATA-2 physiological activities necessitate that it be strictly regulated and cell type-specific enhancers fulfill this role. The +9.5 intronic enhancer harbors multiple conserved cis-elements, and germline mutations of these cis-elements are pathogenic in humans. Since mechanisms underlying how GATA2 enhancer disease mutations impact hematopoiesis and pathology are unclear, we generated mouse models of the enhancer mutations. While a multi-motif mutant was embryonic lethal, a single-nucleotide Ets motif mutant was viable and steady-state hematopoiesis was normal. However, the Ets motif mutation abrogated stem/progenitor cell regeneration following stress. These results reveal a new mechanism in human genetics in which a disease mutation inactivates enhancer regenerative activity, while sparing developmental activity. Mutational sensitization to stress that instigates hematopoietic failure constitutes a paradigm for GATA-2-dependent pathogenesis.
Project description:Developmental control of gene expression critically depends on distal cis-regulatory elements including enhancers which interact with promoters to activate gene expression. Multiple genome-wide studies have mapped chromatin and genomic features of such elements. However, the enhancer definition is operational, and no global experiments have been conducted to date that identify their cell type and cell stage-specific transcription stimulatory activity in a chromatin context. Here, we describe a high-throughput method that identifies thousands of cis-elements capable of stimulating transcriptional activity from a minimal promoter using the blood progenitor differentiation from embryonic stem cells as model. We show that hematopoietic specification and blood cell-specific gene expression are controlled by the concerted action of thousands of differentiation stage-specific sets of cis-elements which respond to cytokine signals terminating at signalling responsive transcription factors. Our work presents a major advance in our understanding of developmental gene expression control in the hematopoietic system and beyond.
Project description:Developmental control of gene expression critically depends on distal cis-regulatory elements including enhancers which interact with promoters to activate gene expression. Multiple genome-wide studies have mapped chromatin and genomic features of such elements. However, the enhancer definition is operational, and no global experiments have been conducted to date that identify their cell type and cell stage-specific transcription stimulatory activity in a chromatin context. Here, we describe a high-throughput method that identifies thousands of cis-elements capable of stimulating transcriptional activity from a minimal promoter using the blood progenitor differentiation from embryonic stem cells as model. We show that hematopoietic specification and blood cell-specific gene expression are controlled by the concerted action of thousands of differentiation stage-specific sets of cis-elements which respond to cytokine signals terminating at signalling responsive transcription factors. Our work presents a major advance in our understanding of developmental gene expression control in the hematopoietic system and beyond.
Project description:Developmental control of gene expression critically depends on distal cis-regulatory elements including enhancers which interact with promoters to activate gene expression. Multiple genome-wide studies have mapped chromatin and genomic features of such elements. However, the enhancer definition is operational, and no global experiments have been conducted to date that identify their cell type and cell stage-specific transcription stimulatory activity in a chromatin context. Here, we describe a high-throughput method that identifies thousands of cis-elements capable of stimulating transcriptional activity from a minimal promoter using the blood progenitor differentiation from embryonic stem cells as model. We show that hematopoietic specification and blood cell-specific gene expression are controlled by the concerted action of thousands of differentiation stage-specific sets of cis-elements which respond to cytokine signals terminating at signalling responsive transcription factors. Our work presents a major advance in our understanding of developmental gene expression control in the hematopoietic system and beyond.