Project description:CHARGE syndrome is caused by heterozygous mutations in a chromatin remodeler CHD7 and characterized by a set of malformations historically postulated to arise from defects in the neural crest formation during embryogenesis. To better delineate neural crest defects in CHARGE syndrome, we generated induced pluripotent stem cells (iPSCs) from two patients with typical syndrome manifestations, and characterized neural crest cells differentiated in vitro from these iPSCs (iPSC-NCCs). We found that expression of genes associated with cell migration was altered in CHARGE iPSC-NCCs as compared to control iPSC-NCCs. Consistently, CHARGE iPSC-NCCs showed defective delamination, migration and motility in vitro, and their transplantation in ovo revealed overall defective migratory activity in the chick embryo. Altogether, our results support the historical inference that CHARGE syndrome patients have defects in neural crest migration and provide the first successful application of patient-derived iPSCs in modeling craniofacial disorders.
Project description:Mutations in CHD7, encoding ATP-dependent chromodomain-helicase-DNA-binding protein 7, in CHARGE syndrome leads to multiple congenital anomalies including growth retardation, craniofacial malformations and neurological dysfunction. Currently, mechanisms underlying the CNS phenotypes remain poorly understood. Here, we show that Chd7 is a direct transcriptional target of oligodendrogenesis-promoting factors Olig2 and Brg1 and required for proper timing of CNS myelination and remyelination. Genome-occupancy analyses coupled with transcriptome profiling reveal that Chd7 cooperates with Sox10 to target the enhancers of key myelinogenic genes, and identify novel Chd7 target. Examination of Chd7 and Sox10 genomewide occupancy in differentiating oligodendrocytes
Project description:Mutations in CHD7, encoding ATP-dependent chromodomain-helicase-DNA-binding protein 7, in CHARGE syndrome leads to multiple congenital anomalies including growth retardation, craniofacial malformations and neurological dysfunction. Currently, mechanisms underlying the CNS phenotypes remain poorly understood. Here, we show that Chd7 is a direct transcriptional target of oligodendrogenesis-promoting factors Olig2 and Brg1 and required for proper timing of CNS myelination and remyelination. Genome-occupancy analyses coupled with transcriptome profiling reveal that Chd7 cooperates with Sox10 to target the enhancers of key myelinogenic genes, and identify novel Chd7 target. 4 RNA-Seq samples from P8 spinal cords of Ctrl and Chd7 cKO mice (duplicatess, Ctrl and cKO)
Project description:Mutations in CHD7, encoding ATP-dependent chromodomain-helicase-DNA-binding protein 7, in CHARGE syndrome leads to multiple congenital anomalies including growth retardation, craniofacial malformations and neurological dysfunction. Currently, mechanisms underlying the CNS phenotypes remain poorly understood. Here, we show that Chd7 is a direct transcriptional target of oligodendrogenesis-promoting factors Olig2 and Brg1 and required for proper timing of CNS myelination and remyelination. Genome-occupancy analyses coupled with transcriptome profiling reveal that Chd7 cooperates with Sox10 to target the enhancers of key myelinogenic genes, and identify novel Chd7 target.
Project description:Mutations in CHD7, encoding ATP-dependent chromodomain-helicase-DNA-binding protein 7, in CHARGE syndrome leads to multiple congenital anomalies including growth retardation, craniofacial malformations and neurological dysfunction. Currently, mechanisms underlying the CNS phenotypes remain poorly understood. Here, we show that Chd7 is a direct transcriptional target of oligodendrogenesis-promoting factors Olig2 and Brg1 and required for proper timing of CNS myelination and remyelination. Genome-occupancy analyses coupled with transcriptome profiling reveal that Chd7 cooperates with Sox10 to target the enhancers of key myelinogenic genes, and identify novel Chd7 target.
Project description:Regulation of chromatin plays fundamental roles in the normal development of the brain. Haploinsufficiency of the chromatin remodeling enzyme CHD7 causes CHARGE syndrome, a genetic disorder that prominently affects the development of the cerebellum. However, how CHD7 controls chromatin states in the cerebellum remains incompletely understood. Using conditional knockout of CHD7 in granule cell precursors in the mouse cerebellum, we find that CHD7 robustly promotes the accessibility and activity of enhancers in granule cell precursors. Remarkably, in vivo profiling of genome architecture reveals that CHD7 operates locally to stimulate enhancer activation, thereby driving the expression of topologically-interacting genes. Genome and gene ontology studies show that CHD7-regulated enhancers are associated prominently with genes that control brain tissue morphogenesis. Accordingly, conditional knockout of CHD7 triggers a striking phenotype of cerebellar polymicrogyria, which we have also found in a case of CHARGE syndrome. Finally, we uncover a CHD7-dependent switch in the preferred orientation of granule cell precursor division in the developing cerebellum, providing a cellular basis for the cerebellar polymicrogyria phenotype upon loss of CHD7. Collectively, our findings define CHD7 function in the regulation of the epigenome in granule cell precursors and identify a surprising link of CHD7 to the control of cerebellar cortical morphogenesis, with potential implications for our understanding of CHARGE syndrome.
Project description:Epigenetic dysregulation has emerged as mechanism in the etiology of neurodevelopmental disorders. Two such disorders, CHARGE and Kabuki syndromes, result from loss of function mutations in chromodomain helicase DNA-binding protein 7 (CHD7LOF) and lysine (K) methyltransferase 2D (KMT2DLOF), respectively. We expected that epigenetically driven developmental pathways regulated by CHD7 and KMT2D would overlap and that DNA methylation (DNAm) alterations downstream of the mutations in these genes would identify common target genes, elucidating a mechanistic link between these conditions, as well as specific target genes for each. Genome-wide DNAm profiles in individuals with CHARGE and Kabuki syndromes with CHD7LOF or KMT2DLOF identified distinct sets of DNAm differences in each of the disorders, which were used to generate two unique, highly specific and sensitive DNAm signatures. These DNAm signatures were able to differentiate pathogenic mutations in these two genes from controls and from each other. Analysis of each gene-specific DNAm signature identified common gene targets which could account for some of the clinical overlap in these syndromes, as well as distinct gene targets. Our findings demonstrate how characterization of the epigenome can contribute to our understanding of disease pathophysiology for epigenetic disorders, paving the way for explorations of novel therapeutics.
Project description:We hypothesized that the positive charge of CRP K100 is important for transcription of Class II CRP-dependent genes. These data show mutations that affect K100 charge status result in genome-wide changes in transcription of both CRP-dependent and -independent genes.
