Project description:Neuronal brain region-specific DNA methylation and chromatin accessibility are associated with neuropsychiatric trait heritability [ATAC-Seq]
Project description:Neuronal brain region-specific DNA methylation and chromatin accessibility are associated with neuropsychiatric trait heritability [Bisulfite-Seq]
Project description:Brain region- and cell-specific transcriptome and epigenome molecular features are associated with heritability for neuropsychiatric traits. Here, we provide an atlas of chromatin accessibility and gene expression in neuronal and non-neuronal cells across 25 distinct regions across cortical and subcortical areas of the human brain from 6 neurotypical controls. We identified extensive gene expression and chromatin accessibility differences across brain regions. We further identified variation in alternative promoter-isoform usage and enhancer-promoter interactions across brain regions and found genes with distinct promoter-isoform usage are strongly enriched for neuropsychiatric risk variants. We identified brain region-specific chromatin co-accessibility and gene-coexpression modules that are robustly associated with genetic risk variants for neuropsychiatric disorders. Using an integrative approach, we identify a novel set of genes that is enriched for neuropsychiatric disorders risk variants but is independent of cell-type specific gene expression and annotated pathways. Our results provide a valuable multi-brain region molecular regulation resource and suggest a unique contribution of epigenetic modifications from the subcortical areas to neuropsychiatric disorders.
Project description:Brain region- and cell-specific transcriptome and epigenome molecular features are associated with heritability for neuropsychiatric traits. Here, we provide an atlas of chromatin accessibility and gene expression in neuronal and non-neuronal cells across 25 distinct regions across cortical and subcortical areas of the human brain from 6 neurotypical controls. We identified extensive gene expression and chromatin accessibility differences across brain regions. We further identified variation in alternative promoter-isoform usage and enhancer-promoter interactions across brain regions and found genes with distinct promoter-isoform usage are strongly enriched for neuropsychiatric risk variants. We identified brain region-specific chromatin co-accessibility and gene-coexpression modules that are robustly associated with genetic risk variants for neuropsychiatric disorders. Using an integrative approach, we identify a novel set of genes that is enriched for neuropsychiatric disorders risk variants but is independent of cell-type specific gene expression and annotated pathways. Our results provide a valuable multi-brain region molecular regulation resource and suggest a unique contribution of epigenetic modifications from the subcortical areas to neuropsychiatric disorders.
Project description:The majority of common genetic risk variants associated with neuropsychiatric disease are non-coding and are thought to exert their effects by disrupting the function of cis regulatory elements (CREs), including promoters and enhancers. Within each cell, chromatin is arranged in specific patterns to expose the repertoire of CREs required for optimal spatiotemporal regulation of gene expression. To further our understanding of the complex mechanisms that modulate transcription in the brain, we utilized frozen postmortem samples to generate the largest human brain and cell type-specific open chromatin dataset to date. Using the Assay for Transposase Accessible Chromatin followed by sequencing (ATAC-seq), we created maps of chromatin accessibility in 2 cell types (neurons and non-neurons) across 14 distinct brain regions of 5 individuals. Chromatin structure varies markedly by cell type, with neuronal chromatin displaying higher regional variability than that of non-neurons. Among our findings is an open chromatin region (OCR) specific to neurons of the striatum. When placed in the mouse, a human sequence derived from this OCR recapitulates the cell-type and regional expression pattern predicted by our ATAC-seq experiments. Furthermore, differentially accessible chromatin overlaps with the genetic architecture of neuropsychiatric traits and identifies differences in molecular pathways and biological functions. By leveraging transcription factor binding analysis, we identify protein coding and long noncoding RNAs (lncRNAs) with cell-type and brain region specificity. Our data provides a valuable resource to the research community and we provide this human brain chromatin accessibility atlas as an online database “Brain Open Chromatin Atlas (BOCA)” to facilitate interpretation.
Project description:Background: Deletions in the 15q13.3 region are associated with several neuropsychiatric disorders, including autism and schizophrenia. Association studies in humans and functional studies in mice have suggested that several genes within the 15q13.3 microdeletion may play a role in neuronal dysfunction, but the intermediate molecular mechanisms remain unknown. Methods: Induced pluripotent stem cells from 3 patients with the 15q13.3 microdeletion and 3 sex-matched controls were generated and converted into induced neurons. We analyzed the genome-wide effects of the 15q13.3 microdeletion on gene expression, DNA methylation, chromatin accessibility, and sensitivity to cisplatin-induced DNA damage. We also evaluated gene expression changes in induced neurons containing CRISPR knockouts of single 15q13.3 microdeletion genes. Results: In both cell types, gene copy number change within the 15q13.3 microdeletion was accompanied by significantly decreased gene expression and no compensatory changes in DNA methylation or chromatin accessibility, supporting the model that haploinsufficiency of genes within the deleted region drives the disorder. Further, we observed global effects of the microdeletion on the transcriptome and epigenome, with disruptions in several neuropsychiatric disorder-associated pathways, such as Wnt signaling, ribosome biogenesis, DNA binding, and cell adhesion. Conclusions: Our multi-omics analyses of the 15q13.3 microdeletion revealed downstream effects in pathways previously associated with neuropsychiatric disorders. This molecular systems analysis can also be applied to other brain relevant chromosomal aberrations to further our etiological understanding of neuropsychiatric disorders.
Project description:Human brain development starts during embryogenesis and extends postnatally to adulthood. During this time, the cellular complexity of the brain is established via dynamic changes in gene expression, mediated, in part, by the spatiotemporal activity of cis-regulatory elements. To better understand these processes, we performed simultaneous profiling of gene expression and chromatin accessibility in 45,549 individual nuclei, isolated from the human cortex across 6 broad developmental time-points from fetus to adult. We identified cell-type specific domains in which chromatin accessibility is highly correlated with gene expression. Differentiation pseudotime trajectories of gene expression in neuronal subpopulations indicate that chromatin accessibility at cis-regulatory elements precedes transcription and that dynamic changes in chromatin structure play a critical role in neuronal lineage commitment. In addition, using lineage-specific genes and peaks, we mapped cell-type specific genetic loci implicated in neuropsychiatric traits, including schizophrenia, major depressive disorder and bipolar disorder. Together, our results describe the complex regulation of cell composition at critical stages in lineage determination, serve as a developmental blueprint of the human brain and shed light on the impact of spatiotemporal alterations in gene expression on neuropsychiatric disease.
Project description:Human brain development starts during embryogenesis and extends postnatally to adulthood. During this time, the cellular complexity of the brain is established via dynamic changes in gene expression, mediated, in part, by the spatiotemporal activity of cis-regulatory elements. To better understand these processes, we performed simultaneous profiling of gene expression and chromatin accessibility in 45,549 individual nuclei, isolated from the human cortex across 6 broad developmental time-points from fetus to adult. We identified cell-type specific domains in which chromatin accessibility is highly correlated with gene expression. Differentiation pseudotime trajectories of gene expression in neuronal subpopulations indicate that chromatin accessibility at cis-regulatory elements precedes transcription and that dynamic changes in chromatin structure play a critical role in neuronal lineage commitment. In addition, using lineage-specific genes and peaks, we mapped cell-type specific genetic loci implicated in neuropsychiatric traits, including schizophrenia, major depressive disorder and bipolar disorder. Together, our results describe the complex regulation of cell composition at critical stages in lineage determination, serve as a developmental blueprint of the human brain and shed light on the impact of spatiotemporal alterations in gene expression on neuropsychiatric disease.
Project description:We analyzed differential methylation (via WGBS) between four distinct human brain regions (NAcc-nucleus accumbens, BA9-dorsolateral prefrontal cortex, BA24-anterior cingulate cortex, and HC-hippocampus) in both sorted nuclei and intact tissues. We isolated neuronal and non-neuronal (glial) nuclei from the same six individuals for each tissue via FACS using the neuronal marker, NeuN. Additionally, we performed WGBS from non-sorted tissues from these same brain regions in a total of 12 individuals (BA9 n = 9; BA24 n = 5; HC n = 6; NAcc n = 7). To complement our DNA methylation analyses, we measured gene expression (RNA-seq) and chromatin accessibility (ATAC-seq) in neuronal and non-neuronal nuclei from the nucleus accumbens and dorsolateral prefrontal cortex from six more individuals. We then performed an integrative analysis to understand how the epigenome contributes to brain region-specific function.