Project description:VHL loss is the most common genetic alteration event in ccRCC, but its effect on epigenetic landscape has not been elucidated previously. By performing histone modifications (H3K27ac, H3K4me1, H3K4me3) from ccRCC cell lines, we describe the genome-wide cis-regulatory landscapes of VHL-deficient ccRCC tumors. We show that ccRCCs exhibit a pervasive gain of enhancers around hypoxic and metabolic transcriptional targets.
Project description:VHL loss is the most common genetic alteration event in ccRCC, but its effect on epigenetic landscape has not been elucidated previously. By performing histone modifications (H3K27ac, H3K4me1, H3K4me3) from ccRCC cell lines, we describe the genome-wide cis-regulatory landscapes of VHL-deficient ccRCC tumors. We show that ccRCCs exhibit a pervasive gain of enhancers around hypoxic and metabolic transcriptional targets.
Project description:MDMA (ecstasy) is an illicit drug that stimulates monoamine neurotransmitter release and inhibits reuptake. MDMAâs acute cardiotoxicity includes tachycardia and arrhythmia which are associated with cardiomyopathy (CM). MDMA acute cardiotoxicity has been explored, but neither long-term MDMA cardiac pathological changes nor epigenetic changes have been evaluated. Microarray analyses were employed to identify cardiac gene expression changes and epigenetic DNA methylation changes. To identify permanent MDMA-induced pathogenetic changes, mice received daily 10d or 35d MDMA , or daily 10d MDMA followed by 25d saline washout (10+25d). MDMA treatment (10d) caused differentially gene expression (p<0.05, fold change >1.5), with 752 genes 558 genes following 35d MDMA, and 113 genes following 10d treatment +25d washout. Changes in MAPK and circadian rhythm gene expression were identified following 10d administration. After 35d, circadian rhythm genes (Per3, CLOCK, ARNTL, and NPAS2) remained differentially expressed. MDMA caused DNA hypermethylation and hypomethylation that was independent of gene expression; hypermethylation of genes was 71% at 10d, 68% at 35d, and 91% at 10+25d. Differential gene expression that corresponded directly with DNA methylation changes occurred in 22% of genes at 10d, 17% at 35d, and 48% at 10d+25d washout. MDMA treatment resulted in epigenetic changes in cardiac DNA methylation. Hypermethylation was the predominant effect. MDMA induced gene expression of key elements of circadian rhythm regulatory genes and suggest a fundamental mechanism for MDMA dysfunction in the heart. This study addresses how MDMA (ecstasy) affects cardiac (left ventricle) gene expression and epigenetic nuclear DNA methylation. Each sample was fluorescently labeled and hybridized to Roche Nimblegen 2.1M Deluxe Promoter Arrays.
Project description:MDMA (ecstasy) is an illicit drug that stimulates monoamine neurotransmitter release and inhibits reuptake. MDMAâs acute cardiotoxicity includes tachycardia and arrhythmia which are associated with cardiomyopathy (CM). MDMA acute cardiotoxicity has been explored, but neither long-term MDMA cardiac pathological changes nor epigenetic changes have been evaluated. Microarray analyses were employed to identify cardiac gene expression changes and epigenetic DNA methylation changes. To identify permanent MDMA-induced pathogenetic changes, mice received daily 10d or 35d MDMA , or daily 10d MDMA followed by 25d saline washout (10+25d). MDMA treatment (10d) caused differentially gene expression (p<0.05, fold change >1.5), with 752 genes 558 genes following 35d MDMA, and 113 genes following 10d treatment +25d washout. Changes in MAPK and circadian rhythm gene expression were identified following 10d administration. After 35d, circadian rhythm genes (Per3, CLOCK, ARNTL, and NPAS2) remained differentially expressed. MDMA caused DNA hypermethylation and hypomethylation that was independent of gene expression; hypermethylation of genes was 71% at 10d, 68% at 35d, and 91% at 10+25d. Differential gene expression that corresponded directly with DNA methylation changes occurred in 22% of genes at 10d, 17% at 35d, and 48% at 10d+25d washout. MDMA treatment resulted in epigenetic changes in cardiac DNA methylation. Hypermethylation was the predominant effect. MDMA induced gene expression of key elements of circadian rhythm regulatory genes and suggest a fundamental mechanism for MDMA dysfunction in the heart. This study addresses how MDMA (ecstasy) affects cardiac (left ventricle) gene expression and epigenetic nuclear DNA methylation. Each sample was fluorescently labeled and hybridized to Roche Nimblegen 12X135kb MM9 Gene Expression Arrays.
Project description:The basic body plan and major physiological axes have been highly conserved during mammalian evolution, yet only a small fraction of the human genome sequence appears to be subject to evolutionary constraint. To quantify cis- versus trans-acting contributions to mammalian regulatory evolution, we performed genomic DNase I footprinting of the mouse genome across 25 cell and tissue types, collectively defining ~8.6 million transcription factor (TF) occupancy sites at nucleotide resolution. Here we show that mouse TF footprints conjointly encode a regulatory lexicon that is ~95% similar with that derived from human TF footprints. However, only ~20% of mouse TF footprints have human orthologues. Despite substantial turnover of the cis-regulatory landscape, nearly half of all pairwise regulatory interactions connecting mouse TF genes have been maintained in orthologous human cell types through evolutionary innovation of TF recognition sequences. Furthermore, the higher-level organization of mouse TF-to-TF connections into cellular network architectures is nearly identical with human. Our results indicate that evolutionary selection on mammalian gene regulation is targeted chiefly at the level of trans-regulatory circuitry, enabling and potentiating cis-regulatory plasticity. We performed genomic DNase I footprinting of the mouse genome across 25 cell and tissue types, collectively defining ~8.6 million transcription factor (TF) occupancy sites at nucleotide resolution.
Project description:The retina is composed of ~50 cell-types with specific functions for the process of vision. Identification of the cis-regulatory elements active in retinal cell-types is key to elucidate the networks controlling this diversity. Here, we combined transcriptome and epigenome profiling to map the regulatory landscape of four cell-types isolated from mouse retinas including rod and cone photoreceptors as well as rare inter-neuron populations such as horizontal and starburst amacrine cells. Integration of this information reveals sequence determinants and candidate transcription factors for controlling cellular specialization. Additionally, we refined parallel reporter assays to enable studying the transcriptional activity of large collection of sequences in individual cell-types isolated from a tissue. We provide proof of concept for this approach and its scalability by characterizing the transcriptional capacity of several hundred putative regulatory sequences within individual retinal cell-types. This generates a catalogue of cis-regulatory regions active in retinal cell types and we further demonstrate their utility as potential resource for cellular tagging and manipulation.