Inhibition of BET proteins rescues neural defects in Rett syndrome [scRNA-seq]
Ontology highlight
ABSTRACT: Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder caused by mutations in the methyl-CpG binding protein 2 (MeCP2). Cellular heterogeneity in the brain confounds the understanding of RTT etiology. To date, how MeCP2 mutation affects defined cell types in human brain remains unclear, and effective therapeutics for RTT is lacking. Here we show that cell-type-specific transcriptome impairment and JQ1-mediated rescue in RTT cells from dorsal and ventral human forebrain organoids. We find that MeCP2 mutation severely impairs human cortical interneurons (INs). Dysregulation of MeCP2-BRD4 regulatory axis and three-dimensional genome architecture are critically involved in the abnormal transcription in RTT INs, and JQ1 strongly rescues RTT INs by resetting the aberrant chromatin binding of BRD4. Finally, JQ1 alleviates RTT-like phenotypes in mice. These data demonstrate that BRD4 dysregulation is a critical driver for RTT etiology and targeting BRD4 is an effective therapeutic opportunity for RTT.
Project description:Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder caused by mutations in the methyl-CpG binding protein 2 (MeCP2). Cellular heterogeneity in the brain confounds the understanding of RTT etiology. To date, how MeCP2 mutation affects defined cell types in human brain remains unclear, and effective therapeutics for RTT is lacking. Here we show that cell-type-specific transcriptome impairment and JQ1-mediated rescue in RTT cells from dorsal and ventral human forebrain organoids. We find that MeCP2 mutation severely impairs human cortical interneurons (INs). Dysregulation of MeCP2-BRD4 ChIP regulatory axis and three-dimensional genome architecture are critically involved in the abnormal transcription in RTT INs, and JQ1 strongly rescues RTT INs by resetting the aberrant chromatin binding of BRD4 ChIP. Finally, JQ1 alleviates RTT-like phenotypes in mice. These data demonstrate that BRD4 ChIP dysregulation is a critical driver for RTT etiology and targeting BRD4 ChIP is an effective therapeutic opportunity for RTT.
Project description:Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder caused by mutations in the methyl-CpG binding protein 2 (MeCP2). Cellular heterogeneity in the brain confounds the understanding of RTT etiology. To date, how MeCP2 mutation affects defined cell types in human brain remains unclear, and effective therapeutics for RTT is lacking. Here we show that cell-type-specific transcriptome impairment and JQ1-mediated rescue in RTT cells from dorsal and ventral human forebrain organoids. We find that MeCP2 mutation severely impairs human cortical interneurons (INs). Dysregulation of MeCP2-BRD4 ChIP regulatory axis and three-dimensional genome architecture are critically involved in the abnormal transcription in RTT INs, and JQ1 strongly rescues RTT INs by resetting the aberrant chromatin binding of BRD4 ChIP. Finally, JQ1 alleviates RTT-like phenotypes in mice. These data demonstrate that BRD4 ChIP dysregulation is a critical driver for RTT etiology and targeting BRD4 ChIP is an effective therapeutic opportunity for RTT.
Project description:Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder caused by mutations in the methyl-CpG binding protein 2 (MeCP2). Cellular heterogeneity in the brain confounds the understanding of RTT etiology. To date, how MeCP2 mutation affects defined cell types in human brain remains unclear, and effective therapeutics for RTT is lacking. Here we show that cell-type-specific transcriptome impairment and JQ1-mediated rescue in RTT cells from dorsal and ventral human forebrain organoids. We find that MeCP2 mutation severely impairs human cortical interneurons (INs). Dysregulation of MeCP2-BRD4 ChIP regulatory axis and three-dimensional genome architecture are critically involved in the abnormal transcription in RTT INs, and JQ1 strongly rescues RTT INs by resetting the aberrant chromatin binding of BRD4 ChIP. Finally, JQ1 alleviates RTT-like phenotypes in mice. These data demonstrate that BRD4 ChIP dysregulation is a critical driver for RTT etiology and targeting BRD4 ChIP is an effective therapeutic opportunity for RTT.
Project description:Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder caused by mutations in the methyl-CpG binding protein 2 (MeCP2). Cellular heterogeneity in the brain confounds the understanding of RTT etiology. To date, how MeCP2 mutation affects defined cell types in human brain remains unclear, and effective therapeutics for RTT is lacking. Here we show that cell-type-specific transcriptome impairment and JQ1-mediated rescue in RTT cells from dorsal and ventral human forebrain organoids. We find that MeCP2 mutation severely impairs human cortical interneurons (INs). Dysregulation of MeCP2-BRD4 ChIP regulatory axis and three-dimensional genome architecture are critically involved in the abnormal transcription in RTT INs, and JQ1 strongly rescues RTT INs by resetting the aberrant chromatin binding of BRD4 ChIP. Finally, JQ1 alleviates RTT-like phenotypes in mice. These data demonstrate that BRD4 ChIP dysregulation is a critical driver for RTT etiology and targeting BRD4 ChIP is an effective therapeutic opportunity for RTT.
Project description:Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder caused by mutations in the methyl-CpG binding protein 2 (MeCP2). Cellular heterogeneity in the brain confounds the understanding of RTT etiology. To date, how MeCP2 mutation affects defined cell types in human brain remains unclear, and effective therapeutics for RTT is lacking. Here we show that cell-type-specific transcriptome impairment and JQ1-mediated rescue in RTT cells from dorsal and ventral human forebrain organoids. We find that MeCP2 mutation severely impairs human cortical interneurons (INs). Dysregulation of MeCP2-BRD4 ChIP regulatory axis and three-dimensional genome architecture are critically involved in the abnormal transcription in RTT INs, and JQ1 strongly rescues RTT INs by resetting the aberrant chromatin binding of BRD4 ChIP. Finally, JQ1 alleviates RTT-like phenotypes in mice. These data demonstrate that BRD4 ChIP dysregulation is a critical driver for RTT etiology and targeting BRD4 ChIP is an effective therapeutic opportunity for RTT.
Project description:Duplication or deficiency of the X-linked MECP2 gene reliably produces profound neurodevelopmental impairment. MECP2 mutations are almost universally responsible for Rett syndrome (RTT), and particular mutations and cellular mosaicism of MECP2 may underlie the spectrum of RTT symptomatic severity. No clinically approved treatments for RTT are currently available, but human pluripotent stem cell technology offers a platform to identify neuropathology and test candidate therapeutics. Using a strategic series of increasingly complex human stem cell-derived technologies, including human neurons, MECP2-mosaic neurospheres to model RTT female brain mosaicism, and cortical organoids, we identified synaptic dysregulation downstream from knockout of MECP2 and screened select pharmacological compounds for their ability to treat this dysfunction. Two lead compounds, Nefiracetam and PHA 543613, specifically reversed MECP2-knockout cytologic neuropathology. The capacity of these compounds to reverse neuropathologic phenotypes and networks in human models supports clinical studies for neurodevelopmental disorders in which MeCP2 deficiency is the predominant etiology.
Project description:Rett Syndrome (RTT) is a severe neurological disorder predominantly affecting females, caused by mutations in the methyl CpG binding protein 2 (MECP2) gene. Understanding the pathophysiology of RTT at a cellular and molecular level is crucial for the development of targeted therapies. Our project aims to dissect the molecular underpinnings of RTT using a novel in vitro model system based on a commercially available human neural progenitor cell line, ReNCell. We have engineered multiple distinct ReNCell lines to mimic specific genetic alterations associated with RTT, providing a robust platform for mechanistic studies and drug screening. This cell line carries a point mutation in the MECP2 gene (R133C), a common mutation in RTT patients, which alters the function of the MeCP2 protein. The model will allow us to study the impact of this mutation on neural development and function at a cellular level, providing insights into the disease's neuropathology.
Project description:Rett syndrome (RTT) is one of the most prevalent female mental disorders. De novo mutations in methyl CpG binding protein 2 (MeCP2) are a major cause of RTT. MeCP2 regulates gene expression as a transcription regulator as well as through long-range chromatin interaction. Because MeCP2 is present on the X chromosome, RTT is manifested in a X-linked dominant manner. Investigation using murine MeCP2 null models and post-mortem human brain tissues has contributed to understanding the molecular and physiological function of MeCP2. In addition, RTT models using human induced pluripotent stem cells derived from RTT patients (RTT-iPSCs) provide novel resources to elucidate the regulatory mechanism of MeCP2. Previously, we obtained clones of female RTT-iPSCs that express either wild type or mutant MECP2 due to the inactivation of one X chromosome. Reactivation of the X chromosome also allowed us to have RTT-iPSCs that express both wild type and mutant MECP2. Using these unique pluripotent stem cells, we investigated the regulation of gene expression by MeCP2 in pluripotent stem cells by transcriptome analysis. We found that MeCP2 regulates genes encoding mitochondrial membrane proteins. In addition, loss of function in MeCP2 results in de-repression of genes on the inactive X chromosome. Furthermore, we showed that each mutation in MECP2 affects a partly different set of genes. These studies suggest that fundamental cellular physiology is affected by mutations in MECP2 from very early fetal development and that a therapeutic approach targeting to unique forms of mutant MeCP2 is needed. RNA samples from normal ESCs/iPSCs, RTT-iPSCs and MeCP2 KD iPSCs were obtained. Gene expression of those cells were analyzed.
Project description:Rett syndrome (RTT) is one of the most prevalent female mental disorders. De novo mutations in methyl CpG binding protein 2 (MeCP2) are a major cause of RTT. MeCP2 regulates gene expression as a transcription regulator as well as through long-range chromatin interaction. Because MeCP2 is present on the X chromosome, RTT is manifested in a X-linked dominant manner. Investigation using murine MeCP2 null models and post-mortem human brain tissues has contributed to understanding the molecular and physiological function of MeCP2. In addition, RTT models using human induced pluripotent stem cells derived from RTT patients (RTT-iPSCs) provide novel resources to elucidate the regulatory mechanism of MeCP2. Previously, we obtained clones of female RTT-iPSCs that express either wild type or mutant MECP2 due to the inactivation of one X chromosome. Reactivation of the X chromosome also allowed us to have RTT-iPSCs that express both wild type and mutant MECP2. Using these unique pluripotent stem cells, we investigated the regulation of gene expression by MeCP2 in pluripotent stem cells by transcriptome analysis. We found that MeCP2 regulates genes encoding mitochondrial membrane proteins. In addition, loss of function in MeCP2 results in de-repression of genes on the inactive X chromosome. Furthermore, we showed that each mutation in MECP2 affects a partly different set of genes. These studies suggest that fundamental cellular physiology is affected by mutations in MECP2 from very early fetal development and that a therapeutic approach targeting to unique forms of mutant MeCP2 is needed.
Project description:Rett syndrome (RTT) is a severe neurological disorder which is mainly caused by mutations found in the X-linked gene encoding MeCP2. Despite extensive studies, the molecular functions of MeCP2 remain elusive. Here, we report that MeCP2 is a new subunit of a higher-order multiunit protein complex Rbfox/LASR and acts as a scaffold for this splicing complex. Deletion or mutation of MeCP2 leads to defects in forming MeCP2/Rbfox/LASR complex and aberrant alternative pre-mRNA splicing. Our data link RTT to an impaired function of MeCP2 in splicing control through its role in nucleating Rbfox/LASR macromolecule assembly.