Brain-specific transcriptome analysis in MECP2 transgenic monkeys
Ontology highlight
ABSTRACT: We have performed gene expression profiling of the MECP2 transgenic monkey, taking advantage of recently completed genome sequencing for the cynomolgus monkey. We found interesting changes in the pattern of alternative splicing of many genes, including genes coding synaptic proteins (e.g., neurexin-3 and Shank-3) and metabolism-related proteins, as compared to the wild-type monkey. This study provides important information for understanding the impact of disease-related gene on brain development. Examination of transcriptome in brain tissues of wild-type and MECP2 transgenic monkeys.
Project description:The goal of this study was to characterize a novel Mecp2 allele in the laboratory rat, a distinct rodent species from the laboratory mouse with unique features. The allele was created by zinc finger-nuclease (ZFN) targeting (SAGE/Horizon) of the X-linked gene, Methyl-CpG-Binding Protein 2 (Mecp2), resulting in normal Mecp2 RNA abundance, but absent protein in male rats as expected due to the presence of only one copy of mutant Mecp2, and an approximate 50% reduction in female rats as expected from animals that harbor one wild-type copy and one mutant copy of Mecp2. Behavioral characterization of female rats with the Mecp2 ZFN allele and wild-type littermates was conducted, and Mecp2 ZFN/+ female rats showed behavioral phenotypes that were consistent with disease-like features present during the early stages of disease onset in the neurological disorder Rett syndrome. The goal of conducting RNAseq studies was to compare existing gene expression alterations in the Mecp2 rat with one of the most widely studied Mecp2 mouse model. Hypothalami were obtained from males with complete loss of MeCP2 (ZFN/y) and wild-type littermate male rats for RNA-seq studies. Common and unique gene expression alterations among the Mecp2 rodents that were then tested in human Rett and control postmortem brain revealed the benefit of combining findings from both models, suggesting the predictive validity of this approach for future studies for the identification of potential preclinical outcome measures. QPCR validation in an independent set of rats was conducted with a subset of genes from the Mecp2 ZFN rat RNA-seq data as an additional control measure. Taken together, these findings demonstrate that the Mecp2 rat model is a complementary tool with unique features for the study of RTT and highlight the potential benefit of cross-species analyses in identifying potential disease-relevant preclinical outcome measures. Transcriptional profiles of hypothalamic samples obtained from male rats haboring a novel zinc-finger nuclease Mecp2 loss-of-function allele and corresponding wild-type littermate rats were generated using RNA-seq
Project description:To determine whether the miRNA expression profile is altered by MeCP2, we performed Solexa-based RNA sequencing(RNA-seq) to assess global changes in the expression pattern of miRNAs caused by the loss of MeCP2 in mecp2 null (knockout[KO]) mice (Chen et al., 2001). Hippocampus miRNA profiles of 30-day old wild type (WT) and MeCP2-/y mice were generated by deep sequencing using Illumina HiSeq 2000
Project description:Although the function of DNA methylation in gene promoter regions is well established in transcriptional repression, the function of the evolutionarily conserved widespread distribution of DNA methylation in gene body regions remains incompletely understood. Here, we show that DNA methylation is enriched in included alternatively spliced exons (ASEs) and inhibiting DNA methylation results in aberrant splicing of ASEs. The methyl-CpG binding protein MeCP2 is enriched in included ASEs, particularly those that are also highly DNA methylated, and inhibition of DNA methylation disrupts specific targeting of MeCP2 to exons. Interestingly, ablation of MeCP2 results in increased nucleosome acetylation and aberrant skipping events of ASEs. We further show that inhibition of histone deacetylases leads to a highly significant overlap of exon skipping events caused by knocking-down MeCP2. Together, our data indicate that intragenic DNA methylation operates in exon definition to modulate alternative splicing and can enhance exon recognition via recruitment of the multifunctional protein MeCP2, which thereby maintains local histone hypoacetylation through its established interaction with HDACs. MeCP2 ChIP-Seq in IMR90 and HCT116 cells
Project description:Purpose: Investigate effects of high salt on human macrophage activation Methods: Human monocytes-derived macrophages were treated by additional 51mM NaCl for 24 hours (NaCl groups) or not (Control groups). mRNA profiles were generated by RNA-Seq, in triplicate, using Ion proton(Life tech). qRT–PCR validation was performed using SYBR Green assays. Results: High salt significantly promotes pro-inflammatory gene expressions,while suppresses the expressions of anti-inflammatory genes and pro-endocytic genes in human macrophages. Conclusions: Our results identify a novel macrophage activation state, M(Na), and high salt as a potential environmental risk factor for lung inflammation through the induction of M(Na) Human monocytes-derived macrophages were treated by additional 51mM NaCl for 24 hours (NaCl groups) or not (Control groups). mRNA profiles were generated by RNA-Seq, in triplicate, using Ion proton(Life tech). qRT–PCR validation was performed using SYBR Green assays.
Project description:We have performed gene expression profiling of the MECP2 transgenic monkey, taking advantage of recently completed genome sequencing for the cynomolgus monkey. We found interesting changes in the pattern of alternative splicing of many genes, including genes coding synaptic proteins (e.g., neurexin-3 and Shank-3) and metabolism-related proteins, as compared to the wild-type monkey. This study provides important information for understanding the impact of disease-related gene on brain development.
Project description:Proteomics on B. thuringiensis CT_43 cells in GYS medium. Two biological replicate cell samples were collected at time points of 7 h, 9 h, 13 h and 22 h, respectively. The crude proteins were purified using the ReadyPrep 2-D Cleanup Kit, underwent the reductive alkylation, tryptically digested, and were labeled with 8-plex iTRAQ reagents as follows: 7 h-1, 113; 7 h-2, 114; 9 h-1, 115; 9 h-2, 116; 13 h-1, 117; 13 h-2, 118; 22 h-1, 119; and 22 h-2, 121. The labeled samples were pooled and resolved into 12 fractions, which were loaded onto LC-MSMS.
Project description:The postnatal neurodevelopmental disorder Rett syndrome (RTT) is caused by mutations in the gene encoding Methyl-CpG-binding Protein 2 (MeCP2). Despite decades of research, it remains unclear how MeCP2 actually regulates transcription or why RTT features appear only 6-18 months after birth. We examined MeCP2 binding to methylated cytosine in the CH context (mCH, where H = A, C, or T) in the adult mouse brain and found that MeCP2 binds these mCH sites, influencing nucleosome positioning and transcription. Strikingly, this pattern is unique to the mature nervous system, as it requires the increase in mCH after birth to reveal differences in MeCP2 binding to mCG, mCH, and non-methylated DNA elements. This study provides insight into the molecular mechanism governing MeCP2 targeting and how this targeting might contribute to the delayed onset of RTT symptoms. mRNA-Seq were conducted from 7-week-old hypothalamus from MeCP2 knockout mice and their age and genetic background matched wild types control mice. Additonal mRNA-Seq were conducted from 7-week-old hypothalamus from MeCP2 transgenic mice and their age and genetic background matched wild types control mice.
Project description:Mutations in methyl-CpG-binding protein 2 (MeCP2), a major epigenetic regulator, are the predominant cause of Rett syndrome, an X-linked neurodevelopmental disorder. We previously found that Mecp2-null microglia are functionally impaired, and that engraftment of wild-type monocytes into the brain of Mecp2-deficient mice attenuates pathology. In this study we show that Mecp2 is expressed in macrophage and monocyte populations throughout the body, and is indispensable for their transcriptional regulation in multiple contexts. We demonstrate that Mecp2-null mice progressively lose or are chronically deficient in several macrophage populations and resident monocytes. Postnatal re-expression of Mecp2 driven by a tamoxifen-inducible CX3CR1 promoter significantly increased the lifespan of otherwise Mecp2-null mice, suggesting that epigenetic regulation of macrophage function by Mecp2 significantly contributes to pathology. RNA-Seq of acutely isolated microglia and peritoneal macrophages (to our knowledge, the first cell-specific RNA-Seq analysis comparing Mecp2-null and wild type cells of any kind) revealed significantly increased transcription of glucocorticoid- and hypoxia-signaling genes in Mecp2-null cells compared to that in their wild-type counterparts, suggesting that Mecp2 functions as a repressor of these pathways. Furthermore, in-vitro and in vivo validation studies demonstrated that the absence of Mecp2 is associated with cell-intrinsic dysfunction of signaling underlying inflammatory activation, suggesting that Mecp2 is important for regulation of specific macrophage gene-expression programs in response to stimuli and stressors. Our findings demonstrate a fundamental role for Mecp2 in the regulation of macrophage functions, which may provide a link to pathologies in Rett syndrome across multiple organs. Mecp2-null microglia and resident peritoneal macrophages from 10-12 week old mice were acutely isolated via AutoMACS, total RNA collected, and analyzed via RNA-Seq to compare for transcriptional differences in microglia and macrophages in the absence of Mecp2.
Project description:In mammals, sex differentiation of primordial germ cells (PGCs) is determined by extrinsic cues from the environment1. In female PGCs, expression of Stimulated by retinoic acid 8 (Stra8) and meiosis are induced in response to retinoic acid (RA) provided by the mesonephroi2-4. Given the widespread role of RA signaling during development8,9, the molecular mechanism specifying the competence of PGCs to timely express Stra8 and enter meiosis are unknown2,10. Here we identify gene dosage dependent roles in PGC development for Ring1 and Rnf2, two central components of the Polycomb Repressive Complex 1 (PRC1)11,13. Both paralogs are essential for PGC development between day 10.5 and 11.5 of gestation. Rnf2 is subsequently required in female PGCs for maintaining high levels of Oct4 and Nanog expression6, and for preventing premature induction of meiotic gene expression and entry into meiotic prophase. Chemical inhibition of RA signaling partially suppresses precocious Oct4 down-regulation and Stra8 activation in Rnf2-deficient female PGCs. Chromatin immunoprecipitation analyses show that Stra8 is a direct target of PRC1 and PRC2 in PGCs. These data demonstrate the importance of PRC1 gene dosage in PGC development and in coordinating the timing of sex differentiation of female PGCs by antagonizing extrinsic RA signaling. Gene expression of mouse primordial germ cells was analysed using RNAseq method. Primodial germ cells were purified from embryos carrying Oct4(-delta-PE)-GFP transgene by FACS.
Project description:Metazoan development depends on accurate execution of differentiation programs that allow pluripotent stem cells to adopt specific fates. Differentiation is brought about by global changes to chromatin architecture and transcriptional networks, yet whether other regulatory events support cell fate determination is less well understood. Using human embryonic stem cell and Xenopus models, we identified the vertebrate-specific ubiquitin ligase Cul3KBTBD8 as an essential regulator of neural crest specification. Cul3KBTBD8 monoubiquitylates NOLC1 and its paralog TCOF1, whose mutation underlies the craniofacial disorder Treacher Collins Syndrome that is characterized by a loss of cranial neural crest cells. Ubiquitylation of NOLC1 and TCOF1 drives formation of a platform that connects RNA polymerase I with ribosome modification enzymes, thereby altering the translational program of differentiating cells to support the generation of neural crest cells. We conclude that the dynamic regulation of ribosome function is an important feature of cell fate determination. Ribosome profiling and mRNA-Seq