RNA-seq of hybrid mouse female NSCs for X inactivation analysis
Ontology highlight
ABSTRACT: In mammals, dosage compensation for the sex chromosomes is achieved by transcriptional silencing of one of the two X chromosomes in females. The inactive X adopts a particular epigenetic state, characterised by specific histones, histone marks, DNA methylation and 3D chromatin structure. As allelic resolution with short-read sequencing is limited, we do not yet have chromosome-wide phased methylomes of the active and inactive X. In this study, we obtained such complete X methylomes in mouse placenta and neural stem cells (NSCs) via long-read nanopore sequencing. This accession corresponds to the RNA-seq for the NSCs.
Project description:Purpose: The aim of this study is (1) to identify the chromatin occupancy of the epigenetic regulator Smchd1 in neural stem cells (NSCs) derived from E14.5 mouse brain; (2) to profile key epigenetic marks H3K4me3, H3K27me3 and DNA methylation in wild type and Smchd1 null NSCs; (3) to identify the chromatin occupancy of Ctcf in wild type and Smchd1 null NSCs. Methods: Chromatin immunoprecipitation for Smchd1, H3K4me3, H3K27me3 and Ctcf was performed essentially as in (Nelson et al. 2006). Briefly, nuclei were isolated from formaldehyde crosslinked NSCs and chromatin was fragmented by sonication. Chromatin immunoprecipitation was performed with corresponding antibodies for Smchd1, H3K4me3 and H3K27me3. DNA was extracted from the immunoprecipitated fraction following reverse-crosslinking. Isolated DNA was used to generate sequencing libraries with Illumina's TruSeq DNA Sample Preparation Kit or Ovation Ultralow system (NuGen) according to manufacturer's instruction. Libraries were pooled and sequenced on the Illumina HiSeq 2000 platform for 100 bp single-end reads. Image analysis was performed in real time by the HiSeq Control Software (HCS) v1.4.8 and Real Time Analysis (RTA) v1.12.4.2, running on the instrument computer. Real-time base calling on the HiSeq instrument computer was performed with the RTA software. Illumina CASAVA1.8 pipeline was used to generate the sequence data. To examine the level of DNA methylation, genomic DNA was extracted using an AllPrep DNA/RNA Mini Kit (Qiagen) and methylated DNA was isolated via binding to the methyl-CpG binding domain of human MBD2 protein coupled beads using the MethylMiner methylated DNA enrichment kit (Life Technologies) according to the manufacturer’s instructions. Isolated DNA was used to generate sequencing libraries as for the ChIP-seq experiment with Illumina’s TruSeq DNA Sample Preparation Kit according to manufacturer's instruction and sequenced on the Illumina HiSeq 2000 platform for 49 bp single-end reads. Sequencing analysis was performed as described for the ChIP-seq experiments. Chromatin occupancy of the epigenetic regulator Smchd1 in neural stem cells (NSCs) derived from E14.5 mouse brain was determined by Smchd1 ChIP-seq. Enrichment of H3K4me3 and H3K27me3 in wild type and Smchd1 null NSCs were assessed by H3K4me3 and H3K27me3 ChIP-seq, respectively. DNA methylation in wild type and Smchd1 null NSCs was assessed by MBD-seq. Chromatin occupancy of Ctcf in wild type and Smchd1 null NSCs was determined by by Ctcf ChIP-seq.
Project description:Purpose: The aim of this study is to identify genes that are under the transcriptional control of the epigenetic regulator Smchd1 in neural stem cells (NSCs) derived from E14.5 mouse brain Methods: Total RNA was extracted using an AllPrep DNA/RNA Mini Kit (Qiagen) from cultured neural stem cells derived from male mouse E14.5 brains either wild-type or null for Smchd1. 1 µg total RNA was used to generate sequencing libraries for whole transcriptome analysis with Illumina’s TruSeq RNA Sample Preparation Kit v2 as per standard protocols. Libraries were sequenced on HiSeq 2000 with Illumina TruSeq SBS Kit v3-HS reagents as either 100 bp single-end or paired-end reads at the Australian Genome Research Facility (AGRF), Melbourne. Reads were aligned to the mouse reference genome mm10 and mapped to known genomic features at the gene level using the Rsubread package (version 1.10.5) (Liao et al. 2013). Mapped reads were then summarized into gene-level counts using FeatureCounts (Liao et al. 2014). Total RNA was extracted and purified from each cell line and their transcriptomes analyzed by RNA-Seq.
Project description:In this study we sought to determine the effect of overexpressing the SUMOylation E2 conjugase Ubc9 on the response of murine Neural Stem Cells (NSCs) to oxygen-glucose-deprivation and restoration of oxygen/glucose (OGD/ROG). We established stably-expandable lines of NSCs from the subventricular zones (SVZ) of adult wild-type mice (WT NSCs) and Ubc9-overexpressing mice (Ubc9 NSCs) and profiled their transcriptional changes in response to OGD/ROG as well as in response to differentiation.
Project description:Using long-read nanopore sequencing, we obtained chromosome-wide phased methylomes of the active and inactive X in mouse placenta and neural stem cells (NSCs), overcoming the limitations if short-read bisulfite sequencing in allelic resolution. We also conducted quantitative analysis of methylation properties like symmetry and entropy, providing a more comprehensive view of epigenetic silencing in X chromosome inactivation. We also resolved the allele-specific genetics and epigenetics of structural macrosatellite Dxz4 and other repeats.
Project description:CASPASE-3 (CASP3) is well known for its proteolytic function that mediates multiple key cell death-initiated processes and other related cellular processes. However, the possibility that CASP3 may also possess important additional non-catalytic functions in mammalian cells has remained largely unexplored. We now report the results of CASP3 knockdown, rescue, proteomic analysis and flow cytometry experiments initially in normal and malignant human mammary cells and later shown to extent to all other human cell types tested. The results reveal a new role of the CASP3 prodomain in regulating the cell cycle progression, survival, proliferation, and protein aggregate accumulation in all cells tested. The generality of these findings suggests that the ancestral pro-survival role of CASP3 in yeast persisted throughout evolution via a conservation of its prodomain, predating its later acquisition of an inherent catalytic property and subsequently preserved cell death control functions.
Project description:The functional coupling between alternative pre-mRNA splicing (AS) and the mRNA quality control mechanism called nonsense-mediated decay (NMD) has been shown to modulate the expression of numerous genes. Previous studies have identified several examples of this regulation in developing neurons. However, the systems-level effects of AS-NMD in this context have been poorly understood. To this end, we performed a longitudinal analysis of gene expression in mouse embryonic stem cells undergoing induced neuronal differentiation, as well as primary neural cells. To improve the detection of NMD-sensitive splice forms, some of the samples were treated with the translation inhibitor cycloheximide or separated into nuclear and cytoplasmic fractions. Our analyses uncovered hundreds of AS-NMD events with significant potential to regulate their host genes. Notably, these events were significantly overrepresented in developmentally downregulated genes. Particularly strong enrichment was detected for alternative cassette exons that trigger NMD upon their inclusion into mature mRNA. Overall, this study extends our understanding of the molecular mechanisms underlying neuronal differentiation and highlights the importance of post-transcriptional regulation gene expression in orchestrating this intricate process.
Project description:The ability of high-risk neuroblastoma to survive unfavorable growth conditions and multimodal therapy is hypothesized to result from a phenomenon known as reversible adaptive plasticity (RAP). RAP is a novel phenomenon enabling neuroblastoma cells to transition between a proliferative anchorage dependent (AD) state and a slow growing anoikis-resistant anchorage independent (AI) state. We used microarrays to investigate the global gene expression profiles in AD and AI cells, and to identify the differential expressed genes within signaling pathways contributing to the reversible adaptive plasticity between AD and AI cells. Comparison of microarray data from AD cells (n=4 independent cultures) versus AI cells (n=4 independent cultures) were performed using Partek Genomics Suite 6.5. Differentially expressed genes with an FDR M-bM-^IM-$5% and a fold-change M-bM-^IM-%1.5 were selected for pathway analysis.
Project description:To investigate the effects of ZIKV infection or ZIKV-NS4B-transduction on the global proteome scale at early stages of hNPC differentiation into neurons, hNPC cells were infected with ZIKV (Asian strain: H/PF/2013; MOI=0.01) or transduced with ZIKV-NS4B or HCV-NS4B and one day later cells were either left under proliferative conditions or neuronal differentiation was induced with ROCK inhibitors treatment and growth factors withdrawals. Five days later samples were harvested and processed for quantitative label-free proteomics.
Project description:Here we performed a microarray experiment on samples of adherent cultures of mouse neural stem cells (NS5 cell line) expressing an inducible version of the transcription factor MyT1 (MyT1-V5 TetON) under normal growth conditions and after 4 hours of treatment by doxycyline. This resulted in the generation of a genome-wide mRNA expression pattern and quantification for these cells in the two conditions.