Project description:Histone 3 Lysine 9 (H3K9) methylation is known to be associated with pericentric heterochromatin and important in genomic stability. In this study, we show that trimethylation at H3K9 (H3K9me3) is enriched in an adult neural stem cell niche- the subventricular zone (SVZ) on the walls of the lateral ventricle in both rodent and non-human primate baboon brain. Previous studies have shown that there is significant correlation between baboon and human regarding genomic similarity and brain structure, suggesting that findings in baboon are relevant to human. To understand the function of H3K9me3 in this adult neurogenic niche, we performed genome-wide analyses using ChIP-Seq (chromatin immunoprecipitation and deep-sequencing) and RNA-Seq for in vivo SVZ cells purified from baboon brain. Through integrated analyses of ChIP-Seq and RNA-Seq, we found that H3K9me3-enriched genes associated with cellular maintenance, post-transcriptional and translational modifications, signaling pathways, and DNA replication are expressed, while genes involved in axon/neuron, hepatic stellate cell, or immune-response activation are not expressed. As neurogenesis progresses in the adult SVZ, cell fate restriction is essential to direct proper lineage commitment. Our findings highlight that H3K9me3 repression in undifferentiated SVZ cells is engaged in the maintenance of cell type integrity, implicating a role for H3K9me3 as an epigenetic mechanism to control cell fate transition within this adult germinal niche. SVZ H3K9me3 ChIP-seq profile of an adult baboon subventricular zone was generated by deep sequencing with Illumina HiSeq2000
Project description:Histone 3 Lysine 9 (H3K9) methylation is known to be associated with pericentric heterochromatin and important in genomic stability. In this study, we show that trimethylation at H3K9 (H3K9me3) is enriched in an adult neural stem cell niche- the subventricular zone (SVZ) on the walls of the lateral ventricle in both rodent and non-human primate baboon brain. Previous studies have shown that there is significant correlation between baboon and human regarding genomic similarity and brain structure, suggesting that findings in baboon are relevant to human. To understand the function of H3K9me3 in this adult neurogenic niche, we performed genome-wide analyses using ChIP-Seq (chromatin immunoprecipitation and deep-sequencing) and RNA-Seq for in vivo SVZ cells purified from baboon brain. Through integrated analyses of ChIP-Seq and RNA-Seq, we found that H3K9me3-enriched genes associated with cellular maintenance, post-transcriptional and translational modifications, signaling pathways, and DNA replication are expressed, while genes involved in axon/neuron, hepatic stellate cell, or immune-response activation are not expressed. As neurogenesis progresses in the adult SVZ, cell fate restriction is essential to direct proper lineage commitment. Our findings highlight that H3K9me3 repression in undifferentiated SVZ cells is engaged in the maintenance of cell type integrity, implicating a role for H3K9me3 as an epigenetic mechanism to control cell fate transition within this adult germinal niche.
Project description:This data set consists of tissue-specific RNA-seq reads from 14 different tissues from a single female adult olive baboon (Papio anubis): bone marrow, brain cerebellum, brain frontal cortex, brain pituitary, brain temporal lobe, colon, heart, kidney, liver, lymph node, spleen, lung, skeletal muscle and thymus. The data set was generated by the non-human primate reference transcriptome resource (NHPRTR) project (http://nhprtr.org/), and was first made public on 14 Jan 2014.
Project description:Histone 3 lysine 4 trimethylation (H3K4me3) is known to be associated with transcriptionally active or poised genes and required for postnatal neurogenesis within the subventricular zone (SVZ) in the rodent model. Previous comparisons have shown significant correlation between baboon (Papio anubis) and human brain. In this study, we demonstrate that chromatin activation mark H3K4me3 is present in undifferentiated progenitor cells within the SVZ of adult baboon brain. To identify the targets and regulatory role of H3K4me3 within the baboon SVZ, we developed a technique to purify undifferentiated SVZ cells while preserving the endogenous nature without introducing culture artifact to maintain the in vivo chromatin state for genome-wide studies (ChIP-Seq and RNA-Seq). Overall, H3K4me3 is significantly enriched for genes involved in cell cycle, metabolism, protein synthesis, signaling pathways, and cancer mechanisms. Additionally, we found elevated levels of H3K4me3 in the MRI-classified SVZ-associated Glioblastoma Multiforme (GBM), which has a transcriptional profile that reflects the H3K4me3 modifications in the undifferentiated progenitor cells of the baboon SVZ. Our findings highlight the importance of H3K4me3 in coordinating distinct networks and pathways for life-long neurogenesis, and suggest that subtypes of GBM could occur, at least in part, due to aberrant H3K4me3 epigenetic regulation. SVZ H3K4me3 ChIP-seq profile of an adult baboon brain was generated by deep sequencing with Illumina HiSeq 2000.
Project description:Histone 3 lysine 4 trimethylation (H3K4me3) is known to be associated with transcriptionally active or poised genes and required for postnatal neurogenesis within the subventricular zone (SVZ) in the rodent model. Previous comparisons have shown significant correlation between baboon (Papio anubis) and human brain. In this study, we demonstrate that chromatin activation mark H3K4me3 is present in undifferentiated progenitor cells within the SVZ of adult baboon brain. To identify the targets and regulatory role of H3K4me3 within the baboon SVZ, we developed a technique to purify undifferentiated SVZ cells while preserving the endogenous nature without introducing culture artifact to maintain the in vivo chromatin state for genome-wide studies (ChIP-Seq and RNA-Seq). We identified that H3K4me3 is significantly enriched for genes involved in cell cycle, cell signaling, nervous system development, metabolism, and ribosomal biogenesis. Among these genes, RNA-Seq identified that genes associated with cellular signaling/maintenance, DNA replication, metabolism, and protein synthesis are expressed. We found that 72% of H3K4me3-enriched genes in undifferentiated SVZ cells are expressed (1913 genes are detectable by RNA-Seq; 2663 genes enriched with H3K4me3 by ChIP-Seq). On the other hand, 750 out of total 2663 H3K4me3-enriched genes are not detectable by RNA-Seq, suggesting 28% of genes in SVZ are poised for activation. RNA-seq profiles were generated from adult baboon subventricular zone primary cells by paired-end deep sequencing with an Illumina HiSeq 2000. RNA-Seq Analysis: Total RNA was extracted from purified baboon SVZ cells using TRIzol reagent, and sequencing libraries were generated with the Illumina RNA-Seq library kit. Paired-end RNA-deepSeq (76 base pair; >300 million tag reads; 269,081,636 mapped reads) were aligned to hg19. DESeq was used to normalize raw read counts, and Cufflink reports read counts and estimated FPKM (fragments per kilobase of exon per million fragments mapped; http://cufflinks.cbcb.umd.edu/faq.html#fpkm). Genes with expression values >1 FPKM were considered for subsequent analyses.