Project description:Here we analyse histone modifications, DNA methylation and transcriptome profiles of SVZ-derived neural stem / progenitor cells from young adult and aged mice.
Project description:Transcriptional profiling of the microdissected SVZ from 7-month-old mice Adult neurogenesis is suppressed in the SVZ of 3xTg mice, a model of Alzheimer's disease. To better understand the underlying mechanisms of this suppression, the goals of this experiment were to compare the transcriptional profiles of the SVZ neural stem cell niche in 3xTg-AD mice versus strain controls. We used early middle-aged mice (7-months-old) rather than old mice, in order to identify genetic changes that are not caused secondarily to other degenerative changes occurring in these mice. Two-condition experiment, 3xTg vs WT SVZ. Biological replicates: 4 for each.
Project description:Transcriptional profiling of the microdissected SVZ from 7-month-old mice Adult neurogenesis is suppressed in the SVZ of 3xTg mice, a model of Alzheimer's disease. To better understand the underlying mechanisms of this suppression, the goals of this experiment were to compare the transcriptional profiles of the SVZ neural stem cell niche in 3xTg-AD mice versus strain controls. We used early middle-aged mice (7-months-old) rather than old mice, in order to identify genetic changes that are not caused secondarily to other degenerative changes occurring in these mice.
Project description:This SuperSeries is composed of the following subset Series: GSE22473: Murine postnatal subventricular zone (SVZ) neural stem cells (NSCs): Wild-type (WT) vs. Dnmt3a-null (KO) GSE22474: Genome-wide location analysis of Dnmt3a-mediated epigenetic regulation in murine postnatal subventricular zone (SVZ) neural stem cells (NSCs) [Agilent] GSE22475: Genome-wide location analysis of Dnmt3a-mediated epigenetic regulation in murine postnatal subventricular zone (SVZ) neural stem cells (NSCs) [NimbleGen] Refer to individual Series
Project description:The epigenetic mechanisms that enable specialized astrocytes to retain neurogenic competence throughout adult life are still poorly understood. Here we show that astrocytes that serve as neural stem cells (NSCs) in the adult mouse subventricular zone (SVZ) express the histone methyltransferase EZH2. This Polycomb repressive factor is required for neurogenesis independent of its role in SVZ NSC proliferation, as Ink4a/Arf-deficiency in Ezh2-deleted SVZ NSCs rescues cell proliferation, but neurogenesis remains defective. Olig2 is a direct target of EZH2, and repression of this bHLH transcription factor is critical for neuronal differentiation. Furthermore, Ezh2 prevents the inappropriate activation of genes that specify non-SVZ neuronal subtypes. In the human brain, SVZ cells including local astroglia also express EZH2, correlating with postnatal neurogenesis. Thus, EZH2 is an epigenetic regulator that distinguishes neurogenic SVZ astrocytes, orchestrating distinct and separable aspects of adult stem cell biology, which has important implications for regenerative medicine and oncogenesis. Examination of histone modifications (H3K27me3 and H3K4me3) in subventricular zone neural stem cells
Project description:Following the decline of neurogenesis at birth, progenitors of the subventricular zone (SVZ) remain mostly in a quiescent state in the adult human brain. The mechanisms that regulate this quiescent state are still unclear. Here, we isolated CD271+ progenitors from the aged human SVZ for single-cell RNA sequencing analysis. Our transcriptome data revealed the identity of progenitors of the aged human SVZ as late oligodendrocyte progenitor cells. We identified the Wnt pathway antagonist SFRP1 as a possible signal that promotes quiescence of progenitors from the aged human SVZ. Administration of WAY-316606, a small molecule that inhibits SFRP1 function, stimulates activation of neural stem cells both in vitro and in vivo under homeostatic conditions. Our data unravel a possible mechanism through which progenitors of the adult human SVZ are maintained in a quiescent state and a potential target for stimulating progenitors to re-activate.
Project description:In selected tissutal niches of the adult mouse brain, such as the subventricular zone (SVZ) underlying the lateral ventricles, neurogenesis persists thanks to a population of quiescent neural stem cells, which can be activated (aNSCs) by extrinsic stimuli to initiate proliferation and generate a neurogenic lineage consisting of transit amplifying progenitors (TAPs), neuroblasts (NBs) and newborn neurons. This process is markedly reduced during aging, which might contribute to the cognitive decline of elderly subjects. Recent studies suggest that the aged niche environment may decrease the pool of proliferating neural/stem progenitor cells (NSPCs), and hence adult neurogenesis, by causing transcriptomic changes that favour NSC quiescence over activation. The transcription factors that mediate these changes, however, remain largely unclear. We previously found that the homeobox gene Dbx2 is upregulated in NSPCs of the aged mouse SVZ and can inhibit the growth of young adult NSPC cultures. Here, we show that Dbx2 expression is downregulated by Epidermal Growth Factor Receptor signalling, which promotes NSPC proliferation and decreases in the aged SVZ. By means of transgenic NSPC lines, we also show that Dbx2 inhibits NSPC proliferation by hindering the G1/S and the G2/M transition. Furthermore, we exploit RNA sequencing of transgenic NSPCs to elucidate the transcriptional networks modulated by Dbx2. Among the top hits, we report the downregulation of several gene categories implicated in cell cycle progression. Accordingly, we find that Dbx2 function is negatively correlated with the transcriptional signatures of proliferative NSPCs (aNSCs, TAPs and early NBs). Altogether, these results point to Dbx2 as a potential molecular node relaying the extracellular anti-neurogenic input of the aged niche to the NSPC transcriptome.
Project description:Comparison of gene expression of Ink4a/Arf-/- vs Bmi1-/-;Ink4a/Arf-/- subventricular zone (SVZ) derived mouse neural stem cells (NSC) on Laminin (LM) and Fibronectin (FN) substrates.
Project description:Sox2 is expressed by neural stem and progenitor cells, and a sox2 enhancer identifies these cells in the forebrains of both fetal and adult transgenic mouse reporters. We found that an adenovirus encoding EGFP placed under the regulatory control of a 0.4 kb sox2 core enhancer selectively identified multipotential and self-renewing neural progenitor cells in dissociates of human fetal forebrain. Gene expression analysis of E/sox2:EGFP-sorted neural progenitor cells, normalized to the unsorted forebrain dissociates from which they derived, revealed marked overexpression of genes within the notch and wnt pathways, and identified multiple elements of each pathway that appear selective to human neural progenitors. We used adenoviral E/sox2:EGFP to transduce dissociates of the second trimester human ventricular zone (VZ)/ subventricular zone (SVZ), followed by EGFP-directed fluorescence-activated cell sorting (FACS). The sox2 isolates and unsorted controls from different gestational ages (16-19 wks, n=4) were then subject to RNA extraction and hybridization on Affymetrix microarrays.
Project description:We have developed spontaneous genetically engineered GBM mouse models from two distinct cells of origin: subventricular zone neural stem cells (SVZ; Nestin-creERT2) and oligodendrocyte lineage progenitor cells (OPC; NG2-creERTM). These tumors are biologically separable and are reflective of their lineage of origin.