Similar Datasets
Project description:The functional and transcriptional maturation of neurons is a prolonged process that extends well beyond mitotic exit and terminal fate commitment of progenitors. The differentiation of cerebellar granule neurons (CGNs) in the postnatal mouse cerebellum provides a useful model to identify chromatin mechanisms that orchestrate temporal changes in transcription as postmitotic CGNs mature. Here we report that CGN maturation is associated with dynamic changes in the genomic distribution of histone H3 lysine 27 trimethylation (H3K27me3), a modification best known for its role in repressing alternative fates during cell specification. H3K27me3 is gained rapidly in newly postmitotic CGNs at progenitor-expressed genes that are repressed in neurons. H3K27me3 is lost more gradually at the promoters of a subset of neuronal genes that are transcriptionally induced upon CGN maturation. The loss of H3K27me3 is facilitated by the lysine demethylase KDM6B, and genes that are induced in maturing CGNs show impaired expression in the cerebellum of conditional KDM6B knockout mice. Genes that lose H3K27me3 gain H3K27 acetylation and binding of the pro-maturation ZIC1/2 transcription factors, suggesting that developmental loss of H3K27me3 may be required to permit the onset of transcriptional maturation. Interestingly, pharmacological inhibition of the H3K27 methyltransferase EZH2 in early postmitotic CGNs not only blocked the repression of progenitor genes but also impaired the induction of mature CGN genes. These data show that regulation of H3K27me3 functions in developing postmitotic neurons beyond the period of cell fate commitment to regulate the dynamics of gene expression programs that underlie functional neuronal maturation.
2022-10-11 | GSE212440 | GEO
Project description:The functional and transcriptional maturation of neurons is a prolonged process that extends well beyond mitotic exit and terminal fate commitment of progenitors. The differentiation of cerebellar granule neurons (CGNs) in the postnatal mouse cerebellum provides a useful model to identify chromatin mechanisms that orchestrate temporal changes in transcription as postmitotic CGNs mature. Here we report that CGN maturation is associated with dynamic changes in the genomic distribution of histone H3 lysine 27 trimethylation (H3K27me3), a modification best known for its role in repressing alternative fates during cell specification. H3K27me3 is gained rapidly in newly postmitotic CGNs at progenitor-expressed genes that are repressed in neurons. H3K27me3 is lost more gradually at the promoters of a subset of neuronal genes that are transcriptionally induced upon CGN maturation. The loss of H3K27me3 is facilitated by the lysine demethylase KDM6B, and genes that are induced in maturing CGNs show impaired expression in the cerebellum of conditional KDM6B knockout mice. Genes that lose H3K27me3 gain H3K27 acetylation and binding of the pro-maturation ZIC1/2 transcription factors, suggesting that developmental loss of H3K27me3 may be required to permit the onset of transcriptional maturation. Interestingly, pharmacological inhibition of the H3K27 methyltransferase EZH2 in early postmitotic CGNs not only blocked the repression of progenitor genes but also impaired the induction of mature CGN genes. These data show that regulation of H3K27me3 functions in developing postmitotic neurons beyond the period of cell fate commitment to regulate the dynamics of gene expression programs that underlie functional neuronal maturation.
2022-10-11 | GSE212439 | GEO
Project description:The functional and transcriptional maturation of neurons is a prolonged process that extends well beyond mitotic exit and terminal fate commitment of progenitors. The differentiation of cerebellar granule neurons (CGNs) in the postnatal mouse cerebellum provides a useful model to identify chromatin mechanisms that orchestrate temporal changes in transcription as postmitotic CGNs mature. Here we report that CGN maturation is associated with dynamic changes in the genomic distribution of histone H3 lysine 27 trimethylation (H3K27me3), a modification best known for its role in repressing alternative fates during cell specification. H3K27me3 is gained rapidly in newly postmitotic CGNs at progenitor-expressed genes that are repressed in neurons. H3K27me3 is lost more gradually at the promoters of a subset of neuronal genes that are transcriptionally induced upon CGN maturation. The loss of H3K27me3 is facilitated by the lysine demethylase KDM6B, and genes that are induced in maturing CGNs show impaired expression in the cerebellum of conditional KDM6B knockout mice. Genes that lose H3K27me3 gain H3K27 acetylation and binding of the pro-maturation ZIC1/2 transcription factors, suggesting that developmental loss of H3K27me3 may be required to permit the onset of transcriptional maturation. Interestingly, pharmacological inhibition of the H3K27 methyltransferase EZH2 in early postmitotic CGNs not only blocked the repression of progenitor genes but also impaired the induction of mature CGN genes. These data show that regulation of H3K27me3 functions in developing postmitotic neurons beyond the period of cell fate commitment to regulate the dynamics of gene expression programs that underlie functional neuronal maturation.
2022-10-11 | GSE212438 | GEO
Project description:The functional and transcriptional maturation of neurons is a prolonged process that extends well beyond mitotic exit and terminal fate commitment of progenitors. The differentiation of cerebellar granule neurons (CGNs) in the postnatal mouse cerebellum provides a useful model to identify chromatin mechanisms that orchestrate temporal changes in transcription as postmitotic CGNs mature. Here we report that CGN maturation is associated with dynamic changes in the genomic distribution of histone H3 lysine 27 trimethylation (H3K27me3), a modification best known for its role in repressing alternative fates during cell specification. H3K27me3 is gained rapidly in newly postmitotic CGNs at progenitor-expressed genes that are repressed in neurons. H3K27me3 is lost more gradually at the promoters of a subset of neuronal genes that are transcriptionally induced upon CGN maturation. The loss of H3K27me3 is facilitated by the lysine demethylase KDM6B, and genes that are induced in maturing CGNs show impaired expression in the cerebellum of conditional KDM6B knockout mice. Genes that lose H3K27me3 gain H3K27 acetylation and binding of the pro-maturation ZIC1/2 transcription factors, suggesting that developmental loss of H3K27me3 may be required to permit the onset of transcriptional maturation. Interestingly, pharmacological inhibition of the H3K27 methyltransferase EZH2 in early postmitotic CGNs not only blocked the repression of progenitor genes but also impaired the induction of mature CGN genes. These data show that regulation of H3K27me3 functions in developing postmitotic neurons beyond the period of cell fate commitment to regulate the dynamics of gene expression programs that underlie functional neuronal maturation.
2023-04-25 | GSE218685 | GEO
Project description:The functional and transcriptional maturation of neurons is a prolonged process that extends well beyond mitotic exit and terminal fate commitment of progenitors. The differentiation of cerebellar granule neurons (CGNs) in the postnatal mouse cerebellum provides a useful model to identify chromatin mechanisms that orchestrate temporal changes in transcription as postmitotic CGNs mature. Here we report that CGN maturation is associated with dynamic changes in the genomic distribution of histone H3 lysine 27 trimethylation (H3K27me3), a modification best known for its role in repressing alternative fates during cell specification. H3K27me3 is gained rapidly in newly postmitotic CGNs at progenitor-expressed genes that are repressed in neurons. H3K27me3 is lost more gradually at the promoters of a subset of neuronal genes that are transcriptionally induced upon CGN maturation. The loss of H3K27me3 is facilitated by the lysine demethylase KDM6B, and genes that are induced in maturing CGNs show impaired expression in the cerebellum of conditional KDM6B knockout mice. Genes that lose H3K27me3 gain H3K27 acetylation and binding of the pro-maturation ZIC1/2 transcription factors, suggesting that developmental loss of H3K27me3 may be required to permit the onset of transcriptional maturation. Interestingly, pharmacological inhibition of the H3K27 methyltransferase EZH2 in early postmitotic CGNs not only blocked the repression of progenitor genes but also impaired the induction of mature CGN genes. These data show that regulation of H3K27me3 functions in developing postmitotic neurons beyond the period of cell fate commitment to regulate the dynamics of gene expression programs that underlie functional neuronal maturation.
2023-04-28 | GSE230712 | GEO
Project description:Dendrite and synapse development are critical for establishing appropriate neuronal circuits, and disrupted timing of these events can alter connectivity leading to disordered neural function. In early postnatal development of cerebellar granule neurons (CGNs), the expression of many genes is temporally regulated. Further, NFI (Nuclear Factor I) proteins have been shown to play important roles in the regulation of gene expression in developing CGNs. To identify NFI-regulated genome-wide targets involved in late maturation of mouse CGNs, we performed two groups of microarray expression analysis: (1) temporal expression arrays using 1.5 and 6 day cultures of mouse CGNs representing immature and more mature CGNs, respectively, which identified 844 Temporal-Up or Down genes; and (2) NFI-regulated genes in 6 day CGN cultures that were infected at the time of plating with lentiviral vectors expressing either NFI dominant repressor (NFI-EnR) or EnR control protein. This identified 686 NFI-Up (NFI-EnR down-regulated) or NFI-Down (NFI-EnR up-regulated) genes. Overlap analysis identified 212 temporal genes that were regulated by NFI. These results indicated that NFI plays a pivotal role in the regulation of late CGN maturation. For temporal arrays, mouse CGN progenitors were purified from P6 mouse cerebellum and cultured for either 1.5 or 6 days. Three biological replicates were analyzed for each time point. For NFI arrays, CGN progenitors from P6 mice were transduced upon plating with either NFI-EnR or EnR control lentivirus and cultured 6 days. Four pairs of biological replicates were performed.
2012-11-07 | E-GEOD-42018 | biostudies-arrayexpress
Project description:Biologically relevant large-scale computational models currently represent one of the main methods in neuroscience for studying information processing primitives of brain areas. However, biologically realistic neuron models tend to be computationally heavy and thus prevent these models from being part of brain-area models including thousands or even millions of neurons. The cerebellar input layer represents a canonical example of large scale networks. In particular, the cerebellar granule cells, the most numerous cells in the whole mammalian brain, have been proposed as playing a pivotal role in the creation of somato-sensorial information representations. Enhanced burst frequency (spiking resonance) in the granule cells has been proposed as facilitating the input signal transmission at the theta-frequency band (4-12 Hz), but the functional role of this cell feature in the operation of the granular layer remains largely unclear. This study aims to develop a methodological pipeline for creating neuron models that maintain biological realism and computational efficiency whilst capturing essential aspects of single-neuron processing. Therefore, we selected a light computational neuron model template (the adaptive-exponential integrate-and-fire model), whose parameters were progressively refined using an automatic parameter tuning with evolutionary algorithms (EAs). The resulting point-neuron models are suitable for reproducing the main firing properties of a realistic granule cell from electrophysiological measurements, including the spiking resonance at the theta-frequency band, repetitive firing according to a specified intensity-frequency (I-F) curve and delayed firing under current-pulse stimulation. Interestingly, the proposed model also reproduced some other emergent properties (namely, silent at rest, rheobase and negligible adaptation under depolarizing currents) even though these properties were not set in the EA as a target in the fitness function (FF), proving that these features are compatible even in computationally simple models. The proposed methodology represents a valuable tool for adjusting AdEx models according to a FF defined in the spiking regime and based on biological data. These models are appropriate for future research of the functional implication of bursting resonance at the theta band in large-scale granular layer network models.
| S-EPMC7381211 | biostudies-literature
Project description:Dendrite and synapse development are critical for establishing appropriate neuronal circuits, and disrupted timing of these events can alter connectivity leading to disordered neural function. In early postnatal development of cerebellar granule neurons (CGNs), the expression of many genes is temporally regulated. Further, NFI (Nuclear Factor I) proteins have been shown to play important roles in the regulation of gene expression in developing CGNs. To identify NFI-regulated genome-wide targets involved in late maturation of mouse CGNs, we performed two groups of microarray expression analysis: (1) temporal expression arrays using 1.5 and 6 day cultures of mouse CGNs representing immature and more mature CGNs, respectively, which identified 844 Temporal-Up or Down genes; and (2) NFI-regulated genes in 6 day CGN cultures that were infected at the time of plating with lentiviral vectors expressing either NFI dominant repressor (NFI-EnR) or EnR control protein. This identified 686 NFI-Up (NFI-EnR down-regulated) or NFI-Down (NFI-EnR up-regulated) genes. Overlap analysis identified 212 temporal genes that were regulated by NFI. These results indicated that NFI plays a pivotal role in the regulation of late CGN maturation.
2012-11-07 | GSE42018 | GEO
Project description:Development of the cerebellum occurs postnatally and is marked by a rapid proliferation of cerebellar granule neuron precursors (CGNPs). CGNPs are the cells of origin for SHH-driven medulloblastoma, the most common malignant brain tumor in children. Here, we investigated the role of ERK, JNK, and p38 mitogen-activated protein kinases in CGNP proliferation. We found high levels of p38? in proliferating CGNPs. Concomitantly, members of the p38 pathway, such as ASK1, MKK3 and ATF-2, were also elevated. Inhibition of the Shh pathway or CGNP proliferation blunts p38? levels, irrespective of Shh treatment. Strikingly, p38? levels were high in vivo in the external granule layer of the postnatal cerebellum, Shh-dependent mouse medulloblastomas and human medulloblastomas of the SHH subtype. Finally, knocking down p38? by short hairpin RNA-carrying lentiviruses as well as the pharmacologically inhibiting of its kinase activity caused a marked decrease in CGNP proliferation, underscoring its requirement for Shh-dependent proliferation in CGNPs. The inhibition of p38? also caused a decrease in Gli1 and N-myc transcript levels, consistent with reduced proliferation. These findings suggest p38 inhibition as a potential way to increase the efficacy of treatments available for malignancies associated with deregulated SHH signaling, such as basal cell carcinoma and medulloblastoma.
| S-EPMC3775951 | biostudies-literature
Project description:Recurrent mutations in chromatin modifiers are specifically prevalent in adolescent or adult patients with Sonic Hedgehog-associated medulloblastoma (SHH MB). Here, we report that mutations in the acetyltransferase CREBBP have opposing effects during the development of the cerebellum, the primary site of origin of SHH MB. Our data reveal that loss of Crebbp in cerebellar granule neuron progenitors (GNPs) during embryonic development of mice compromises GNP development, in part by downregulation of brain-derived neurotrophic factor (Bdnf). Interestingly, concomitant cerebellar hypoplasia was also observed in patients with Rubinstein-Taybi syndrome, a congenital disorder caused by germline mutations of CREBBP. By contrast, loss of Crebbp in GNPs during postnatal development synergizes with oncogenic activation of SHH signaling to drive MB growth, thereby explaining the enrichment of somatic CREBBP mutations in SHH MB of adult patients. Together, our data provide novel insights into time-sensitive consequences of CREBBP mutations and corresponding associations with human diseases. We used microarrays to detail the global programme of gene expression underlying the knockout of Crebbp in murine granule neuron precursors, chronically induced at embryonic stages of development.
2017-11-22 | GSE107252 | GEO