This SuperSeries is composed of the SubSeries listed below.
The Tbr2 Molecular Network Controls Cortical Neuronal Differentiation Through Complementary Genetic and Epigenetic Pathways.
Specimen part
View SamplesThe abscence of TBR2 gene in human leads to microcephaly. This condition is mimicked by the specific ablation of the murine gene in developing cerebral cortex. Herein we compared gene expression in control and Tbr2 cKO in E14.5 cerebral cortices. This approach represents a useful tool to identify the molecular mechanisms at the basis of the phenotype.
The Tbr2 Molecular Network Controls Cortical Neuronal Differentiation Through Complementary Genetic and Epigenetic Pathways.
Specimen part
View SamplesReprogramming offers the possibility to study cell fate acquisitions otherwise difficult to address in vivo. By monitoring the dynamics of gene expression during direct reprogramming of astrocytes into different neuronal subtypes via the activation of Neurog2 and Ascl1, we demonstrate that these proneural factors control largely different neurogenic programs. Among the cascades induced, however, we identified a common subset of transcription factors required for both Neurog2- and Ascl1-induced reprogramming, and combinations of these factors comprising NeuroD4 were sufficient to generate functional neurons. Notably, during astrocyte maturation REST prevents Neurog2 from binding to the NeuroD4 locus that becomes then enriched with histone H4 lysine 20 tri-methylation.
Transcriptional Mechanisms of Proneural Factors and REST in Regulating Neuronal Reprogramming of Astrocytes.
Sex, Specimen part, Treatment, Time
View SamplesSince the discovery of radial glia as the source of neurons, their heterogeneity in regard to neurogenesis has been described by clonal and time-lapse analysis in vitro. However, the molecular determinants specifying neurogenic radial glia differently from radial glia that mostly self-renew remain ill-defined. Here, we isolated two radial glial subsets that co-exist at mid-neurogenesis in the developing cerebral cortex and their immediate progeny. While one subset generates neurons directly, the other is largely non-neurogenic but also gives rise to Tbr2-positive basal precursors, thereby contributing indirectly to neurogenesis. Isolation of
Prospective isolation of functionally distinct radial glial subtypes--lineage and transcriptome analysis.
No sample metadata fields
View SamplesEvolution of the mammalian brain encompassed a remarkable increase in size of cerebral cortex, including tangential and radial expansion, but the mechanisms underlying these key parameters are still largely unknown. Here, we identified the novel DNA associated protein TRNP1 as a regulator of cerebral cortical expansion in both these dimensions. Gain and loss of function experiments in the mouse cerebral cortex in vivo demonstrate that high Trnp1 levels promote neural stem cell self-renewal and tangential expansion, while lower levels promote radial expansion resulting in a potent increase in the generation of intermediate progenitors and outer radial glial cells resulting in folding of the otherwise smooth murine cerebral cortex. Remarkably, TRNP1 expression levels exhibit regional differences also in the cerebral cortex of human fetuses anticipating radial or tangential expansion respectively. Thus, the dynamic regulation of TRNP1 is critical to regulate tangential and radial expansion of the cerebral cortex in mammals.
Prospective isolation of functionally distinct radial glial subtypes--lineage and transcriptome analysis.
Sex, Specimen part
View SamplesUnderstanding the mechanisms that specify neuronal subtypes is important to unravel the complex mechanisms of neuronal circuit assembly. Here we have identified a novel role for the transcription factor AP2 in progenitor and neuronal subtype specification in the cerebral cortex. Conditional deletion of AP2 causes misspecification of basal progenitors starting at
AP2gamma regulates basal progenitor fate in a region- and layer-specific manner in the developing cortex.
No sample metadata fields
View SamplesHow spatial chromosome organization influences genome integrity is still poorly understood. Here we show that DNA double-strand breaks (DSBs) mediated by topoisomerase 2 (TOP2) activities, are enriched at chromatin loop anchors with high transcriptional activity. Recurrent DSBs occur at CTCF/cohesin bound sites at the bases of chromatin loops and their frequency positively correlates with transcriptional output and directionality. The physiological relevance of this preferential positioning is indicated by the finding that genes recurrently translocating to drive leukemias, are highly transcribed and are enriched at loop anchors. These genes accumulate DSBs at recurrent hot spots that give rise to chromosomal fusions relying on the activity of both TOP2 isoforms and on transcriptional elongation. We propose that transcription and 3D chromosome folding jointly pose a threat to genomic stability, and are key contributors to the occurrence of genome rearrangements that drive cancer. Overall design: Nuclear RNA profiling in lymphoblastoid TK6 cell line
Spatial Chromosome Folding and Active Transcription Drive DNA Fragility and Formation of Oncogenic MLL Translocations.
Specimen part, Cell line, Subject
View SamplesWe have identified desmoglein 2 (DSG2) as the primary high-affinity receptor used by adenovirus (Ad) serotypes Ad3, Ad7, and Ad14. These serotypes represent important human pathogens causing respiratory tract infections. In epithelial cells, adenovirus binding to DSG2 triggers events reminiscent of epithelial-to-mesenchymal transition, leading to transient opening of intercellular junctions. This improves access to receptors, e.g. CD46 and Her2/neu, that are trapped in intercellular junctions. In addition to complete virions, dodecahedral particles (PtDd) formed by viral penton and fiber in excess during viral replication, can trigger DSG2-mediated opening of intercellular junctions as shown by studies with recombinant Ad3 PtDd. Our findings shed light on adenovirus biology and pathogenesis and have implications for cancer therapy.
Desmoglein 2 is a receptor for adenovirus serotypes 3, 7, 11 and 14.
Specimen part
View SamplesHeterozygous and homozygous Pax2 E11.5 embryos were collected and the intermediate mesoderm was dissected and dispersed into single cells.
Evidence for intermediate mesoderm and kidney progenitor cell specification by Pax2 and PTIP dependent mechanisms.
Specimen part
View SamplesEpstein-Barr virus (EBV) is a ubiquitous gammaherpes virus that establishes a life-long latency in over 90% of the world's population. Epstein Barr Nuclear Antigen 1, EBNA1, is the only viral protein consistently detected in all viral latency programs, as well as in all forms of EBV-associated malignancies. EBNA1 plays critical roles in the viral life cycle by fostering the replication and maintenance of the extrachromosomal viral genome as well as enhancing transcription from multiple viral promoters.
Identifying sites bound by Epstein-Barr virus nuclear antigen 1 (EBNA1) in the human genome: defining a position-weighted matrix to predict sites bound by EBNA1 in viral genomes.
No sample metadata fields
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