Rattus norvegicus
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ABSTRACT:
PROVIDER: PRJNA128131 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Transcription of immediate early genes (IEGs) in neurons is exquisitely sensitive to neuronal activity, but the mechanism underlying the earliest of these transcription events is largely unknown. Here we demonstrate that very fast IEGs (VF-IEGs) such as arc/arg3.1 are poised for rapid transcription by the stalling of RNA Polymerase II (Pol II) just downstream of the transcription start site. RNAi-depletion of two subunits of Negative Elongation Factor, a mediator of Pol II stalling, reduces the Pol II occupancy of the arc promoter and compromises the rapid induction of arc and other VF-IEGs. In contrast, reduction of Pol II stalling did not prevent expression of fast IEGs (F-IEGs). These F-IEGs are expressed with comparatively slower kinetics and largely lack promoter proximal Pol II stalling. Taken together, our data strongly indicate that very fast kinetics of neuronal IEG expression require poised Pol II and suggest a role for this mechanism in transcription-dependent learning and memory. Examination of Pol II bindnig genome-wide in rat neurons
2011-05-24 | E-GEOD-22878 | biostudies-arrayexpress
Project description:Transcription of immediate early genes (IEGs) in neurons is exquisitely sensitive to neuronal activity, but the mechanism underlying the earliest of these transcription events is largely unknown. Here we demonstrate that very fast IEGs (VF-IEGs) such as arc/arg3.1 are poised for rapid transcription by the stalling of RNA Polymerase II (Pol II) just downstream of the transcription start site. RNAi-depletion of two subunits of a mediator of Pol II stalling, Negative Elongation Factor, reduces Pol II occupancy of the arc promoter and compromises rapid induction of arc and other VF-IEGs. In contrast, reduction of Pol II stalling did not prevent expression of other fast IEGs (F-IEGs). These F-IEGs are expressed with comparatively slower kinetics and largely lack promoter proximal Pol II stalling. Taken together, our data strongly indicate that very fast kinetics of neuronal IEG expression require poised Pol II and suggest a role for this mechanism in transcription-dependent learning and memory. TTX withdrawal induced neuronal activity. To study activity-induced gene expression, neurons were treated with TTX for 48 hours and then TTX was washed out either for 15 minutes (W15) or for 45 minutes (W45). Gene expression was measured in these two groups in comparison to TTX treated neurons.
2011-04-14 | E-GEOD-22622 | biostudies-arrayexpress
Project description:Transcription of immediate early genes (IEGs) in neurons is exquisitely sensitive to neuronal activity, but the mechanism underlying the earliest of these transcription events is largely unknown. Here we demonstrate that very fast IEGs (VF-IEGs) such as arc/arg3.1 are poised for rapid transcription by the stalling of RNA Polymerase II (Pol II) just downstream of the transcription start site. RNAi-depletion of two subunits of a mediator of Pol II stalling, Negative Elongation Factor, reduces Pol II occupancy of the arc promoter and compromises rapid induction of arc and other VF-IEGs. In contrast, reduction of Pol II stalling did not prevent expression of other fast IEGs (F-IEGs). These F-IEGs are expressed with comparatively slower kinetics and largely lack promoter proximal Pol II stalling. Taken together, our data strongly indicate that very fast kinetics of neuronal IEG expression require poised Pol II and suggest a role for this mechanism in transcription-dependent learning and memory.
2011-04-15 | GSE22622 | GEO
Project description:Transcription of immediate early genes (IEGs) in neurons is exquisitely sensitive to neuronal activity, but the mechanism underlying the earliest of these transcription events is largely unknown. Here we demonstrate that very fast IEGs (VF-IEGs) such as arc/arg3.1 are poised for rapid transcription by the stalling of RNA Polymerase II (Pol II) just downstream of the transcription start site. RNAi-depletion of two subunits of Negative Elongation Factor, a mediator of Pol II stalling, reduces the Pol II occupancy of the arc promoter and compromises the rapid induction of arc and other VF-IEGs. In contrast, reduction of Pol II stalling did not prevent expression of fast IEGs (F-IEGs). These F-IEGs are expressed with comparatively slower kinetics and largely lack promoter proximal Pol II stalling. Taken together, our data strongly indicate that very fast kinetics of neuronal IEG expression require poised Pol II and suggest a role for this mechanism in transcription-dependent learning and memory.
2011-05-24 | GSE22878 | GEO
Project description:The immediate early gene product activity-regulated cytoskeleton-associate protein (Arc or Arg3.1) is a major regulator long-term synaptic plasticity with critical roles in postnatal cortical development and memory formation. However, the molecular basis of Arc function is not defined. Arc is a hub protein with interaction partners in the postsynaptic neuronal compartment and nucleus. In vitro biochemical and biophysical analysis of purified recombinant Arc show formation of low-order oligomers and larger particles including retrovirus-like capsids. Here, we provide evidence for naturally occurring Arc oligomers in mammalian brain. Using in situ protein crosslinking to trap weak Arc-Arc interactions, we identified in various preparations a prominent Arc immunoreactive band on SDS-PAGE of molecular mass corresponding to a dimer. While heavier Arc species or putative trimers and tetramers were detected, they were of lower abundance. In the dentate gyrus (DG) of adult anesthetized rats, induction of long-term potentiation (LTP) by high-frequency stimulation (HFS) of medial perforant synapses or by brief intrahippocampal infusion of BDNF led to a massive increase in Arc dimer expression. Arc immunoprecipitation of crosslinked DG tissue showed enhanced expression of dimer during four hours of LTP maintenance. Mass spectrometric proteomic analysis of immunoprecipitated, gel-excised bands corroborated detection of Arc dimer. Furthermore, Arc dimer was constitutively expressed in naïve cortical, hippocampal and DG tissue, with lowest levels in the DG. Taken together the results implicate Arc dimers as the predominant low-oligomeric form in mammalian brain, exhibiting regional differences in its constitutive expression and pronounced enhanced expression during DG LTP.
2023-07-20 | PXD039612 | Pride
Project description:Variant histone H2A.Z is an essential and conserved regulator of eukaryotic gene transcription. However, the exact role of this histone in the process remains perplexing. In vertebrates, H2A.Z has two hypervariants – H2A.Z.1 and H2A.Z.2 – that have almost identical amino-acid sequences excepting three residues. Due to such similarity, functional specificity of these hypervariants in neurobiological processes, if any, remain largely unknown. In this study with dissociated mature cortical neurons, we asked if H2A.Z hypervariants have functional specificity in regulating basal and activity-induced gene transcription. Hypervariant-specific RNAi and microarray analyses revealed that H2A.Z.1 and H2A.Z.2 regulate basal expression of largely non-overlapping gene-sets, including genes that code for several synaptic proteins. In response to neuronal activity, depletion of H2A.Z hypervariants impairs transcription of our model gene Arc differentially. As part of the +1 nucleosome, H2A.Z.2, not H2A.Z.1, is necessary for rapid immediate-early transcription by facilitating RNA Pol II promoter proximal pausing. In contrast, H2A.Z.1 plays complicated and perhaps indirect roles that affect Arc transcription kinetics context-dependently. Context-dependent roles of H2A.Z hypervariants are also evident amongst several other immediate early genes where their regulatory roles vary from gene to gene under different conditions. Together, our data suggest that H2A.Z hypervariants have context-specific roles that complement each other to mediate activity-induced neuronal gene transcription.
2017-09-14 | GSE96886 | GEO
Project description:Mice deficient in the glucocorticoid-regenerating enzyme 11β-HSD1 resist age-related spatial memory impairment. To investigate the mechanisms/pathways involved, we used microarrays to identify differentially expressed hippocampal genes that associate with cognitive ageing and 11β-HSD1. Aged wild-type mice were separated into memory-impaired and unimpaired relative to young controls according to their performance in the Y-maze. All individual aged 11β-HSD1-deficient mice showed intact spatial memory. The majority of differentially expressed hippocampal genes were increased with ageing (e.g. immune/inflammatory response genes) with no genotype differences. However, the neuronal-specific transcription factor, Npas4 and immediate early gene, Arc were reduced (relative to young) in the hippocampus of memory-impaired but not unimpaired aged wild-type or aged 11β-HSD1-deficient mice. Quantitative RT-PCR and in situ hybridization confirmed reduced Npas4 and Arc mRNA expression in memory-impaired aged wild-type mice. These findings suggest that 11β-HSD1 may contribute to the decline in Npas4 and Arc mRNA levels associated with memory impairment during ageing, and that decreased activity of synaptic plasticity pathways involving Npas4 and Arc may, in part, underlie the memory deficits seen in cognitively-impaired aged wild-type mice. 20 samples, 5 groups of 4 biological replicates each. Young, Wild Type animals are overall controls
2015-11-23 | E-GEOD-68515 | biostudies-arrayexpress
Project description:Arc is an activity regulated neuronal protein yet little is known about its protein interactions, assembly into multiprotein complexes, role in human disease and cognition. We applied an integrated proteomic and genetic strategy using targeted tagging of a Tandem Affinity Purification (TAP) tag and Venus fluorescent protein into the endogenous Arc gene in mice, biochemical and proteomic characterization of native complexes in wild type and knockout mice, and human genetic analyses of disease and intelligence. TAP tagging enabled efficient purification of complexes and identification of many novel Arcinteracting proteins, of which PSD95 was the most abundant. PSD95 was essential for Arc assembly into 1.5 MDa complexes and activity-dependent recruitment to excitatory synapses. Integrating human genetic data with proteomic data showed postsynaptic Arc- PSD95 complexes are enriched in schizophrenia, intellectual disability, autism and epilepsy mutations and normal variants in intelligence. Arc-PSD95 postsynaptic complexes are a molecular substrate for the convergence of normal and pathological genetic variants impacting on human cognitive function.
2017-10-19 | PXD007283 | Pride
Project description:Neuronal activity causes the rapid expression of immediate early genes that are crucial for experience driven changes to synapses, learning, and memory. Here, using both molecular and genome-wide next generation sequencing methods, we report that neuronal activity stimulation triggers the formation of DNA double strand breaks (DSBs) in the promoters of a subset of early-response genes, including Fos, Npas4, and Egr1. Generation of targeted DNA DSBs within Fos and Npas4 promoters is sufficient to induce their expression even in the absence of an external stimulus. Activity-dependent DSB formation is likely mediated by the type II topoisomerase, Topoisomerase IIb (Topo IIb), and knockdown of Topo IIb attenuates both DSB formation and early response gene expression following neuronal stimulation. Our results suggest that DSB formation is a physiological event that rapidly resolves topological constraints to early-response gene expression in neurons. Generation of sequencing data from ChIP-seq with antibodies against γH2AX and Topo IIβ after neuronal activity stimulation, and RNA-seq after etoposide treatment
2015-06-04 | E-GEOD-61887 | biostudies-arrayexpress