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SRP070835
Mus musculus
320 Downloadable Samples
NextSeq 500
Description
Certain neuron types fire spontaneously at high rates, an ability that is crucial for their function in brain circuits. The spontaneously active GABAergic neurons of the substantia nigra pars reticulata (SNr), a major output of the basal ganglia, provide tonic inhibition of downstream brain areas. A depolarizing "leak" current supports this firing pattern, but its molecular basis remains poorly understood. To understand how SNr neurons maintain tonic activity, we used single-cell RNA sequencing to determine the transcriptome of individual SNr neurons. We discovered that SNr neurons express the sodium leak current, NaLCN and that SNr neurons lacking NaLCN have impaired spontaneous firing. Overall design: RNA sequencing profiles from 87 GFP-positive GABAergic SNr neurons and 9 GFP-negative SNr cells were carried out. However only 80 samples that passed initial quality control and that were included in the data processing are represented in this record.
Publication Title
The leak channel NALCN controls tonic firing and glycolytic sensitivity of substantia nigra pars reticulata neurons.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 6 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Formation of the complex vertebrate nervous system begins when pluripotent cells of the early embryo are directed to acquire a neural fate. Although cell intrinsic controls play an important role in this process, the molecular nature of this regulation is not well defined. Here we assessed the role for Geminin, a nuclear protein expressed in embryonic cells, in neural fate acquisition from mouse embryonic stem (ES) cells. While Geminin knockdown does not affect the ability of ES cells to maintain or exit pluripotency, we found that it significantly impairs their ability to acquire a neural fate. Conversely, Geminin overexpression promotes neural gene expression, even in the presence of growth factor signaling that antagonizes neural transcriptional responses. These data demonstrate that Geminins activity contributes to mammalian neural cell fate acquisition. We investigated the mechanistic basis of this phenomenon and found that Geminin maintains a hyperacetylated and open chromatin conformation at neural genes. Interestingly, recombinant Geminin protein also rapidly alters chromatin acetylation and accessibility even when Geminin is combined with nuclear extract and chromatin in vitro. These findings define a novel activity for Geminin in regulation of chromatin structure. Together, these data support a role for Geminin as a cell intrinsic regulator of neural fate acquisition that promotes expression of neural genes by regulating chromatin accessibility and histone acetylation.
Publication Title
Geminin promotes neural fate acquisition of embryonic stem cells by maintaining chromatin in an accessible and hyperacetylated state.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus, Xenopus laevis
- 6 Downloadable Samples
- Affymetrix Xenopus laevis Genome Array (xenopuslaevis)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Geminin regulates the transcriptional and epigenetic status of neuronal fate-promoting genes during mammalian neurogenesis.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Xenopus laevis
- 6 Downloadable Samples
- Affymetrix Xenopus laevis Genome Array (xenopuslaevis)
Description
Transcriptional targets of neurogenin (Ngnr1) were identified by over-expression of an inducible form of neurogenin in Xenopus ectodermal explants. The effects of co-expressing the nucleoprotein geminin on Ngnr1-dependent target gene transactivation were defined.
Publication Title
Geminin regulates the transcriptional and epigenetic status of neuronal fate-promoting genes during mammalian neurogenesis.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 4 Downloadable Samples
- Illumina HiSeq 2000
Description
Regulating the transition from lineage-restricted progenitors to terminally differentiated cells is a central aspect of nervous system development. Here, we investigated the role of the nucleoprotein Geminin in regulating neurogenesis at a mechanistic level during both Xenopus primary neurogenesis and mammalian neuronal differentiation in vitro. The latter work utilized both neural cells derived from embryonic stem and embryonal carcinoma cells in vitro and neural stem cells from mouse forebrain. In all of these contexts, Geminin antagonized the ability of neural bHLH transcription factors to activate transcriptional programs promoting neurogenesis. Furthermore, Geminin promoted a bivalent chromatin state, characterized by the presence of both activating and repressive histone modifications, at genes encoding transcription factors that promote neurogenesis. This epigenetic state restrains the expression of genes that regulate commitment of undifferentiated stem and neuronal precursor cells to neuronal lineages. Geminin is highly expressed in undifferentiated neuronal precursor cells but is downregulated prior to differentiation. Therefore, these data support a model whereby Geminin promotes the neuronal precursor cell state by modulating both the epigenetic status and expression of genes encoding neurogenesis-promoting factors. Additional developmental signals acting in these cells can then control their transition toward terminal neuronal or glial differentiation during mammalian neurogenesis. Overall design: A mouse embryonic stem (ES) cell line for inducible knockdown of the small nucleoprotein Geminin was utilized. ES cells were used to generate neural precursor cells by monolayer culture in N2B27 media for 5 days, and doxycycline-inducible knockdown of Geminin was performed from day 3. Changes in gene expression resulting from Geminin knockdown were assessed by RNA sequencing. Three experimental replicates were generated for Geminin knockdown (plus Dox) with a corresponding no-Dox control. These were subjected to sequencing, and data were analyzed using TopHat and Cufflinks/Cuffdiff. Transcripts were considered as differentially expressed upon Gem knockdown if data met statistical significance cutoffs in Cuffdiff (sufficient sequence alignments were obtained for analysis and transcript had significant change in FPKM value (normalized transcript abundance; fragments per kb of exon per million fragments mapped) between the no Dox and plus Dox sample pairs) in at least two of the three replicates.
Publication Title
Geminin regulates the transcriptional and epigenetic status of neuronal fate-promoting genes during mammalian neurogenesis.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Histone-fold domain protein NF-Y promotes chromatin accessibility for cell type-specific master transcription factors.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Cell type-specific master transcription factors (MTFs) play vital roles in defining cell identity and function. However, the roles ubiquitous factors play in the specification of cell identity remain underappreciated. Here we show that all three subunits of the ubiquitous heterotrimeric CCAAT-binding NF-Y complex are required for the maintenance of embryonic stem cell (ESC) identity, and establish NF-Y as a novel component of the core pluripotency network. Genome-wide occupancy and transcriptomic analyses in ESCs and neurons reveal that not only does NF-Y regulate genes with housekeeping functions through cell type-invariant promoter-proximal binding, but also genes required for cell identity by binding to cell type-specific enhancers with MTFs. Mechanistically, NF-Y's distinctive DNA-binding mode promotes MTF binding at enhancers by facilitating a permissive chromatin conformation. Our studies unearth a novel function for NF-Y in promoting chromatin accessibility, and suggest that other proteins with analogous structural and DNA-binding properties may function in similar ways.
Publication Title
Histone-fold domain protein NF-Y promotes chromatin accessibility for cell type-specific master transcription factors.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 8 Downloadable Samples
- Illumina Genome Analyzer II
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Acute depletion of Tet1-dependent 5-hydroxymethylcytosine levels impairs LIF/Stat3 signaling and results in loss of embryonic stem cell identity.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 8 Downloadable Samples
Illumina Genome Analyzer II
Description
The TET family of FE(II) and 2-oxoglutarate-dependent enzymes (Tet1/2/3) promote DNA demethylation by converting 5-methylcytosine to 5-hydroxymethylcytosine (5hmC), which they further oxidize into 5-formylcytosine and 5-carboxylcytosine. Tet1 is robustly expressed in mouse embryonic stem cells (mESCs) and has been implicated in mESC maintenance. Here we demonstrate that, unlike genetic deletion, RNAi-mediated depletion of Tet1 in mESCs led to a significant reduction in 5hmC and loss of mESC identity. The differentiation phenotype due to Tet1 depletion positively correlated with the extent of 5hmC loss. Meta-analyses of genomic datasets suggested interaction between Tet1 and leukemia inhibitory factor (LIF) signaling. LIF signaling is known to promote self-renewal and pluripo-tency in mESCs partly by opposing MAPK/ERK mediated differentiation. Withdrawal of LIF leads to differentiation of mESCs. We discovered that Tet1 depletion impaired LIF-dependent Stat3-mediated gene activation by affecting Stat3's ability to bind to its target sites on chromatin. Nanog overexpression or inhibition of MAPK/ERK signaling, both known to maintain mESCs in the absence of LIF, rescued Tet1 depletion, further supporting the dependence of LIF/Stat3 signaling on Tet1. These data support the conclusion that analysis of mESCs in the hours/days immediately following efficient Tet1 depletion reveals Tet1s normal physiological role in maintaining the pluripotent state that may be subject to homeostatic compensation in genetic models.
Publication Title
Acute depletion of Tet1-dependent 5-hydroxymethylcytosine levels impairs LIF/Stat3 signaling and results in loss of embryonic stem cell identity.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Despite RNAi-based screens to uncover genes controlling embryonic stem cell (ESC) identity, the pluripotency network remains poorly characterized, as does the precise molecular mechanisms underlying the balance between self-renewal and differentiation. Here we carried out a systematic meta-analysis of published gene expression data to rank-order genes based on their likelihood of regulating ESC identity. Not only did our analysis correctly rank known pluripotency-associated genes atop the list, but it also helped unearth many novel determinants of ESC identity including several components of functionally distinct complexes, as determined using RNAi. We focus on our top-hit Nucleolin, and characterize its mechanistic role in the maintenance of ESC homeostasis by shielding from differentiation-inducing redox imbalance-induced oxidative stress. Notably, we identify a conceptually novel mechanism involving a Nucleolin-dependent bistable switch regulating the homeostatic balance between self-renewal and differentiation in ESCs. Our gene ranks represent a rich and valuable resource for uncovering novel ESC regulators.
Publication Title
Integrative framework for identification of key cell identity genes uncovers determinants of ES cell identity and homeostasis.
Sample Metadata Fields
Cell line
View Samples