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GSE47867
Rattus norvegicus
31 Downloadable Samples
Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Aging is often associated with cognitive decline, but many elderly individuals maintain a high level of function throughout life. Here we studied outbred rats, which also exhibit individual differences across a spectrum of outcomes that includes both preserved and impaired spatial memory. Previous work in this model identified the CA3 subfield of the hippocampus as a region critically affected by age and integral to differing cognitive outcomes. Earlier microarray profiling revealed distinct gene expression profiles in the CA3 region, under basal conditions, for aged rats with intact memory and those with impairment. Because prominent age-related deficits within the CA3 occur during neural encoding of new information, here we used microarray analysis to gain a broad perspective of the aged CA3 transcriptome under activated conditions. Behaviorally induced CA3 expression profiles differentiated aged rats with intact memory from those with impaired memory. In the activated profile, we observed substantial numbers of genes (greater than 1000) exhibiting increased expression in aged unimpaired rats relative to aged impaired, including many involved in synaptic plasticity and memory mechanisms. This unimpaired aged profile also overlapped significantly with a learning induced gene profile previously acquired in young adults. Alongside the increased transcripts common to both young learning and aged rats with preserved memory, many transcripts behaviorally-activated in the current study had previously been identified as repressed in the aged unimpaired phenotype in basal expression. A further distinct feature of the activated profile of aged rats with intact memory is the increased expression of an ensemble of genes involved in inhibitory synapse function, which could control the phenotype of neural hyperexcitability found in the CA3 region of aged impaired rats. These data support the conclusion that aged subjects with preserved memory recruit adaptive mechanisms to retain tight control over excitability under both basal and activated conditions.
Publication Title
Behaviorally activated mRNA expression profiles produce signatures of learning and enhanced inhibition in aged rats with preserved memory.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Low levels of the cell cycle regulator p27Kip1 are associated with a worse outcome in many tumor types. We report here a new regulatory role of p27Kip1 as a transcriptional regulator. In association with transcriptional factors such as ETS and E2F4 and co-repressors like p130, HDACs and mSin3A, p27 binds to promoters of multiple genes leading to their repression. The p27-target genes participate in RNA processing, translation, respiration and cell cycle. Remarkably, p27-target genes are over-expressed in different human tumors in tight association with a poor clinical prognosis. We also observed a clear correlation between low levels of p27 and over-expression of p27-target genes in tumors. Overall, our findings indicate new tumor suppressor roles of p271 as a transcriptional regulator of genes relevant for oncogenesis.
Publication Title
p27Kip1 represses transcription by direct interaction with p130/E2F4 at the promoters of target genes.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 40 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Rapid encoding of new information alters the profile of plasticity-related mRNA transcripts in the hippocampal CA3 region.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 3 Downloadable Samples
- Illumina human-6 v2.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Patterns of histone H3 lysine 27 monomethylation and erythroid cell type-specific gene expression.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Rattus norvegicus
- 14 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
A theoretical framework for the function of the medial temporal lobe system in memory defines differential contributions of the hippocampal subregions with regard to pattern recognition retrieval processes and encoding of new information. To investigate molecular programs of relevance, we designed a spatial learning protocol to engage a pattern separation function to encode new information. After background training, two groups of animals experienced the same new training in a novel environment, however only one group was provided spatial information and demonstrated spatial memory in a retention test. Global transcriptional analysis of the microdissected subregions of the hippocampus exposed a CA3 pattern that was sufficient to clearly segregate spatial learning animals from control. Individual gene and functional group analysis anchored these results to previous work in neural plasticity. From a multitude of expression changes, increases in camk2a, rasgrp1 and nlgn1 were confirmed by in situ hybridization. Furthermore, siRNA inhibition of nlgn1 within the CA3 subregion impaired spatial memory performance, pointing to mechanisms of synaptic remodeling as a basis for rapid encoding of new information in long-term memory.
Publication Title
Rapid encoding of new information alters the profile of plasticity-related mRNA transcripts in the hippocampal CA3 region.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 14 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
A theoretical framework for the function of the medial temporal lobe system in memory defines differential contributions of the hippocampal subregions with regard to pattern recognition retrieval processes and encoding of new information. To investigate molecular programs of relevance, we designed a spatial learning protocol to engage a pattern separation function to encode new information. After background training, two groups of animals experienced the same new training in a novel environment, however only one group was provided spatial information and demonstrated spatial memory in a retention test. Global transcriptional analysis of the microdissected subregions of the hippocampus exposed a CA3 pattern that was sufficient to clearly segregate spatial learning animals from control. Individual gene and functional group analysis anchored these results to previous work in neural plasticity. From a multitude of expression changes, increases in camk2a, rasgrp1 and nlgn1 were confirmed by in situ hybridization. Furthermore, siRNA inhibition of nlgn1 within the CA3 subregion impaired spatial memory performance, pointing to mechanisms of synaptic remodeling as a basis for rapid encoding of new information in long-term memory.
Publication Title
Rapid encoding of new information alters the profile of plasticity-related mRNA transcripts in the hippocampal CA3 region.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 12 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
A theoretical framework for the function of the medial temporal lobe system in memory defines differential contributions of the hippocampal subregions with regard to pattern recognition retrieval processes and encoding of new information. To investigate molecular programs of relevance, we designed a spatial learning protocol to engage a pattern separation function to encode new information. After background training, two groups of animals experienced the same new training in a novel environment, however only one group was provided spatial information and demonstrated spatial memory in a retention test. Global transcriptional analysis of the microdissected subregions of the hippocampus exposed a CA3 pattern that was sufficient to clearly segregate spatial learning animals from control. Individual gene and functional group analysis anchored these results to previous work in neural plasticity. From a multitude of expression changes, increases in camk2a, rasgrp1 and nlgn1 were confirmed by in situ hybridization. Furthermore, siRNA inhibition of nlgn1 within the CA3 subregion impaired spatial memory performance, pointing to mechanisms of synaptic remodeling as a basis for rapid encoding of new information in long-term memory.
Publication Title
Rapid encoding of new information alters the profile of plasticity-related mRNA transcripts in the hippocampal CA3 region.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 3 Downloadable Samples
- Illumina human-6 v2.0 expression beadchip
Description
ERYTHROID CELL-TYPE SPECIFIC GENE EXPRESSION
Publication Title
Patterns of histone H3 lysine 27 monomethylation and erythroid cell type-specific gene expression.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 6 Downloadable Samples
IlluminaHiSeq2000
Description
CTCF and cohesinSA-1 are regulatory proteins involved in a number of critical cellular processes including transcription, maintenance of chromatin domain architecture, and insulator function. To assess changes in the CTCF and cohesinSA-1 interactomes during erythropoiesis, chromatin immunoprecipitation coupled with high throughput sequencing and mRNA transcriptome analyses via RNA-seq were performed in primary human HSPC hematopoietic stem and progenitor cells (HSPC) and primary human erythroid cells from single donors. Sites of CTCF and cohesinSA-1 co-occupancy were enriched in gene promoters in HSPC and erythroid cells compared to single CTCF or cohesin sites. Cell type-specific CTCF sites in erythroid cells were linked to highly expressed genes, with the opposite pattern observed in HSPCs. Chromatin domains were identified by ChIP-seq with antibodies against trimethylated lysine 27 histone 3, a modification associated with repressive chromatin. Repressive chromatin domains increased in both number and size during hematopoiesis, with many more repressive domains in erythroid cells than HSPCs. CTCF and cohesinSA-1 marked the boundaries of these repressive chromatin domains in a cell-type specific manner. These genomic data support the hypothesis that CTCF and cohesinSA-1 have multiple roles in the regulation of gene expression during erythropoiesis including transcriptional regulation at gene promoters and maintenance of chromatin architecture. Overall design: CD34+-selected stem and progenitor cells were expanded for three days in the absence of EPO. The cells were further cultured in the presence of EPO, and cells differentiated into R3/R4 nucleated erythroid cells. RNA was isolated from three biological replicates of each cell type and sequencing libraries were prepared from poly A selected RNA.
Publication Title
CTCF and CohesinSA-1 Mark Active Promoters and Boundaries of Repressive Chromatin Domains in Primary Human Erythroid Cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In the past three years the role of inflammatory cytokines and chemokines in tumour promotion and progression has been intensively studied. The chemokine receptor CXCR4 and its ligand CXCL12 are commonly expressed in malignant cells from primary tumours, metastases and also in malignant cell lines. To investigate the biological significance of this receptor/ligand pair, we knocked-down CXCR4 expression in ovarian cancer cell line IGROV-1 using shRNA, and established stable cell lines.
Publication Title
A dynamic inflammatory cytokine network in the human ovarian cancer microenvironment.
Sample Metadata Fields
No sample metadata fields
View Samples