Altered gene expression is associated with age-dependent memory impairment
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE20270 | GEO | 2010/04/19
SECONDARY ACCESSION(S): PRJNA124135
REPOSITORIES: GEO
Similar Datasets
Project description:The mechanisms underlying age-associated memory impairment are not well understood. We have shown that the onset of memory disturbances in the aging brain is associated with altered hippocampal chromatin plasticity. During learning, aged mice display a specific deregulation of histone H4 lysine 12 (H4K12) acetylation. To analyze if deregulated H4K12 acetylation impacts on learning-induced gene-expression required for memory consolidation we performed a high-density oligonucleotide microarray to compare the entire hippocampal gene-expression profile of 3 and 16-month-old mice during memory consolidation. In order to identify genes differentially regulated between 3- and 16-month old mice upon fear conditioning we subjected 3- and 16-month old mice to fear conditioning (4 mice each group, total 8 mice) . Mice of the same age that were handled but not subjected to any of the employed behavior paradigms served as control (4 mice 3-month old and 4 mice 16-month old, total 8 mice). During fear conditioning mice are subjected to a novel context followed by a mild electric foot-shock (context-shock exposure). In order to identify genes that are differentially regulated upon fear conditioning and are specific to associative learning we also tested the hippocampal gene-expression profile of 3-month old mice subjected to the same context-exposure that is not followed by a foot-shock (Context-exposure) (4 mice) or receive an immediate foot shock once they are placed in the context and only afterwards are allowed to explore the context (shock-context exposure) (4 mice). In order to identify genes that are regulated upon fear conditioning and are specific to associative learning we compared the hippocampal gene-expression profile of mice subjected to fear conditioning (context-shock), context or shock-context exposure regarding to their age-matched control mice (3 month old) mentioned above (control). Hippocampi from each mice were tested resulting to 24 samples which were separately hybridized (OneColor Array Design).
2010-04-28 | E-GEOD-20270 | biostudies-arrayexpress
Project description:Post-learning sleep plays an important role in hippocampal memory processing, including contextual fear memory (CFM) consolidation. Here, we used targeted recombination in activated populations (TRAP) to label context-encoding engram neurons in the hippocampal dentate gyrus (DG) and assessed reactivation of these neurons during post-learning sleep. We find that post-learning sleep deprivation (SD), which impairs CFM consolidation, selectively disrupts reactivation in inferior blade DG engram neurons. This change was linked to more general suppression of neuronal activity markers in the inferior, but not superior, DG blade by SD. To further characterize how learning and subsequent sleep or SD affect these (and other) hippocampal subregions, we used subregion-specific spatial profiling of transcripts and proteins. We found that transcriptomic responses to sleep loss differed greatly between hippocampal regions CA1, CA3, and DG inferior blade, superior blade, and hilus. Critically, learning-driven transcriptomic changes, measured 6 h following contextual fear learning, were limited to the two DG blades, differed dramatically between the blades, and were absent from all other regions. Similarly, protein abundance in these hippocampal subregions were differentially impacted by sleep vs. SD and by prior learning, with the majority of alterations to protein expression restricted to DG. Together, these data suggest that the DG plays an essential role in the consolidation of hippocampal memories, and that the effects of sleep and sleep loss on the brain are highly subregion-specific, even within the DG itself.
2024-03-01 | GSE229080 | GEO
Project description:Post-learning sleep plays an important role in hippocampal memory processing, including contextual fear memory (CFM) consolidation. Here, we used targeted recombination in activated populations (TRAP) to label context-encoding engram neurons in the hippocampal dentate gyrus (DG) and assessed reactivation of these neurons during post-learning sleep. We find that post-learning sleep deprivation (SD), which impairs CFM consolidation, selectively disrupts reactivation in inferior blade DG engram neurons. This change was linked to more general suppression of neuronal activity markers in the inferior, but not superior, DG blade by SD. To further characterize how learning and subsequent sleep or SD affect these (and other) hippocampal subregions, we used subregion-specific spatial profiling of transcripts and proteins. We found that transcriptomic responses to sleep loss differed greatly between hippocampal regions CA1, CA3, and DG inferior blade, superior blade, and hilus. Critically, learning-driven transcriptomic changes, measured 6 h following contextual fear learning, were limited to the two DG blades, differed dramatically between the blades, and were absent from all other regions. Similarly, protein abundance in these hippocampal subregions were differentially impacted by sleep vs. SD and by prior learning, with the majority of alterations to protein expression restricted to DG. Together, these data suggest that the DG plays an essential role in the consolidation of hippocampal memories, and that the effects of sleep and sleep loss on the brain are highly subregion-specific, even within the DG itself.
2024-03-01 | GSE229081 | GEO
Project description:Histone acetylation has been implicated in learning and memory in the brain, however, its function at the level of the genome and at individual genetic loci remains poorly investigated. This study examines a key acetylation mark, histone H4 lysine 5 acetylation (H4K5ac), genome-wide and its role in activity-dependent gene transcription in the adult mouse hippocampus following contextual fear conditioning. Using ChIP-Seq, we identified 23,235 genes in which H4K5ac correlates with absolute gene expression in the hippocampus. However, in the absence of transcription factor binding sites 150 bp upstream of the transcription start site, genes were associated with higher H4K5ac and expression levels. We further establish H4K5ac as a ubiquitous modification across the genome. Approximately one-third of all genes have above average H4K5ac, of which ~15% are specific to memory formation and ~65% are co-acetylated for H4K12. Although H4K5ac is prevalent across the genome, enrichment of H4K5ac at specific regions in the promoter and coding region are associated with different levels of gene expression. Additionally, unbiased peak calling for genes differentially acetylated for H4K5ac identified 114 unique genes specific to fear memory, over half of which have not previously been associated with memory processes. Our data provide novel insights into potential mechanisms of gene priming and bookmarking by histone acetylation following hippocampal memory activation. Specifically, we propose that hyperacetylation of H4K5 may prime genes for rapid expression following activity. More broadly, this study strengthens the importance of histone posttranslational modifications for the differential regulation of transcriptional programs in cognitive processes.
2013-08-18 | GSE30325 | GEO
Project description:FTY720/Fingolimod, an FDA-approved drug for treatment of multiple sclerosis, has beneficial effects in the CNS that are not yet well understood, independent of its effects on immune cell trafficking. Here we show that FTY720 enters the nucleus where it is phosphorylated by sphingosine kinase 2 (SphK2) and nuclear FTY720-P that accumulates there, binds and inhibits class I histone deacetylases (HDACs) enhancing specific histone acetylations. FTY720 is also phosphorylated in mice and accumulates in various brain regions, including hippocampus, inhibits HDACs and enhances histone acetylation and gene expression programs associated with memory and learning leading to improvement of memory impairment independently of its immunosuppressive actions. Our data suggest that sphingosine-1-phosphate and SphK2 play specific roles in memory functions and that FTY720 may be a useful adjuvant therapy to facilitate extinction of aversive memories. Microarrays were used to survey the effect of FTY720 treatment during contextual fear conditioning on hippocampal gene expression. Total RNA was isolated from individual hippocampi of SCID mice 1 hour following fear consolidation testing after the third day of FTY720 or saline treatment. Eight arrays were run in total: 4 FTY720-treated mice and 4 saline-treated control mice.
2014-05-12 | E-GEOD-57015 | biostudies-arrayexpress
Project description:Aerobic exercise is well known to promote neuroplasticity and hippocampal memory. In the developing brain, early-life exercise (ELE) can lead to lasting improvements in hippocampal function, yet molecular mechanisms underlying this phenomenon have not been fully explored. In this study, adolescent transgenic mice harboring the “NuTRAP” (Nuclear tagging and Translating Ribosome Affinity Purification) cassette in Emx1 expressing neurons (“Emx1-NuTRAP” mice) undergo ELE followed by a hippocampal learning task, in order to determine the molecular underpinnings of exercise contributing to improved hippocampal memory performance. We simultaneously isolate and sequence translating mRNA and nuclear chromatin from a single hippocampus in a cell-type specific manner (excitatory neurons), demonstrate validity of our new technical approach, and couple multi-omics sequencing data to evaluate histone modifications H4K8ac and H3K27me3 and their influence on gene expression after ELE. We then evaluate new gene expression – histone modification relationships specifically during hippocampal memory consolidation that may play a critical role in facilitated memory after ELE. Our data reveal novel candidate gene-histone modification interactions and implicate gene regulatory pathways involved in ELE’s impact on hippocampal learning and memory.
2022-10-18 | GSE208633 | GEO
Project description:Aerobic exercise is well known to promote neuroplasticity and hippocampal memory. In the developing brain, early-life exercise (ELE) can lead to lasting improvements in hippocampal function, yet molecular mechanisms underlying this phenomenon have not been fully explored. In this study, adolescent transgenic mice harboring the “NuTRAP” (Nuclear tagging and Translating Ribosome Affinity Purification) cassette in Emx1 expressing neurons (“Emx1-NuTRAP” mice) undergo ELE followed by a hippocampal learning task, in order to determine the molecular underpinnings of exercise contributing to improved hippocampal memory performance. We simultaneously isolate and sequence translating mRNA and nuclear chromatin from a single hippocampus in a cell-type specific manner (excitatory neurons), demonstrate validity of our new technical approach, and couple multi-omics sequencing data to evaluate histone modifications H4K8ac and H3K27me3 and their influence on gene expression after ELE. We then evaluate new gene expression – histone modification relationships specifically during hippocampal memory consolidation that may play a critical role in facilitated memory after ELE. Our data reveal novel candidate gene-histone modification interactions and implicate gene regulatory pathways involved in ELE’s impact on hippocampal learning and memory.
2022-10-18 | GSE208714 | GEO
Project description:Histone acetylation is a key component in the consolidation of long-term fear memories, which are models for highly resilient and durable memory. Histone acetylation is fueled by acetyl-CoA and recently, nuclear-localized metabolic enzymes that produce this metabolite have emerged as direct and local regulators of histone acetylation. In particular, Acetyl-coA synthetase 2 (ACSS2) mediates histone acetylation in the mouse hippocampus. However, whether ACSS2 regulates long-term fear memory remains to be determined. Here, we show that Acss2 knockout is well-tolerated in mice, yet the Acss2 null mouse exhibits reduced acquisition of long-term fear memory. Loss of Acss2 leads to reductions in both histone acetylation and expression of critical learning and memory-related genes in the dorsal hippocampus, specifically following fear conditioning. Further, systemic administration of blood-brain-barrier (BBB)-permeable Acss2 inhibitors during the consolidation window reduces fear memory formation in mice and rats, and reduces anxiety in a predator-scent-stress (PSS) paradigm. Our findings suggest that nuclear acetyl-CoA metabolism via ACSS2 plays a critical, previously unappreciated role in the formation of fear memories.
2022-07-19 | GSE199887 | GEO
Project description:Sleep has been strongly implicated in learning and especially in the reprocessing of recently acquired memory. Children with intellectual disability (ID) tend to have sleep-wake disturbances, which may contribute to the pathophysiology of the disease. As far as sleep is, in part, a circadian process, we decided to study rhythmic gene expression in hippocampus, a brain structure, which plays a key role in memory in human and rodents. By investigating the transcriptome of mouse adult hippocampus, we report here the identification of 663 circadian rhythm (CR)-regulated genes, which have been clustered in four categories, based on their temporal pattern of expression. In addition to the standard core-clock genes, enrichment analysis of the hippocampal CR-regulated genes revealed the presence of several transcription factors, underlying the existence of an inter-regulation of genes' expression between clusters. Interestingly, these hippocampal circadian rhythm-regulated genes are very enriched in sleep/wakefulness related genes. We show here that glucocorticoid signaling, already shown to be involved in memory regulation, is a circadian regulated pathway in hippocampus. Furthermore, we identified a list of 30 CR-regulated ID genes. Our results demonstrate that hippocampus can be considered as a peripheral oscillator and illustrate the link between circadian rhythm, sleep, intellectual disability and memory consolidation.
2016-03-12 | GSE66875 | GEO
Project description:Sleep has been strongly implicated in learning and especially in the reprocessing of recently acquired memory. Children with intellectual disability (ID) tend to have sleep-wake disturbances, which may contribute to the pathophysiology of the disease. As far as sleep is, in part, a circadian process, we decided to study rhythmic gene expression in hippocampus, a brain structure, which plays a key role in memory in human and rodents. By investigating the transcriptome of mouse adult hippocampus, we report here the identification of 663 circadian rhythm (CR)-regulated genes, which have been clustered in four categories, based on their temporal pattern of expression. In addition to the standard core-clock genes, enrichment analysis of the hippocampal CR-regulated genes revealed the presence of several transcription factors, underlying the existence of an inter-regulation of genes' expression between clusters. Interestingly, these hippocampal circadian rhythm-regulated genes are very enriched in sleep/wakefulness related genes. We show here that glucocorticoid signaling, already shown to be involved in memory regulation, is a circadian regulated pathway in hippocampus. Furthermore, we identified a list of 30 CR-regulated ID genes. Our results demonstrate that hippocampus can be considered as a peripheral oscillator and illustrate the link between circadian rhythm, sleep, intellectual disability and memory consolidation. In order to identify circadian rhythm-regulated genes in mouse hippocampus, we realized a study in dark-dark conditions, thus allowing to overcome the effects induced by light changes. To systematically identify genes with circadian regulated expression, RNA samples from the hippocampus of three mice at four Circadian Time (CT) points were used for expression profiling using Agilent microarray technology. The dark/dark period started at 7 p.m. The Circadian Time (CT) 18 samples were taken after 30 h of continuous dark; the other circadian times followed at 6-h intervals: CT0, CT6 and CT12 after 36, 42 and 48 h of continuous darkness, respectively.
2016-03-12 | E-GEOD-66875 | biostudies-arrayexpress