Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA131611 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The acetylation levels of histones and other proteins change during aging and have been linked to neurodegeneration. Here we show that deletion of the histone acetyltransferase (HAT) co-factor Trrap specifically impairs the function of the transcription factor Sp1, reduces its stability and causes a decrease in histone acetylation at Sp1 target genes. Modulation of Sp1 function by Trrap acts as a hub regulating multiple processes involved in neuron and neural stem cells function and maintenance including microtubule dynamics and the Wnt signaling pathway. Consistently, Trrap conditional mutants exhibit all hallmarks of neurodegeneration including dendrite retraction and axonal swellings, neuron death, astrogliosis, microglia activation, demyelination and decreased adult neurogenesis. Our results uncovered a novel functional network, essential to prevent neurodegeneration, and involving the specific regulation of Sp1 transcription factor and its downstream targets by Trrap-HAT.
2021-02-17 | GSE131283 | GEO
Project description:Systemic inflammatory reactions mediated by chronic infections activate microglia in the central nervous system (CNS) and have been postulated to exacerbate neurodegenerative diseases. We now demonstrate in vivo that repeated systemic challenge of mice with bacterial lipopolysaccharides (LPS) maintains an elevated microglial inflammatory response and triggers neurodegeneration. Repeated chronic intraperitoneal application of LPS over four consecutive days induced loss of dopaminergic neurons in the substantia nigra, a process that was accompanied by decreased levels of dopamine in the striatum. In contrast, total cumulative LPS dose given intraperitoneally within a single acute application did not induce a decrease in dopamine levels nor neurodegeneration. Mice that received repeated systemic LPS application showed increased microglial activation, elevated production of proinflammatory cytokines and activation of the classical complement and its associated phagosome pathway in the brain. Loss of dopaminergic neurons induced by repeated systemic LPS application was rescued in complement C3 deficient mice, confirming an involvement of the complement system in neurodegeneration. Thus, our data demonstrate that repeated systemic exposure to bacterial LPS induces a microglial phagosomal inflammatory response, leading to complement-dependent damage of dopaminergic neurons.
2014-07-11 | E-MTAB-1770 | biostudies-arrayexpress
Project description:Defining the microglia response during the time course of chronic neurodegeneration
| PRJNA292794 | ENA
Project description:Engrams are considered to be substrates for memory storage, and the functional dysregulation of the engrams leads to cognition impairment.However, the cellular basis for these maladaptive changes lead to the forgetting of memories remains unclear. Here we found that the expression of autophagy protein 7 (Atg7) mRNA was dramatically upregulated in aged DG engrams, and led to the forgetting of contextual fear memory and the activation of surrounding microglia.To determine mechanism by which autophagy in DG engrams activates the surrounding microglia, mice were co-injected AAV-RAM-Cre either with AAV-Dio-Atg7-Flag or AAV-Dio- EYFP in dorsal dentate gyrus to overexpress ATG7 in the DG memory engrams. Microglia were separated using magnetic-activated cell sorting and subjected to RNA-Seq in dorsal hippocampus .Bioinformatics analysis shown overexpression of Atg7 in dorsal DG memory engrams caused an increase in the expression of Tlr2 in the surrounding microglia.Depletion of Toll-like receptor 2/4 (TLR2/4) in DG microglia prohibited excessive microglial activation and synapse elimination induced by the overexpression of ATG7 in DG engrams, and thus prevented forgetting. Furthermore, the expression of Rac1, a Rho-GTPases which regulates active forgetting in both fly and mice, was upregulated in aged engrams. Optogentic activation of Rac1 in DG engrams promoted the autophagy of the engrams, the activation of microglia, and the forgetting of fear memory. Invention of the Atg7 expression and microglia activation attenuated forgetting induced by activation of Rac1 in DG engrams. Together, our findings revealed autophagy-dependent synapse elimination of DG engrams by microglia as a novel forgetting mechanism.
2021-08-24 | GSE169019 | GEO
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
| S-EPMC8784167 | biostudies-literature
Project description:Transcriptional Profile of Microglia in Neurodegeneration
| PRJNA358018 | ENA
Project description:Aging is the predominant risk factor for neurodegenerative diseases. One key phenotype as brain ages is the aberrant innate immune response characterized by proinflammation. However, the molecular mechanisms underlying aging-associated proinflammation are poorly defined. Whether chronic inflammation plays a causal role in cognitive decline in aging and neurodegeneration has not been established. Here we established a mechanistic link between chronic inflammation and aging microglia, and demonstrated a causal role of aging microglia in neurodegenerative cognitive deficits. Expression of microglial SIRT1 reduces with the aging of microglia. Genetic reduction of microglial SIRT1 elevates IL-1β selectively, and exacerbates cognitive deficits in aging and in transgenic mouse models of frontotemporal dementia (FTD). Interestingly, the selective activation of IL-1β transcription by SIRT1 deficiency is likely mediated through hypomethylating the proximal promoter of IL-1β. Consistent with our findings in mice, selective hypomethylation of IL-1β at two CpG sites are found in normal aging humans and demented patients with tauopathy. Our findings reveal a novel epigenetic mechanism in aging microglia that contributes to cognitive deficits in neurodegenerative diseases. Study of changes related to alterations of SIRT1 levels in microglia of young and aged animals and in models of neurodegenerative dementia
2014-10-01 | E-GEOD-56452 | biostudies-arrayexpress
Project description:The acetylation levels of histones and other proteins change during aging and have been linked to neurodegeneration. Here we show that deletion of the histone acetyltransferase (HAT) co-factor Trrap specifically impairs the function of the transcription factor Sp1, reduces its stability and causes a decrease in histone acetylation at Sp1 target genes. Modulation of Sp1 function by Trrap acts as a hub regulating multiple processes involved in neuron and neural stem cells function and maintenance including microtubule dynamics and the Wnt signaling pathway. Consistently, Trrap conditional mutants exhibit all hallmarks of neurodegeneration including dendrite retraction and axonal swellings, neuron death, astrogliosis, microglia activation, demyelination and decreased adult neurogenesis. Our results uncovered a novel functional network, essential to prevent neurodegeneration, and involving the specific regulation of Sp1 transcription factor and its downstream targets by Trrap-HAT.
2021-02-17 | GSE131213 | GEO
Project description:We inflicted TBI to wildetype (wt) mice in order to establish whether the anti-inflammatory agent cyclophosphamide can be used therapeutically. Cyclophosphamide was found to regulate distinct inflammatory cells such as activated microglia separate from invading phagocytes and dendritic cells. Cyclophosphamide postinjury selectively reduces antigen-presenting dendritic cells. Findings show feasibility of drug development to interfere with brain inflammation.
2014-06-14 | GSE58484 | GEO
Project description:Translational research is commonly performed in the C57B6/J mouse strain, chosen for its genetic homogeneity and phenotypic uniformity. Here, we evaluate the suitability of the white-footed deer mouse (Peromyscus leucopus) as a model organism for aging research, offering a comparative analysis against C57B6/J and diversity outbred (DO) Mus musculus strains. Our study includes comparisons of body composition, skeletal muscle function, and cardiovascular parameters, shedding light on potential applications and limitations of P. leucopus in aging studies. Notably, P. leucopus exhibits distinct body composition characteristics, emphasizing reduced muscle force exertion and a unique metabolism, particularly in fat mass. Cardiovascular assessments showed changes in arterial stiffness, challenging conventional assumptions and highlighting the need for a nuanced interpretation of aging-related phenotypes. Our study also highlights inherent challenges associated with maintaining and phenotyping P. leucopus cohorts. Behavioral considerations, including anxiety-induced responses during handling and phenotyping assessment, pose obstacles in acquiring meaningful data. Moreover, the unique anatomy of P. leucopus necessitates careful adaptation of protocols designed for Mus musculus. While showcasing potential benefits, further extensive analyses across broader age ranges and larger cohorts are necessary to establish the reliability of P. leucopus as a robust and translatable model for aging studies.
| S-EPMC11335981 | biostudies-literature