Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA105315 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description: Not available
| S-EPMC8784167 | biostudies-literature
Project description:Expression data from maternally inflamed and Dap12-mutant microglia at E17.5.
| PRJNA212939 | ENA
Project description: Not available
| S-EPMC11335981 | biostudies-literature
Project description:The TREM2-DAP12 receptor complex sustains microglia functions. Heterozygous TREM2 variants subtly impair microglia, facilitating manifestation of Alzheimer’s Disease in the elderly. Homozygous inactivating mutations of TREM2 or DAP12 cause Nasu-Hakola disease (NHD), an early-onset dementia with leukoencephalopathy, myelin loss and gliosis. Here we investigated the impact of DAP12 deficiency in microglia and collateral damage to other brain cells by single-nucleus RNA-seq in NHD patients and DAP12 loss-of-function (KΔ75) mice. KΔ75 mice showed signatures of impaired microglia activation that reverberated in mild dysfunction of other brain cells. Paradoxically, NHD microglia were activated and associated with astrocytosis, hypoxia, and neuronal loss signatures. We envision that KΔ75 signatures recapitulate an early NHD stage in which DAP12-deficient microglia fail to clear toxic products generated during brain development and homeostasis. Conversely, NHD signatures reflect a late disease stage in which accumulated toxic products cause a widespread tissue damage that elicits TREM2-DAP12-independent microgliosis, astrogliosis, hypoxia, and neuronal death. This TREM2-DAP12-independent microglia activation in NHD has bearing on potential microglia-based therapies.
2022-12-31 | GSE190012 | GEO
Project description:The TREM2-DAP12 receptor complex sustains microglia functions. Heterozygous TREM2 variants subtly impair microglia, facilitating manifestation of Alzheimer’s Disease in the elderly. Homozygous inactivating mutations of TREM2 or DAP12 cause Nasu-Hakola disease (NHD), an early-onset dementia with leukoencephalopathy, myelin loss and gliosis. Here we investigated the impact of DAP12 deficiency in microglia and collateral damage to other brain cells by single-nucleus RNA-seq in NHD patients and DAP12 loss-of-function (KΔ75) mice. KΔ75 mice showed signatures of impaired microglia activation that reverberated in mild dysfunction of other brain cells. Paradoxically, NHD microglia were activated and associated with astrocytosis, hypoxia, and neuronal loss signatures. We envision that KΔ75 signatures recapitulate an early NHD stage in which DAP12-deficient microglia fail to clear toxic products generated during brain development and homeostasis. Conversely, NHD signatures reflect a late disease stage in which accumulated toxic products cause a widespread tissue damage that elicits TREM2-DAP12-independent microgliosis, astrogliosis, hypoxia, and neuronal death. This TREM2-DAP12-independent microglia activation in NHD has bearing on potential microglia-based therapies.
2022-12-31 | GSE190013 | GEO
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:Microglia colonize the brain parenchyma at early stages of development and accumulate in specific regions where they actively participate in cell death, angiogenesis, neurogenesis and synapse elimination. A recurring feature of embryonic microglial distribution is their association with developing axon tracts which, together with in vitro data, supports the idea of a physiological role for microglia in neurite development. Yet the demonstration of this role of microglia is still lacking. Here, we have studied the consequences of microglial dysfunction on the formation of the corpus callosum, the largest connective structure in the mammalian brain, which shows consistent microglial accumulation during development. We studied two models of microglial dysfunction: the loss-of-function of DAP12, a key microglial-specific signaling molecule, and a model of maternal inflammation by peritoneal injection of LPS at E15.5. We performed transcriptional profiling of maternally inflamed and Dap12-mutant microglia at E17.5. We found that both treatments principally down-regulated genes involved in nervous system development and function, particularly in neurite formation. We then analyzed the functional consequences of these microglial dysfunctions on the formation of the corpus callosum. We also took advantage of the Pu.1-/- mouse line, which is devoid of microglia. We now show that all three models of altered microglial activity resulted in the same defasciculation phenotype. Our study demonstrates that microglia are actively involved in the fasciculation of corpus callosum axons. To investigate possible roles for microglial during brain development, we challenged microglial function by two complementary approaches. First, we induced maternal inflammation by peritoneal injection of LPS into pregnant dams. Next, we analyzed the consequences of a loss of function of DAP12, a signaling molecule specifically expressed in microglia that is crucial for several aspects of microglia biology (references in Wakselman et al., 2008). We compared the gene expression profiles of microglia from control, maternally-inflamed by LPS (MI), and Dap12-mutated embryos. We isolated RNA from FACS sorted maternally inflamed (by LPS) and Dap12-mutant microglia at E17.5 pooled per pregnant dam; as a control we included PBS treated and untreated (UT) microglia. We compared gene expression between maternally inflamed microlgia (PBSvsLPS) and DAP12-mutant microglia (UTvsDAP12KO).
2014-07-01 | E-GEOD-49079 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the following subset Series: GSE9043: Dap12 microglia GSE9061: Dap12-deficient mouse brain (1 month) Keywords: SuperSeries Refer to individual Series
2011-08-23 | E-GEOD-9083 | biostudies-arrayexpress
Project description: Not available
| S-EPMC4490682 | biostudies-literature
Project description: Not available
| S-EPMC395764 | biostudies-literature