Project description:Microglia were FACS-isolated from developing mouse corpus callosum at postnatal days 0, 7, and 21, then sequenced by 10X Genomics single-cell sequencing.
Project description:This study defines a molecular interaction between neurons and microglia that drives experience-dependent synapse remodeling in the hippocampus.
Project description:Spatially heterogeneous synapse loss is a characteristic of many psychiatric and neurological disorders, but the underlying mechanisms are unclear. Here, we show that spatially-restricted complement activation mediates stress-induced heterogeneous microglia activation and synapse loss localized to the upper layers of the mouse medial prefrontal cortex (mPFC). Single cell RNA sequencing also reveals a stress-associated microglia state marked by high expression of the apolipoprotein E gene (Apoehigh) localized to the upper layers of the mPFC. Mice lacking complement component C3 are protected from stress-induced layer-specific synapse loss, and the Apoehigh microglia population is markedly reduced in the mPFC of these mice. Furthermore, C3 knockout mice are also resilient to stress-induced anhedonia and working memory behavioral deficits. Our findings suggest that region-specific complement and microglia activation can contribute to the disease-specific spatially restricted patterns of synapse loss and clinical symptoms found in many brain diseases.
Project description:Unilateral whisker lesioning at age P4 leads to removal of thalamocortical synapses in layer IV of the barrel cortex over the course of the next 6 days. Synapse removal is mediated by microglia and induced by CX3CL1-CX3CR1 signaling between neurons and microglia. Downstream of CX3CL1-CX3CR1 activation, microglia induce astrocyte morphological changes. To identify molecular crosstalk between astrocytes and microglia, we performed translating ribosome affinty purification followed by RNA sequencing (TRAP-Seq).