Project description:Protoplasmic astrocytes in layers II to VI of the mammalian neocortex have historically been thought to comprise a homogeneous population. Given that layer-specific neuronal subtypes play essential roles in cortical circuitry, astrocytes might also be expected to support and modify this circuitry in a layer-specific manner. In order to investigate whether protoplasmic astrocytes exhibit layer-specific heterogeneity, we compared the gene expression profiles of astrocytes between upper layers (layers II to IV) and deep layers (layers V and VI). Although most genes known to be preferentially expressed in astrocytes (astrocyte-enriched genes) were equally expressed between upper-layer astrocytes and deep-layer astrocytes, some such genes (astrocyte-enriched genes or genes with known function in astrocytes) were significantly enriched in upper-layer astrocytes or deep-layer astrocytes.
Project description:Affymetrix Mouse Genome 430 2.0 GeneChip microarrays were used to analyze murine neocortical and cerbellar astrocytes generated from postnatal (PN) day 1 wild-type (ICR) pups. Experiment Overall Design: Three samples each of murine neocortical and cerebellar astrocytes were analyzed.
Project description:Affymetrix Mouse Genome 430 2.0 GeneChip microarrays were used to analyze murine neocortical and cerbellar astrocytes generated from postnatal (PN) day 1 wild-type (ICR) pups. Keywords: neocortical astrocyte, cerebellar astrocyte, murine, postnatal day 1
Project description:Neuronal cell diversity is essential to endow distinct brain regions with specific functions. During development, progenitors within these regions are characterised by specific gene expression programs, contributing to the generation of diversity in postmitotic neurons and glia. While the region-specific molecular diversity of neurons and astrocytes is increasingly understood, whether these cells share region-specific programs remains unknown. Here, we show that in the neocortex and thalamus, neurons and astrocytes express shared region-specific transcriptional and epigenetic signatures. These signatures not only distinguish cells across brain regions but are also detected across substructures within regions, such as distinct thalamic nuclei, where clonal analysis reveals the existence of common nucleus-specific progenitors for neurons and glia. Consistent with their shared molecular signature, regional specificity is maintained following astrocyte-to-neuron reprogramming. A detailed understanding of these regional-specific signatures may thus inform strategies for future cell-based brain repair.
Project description:To investigate the functional heterogeneity of astrocytes from a defined brain region, we designed 12 experimental manipulations including Huntington's disease models, pathological challenges, ionic and GPCR signaling alterations, and analyzed the transcriptomic profiles of striatal astrocytes. From the analyses, we have identified context-specific changes of striatal astrocytes.