Gene expression data from iPSC-derived astrocytes, comparison
Ontology highlight
ABSTRACT: Alexander disease (AxD) is a fatal neurological illness characterized by white-matter degeneration and formation of Rosenthal fibers, which contain glial fibrillary acidic protein (GFAP) as astrocytic inclusion. AxD is mainly caused by a gene mutation encoding GFAP, although the underlying pathomechanism remains unclear.
Project description:Alexander disease is a rare neurodegenerative disorder caused by mutations in the gene for glial fibrillary acidic protein (GFAP), the major intermediate filament of astrocytes in the central nervous system. GFAP mutation causes a toxic gain-of-function and protein aggregation, ultimately leading to gliosis, astrocyte dysfunction, and neurodegeneration. To better understand the disease process, a rat model has been generated to mimic the common R239H mutation observed in the human disease (R237H in the rat). This study focuses on hippocampus, a brain region with a heavy burden of pathology, to determine the impact of GFAP mutation at presymptomatic (3 weeks of age) and severe stages ( 8 weeks of age) of disease. Transcription profiling shows progressive neuroinflammation and neurodegeneration.
Project description:Olfactory bulb transcript levels for GFAP transgenic mice compared to wildtype at 3wks and 4mos Keywords = GFAP Keywords = Rosenthal fibers Keywords = Alexander disease Keywords: other
Project description:Autoantibodies are crucial for diagnosing central nervous system (CNS) autoimmune disorders. In autoimmune astrocytopathy, autoantibodies targeting astrocytes, such as those against glial fibrillary acidic protein (GFAP) or aquaporin protein 4 (AQP4), serve as indispensable diagnostic markers. Nevertheless, the diagnostic process remains challenging for patients who exhibit astrocytic reactivity on immunological tests but lack detectable specific autoantibodies
Project description:Alexander disease (AxD) is a rare, severe neurodegenerative disorder caused by mutations in the glial fibrillary acidic protein (GFAP). While the exact disease mechanism remains unknown, existing studies suggest that the mutant GFAP influences many cellular processes, including cytoskeleton stability, mechanosensing, cell energetics, and proteasome function. While most studies have primarily focused on GFAP-expressing astrocytes, this protein is also expressed by radial glia and neural progenitor cells, prompting questions about the impact of GFAP mutations on central nervous system (CNS) development. In this study, we present an intriguing observation of an impaired differentiation of astrocytes and neurons in co-cultures of astrocytes and neurons, as well as in brain organoids, both generated from patient-derived induced pluripotent stem (iPS) cells with a GFAP (R239C) mutation. Leveraging single-cell RNA sequencing (scRNA-seq), we identified distinct cell populations and transcriptomic changes between the GFAP mutant cells and an isogenic corrected control. These findings are supported with immunocytochemistry and proteomics. In co-cultures, the AxD mutation resulted in an increased abundance of immature cells, while in organoids, we observed an altered cell differentiation and reduced abundance of astrocytes. Additionally, gene expression analysis associated the AxD mutation with increased stress susceptibility, cytoskeletal abnormalities, and altered extracellular matrix and cell-cell communication patterns. Overall, our results suggest the possibility of a faulty differentiation in human iPS cell-derived models of AxD, opening new avenues for AxD research.
Project description:Chromosomes and genes are non-randomly arranged within the mammalian cell nucleus. Clustering of genes is of great significance in transcriptional regulation. However, the relevance of gene clustering in their expression during differentiation of neural precursor cells (NPCs) into astrocytes remains unclear. We performed a genome-wide enhanced circular chromosomal conformation capture (e4C) to screen genes associated with an astrocyte-specific gene, glial fibrillary acidic protein (Gfap), during astrocyte differentiation. We identified 13 genes that were specifically associated with Gfap and expressed in NPC-derived astrocytes. These results provide evidence for functional significance of gene clustering in transcriptional regulation during NPCs differentiation. comparison of NPCs vs LIF+ vs LIF- cells.
Project description:Chromosomes and genes are non-randomly arranged within the mammalian cell nucleus. Clustering of genes is of great significance in transcriptional regulation. However, the relevance of gene clustering in their expression during differentiation of neural precursor cells (NPCs) into astrocytes remains unclear. We performed a genome-wide enhanced circular chromosomal conformation capture (e4C) to screen genes associated with an astrocyte-specific gene, glial fibrillary acidic protein (Gfap), during astrocyte differentiation. We identified 13 genes that were specifically associated with Gfap and expressed in NPC-derived astrocytes. These results provide evidence for functional significance of gene clustering in transcriptional regulation during NPCs differentiation.
Project description:Oleanolic acid significantly inhibited neurosphere formation in a dose-dependent manner, and achieved a maximum effect at 10 nM. OA also reduced the 5-ethynyl-2’-deoxyuridine (EdU) incorporation into NSCs, indicating an inhibition on proliferation of NSCs. Next, in western blotting analysis, the protein expression of neuron-specific marker tubulin-βⅢ (TuJ1) and Mash1 was increased, while the astrocyte-specific marker glial fibrillary acidic protein (GFAP) decreased. In immunofluorescence analysis, OA significantly elevated the percentage of TuJ1-positive cells and reduced GFAP-positive cells. Using DNA microarrays, 183 genes were found to be differentially regulated by OA.
Project description:The study was aimed at comparing the transcriptome of MG cells of the retina with the progenitors derived from them after an injury. This information will help in the identification of factors that are responsible for the retinal regeneration. Muller glia were isolated by fluorescent activated cell sorting (FACS) using uninjured retinas from transgenice zebrafish (gfap:gfp) where green florescent protein (GFP) is under the control of the glial fibrillary acidic protein (gfap) promoter. MG-derived retinal progenitors were isolated by FACS at 4 days post retinal injury from 1016 tuba1a:gfp transgenic fish where GFP is driven by the tuba1a promoter which is specifically activated in these progenitors. Total RNA was isolated from these cell populations and subjected to microarray analysis to compare their transcriptomes. Samples were prepared in duplicate.
Project description:Oleanolic acid significantly inhibited neurosphere formation in a dose-dependent manner, and achieved a maximum effect at 10 nM. OA also reduced the 5-ethynyl-2M-bM-^@M-^Y-deoxyuridine (EdU) incorporation into NSCs, indicating an inhibition on proliferation of NSCs. Next, in western blotting analysis, the protein expression of neuron-specific marker tubulin-M-NM-2M-bM-^EM-" (TuJ1) and Mash1 was increased, while the astrocyte-specific marker glial fibrillary acidic protein (GFAP) decreased. In immunofluorescence analysis, OA significantly elevated the percentage of TuJ1-positive cells and reduced GFAP-positive cells. Using DNA microarrays, 183 genes were found to be differentially regulated by OA. Neural stem cells derived form mouse embrynic brains were treated with Oleanolic acid or not. Each group had 4 biological relicates each from a mouse.