Aging is a key factor in Alzheimer''s disease, but it''s correlation with the pathology and pathological factors like amyloid-beta remains unclear In our study we aimed to provide an extensive characterisation of age-related changes in the gene expression profile of APP23 mice and controls and correlate these changes to pathological and symptomatic features of the model We found a clear biphasic expression profile with a developmental and aging phase. The second phase, particularly, displays aging features and similarties with the progression of Alzheimer pathology in human patients Processes involved in microglial activation, lysosomal processing, neuronal differantion and cytoskeletal regulation appear key factors in this stage. Interestingly, the changes in the gene expression profile of APP23 mice also seem to occur in control animals, but at a later age. The changes appear accelerated and/or exacerbated in APP23 mice. Overall design: mRNA profiles of APP23 mice and wild-type control littermates aged 1.5, 6, 18 or 24 months. For all the age groups, samples of 3 mice of each genotype were analyzed
Aging, microglia and cytoskeletal regulation are key factors in the pathological evolution of the APP23 mouse model for Alzheimer's disease.
Age, Specimen part, Subject
View SamplesPurpose: Identify zebrafish microglia transcriptome in the healthy and neurodegenerative brain. Methods: RNA sequencing was performed on FACS-sorted microglia (3x), other brain cells (3x) and activated microglia (4x). Microglia activation was induced using nitroreductase-mediated cell ablation. 10-20 million reads per sample were obtained. Reads were mapped to zebrafish genome GRC10. Results: We identified the zebrafish microglia transcriptome, which shows overlap with previously identified mouse microglia transcriptomes. Transcriptomes obtained 24h and 48h after treatment appeared highly similar. Therefore, these datasets were pooled. Additionally, we identified an acute proliferative response of microglia to induced neuronal cell death. Overall design: Zebrafish microglia transcriptomes of homeostatic microglia (triplicate), other brain cells (triplicate), activated microglia 24h (duplo), activated microglia 48h (duplo). In data analysis all activated microglia samples were pooled.
Identification of a conserved and acute neurodegeneration-specific microglial transcriptome in the zebrafish.
No sample metadata fields
View SamplesBackground: Tissue macrophages contribute to development and protection, both requiring appropriately timed and located source(s) of factors controlling growth, cell differentiation and migration. Goal: To understand the role of microglia (tissue macrophages of the central nervous system), in promoting neurodevelopment and controlling neuroinflammation. Summary of findings: We show that microglia fulfill both these roles. In contrast to adult cells, neonatal microglia show a unique neurogenic phenotype with stem cell-like potential. Neonatal microglia are protective against neuroinflammation, and their transplantation ameliorates experimental autoimmune encephalomyelitis. A CD11c+ microglial subset predominates in primary myelinating areas of the developing brain and expresses genes for neuronal and glial survival, migration and differentiation. CD11c+ microglia are also found in clusters of repopulating microglia after experimental ablation and in neuroinflammation in adult mice, but despite some similarities, they do not recapitulate neurogenic neonatal microglia characteristics. Conclusions: We therefore identify a unique phenotype of neonatal microglia that deliver signals necessary for neurogenesis and myelination and suppress neuroinflammation. Overall design: The overall design was to compare transcriptomes of subsets of microglia isolated from neonatal mice, healthy adults, and adult mice with a neuroinflammatory disease (Experimental autoimmune encephalomyelitis, EAE), and to compare anti-inflammatory function of adult and neonatal microglia. Microglia were isolated by cell-sorting based on surface phenotype, and RNAseq data was analyzed using WGCNA, GO and DAVID approaches. Expression of selected genes and pathways was confirmed by histology and flow cytometry. Functional analysis involved transfer of isolated microglia to the central nervous system of animals with EAE and evaluation of outcome. EAE = Experimental autoimmune encephalomyelitis
A novel microglial subset plays a key role in myelinogenesis in developing brain.
Subject
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Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma.
Specimen part, Treatment
View SamplesSUMMARY Despite numerous genome-wide association studies involving glioblastoma (GBM), few therapeutic targets have been identified for this disease. Using patient derived glioma sphere cultures (GSCs), we have found that a subset of the proneural (PN) GSCs undergo transition to a mesenchymal (MES) state in a TNFa/NFkB dependent manner with an associated enrichment of CD44 sub-populations and radio-resistant phenotypes. To the contrary, MES GSCs exhibit constitutive NFkB activation, CD44 enrichment and radio-resistance. Patients whose tumors exhibit a higher MES metagene, increased expression of CD44, or activated NFkB were associated with poor radiation response and shorter survival. Our results indicate that NFkB activation mediated MES differentiation and radiation resistance presents an attractive therapeutic target for GBM.
Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma.
Specimen part
View SamplesSUMMARY Despite numerous genome-wide association studies involving glioblastoma (GBM), few therapeutic targets have been identified for this disease. Using patient derived glioma sphere cultures (GSCs), we have found that a subset of the proneural (PN) GSCs undergo transition to a mesenchymal (MES) state in a TNFa/NFkB dependent manner with an associated enrichment of CD44 sub-populations and radio-resistant phenotypes. To the contrary, MES GSCs exhibit constitutive NFkB activation, CD44 enrichment and radio-resistance. Patients whose tumors exhibit a higher MES metagene, increased expression of CD44, or activated NFkB were associated with poor radiation response and shorter survival. Our results indicate that NFkB activation mediated MES differentiation and radiation resistance presents an attractive therapeutic target for GBM.
Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma.
Specimen part, Treatment
View SamplesFusarium Head Blight susceptible barley variety, Morex, was infected with deoxynivalenol production deficient mutant strain (GZT40) and wild type stains (Z3639) of Fusarium graminearum. The RNA was sampled at 48 and 96 hours after inoculation. and was used hybridize to Barley_1 GeneChip. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Jayanand Boddu. The equivalent experiment is BB52 at PLEXdb.]
Transcriptome analysis of trichothecene-induced gene expression in barley.
Specimen part
View SamplesBarley cv. Morex inoculated with Fusarium graminearum (isolate Butte 86) or water (mock). Sampled at 24, 48, 72, 96 and 144 hours after treatment. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Jayanand Boddu. The equivalent experiment is BB9 at PLEXdb.]
Transcriptome analysis of the barley-Fusarium graminearum interaction.
Specimen part, Time
View SamplesToxoplasma gondii is an obligate intracellular Apicomplexan parasite capable of invading and surviving within nucleated cells in most warm-blooded animals. This remarkable task is achieved through the delivery of effector proteins from the parasite into the parasitophorous vacuole and host cell cytosol that rewire host cellular pathways, facilitating parasite evasion of the immune system. Here, we have identified a novel export pathway in Toxoplasma that involves cleavage of effector proteins by the Golgi-resident aspartyl protease 5 (ASP5) prior to translocation into the host cell. We demonstrate that ASP5 cleaves a highly constrained amino acid motif that has some similarity to the PEXEL motif of Plasmodium parasites. We show that ASP5 can mature effectors at both the N- and C-terminal ends of proteins and is also required for the trafficking of proteins without this motif. Furthermore, we show that ASP5 controls establishment of the nanotubular network and is required for the efficient recruitment of host mitochondria to the parasitophorous vacuole membrane. Global assessment of host gene expression following infection reveals that ASP5-dependent pathways influence thousands of the transcriptional changes that Toxoplasma imparts on its host cell. This work characterizes the first identified machinery required for export of Toxoplasma effectors into the infected host cell. Overall design: Three groups of human foreskin fibroblasts are compared. Each group has 3 replicates giving a total of 9 samples. The first group of samples are infected with wild type (GRA16HA) Toxoplasma gondii, the second group with Asp5 knock-out Toxoplasma gondii, and the final group remain uninfected. All fibroblasts are generated from one donor sample.
An aspartyl protease defines a novel pathway for export of Toxoplasma proteins into the host cell.
No sample metadata fields
View SamplesThe putative trancriptional regulator PA2449 was found to be essential for both glycine/serine metabolism and the production of phenazines in P. aeruignosa PAO1.
Gene PA2449 is essential for glycine metabolism and pyocyanin biosynthesis in Pseudomonas aeruginosa PAO1.
No sample metadata fields
View Samples