Isocitrate dehydrogenase 1 mutations drive human gliomagenesis, probably through neomorphic enzyme activity that produces D-2-hydroxyglutarate. To model this disease, we conditionally expressed Idh1R132H in the subventricular zone (SVZ) of the adult mouse brain. The mice developed hydrocephalus and grossly dilated lateral ventricles, with accumulation of 2-hydroxyglutarate and reduced -ketoglutarate. Stem and transit amplifying/progenitor cell populations were expanded, and proliferation increased.Cells expressing SVZ markers infiltrated surrounding brain regions. SVZ cells also gave rise to proliferative subventricular nodules. DNA methylation was globally increased, while hydroxymethylation was decreased. Mutant SVZ cells over-expressed Wnt, cell cycle and stem cell genes, and shared an expression signature with human gliomas. Idh1R132H mutation in the major adult neurogenic stem cell niche causes a phenotype resembling gliomagenesis. Isocitrate dehydrogenase 1 mutations drive human gliomagenesis, probably through neomorphic enzyme activity that produces D-2-hydroxyglutarate. To model this disease, we conditionally expressed Idh1R132H in the subventricular zone (SVZ) of the adult mouse brain. The mice developed hydrocephalus and grossly dilated lateral ventricles, with accumulation of 2-hydroxyglutarate and reduced -ketoglutarate. Stem and transit amplifying/progenitor cell populations were expanded, and proliferation increased. Cells expressing SVZ markers infiltrated surrounding brain regions. SVZ cells also gave rise to proliferative subventricular nodules. DNA methylation was globally increased, while hydroxymethylation was decreased. Mutant SVZ cells over-expressed Wnt, cell cycle and stem cell genes, and shared an expression signature with human gliomas. Idh1R132H mutation in the major adult neurogenic stem cell niche causes a phenotype resembling gliomagenesis.
Expression of Idh1<sup>R132H</sup> in the Murine Subventricular Zone Stem Cell Niche Recapitulates Features of Early Gliomagenesis.
Sex, Age, Specimen part
View SamplesIn this study, we use pre-malignant cells from different Cebpa mutant acute myeloid leukemia (AML) models. We have used conditional KO models (CreLoxP) and isolated hematopoietic cells shortly after induction of recombination, in order to look at pre-leukemic cells, which have acquired the first hit, but not yet undergone full malignant transformation.
Lack of the p42 form of C/EBPα leads to spontaneous immortalization and lineage infidelity of committed myeloid progenitors.
Sex, Specimen part
View SamplesTranscriptional profile of monocytes in the colon in response to C. rodentium infection Overall design: Eight samples have been analyzed. All are from Cd11b+Ly6C+ inflammatory monocytes sorted from colonic tissue 9 days after C. rodentium infection from Atg16L1HM(4) and WT(4) mice.
Autophagy proteins suppress protective type I interferon signalling in response to the murine gut microbiota.
Age, Specimen part, Subject
View SamplesCancer sequencing studies have implicated regulators of pre-mRNA splicing as important disease determinants in Acute Myeloid Leukemia (AML), but the underlying mechanisms have remained elusive. We hypothesized that “non-mutated” splicing regulators may also play a role in AML biology and therefore conducted an in vivo shRNA screen in a mouse model of CEBPA mutant AML. This led to the identification of the splicing regulator RBM25 as a novel tumor suppressor, and down-regulation of RBM25 increased proliferation and decreased apoptosis in human leukemic cell lines. Mechanistically, we could show that RBM25 controlled the splicing of key genes, including those encoding the apoptotic regulator BCL-x and the MYC inhibitor BIN1. Specifically, we demonstrated that RBM25 acts as a regulator of MYC activity and sensitizes cells to increased MYC levels. This mechanism also appears to be operative in human AML patients where RBM25 levels correlative inversely with MYC activity and clinical outcome. Overall design: Examined transcriptome from U937 cells in biological triplicates.
The splicing factor RBM25 controls MYC activity in acute myeloid leukemia.
Specimen part, Cell line, Subject
View SamplesComparison of Arabidopsis seedlings with disturbed function of CDKB2;1 and CDKB2;2 by either overexpression or knock-down
Requirement of B2-type cyclin-dependent kinases for meristem integrity in Arabidopsis thaliana.
Specimen part
View SamplesIn this study, we use a conditional mouse model for Cebpa to investigate the significance of C/EBP in HSCs. The frequency of HSCs is unaltered following deletion of C/EBP, however, upon serial transplantations of either full BM or purified HSCs, the stem cells and stem cell activity is lost. This is not due to increased proliferation, but rather caused by a shift from quiescence to apoptosis with a resultant exhaustion of the stem cell pool. We identify direct C/EBP target genes by combining genome-wide C/EBP ChIP-seq analysis in stem and progenitor cells with gene expression data from HSC with and without C/EBP. Furthermore, we explore the impact of C/EBP on active and repressive histone modifications by doing functional genome-wide ChIP-seq analysis of H3K4Me3 and H3K27Me3 in stem and progenitor cells with and without C/EBP.
C/EBPα is required for long-term self-renewal and lineage priming of hematopoietic stem cells and for the maintenance of epigenetic configurations in multipotent progenitors.
Sex, Specimen part
View SamplesWe explored the transcriptional response to parasitoid attack in Drosophila larvae at nine time points following parasitism, hybridizing five biologic replicates per time point to whole-genome microarrays for both parasitized and control larvae. We found significantly different expression profiles for 159 probe sets (representing genes), and we classified them into 16 clusters based on patterns of co-expression. A series of functional annotations were nonrandomly associated with different clusters, including several involving immunity and related functions. We also identified nonrandom associations of transcription factor binding sites for three main regulators of innate immune responses (GATA/srp-like, NF-kappaB/Rel-like and Stat), as well as a novel putative binding site for an unknown transcription factor. The appearance or absence of candidate genes previously associated with insect immunity in our differentially expressed gene set was surveyed
Genome-wide gene expression in response to parasitoid attack in Drosophila.
Time
View SamplesUnder various pathophysiological muscle-wasting conditions like diabetes and starvation, a family of ubiquitin ligases, including MuRF1 (Muscle specific RING-Finger protein 1), are induced to target muscle proteins for degradation via ubiquitination. In an attempt to identify the in vivo targets of MuRF1 we have generated transgenic mouse lines overexpressing MuRF1 in a skeletal muscle specific fashion. MuRF1-TG lines were viable and had normal fertility. Characterization of their skeletal muscles did not reveal evidence for muscle wasting at 10 weeks of age. In this experiment we compared the skeletal muscle transcriptome of transgenic mice with wildtypes.
MuRF1-dependent regulation of systemic carbohydrate metabolism as revealed from transgenic mouse studies.
Sex, Age, Specimen part
View SamplesIn a whole-transcriptome study, cellular responses of DCs and macrophages confronted with the fungi A. fumigatus, platelet rich plasma (PRP) or the combination of A.fumigatus and PRP were investigated. Therefore DCs and macrophages of three independent donors were harvested after 6 hours co-culture with A. fumigatus, platelet rich plasma (PRP) or the combination of A.fumigatus and PRP and analyzed with Affymetrix whole genome expression arrays. In general, transcriptomic analysis revealed a cell type dependent clustering. Only little effects were obeserved by addition of PRP. Furthermore a clustering of A.fumigatus stimulated cells whether PRP was present or not, was observed. However, significant differences in the immune response of A.fumigauts stimuled DC and macrophages were determined.
Influence of Platelet-rich Plasma on the immune response of human monocyte-derived dendritic cells and macrophages stimulated with Aspergillus fumigatus.
Specimen part
View SamplesLangerhans dendritic cells represent abundantly occuring and evolutionary highly conserved DCs specifically located in the stratified epithelial tissues. LCs are unique among DC family members in that they express epithelial-type adhesion molecules, allowing them to form a tight three-dimensional network in basal and suprabasal epidermal keratinocyte layers and developmentally dependent on the cytokine TGF-1. In the present study, we identified BMP-7 as another key factor inducing LC differnetiation. Here we have performed comparative analysis of highly purified CD207+/CD1a+ in vitro generated Langerhans cells in the presence of BMP-7 and TGF-1. We have identified that both BMP-7-LCs and TGF-1-LCs are closely related to each other.
Identification of bone morphogenetic protein 7 (BMP7) as an instructive factor for human epidermal Langerhans cell differentiation.
Specimen part, Treatment, Subject
View Samples