In humans, the most common sex chromosomal disorder is Klinefelter syndrome (KS), caused by the presence of one or more extra X-chromosomes. The KS patients display a diverse adult phenotype with increased height, gynaecomastia, and hypergonadotropic hypogonadism as the most common symptoms. Men with KS are almost always infertile due to testicular degeneration, which accelerates during puberty. Very few studies investigated when the germ cell loss begins and whether it is caused by dysgenetic fetal development of the testes. We investigated a series of fetal KS testis tissue samples and found a marked reduction in MAGE-A4-positive pre-spermatogonia in the developing KS gonads compared to controls, indicating a failure of the gonocytes to differentiate into pre-spermatogonia. Transcriptome analysis by RNA sequencing of formalin-fixed and paraffin embedded gonads originating from 4 fetal KS samples and 5 age- and cellularity-matched controls revealed 211 differentially expressed transcripts in the fetal KS testis. We found a significant enrichment of upregulated X-chromosomal transcripts and validated the expression of the pseudoautosomal region 1 (PAR1) gene, AKAP17A. Moreover, we found enrichment of long non-coding RNAs in the KS testes (e.g. LINC01569 and RP11-485F13.1). In conclusion, our data indicates that the testicular phenotype observed among adult men with KS is initiated already in fetal life by failure of the gonocyte differentiation into pre-spermatogonia, which could be due to aberrant expression of long non-coding RNAs. Overall design: Includes a total of 9 samples. 4 fetal Klinefelter and 5 age-matched controls testis samples
Transcriptome profiling of fetal Klinefelter testis tissue reveals a possible involvement of long non-coding RNAs in gonocyte maturation.
Subject
View SamplesSporadic Creutzfeldt-Jakob disease (sCJD) is the most prevalent form of human prion disease and it is characterized by the presence of neuronal loss, spongiform degeneration, chronic inflammation and the accumulation of misfolded and pathogenic prion protein (PrPSc). The molecular mechanisms underlying these alterations are largely unknown, but the presence of intracellular neuronal calcium (Ca+2) overload, a general feature in models of prion diseases, is suggested to play a key role in prion pathogenesis. Here we describe the presence of massive regulation of Ca+2 responsive genes in sCJD brain tissue, accompanied by two Ca+2-dependent processes: endoplasmic reticulum stress and the activation of the cysteine proteases Calpains 1/2. Pathogenic Calpain activation in sCJD is linked to the cleavage of their cellular substrates, impaired autophagy and lysosomal damage, which is partially reversed by Calpain inhibition in a cellular prion model. Calpain 1 treatment enhances seeding activity of PrPSc in a prion conversion assay. Neuronal lysosomal impairment caused by Calpain over activation leads to the release of the lysosomal protease Cathepsin S that in sCJD mainly localises in axons. Additionally, massive Cathepsin S overexpression is detected in microglial cells. Alterations in Ca+2 homeostasis and activation of Calpain-Cathepsin axis already occur at pre-clinical stages of the disease as detected in a humanized sCJD mouse model. Altogether our work indicates that unbalanced Calpain-Cathepsin activation is a relevant contributor to the pathogenesis of sCJD at multiple molecular levels and a potential target for therapeutic intervention. Overall design: To identify differentially expressed genes during development of sCJD pathology we analysed the expression levels in the cortical region of tg340-PRNP129MM mice infected with sCJD MM1 brain homogenates at pre-clinical (120 dpi) and clinical (180 dpi) stages.
Altered Ca<sup>2+</sup> homeostasis induces Calpain-Cathepsin axis activation in sporadic Creutzfeldt-Jakob disease.
Subject, Time
View SamplesThe ability to form memories is a prerequisite for an organism’s behavioural adaptation to environmental changes. At the molecular level, the acquisition and maintenance of memory requires changes in chromatin modifications. In an effort to unravel the epigenetic network underlying both short- and long-term memory, we examined chromatin modification changes in two distinct mouse brain regions, two cell-types, and three time-points before and after contextual learning. Here we show that histone modifications predominantly change during memory acquisition and correlate surprisingly little with changes in gene expression. While long-lasting changes are almost exclusive to neurons, learning-related histone modification and DNA methylation changes occur also in non-neuronal cell types, suggesting a functional role for non-neuronal cells in epigenetic learning. Finally, our data provides evidence for a molecular framework of memory acquisition and maintenance, wherein DNA methylation could alter the expression and splicing of genes involved in functional plasticity and synaptic wiring. Overall design: We examined chromatin modification changes in two distinct mouse brain regions (CA1 and ACC), two cell-types (neurons, non-neurons), and three time-points before and after contextual learning (naive, 1h, 4w).
DNA methylation changes in plasticity genes accompany the formation and maintenance of memory.
Sex, Age, Cell line, Subject
View SamplesIn humans, the most common sex chromosomal disorder is Klinefelter syndrome (KS), caused by the presence of one or more extra X-chromosomes. The KS patients display a diverse adult phenotype with increased height, gynaecomastia, and hypergonadotropic hypogonadism as the most common symptoms. Men with KS are almost always infertile due to testicular degeneration, which accelerates during puberty. Very few studies investigated the global gene expression analysis of adult KS testes and, more importantly, which cell types the differentially expressed transcripts originate from. Transcriptome analysis by RNA sequencing of fixed and paraffin embedded testes originating from 3 adult KS samples and 3 adult cellularity-matched controls revealed 236 differentially expressed transcripts in the adult KS testis. To examine the cellular origin of the differentially expressed transcripts, transcriptome profiling was also carried out on 4 testes with Sertoli Cell-Only and 4 testes with full spermatogenesis. Also, pre-pubertal KS and controls were RNA-sequenced. Overall design: Includes a total of 22 testis samples. 3 adult Klinefelter, 3 Klinefelter-like, 4 Sertoli Cell-Only, 4 with full spermatogenesi, 4 pre-pubertal Klinefelter and 4 pre-pubertal controls
Transcriptome analysis of the adult human Klinefelter testis and cellularity-matched controls reveals disturbed differentiation of Sertoli- and Leydig cells.
Specimen part, Subject
View SamplesThe gastrointestinal (GI) tract can have significant impact on the regulation of the whole body metabolism and may contribute to the development of obesity and diabetes. To systemically elucidate the role of the GI tract in obesity, we performed a transcriptomic analyses in different parts of the GI tract of two obese mouse models: ob/ob and high-fat diet (HFD) fed mice. Compared to their lean controls, both obese mouse groups had significant amount of gene expression changes in the stomach (ob/ob: 959; HFD: 542), much more than the number of changes in the intestine. Despite the difference in genetic background, the two mouse models shared 296 similar gene expression changes in the stomach. Among those genes, some had known associations to obesity, diabetes and insulin resistance. In addition, the gene expression profile strongly suggested an increased gastric acid secretion in both obese mouse models, probably through an activation of the gastrin pathway. In conclusion, our data reveal a previously unknown dominant connection between the stomach and obesity.
Significant obesity-associated gene expression changes occur in the stomach but not intestines in obese mice.
Specimen part
View SamplesGlioblastoma multiforme (GBM) is the most malignant and most common tumor of the central nervous system characterized by rapid growth and extensive tissue infiltration. GBM results in more years of life lost than any other cancer type. Notch signaling has been implicated in GBM pathogenesis through several modes of action. Inhibition of Notch leads to a reduction of cancer-initiating cells in gliomas and reduces proliferation and migration. Deltex1 (DTX1) is part of an alternative Notch signaling pathway distinct from the canonical MAML1/RBPJ-mediated cascade. In this study, we show that DTX1 activates both the RTK/PI3K/PKB as well as the MAPK/ERK pathway. Moreover, we found the anti-apoptotic factor Mcl-1 to be induced by DTX1. In accordance with this, the clonogenic potential and proliferation rates of glioma cell lines correlated with DTX1 levels. DTX1 knock down mitigated the tumorigenic potential in vivo, and overexpression of DTX1 increased cell migration and invasion of tumor cells accompanied by an elevation of the pro-migratory factors PKB and Snail1. Microarray gene expression analysis identified a DTX1-specific transcriptional program - including microRNA-21 - which is distinct from the canonical Notch signaling. We propose the alternative Notch pathway via DTX1 as oncogenic factor in malignant glioma and found low DTX1 expression levels to correlate with prolonged survival of GBM and early breast cancer patients in open source databases.
Deltex-1 activates mitotic signaling and proliferation and increases the clonogenic and invasive potential of U373 and LN18 glioblastoma cells and correlates with patient survival.
Specimen part, Cell line
View SamplesUsing a novel class of chemically-engineered oligonucleotides, termed "antagomirs", we studied the biological significance of silencing miR-122 in the liver of mice at the mRNA level
Silencing of microRNAs in vivo with 'antagomirs'.
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View SamplesThe goal of the study was to sequence mRNA expression from sorted medullary thymic epithelial cell (mTEC) subsets in inducible Aire-CreERT2.R26-Stopfl-tdTomato lineage tracing mice after a pulse chase. Four cell subsets were sorted 7 days after a single 2mg pulse of tamoxifen administered by oral gavage. 4 biological replicates (1,2,3,4) were collected derived from 12 pooled thymi per replicate. From the DAPI-;CD45-;EpCAM+ TEC pool, cells were sorted as: pre-Aire (MHCIIlo;RFP-), early-Aire (MHCIIhi;RFP-), late-Aire (MHCIIhi;RFP+), and post-Aire (MHCIIlo;RFP+). The data were used to identify differentially expressed genes across the four mTEC subsets to examine mTEC heterogeneity and identify novel mTEC subpopulations. Overall design: Four biological replicates (12 pooled thymi per replicate) of each of four mTEC subsets were sorted from Aire-lineage tracing mice 7 days after pulse-chase with tamoxifen.
Thymic tuft cells promote an IL-4-enriched medulla and shape thymocyte development.
Sex, Specimen part, Cell line, Subject
View SamplesThe goal of this study was to investigate DNA methylation and gene expression changes in a zebrafish model of ICF Syndrome which were generated by mutation of ICF-gene zbtb24. Comparison of gene expression changes between wildtype and zbtb24 homozygous mutants revealed upregulation of interferon response genes following zbtb24 deletion. Upregulation of interferon response genes was blocked by mutation of the dsRNA helicase Mda5. Overall design: For RNA-seq, gene expression was compared in whole two-week-old zebrafish larvae that were wildtype or homozygous for the zbtb24mk22 mutant allele. We further performed RNA-Seq analysis in three-week-old zebrafish larvae that were WT, mda5mk29/mk29 , zbtb24mk22/mk22 and mda5mk29/mk29 ;zbtb24mk22/mk22. Three samples consisting of pools of 10 larvae were examined for each genotype. For ERRBS, DNA was separately isolated from the fins of three wildtype and three zbtb24mk22 homozygous mutant adults.
Pericentromeric hypomethylation elicits an interferon response in an animal model of ICF syndrome.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
TPL-2-ERK1/2 signaling promotes host resistance against intracellular bacterial infection by negative regulation of type I IFN production.
Specimen part
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