In a broad range of organisms, Piwi-interacting RNAs (piRNAs) have emerged as core components of a surveillance system that protects the genome by silencing transposable and repetitive elements. A vast proportion of piRNAs is produced from discrete genomic loci, termed piRNA clusters. The molecular mechanisms and the factors that govern the expression of these loci are largely unknown. We have preciously shown the Cutoff (Cuff), a protein with similarity to yeast Rai1, is a component of the piRNA pathway. In order to understand the function of the Cuff protein in piRNA production, we produced small RNA libraries from cn, bw (wt) and cuffwm25 mutant ovaties. The analysis of these libraries revealed that approximately 80% of the total piRNA population is depleted in the absence of a functional Cuff protein. We also determined that Cuff is mostly a nuclear protein and is enriched at the level of certain piRNA clusters. Our results point to a role for Cuff in the transcriptional regulation of piRNA generating loci and in the production of the proper piRNA complement during Drosophila oogenesis. Overall design: piRNA profiling in ovaries from cn, bw and cuffwm25 mutant ovaries
The Cutoff protein regulates piRNA cluster expression and piRNA production in the Drosophila germline.
Specimen part, Subject
View SamplesTwo-dimensional patterning of the follicular epithelium in Drosophila oogenesis is required for the formation of three-dimensional eggshell structures. Our analysis of a large number of published gene expression patterns in the follicle cells suggests that they follow a simple combinatorial code based on six spatial building blocks and the operations of union, difference, intersection, and addition. The building blocks are related to the distribution of inductive signals, provided by the highly conserved epidermal growth factor receptor and Decapentaplegic
A combinatorial code for pattern formation in Drosophila oogenesis.
No sample metadata fields
View SamplesWNT-induced secreted protein 1 (WISP1/CCN4), a member of the CCN protein family, acts as a downstream factor of the canonical WNT-signaling pathway. A dysregulated expression of WISP1 often reflects its oncogenic potential by inhibition of apoptosis, a necessary form of cell death that protect cell populations for transformation into malignant phenotypes. WISP1-signaling is also known to affect proliferation and differentiation of human mesenchymal stem cells (hMSCs), which are fundamental for the constitution and maintenance of the musculoskeletal system. Our study emphasizes the importance of WISP1-signaling for cell survival of primary human cells. Therefore, we established a successful down-regulation of endogenous WISP1 transcripts through gene silencing in hMSCs. We were able to demonstrate the consequence of cell death immediately after WISP1 down-regulation took place. Bioinformatical analyses of subsequent performed microarrays from WISP1 down-regulated vs. control samples confirmed this observation. We uncovered several clusters of differential expressed genes important for cellular apoptosis induction and immuno-regulatory processes, thereby indicating TRAIL-induced and p53-mediated apoptosis as well as IFNbeta-signaling. Since all of them act as potent inhibitors for malignant cell growth, in vitro knowledge about the connection with WISP1-signaling could help to find new therapeutic approaches concerning cancerogenesis and tumor growth in musculoskeletal tissues.
WISP 1 is an important survival factor in human mesenchymal stromal cells.
Specimen part, Treatment
View SamplesDiffuse large B-cell lymphoma (DLBCL) represents the most common form of lymphoma. We could show that in DLBCL cell lines the transcription factor NFAT is constitutively activated and drives the survival of a DLBCL subset. Aim of the analysis was to identify NFAT target genes in a NFAT-dependent (HBL-1) or -independent (HT) DLBCL cell line. To block NFAT activity, the DLBCL cells were treated with the calcineurin inhibitor cyclosporin A (CsA) up to 48 h. With this approach, we identified several survival-related NFAT target genes in HBL-1 cells that might explain the toxic effects of calcineurin inhibitors.
Targeting chronic NFAT activation with calcineurin inhibitors in diffuse large B-cell lymphoma.
Treatment
View SamplesConditional ablation of Ezh2 in the neural crest lineage results in loss of the neural crest-derived mesenchymal derivatives. In this data sheet we determine gene expression analysis in Ezh2lox/lox and Wnt1Cre Ezh2lox/lox in E11.5 mouse BA1 cells.
Ezh2 is required for neural crest-derived cartilage and bone formation.
Specimen part
View SamplesGene expression profiling of surgical biopsies from 74 breast cancer patients of different subtypes from Hamburg dataset.
Prognostic relevance of glycosylation-associated genes in breast cancer.
Sex, Specimen part
View SamplesIn this study we analyzed the myeloma cell contact-mediated changes on the transcriptome of skeletal precursor cells. Therefore, human mesenchymal stem cells (MSC) and osteogenic precursor cells (OPC) were co-cultured with the representative myeloma cell line INA-6 for 24 h. Afterwards, MSC and OPC were separated from INA-6 cells by fluorescence activated cell sorting. Total RNA of MSC and OPC fractions was used for whole genome array analysis.
Contact of myeloma cells induces a characteristic transcriptome signature in skeletal precursor cells -Implications for myeloma bone disease.
Sex, Age, Specimen part, Disease stage
View SamplesThe aim of the study is to identify AR target gens in LNCaP cells Overall design: 6 samples correponding to 2 times 3 replicates were used for the study
Assembly of methylated KDM1A and CHD1 drives androgen receptor-dependent transcription and translocation.
No sample metadata fields
View SamplesOrganisms need to assess their nutritional state and adapt their digestive capacity to the demands for various nutrients. Modulation of digestive enzyme production represents a rational step to regulate nutriment uptake. However, the role of digestion in nutrient homeostasis has been largely neglected. In this study, we analyzed the mechanism underlying glucose repression of digestive enzymes in the adult Drosophila midgut. We demonstrate that glucose represses the expression of many carbohydrases and lipases. Our data reveal that the consumption of nutritious sugars stimulates the secretion of the transforming growth factor ß (TGF-ß) ligand, Dawdle, from the fat body. Dawdle then acts via circulation to activate TGF-ß/Activin signaling in the midgut, culminating in the repression of digestive enzymes that are highly expressed during starvation. Thus, our study not only identifies a mechanism that couples sugar sensing with digestive enzyme expression but points to an important role of TGF-ß/Activin signaling in sugar metabolism. Overall design: RNA-sequencing of whole guts from Drosophila melannogaster OregonR adult females was performed under three feeding conditions: Standard medium, glucose, and agar. Three biological repeats were performed for each condition.
Transforming growth factor β/activin signaling functions as a sugar-sensing feedback loop to regulate digestive enzyme expression.
Specimen part, Cell line, Subject
View SamplesThe replication of a genomic region during S-phase can be highly dynamic between cell types that differ in transcriptome and epigenome. Replication timing has been positively correlated with several histone modifications that occur at active genes, while repressive histone modifications mark late replicating regions. This raises the question if chromatin modulates the initiating events of replication. To gain insights into this question we have studied the function of heterochromatin protein 1 (HP1), a reader of to the repressive histone lysine 9 methylation of H3, in genome-wide organization of replication. Cells with reduced levels of HP1 show an advanced replication timing of centromeric repeats in agreement with the model that repressive chromatin mediates the very late replication of large clusters of constitutive heterochromatin. Surprisingly however regions with high levels of interspersed repeats on the chromosomal arms in particular on chromosome 4 and in pericentromeric regions of chromosome 2 behave differently. Here loss of HP1 results in delayed replication timing. The fact that these regions are bound by HP1 suggests a direct effect. Thus while HP1 mediates very late replication of centromeric DNA it is also required for early replication of autosomal regions with high levels of repeats. This observation of opposing functions of HP1 suggests a model where repeat inactivation on autosomes is required for proper activation of origins of replication that fire early, while HP1 mediated repression at constitutive heterochromatin is required to ensure replication of centromeric repeats at the end of S phase.
Heterochromatin protein 1 (HP1) modulates replication timing of the Drosophila genome.
Sex, Specimen part
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