Using measles virus induced T cell suppression as a model, we established that T cell inhibitory protein isoforms can be produced from alternatively spliced pre-mRNAs as a result of virus-mediated ablation of T cell receptor dependent activation of the phosphatidylinositol-3-kinase (PI3K). To asses production of alternative splice variants in response to PI3K abrogation in T cells at a whole cell level, we performed a Human Exon 1.0 ST Array on RNAs isolated from T cells stimulated only or stimulated after PI3K inhibition. We developed a simple algorithm based on a splicing index to detect genes that undergo alternative splicing (AS) or are differentially regulated (RG) on T cell suppression. Applying our algorithm on this model 9% of the genes were assigned as AS, while only 3% were attributed to RG. Though there are overlaps, AS and RG genes differed with regard to functional regulated at the level of AS or RG were found enriched in different functional groups with AS targeting e. g. extra cellular matrix (ECM)-receptor interaction and focal adhesion, while cytokine-receptor interaction, Jak-STAT and p53 pathways were mainly RG. When combined, AS/RG dependent alterations targeted pathways essential for T cell receptor signaling, cytoskeletal dynamics and cell cycle entry strongly supporting the notion that PI3K abrogations interferes with key T cell activation processes at both levels, and that candidates represented within both categories bear the potential to actively contribute to T cell suppression
Accumulation of splice variants and transcripts in response to PI3K inhibition in T cells.
Specimen part, Treatment, Subject
View SamplesPurpose: CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal AML (CN-AML).
Acute myeloid leukemia with biallelic CEBPA gene mutations and normal karyotype represents a distinct genetic entity associated with a favorable clinical outcome.
Specimen part
View SamplesThe goal of this study is to perform RNAseq in different sub-types of the zebrafish embryonic dorsal aorta (DA) at 28-30 hpf using TgBAC(runx1P2:Citrine);Tg(kdrl:mCherry) double-transgenic zebrafish embryos. A min. of 3000 cells per population were collected via FACS. RNA was isolated with the RNeasy Plus Micro Kit (QIAGEN, Cat No. 74034). High quality RNA (RIN > 8.0) was sent for RNAseq to the Wellcome Trust Centre for Human Genetics (WTCHG). 2.2 ng of total RNA was used to generate SMARTer libraries for low-input RNA. Sequencing was performed on an Illumina HiSeq4000 machine with a 75 bp paired end protocol. Sequenced reads were checked for base qualities, trimmed where 20% of the bases were below quality score 20, and filtered to exclude adapters using Trimmomatic (Version 0.32). Sequences were aligned to the Zebrafish Genome Zv10 with STAR with default parameters. Aligned read features were counted using Subread tool: featureCounts method (version 1.4.5-p1). To determine number of mapped reads we used the trimmed data. The alignment has been performed using STAR with default parameters. The number of mapped reads (QC-passed reads count) has been obtain using Samtools mapping statistics (flagstat tool). Overall design: Analysis of 5 different cell types; DN (double negative), SP-kdrl (single positive), DP-R1lo (double positive runx1 low expression), DP-R1med (runx1 medium expressionand) and DP-R1hi (runx1 high expression) in non-injected (Wt) TgBAC(runx1P2:Citrine);Tg(kdrl:mCherry) double-transgenic zebrafish embryos. Analysis was also done of the DN and DP-R1hi populations in runx1-morpholino (MO) injected embryos.
Blood stem cell-forming haemogenic endothelium in zebrafish derives from arterial endothelium.
Specimen part, Subject
View SamplesThe activity of chaperone-mediated autophagy (CMA), a catabolic pathway for selective degradation of cytosolic proteins in lysosomes, decreases with age, but the consequences of this functional decline in vivo remain unknown. In this work, we have generated a conditional knockout mouse to selectively block CMA in liver. We have found that blockage of CMA causes hepatic glycogen depletion and hepatosteatosis. The liver phenotype is accompanied by reduced peripheral adiposity, increased energy expenditure, and altered glucose homeostasis. Comparative lysosomal proteomics revealed that key enzymes in carbohydrate and lipid metabolism are normally degraded by CMA and that impairment of this regulated degradation contributes to the metabolic abnormalities observed in CMA-defective animals. These findings highlight the involvement of CMA in regulating hepatic metabolism and suggest that the age-related decline in CMA may have a negative impact on the energetic balance of old organisms.
Deficient chaperone-mediated autophagy in liver leads to metabolic dysregulation.
Specimen part
View SamplesSmac mimetics are considered as promising cancer therapeutics, but little is yet known about how they alter gene expression. In this study we used an unbiased genome-wide expression array to investigate Smac mimetic BV6-induced gene regulation in breast cancer cell lines. Kinetic analysis revealed that BV6 alters gene expression in two waves. The first wave primarily involves NF-B- and AP-1 families of transcription factors, while the second wave largely depends on tumor necrosis factor receptor 1 (TNFR1) signaling. Interestingly, disrupting auto-/paracrine tumor necrosis factor- (TNF)/ (TNFR1) signaling by knockdown of TNFR1 strongly attenuates the BV6-induced second wave of gene expression and upregulation of many pathways including NF-B signaling, apoptosis and immune signalling, but not MAPK signaling pathways. Consistently, BV6 stimulates phosphorylation of cJun, a marker of MAPK cascade activation, irrespective of the presence or absence of the TNF blocking antibody Enbrel. We show here in a comprehensive overview that BV6-induced gene expression in breast cancer cells takes place in a time- as well as TNFR1-dependent manner.
Smac mimetic induces an early wave of gene expression via NF-κB and AP-1 and a second wave via TNFR1 signaling.
Cell line, Treatment
View SamplesBackground: Isolation and characterization of tumourigenic colon cancer initiating cells may help to develop novel diagnostic and therapeutic procedures. Methods: We characterized a panel of fourteen human colon carcinoma cell lines and their corresponding xenografts for the surface expression of different potential stem cell markers: CD133, CD24, CD44, CDCP1 and CXCR4. In five cell lines and nine xenografts mRNA expression of the investigated markers was determined. Tumour growth behaviour of CD133+, CD133- and unsorted SW620 cells was evaluated in vivo. Results: All surface markers showed distinct expression patterns in the examined tumours. Analyses of the corresponding xenografts revealed a significant reduction of cell numbers expressing the investigated markers. CD44 and CXCR4 mRNA expression correlated within the cell line panel and CD44 and CDCP1 within the xenograft panel, respectively. Small subpopulations of double and triple positive cells could be described. SW620 showed significantly higher take rates and shorter doubling times in vivo when sorted for CD133 positivity. Conclusion: Our data support the hypothesis of a small subset of cells with stem cell-like properties characterized by a distinct surface marker profile. In vivo growth kinetics give strong relevance for an important role of CD133 within the mentioned surface marker profile.
Characterization of colon cancer cells: a functional approach characterizing CD133 as a potential stem cell marker.
Sex, Age, Specimen part
View SamplesTranscriptom analysis of stellate sympathetic ganglia after 8 weeks of cardiac pressure overload caused by transverse aortic constriction.
Sympathetic alpha(2)-adrenoceptors prevent cardiac hypertrophy and fibrosis in mice at baseline but not after chronic pressure overload.
Sex
View SamplesThe cellular response to DNA damage is mediated through multiple pathways that regulate and coordinate DNA repair, cell cycle arrest and cell death. We show that the DNA damage response (DDR) induced by ionizing radiation (IR) is coordinated in breast cancer cells by selective mRNA translation mediated by high levels of translation initiation factor eIF4G1. Increased expression of eIF4G1, common in breast cancers, was found to selectively increase translation of mRNAs involved in cell survival and the DDR, preventing autophagy and apoptosis (Survivin, HIF1, XIAP), promoting cell cycle arrest (GADD45a, p53, ATRIP, Chk1) and DNA repair (53BP1, BRCA1/2, PARP, Rfc2-5, ATM, MRE-11, others). Reduced expression of eIF4G1, but not its homolog eIF4G2, greatly sensitizes cells to DNA damage by IR, induces cell death by both apoptosis and autophagy, and significantly delays resolution of DNA damage foci with little reduction of overall protein synthesis. While some mRNAs selectively translated by higher levels of eIF4G1 were found to use internal ribosome entry site (IRES)-mediated alternate translation, most do not. The latter group shows significantly reduced dependence on eIF4E for translation, facilitated by an enhanced requirement for eIF4G1. Increased expression of eIF4G1 therefore promotes specialized translation of survival, growth arrest and DDR mRNAs that are important in cell survival and DNA repair following genotoxic DNA damage.
DNA damage and eIF4G1 in breast cancer cells reprogram translation for survival and DNA repair mRNAs.
Cell line
View SamplesTranscriptom analysis of microdissect adrenal medulla after 8 weeks of cardiac pressure overload caused by transverse aortic constriction.
Chronic cardiac pressure overload induces adrenal medulla hypertrophy and increased catecholamine synthesis.
Sex
View SamplesTranslation initiation factor eIF4E is overexpressed early in breast cancers in association with disease progression and reduced survival. Much remains to be understood regarding the role of eIF4E in human cancer. Using immortalized human breast epithelial cells, we report that elevated expression of elF4E translationally activates the TGF pathway, promoting cell invasion, loss of cell polarity, increased cell survival and other hallmarks of early neoplasia. Overexpression of eIF4E is shown to facilitate selective translation of integrin 1 mRNA, which drives the translationally controlled assembly of a TGF receptor signaling complex containing 31 integrins, -catenin, TGF receptor I, E-cadherin and phosphorylated Smads2/3. This receptor complex acutely sensitizes non-malignant breast epithelial cells to activation by typically sub-stimulatory levels of activated TGF. TGF can promote cellular differentiation or invasion and transformation. As a translational coactivator of TGF, eIF4E confers selective mRNA translation, reprogramming non-malignant cells to an invasive phenotype by reducing the set-point for stimulation by activated TGF. Overexpression of eIF4E may be a pro-invasive facilitator of TGF activity.
Eukaryotic Translation Initiation Factor 4E Is a Feed-Forward Translational Coactivator of Transforming Growth Factor β Early Protransforming Events in Breast Epithelial Cells.
Sex, Specimen part, Cell line
View Samples