We examined the transcriptional function of cyclin D1 in mouse development using two approaches. First, we queried association of cyclin D1 with the genome of E14.5 mouse embryos using ChIP-on-chip approach. We observed binding of cyclin D1 to several promoter regions. Second, we compared gene expression profiles between wild-type and cyclin D1-null retinas. We observed several transcripts with altered levels in cyclin D1-null organs.
Transcriptional role of cyclin D1 in development revealed by a genetic-proteomic screen.
No sample metadata fields
View SamplesCyclin C was cloned as a growth-promoting G1 cyclin, and was also shown to regulate gene transcription. Here we report that in vivo cyclin C acts as a haploinsufficient tumour suppressor, by controlling Notch1 oncogene levels. Cyclin C activates an 'orphan' CDK19 kinase, as well as CDK8 and CDK3. These cyclin-C-CDK complexes phosphorylate the Notch1 intracellular domain (ICN1) and promote ICN1 degradation. Genetic ablation of cyclin C blocks ICN1 phosphorylation in vivo, thereby elevating ICN1 levels in cyclin-C-knockout mice. Cyclin C ablation or heterozygosity collaborates with other oncogenic lesions and accelerates development of T-cell acute lymphoblastic leukaemia (T-ALL). Furthermore, the cyclin C encoding gene CCNC is heterozygously deleted in a significant fraction of human T-ALLs, and these tumours express reduced cyclin C levels. We also describe point mutations in human T-ALL that render cyclin-C-CDK unable to phosphorylate ICN1. Hence, tumour cells may develop different strategies to evade inhibition by cyclin C.
Cyclin C is a haploinsufficient tumour suppressor.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Characterization of a novel OTX2-driven stem cell program in Group 3 and Group 4 medulloblastoma.
Cell line
View SamplesMedulloblastoma (MB) is the most common malignant primary pediatric brain cancer. Among the most aggressive subtypes, Group 3 and Group 4 originate from stem/progenitor cells, frequently metastasize, and often display the worst prognosis, yet, as the names imply, we know the least about the molecular mechanisms driving their progression. Here, we show that the transcription factor orthodenticle homeobox 2 (OTX2) promotes self-renewal while inhibiting differentiation in vitro and increases tumor-initiating capacity from MB stem cell populations in vivo. Characterization of the OTX2 regulatory network revealed a novel relationship between OTX2 and genes associated with multiple axon guidance signaling pathways in Group 3 and Group 4 MB stem/progenitor cells. In particular, OTX2 levels were negatively correlated with semaphorin (SEMA) signaling, as expression of 9 SEMA pathway genes is upregulated following OTX2 knockdown with some being potential direct OTX2 targets. Importantly, this negative correlation between OTX2 and SEMA pathway genes was also observed in patient samples, with lower expression of SEMA4D associated with poor outcome in Group 3 and 4 tumors. Functional studies using established and newly derived MB cell lines demonstrated that increased levels of SEMA pathway genes are associated with decreased self-renewal and growth, and that RHO signaling, known to mediate the effects of SEMA genes, is contributing to the OTX2 KD phenotype. Our study provides critical mechanistic insight into the networks controlled by OTX2 in self-renewing MB cells and reveals novel roles for axon guidance genes and their downstream effectors as putative tumor suppressors and therapeutic targets in Group 3 and Group 4 MB.
Characterization of a novel OTX2-driven stem cell program in Group 3 and Group 4 medulloblastoma.
Cell line
View SamplesRats were given pulmonary embolism by i.v. injection of 25 micron polystyrene microspheres or 0.01% Tween20 solution as vehicle control
Differential effect of mild and severe pulmonary embolism on the rat lung transcriptome.
No sample metadata fields
View SamplesTime and dose related expression profiles of rat right heart tissue in microsphere bead model for Pulmonary embolism
Transcriptional profile of right ventricular tissue during acute pulmonary embolism in rats.
No sample metadata fields
View SamplesPulmonary vascular occlusions due to thromboemboli can result in pulmonary hypertension and right heart damage. Treatments to clear the vascular obstructions such as i.v. heparain or thrombolytics can resolve the hypertension but right ventricular damage often occurs first. Methods of protecting the right ventricle from hypertensive damage during the course of acute treatment to clear the thromboemboli are needed. Monocyte- and neutrophil-mediated inflammation and fibrosis are associated with chronic right ventricular damage but the pathways involved are not understood. A comprehesive survey of gene expression during chronic pulmonary embolism verses control rats has been conducted in this study.
Transcriptional changes in right ventricular tissues are enriched in the outflow tract compared with the apex during chronic pulmonary embolism in rats.
Sex
View SamplesThere are a few markers available to distinguish hepatic stellate cells (HSCs), portal fibroblasts (PFs), and mesothelial cells (MCs) in the adult mouse liver.
Characterization of hepatic stellate cells, portal fibroblasts, and mesothelial cells in normal and fibrotic livers.
Specimen part
View SamplesDazl (deleted in azoospermia like) is a member of the DAZ family of germ cell-restricted RNA binding proteins required for gametogenesis from worm to human. The direct RNA targets and functions of these essential proteins are poorly understood. Here, we generated high-resolution, transcriptome-wide maps of Dazl-RNA interactions in mouse testes. These maps provide important insights into the mechanism of Dazl recruitment to mRNA and reveal Dazl binding to thousands of mRNAs predominantly through sequence-specific interactions near the polyA tail. Using transgenic mice and fluorescence activated cell sorting (FACS), we isolated DAZL knockout germ cells and used RNA-Seq to identify mRNAs sensitive to DAZL-ablation. Intersecting the RNA-Seq and Dazl-RNA interaction datasets revealed that Dazl enhances expression of a subset of directly-bound transcripts, namely mRNAs for a network of essential cell cycle regulatory genes. Collectively, our integrative analysis delineates a Dazl-dependent post-transcriptional gene regulatory program essential for mammalian germ cell maintenance. Overall design: PolyA Seq libraries generated from isolated spermatogonial cells
DAZL Regulates Germ Cell Survival through a Network of PolyA-Proximal mRNA Interactions.
Sex, Specimen part, Cell line, Subject
View SamplesA persistent and non-resolving inflammatory response to accumulating A peptide species is a cardinal feature in the development of Alzheimer's disease (AD). In response to accumulating A peptide species, microglia, the innate immune cells of the brain, generate a toxic inflammatory response that accelerates synaptic and neuronal injury. Many pro-inflammatory signaling pathways are linked to progression of neurodegeneration. However, endogenous anti-inflammatory pathways capable of suppressing A-induced inflammation represent a relatively unexplored area.
Suppression of Alzheimer-associated inflammation by microglial prostaglandin-E2 EP4 receptor signaling.
Specimen part
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