We are currently studying the mechanisms that confer tumour initiating potential upon SP, and as part of this work, we undertook gene profiling studies comparing expression between SP and non-SP cells, initially focusing on the most common soft tissue sarcoma, malignant fibrous histiocytoma (or MFH)
Hedgehog and Notch signaling regulate self-renewal of undifferentiated pleomorphic sarcomas.
No sample metadata fields
View SamplesTumours contain heterogeneous cell populations. A population enriched in tumour-initiating potential has been identified in soft-tissue sarcoma (STS) by the isolation of side population (SP) cells. In this study, we compared the gene expression profiles of SP and non-SP cells in STS and identified Hedgehog (Hh) and Notch pathways as potential candidates for the targeting of SP cells. Upon verification of the activation of these pathways in SP cells, using primary tumor xenografts in NOD-SCID mice as our experimental model, we used the Hh blocker Triparanol and the Notch blocker DAPT to demonstrate that the suppression of these pathways effectively depleted the abundance of SP cells, reduced tumour growth, and inhibited the tumour-initiating potential of the treated sarcoma cells upon secondary transplantation. The data provide additional evidence that SP cells act as tumour initiating cells and points to Hh and Notch pathways as enticing targets for developing potential cancer therapies.
Hedgehog and Notch signaling regulate self-renewal of undifferentiated pleomorphic sarcomas.
Specimen part
View SamplesProtein-RNA interactions are integral components of nearly every aspect of biology including regulation of gene expression, assembly of cellular architectures, and pathogenesis of human diseases. However, studies in the past few decades have only uncovered a small fraction of the vast landscape of the protein-RNA interactome in any organism, and even less is known about the dynamics of protein-RNA interactions under changing developmental and environmental conditions. Here, we describe the gPAR-CLIP (global photoactivatable-ribonucleoside-enhanced crosslinking and immunopurification) approach for capturing regions of the transcriptome bound by RNA-binding proteins (RBPs) in budding yeast. We report over 13,000 RBP crosslinking sites in untranslated regions (UTR) covering 72% of protein-coding transcripts encoded in the genome, confirming 3' UTRs as major sites for RBP interaction. Comparative genomic analyses reveal that RBP crosslinking sites are highly conserved, and RNA folding predictions indicate that secondary structural elements are constrained by protein binding and may serve as generalizable modes of RNA recognition. Finally, 38% of 3' UTR crosslinking sites show changes in RBP occupancy upon glucose or nitrogen deprivation, with major impacts on metabolic pathways as well as mitochondrial and ribosomal gene expression. Our study offers an unprecedented view of the pervasiveness and dynamics of protein-RNA interactions in vivo. Overall design: Duplicate gPAR-CLIP and mRNA-seq libraries were sequenced from yeast strains for each of three conditions: log-phase growth, growth after 2 hour glucose starvation, and growth after 2 hour nitrogen starvation. Additional duplicate mRNA-seq libraries were sequenced from yeast strains grown in the absence of 4-thiouracil. gPAR-CLIP libraries were used to determine regions of mRNA bound by proteins. mRNA-seq libraries served as controls for mRNA abundance. A Puf3p PAR-CLIP library was sequenced to determine how well gPAR-CLIP captured the binding signatures of a single RNA-binding protein.
RNA promotes phase separation of glycolysis enzymes into yeast G bodies in hypoxia.
Cell line, Treatment, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Primate-specific endogenous retrovirus-driven transcription defines naive-like stem cells.
Sex, Specimen part, Cell line
View SamplesWe surveyed RNA-Seq data to identify those TEs that are transcriptionally active uniquely in human pluripotent cells. We identified one endogenous retrovirus (HERV-H) family, uniquely found in primates as being unusually abundant in the transcriptome. The microarray data provided is to support our human naive cell hypothesis.
Primate-specific endogenous retrovirus-driven transcription defines naive-like stem cells.
Sex, Cell line
View SamplesGenome-wide alternative splice analysis of RNA from lupus and its severe form lupus nephritis
Genome-wide peripheral blood transcriptome analysis of Arab female lupus and lupus nephritis.
Sex, Specimen part, Disease stage
View SamplesThe growth factor interleukin-3 (IL-3) promotes the survival and growth of multipotent hematopoietic progenitors and stimulates myelopoiesis. It has also been reported to oppose terminal granulopoiesis and to support leukemic cell growth through autocrine or paracrine mechanisms. We used kinetic microarray, Northern Blotting and bioinformatics analysis of IL-3 dependent myeloblasts to determine whether IL-3 acts in part by regulating the rate of turnover of mRNA transcripts in specific functional pathways. Our results indicate that exposure of myeloblasts to IL-3 causes immediate early stabilization of hundreds of transcripts in pathways relevant to myeloblast function. Examples include transcripts associated with proliferation and leukemic transformation (pik3cd, myb, pim-1), hematopoietic development (cited2), differentiation control (cdkn1a) and RNA processing (BRF1, BRF2). A domain in the 3-utr of IL-6 that mediates IL-3 responsiveness contains AU-rich elements that bind proteins known to modulate mRNA stability, however a known destabilizing protein (AUF1) is shown not to mediate degradation in the absence of IL-3. These findings support a model of IL-3 action through mRNA stability control and suggest that aberrant stabilization of this network of transcripts could contribute to growth patterns observed in leukemia.
IL-3 and oncogenic Abl regulate the myeloblast transcriptome by altering mRNA stability.
No sample metadata fields
View SamplesHuman erythroblasts purified from cord blood were cultured in vitro and FACS-sorted into five highly purified populations representing distinct differentiation stages: proerythroblasts, early basophilic erythroblasts, late basophilic erythroblasts, polychromatophilic erythroblasts, and orthochromatophilic erythroblasts. The methods for culture and sorting experiments are given in Hu et al. 2013. For each RNA-seq library, RNA was isolated from 1x 106 sorted human erythroblasts using RNeasy Plus Mini kits (Qiagen). Libraries were then prepared using Illumina TruSeqTM RNA kits to obtain 50 nt reads. Collaborators at the New Your Blood Center were responsible for erythroblast culture, FACS purification of erythroblast populations, and acquisition of RNA-seq data. Collaborators at U.C. Berkeley and Lawrence Berkeley National Laboratory performed data analysis and experimental validation of alternative splicing in erythroblasts. Results: Differentiating erythroblasts execute a dynamic alternative splicing program that is enriched in genes affecting cell cycle, organelle organization, chromatin function, and RNA processing. Alternative splicing plays a major role in regulating gene expression to ensure synthesis of appropriate proteome at each stage as the cells remodel in preparation for production of mature red cells. Overall design: Erythroid differentiation stage-specific transcriptome analysis was performed by RNA-seq analysis of highly purified erythroblast populations
A dynamic alternative splicing program regulates gene expression during terminal erythropoiesis.
No sample metadata fields
View SamplesFat intake is an important determinant in the development of obesity. The small intestine is the principal site of digestion and absorption of nutrients, and these short-term circulating nutrients and hormones as well as neural signals derived from the peripheral tissues in responses to a meal act at multiple central nervous system sites where food intake is controlled.
Identification of the principal transcriptional regulators for low-fat and high-fat meal responsive genes in small intestine.
Sex, Specimen part
View SamplesUsing RNA-Seq, we compared the transcriptomes of muscle from wild type C57BL/6J or Zp407 transgenic mice. Overall design: Biceps femoris were stored in RNAlater from 5-week-old overnight-fasted male mice. 5 mice were used per group for wild type and Zp407 transgenic mice.
Zinc finger protein 407 overexpression upregulates PPAR target gene expression and improves glucose homeostasis in mice.
Sex, Age, Specimen part, Subject
View Samples