Gene expression studies from hematopoietic stem cell (HSC) populations purified to variable degrees have defined a set of stemness genes. The present study describes the construction and comparative molecular analysis of l-phage cDNA libraries from highly purified primitive HSCs (PHSCs) which retained their long term repopulating activities (LTRAs), and from maturing HSCs (MHSCs) which were largely depleted of LTRAs. Library inserts were amplified and tagged by a T7 RNA polymerase promoter and used to generate biotinylated cRNA for Microarray hybridization. Microarray analysis of the libraries confirmed previous results but also revealed an unforseen preferential expression of translation and metabolism associated genes in the PHSCs. Therefore these data indicate that HSCs are quiescent only in regard of proliferative activities, but are in a state of readiness to provide the metabolic and translational activities required following induction of proliferation by factors which induce differentiation and exit from the HSC pool.
Gene expression profiles in murine hematopoietic stem cells revisited: analysis of cDNA libraries reveals high levels of translational and metabolic activities.
No sample metadata fields
View SamplesAn increasingly common method for predicting gene activity is genome-wide chromatin immunoprecipitation of ‘active’ chromatin modifications followed by massively parallel sequencing (ChIP-seq). Using a novel ChIP-seq quantification method (cRPKM), we tested the power of such ChIP-seq strategies to predict relative protein and RNA levels at the pre-pro-B and pro-B differentiation stages in early B cell lymphopoiesis. Using a multi-omics approach that compares promoter chromatin status (ChIP-seq; published in GSE:21978) with ongoing active transcription (GRO-seq; published in GSE:40173), steady state mRNA (RNA-seq), inferred mRNA stability, and relative proteome abundance measurements (iTRAQ), we demonstrate that active chromatin modifications at promoters are a good indicator of transcription and steady state mRNA levels. Moreover, we found that promoters with active chromatin modifications exclusively in one of these cell states frequently predicted differentially expressed proteins. However, we found that many genes whose promoters have non-differential but active chromatin modifications also displayed changes in expression of their cognate proteins. This large class of developmentally and differentially regulated proteins that was uncoupled from chromatin status used mostly post-transcriptional mechanisms. Interestingly, the most differentially expressed protein in our B-cell development system, 2410004B18Rik, was regulated by a post-transcriptional mechanism, which further analyses indicated was mediated by an identified miRNA. These data provide a striking example of how our integrated multi-omics data set can be useful in uncovering regulatory mechanisms. Overall design: Total RNA from mouse pre-pro-B and pro-B cells, depleted of rRNA and small RNAs, was sequenced using a strand specific, single end sequencing strategy.
Prediction of Gene Activity in Early B Cell Development Based on an Integrative Multi-Omics Analysis.
No sample metadata fields
View SamplesAdipocytes arise from commitment and differentiation of adipose precursors in white adipose tissue (WAT). In studying adipogenesis, precursor markers, including Pref-1 and PDGFRa, are used to isolate precursors from stromal vascular fraction of WAT, but the relationship among the markers is not known. Here, we used Pref-1 promoter-rtTA system in mice for labeling Pref-1+ cells and for inducible inactivation of Pref-1 target, Sox9. We show requirement of Sox9 for maintenance of Pref-1+ proliferative, early precursors. Upon Sox9 inactivation, these Pref-1+ cells become PDGFRa+ cells that express early adipogenic markers. Thus, we show for the first time that Pref-1+ cells precede PDGFRa+ cells in the adipogenic pathway and that Sox9 inactivation is required for WAT growth and expansion. Furthermore, we show that, in maintaining early adipose precursors, Sox9 activates Meis1 which prevents adipogenic differentiation. Our study also demonstrates the Pref-1 promoter-rtTA system for inducible gene inactivation in early adipose precursor population. Overall design: RNA-Sequencing for differentially expressed genes (more than 2-fold) between GFP+ (Pref-1+) ingWAT SVF cells from floxed and Sox9 PreASKO mice (n=6 pooled).
Sox9-Meis1 Inactivation Is Required for Adipogenesis, Advancing Pref-1<sup>+</sup> to PDGFRα<sup>+</sup> Cells.
Sex, Age, Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Sox9-Meis1 Inactivation Is Required for Adipogenesis, Advancing Pref-1<sup>+</sup> to PDGFRα<sup>+</sup> Cells.
Sex, Age, Specimen part, Cell line
View SamplesReprogramming of somatic cells produces induced pluripotent stem cells (iPSCs) that are invaluable resources for biomedical research. Transcriptional and epigenetic changes have been investigated to facilitate our understanding of the reprogramming process. Here, we extended the previous transcriptome studies by performing RNA-seq on cells defined by a combination of multiple cellular surface markers. We found that transcriptome changes during early reprogramming occur independently from the opening of closed chromatin by OCT4, SOX2, KLF4 and MYC (OSKM). Furthermore, our data identify multiple spliced forms of genes uniquely expressed at each progressive stage of reprogramming. In particular, we found a pluripotency-specific spliced form of CCNE1 that significantly enhances reprogramming. In addition, single nucleotide polymorphism (SNP) expression analysis reveals that monoallelic gene expression is induced in the intermediate stages of reprogramming while biallelic expression is recovered upon completion of reprogramming. Our transcriptome data provide unique opportunities in understanding human iPSC reprogramming. Overall design: RNA samples from intermediates of hiPSC reprogramming were obtained. Gene expression of those cells were analyzed.
Transcriptome Signature and Regulation in Human Somatic Cell Reprogramming.
No sample metadata fields
View SamplesReprogramming somatic cells to induced pluripotency by Yamanaka factors is usually slow and inefficient, and is thought to be a stochastic process. We identified a privileged somatic cell state, from which acquisition of pluripotency could occur in a non-stochastic manner. Subsets of murine hematopoietic progenitors are privileged, whose progeny cells predominantly adopt the pluripotent fate with activation of endogenous Oct4 locus after 4-5 divisions in reprogramming conditions. Privileged cells display an ultrafast cell cycle of ~8 hours. In fibroblasts, a subpopulation cycling at a similar ultrafast speed is observed after 6 days of factor expression, and is increased by p53-knockdown. This ultrafast-cycling population accounts for >99% of the bulk reprogramming activity in wildtype or p53-knockdown fibroblasts. We compared the transcriptomes of the fast cycling cells with those of slower hematopoietic progenitors, bulk fibroblasts and established iPS cells. Overall design: 3-5 replicates for each of the six cell types were included: 4 replicates for established iPS cells, 4 replicates for bulk mouse embryonic fibroblasts (MEF), 4 replicates for fast cycling MEF, 4 replicates for slow cycling MEF, 5 replicates for fast cycling granulocyte monocyte progenitors (GMP) and 3 replicates for slow cycling GMP.
Nonstochastic reprogramming from a privileged somatic cell state.
No sample metadata fields
View SamplesThe intention was to detect genes that are determining trastuzumab efficiency in HER2-positive breast cancer cell lines with different resistance phenotypes. While BT474 should be sensitive to the drug treatment, HCC1954 is expected to be resistant due to a PI3K mutation. The cell line BTR50 has been derived from BT474 and was cultured to be resistant as well. Based on RNA-Seq data, we performed differential expression analyses on these breast cancer cell lines with and without trastuzumab treatment. In detail, five separate tests were performed, namely resistant cells vs. wild type, i.e. HCC1954 and BTR50 vs. BT474, respectively, and untreated vs. drug treated cells. The significant genes of the first two tests should contribute to resistance. The significant genes of the test BT474 vs. its drug treated version should contribute to the trastuzumab effect. To exclude false positives from the combined gene set (#64), we removed ten genes that were also significant in the test BTR50 vs. its drug treated version. This way we ended up with 54 genes that are very likely to determine trastuzumab efficiency in HER2-positive breast cancer cell lines. Overall design: mRNA profiles of human breast cancer cell lines were generated by deep sequencing using Illumina HiSeq 2000. The cell lines BT474 and HCC1954 were analyzed with and without trastuzumab treatment. HCC1954 is known to be trastuzumab resistant. Additionally, the cell line BTR50 was generated as resistant version of BT474, and was analyzed with and without trastuzumab as well.
mRNA profiling reveals determinants of trastuzumab efficiency in HER2-positive breast cancer.
No sample metadata fields
View SamplesThe pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) and its relationship to other lymphomas are largely unknown. This is partly due to the technical challenge of analyzing its rare neoplastic L&H cells, which are dispersed in an abundant non-neoplastic cellular microenvironment. We performed a genome-wide expression study of microdissected lymphocytic and histiocytic (L&H) lymphoma cells in comparison to normal and other malignant B cells, which indicates a relationship of L&H cells to and/or origin from germinal center B cells at transition to memory B cells. L&H cells show a surprisingly high similarity to the tumor cells of T cell-rich B cell lymphoma and classical Hodgkin lymphoma, a partial loss of their B cell phenotype and deregulation of many apoptosis-regulators and putative oncogenes. Importantly, L&H cells are characterized by constitutive NF-B activity and aberrant ERK signaling. Thus, these findings shed new light on the nature of L&H cells, revealed several novel pathogenetic mechanisms in NLPHL, and may help in differential diagnosis and lead to novel therapeutic strategies.
Origin and pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma as revealed by global gene expression analysis.
No sample metadata fields
View SamplesThe objective is to relate changes in expression of DOR/TRP53INP2, a factor involved in thyroid hormone action and autophagy, to body composition in mice fed a fat (FD) or high fat diet (HFD) for 8 days and in a genetically obese mouse model.
Extrinsic and intrinsic regulation of DOR/TP53INP2 expression in mice: effects of dietary fat content, tissue type and sex in adipose and muscle tissues.
Sex, Age, Specimen part
View SamplesCdc34 is an essential E2 ubiquitin conjugating enzyme found in nearly all eukaryotes. It contains a highly conserved motif composed of S73/S97/12 amino acid insert near the active site cysteine. This motif is unique to Cdc34/Ubc7 type E2s while other E2s contain K/D/no insert at these positions. To better understand the function of this motif we mutated Cdc34 S73/S97/insert to be K/D/no insert and observed changes in transcript levels in mid-log phase yeast cells. ABSTRACT [Cdc34 is a ubiquitin conjugating enzyme necessary for the ubiquitylation of substrates by the SCF family of ubiquitin ligases. Previous work has shown that the Cdc34 protein is phosphorylated in vivo on serine residues. Cdc34 contains two serines within its catalytic domain, S73 and S97, that together with a 12 amino acid acidic loop, constitute a highly conserved motif (serine, serine, insert) among all members of the Cdc34 family of E2 enzymes. Using phosphospecific antibodies, we show that the essential serine S97 is indeed phosphorylated in vivo. Furthermore, this phosphorylation event is regulated by treatment with pheromone in yeast. Consistently, expression of a Cdc34 mutant lacking this motif (serine, serine, insert) leads to misregulation of the SCF substrates, Sic1, Far1, Cln1 and Cln2 and suppresses the cell cycle arrest brought about by an activated mating pathway. We further explored the function of this motif by microarray analysis and show that the transcripts of nearly the entire Sic1 cluster of co-transcribed genes is altered in a strain the expresses Cdc34 lacking this motif. Our data reveals that this highly conserved motif in Cdc34 and its phosphorylation are important for modulating SCF substrate abundance both transcriptionally and post-transcriptionally.]
New insight into the role of the Cdc34 ubiquitin-conjugating enzyme in cell cycle regulation via Ace2 and Sic1.
No sample metadata fields
View Samples