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GSE65577
Homo sapiens
4 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The role of infection in erythropoietic dysfunction is poorly understood. In children with P. falciparum malaria, the by-product of hemoglobin digestion in infected red cells (hemozoin) is associated with the severity of anemia which is independent of circulating levels of the inflammatory cytokine tumor necrosis alpha (TNF-alpha). To gain insight into the common and specific effects of TNF-alpha and hemozoin on erythropoiesis, we studied the gene expression profile of purified primary erythroid cultures exposed to either TNF-alpha (10ng/ml) or to hemozoin (12.5microgram/ml heme units) for 24 hours. Perturbed gene function was assessed using co-annotation of associated gene ontologies and expression of selected genes representative of the profile observed was confirmed by real time PCR (rtPCR). The changes in gene expression induced by each agent were largely distinct; many of the genes significantly modulated by TNF-alpha were not affected by hemozoin.
Publication Title
Distinct mechanisms of inadequate erythropoiesis induced by tumor necrosis factor alpha or malarial pigment.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 73 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
Erythropoiesis in mammals replenishes the circulating red blood cell (RBC) pool from hematopoietic stem/progenitor cells (HSPCs). Two distinct erythropoietic programs have been described. In the first trimester, hematopoietic precursors in the fetal yolk sac follow a primitive pattern of erythropoiesis. However, in the second trimester, hematopoietic stem cells (HSCs) from the fetal liver and later from the bone marrow differentiate by a definitive program of erythropoiesis to yield enucleated erythrocytes. RBCs can also be derived from human induced pluripotent stem cells (hiPSCs) and can express many of the red cell proteins required for normal erythrocyte function, presaging in vitro RBC production for clinical use. However, expansion and enucleation from hiPSCs is less efficient than with erythroblasts (EBs) derived from adult or cord blood progenitors. We hypothesized that substantial differential gene expression during erythroid development from hiPSCs compared to that from adult blood or cord blood precursors could account for these hitherto unexplained differences in proliferation and enucleation. We have therefore grown EBs from human adult and cord blood progenitors and from hiPSCs. Gene expression during erythroid culture from each erythroblast source was analyzed using algorithms designed to cluster co-expressed genes in an unsupervised manner and the function of differentially expressed genes explored by gene ontology. Using these methods we identify specific patterns of gene regulation for adult- and cord- derived EBs, regardless of the medium used, that are substantially distinct from those observed during the differentiation of EBs from hiPSC progenitors which largely follows a pattern of primitive erythropoiesis.
Publication Title
Distinct gene expression program dynamics during erythropoiesis from human induced pluripotent stem cells compared with adult and cord blood progenitors.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 13 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Understanding the pattern of gene expression and identifying the specific genes expressed during erythropoiesis is crucial for a synthesis of erythroid developmental biology. Here we have isolated four distinct populations of erythroblasts at successive erythropoietin-dependent stages of erythropoiesis including the terminal, pyknotic stage. The transcriptome has been determined using Affymetrix arrays. First, we show that cells sorted by surface expression profile express not only significantly fewer genes than unsorted cells, but also significantly more differences in the expression levels of particular genes between stages than unsorted cells, demonstrating the importance of working with defined cell populations to identify lineage and temporally-specific patterns of gene expression. Second, using standard software and matched filtering we identify eleven differentially regulated genes and one continuously expressed gene previously undetected in erythroid expression studies with unknown roles in erythropoiesis (CA3, CALB1, CTSL2, FKBP1B, GSDMB, ITLN1, LIN7B, RRAD, RUNDC3A, UNQ1887, ZNF805, MYL12B). Finally, using transcription factor binding site analysis we identify potential transcription factors that may regulate gene expression during terminal erythropoiesis. Our stringent lists of differentially regulated and continuously expressed transcripts are a resource for functional studies of erythropoietic protein function and gene regulation.
Publication Title
Global gene expression analysis of human erythroid progenitors.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 18 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Wnt signaling is intrinsic to mouse embryonic stem cell self-renewal. Therefore it is surprising that reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) is not strongly enhanced by Wnt signaling. Here, we demonstrate that active Wnt signaling inhibits the early stage of reprogramming to iPSCs, while it is required and even stimulating during the late stage. Mechanistically, this biphasic effect of Wnt signaling is accompanied by a change in the requirement of all four of its transcriptional effectors: Tcf1, Lef1, Tcf3, and Tcf4. For example, Tcf3 and Tcf4 are stimulatory early but inhibitory late in the reprogramming process. Accordingly, ectopic expression of Tcf3 early in reprogramming combined with its loss-of-function late enables efficient reprogramming in the absence of ectopic Sox2. Together, our data indicate that the step-wise process of reprogramming to iPSCs is critically dependent on the stage-specific control and action of all four Tcfs and Wnt signaling.
Publication Title
Stage-specific regulation of reprogramming to induced pluripotent stem cells by Wnt signaling and T cell factor proteins.
Sample Metadata Fields
Specimen part, Time
View Samples- Mus musculus
- 36 Downloadable Samples
- Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
Determination of gene expression changes in hindlimb muscle (gastrocnemius/soleus) of mdx (dystrophin-deficient) mice at postnatal ages 7, 14, 23, 28, 56, and 112.
Publication Title
Dissection of temporal gene expression signatures of affected and spared muscle groups in dystrophin-deficient (mdx) mice.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
Determination of gene expression changes in extraocular muscle of mdx (dystrophin-deficient) mice at postnatal ages 14, 28, 56, and 112 days. 3 independent replicates/age/strain.
Publication Title
Dissection of temporal gene expression signatures of affected and spared muscle groups in dystrophin-deficient (mdx) mice.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The observation that Tcf3 (MGI name: Tcf7l1) bound the same genes as core stem cell transcription factors, Oct4 (MGI name:Pou5f1), Sox2 and Nanog, revealed a potentially important aspect of the poorly understood mechanism whereby Wnts stimulate self renewal of pluripotent mouse embryonic stem (ES) cells. Although the conventional view of Tcf proteins as the -catenin-binding effectors of Wnt signaling suggested Tcf3 should activate target genes in response to Wnts, here we show that Wnt3a and Tcf3 effectively antagonize each others effects on gene expression. Genetic ablation of Tcf3 caused similar effects as treating cells with recombinant Wnt3a.
Publication Title
Opposing effects of Tcf3 and Tcf1 control Wnt stimulation of embryonic stem cell self-renewal.
Sample Metadata Fields
Treatment
View Samples- Homo sapiens
- 12 Downloadable Samples
IlluminaHiSeq2500
Description
Breast cancer is a major health problem affecting millions of women worldwide. Over 200,000 new cases are diagnosed annually in the USA, with approximately 40,000 of these cases resulting in death. HER2-positive (HER2+) breast tumors, representing 20–30 % of early-stage breast cancer diagnoses, are characterized by the amplification of the HER2 gene. However, the critical genes and pathways that become affected by HER2 amplification in humans are yet to be specifically identified. Furthermore, it is yet to be determined if HER2 amplification also affects the expression of long intervening non-coding (linc)RNAs, which are involved in the epigenetic regulation of gene expression. We examined changes in gene expression by next generation RNA sequencing in human tumors pre- and post- HER2 inhibition by trastuzumab in vivo, and changes in gene expression in response to HER2 knock down in cell culture models. We integrated our results with gene expression analysis of HER2+ tumors vs matched normal tissue from The Cancer Genome Atlas. The integrative analyses of these datasets led to the identification of a small set of mRNAs, and the associated biological pathways that become deregulated by HER2 amplification. Furthermore, our analyses identified three lincRNAs that become deregulated in response to HER2 amplification both in vitro and in vivo. Our results should provide the foundation for functional studies of these candidate mRNAs and lincRNAs to further our understanding of how HER2 amplification results in tumorigenesis. Also, the identified lincRNAs could potentially open the door for future RNA-based biomarkers and therapeutics in HER2+ breast cancer. Overall design: We compared changes in gene expression of both mRNAs and lincRNAs in BT474 cells that are treated with HER2 siRNAs vs cells treated with negative control siRNAs by RNA-seq.
Publication Title
Integrative transcriptome-wide analyses reveal critical HER2-regulated mRNAs and lincRNAs in HER2+ breast cancer.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 59 Downloadable Samples
Affymetrix Mouse Expression 430A Array (moe430a), Affymetrix Mouse Expression 430B Array (moe430b)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Distinctive morphological and gene/protein expression signatures during myogenesis in novel cell lines from extraocular and hindlimb muscle.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 36 Downloadable Samples
- Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
Determination of gene expression changes in extraocular muscle of mdx (dystrophin-deficient) mice at postnatal ages 7, 14, 23, 28, 56, and 112 days. 3 independent replicates/age/strain. Data form part of publication: Human Molecular Genetics 13:257-269, 2004.
Publication Title
Temporal gene expression profiling of dystrophin-deficient (mdx) mouse diaphragm identifies conserved and muscle group-specific mechanisms in the pathogenesis of muscular dystrophy.
Sample Metadata Fields
No sample metadata fields
View Samples