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Homo sapiens
29 Downloadable Samples
Affymetrix Human Genome U133A Array (hgu133a)
Description
Epigenetic mechanisms contribute to deregulated gene expression of hematopoietic progenitors in Myelodysplastic Syndromes (MDS). Hypomethylating agents are able to improve peripheral cytopenias in MDS patients. To identify critical gene expression changes induced by hypomethylating agents, we analyzed gene expression profiling (GEP) of myelodysplastic and normal CD34+ hematopoietic stem cells treated in vitro with or without decitabine. Four MDS and two untreated early stage Hodgkins lymphomas were analyzed for GEP. Mock treated CD34+ stem cells segregate according to diagnosis and karyotype. After decitabine treatment, gene expression changes were more consistent on MDS CD34+ cells with abnormal kayotype. Comparing decitabine-induced genes with those found down-regulated in mock-treated MDS cells, we identified a list of candidate tumor suppressor genes in MDS. By real-time RT-PCR we confirmed expression changes for three selected genes CD9, CXCR4 and GATA2 in 12 MDS patients and 4 controls. CD9 was widely repressed in most MDS CD34+ cell samples, although similar levels of methylation were found in both normal and MDS total bone marrows. CXCR4 promoter methylation was absent in total bone marrows from 36 MDS patients. In conclusion, changes in gene expression changes induced by hypomethylating treatment are more pronounced in CD34+ cells from abnormal karyotype.
Publication Title
Gene expression profiling of myelodysplastic CD34+ hematopoietic stem cells treated in vitro with decitabine.
Sample Metadata Fields
Sex, Age, Specimen part, Disease
View Samples- Drosophila melanogaster
- 2 Downloadable Samples
Illumina Genome Analyzer II
Description
Adult stem cells support tissue homeostasis and repair throughout the life of an individual. However, numerous intrinsic and extrinsic changes occur with age that result in altered stem cell behavior and reduced tissue maintenance and regeneration. In the Drosophila testis, stem cells surround and contact the apical hub, a cluster of somatic cells that express the self-renewal factor Unpaired (Upd), which activates the JAK-STAT pathway in adjacent stem cells. However, aging results in a dramatic decrease in upd expression, with a concomitant loss of germline stem cells (GSCs). Here we present genetic and biochemical data to demonstrate that IGF-II mRNA binding protein (Imp) counteracts endogenous small interfering RNAs to stabilize upd RNA and contribute to maintenance of the niche. However, Imp expression decreases in hub cells of older males, similar to upd, which is due to targeting of Imp by the heterochronic microRNA let-7. Therefore, in the absence of Imp, upd mRNA becomes unprotected and susceptible to degradation. Understanding the mechanistic basis for aging-related changes in stem cell behavior will lead to the development of strategies to treat age-onset diseases and facilitate stem cell based therapies in older individuals. Overall design: Examination of small RNA levels in testes from young (1day old) and aged (30days old) males of Drosophila melanogaster by deep sequencing (using Illumina GAII).
Publication Title
The let-7-Imp axis regulates ageing of the Drosophila testis stem-cell niche.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 8 Downloadable Samples
- IlluminaHiSeq2000
Description
Notch activation is instrumental in the development of most T-cell acute lymphoblastic leukemia (T-ALL) cases, yet Notch mutations alone are not sufficient to recapitulate the full human disease in animal models. We here found that Notch1 activation at the fetal liver (FL) stage expanded the hematopoietic progenitor population and conferred it transplantable leukemic-initiating capacity. However, leukemogenesis and leukemic-initiating cell capacity induced by Notch1 was critically dependent on the levels of ß-Catenin in both FL and adult bone marrow contexts. In addition, inhibition of ß-Catenin compromised survival and proliferation of human T-ALL cell lines carrying activated Notch1. By transcriptome analyses, we identified the MYC pathway as a crucial element downstream of ß-Catenin in these T-ALL cells and demonstrate that the MYC 3'' enhancer required ß-Catenin and Notch1 recruitment to induce transcription. Finally, PKF115-584 treatment prevented and partially reverted leukemogenesis induced by active Notch1. Overall design: Four T-ALL cell lines (RPMI8402, HPB-ALL, Jurkat, CCRF-CEM) were treated with DMSO (control) or PKF115-584 (310nM) for 3hrs. Gene expression changes were measured with Cufflinks comparing the 4 control with the 4 treated samples.
Publication Title
β-Catenin is required for T-cell leukemia initiation and MYC transcription downstream of Notch1.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
DNMT1-interacting RNAs block gene-specific DNA methylation.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
We used the microarray analysis to detail the gene expression profile from the leukemic cell line HL-60
Publication Title
DNMT1-interacting RNAs block gene-specific DNA methylation.
Sample Metadata Fields
Cell line
View Samples
SRP009094- Homo sapiens
- 2 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
Identification of the all RNA species associated with DNMT1. Using a comparative genome-scale approach we identified and correlated the RNA species physically associated with DNMT1 and proximal to the annotated genes to the methylation status of the corresponding loci and expression levels of the respective genes. This comparative approach delineated the first -DNMT1 centered- 'epitranscriptome' map, a comprehensive map cross-referencing DNMT1-interacting transcripts to (i) DNA methylation and (ii) gene expression profile. Overall design: Relationship between DNMT1-RNA interactions, DNA methylation and gene expression
Publication Title
DNMT1-interacting RNAs block gene-specific DNA methylation.
Sample Metadata Fields
Cell line, Subject
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Ten-eleven translocation (Tet) family of DNA dioxygenases converts 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5- carboxylcytosine (5caC) through iterative oxidation reactions. While 5mC and 5hmC are relatively abundant, 5fC and 5caC are at very low levels in the mammalian genome. Thymine DNA glycosylase (TDG) and base excision repair (BER) pathways can actively remove 5fC/5caC to regenerate unmethylated cytosine, but it is unclear to what extent and at which part of the genome such active demethylation processes take place. Here, we have performed high-throughput sequencing analysis of 5mC/5hmC/5fC/5caC- enriched DNA using modification-specific antibodies and generated genome-wide distribution maps of these cytosine modifications in wild-type and Tdg-deficient mouse embryonic stem cells (ESCs). We observe that the steady state 5fC and 5caC are preferentially detected at repetitive sequences in wild-type mouse ESCs. Depletion of TDG causes marked accumulation of 5fC and 5caC at a large number of distal gene regulatory elements and transcriptionally repressed/poised gene promoters, suggesting that Tet/TDG-dependent dynamic cycling of 5mC oxidation states may be involved in regulating the function of these regions. Thus, comprehensive mapping of 5mC oxidation and BER pathway activity in the mammalian genome provides a promising approach for better understanding of biological roles of DNA methylation and demethylation dynamics in development and diseases.
Publication Title
Genome-wide analysis reveals TET- and TDG-dependent 5-methylcytosine oxidation dynamics.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The NOD (nonobese diabetic) mouse strain develops a characteristic autoimmune syndrome that closely resembles human type I diabetes. It has been suggested that NOD mice exhibit both numerical deficiency in CD4+CD25+ regulatory T cells (Treg) and reduced suppressive activity. We compared sorted CD4+CD25+ Tregs from the spleens of 6-7 week-old female NOD and nondiabetic B6.H2g7 mice. Tregs were 932% and 951% Foxp3+ in NOD and B6.H2g7 cells, respectively, on post-sort reanalysis. "Conventional" CD4+CD25- T cells (Tconv) are included as reference populations. Surprisingly, Treg "signature" is similar between the two strains, with only a few probesets that subtly deviate.
Publication Title
The defect in T-cell regulation in NOD mice is an effect on the T-cell effectors.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Hematopoietic Stem Cells (HSC) are originated during embryonic development from endothelial-like cells located in the ventral side of the dorsal aorta around day E10-12 of murine development. This region is called AGM for Aorta/Gonad/Mesonephros and refers to the tissues around the hemogenic aorta. Cells that emerge from the endothelium and show hematopoietic traits can be distinguished by the expression of the c-kit receptor and finally acquire the CD45 marker.
Publication Title
Hematopoietic stem cell development requires transient Wnt/β-catenin activity.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Ten-eleven translocation (Tet) family of DNA dioxygenases converts 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5- carboxylcytosine (5caC) through iterative oxidation reactions. While 5mC and 5hmC are relatively abundant, 5fC and 5caC are at very low levels in the mammalian genome. Thymine DNA glycosylase (TDG) and base excision repair (BER) pathways can actively remove 5fC/5caC to regenerate unmethylated cytosine, but it is unclear to what extent and at which part of the genome such active demethylation processes take place. Here, we have performed high-throughput sequencing analysis of 5mC/5hmC/5fC/5caC- enriched DNA using modification-specific antibodies and generated genome-wide distribution maps of these cytosine modifications in wild-type and Tdg-deficient mouse embryonic stem cells (ESCs). We observe that the steady state 5fC and 5caC are preferentially detected at repetitive sequences in wild-type mouse ESCs. Depletion of TDG causes marked accumulation of 5fC and 5caC at a large number of distal gene regulatory elements and transcriptionally repressed/poised gene promoters, suggesting that Tet/TDG-dependent dynamic cycling of 5mC oxidation states may be involved in regulating the function of these regions. Thus, comprehensive mapping of 5mC oxidation and BER pathway activity in the mammalian genome provides a promising approach for better understanding of biological roles of DNA methylation and demethylation dynamics in development and diseases.
Publication Title
Genome-wide analysis reveals TET- and TDG-dependent 5-methylcytosine oxidation dynamics.
Sample Metadata Fields
Specimen part
View Samples