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Homo sapiens
221 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In Huntingtons disease (HD), expanded HTT CAG repeat length correlates strongly with age at motor onset, indicating that it determines the rate of the disease process leading to diagnostic clinical manifestations. Similarly, in normal individuals, HTT CAG repeat length is correlated with biochemical differences that reveal it as a functional polymorphism. Here, we tested the hypothesis that gene expression signatures can capture continuous, length-dependent effects of the HTT CAG repeat. Using gene expression datasets for 107 HD and control lymphoblastoid cell lines, we constructed mathematical models in an iterative manner, based upon CAG correlated gene expression patterns in randomly chosen training samples, and tested their predictive power in test samples. Predicted CAG repeat lengths were significantly correlated with experimentally determined CAG repeat lengths, whereas models based upon randomly permuted CAGs were not at all predictive. Predictions from different batches of mRNA for the same cell lines were significantly correlated, implying that CAG length-correlated gene expression is reproducible. Notably, HTT expression was not itself correlated with HTT CAG repeat length. Taken together, these findings confirm the concept of a gene expression signature representing the continuous effect of HTT CAG length and not primarily dependent on the level of huntingtin expression. Such global and unbiased approaches, applied to additional cell types and tissues, may facilitate the discovery of therapies for HD by providing a comprehensive view of molecular changes triggered by HTT CAG repeat length for use in screening for and testing compounds that reverse effects of the HTT CAG expansion.
Publication Title
Dominant effects of the Huntington's disease HTT CAG repeat length are captured in gene-expression data sets by a continuous analysis mathematical modeling strategy.
Sample Metadata Fields
Sex
View Samples- Populus tremula x populus alba
- 18 Downloadable Samples
- Affymetrix Poplar Genome Array (poplar)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Expression profiling and functional analysis of Populus WRKY23 reveals a regulatory role in defense.
Sample Metadata Fields
Specimen part
View Samples- Populus tremula x populus alba
- 12 Downloadable Samples
- Affymetrix Poplar Genome Array (poplar)
Description
To investigate the function of poplar WRKY23, we generated PtWRKY23-overexpressing and -underexpressing (RNAi) plants. Transgenic plants were inoculated with Melampsora rust or mock-inoculated for assessment of rust-resistance and for gene expression profiling using the poplar Affymetrix GeneChip to study the consequences of PtWRKY23 overexpression and underexpression. Transcriptome analysis of PtWRKY23 overexpressors revealed a significant overlap with the Melampsora-infection response. Transcriptome analysis also indicated that PtWRKY23 affects redox homeostasis and cell wall-related metabolism.
Publication Title
Expression profiling and functional analysis of Populus WRKY23 reveals a regulatory role in defense.
Sample Metadata Fields
Specimen part
View Samples- Populus tremula x populus alba
- 6 Downloadable Samples
- Affymetrix Poplar Genome Array (poplar)
Description
To investigate the function of poplar WRKY23, we generated PtWRKY23-overexpressing and -underexpressing (RNAi) plants. Transgenic plants were inoculated with Melampsora rust or mock-inoculated for assessment of rust-resistance and for gene expression profiling using the poplar Affymetrix GeneChip to study the consequences of PtWRKY23 overexpression and underexpression. Transcriptome analysis of PtWRKY23 overexpressors revealed a significant overlap with the Melampsora-infection response. Transcriptome analysis also indicated that PtWRKY23 affects redox homeostasis and cell wall-related metabolism.
Publication Title
Expression profiling and functional analysis of Populus WRKY23 reveals a regulatory role in defense.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 17 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
In blood, the transcription factor C/EBPa is essential for myeloid differentiation and has been implicated in regulating self-renewal of fetal liver hematopoietic stem cells (HSCs). However, its function in adult HSCs is unknown. Here, using an inducible knockout model, we found that C/EBPa deficient adult HSCs underwent a pronounced expansion with enhanced proliferation, characteristics resembling fetal liver HSCs. Consistently, transcription profiling of C/EBPa deficient HSCs revealed a gene expression program similar to fetal liver HSCs. Moreover we observed that age-specific C/EBPa expression correlated with its inhibitory effect on the HSC cell cycle. Mechanistically, we identified N-Myc as a C/EBPa downstream target. C/EBPa upregulation during HSC transition from an active fetal state to a quiescent adult state was accompanied by down-regulation of N-Myc, and loss of C/EBPa resulted in de-repression of NMyc. Our data establish that C/EBPa acts as a molecular switch between fetal and adult states of HSC in part via transcriptional repression of the proto-oncogene N-Myc.
Publication Title
C/EBPa controls acquisition and maintenance of adult haematopoietic stem cell quiescence.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
It has long been known that leukemic cells disrupt normal patterns of blood cell formation, but little is understood about mechanisms. It has generally been assumed that normal hematopoietic stem and progenitor cells (HSPC) are simply out-competed for space by malignant cells. We designed a strategy to determine if leukemic cells alter intrinsic properties and functions of normal HSPCs. Chimeric mice were generated by transplantation of normal marrow and marrow from an inducible transgenic model of chronic myelogenous leukemia (CML). With induction of CML, the composition of the marrow changed dramatically, and normal HSPCs divided more readily and lost their ability to produce lymphocytes. In contrast, only modest changes were recorded in numbers of normal hematopoietic stem cells (HSCs). However, these stem cells were not unscathed, and had reduced reconstitution and self-renewal potential upon transplantation. Interestingly, the normal bystander cells acquired gene expression patterns resembling their neighboring malignant counterparts. This suggested that much of the leukemia signature is mediated by extrinsic factors in the environment.
Publication Title
Treatment of chronic myelogenous leukemia by blocking cytokine alterations found in normal stem and progenitor cells.
Sample Metadata Fields
Specimen part
View Samples
SRP090189- Mus musculus
- 1 Downloadable Sample
Illumina HiSeq 2000
Description
Background: In order to become functionally competent but harmless mediators of the immune system, T cells undergo a strict educational program in the thymus, where they learn to discriminate between self and non-self. This educational program is, to a large extent, mediated by medullary thymic epithelial cells (mTECs) that have a unique capacity to express, and subsequently present a large fraction of body antigens. While the scope of promiscuously expressed genes by mTECs is well established, relatively little is known about the expression of variants that are generated by co- and post-transcriptional processes. Results: Our study reveals that in comparison to other cell types, mTECs display significantly higher levels of alternative splicing, as well as A-to-I and C-to-U RNA editing, which thereby further expand the diversity of their self-antigen repertoire. Interestingly, Aire, the key mediator of mTECs promiscuous gene expression, plays a limited role in the regulation of these transcriptional processes. Conclusions: Our results highlight RNA processing as another layer by which the immune system assures a comprehensive self-representation in the thymus which is required for the establishment of self-tolerance and prevention of autoimmunity. Identification of the number of genes expressed in Aire-KO MEChi Overall design: ~100ng of total RNA was isolated by Trizol extraction from MHC-II high mTECs from a pool of 3 Aire-KO mice. Poly-A-selected transcriptome libraries were generated using the non-directionnal TruSeq V3 RNA Sample Prep Kit (without additional pre-amplification) following the manufacturer''s protocols. Enrichment of DNA fragment with adapter molecules on both ends was done using 15 cycles of PCR amplification using the Illumina PCR mix and primer cocktail. Paired-end (2 × 100 bp) sequencing was performed using the Illumina HiSeq2000 machine.
Publication Title
Extensive RNA editing and splicing increase immune self-representation diversity in medullary thymic epithelial cells.
Sample Metadata Fields
Specimen part, Subject
View Samples- Mus musculus
- 23 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Leukemia initiating cells (LICs) of acute myeloid leukemia (AML) may arise from self-renewing hematopoietic stem cells (HSCs) and from committed progenitors. However, it remains unclear how leukemia-associated oncogenes instruct LIC formation from cells of different origins and if differentiation along the normal hematopoietic hierarchy is involved. Here, using murine models with the driver mutations MLL-AF9 or MOZ-TIF2, we found that regardless of the transformed cell types, myelomonocytic differentiation to the granulocyte macrophage progenitor (GMP) stage is critical for LIC generation. Blocking myeloid differentiation through disrupting the lineage-restricted transcription factor C/EBPa eliminates GMPs, blocks normal granulopoiesis, and prevents AML development. In contrast, restoring myeloid differentiation through inflammatory cytokines rescues AML transformation. Our findings identify myeloid differentiation as a critical step in LIC formation and AML development, thus guiding new therapeutic approaches.
Publication Title
Hematopoietic Differentiation Is Required for Initiation of Acute Myeloid Leukemia.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 28 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Runx3-mediated transcriptional program in cytotoxic lymphocytes.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
NK cells are innate immune cells that recognize and kill foreign, virally-infected and tumor cells without the need for prior immunization. NK expansion following viral infection is IL-2 or IL-15-dependent.
Publication Title
Runx3-mediated transcriptional program in cytotoxic lymphocytes.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment
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