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GSE70739
Homo sapiens
24 Downloadable Samples
Illumina HumanHT-12 V4.0 expression beadchip
Description
The pluripotency of newly developed human induced pluripotent stem cells (iPSCs) is usually characterized by physiological parameters; i.e., by their ability to maintain the undifferentiated state and to differentiate into derivatives of the three germ layers. Nevertheless, a molecular comparison of physiologically normal iPSCs to the gold standard of pluripotency, embryonic stem cells (ESCs), often reveals a set of genes with different expression and/or methylation patterns in iPSCs and ESCs. To evaluate the contribution of the reprogramming process, parental cell type, and fortuity in the signature of human iPSCs, we developed a complete isogenic reprogramming system. We performed a genome-wide comparison of the transcriptome and the methylome of human isogenic ESCs, three types of ESC-derived somatic cells (fibroblasts, retinal pigment epithelium and neural cells), and three pairs of iPSC lines derived from these somatic cells. Our analysis revealed a high input of stochasticity in the iPSC signature that does not retain specific traces of the parental cell type and reprogramming process. We showed that five iPSC clones are sufficient to find with 95% confidence at least one iPSC clone indistinguishable from their hypothetical isogenic ESC line. Additionally, on the basis of a small set of genes that are characteristic of all iPSC lines and isogenic ESCs, we formulated an approach of the best iPSC line selection and confirmed it on an independent dataset.
Publication Title
No associated publication
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 24 Downloadable Samples
- Illumina HumanHT-12 V4.0 expression beadchip
Description
The pluripotency of newly developed human induced pluripotent stem cells (iPSCs) is usually characterized by physiological parameters; i.e., by their ability to maintain the undifferentiated state and to differentiate into derivatives of the three germ layers. Nevertheless, a molecular comparison of physiologically normal iPSCs to the gold standard of pluripotency, embryonic stem cells (ESCs), often reveals a set of genes with different expression and/or methylation patterns in iPSCs and ESCs. To evaluate the contribution of the reprogramming process, parental cell type, and fortuity in the signature of human iPSCs, we developed a complete isogenic reprogramming system. We performed a genome-wide comparison of the transcriptome and the methylome of human isogenic ESCs, three types of ESC-derived somatic cells (fibroblasts, retinal pigment epithelium and neural cells), and three pairs of iPSC lines derived from these somatic cells. Our analysis revealed a high input of stochasticity in the iPSC signature that does not retain specific traces of the parental cell type and reprogramming process. We showed that five iPSC clones are sufficient to find with 95% confidence at least one iPSC clone indistinguishable from their hypothetical isogenic ESC line. Additionally, on the basis of a small set of genes that are characteristic of all iPSC lines and isogenic ESCs, we formulated an approach of the best iPSC line selection and confirmed it on an independent dataset.
Publication Title
No associated publication
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 12 Downloadable Samples
- Illumina HumanHT-12 V4.0 expression beadchip
Description
Huntingtons disease (HD) is an incurable hereditary neurodegenerative disorder, which manifests itself as a loss of GABAergic medium spiny (GABA MS) neurons in the striatum and caused by an expansion of the CAG repeat in exon 1 of the huntingtin gene. There is no cure for HD, existing pharmaceutical can only relieve its symptoms. Here, induced pluripotent stem cells were established from patients with low CAG repeat expansion in the huntingtin gene, and were then efficiently differentiated into GABA MS-like neurons under defined culture conditions. Analysis of differentially expressed genes between Huntingtons disease and wild type iPSCs derived GABA MS-like neurons has been performed.
Publication Title
Manifestation of Huntington's disease pathology in human induced pluripotent stem cell-derived neurons.
Sample Metadata Fields
Age, Specimen part
View Samples- Gallus gallus
- 6 Downloadable Samples
- Affymetrix Chicken Genome Array (chicken)
Description
Fibrotic diseases are a group of pathologies with high incidence and mortality. Despite extensive research efforts, efficient therapies are still not available. Understanding the molecular mechanisms driving the onset, progression and possible resolution of fibrosis is a prerequisite to the development of successful therapies. The central role of the TGF-beta pathway and myofibroblasts in the pathogenesis of fibrosis is now generally accepted. The possible mechanisms of myofibroblast elimination or dedifferentiation, on the other hand, are still almost uncharted territory. Basic fibroblast growth factor (bFGF) is able to suppress myofibroblastic differentiation of mesenchymal cells, but the underlying mechanism has not been studied in detail. Here, we show that sustained expression of the transcription factor EGR4, which is inducible by bFGF, in primary chicken embryo dermal myofibroblasts results in suppression of the myofibroblastic phenotype, characterized by the loss of smooth muscle actin fibers and a substantial reduction in the production of extracellular matrix. Detailed analysis of the possible molecular mechanisms revealed FOXG1, BAMBI, NAB1, NAB2 and DUSP5 genes forming an EGR4 regulated network counteracting autocrine TGF-beta signaling.
Publication Title
Effective myofibroblast dedifferentiation by concomitant inhibition of TGF-β signaling and perturbation of MAPK signaling.
Sample Metadata Fields
Specimen part
View Samples- Gallus gallus
- 6 Downloadable Samples
- Affymetrix Chicken Genome Array (chicken)
Description
Myofibroblast is a specific type of mesenchymal cell characterized by synthesis of extracellular matrix and contractile activity. While it serves a beneficial function during tissue wound healing under physiological conditions, it can cause devastating damage to organs afflicted with fibrosis. Myofibroblasts are also present in tumor stroma and contribute actively to tumor growth and spreading. Chicken embryo dermal myofibroblasts (CEDM) represent a novel ex vivo model suitable for the analysis of myofibroblastic phenotype as they show strongly pronounced, uniform and self-sustained myofibroblastic phenotype that is stable in time. As myofibroblastic differentiation is controlled chiefly by TGF-beta signaling, the understanding of the differentiation program entails the determination of TGF-beta-regulated genes. To achieve such a goal, we performed oligonucleotide microarray analysis of CEDM cells treated with a selective TGFBR1 kinase inhibitor. Genes reported previously to be under the control of TGF-beta signaling in mammalian cells appeared among the affected genes also in CEDM cells and many so far unknown TGF-beta targets were revealed.
Publication Title
Molecular analysis of the TGF-beta controlled gene expression program in chicken embryo dermal myofibroblasts.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Gallus gallus
- 6 Downloadable Samples
- Affymetrix Chicken Genome Array (chicken)
Description
The AMV v-Myb oncoprotein causes oncogenic transformation of myelomonocytic cells in vivo and in vitro. Its transforming capacity is strictly dependent upon the N-terminal DNA binding domain, the central transactivation region, and on the C-terminal domain containing a putative leucine zipper motif. While deletions in the central part of the leucine zipper region or point mutations of critical leucine residues abolish the leukemogenicity of the protein, a small deletion within the N-terminal part (deltaP mutant) preserves almost full in vitro transforming ability and only weakens the leukemogenic potential in vivo. We analyzed the gene expression profiles of ex vivo cultures transformed with either wild type or deltaP mutant of v-Myb. A few tens of genes were found to be significantly and reproducibly differentially expressed between the two cultures. Among them, the transcript of the CDKN2A gene, which is critically involved in the cell cycle progression regulation, showed higher expression in the deltaP mutant transformed cells. In mammals and also some avian species, there are two different mRNAs - ARF and INK4A transcribed from the CDKN2A locus. It is known that in chickens the locus had been rearranged in evolution and only one mRNA is transcribed. We found that this mRNA encodes both ARF and INK4A and that the INK4A protein translation starts with a GUG codon downstream of the ARF AUG initiation codon and proceeds in a different reading frame. INK4A protein thus exists in chicken cells as well and its negative regulation by v-Myb is a part of the leukemic transformation mechanism.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part
View Samples- Gallus gallus
- 6 Downloadable Samples
- Affymetrix Chicken Genome Array (chicken)
Description
The neural crest (NC) is a transient dynamic structure of ectodermal origin, found in early vertebrate embryos. The multipotential NC cells migrate along well defined routes, differentiate to various cells types including melanocytes and participate in the formation of various permanent tissues. Abnormal development of NC cells causes several human diseases neurocristopathies. As there is only limited information about the molecular mechanisms controlling early events in melanocyte specification and development, we exploited the AMV v-Myb transcriptional regulator, which directs differentiation of in vitro chicken NC cells to the melanocyte lineage. This activity is strictly dependent on v-Myb specifically binding to the Myb recognition DNA element (MRE). The two tamoxifen-inducible v-myb alleles were constructed, one which recognizes the MRE and one which does not. These were activated in ex-ovo NC cells, and the expression profiles of resulting cells were analyzed using Affymetrix microarrays and RT-PCR. These approaches revealed up-regulation of the BMP antagonist gremlin 2 mRNA, and down-regulation of mRNAs encoding several epithelial genes including KRT19 as very early events following the activation of melanocyte differentiation by v-Myb.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part
View Samples- Gallus gallus
- 4 Downloadable Samples
- Affymetrix Chicken Genome Array (chicken)
Description
Metastatic progression is the leading cause of cancer mortality yet we have an incomplete view of the genetic events governing this process. An investigation was undertaken to explore the role of homeodemain only protein X (HOPX) in metastatic propensity and to identify other genes that may participate in metastasis development. The transcription factor HOPX was assessed for its possible involvement in metastasis formation using a knock-down induced by plasmid-delivered shRNAs. We used our original model system of chicken v-src-transformed tumour cell line PR9692 and its subclone (PR9692-E9) that have lost the ability to induce metastases after inoculation into syngeneic chickens without any significant change in primary tumour formation. We found that also a PR9692 cell line with decreased expression of HOPX gene (PR9692-shHOPX) lost its metastatic capacity in vivo (in chickens) and displayed a reduced cell migration in vitro. We compared the gene expression profiles of control (PR9692-shMOCK) and PR9692-shHOPX cells using oligonucleotide microarrays, assuming that genes with differential expression might be associated with metastasis. The data were compared with a previous study showing differences in gene expression between the PR9692 and PR9692-E9 cells. Bioinformatics was applied to identify gene expression patterns associated with metastasis. 234 genes were identified to show at least 2-fold change in both pairs of cell lines. The results were validated with real-time quantitative RT-PCR and the differential expression was confirmed for several genes. We were also able to demonstrate a significant change at protein level in case of three selected genes (NCAM, FOXG1, ITGA4). shRNA mediated knockdown of one of the identified HOPX regulated genes (integrin alpha 4) in the PR9692 cell line itself showed a marked inhibition of metastasis formation.
Publication Title
Downregulation of HOPX controls metastatic behavior in sarcoma cells and identifies genes associated with metastasis.
Sample Metadata Fields
Cell line
View Samples- Oryza sativa
- 37 Downloadable Samples
- Affymetrix Rice Genome Array (rice)
Description
Plant diurnal oscillation is a 24-hour period based variation. The correlation between diurnal genes and biological pathways was widely revealed by microarray analysis in different species. Rice (Oryza sativa) is the major food staple for about half of the world's population. The rice flag leaf is essential in providing photosynthates to the grain filling. However, there is still no comprehensive view about the diurnal transcriptome for rice leaves. In this study, we applied rice microarray to monitor the rhythmically expressed genes in rice seedling and flag leaves. We developed a new computational analysis approach and identified 6,266 (10.96%) diurnal probe sets in seedling leaves, 13,773 (24.08%) diurnal probe sets in flag leaves. About 65% of overall transcription factors were identified as flag leaf preferred. In seedling leaves, the peak of phase distribution was from 2:00am to 4:00am, whereas in flag leaves, the peak was from 8:00pm to 2:00am. The diurnal phase distribution analysis of gene ontology (GO) and cis-element enrichment indicated that, some important processes were waken by the light, such as photosynthesis and abiotic stimulus, while some genes related to the nuclear and ribosome involved processes were active mostly during the switch time of light to dark. The starch and sucrose metabolism pathway genes also showed diurnal phase. We conducted comparison analysis between Arabidopsis and rice leaf transcriptome throughout the diurnal cycle. In summary, our analysis approach is feasible for relatively unbiased identification of diurnal transcripts, efficiently detecting some special periodic patterns with non-sinusoidal periodic patterns. Compared to the rice flag leaves, the gene transcription levels of seedling leaves were relatively limited to the diurnal rhythm. Our comprehensive microarray analysis of seedling and flag leaves of rice provided an overview of the rice diurnal transcriptome and indicated some diurnal regulated biological processes and key functional pathways in rice.
Publication Title
Transcriptome phase distribution analysis reveals diurnal regulated biological processes and key pathways in rice flag leaves and seedling leaves.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 17 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Dietary interventions are effective ways to extend or shorten lifespan. By examining midlife hepatic gene expressions in mice under different dietary conditions, which resulted in different lifespans and aging-related phenotypes, we were able to identify genes and pathways that modulate the aging process. We found that pathways transcriptionally correlated with diet-modulated lifespan and physiological changes were enriched for lifespan-modifying genes.
Publication Title
Midlife gene expressions identify modulators of aging through dietary interventions.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples