In contrast to urodele amphibians and teleost fish, mammals lack the regenerative responses to replace large body parts. Amphibian and fish regeneration uses dedifferentiation, i.e. reversal of differentiated state, as a means to produce progenitor cells to eventually replace damaged tissues. Therefore, activation of dedifferentiation response in mammalian tissues holds an immense promise for human regenerative medicine. msx2 expression has been shown to peak at the early time points of amphibian limb regeneration. Despite this temporal importance in the heterogenous regenerating limb tissues, the potential role of msx2 in dedifferentiation was previously not addressed in salamander or mammalian muscle cells. In order to test this, we ectopically overexpressed msx2 in mammalian myotubes and profiled their transcriptomes using next generation sequencing. We identified 4964 up-regulated and 4464 down-regulated transcripts in myotubes compared to myoblasts (uninduced GFP control cells; = 1.5 fold; FDR corrected p-values < 0.01). Upon ectopic msx2 expression in myotubes, 923 transcripts were downregulated, whereas 1283 transcripts were upregulated. Based on msx2's potential role in dedifferentiation, we reasoned that the transcripts, which are normally upregulated in myotubes in comparison to myoblasts, should go down upon msx2-expression. In accord with this idea, 575 myotube-enriched transcripts were downregulated after one day of ectopic msx2 expression. Similarly, 331 myoblast-enriched transcripts were upregulated upon msx2 expression. Overall design: To extensively analyze transcriptome-wide changes upon ectopic msx2 expression in mammalian myotubes, we performed next generation RNA-sequencing (RNA-seq) on uninduced and induced isolated myotubes that have msx2 and GFP or GFP alone transgenes. As a reference for the undifferentiated state, we also sequenced the transcriptomes of uninduced myoblast cultures of these two transgenic constructs. Deep sequencing was performed using Illumina HiSeq.
Ectopic expression of Msx2 in mammalian myotubes recapitulates aspects of amphibian muscle dedifferentiation.
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View Samplesexpression profiles kPSCs versus cMSC
The human kidney capsule contains a functionally distinct mesenchymal stromal cell population.
Specimen part
View SamplesThis is an initial experiment which was performed in order to identify novel transcriptional targets of the tumor suppressor p53
p53 activates the PANK1/miRNA-107 gene leading to downregulation of CDK6 and p130 cell cycle proteins.
Specimen part, Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
COLOMBOS v2.0: an ever expanding collection of bacterial expression compendia.
No sample metadata fields
View SamplesGene expression from Escherichia coli.
COLOMBOS v2.0: an ever expanding collection of bacterial expression compendia.
No sample metadata fields
View SamplesWe used microarrays to compare gene expression across different murine tissues.
Using ribosomal protein genes as reference: a tale of caution.
No sample metadata fields
View SamplesTo unravel the molecular mechanisms mediating the effects of androgens on spermatogenesis, testicular gene expression was compared in mice with a Sertoli cell-selective androgen receptor knockout (SCARKO) and littermate controls on postnatal d 10. At this age testicular cell composition is still comparable in SCARKOs and controls. Microarray analysis identified 692 genes with significant differences in expression. A more than 2-fold up- or downregulation by androgen action in Sertoli cells was observed for 28 and 6 genes respectively. The biological relevance of the strongly upregulated genes was supported by the finding that several of them were previously described to be androgen-regulated or essential for spermatogenesis. Serine protease inhibitors were overrepresented in the same subgroup suggesting a role for androgens in cell junction dynamics and tissue restructuring events during spermatogenesis. A time course experiment (d8-d20), followed by cluster analysis allowed the identification of typical expression patterns of differentially expressed testicular genes during initiation of spermatogenesis. Three genes with a pattern closely resembling that of Pem, a prototypal androgen-regulated gene in Sertoli cells, were selected for confirmation by RT-PCR and further analysis. The data confirm that the SCARKO model allows identification of novel androgen-regulated genes in the testis. This particular series represents all data from d 10. The additional expression data from the time course (d8-d20) is represented by series GSE2259 ("Testicular gene expression in SCARKO mice during prepuberty").
The effect of a sertoli cell-selective knockout of the androgen receptor on testicular gene expression in prepubertal mice.
No sample metadata fields
View SamplesTo unravel the molecular mechanisms mediating the effects of androgens on spermatogenesis, testicular gene expression was compared in mice with a Sertoli cell-selective androgen receptor knockout (SCARKO) and littermate controls on postnatal d 10. At this age testicular cell composition is still comparable in SCARKOs and controls. Microarray analysis identified 692 genes with significant differences in expression. A more than 2-fold up- or downregulation by androgen action in Sertoli cells was observed for 28 and 6 genes respectively. The biological relevance of the strongly upregulated genes was supported by the finding that several of them were previously described to be androgen-regulated or essential for spermatogenesis. Serine protease inhibitors were overrepresented in the same subgroup suggesting a role for androgens in cell junction dynamics and tissue restructuring events during spermatogenesis. A time course experiment (d8-d20), followed by cluster analysis allowed the identification of typical expression patterns of differentially expressed testicular genes during initiation of spermatogenesis. Three genes with a pattern closely resembling that of Pem, a prototypal androgen-regulated gene in Sertoli cells, were selected for confirmation by RT-PCR and further analysis. The data confirm that the SCARKO model allows identification of novel androgen-regulated genes in the testis.
The effect of a sertoli cell-selective knockout of the androgen receptor on testicular gene expression in prepubertal mice.
No sample metadata fields
View SamplesWe found that LSD1 inhibition by a monoamine oxidase inhibitor, tranylcypromine (TC), could enhance fetal gamma globin expression.
Lysine-specific demethylase 1 is a therapeutic target for fetal hemoglobin induction.
Treatment
View SamplesTo understand organ function it is important to have an inventory of the cell types present in the tissue and of the corresponding markers that identify them. This is a particularly challenging task for human tissues like the pancreas, since reliable markers are limited. Transcriptome-wide studies are typically done on pooled islets of Langerhans, which obscures contributions from rare cell types and/or potential subpopulations. To overcome this challenge, we developed an automated single-cell sequencing platform to sequence the transcriptome of thousands of single pancreatic cells from deceased organ donors, allowing in silico purification of all main pancreatic cell types. We identify cell type-specific transcription factors, a subpopulation of REG3A-positive acinar cells, and cell surface markers that allow sorting of live alpha and beta cells with high purity. This resource will be useful for developing a deeper understanding of pancreatic biology and pathophysiology of diabetes mellitus. Overall design: Islets of Langerhans were extracted from human cadaveric pancreata and kept in culture until single-cell dispersion and FACS sorting. Single-cell transcriptomics was performed on live cells from this mixture using an automated version of CEL-seq2 on live, FACS sorted cells. The StemID algorithm was used to identify clusters of cells corresponding to the major pancreatic cell types and to mine for novel cell type-specific genes as well as subpopulations within the known pancreatic cell types.
A Single-Cell Transcriptome Atlas of the Human Pancreas.
Specimen part, Subject
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