Endothelial cells (EC) lining arteries and veins have distinct molecular and functional signatures. The (epi)genetic regulatory mechanisms underlying this heterogeneity in human EC are incompletely understood. Using genome-wide microarray screening we established a specific fingerprint of freshly isolated arterial (HUAEC) and venous EC (HUVEC) from human umbilical cord comprising 64 arterial and 12 venous genes, representing distinct functions and pathways. Among the arterial genes were 8 transcription factors, including HEY2, a downstream target of Notch signaling and the current golden standard pathway for arterial EC specification. Short-term culture of HUAEC or HUVEC abrogated differential gene expression resulting in a default state. Erasure of arterial gene expression was at least in part due to loss of canonical Notch activity and HEY2 expression. Notably, nCounter analysis revealed that restoring HEY2 expression or Delta-like 4 (Dll4)-induced Notch signaling in cultured HUVEC or HUAEC only partially reinstated the arterial EC gene signature while combined overexpression of the 8 transcription factors restored this fingerprint much more robustly. Each transcription factor had a different impact on gene regulation, with some stimulating only few and others boosting a large proportion of arterial genes. Interestingly, although there was some overlap and cross-regulation, the transcription factors largely complemented each other in regulating the arterial EC gene profile. Thus, our study showed that Notch signaling determines only part of the arterial EC signature and identified additional novel and complementary transcriptional players in the complex regulation of human arteriovenous EC identity
Unraveling a novel transcription factor code determining the human arterial-specific endothelial cell signature.
Specimen partView Samples
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.
No sample metadata fieldsView Samples
see Super Series Summary Overall design: We treated Drosophila S2-DRSC cells for 1, 2, 4 and 20 h with 10 ÂµM JQ1 and compared their gene expression to DMSO-treated control cells (1 and 20 h).
The BET protein FSH functionally interacts with ASH1 to orchestrate global gene activity in Drosophila.
Cell line, Treatment, SubjectView Samples
Background: High density lipoprotein (HDL) protects the artery wall by removing cholesterol from lipid-laden macrophages. However, recent evidence suggests that it might also inhibit atherogenesis by combating inflammation. Methods and Results: To identify potential anti-inflammatory mechanisms, we challenged macrophages with lipopolysaccharide (LPS), an inflammatory microbial ligand for Toll-like receptor 4 (TLR4). HDL inhibited the expression of 33% (301 of 911) of the genes normally induced by LPS, microarray analysis revealed. One of its major targets was the type I interferon response pathway, a family of potent viral immunoregulators controlled by TLR4 and the TRAM/TRIF signaling pathway. Unexpectedly, HDLs ability to inhibit gene expression was independent of cellular cholesterol stores. Moreover, it was unaffected by downregulation of two ATP-binding cassette transporters, ABCA1 and ABCG1, that promote cholesterol efflux. To examine the pathways potential in vivo relevance, we used mice deficient in apolipoprotein (apo) A-I, HDLs major protein. After infection with Salmonella (a Gram-negative bacterium that expresses LPS), apoA-Ideficient mice had 6-fold higher plasma levels of interferon-beta-a key regulator of the type I interferon response than did wild-type mice. Conclusions: HDL inhibits a subset of LPS-stimulated macrophage genes that regulate the type I interferon response, and its action is independent of sterol metabolism. These findings raise the possibility that regulation of macrophage genes by HDL might link innate immunity and cardioprotection.
High-density lipoprotein suppresses the type I interferon response, a family of potent antiviral immunoregulators, in macrophages challenged with lipopolysaccharide.
Specimen partView Samples
Expression profiling using a defined set of iron regulated genes identifies co-regulation of genes and pathways related to inflammatory cytokines
Iron, inflammation, and early death in adults with sickle cell disease.
Specimen part, DiseaseView Samples
We report the single-cell RNA sequencing data obtained from MDA-MB-231 breast cancer cells cultured in standard DMEM with 25 mM glucose, or adapted to culture in DMEM with 10 mM fructose to reduce glycolysis, and then cultured as mammospheres Overall design: Examination of transcriptomic changes in MDA-MB-231 breast cancer cells mammospheres in response to restriction of glycolysis
The effects of restricted glycolysis on stem-cell like characteristics of breast cancer cells.
Cell line, SubjectView Samples
Comparative RNA profiling between tumor cells and their secreted extracellular vesicles. Results revealed enrichment in genes involved in cellular migration and metastasis in extracellular vesicles, in agreement with their role as mediators of tumor progression.
In Vivo imaging reveals extracellular vesicle-mediated phenocopying of metastatic behavior.
Cell lineView Samples
In this study we studied the presence of tumor cells that underwent epithelial-to-mesenchymal transition within polyoma middle T antigen (PyMT) breast tumors. For this we dissociated tumors and isolated Ecad positive tumor cells by FACS sorting. We confirmed that PyMT tumors contain a small set of tumor cells that have undergone EMT in the primary tumor and that E-cadherin can be used as a marker on single cell level for mesenchymal status in this model. Overall design: (i) We isolated primary tumors from mice, dissociated the tumors and FACS-sorted for single Ecad positive tumor cells, after this we performed single cell sequencing of the cells. (ii) We isolated CTCs and solid tumor cells from mice, dissociated the tumors and FACS-sorted for single Ecad positive and negative cells, after this we performed single cell sequencing of the cells.
Plasticity between Epithelial and Mesenchymal States Unlinks EMT from Metastasis-Enhancing Stem Cell Capacity.
Specimen part, SubjectView Samples
Comprehensive analysis of gene expression in hematopoietic stem and progenitor cells from young and old mice.
Quiescent hematopoietic stem cells accumulate DNA damage during aging that is repaired upon entry into cell cycle.
Sex, Age, Specimen part, TimeView Samples
Gene Expression profiling of HSCs isolated at different stages of ontogeny to address correlation between gene expression and changes in DNA methylation
Proliferation-dependent alterations of the DNA methylation landscape underlie hematopoietic stem cell aging.
Sex, Age, Specimen partView Samples