Activation of the AKT and ERK signaling pathway is a major contributor to cell proliferation. However, the integrated regulation of this multistep process, involving signal processing, cell growth and cell-cycle progression, is poorly understood. Here we study three cell types of hematopoietic origin, in which AKT and ERK signaling is triggered by erythropoietin (Epo). We find that the different cell types exhibit distinct proliferative responses, despite sharing the molecular network for pro-proliferative signaling. Iterating quantitative experiments and mathematical modeling, we show that the cell-type-specific regulation of proliferation emerges from two sources: (1) the protein abundance patterns of signaling components that cause differential flow of signals along the AKT and ERK pathways, and (2) the differential impact of the downstream regulators for protein synthesis and for cell-cycle progression on proliferation. Our integrated mathematical model of Epo-driven proliferation explains cell-type-specific effects of targeted AKT and ERK inhibitors and correctly predicts whether their combined application results in synergy.
Protein abundance of AKT and ERK pathway components governs cell type-specific regulation of proliferation.
Sex, Cell line
View SamplesThree groups of German Landrace piglets were vaccinated with tetanus toxoid. Transcriptome profiles of PBMC were analysed from blood samples taken 0, 2, 4, 8, 24 and 75 hours after a first vaccination and 0, 2, 4, 8, 24 and 75 hours as well as 14 d after a second vaccination on day 14.
Transcriptomic response of porcine PBMCs to vaccination with tetanus toxoid as a model antigen.
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View SamplesAldosterone is known to have a number of direct adverse effects on the heart, including fibrosis and myocardial inflammation. However, genetic mechanisms of aldosterone action on the heart remain unclear.
Effect of acute aldosterone administration on gene expression profile in the heart.
No sample metadata fields
View SamplesTransdifferentiation has been recently described as a novel method for converting human fibroblasts into induced cardiomyocyte-like cells. Such an approach can produce differentiated cells to study physiology or pathophysiology, examine drug interactions or toxicities, and engineer tissues. Here we describe the transdifferentiation of human dermal fibroblasts towards the cardiac cell lineage via the induced expression of transcription factors (TFs) GATA4, TBX5, MEF2C, MYOCD, NKX2-5, and delivery of microRNAs miR-1 and miR-133a. Cells undergoing transdifferentiation expressed ACTN2 and TNNT2 and partially organized their cytoskeleton in a cross-striated manner. The conversion process was associated with significant upregulation of a cohort of cardiac-specific genes, activation of pathways associated with muscle contraction and physiology, and downregulation of fibroblastic markers. We used a genetically encoded calcium indicator and readily detected active calcium transients although no spontaneous contractions were observed in transdifferentiated cells. Finally, we determined that inhibition of Janus kinase 1, inhibition of glycogen synthase kinase 3, or addition of NRG1 significantly enhanced the efficiency of transdifferentiation. Overall, we describe a method for achieving transdifferentiation of human dermal fibroblasts into induced cardiomyocyte-like cells via transcription factor overexpression, microRNA delivery, and molecular pathway manipulation.
Core Transcription Factors, MicroRNAs, and Small Molecules Drive Transdifferentiation of Human Fibroblasts Towards The Cardiac Cell Lineage.
Specimen part, Treatment, Time
View SamplesRegional identity of several kind of human neural stem cells were assessed by RNA-Seq Overall design: We compared whole transcriptome of human fetal spinal cord, fetal brain, fetal spinal cord derived NSCs, H9-derived NSCs, H9-derived spinal cord NSCs, and UCSF4-derived spinal cord NSCs
Generation and post-injury integration of human spinal cord neural stem cells.
Specimen part, Subject
View SamplesTransient over-expression of defined combinations of master regulator genes can effectively induce cellular reprogramming: the acquisition of an alternative predicted phenotype from a differentiated cell lineage. This can be of particular importance in cardiac regenerative medicine wherein the heart lacks the capacity to heal itself, but simultaneously contains a large pool of fibroblasts. In this study we determined the cardio-inducing capacity of ten transcription factors to actuate cellular reprogramming of mouse embryonic fibroblasts into cardiomyocyte-like cells. Over-expression of transcription factors MYOCD and SRF alone or in conjunction with Mesp1 and SMARCD3 significantly enhanced the basal but necessary cardio-inducing effect of the previously reported GATA4, TBX5, and MEF2C. In particular, combinations of five or seven transcription factors significantly enhanced the activation of cardiac reporter vectors, and induced an upregulation of cardiac-specific genes. Global gene expression analysis also demonstrated a significantly greater cardio-inducing effect when the transcription factors MYOCD and SRF were used. Detection of cross-striated cells was highly dependent on the cell culture conditions and was enhanced by the addition of valproic acid and JAK inhibitor. Although we detected Ca2+ transient oscillations in the reprogrammed cells, we did not detect significant changes in resting membrane potential or spontaneously contracting cells. This study further elucidates the cardio-inducing effect of the transcriptional networks involved in cardiac cellular reprogramming, contributing to the ongoing rational design of a robust protocol required for cardiac regenerative therapies.
Transcription factors MYOCD, SRF, Mesp1 and SMARCD3 enhance the cardio-inducing effect of GATA4, TBX5, and MEF2C during direct cellular reprogramming.
Specimen part
View SamplesPancreatic islet cells are critical for maintaining normal blood glucose levels and their malfunction underlies diabetes development and progression. We used single-cell RNA sequencing to determine the transcriptomes of 1,492 human pancreatic a-, ß-, d- and PP cells from non-diabetic and type 2 diabetes organ donors. We identified cell type specific genes and pathways as well as 245 genes with disturbed expression in type 2 diabetes. Importantly, 92% of the genes have not previously been associated with islet cell function or growth. Comparison of gene profiles in mouse and human a- and ß-cells revealed species-specific expression. All data are available for online browsing and download and will hopefully serve as a resource for the islet research community. Overall design: Single-cell RNA sequencing of human non-diabetic and type 2 diabetic pancreatic islet cells
RNA Sequencing of Single Human Islet Cells Reveals Type 2 Diabetes Genes.
Sex, Age, Specimen part, Race, Subject
View SamplesAging improves pancreatic ß-cell function in mice. This is a surprising finding since aging is typically associated with functional decline. We performed single-cell RNA sequencing of ß-cells from 3 and 26 month old mice to explore how changes in gene expression contribute to improved function with age. The old mice were healthy, had reduced blood glucose levels and increased ß-cell mass, which correlated to their body weight. ß-cells from young and old mice had similar transcriptome profiles. In fact, only 193 genes (0.89% of all detected genes) were significantly regulated (= 2-fold; false discovery rate < 0.01; normalized counts > 5). Of these, 183 were downregulated and mainly associated with pathways regulating gene expression, cell cycle, cell death and survival as well as cellular movement, function and maintenance. Collectively, our data show that ß-cells from very old mice have transcriptome profiles similar to those of young mice. These data support previous findings that aging is not associated with reduced ß-cell mass or functional ß-cell decline in mice. Overall design: Single-cell RNA sequencing of mouse pancreatic islet beta cells
Single-Cell RNAseq Reveals That Pancreatic β-Cells From Very Old Male Mice Have a Young Gene Signature.
Sex, Age, Specimen part, Subject
View SamplesCell communication within tissues is mediated by multiple paracrine signals including growth factors, which control cell survival and proliferation. Cells and the growth factors they produce and receive constitute a circuit, yet the design features of cell circuits involved in tissue homeostasis are unknown. Here we used computational and experimental approaches to characterize the features of cell circuits based on growth factor exchange between macrophages and fibroblasts, two cell types found in most mammalian tissues. We found that the macrophage-fibroblast cell circuit is stable and robust to perturbations. We employed analytical screening of all possible two-cell circuit topologies and defined the circuit features sufficient for stability, including environmental constraint and negative feedback regulation. Moreover, we discovered that cell-cell contact was essential for the stability of the macrophage-fibroblast circuit. These findings highlight general principles of cell circuit design, and provide a new perspective on quantitative understanding of tissue homeostasis. Overall design: 1 sample of murine embryonic fibroblast and 1 sample murine bone marrow derived macrophages are analyzed for their expression of growth factors and growth factor receptors
Circuit Design Features of a Stable Two-Cell System.
Specimen part, Cell line, Subject
View SamplesThis study provides an assessment of the Fluidigm C1 platform for RNA sequencing of single mouse pancreatic islet cells. The system combines microfluidic technology and nanoliter-scale reactions. We sequenced 622 cells allowing identification of 341 islet cells with high-quality gene expression profiles. The cells clustered into populations of alpha-cells (5%), beta-cells (92%), delta-cells (1%) and PP-cells (2%). We identified cell-type specific transcription factors and pathways primarily involved in nutrient sensing and oxidation and cell signaling. Unexpectedly, 281 cells had to be removed from the analysis due to low viability (23%), low sequencing quality (13%) or contamination resulting in the detection of more than one islet hormone (64%). Collectively, we provide a resource for identification of high-quality gene expression datasets to help expand insights into genes and pathways characterizing islet cell types. We reveal limitations in the C1 Fluidigm cell capture process resulting in contaminated cells with altered gene expression patterns. This calls for caution when interpreting single-cell transcriptomics data using the C1 Fluidigm system. Overall design: Single-cell RNA sequencing of mouse C57BL/6 pancreatic islet cells
Use of the Fluidigm C1 platform for RNA sequencing of single mouse pancreatic islet cells.
Specimen part, Cell line, Subject
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