We generated whole genome expression profiles from a homogeneous population of purified pacemaker neurons (ventral Lateral Neurons, LNvs) from wild type and clock mutant Drosophila. The study identifes a group of genes whose expression is highly enriched in LNvs compared to other neurons; and a second group of genes rhythmically expressed in LNvs in a clock-dependent manner.
A mechanism for circadian control of pacemaker neuron excitability.
Specimen part
View SamplesWe report the application of bi-species RNAseq for investigating mechanisms of reprogramming towards pluripotency using heterokaryons (mouse embryonic stem cell X human fibroblast cell fusions). The use of mixed species allows one to monitor reprogramming of the human somatic nuclei independently of contributions from the mouse nuclei using nucleotide differences. We used RNAseq to monitor heterokaryon reprogramming over a 3-day timecourse, generating transcriptome-wide data for cell fusion based reprogramming of human fibroblasts towards pluripotency. Overall design: Examination of cellular reprogramming over a heterokaryon timecourse (mouse embryonic stem cells X human fibroblasts)
Early role for IL-6 signalling during generation of induced pluripotent stem cells revealed by heterokaryon RNA-Seq.
Disease, Subject, Time
View SamplesWe used heterokaryon cell fusion based reprogramming and identified the cytokine IL6 as a potential regulator of reprogramming to pluripotency. We generated iPS clones using the four reprogramming factors (4F) Oct4, Klf4, Sox2, and c-Myc. In addition, iPS clones were generated using only three factors (3F: Oct4, Klf4, amd Sox2) with the addition of the cytokine IL6 to reprogramming culture conditions. Global RNA-Seq of the 3F + IL6 derived iPS clones was done for comparison with 4F-derived iPS clones, mouse embryonic stem cells and mouse embryonic fibroblasts. Overall design: This study includes 8 samples: 2 independently derived 3F + IL6 iPS clones, 2 independently derived 4F iPS clones, 2 biological replicates of mouse D3-GFP ES cells, and 2 biological replicates of mouse embryonic fibroblasts (MEFs). The latter 6 samples are provided as references for the 3F + IL6 iPS clones. Poly-A RNA was isolated and prepared for sequencing using the Illumina TruSeq RNA kit (v2) to generate 50bp reads. Reads were aligned to mm10.
NKX3-1 is required for induced pluripotent stem cell reprogramming and can replace OCT4 in mouse and human iPSC induction.
Specimen part, Treatment, Subject
View SamplesAlthough glucocorticoids (GCs) are known to exert numerous effects in the hippocampus, their chronic regulatory functions remain poorly understood. Moreover, evidence is inconsistent regarding the longstanding hypothesis that chronic GC exposure promotes brain aging/Alzheimer's disease. Here, we adrenalectomized male F344 rats at 15-months-of-age, maintained them for 3 months with implanted corticosterone (CORT) pellets producing low or intermediate (glucocorticoid-receptor (GR)-activating) blood levels of CORT, and performed microarray/pathway analyses in hippocampal CA1. We defined the chronic GC-dependent transcriptome as 393 genes that exhibited differential expression between Intermediate- and Low-CORT groups. Short-term CORT (4 days) did not recapitulate this transcriptome. Functional processes/pathways overrepresented by chronic CORT-upregulated genes included learning/plasticity, differentiation, glucose metabolism and cholesterol biosynthesis, whereas processes overrepresented by CORT-downregulated genes included inflammatory/immune/glial responses and extracellular structure. These profiles indicate that GCs chronically activate neuronal/metabolic processes while coordinately repressing a glial axis of reactivity/inflammation. We then compared the GC-transcriptome with a previously-defined hippocampal aging transcriptome, revealing a high proportion of common genes. Although CORT and aging moved expression of some common genes in the same-direction, the majority were shifted in opposite directions by CORT and aging (e.g., glial inflammatory genes downregulated by CORT are upregulated with aging). These results contradict the hypothesis that GCs simply promote brain aging, and also suggest that the opposite-direction shifts during aging reflect resistance to CORT regulation. Therefore, we propose a new model in which aging-related GC resistance develops in some target pathways while GC overstimulation develops in others, together generating much of the brain aging phenotype.
Glucocorticoid-dependent hippocampal transcriptome in male rats: pathway-specific alterations with aging.
Sex, Age, Specimen part
View SamplesTargeted deletion of skNAC in mice resulted in early embryonic lethality with cardiac defects. In order to investigate the molecular mechanism of the cardiac defect, we designed the microarray comparing gene expression of the mutant E11.5 heart to wild type E11.5 heart.
skNAC, a Smyd1-interacting transcription factor, is involved in cardiac development and skeletal muscle growth and regeneration.
Specimen part
View SamplesThis study characterizes the response of primary human endothelial cells (human umbilical vein endothelial cells, HUVECs) to the relative shear stress changes that occur during the initiation of arteriogenesis at the entrance regions to a collateral artery network. HUVECs were preconditioned to a baseline level of unidirectional shear of 15 dynes/cm2 for 24 hours. After 24 hours preconditioning, HUVECs were subjected to an arteriogenic stimulus that mimics the shear stress changes observed in the opposing entrance regions into a collateral artery network. The arteriogenic stimulus consisted of a 100% step wise increase in shear stress magnitude to a unidirectional 30 dynes/cm2 in either the same or opposite direction of the preconditioned shear stress. This simulates either the feeding entrance to the collateral artery circuit or the region that drains into the vasculature downstream of an obstruction in a major artery, respectively. In vivo analysis of collateral growth in the mouse hindlimb showed enhanced outward remodeling in the re-entrant (direction reversing) region that reconnects to the downstream arterial tree, suggesting reversal of shear stress direction as a key enhancer of arteriogenesis. Transcriptional profiling using microarray techniques identified that the reversal of shear stress direction, but not an increase in shear stress alone, yielded a broad-based enhancement of the mechanotransduction pathways necessary for the induction of arteriogenesis.
Mechanisms of Amplified Arteriogenesis in Collateral Artery Segments Exposed to Reversed Flow Direction.
Specimen part
View SamplesMany animal species employ a chromosome-based mechanism of sex determination, which has led to coordinate evolution of dosage compensation systems. Dosage compensation not only corrects the imbalance in the number of X-chromosomes between the sexes, but is also hypothesized to correct dosage imbalance within cells due to mono-allelic X expression and bi-allelic autosomal expression, by upregulating X-linked genes (termed â??Ohnoâ??s hypothesisâ??). Although this hypothesis is well supported by expression analyses of individual X-linked genes and by array-based transcriptome analyses, a recent study claimed that no such X upregulation exists in mammals and C. elegans based on RNA-sequencing and proteomics analyses. We provide RNA-seq RNA-seq analysis of mouse female PGK12.1 ES cells with two active X chromosomes and confirmed that the X chromosome is upregulated, consistent with the previous microarray study. Overall design: Examination of expression of X-linked and autosomal genes in mouse female ES cells with two active X chromosomes.
Bipartite structure of the inactive mouse X chromosome.
Sex, Cell line, Subject
View SamplesRegeneration of skeletal muscle is dependent on the function of tissue-resident muscle stem cells (MuSC), known as satellite cells. MuSC dysfunction is central to muscle pathophysiology, including in age-associated loss of muscle regenerative capacity and congenital disorders such as Duchenne muscular dystrophy. Despite the central role of satellite cells in muscle regeneration, the signals controlling the balance between muscle stem cell quiescence, proliferation, and differentiation remain incompletely understood. Knowledge of the signals that maintain a quiescent state is particularly lacking, yet such cues are crucial to maintaining a stem cell reservoir that can meet the needs of regeneration throughout life. Here we identify Oncostatin M (OSM), a member of the interleukin-6 family of cytokines, as a potent and essential trans-acting regulator of satellite cell quiescence. Key to this discovery is the development of a novel in vivo imaging-based screening strategy allowing identification of proteins that do not induce in vitro proliferation, but instead maintain MuSCs in a non-mitotic state, poised for rapid robust expansion upon transplantation. We demonstrate that OSM induces reversible exit from the cell cycle and induction of a global transcriptional program significantly enriched within a newly established satellite cell quiescence signature. Genetic ablation of the OSM receptor in mice demonstrates that signaling via OSM/R is essential for maintenance of satellite cell quiescence, and for proper skeletal muscle regeneration in vivo. Given that aberrant activation and exhaustion of stem cells is seen in a variety of disorders, OSM constitutes an attractive therapeutic target in muscle disease states.
Induction of muscle stem cell quiescence by the secreted niche factor Oncostatin M.
Age, Specimen part
View SamplesBackground: Mycobacterium tuberculosis infection is a leading cause of infectious death worldwide. Gene-expression microarray studies profiling the blood transcriptional response of tuberculosis (TB) patients have been undertaken in order to better understand the host immune response as well as to identify potential biomarkers of disease. To date most of these studies have focused on pulmonary TB patients with gene-expression profiles of extra-pulmonary TB patients yet to be compared to those of patients with pulmonary TB or sarcoidosis.
The Transcriptional Signature of Active Tuberculosis Reflects Symptom Status in Extra-Pulmonary and Pulmonary Tuberculosis.
Sex, Age, Specimen part, Disease, Disease stage, Race
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A machine learning approach to integrate big data for precision medicine in acute myeloid leukemia.
Age, Specimen part, Disease, Disease stage
View Samples