The Hematopoietically-expressed homeobox transcription factor (Hhex) is important for the maturation of definitive hematopoietic progenitors and B-cells during development. We have recently shown that in adult hematopoiesis, Hhex is dispensable for maintenance of hematopoietic stem cells (HSCs) and myeloid lineages but essential for the commitment of Common Lymphoid Progenitors (CLPs) to lymphoid lineages. However, whether Hhex plays a role in HSC self-renewal and myeloid expansion during hematopoietic stress is unknown. Here we show that during serial bone marrow transplantation, Hhex-deleted HSCs are progressively lost, revealing an intrinsic defect in HSC self-renewal. Moreover, Hhex-deleted mice show markedly impaired hematopoietic recovery following myeloablation. In vitro, Hhex-null blast colonies were incapable of replating, implying a specific requirement for Hhex in immature hematopoietic progenitors. Transcriptome analysis of Hhex-null Lin-Sca+Kit+ (LSK) cells showed that Hhex deletion leads to the deregulation of Polycomb Repressive Complex 2 (PRC2) target genes, including an upregulation of Cdkn2a locus, encoding the cell cycle repressors p16Ink4a and p19Arf. Indeed, loss of Cdkn2a restored Hhex-null blast colony replating in vitro, as well as hematopoietic reconstitution following myeloablation in vivo. Thus, HSCs require Hhex to repress Cdkn2a to enable continued self-renewal and response to hematopoietic stress. Overall design: Transcriptional profiling of Hhex-deleted and wild-type LSK cells using RNA sequencing
Hhex Regulates Hematopoietic Stem Cell Self-Renewal and Stress Hematopoiesis via Repression of Cdkn2a.
Specimen part, Cell line, Subject
View SamplesExercise attenuates the development of chronic non-communicable diseases (NCDs). Gene signaling pathway analysis offers an opportunity to discover if electrically induced muscle exercise regulates key pathways among people living with spinal cord injury (SCI). We examined short-term and long-term durations of electrically induced skeletal muscle exercise on complex gene signaling pathways, specific gene regulation, and epigenetic tagging of PGC1a, a major transcription factor in skeletal muscle of men with SCI. After short or long-term electrically induced exercise training, participants underwent biopsies of the trained and untrained muscles. RNA was hybridized to an exon microarray and analyzed using a gene set enrichment analysis. We discovered that long-term exercise training regulated the Reactome gene sets for Metabolism (38 gene sets), Cell Cycle (36 gene sets), Disease (27 gene sets), Gene Expression and Transcription (22 gene sets), Organelle Biogenesis (4 gene sets), Cellular Response to Stimuli (8 gene sets), Immune System (8 gene sets), Vesicle Mediated Transport (4 gene sets), and Transport of Small Molecules (3 gene sets). Specific gene expression included: Oxidative catabolism of glucose including PDHB (p<0.001), PDHX (p<0.001), MPC1 (p<0.009), and MPC2 (p<0.007); Oxidative phosphorylation genes including SDHA (p<0.006), SDHB (p<0.001), NDUFB1 (p<0.002), NDUFA2 (p<0.001); Transcription Genes including PGC1α (p<0.030) and PRKAB2 (p<0.011); Hypertrophy gene MSTN (p<0.001); and the Myokine generating FNDC5 gene (p<0.008). Long-term electrically induced exercise de-methylated the major transcription factor, PGC1a. Taken together, these findings support that long term electrically induced muscle activity regulates key pathways associated with muscle health and systemic metabolism.
Impact of short- and long-term electrically induced muscle exercise on gene signaling pathways, gene expression, and PGC1a methylation in men with spinal cord injury.
Sex, Specimen part, Disease
View SamplesHere, we used next-generation RNA sequencing (RNA-seq) to produce a quantitative, whole genome atlas of gene expression for every excitatory neuronal class in the hippocampus; namely, granule cells and mossy cells of the dentate gyrus, and pyramidal cells of areas CA3, CA2, and CA1. Moreover, for the canonical neurons of the trisynaptic loop, we profiled transcriptomes at both dorsal and ventral poles, producing a cell class- and region-specific transcriptional atlas for these canonical populations. Overall design: Hippocampal RNA profiles were generated by deep sequencing on Illumina HiSeq 2500, with three biological replicates per population
Hipposeq: a comprehensive RNA-seq database of gene expression in hippocampal principal neurons.
Specimen part, Subject
View SamplesTo better understand the mechanisms of blockage of myeloid differentiation and apoptosis and induction of proliferation by miR-125b, we proceeded to identify miR-125b target genes involved in these pathways. We analyzed the total cellular gene expression pattern by RNA-sequencing of the parental NB4 myeloid cell line and that transiently transfected with miR-125b. We generated four cDNA libraries corresponding to duplicates of miR-125b and control cells. Overall design: Compare the gene expression levels in miR control transfected cells with that in miR-125b transfected NB4 cells.Â
MicroRNA-125b transforms myeloid cell lines by repressing multiple mRNA.
Specimen part, Cell line, Subject
View SamplesTo better understand the mechanisms of blockage of myeloid differentiation and apoptosis and induction of proliferation by miR-125b, we preceded to identify miR-125b target genes involved in these pathways. We analyzed the total cellular gene expression pattern by RNA-sequencing of the parental 32Dclone3 myeloid cell line and that ectopically expressing miR-125b. We generated four cDNA libraries corresponding to duplicates of miR-125b and control cells. Overall design: Compare the gene expression level in vector transduced 32Dclone3 cells with that in miR-125b transduced 32Dclone3 cells.Â
MicroRNA-125b transforms myeloid cell lines by repressing multiple mRNA.
Specimen part, Cell line, Subject
View SamplesTissue and organ function has been conventionally understood in terms of the interactions among discrete and homogeneous cell types. This approach has proven difficult in neuroscience due to the marked diversity across different neuron classes, but may also be further hampered by prominent within-class variability. Here, we considered a well-defined, canonical neuronal population – hippocampal CA1 pyramidal cells – and systematically examined the extent and spatial rules of transcriptional heterogeneity. Using next-generation RNA sequencing, we identified striking variability in CA1 PCs, such that the differences along the dorsal-ventral axis rivaled differences across distinct pyramidal neuron classes. This variability emerged from a spectrum of continuous expression gradients, producing a profile consistent with a multifarious continuum of cells. This work reveals an unexpected amount of variability within a canonical and narrowly defined neuronal population and suggests that continuous, within-class heterogeneity may be an important feature of neural circuits. Overall design: Hippocampal RNA profiles were generated by deep sequencing on Illumina HiSeq 2500, with three biological replicates per population
Spatial Gene-Expression Gradients Underlie Prominent Heterogeneity of CA1 Pyramidal Neurons.
Subject
View SamplesWe used a novel approach to study the acute effect of three physiologic stressors (active contractions, vibration, and systemic heat stress) in human skeletal muscle. Three hours after the completion of a dose of physiologic stress, we sampled the soleus (contraction and vibration) or vastus lateralis (heat) muscle and developed a unique gene expression signature for each stressor. We discovered repetitive active muscle contractions up regulated metabolic transcription factors NR4A3 (12.45 fold change), PGC-1 (5.46 fold change), and ABRA (5.98 fold change); and repressed MSTN (0.56 fold change). Heat stress repressed PGC-1 (0.74 fold change); while vibration induced FOXK2 (2.36 fold change). Vibration similarly caused a down regulation of MSTN (0.74 fold change), but to a lesser extent than active muscle contraction. Vibration induced FOXK2 while heat stress repressed PGC-1 (0.74 fold change) and ANKRD1 genes (0.51 fold change). These findings support a distinct gene regulation in response to heat stress, vibration, and muscle contractions. Understanding these responses may assist in developing regenerative rehabilitation interventions to improve muscle cell development, growth, and repair.
Distinct Skeletal Muscle Gene Regulation from Active Contraction, Passive Vibration, and Whole Body Heat Stress in Humans.
Sex, Specimen part
View SamplesThe goal of these studies was to determine the effects of fasting on skeletal muscle mRNA levels in healthy human subjects.
mRNA expression signatures of human skeletal muscle atrophy identify a natural compound that increases muscle mass.
Sex, Age, Specimen part, Treatment, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Effects of Electronic Cigarette Constituents on the Human Lung: A Pilot Clinical Trial.
Age, Specimen part
View SamplesE-cig use is continuing to increase, particularly among youth never-smokers, and is used by some smokers to quit. The acute and chronic toxicity of e-cig use is unclear generally in the context of increasing reports of inflammatory-type pneumonia in some e-cig users. To assess lung effects of e-cigs without nicotine or flavors, we conducted a pilot study with serial bronchoscopies over 4 weeks in 30 never-smokers, randomized either to a four-week intervention with the use of e-cigs containing only 50% propylene glycol (PG) and 50% vegetable glycerine (VG) or to a no-use control group. Compliance to the e-cig intervention was assessed by participants sending daily puff counts and by urinary propylene glycol (PG). Inflammatory cell counts and cytokines were determined in bronchoalveolar lavage (BAL) fluids. Genome-wide expression, microRNA, and mRNA were determined from bronchial epithelial cells. There were no significant differences in changes of BAL inflammatory cell counts or cytokines between baseline and follow-up, comparing the control and e-cig groups. However, in the intervention but not the control group, change in urinary PG as a marker of e-cig use and inhalation, was significantly correlated with change in cell counts (cell concentrations, macrophages, and lymphocytes) and cytokines (IL-8, IL-13, and TNF-α), although the absolute magnitude of changes was small. There were no significant changes in mRNA or microRNA gene expression. Although limited by study size and duration, this is the first experimental demonstration of an impact of e-cig use on inflammation in the human lung among never-smokers.
Effects of Electronic Cigarette Constituents on the Human Lung: A Pilot Clinical Trial.
Age, Specimen part
View Samples