REST is a master regulator of genes that are involved in the acqusition of neuronal fate. The role of REST is not well understood so we attempted to investigate the role of REST in the development of neural cells by analysing the genes that are upregulated when REST is knocked down via shRNA
REST regulates the pool size of the different neural lineages by restricting the generation of neurons and oligodendrocytes from neural stem/progenitor cells.
Specimen part
View SamplesFibrocytes (fibroblastic leukocytes) are recently identified as unique hematopoietic cells with features of both macrophages and fibroblasts. Fibrocytes are known to contribute to the remodeling or fibrosis of various injured tissues. However, their role in viral infection is not fully understood. Here we show that differentiated fibrocytes are phenotypically distinguishable from macrophages but can be infected with HIV-1. Importantly, fibrocytes exhibited persistently infected cell-like phenotypes, the degree of which was more apparent than macrophages. The infected fibrocytes produced replication-competent HIV-1, but expressed HIV-1 mRNA at low levels and strongly resisted HIV-1-induced cell death, which enabled them to support an extremely long-term HIV-1 production at low but steady levels. More importantly, our results suggested that fibrocytes were susceptible to HIV-1 regardless of their differentiation state, in contrast to the fact that monocytes become susceptible to HIV-1 after the differentiation into macrophages. Our findings indicate that fibrocytes are the previously unreported HIV-1 host cells, and suggest the importance of considering fibrocytes as one of long-lived persistently infected cells for curing HIV-1.
Fibrocytes Differ from Macrophages but Can Be Infected with HIV-1.
Specimen part, Time
View Samples3D cultivation of cells lead to changes in morphology of the cells. This is likely to explain the higher radioresistance of cells growing in 3D compared to cells growing in 2D cell culture.
Genome-wide gene expression analysis in cancer cells reveals 3D growth to affect ECM and processes associated with cell adhesion but not DNA repair.
Specimen part, Cell line
View SamplesAtherosclerosis and pressure overload are major risk factors for the development of heart failure in patients. Cardiac hypertrophy often precedes the development of heart failure. However, underlying mechanisms are incompletely understood. To investigate pathomechanisms underlying the transition from cardiac hypertrophy to heart failure we used experimental models of atherosclerosis- and pressure overload-induced cardiac hypertrophy and failure, i.e. apolipoprotein E (apoE)-deficient mice, which develop heart failure at an age of 18 months, and non-transgenic C57BL/6J (B6) mice with heart failure triggered by 6 months of pressure overload induced by abdominal aortic constriction (AAC). The development of heart failure was monitored by echocardiography, invasive hemodynamics and histology. The microarray gene expression study of cardiac genes was performed with heart tissue from failing hearts relative to hypertrophic and healthy heart tissue, respectively. The microarray study revealed that the onset of heart failure was accompanied by a strong up-regulation of cardiac lipid metabolism genes involved in fat synthesis, storage and oxidation.
Up-regulation of the cardiac lipid metabolism at the onset of heart failure.
Age, Specimen part, Disease
View SamplesHeart failure is a leading cause of cardiovascular mortality with limited options for treatment. We used 18 month-old apolipoprotein E (apoE)- deficient mice as a model of atherosclerosis-induced heart failure to analyze whether the anti-ischemic drug ranolazine could retard the progression of heart failure. The study showed that 2 months of ranolazine treatment improved cardiac function of 18 month-old apoE-deficient mice with symptoms of heart failure as assessed by echocardiography. To identify changes in cardiac gene expression induced by treatment with ranolazine a microarray study was performed with heart tissue from failing hearts relative to ranolazine-treated and healthy control hearts. The microarray approach identified heart failure-specific genes that were normalized during treatment with the anti-ischemic drug ranolazine.
Up-regulation of the cardiac lipid metabolism at the onset of heart failure.
Age, Specimen part, Disease, Treatment
View SamplesThe human nm23-H1 was discovered as a tumor metastasis suppressor based on its reduced expression in melanoma cell lines with low versus high metastatic potential. It encodes for one of two subunits of the nucleoside-diphosphate kinase. Besides its role in the maintenance of the cells NTP pool, nm23 plays a key role in different cellular processes. The role of nm23-H1 in these processes still has to be elucidated. Our goal was to identify Nm23-H1 downstream targets by subjecting Nm23-H1 overexpressing CAL 27 cells oral squamous cell carcinoma (OSSC) to microarray analysis. The genes with changed expression patterns could be clustered into several groups: transforming growth factor (TGF) signaling pathway, cell adhesion, invasion and motility, proteasome machinery, cell-cycle, epithelial structural and related molecules and others. Based on the expression patterns observed we presume that nm23-H1 might have a role in OSSCs, which should be confirmed by future experiments.
Downstream targets of Nm23-H1: gene expression profiling of CAL 27 cells using DNA microarray.
Specimen part, Disease, Disease stage, Cell line
View SamplesTo determne JunB target gene in human keratincoytes Mice with epidermal deletion of JunB transcription factor displayed a psoriasis-like inflammation. The relevance of these findings to humans and the mechanisms mediating JunB function are not fully understood. Here, we demonstrate that impaired JunB function via gene silencing or overexpression of a dominant negative mutant increased human keratinocyte cell proliferation but decreased cell barrier function. RNA-seq revealed over 500 genes affected by JunB loss-of-function which included an upregulation of an array of proinflammatory molecules relevant to psoriasis. Among these were TNFa, CCL2, CXCL10, IL6R and SQSTM1, an adaptor protein involved in NF-kB activation. ChIP-Seq and gene reporter analyses showed that JunB directly suppressed SQSTM1 through binding to a consensus AP-1 cis-element located around 2 Kb upstream of SQSTM1-trasncription start site. Similar to JunB loss-of-function, SQSTM1-overexpression induced TNFa, CCL2 and CXCL10. Conversely, NF-kB-inhibition genetically with a mutant IkBa or pharmacologically with PDTC prevented cytokine, but not IL6R, induction by JunB-deficiency. Taken together, our findings indicate that JunB controls epidermal growth, barrier formation and proinflammatory responses through direct and indirect mechanisms, pinpointing SQSTM1 as a key mediator of JunB-suppression of NF-kB-dependent inflammation. Overall design: 3 indepdent set of priamry human keratinocytes isolated from foreskin skin samples were transfected with nonsilencing control or siRNA oligonucleotides targeting JunB. mRNA was then isolated and used for cDNA library construction followed by RNA-sequencing.
RNA-Seq and ChIP-Seq reveal SQSTM1/p62 as a key mediator of JunB suppression of NF-κB-dependent inflammation.
No sample metadata fields
View SamplesPositioned nucleosomes limit the access of proteins to DNA and implement regulatory features encoded in eukaryotic genomes. Here we generated the first genome-wide nucleosome positioning map for Schizosaccharomyces pombe and annotated transcription start and termination sites genome-wide. Using this resource we found surprising differences compared to the nucleosome organization in the distantly related yeast Saccharomyces cerevisiae [the cerevisiae data has been published by others (PMID: 17873876) and the raw data is deposited at ArrayExpress(E-MEXP-1172)]. DNA sequence guides nucleosome positioning differently, e.g., poly(dA:dT) elements are not enriched in S. pombe nucleosome-depleted regions (NDRs). Regular nucleosomal arrays emanate more asymmetrically, i.e., mainly co-directionally with transcription, from promoter NDRs, but promoters harbouring the histone variant H2A.Z show regular arrays also upstream. Regular nucleosome phasing in S. pombe has a very short repeat length of 154 base pairs, and requires a remodeler, Mit1, conserved in humans but not found in S. cerevisiae. Nucleosome positioning mechanisms are evidently not universal but evolutionarily plastic.
Schizosaccharomyces pombe genome-wide nucleosome mapping reveals positioning mechanisms distinct from those of Saccharomyces cerevisiae.
No sample metadata fields
View SamplesBackground. Nuclear factor I-A (NFI-A), a phylogenetically conserved transcription/replication protein, plays a crucial role in mouse brain development. Previous studies showed that disruption of the Nfia gene in mice leads to perinatal lethality, corpus callosum agenesis, and hydrocephalus.
Gene expression analysis of nuclear factor I-A deficient mice indicates delayed brain maturation.
No sample metadata fields
View SamplesFew families of signaling factors have been implicated in the control of development. Here we identify the neuropeptides nociceptin and somatostatin, a neurotransmitter and neuroendocrine hormone, as a class of developmental signals in chick and zebrafish. We show that signals from the anterior mesendoderm are required for the formation of anterior placode progenitors with one of the signals being somatostatin. Somatostatin controls ectodermal expression of nociceptin and both peptides regulate Pax6 in lens and olfactory progenitors. Consequently, loss of somatostatin and nociceptin signaling leads to severe reduction of lens formation. Our findings not only uncover these neuropeptides as developmental signals, but also identify a long-sought-after mechanism that initiates Pax6 in placode progenitors and may explain the ancient evolutionary origin of neuropeptides, pre-dating a complex nervous system.
Neuropeptides: developmental signals in placode progenitor formation.
Specimen part
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