WOX5 maintains columella stem cells in the Arabidopsis root and prevents their differentiation. In order to understand the molecular mode of WOX5 action the genes differentially expressed by WOX5 inducible over-expression were determined by analysis of microarray hybridizations. Seedlings transformed with a dexamethasone inducible WOX5 construct were induced for one or four hours with dexamethasone or a mock solution. Other seedlings were treated one hour with cycloheximide ( a protein synthesis inhibitor to reduce secondary transcriptional effects after WOX5 activation) and either dexamethasone or a mock solution. Root tips were harvested, RNA extracted, and the RNA samples prepared for hybridization to Affymetrix microarrays. Potential target genes of WOX5 were further analyzed by transcriptional markers, qPCR and EMSA (electrophoretic mobility shift assay).
Organizer-Derived WOX5 Signal Maintains Root Columella Stem Cells through Chromatin-Mediated Repression of CDF4 Expression.
Specimen part, Compound, Time
View SamplesNormal pregnancy requires adaptations of the maternal vasculature. During preeclampsia these adjustments are not well established, resulting in maternal hypertension and proteinuria. The effects of preeclampsia on the maternal vasculature are not yet fully understood. We aimed to identify gene expression differences in the aorta between non pregnant, healthy pregnant, and experimental preeclamptic rats using a genome wide approach.
Experimental preeclampsia in rats affects vascular gene expression patterns.
Specimen part
View SamplesPlasmacytoid dendritic cells (pDCs) play a critical role in bridging the innate and adaptive immune systems. pDCs are specialized type I interferon (IFN) producers, which has implicated them as initiators of autoimmune pathogenesis. However, little is known about the down-stream effectors of type I IFN signaling that amplify autoimmune responses. Here we have used a chemokine reporter mouse to determine the CXCR3 ligand responses in DCs subsets. Following TLR7 stimulation conventional type 1 and type 2 DCs (cDC1 and cDC2 respectively) uniformly upregulate CXCL10. By contrast, the proportion of chemokine positive pDCs was significantly less, and stable CXCL10+ and CXCL10 - populations could be distinguished. CXCL9 expression was induced in all cDC1s, in half of the cDC2 but not by pDCs. In all DC subsets, type I IFNs were the main inducer of CXCR3 chemokines, as IFNAR receptor blocking or deficiency completely abrogated reporter expression. Chemoki ne producing potential was not concordant with the previously identified markers of pDC heterogeneity. Finally, we show that CXCL10+ and CXCL10 - populations are transcriptionally distinct, expressing unique transcriptional regulators, IFN signaling molecules, chemokines, cytokines and cell surface markers. This work highlights CXCL10 as a downstream effector of type I IFN signaling and suggests a division of labor in pDCs subtypes that likely impacts their function as effectors of viral responses and as drivers of inflammation. Overall design: Comparison of gene expression in different haematopoietic cell types
Plasmacytoid dendritic cell heterogeneity is defined by CXCL10 expression following TLR7 stimulation.
Specimen part, Cell line, Subject
View SamplesBackground. Cellular senescence is a mechanism that virtually irreversibly suppresses the proliferative capacity of cells in response to various stress signals. This includes the expression of activated oncogenes, which cause Oncogene-Induced Senescence (OIS). A body of evidence points to the involvement of chromatin reorganization, including the formation of senescence-associated heterochromatic foci (SAHF). The nuclear lamina (NL) is an important contributor to genome organization and has been involved in cellular senescence and organismal aging. It interacts with multiple regions of the genome called lamina-associated domains (LADs). Some LADs are cell type-specific, while others are conserved between cell types and are referred to as constitutive LADs. Here, we used DamID to investigate the changes in genome-NL interactions in a model of OIS triggered by the expression of the BRAFV600E oncogene.Results. We found that OIS cells lose most of their constitutive LADs (cLADS), suggesting the loss of a specific mechanism that targets cLADs to the NL. In addition, multiple genes relocated to the NL. Unexpectedly, they were not repressed, implying the abrogation of the repressive activity of the NL during OIS. Finally, OIS cells displayed an increased association of telomeres with the NL.Conclusions. Our study reveals that senescent cells acquire a new type of LAD organization and suggest the existence of as yet unknown mechanisms that tether cLADs to the NL and repress gene expression at the NL.
Massive reshaping of genome-nuclear lamina interactions during oncogene-induced senescence.
Specimen part, Cell line, Subject, Time
View SamplesSmoking-induced lung disease is one of the most prevalent forms of lung disease but also one of the more diverse. Based on the phenotypic diversity caused by the same environmental stress, we hypothesized that smoking may induce changes in lung cell expression of genes that, with specific variants, are causative of monogenic lung disease, i.e., not that smoking induces a phenocopy of a genetic disease, but smoking may subtly modify the expression of genes known to be associated with genetic disorders with distinct lung disease phenotypes. To assess this hypothesis, and based on the knowledge that most smoking-related disease phenotypes start in the small airway epithelium, we asked: are the genes associated with the monogenic lung disorders expressed in the small airway epithelium, and if so, does smoking alter the expression of these genes? To accomplish this, we examined small airway epithelium expression of 92 genes known to be associated with 17 monogenic lung disorders in 230 samples of small airway epithelium (SAE) obtained from healthy nonsmokers and healthy smokers without any clinical evidence of disease. Of the 86 monogenic disorder-related genes we found expressed in the SAE, strikingly, 37 were significantly differentially expressed in normal smokers compared to normal nonsmokers (p<0.05, Benjamini-Hochberg correction for multiple comparisons). The data demonstrates that the effect of smoking on the transcriptome of small airway epithelium includes significantly altered regulation of the genes responsible for known monogenic disorders.
Cigarette Smoking Induces Changes in Airway Epithelial Expression of Genes Associated with Monogenic Lung Disorders.
Sex, Age, Race
View SamplesNIH-3T3 cells were pretreated for 15 min with either DMSO (mock) or cycloheximide followed by addition of either mock, 100 U/ml IFNalpha or 100 U/ml IFNgamma for 1h. During the last 30 min, 500 M 4-thiouridine was added to cell culture medium. Total cellular RNA was isolated using Trizol reagent and nascent RNA was purified as described (Dlken et al. RNA 2008) . Three replicates of nascent RNA were analyzed by Affymetrix Mouse Gene ST 1.0 arrays
Deciphering the modulation of gene expression by type I and II interferons combining 4sU-tagging, translational arrest and in silico promoter analysis.
Cell line
View SamplesQuiescent and dividing hemopoietic stem cells (HSC) display marked differences in their ability to move between the peripheral circulation and the bone marrow. Specifically, long-term engraftment potential predominantly resides in the quiescent HSC subfraction, and G-CSF mobilization results in the preferential accumulation of quiescent HSC in the periphery. In contrast, stem cells from chronic myeloid leukemia (CML) patients display a constitutive presence in the circulation. To understand the molecular basis for this, we have used microarray technology to analyze the transcriptional differences between dividing and quiescent, normal, and CML-derived CD34+ cells.
Transcriptional analysis of quiescent and proliferating CD34+ human hemopoietic cells from normal and chronic myeloid leukemia sources.
Specimen part, Disease, Subject
View SamplesWe have sequenced using single end and paired end sequencing GMPs, CMPs, EoPs, SiglecF+IL5ra- GMPs and eosinophils to be able to characterise this new subset of GMPs and to be able to give it some context within a lineage trajectory analysis Overall design: RNA-seq was performed on GMPs (n=2), CMPs (n=2), EoPs (n=2), Eosinophils (n=3) and SiglecF+IL5ra- GMPs isolated from C57BL/6 (n=5) and Myb hypomorphic Plt4/Plt4 mice (n=4).
Identification of a Siglec-F+ granulocyte-macrophage progenitor.
Specimen part, Cell line, Subject
View SamplesIn order to identify the gene targets of frequently altered chromosomal regions in retinoblastoma, a meta-analysis of genome-wide copy number alterations studies on primary retinoblastoma tissue and retinoblastoma cell lines was performed. Published studies were complemented by copy number and gene expression analysis on primary and cell line samples of retinoblastoma. This dataset includes the gene expression data of the retinoblastoma cell lines
A Meta-Analysis of Retinoblastoma Copy Numbers Refines the List of Possible Driver Genes Involved in Tumor Progression.
Specimen part, Cell line
View SamplesWe have analysed a family with an autosomal recessive type of tetraplegic cerebral palsy with mental retardation, reduction of cerebral white matter, and atrophy of the cerebellum in an inbred sibship.
Mutation in the AP4M1 gene provides a model for neuroaxonal injury in cerebral palsy.
Sex, Specimen part
View Samples