Plasmacytoid dendritic cells (pDC) are the major source of type I interferons (IFN-I) during viral infections, in response to triggering of endosomal Toll Like Receptors (TLR) 7 or 9 by viral single-stranded RNA or unmethylated CpG DNA, respectively. IFN-I production in pDC occurs in specialized endosomes encompassing preformed signaling complexes of TLR7 or 9 with their adaptor molecule MyD88 and the transcription factor interferon regulatory factor 7 (IRF7). The triggering of TLR leads to IRF7 phosphorylation, nuclear translocation and binding to the promoters of the genes encoding IFN-I to initiate their transcription. pDC express uniquely high levels of IRF7 at steady state and this expression is further enhanced by positive IFN-I feedback signaling during viral infections. However, the specific cell-intrinsic roles of MyD88 versus IFN-I signaling in pDC responses to a viral infection have not been rigorously dissected. To achieve this aim, we generated mixed bone marrow chimera mice (MBMC) allowing to rigorously compare the gene expression profiles of WT versus Ifnar1-KO or MyD88-KO pDC isolated from the same animals at steady state or after infection with the mouse cytomegalovirus (MCMV). Our results indicate that, in vivo during MCMV infection, pDC undergo a major transcriptional reprogramming, under combined instruction of IFN-I, IFN- and direct TLR triggering. However, these different stimuli drive specific, largely distinct, gene expression programs. We rigorously determined which gene modules require cell-intrinsic IFN-I signaling for their induction in pDC during a physiological viral infection in vivo. We delineated non-redundant versus shared versus antagonistic responses with IFN-. We demonstrated that cell-intrinsic IFN-I responsiveness is dispensable for induction of the expression of all IFN-I/III genes and many cytokines or chemokines in pDC during MCMV infection, contrary to MyD88 signaling.
Molecular dissection of plasmacytoid dendritic cell activation <i>in vivo</i> during a viral infection.
Specimen part, Treatment
View SamplesThe goal of this experiment was to use global gene expression profiling to assess the global genetic reprogramming of different types of splenic mononuclear phagocytes early after MCMV infection in vivo. This study includes new samples (GSM3178486-GSM3178497; available below) profiling splenic CD11b+ conventional dendritic cells (cDC2), classical monocytes (cMo) and red pulp macrophages (RPM) from untreated or day 1.5 MCMV-infected mice together with re-analysis of previously published data in order to examine the similarities in the pDC gene expression profiles across datasets.
Molecular dissection of plasmacytoid dendritic cell activation <i>in vivo</i> during a viral infection.
Specimen part, Treatment
View SamplesHuman mucosal surfaces contain a wide range of microorganisms. The biological effects of these organisms are largely unknown. Large-scale metagenomic sequencing is emerging as a method to identify novel microbes. Unexpectedly, we identified DNA sequences homologous to virus ATCV-1, an algal virus not previously known to infect humans, in oropharyngeal samples obtained from healthy adults. The presence of ATCV-1 was associated with a modest but measurable decrease in cognitive functioning. A relationship between ATCV-1 and cognitive functioning was confirmed in a mouse model, which also indicated that exposure to ATCV-1 resulted in changes in gene expression within the brain. Our study indicates that viruses in the environment not thought to infect humans can have biological effects.
Chlorovirus ATCV-1 is part of the human oropharyngeal virome and is associated with changes in cognitive functions in humans and mice.
Treatment
View SamplesThe autoregulation of mycorrhization (AOM) describes a plant regulatory mechanism that limits the number of infection events by arbuscular mycorrhizal fungi. The key signal mediator is a receptor kinase (GmNARK) that acts in the shoots. Early signals of the mycorrhizal symbiosis induce a root-derived signal that activates GmNARK in the shoot finally leading to a systemic repression of subsequent infections in the root. So far, less is known about the signals down-stream of GmNARK. To find genes regulated by GmNARK in a mycorrhiza-dependent as well as in a mycorrhiza-independent manner, we used the Affymetrix GeneChip for soybean. In general, mycorrhizal root systems consist of both colonized and non-colonized, but autoregulated roots. To physically separate those two root types for transcript analysis of specifically regulated genes, we used the split-root system. Transcript profiling during AOM was done with material of Bragg wild-type and of the nark mutant nts1007, either non-inoculated or partially inoculated with the mycorrhizal fungus Rhizophagus irregularis (formerly Glomus intraradices). Wild-type and nark mutants were inoculated with R. irregularis on one half of the root-systems (root-parts "A") only. The remaining half of the root-systems stayed non-infected (root-parts "B"). Corresponding controls stayed completely non-infected. Gene expression was analyzed in inoculated root-parts, non-inoculated root-parts and shoots of three individual plants per treatment. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Sara Schaarschmidt. The equivalent experiment is GM53 at PLEXdb.]
Analyzing the soybean transcriptome during autoregulation of mycorrhization identifies the transcription factors GmNF-YA1a/b as positive regulators of arbuscular mycorrhization.
Age, Specimen part
View SamplesBackground: Pollen, the male partner in the reproduction of flowering plants, comprises either two or three cells at maturity. The current knowledge of the pollen transcriptome is limited to the model plant Arabidopsis thaliana, which has tri-cellular pollen grains at maturity.
Genomic expression profiling of mature soybean (Glycine max) pollen.
No sample metadata fields
View SamplesOligodendrocyte precursor cells (OPCs) constitute the main proliferative cells in the adult brain, and deregulation of OPC proliferation-differentiation balance results in either glioma formation or defective adaptive (re)myelination. OPC differentiation requires significant genetic reprogramming implicating chromatin remodeling. Mounting evidence indicates that chromatin remodelers play important roles during normal development and their mutations are associated with neurodevelopmental defects, with CHD7 haploinsuficiency being the cause of CHARGE syndrome and CHD8 being one of the strongest Autism Spectrum Disorder (ASD) high-risk associated genes. Here, we report on uncharacterized functions of the chromatin remodelers Chd7 and Chd8 in OPCs. Their OPC-chromatin-binding profile combined with transcriptome and chromatin accessibility analyses of Chd7-deleted OPCs, demonstrates that Chd7 protects non-proliferative OPCs from apoptosis by chromatin-closing and transcriptional repression of p53. Furthermore, Chd7 controls OPC differentiation through chromatin-opening and transcriptional activation of key regulators, including Sox10, Nkx2.2 and Gpr17. Chd7 is however dispensable for oligodendrocyte stage progression, consistent with Chd8 compensatory function, as suggested by their common chromatin binding profiles and genetic interaction. Finally, CHD7 and CHD8 bind in OPCs to a majority of ASD-risk associated genes, suggesting an implication of oligodendrocyte lineage cells in ASD neurological defects. Our results thus offer new avenues to understand and modulate the CHD7 and CHD8 functions in normal development and disease. Overall design: RNA-seq from Chd7iKO and Control O4+ soted cells
Oligodendrocyte precursor survival and differentiation requires chromatin remodeling by Chd7 and Chd8.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNAs establish robustness and adaptability of a critical gene network to regulate progenitor fate decisions during cortical neurogenesis.
Specimen part
View SamplesDuring cortical development neurons are generated sequentially from basal progenitors (BPs) which specifically express the transcription factor Tbr2. We used fluorescent-activaed cell sorting (FACS) to isolate BPs from Tbr2GFP knockin reporter mice (Arnold SJ et al. Genesis, 2009) at early (embryonic day, E13) and late (embryonic day, E16) stages of cortical neurogenesis and determined mRNA expression profiles using mouse mRNA microarray (Illumina MouseWG-6 v2). Comparison of E13 and E16 mRNA expression profiles allowed us to identify regulatory gene networks for maintaining stage specific homeostasis of BPs throughout neurogenesis.
MicroRNAs establish robustness and adaptability of a critical gene network to regulate progenitor fate decisions during cortical neurogenesis.
Specimen part
View SamplesPurpose: Citron kinase (CitK) knockout mice show a severe form of primary microcephaly, associated with ataxia and lethal epilepsy. This phenotype is caused by massive apoptosis occuring during embryonic and post-natal brain development, associated with cytokinesis failure. Cerebellum is the tissue showing highest sensitivity to CitK loss. The clinical phenotype of CitK knockout mice is significantly resued by P53 inactivation. In addition, CitK/P53 double knockout brains have almost normal levels of apoptosis, but display high percentage of binucleated and multinucleated cells. The aim of this study was to analyze the gene expression changes produced in developing neural tissue by CitK loss and to determine which alterations are P53-dependent. expression changes Methods: We analyzed by RNA sequencing total RNA extracted from P4 cerebellum of mice characterized by the following genotypes: 1. CitK +/-, P53 +/- (CTRL); 2. CitK -/-, P53 +/- (CitK-KO); 3. CitK +/-, P53 -/- (P53-KO); 4. CitK -/-, P53 -/- (D-KO). Biological triplicates were analyzed per every genotype. Conclusions: The loss of CitK leads to a strong reduction of the expression of pro-neural genes and induces a P53-related pro-apoptotic gene sets. The analysis of D-KO mice reveals that most of these changes are P53-dependent, but many genes implicated in growth arrest are induced through P53-independent mechanisms. Overall design: Cerebellar mRNA profiles of 4-day old mice of CTRL, CitK-KO, P53-KO and D-KO mice were generated by deep sequencing, in triplicate, using Illumina HiScan SQ
ZIKA virus elicits P53 activation and genotoxic stress in human neural progenitors similar to mutations involved in severe forms of genetic microcephaly.
Specimen part, Cell line, Subject
View SamplesThese data provide scientific information to understand the mechanism of action of lapatinib resistance in HER2-positive patients and to test the combination of HER2-targeted agents and GSK1363089 (foretinib) in the clinic by using an acquired lapatinib-resistant cell line.
Novel mechanism of lapatinib resistance in HER2-positive breast tumor cells: activation of AXL.
Specimen part, Cell line, Treatment
View Samples