Dysregulation of professional APC has been postulated as a major mechanism underlying Ag-specific T cell hyporesponsiveness in patients with patent filarial infection. To address the nature of this dysregulation, dendritic cells (DC) and macrophages generated from elutriated monocytes were exposed to live microfilariae (mf), the parasite stage that circulates in blood and is responsible for most immune dysregulation in filarial infections. DC exposed to mf for 2496 h showed a marked increase in cell death and caspase-positive cells compared with unexposed DC, while mf exposure did not induce apoptosis in macrophages. Interestingly, 48 h exposure of DC to mf induced mRNA expression of the pro-apoptotic gene TRAIL and both mRNA and protein expression of TNF-alpha. mAb to TRAIL-R2, TNF-R1, or TNF-alpha partially reversed mf-induced cell death in DC, as did knocking down the receptor for TRAIL-R2 using small interfering RNA. Mf also induced gene expression of BH3-interacting domain death agonist (Bid) and protein expression of cytochrome c in DC; mf-induced cleavage of Bid could be shown to induce release of cytochrome c, leading to activation of caspase 9. Our data suggest that mf induce DC apoptosis in a TRAIL- and TNF-alpha-dependent fashion.
Induction of TRAIL- and TNF-alpha-dependent apoptosis in human monocyte-derived dendritic cells by microfilariae of Brugia malayi.
Sex, Treatment, Race
View SamplesNeutrophil lysis after phagocytosis is a process potentially important in the pathogenesis of community-associated methicillin-resistant S. aureus (CA-MRSA) infection. The mechanism for this process is not currently known. Therefore, to better understand CA-MRSA virulence we used human oligonucleotide microarrays to investigate the mechanism underlying enhanced PMN lysis that occurs after phagocytosis of CA-MRSA.
Rapid neutrophil destruction following phagocytosis of Staphylococcus aureus.
Specimen part, Treatment
View SamplesSmall RNAs (sRNAs) are hypothesized to contribute to hybrid vigor because they maintain genome integrity, contribute to genetic diversity, and control gene expression. We used Illumina sequencing to assess how sRNA populations vary between two maize inbred lines (B73, Mo17) and their hybrid. We sampled sRNAs from the seedling shoot apex and the developing ear, two rapidly growing tissues that program the greater growth of maize hybrids. We found that parental differences in siRNAs primarily originate from repeat regions. Although the maize genome contains greater number and complexity of repeats compared to Arabidopsis or rice, we confirmed that like these simpler plant genomes, 24-nt siRNAs whose abundance differs between maize parents also show a trend of downregulation following hybridization. Surprisingly, hybrid vigor is fully maintained when 24-nt siRNAs are globally reduced by mutation of the RNA-dependent RNA polymerase2 (RDR2) encoded by modifier of paramutation1 (mop1). We also discovered that 21-22nt siRNAs derived from a number of distinct retrotransposon families differentially accumulate between B73 and Mo17 as well as their hybrid. Thus, maize possesses a novel source of genetic variation for regulating both transposons and genes at a genomic scale, which may contribute to its high degree of observed heterosis. Overall design: sRNA libraries were derived from RNA isolated from the seedling shoot apex and developing ear tissues from B73, Mo17, B73xMo17 and Mo17xB73. The shoot apex was chosen because it is enriched for meristematic tissue where cell proliferation occurs, rates of organ initiation are determined, and organ size is specified. The developing ear was examined because it is enriched in meristematic tissue and is undergoing rapid growth, and also because the mature ear shows the highest degree of heterosis. Total RNA was isolated and separated on a 15% TBE-Urea polyacrylamide gel. Using a 10-bp ladder, the sRNA fraction representing 10-40-bp was excised. sRNA libraries were prepared according to Lu et al. (2007) or manufacturer''s instructitions (Illumina). A combination of Perl scripts and FASTX toolkit scripts were used to remove adapters, collapse identical sequences and count reads per sequence. Supplementary processed data text files contain the distinct sRNA sequences for all of the genotypes analyzed in that experiment. Abundance (reads per million) was calculated for each distinct sequence by dividing the number of reads of distinct sRNA in a library by the total number of sRNA reads for that library and multiplying this by 1 million. Genome builds: B73 genome, maizesequence.org release 4a.53 (October, 2009); Mo17 whole genome shotgun clones.
Repeat associated small RNAs vary among parents and following hybridization in maize.
Specimen part, Subject
View SamplesWe profiled spinal cord tissue at the site of a moderate contusion injury at the level of the thoracic spinal cord
TrkB.T1 contributes to neuropathic pain after spinal cord injury through regulation of cell cycle pathways.
Age, Specimen part, Time
View SamplesRNA expression was measured by RNA-seq in Drosophila ML-DmBG3-c2 cells depleted for proteins involved in sister chromatid cohesion, and in developing third instar wing discs with or withough brca2 gene mutations Overall design: RNA expression in depleted cells was compared to mock treated cells and RNA expression in wing discs from brca2 mutant Drosophila was compared to expression in wing discs without brca2 mutations This series includes mock RNAi treated samples re-used from GSE100547.
Brca2, Pds5 and Wapl differentially control cohesin chromosome association and function.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Identification of the receptor tyrosine kinase AXL in breast cancer as a target for the human miR-34a microRNA.
Cell line
View SamplesThe receptor-interacting protein-associated ICH-1/CED-3 homologous protein with a death domain (Raidd) functions as a dual adaptor protein due to its bipartite nature, and is therefore thought to be a constituent of different multiprotein complexes including the PIDDosome, where it connects the cell death-related protease, Caspase-2, with the p53-induced protein with a death domain 1 (Pidd1). As such, Raidd has been implicated in DNA-damage-induced apoptosis as well as in tumor suppression, the latter based on its role as a direct activator of Caspase-2, known to delay lymphomagenesis caused by overexpression of c-Myc or loss of ATM kinase. As loss of Caspase-2 leads to an acceleration of tumor onset in the E-Myc mouse model we set out to interrogate the role of Raidd in this process in more detail. Our data obtained analyzing E-Myc/Raidd-/- mice indicate that Raidd is unable to protect from c-MYC-driven lymphomagenesis. Similarly, we failed to observe an effect of Raidd-deficiency on thymic lymphomagenesis induced by y-irradiation or fibrosarcoma development driven by 3-methylcholanthrene. The role of Caspase-2 as a tumor suppressor can therefore be uncoupled from its ability to interact and auto-activate upon binding to Raidd. Further, we provide supportive evidence that the tumor suppressive role of Caspase-2 is related to maintaining genomic integrity and allowing efficient p53-mediated signaling. Overall, our findings suggest that Raidd, although described to be the key-adapter allowing activation of the tumor suppressor Caspase-2, fails to suppress tumorigenesis in vivo.
The tumor-modulatory effects of Caspase-2 and Pidd1 do not require the scaffold protein Raidd.
No sample metadata fields
View SamplesRNA expression was measured using RNA-seq Overall design: RNA levels in Mock-treated control Drosophila cells were compared to RNA levels in cells RNAi depleted for Ph, Sce, and Pc
Polycomb repressive complex 1 modifies transcription of active genes.
Subject
View SamplesRNA nascent transcription was measured using NT-seq Overall design: RNA nascent transcript levels in Mock-treated control Drosophila cells were compared to those in cells RNAi depleted for Ph and Sce
Polycomb repressive complex 1 modifies transcription of active genes.
Subject
View SamplesTriple negative breast cancer (TNBC) is histologically characterized by the absence of the hormone receptors estrogen and progesterone, in addition to having a negative immunostain for HER-2. The aggressiveness of this disease and lack of targeted therapeutic options for treatment is of high clinical importance. MicroRNAs are short 21- to 23 nucleotide endogenous non-coding RNAs that regulate gene expression by binding to mRNA transcripts, resulting in either decreased protein translation or mRNA degradation. Dysregulated expression of miRNAs is now a hallmark of many human cancers. In order to identify a miRNA/mRNA interaction that is biologically relevant to the triple negative breast cancer genotype/phenotype, we initially conducted a miRNA profiling experiment to detect differentially expressed miRNAs in cell line models representing the triple negative (MDA-MB-231), ER+ (MCF7), and HER-2 overexpressed (SK-BR-3) histotypes. We identified human miR-34a expression as being >3-fold down (from its median expression value across all cell lines) in MDA-MB-231 cells, and identified AXL as a putative mRNA target using multiple miRNA/target prediction algorithms. The miR-34a/AXL interaction was functionally characterized through ectopic overexpression experiments with a miR-34a mimic. In reporter assays, miR-34a binds to the putative target site within the AXL 3UTR to affect luciferase expression. We also observed degradation of AXL mRNA and decreased AXL protein levels, as well as cell signaling effects on AKT phosphorylation and phenotypic effects on cell migration. Finally, we present an inverse correlative trend in miR-34a and AXL expression for both cell line and patient tumor samples.
Identification of the receptor tyrosine kinase AXL in breast cancer as a target for the human miR-34a microRNA.
Cell line
View Samples