Nutrient-responsive oogenesis in Drosophila is a complex and dynamic process regulated, in part, by members of the Pc and Trx complexes. The recent finding that O-GlcNAc Transferase (ogt/sxc) is essential for Pc repression raises the question of whether this nutrient-sensing pathway plays a role in regulating oogenesis. OGT transfers O-GlcNAc to key transcriptional regulators in response to graded levels of the nutrient-derived precursor UDP-GlcNAc; O-GlcNAcase (OGA) catalyzes the removal of O-GlcNAc. Here we produced a null allele of oga (oga1) in Drosophila to examine its in vivo function. We found that oga mutant flies were viable, but that females displayed greatly reduced fecundity. The ovaries from the female OGA knockout exhibited a starvation-like phenotype, even under well-fed conditions. Germline stem cell division was slowed in the germarium of OGA knockout fly ovarioles. Ovaries from the oga1 mutants displayed significantly decreased H3K4 monomethylation in germline stem cells. The Trithorax family members Trx and Ash1 and Compass member Set1 histone methyltransferases are O-GlcNAc modified in oga1 mutant ovaries. Our results suggest that the loss of OGA disrupts oogenesis at least in part by interfering with H3K4 monomethylation in germ cells in the ovary. The findings also suggest that O-GlcNAc cycling is an essential part of the nutrient-responsive epigenetic machinery regulating Drosophila oogenesis in response to a changing nutrient supply.
Drosophila O-GlcNAcase Deletion Globally Perturbs Chromatin O-GlcNAcylation.
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View SamplesWe extracted RNA from whole cells and RNA from the cytoplasm and performed RNA sequening to compare differences in gene expression level and investigate what is the most appropriate estimate of the amount of mRNA present in a given cell population. The study was based on three human cell lines. Overall design: Analyze of transcriptome in 3 human cell lines (U-2 OS, A-431, U-251MG). Each cell line was prepared with four biological replicates for total RNA and four for cytoplasmic RNA.
Comparison of total and cytoplasmic mRNA reveals global regulation by nuclear retention and miRNAs.
No sample metadata fields
View SamplesAge-dependent electrical and morphological remodeling of the Drosophila heart caused by hERG/seizure mutations
Age-dependent electrical and morphological remodeling of the Drosophila heart caused by hERG/seizure mutations.
No sample metadata fields
View SamplesPaired-end sequencing of Vector and H-Ras expressing cell lines: p53-del and WT-p53 We found that activated forms of H-Ras and PIK3CA oncogene lead to repression of p63, a p53 family member. They also lead to induction of EMT, a cancer-related process. Our results suggest that, through Ras regulation of p63, this oncogene can drive mammary epithelial cells towards greater invasive ability. Overall design: 4 samples analyzed with 3 replicates each, control samples for each H-Ras line are the Vector cell line created at the same time
Repression of p63 and induction of EMT by mutant Ras in mammary epithelial cells.
Cell line, Subject
View SamplesCellular differentiation is regulated through activation and repression of defined transcription factors. A hallmark of differentiation is a pronounced change in cell shape, which is determined by dynamics of the actin cytoskeleton. In de-differentiated fat (DFAT) cells and 3T3-L1 cells, we showed that treatment with the ROCK inhibitor Y-27632, by inducing remodeling of the actin cytoskelton, causes adipocyte differentiation. In addition, we found that depletion of MKL1, an actin binding transcriptional coactivator, elicits adipogenesis.
Regulation of MKL1 via actin cytoskeleton dynamics drives adipocyte differentiation.
Specimen part
View SamplesProliferative diabetic retinopathy (PDR) is a vision-threatening disorder characterized by the formation of cicatricial fibrovascular membranes leading to traction retinal detachment. Despite the recent advance in the treatment of PDR such as vitreoretinal surgery with use of anti-vascular endothelial growth factor (VEGF) drug as an adjunct, it still remains vision-threatening disease.
Microarray analysis of gene expression in fibrovascular membranes excised from patients with proliferative diabetic retinopathy.
Specimen part, Disease, Disease stage
View SamplesSome neuropsychiatric disease, including schizophrenia, may originate during prenatal development, following periods of gestational hypoxia and placental oxidative stress. Here we investigated if gestational hypoxia promotes damaging secretions from the placenta that affect fetal development and whether a mitochondria-targeted antioxidant MitoQ might prevent this. Gestational hypoxia caused low birth-weight and changes in young adult offspring brain, mimicking those in human neuropsychiatric disease. Exposure of cultured neurons to fetal plasma or to secretions from the placenta or from model trophoblast barriers that had been exposed to altered oxygenation caused similar morphological changes. The secretions and plasma contained altered microRNAs whose targets were linked with changes in gene expression in the fetal brain and with human schizophrenia loci. Molecular and morphological changes in vivo and in vitro were prevented by a single dose of MitoQ bound to nanoparticles, which were shown to localise and prevent oxidative stress in the placenta but not in the fetus. We suggest the possibility of developing preventative treatments that target the placenta and not the fetus to reduce risk of psychiatric disease in later life. Overall design: 16 samples (4 biological replicates per group) were analysed using RNA sequencing. The 4 groups were: Normoxia+Saline (control sample), Normoxia+MitoQ-NP, Hypoxia+Saline and Hypoxia+MitoQ-NPs. Pair-wise comparison between all groups was performed.
Treating the placenta to prevent adverse effects of gestational hypoxia on fetal brain development.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
PU.1 is a potent tumor suppressor in classical Hodgkin lymphoma cells.
Cell line, Time
View SamplesPU.1 is an Ets family transcription factor that is essential for the differentiation of both myeloid and lymphoid cells. PU.1 is down-regulated in classical Hodgkin lymphoma cells via methylation of the PU.1 promoter. To evaluate whether down-regulation of PU.1 is essential for the growth of cHL cells, we generated KM-H2 derived cell lines conditionally express PU.1 by tet-off system (designated KM-H2tetPU.1). Conditonally expressed PU.1 by tetracycline removal induced complete growth arrest and apoptosis in KM-H2 cells. To elucidate the mechanisms underlying cell cycle arrest and apoptosis induced by PU.1, we compared gene expression profiles of KM-H2tetPU.1 cells 0, 1 and 3 days after PU.1 induction, by DNA microarray.
PU.1 is a potent tumor suppressor in classical Hodgkin lymphoma cells.
Cell line, Time
View SamplesDiscrimination between self vs. non-self and adequate response to infection and tissue damage are fundamental functions of the immune system. The rapid and global spread of known and emerging viruses is a testament that the timely detection of viral pathogens that reproduce within host cells, presents a formidable challenge to the immune system. To gain access to a proper reproductive niche, many pathogens travel via the host vasculature and therefore become exposed to humoral factors of the innate immune system. Although a cascade of coagulation factors plays a fundamental role in host defense for living fossils such as horseshoe crabs (Xiphosurida spp), the role of the coagulation system in activation of innate responses to pathogens in higher organisms remains unclear. When human type C adenovirus (HAdv) enters the circulation, 240 copies of coagulation factor X (FX) bind to the virus particle with picomolar affinity. Here, using molecular dynamics flexible fitting (MDFF) and high resolution cryo-electron microscopy (cryo-EM), we defined the interface between the HAdv5 hexon protein and FX at pseudo-atomic level. Based on this structural data, we introduced a single amino acid substitution, T424A, in the hexon that completely abrogated FX interaction with the virus. In vivo genome-wide transcriptional profiling revealed that FX-binding-ablated virus failed to activate a distinct network of the early response genes, whose expression depends on transcription factor NFKB1. Deconvolution of the signaling network responsible for early gene activation showed that the FX-HAdv complex triggers MyD88/TRIF/TRAF6 signaling upon activation of toll-like receptor 4 (TLR4) that serves as a principal sensor of FX-virus complex in vivo. Our study implicates host factor decoration of the virus as a mechanism to trigger innate immune sensor that respond to a misplacement of coagulation FX from the blood into intracellular macrophage compartments upon virus entry into the cell. Our results further the mounting evidence of evolutionary conservation between the coagulation system and innate immunity.
Coagulation factor X activates innate immunity to human species C adenovirus.
Specimen part, Treatment
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