This SuperSeries is composed of the SubSeries listed below.
Dnmt3L antagonizes DNA methylation at bivalent promoters and favors DNA methylation at gene bodies in ESCs.
Specimen part, Cell line
View SamplesThe de novo DNA methyltransferase 3-like (Dnmt3L) is a catalytically inactive DNA methylase that has been previously shown to cooperate with Dnmt3a and Dnmt3b to methylate DNA. Dnmt3L is highly expressed in mouse embryonic stem cells (ESC) but its function in these cells is unknown. We here report that Dnmt3L is required for the differentiation of ESC into primordial germ cells (PGC) through activation of the homeotic gene Rhox5. By genome-wide analysis we found that Dnmt3L is a positive regulator of methylation at gene bodies of housekeeping genes and a negative regulator of methylation at promoters of bivalent genes. We demonstrate that Dnmt3L interacts with the Polycomb PRC2 complex in competition with the DNA methyl transferases Dnmt3a and Dnmt3b to maintain low the methylation level at H3H27me3 regions. Thus in ESC, Dnmt3L counteracts the activity of de novo DNA methylases to keep low the level of DNA methylation at developmental gene promoters.
Dnmt3L antagonizes DNA methylation at bivalent promoters and favors DNA methylation at gene bodies in ESCs.
Specimen part
View SamplesEmbryonic stem cells (ESCs) cells run a self-renewal gene expression program, requiring the expression of certain transcription factors accompanied by a particular chromosome organization to maintain a balance between pluripotency and the capacity for rapid differentiation. However, how transcriptional regulation is linked to chromosome organization in ESCs remains enigmatic. Here we show that Cohesin exhibits a functional role in maintaining ESC identity through association with the pluripotency transcriptional network. ChIP-seq analyses of the cohesin subunit Rad21 reveal an ESC specific cohesin binding pattern that is characterized by a CTCF independent colocalization of cohesin with pluripotency related transcription factors. Upon ESC differentiation, these binding sites disappear and instead new CTCF independent Rad21 binding sites emerge, which are enriched for binding sites of transcription factors implicated in early differentiation. Furthermore, knock-down of cohesin subunits causes expression changes that are reminiscent of the depletion of key pluripotency transcription factors, demonstrating the functional relevance of the cohesin - pluripotency transcriptional network association. Finally, we show that Nanog physically interacts with the cohesin interacting proteins Stag1 and Wapl, further substantiating this association. Based on these findings we propose that a dynamic placement of cohesin by pluripotency transcription factors contributes to a chromosome organization supporting the ESC expression program.
RAD21 cooperates with pluripotency transcription factors in the maintenance of embryonic stem cell identity.
Specimen part
View SamplesFK1706 potentiated nerve growth factor-induced neurite outgrowth, putatively mediated via FKBP-52 and the Ras/Raf/MAPK signaling pathway. It also improved mechanical allodynia accompanied by the recovery of intraepidermal nerve fiber density in a painful diabetic neuropathy in rats.
FK1706, a novel non-immunosuppressive immunophilin ligand, modifies gene expression in the dorsal root ganglia during painful diabetic neuropathy.
Specimen part, Treatment
View Sampleswe evaluated the modulation of gene expression profile in PBMCs from patients with hypotalamic amenorrhea. We have employed whole genome microarray expression profiling as a discovery platform to identify genes differentially expressed upon metreleptin treatment at different time points, week 12, 24 and 36.
Selective capacity of metreleptin administration to reconstitute CD4+ T-cell number in females with acquired hypoleptinemia.
Treatment, Subject
View SamplesScope: As a result of population ageing, the number of Alzheimer’s disease (AD) patients has rapidly increased. There are many hypothesises on the pathogenesis of AD, but its detailed molecular mechanism is still unknown, and so no effective preventive or therapeutic measures have been established. Some reports showed a decrease in levels of norepinephrine (NE) has been suspected to be involved in the decline of cognitive function in AD patients and NE concentrations were decreased in postmortem AD patient brains. Tyr-Trp was identified as being the most effective dipeptide in enhancing norepinephrine (NE) synthesis and metabolism. And Tyr-Trp treatment ameliorated the short-term memory dysfunction in AD model mice caused by amyloid beta (Aβ) 25-35. So, the purpose of this study was to investigate the preventive or/and protective effects of Tyr-Trp administration in AD model mice.
Tyr-Trp administration facilitates brain norepinephrine metabolism and ameliorates a short-term memory deficit in a mouse model of Alzheimer's disease.
Specimen part
View SamplesThe mouse anterior-posterior (A-P) axis polarization is preceded by formation of the distal visceral endoderm (DVE). However, the mechanism of the emergence of DVE cells is not well understood. Here, we show by in vitro culturing of embryos immediately after implantation in micro-fabricated cavities (narrow; 90 micro-meter, wide; 180 miro-meter in diameter) that the external mechanical cues exerted on the embryo, i.e. cultured in the narrow cavity, are crucial for DVE formation as well as elongated egg cylinder shape. This implies that these developmental events immediately after implantation are not simply embryo-autonomous processes but require extrinsic mechanical factors. Further whole genome-wide gene expression profiles with DNA microarray revealed that no significant difference of transcripts were evident with or without mechanical cues except DVE-related markers. Thus, we propose that external mechanical cues rather than not specific molecular pathways can trigger the establishment of the A-P axis polarization, which is one of the fundamental proccesses of mammalian embryogenesis.
External mechanical cues trigger the establishment of the anterior-posterior axis in early mouse embryos.
Specimen part, Treatment
View SamplesOvarian clear cell carcinoma (OCCC) shows unique clinical features including an association with endometriosis and poor prognosis. We previously reported that the contents of endometriotic cysts, especially high concentrations of free iron, are a possible cause of OCCC carcinogenesis through iron-induced persistent oxidative stress. In this study, we conducted gene expression microarray analysis using 38 ovarian cancer cell lines and identified genes commonly expressed in both OCCC cell lines and clinical samples, which comprise an OCCC gene signature. The OCCC signature reproducibly predicts OCCC specimens in other microarray data sets, suggesting that this gene profile reflects the inherent biological characteristics of OCCC. The OCCC signature contains known markers of OCCC, such as hepatocyte nuclear factor-1b (HNF-1b) and versican (VCAN), and other genes that reflect oxidative stress. Expression of OCCC signature genes was induced by treatment of immortalized ovarian surface epithelial cells with the contents of endometriotic cysts, indicating that the OCCC signature is largely dependent on the tumor microenvironment. Induction of OCCC signature genes is at least in part epigenetically regulated, as we found hypomethylation of HNF-1b and VCAN in OCCC cell lines. This genomewide study indicates that the tumor microenvironment induces specific gene expression profiles that contribute to the development of distinct cancer subtypes.
Identification of an ovarian clear cell carcinoma gene signature that reflects inherent disease biology and the carcinogenic processes.
Sex, Specimen part, Cell line, Treatment
View SamplesIn order to investigate the effects of Glatiramer acetate (GA) in treatment-nave RR-MS female patients B cells we performed Affymetrix Gene-Chip Human Genome HG-U133A_2 hybridization experiments
Glatiramer Acetate modulates ion channels expression and calcium homeostasis in B cell of patients with relapsing-remitting multiple sclerosis.
Sex, Specimen part, Disease, Subject
View SamplesDietary restriction extends lifespan and delays the age-related physiological decline in many species. Intermittent fasting (IF) is one of the most effective dietary restriction regimens that extends lifespan in C. elegans and mammals1,2. In C. elegans, the FOXO transcription factor DAF-16 is implicated in fasting-induced gene expression changes and the longevity response to IF3; however, the mechanisms that sense and transduce fasting-stress stimuli have remained largely unknown. Here we show that a KGB-1/AP1 (activator protein 1) module is a key signalling pathway that mediates fasting-induced transcriptional changes and IF-induced longevity. Our promoter analysis coupled to genome-wide microarray results has shown that the AP-1-binding site, together with the FOXO-binding site, is highly over-represented in the promoter regions of fasting-induced genes. We find that JUN-1 (C. elegans c-Jun) and FOS-1 (C. elegans c-Fos), which constitute the AP-1 transcription factor complex, are required for IF-induced longevity. We also find that KGB-1 acts as a direct activator of JUN-1 and FOS-1, is activated in response to fasting, and, among the three C. elegans JNKs, is specifically required for IF-induced longevity. Our results demonstrate that most fasting-induced upregulated genes, including almost all of the DAF-16-dependent genes, require KGB-1 and JUN-1 function for their induction, and that the loss of kgb-1 suppresses the fasting-induced upregulation of DAF-16 target genes without affecting fasting-induced DAF-16 nuclear translocation. These findings identify the evolutionarily conserved JNK/AP-1 module as a key mediator of fasting-stress responses, and suggest a model in which two fasting-induced signalling pathways leading to DAF-16 nuclear translocation and KGB-1/AP-1 activation, respectively, integrate in the nucleus to coordinately mediate fasting-induced transcriptional changes and IF-induced longevity.
A fasting-responsive signaling pathway that extends life span in C. elegans.
Treatment
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