Type 1 diabetes (T1D) is caused by autoimmune destruction of pancreatic ß cells. Mounting evidence supports a central role for ß-cell alterations in triggering the activation of self-reactive T-cells in T1D. However, the early deleterious events that occur in ß cells, underpinning islet autoimmunity are not known. We hypothesized that epigenetic modifications induced in ß cells by inflammatory mediators play a key role in initiating the autoimmune response. We analyzed DNA methylation (DNAm) patterns and gene expression in human islets exposed to IFNa, a cytokine associated with T1D development. We found that IFNa triggers DNA demethylation and increases expression of genes controlling inflammatory and immune pathways. We then demonstrated that DNA demethylation was caused by up-regulation of the exoribonuclease, PNPase Old-35 (PNPT1), which caused degradation of miR-26a. This in turn promoted the up-regulation of ten-eleven translocation TET2 enzyme and increased 5-hydoxymethylcytosine levels in human islets and pancreatic ß-cells. Moreover, we showed that specific IFNa expression in the ß cells of IFNa-INS1CreERT2 transgenic mice, led to development of T1D that was preceded by increased islet DNA hydroxymethylation through a PNPT1/TET2-dependent mechanism. Our results suggest a new mechanism through which IFNa regulates DNAm in ß cells, leading to changes in expression of genes in inflammatory and immune pathways that can initiate islet autoimmunity in T1D. Overall design: We exposed human pancreatic islets from three donors to 2000 IU IFNa and assessed gene expression by RNAseq. The cDNA library was prepared using Illumina TruSeq RNA Sample Prep Kits. Next generation sequencing was performed on Illumina HiSeq2000 using the Single-Read Cluster Generation kit v2 and SBS Sequencing kit v3. Image analysis and base calling were conducted using the SDS 2.5/RTA1.5 software.
Epigenetic modulation of β cells by interferon-α via PNPT1/mir-26a/TET2 triggers autoimmune diabetes.
Specimen part, Disease stage, Treatment, Subject
View SamplesPromoter hypermethylation and transcriptional silencing is a common epigenetic mechanism of tumour suppressor inactivation in cancer, including malignant brain tumours.
Epigenetic genome-wide analysis identifies BEX1 as a candidate tumour suppressor gene in paediatric intracranial ependymoma.
Specimen part, Treatment
View SamplesPurpose: The goal of this study is to analyze the transcriptional pathways regulated by Fbxo22 and Keap1 in mouse lung adeno carcinoma cells. Methods: mouse lung adeno carcinoma cells either Keap1 wild type (KP) or mutant (KPK), have been transfected for 3 days with siRNA targeting Fbxo22. Knock down efficiency has been evaluated by western blot (using specific antibody for Fbxo22) and qPCR (using specific oligos for Fbxo22) . Results: The transcriptomic analysis helps us to support our finding that loss of either Keap1 or Fbxo22 induces metastases Overall design: All 12 samples generated by deep sequencing in triplicate
Nrf2 Activation Promotes Lung Cancer Metastasis by Inhibiting the Degradation of Bach1.
Specimen part, Subject
View SamplesParathyroid hormone (PTH) plays an essential role in regulating calcium and bone homeostasis in the adult, but whether PTH is required at all for regulating fetal-placental mineral homeostasis is uncertain. To address this we treated Pth-null mice in utero with 1 nmol PTH (1-84) or saline and examined placental calcium transfer 90 minutes later. It was found that placental calcium transfer increased in Pth-null fetuses treated with PTH as compared to Pth-null fetuses treated with saline. Subsequently, to determine the effect of PTH treatment on placental gene expression, in a separate experiment, 90 minutes after the fetal injections the placentas were removed for subsequent RNA extraction and microarray analysis.
Parathyroid hormone regulates fetal-placental mineral homeostasis.
Sex, Specimen part, Treatment
View SamplesExpression was generated on tumors from 41 iBIP mice, which were previously described (Kwong, JCI, 2015).
Oncogenic BRAF-Mediated Melanoma Cell Invasion.
Specimen part
View SamplesWe report high-throughput profiling of gene expression from whole zebrafish ventricles. We profile mRNA in uninjured ventricles and those undergoing regeneration 14 days after genetic ablation. This study provides a framework for understanding transcriptional changes during adult models of regeneration. Overall design: Examination of gene expression in cardiomyocytes under different states of proliferation.
Resolving Heart Regeneration by Replacement Histone Profiling.
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View SamplesWe used microarrays to identify transcripts regulated by dexamethasone in omental (Om) and abdominal subcutaneous (Abdsc) adipose tissues of severely obese females obtained during elective surgeries.
Depot Dependent Effects of Dexamethasone on Gene Expression in Human Omental and Abdominal Subcutaneous Adipose Tissues from Obese Women.
Specimen part, Disease stage, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNA-Offset RNA Alters Gene Expression and Cell Proliferation.
Specimen part, Treatment
View SamplesMammalian insulin and IGF induce similar but not identical changes in gene expression downstream of their respective receptors. Signaling bias at the receptor differentiates the two similar ligands, though the precise mechanism is not entirely understood. We used Drosophila insulin-like peptides DILP2 and DILP5 to determine how similar insulin-like ligands regulate similar and distinct patterns of gene expression in S2 cells by RNA-Seq. Overall, DILP2 and DILP5 stimulate many of the same changes in gene expression. However, some genes are uniquely regulated by DILP2 or by DILP5. Shared and distinct gene targets were validated by q-RT-PCR with indepedent replicates. Some unique gene targets of DILP2 are involved in sugar metabolism, which is functionally related in vivo to DILP2 and not DILP5. We find that gene expression is largely regulated in parallel by DILP2 and DILP5 but some key unique targets may lead to differential physiological functions for the two insulin-like genes. Overall design: mRNA profiles from S2 cells treated with DILP2, DILP5 or solvent were sequenced on an Illumina HiSeq2500
<i>Drosophila</i> Insulin-Like Peptides DILP2 and DILP5 Differentially Stimulate Cell Signaling and Glycogen Phosphorylase to Regulate Longevity.
Cell line, Treatment, Subject
View SamplesMicroRNA-offset RNAs (moRs) were first identified in simple chordates and subsequently in mouse and human cells by deep sequencing of short RNAs. MoRs are derived from sequences located immediately adjacent to microRNAs (miRs) in the primary miR (pri-miR). Currently moRs are considered to be simply a by-product of miR biosynthesis that lack biological activity. Here we show for the first time that a moR is biologically active. We now demonstrate that endogenous and over-expressed moR-21 significantly alters gene expression and inhibits the proliferation of vascular smooth muscle cells (VSMC). We report that the seed region of moR-21 as well as the seed match region in the target gene 3'UTR are indispensable for moR-21-mediated gene down-regulation. We further demonstrated that moR-21-mediated gene repression is Argonaute 2 (Ago2) dependent. In addition, we find that miR-21 and moR-21 may regulate different genes in a given pathway and can oppose each other in regulating certain genes. Taken together, these findings provide the first evidence that microRNA offset RNA regulates gene expression and is biologically active.
MicroRNA-Offset RNA Alters Gene Expression and Cell Proliferation.
Specimen part, Treatment
View Samples