Dysfunctional mitochondria and generation of reactive oxygen species (ROS) promote chronic diseases, which have spurred interest in the molecular mechanisms underlying these conditions. Previously, we have demonstrated that disruption of post-translational modification of proteins with ß-linked N-acetylglucosamine (O- glcnAcylation) via overexpression of the O-glcnAc–regulating enzymes O- glcnAc transferase (OGT) or O- glcnAcase (OGA) impairs mitochondrial function. Here, we report that sustained alterations in O- glcnAcylation either by pharmacological or genetic manipulation also alters metabolic function. Sustained O-glcnAc elevation in SH-SY5Y neuroblastoma cells increased OGA expression and reduced cellular respiration and ROS generation. Cells with elevated O-glcnAc levels had elongated mitochondria and increased mitochondrial membrane potential, and RNA-Seq in SH-SY5Y cells indicated transcriptome reprogramming and down regulation of the NRF2-mediated antioxidant response. Sustained O-glcnAcylation in mice brain and liver validated the metabolic phenotypes observed in the cells, and OGT knockdown in the liver elevated ROS levels, impaired respiration, and increased the NRF2 antioxidant response. Moreover, elevated O-glcnAc levels promoted weight loss and lowered respiration in mice and skewed the mice toward carbohydrate-dependent metabolism as determined by indirect calorimetry. In summary, sustained elevation in O-glcnAcylation coupled with increased OGA expression reprograms energy metabolism, a finding that has potential implications for the etiology, development, and management of metabolic diseases. Overall design: SY5Y cells were adapted to long term O-glcnAcase (OGA) inhibition using the specific OGA inhibitor Thiamet-G (tmg) or glucosamine treatment for 3 weeks. After adaptation to the growth conditions, cells were harvest and RNA isolated for Next Generation RNA sequencing. Briefly, cDNA library was prepared using Illumina TruSeq Stranded mRNA sample preparation kit (Illumina) as manufacturer's instruction. Total RNA was isolated using the same method as previously described and 800 ng of the total RNA per reaction was used to initiate the protocol. The quality of RNA sequencing results was first assessed using FastQC (0.11.2). RSEM (1.2.22) was utilized to align the reads to the human reference genome HG38 and to calculate gene expression values. EdgeR (3.14.0) was then used to normalize the expression values using the TMM-method (weighted trimmed mean of M-values), and for differential expression analyses. First, the negative binomial conditional common likelihood was maximized to estimate a common dispersion value across all genes (estimateCommonDisp). Next, tagwise dispersion values were estimated by an empirical Bayes method based on weighted conditional maximum likelihood (estimateTagwiseDisp). Finally, the differentially gene expression was calculated by computing genewise exact tests for differences in the means between two groups of negative-binomially distributed counts. Hierarchical clustering analysis was determined using Euclidean distance. The following R-packages were utilized for calculations and visualizations: plots and edgeR.
Sustained <i>O-</i>GlcNAcylation reprograms mitochondrial function to regulate energy metabolism.
Specimen part, Cell line, Subject
View SamplesSignal transduction processes mediated by phosphatidyl inositol phosphates affect a broad range of cellular processes such as cell cycle progression, migration and cell survival. The protein kinase AKT is one of the major effectors in this signaling network. Chronic AKT activation contributes to oncogenic transformation and tumor development. Therefore, new small drugs were designed to block AKT activity for cancer treatment.
Characterization of AKT independent effects of the synthetic AKT inhibitors SH-5 and SH-6 using an integrated approach combining transcriptomic profiling and signaling pathway perturbations.
Specimen part, Cell line
View SamplesThe objective of the present study was to identify genes that are involved in increasing the ovulation number in mouse line FL1 that had been selected for high fertility performance.
Expression profiling of a high-fertility mouse line by microarray analysis and qPCR.
No sample metadata fields
View SamplesmRNA expression levels in synovial fibroblasts in 6 rheumatoid arthritis patients versus 6 osteoarthritis patients.
Constitutive upregulation of the transforming growth factor-beta pathway in rheumatoid arthritis synovial fibroblasts.
No sample metadata fields
View SamplesAcute myeloid leukemia (AML) is a heterogeneous disease and AML with normal karyotype (AML-NK) is categorized as an intermediate-risk group. Over the past years molecular analyses successfully identified biomarkers that will further allow to dissecting clinically meaningful subgroups in this disease. Thus far, somatic mutations were identified which elucidate the disturbance of cellular growth, proliferation, and differentiation processes in hematopoietic progenitor cells. In AML-NK, acquired gene mutations with prognostic relevance were identified for FLT3, CEBPA, and NPM1. FLT3-ITD mutations were associated with short relapse-free and overall survival, while mutations in CEBPA or NPM1 (without concomitant FLT3-ITD) had a more favorable outcome.
Quantitative comparison of microarray experiments with published leukemia related gene expression signatures.
Sex, Age, Disease, Disease stage
View SamplesThe purpose of this study was to characterize the transcriptional effects induced by subcutaneous IFN-beta-1b treatment (Betaferon, 250 g every other day) in patients with relapsing-remitting form of multiple sclerosis (MS).
Long-term genome-wide blood RNA expression profiles yield novel molecular response candidates for IFN-beta-1b treatment in relapsing remitting MS.
Sex
View SamplesThe purpose of this study was to characterize the transcriptional effects induced by intramuscular IFN-beta-1a treatment (Avonex, 30 g once weekly) in patients with relapsing-remitting form of multiple sclerosis (MS). By using Affymetrix DNA microarrays, we obtained genome-wide expression profiles of peripheral blood mononuclear cells from 24 MS patients within the first four weeks of IFN-beta administration.
Network analysis of transcriptional regulation in response to intramuscular interferon-β-1a multiple sclerosis treatment.
Sex
View SamplesTwo biological replicate experiments were performed to estimate the bias of the gene expression pattern of infected and non-infected HEp-2 cells. Microarrays hybridized with RNA from 2 h of non-infected HEp-2 cells were used as reference chips for the comparison with microarrays hybridized with RNA from 2 h and 4 h of eukaryotic cells exposed to wt-bacteria and .fasX-mutant. As a reference for chips hybridized with RNA prepared from 6 h p. i. and 8 h p. i. of both GAS-infected HEp-2 cells we used chips that were hybridized with RNA isolated from non-infected cells 8 h p. i. We also compared the microarray data from 2 h of non-infected HEp-2 cells with those from 8 h of non-infected HEp-2 cells to determine the influence of the extended culture on the non-infected cells. Only such genes which were differentially regulated after infection with wt-bacteria and .fasX-mutant infected cells and not differentially present in unequal amounts between the 2 h and 8 h of controls were included in the subsequent statistical analysis.
Global epithelial cell transcriptional responses reveal Streptococcus pyogenes Fas regulator activity association with bacterial aggressiveness.
Disease, Disease stage, Cell line, Time
View SamplesThe organization of mammalian DNA replication is poorly understood. We have produced genome-wide high-resolution dynamic maps of the timing of replication in human erythroid, mesenchymal and embryonic stem cells using TimEX, a method that relies on gaussian convolution of massive, highly redundant determinations of DNA copy number variations during S phase obtained using either high-density oligonucleotide tiling arrays or massively-parallel sequencing to produce replication timing profiles. We show that in untransformed human cells, timing of replication is highly regulated and highly synchronous, and that many genomic segments are replicated in temporal transition regions devoid of initiation where replication forks progress unidirectionally from origins that can be hundreds of kilobases away. Absence of initiation in one transition region is shown at the molecular level by SMARD analysis. Comparison of ES and erythroid cells replication patterns revealed that these cells replicate about 20% of their genome in different quarter of S phase and that ES cells replicate a larger proportion of their genome in early S phase than erythroid cells. Importantly, we detected a strong inverse relationship between timing of replication and distance to the closest expressed gene. This relationship can be used to predict tissue specific timing of replication profiles from expression data and genomic annotations. We also provide evidence that early origins of replication are preferentially located near highly expressed genes, that mid firing origins are located near moderately expressed genes and that late firing origins are located far from genes.
Predictable dynamic program of timing of DNA replication in human cells.
Specimen part
View SamplesThe comparative advantages of RNA-Seq and microarrays in transcriptome profiling were evaluated in the context of a comprehensive study design. Gene expression data from Illumina RNA-Seq and Affymetrix microarrays were obtained from livers of rats exposed to 27 agents that comprised of seven modes of action (MOAs); they were split into training and test sets and verified with real time PCR. Overall design: 105 samples were selected from the DrugMatirx tissue/RNA bank that is now owned by the National Toxicology Program (NTP). The samples were split into 2 sets, training and test, to allow for the evaluation of classifiers derived from the data. There were 63 samples in the training set and 42 in the test set. Of the 63 samples in the training set 45 were derived from rats treated with test agent and 18 were control samples (3 sets of 6). 39 of the test set samples were derived from test agent treated animals and 6 were from vehicle and route matched controls. Five MOAs were represented in the training set and 4 MOAs were in the test set. Two of the MOAs were duplicated from the test set and two were without representation in the training set. For each test agent there were three rats treated, in accordance with the common practice in the field of toxicology. For each MOA there were three representative test agents to ensure adequate power for detecting the MOA signatures. 6 samples from the training set had duplicate libraries sequenced and duplicate sequencing runs for the first library. DrugMatrix, National Toxicology program (NTP) Sequencing was carried out in Dr. Charles Wang's Functional Genomics Core at City of Hope Comprehensive Cancer Center, Duarte, CA
Transcriptomic profiling of rat liver samples in a comprehensive study design by RNA-Seq.
No sample metadata fields
View Samples