We have developed a total RNA amplification and labeling strategy for use with Affymetrix GeneChips. Our protocol, which we denote BIIB, employs two rounds of linear T7 amplification followed by Klenow labeling to generate a biotinylated cDNA. In benchmarking studies using a titration of mouse universal total RNA, BIIB outperformed commercially available kits in terms of sensitivity, accuracy, and amplified target length, while providing equivalent results for technical reproducibility. BIIB maintained 50 and 44% present calls from 100 and 50 pg of total RNA, respectively. Inter- and intrasample precision studies indicated that BIIB produces an unbiased and complete expression profile within a range of 5 ng to 50 pg of starting total RNA. From a panel of spiked exogenous transcripts, we established the BIIB linear detection limit to be 20 absolute copies. Additionally, we demonstrate that BIIB is sensitive enough to detect the stochastic events inherent in a highly diluted sample. Using RNA isolated from whole tissues, we further validated BIIB accuracy and precision by comparison of 224 expression ratios generated by quantitative real-time PCR. The utility of our method is ultimately illustrated by the detection of biologically expected trends in a T cell/B cell titration of 100 primary cells flow sorted from a healthy mouse spleen.
Accurate and precise transcriptional profiles from 50 pg of total RNA or 100 flow-sorted primary lymphocytes.
No sample metadata fields
View SamplesTriple-negative (TN) breast cancers need to be refined in order to identify therapeutic subgroups of patients.
Gene-expression molecular subtyping of triple-negative breast cancer tumours: importance of immune response.
Disease
View SamplesTranscriptional dysregulation in Huntingtons disease (HD) is an early event that affects the expression of genes involved in survival and neuronal functions throughout the progression of the pathology. In the last years, extensive research has focused on epigenetic and chromatin-modifying factors as a causative explanation for such dysregulation, offering attractive targets for pharmacological therapies. In this work we examined the gene expression profiles in cortex, striatum, hippocampus and cerebellum of juvenile R6/1 and N171-82Q mice, two models of fast progressive HD, to retrieve the early transcriptional signatures associated with this pathology.These profiles showed significant coincidences with the transcriptional changes in the conditional knockout for the lysine acetyltransferase CBP in postmitotic forebrain neurons.
Early alteration of epigenetic-related transcription in Huntington's disease mouse models.
Sex, Age, Specimen part
View SamplesMacrophages are a heterogeneous cell type implicated in injury, repair, and fibrosis after AKI, but the macrophage population associated with each phase is unclear.results of this study in a renal ischemia-reperfusion injury model allow phenotype and function to be assigned to CD11b+/Ly6C+ monocyte/macrophage populations in the pathophysiology of disease after AKI.
Differential Ly6C Expression after Renal Ischemia-Reperfusion Identifies Unique Macrophage Populations.
Sex, Specimen part
View SamplesThe Endoplasmic Reticulum–Mitochondria Encounter Structure (ERMES) is a protein complex that tethers the two organelles and creates the physical basis for communication between them. ERMES functions in lipid and calcium exchange between the ER and mitochondria, mitochondrial protein import and maintenance of mitochondrial morphology and genome. Here we report that ERMES is also required for iron homeostasis. Loss of ERMES components activates an Aft1-dependent iron deficiency response even in iron-replete conditions, leading to accumulation of excess iron inside the cell. This function is independent of ERMES known roles in calcium regulation, phospholipid biosynthesis or mitochondrial biology. A mutation in the vacuolar protein sorting 13 (VPS13) gene that rescues the glycolytic phenotype of ERMES mutants suppresses the iron deficiency response and iron accumulation. Our study reveals that proper communication between the ER and mitochondria is required for appropriate maintenance of cellular iron levels. Overall design: various mutants
Endoplasmic reticulum-mitochondria junction is required for iron homeostasis.
Subject
View SamplesThe N-terminal tail of histone H2A shows evolutionary changes that parallel genome size and aid chromatin compaction. As genome size increases, so does the number of arginines. In contrast, serines corellate with small genomes. Examples for such changes are arginine in position 11 and serine in position 15.
Evolution of histone 2A for chromatin compaction in eukaryotes.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Genome-wide methylation analysis in vestibular schwannomas shows putative mechanisms of gene expression modulation and global hypomethylation at the HOX gene cluster.
Specimen part
View SamplesBackground: Schwannomas and grade I meningiomas are non-metastatic neoplasms that shares the common mutation of gene NF2. They usually appear in Neurofibromatosis type 2 patients. Currently, there is no drug treatment available for both tumors, so the use of wide expression technologies is crucial to find those therapeutic targets.
Global expression profile in low grade meningiomas and schwannomas shows upregulation of PDGFD, CDH1 and SLIT2 compared to their healthy tissue.
Specimen part
View SamplesVestibular schwannomas are intracranial tumors that affects unilateral and sporadically or bilateral when is associated to Neurofibromatosis type 2 syndrome. The hallmark of the disease is the biallelic inactivation by NF2 gene mutation or LOH of chromosome 22q, where this gene harbors. In this work, we used Infinium HumanMethylation 450K BeadChip microarrays in a series of 36 vestibular schwannomas, 4 non-vestibular schwannomas and 5 healthy nerves. Our results shows a trend to hypomethylation in schwannomas. Furthermore, HOX genes, located at 4 clusters in the genome, displayed hypomethylation in numerous CpG sites in vestibular but not in non-vestibular schwannomas. Additionally, several microRNA and protein-coding genes were found hypomethylated at promoter regions and confirmed by expression analysis; including miRNA-199a1, miRNA-21, MET and PMEPA1. We also detected methylation patterns that might be involved in alternative transcripts of several genes such as NRXN1 or MBP; that would increase the complexity of methylation-expression. Overall, our results shows specific epigenetic signatures in several coding genes and microRNA that could be used in the finding of potential therapeutic targets.
Genome-wide methylation analysis in vestibular schwannomas shows putative mechanisms of gene expression modulation and global hypomethylation at the HOX gene cluster.
Specimen part
View SamplesThe quintuple jaz mutant jazQ and the triple myc mutant mycT affect plant defense and growth. We used RNA-sequencing to query the transcriptomes of jazQ and mycT, as well as the combined jazQ mycT octuple mutatant, and examined how these mutations alter the expression of genes mis-regulated in jazQ. The data highlight how jasmonate signaling pathways are largely governed by MYC transcription factors, but also highlight some MYC-independent expression patterns. Overall design: Analysis of Col-0 (wildtype), jazQ, mycT, and jazQ mycT (four genotypes), with three biological replicates per genotype - 12 total samples. This series contains the re-use of 6 samples from GSE79012 (Col-0 and jazQ).
Regulation of growth-defense balance by the JASMONATE ZIM-DOMAIN (JAZ)-MYC transcriptional module.
Age, Specimen part, Subject
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