Current methods to analyze gene expression measure steady-state levels of mRNA. In order to specifically analyze mRNA transcription, a technique has been developed that can be applied in-vivo. The technique is referred with the acronym NIAC-NTR (Non Invasive Application and Capture of Newly Transcribed RNA). This method makes use of the cellular pyrimidine salvage pathway and is based on affinity-chromatographic isolation of thiolated mRNA. When combined with data on mRNA steady-state levels, this method is able to assess the relative contributions of mRNA synthesis and degradation/stabilization. It overcomes limitations associated with currently available methods such as mechanistic intervention that disrupts cellular physiology, or the inability to apply the techniques in-vivo. The method has been applied to a model of serum response of cultured primary mouse embryonic fibroblasts.
Microarray analysis of newly synthesized RNA in cells and animals.
No sample metadata fields
View SamplesCurrent methods to analyze gene expression measure steady-state levels of mRNA. In order to specifically analyze mRNA transcription, a technique has been developed that can be applied in-vivo in intact cells and animals. The technique is referred with the acronym NIAC-NTR (Non Invasive Application and Capture of Newly Transcribed RNA). This method makes use of the cellular pyrimidine salvage pathway and is based on affinity-chromatographic isolation of thiolated mRNA. When combined with data on mRNA steady-state levels, this method is able to assess the relative contributions of mRNA synthesis and degradation/stabilization. It overcomes limitations associated with currently available methods such as mechanistic intervention that disrupts cellular physiology, or the inability to apply the techniques in-vivo. The method was applied to study renal ischemia reperfusion injury, demonstrating its applicability for whole organs in-vivo.
Microarray analysis of newly synthesized RNA in cells and animals.
Age
View SamplesThis study provides the first comprehensive analysis of gene expression and transcriptome dynamics of bovine metaphase II oocytes and in vivo developing bovine embryos.
Genome-wide expression profiling reveals distinct clusters of transcriptional regulation during bovine preimplantation development in vivo.
No sample metadata fields
View SamplesHigh-throughput sequencing of mRNA from mouse lung infected with 1918 pandemic influenza virus revealed that reactive oxygen species scavenger EUK-207 treatment resulted in decreased expression of inflammatory response genes and increased lung metabolic and repair responses.
Treatment with the reactive oxygen species scavenger EUK-207 reduces lung damage and increases survival during 1918 influenza virus infection in mice.
No sample metadata fields
View SamplesGene expression analysis has been established as a tool for the characterization of genotoxic mechanisms of chemical mutagens. This approach has been shown to differentiate between DNA reactive genotoxins and non-DNA reactive or indirectly-acting genotoxins. In this context, it has been suggested that expression analysis is capable of distinguishing compounds that cause DNA damage from those that interfere with mitotic spindle function. Formaldehyde (FA) is known to be a DNA-reactive substance which mainly induces chromosomal damage in cultured mammalian cells. However, there has been concern that FA might also act as an aneugen (i.e., induce aneuploidy) but recent cytogenetic studies did not support this assumption. To further characterize FA's genotoxic mode of action, we now used gene expression profiling as a molecular tool to differentiate between clastogenic and aneugenic activity. TK6 cells were exposed to FA for 4 and 24 h and changes in gene expression were analyzed using a whole-genome human microarray. Results were compared to the expression profiles of two DNA-damaging clastogens (methyl methanesulfonate [MMS] and ethyl methanesulfonate [EMS]) and two aneugens (colcemid [COL] and vincristine [VCR]). The gene expression profiles indicated that clastogens and aneugens induce discriminable gene expression patterns. The expression profile of FA showed more similarities to clastogens than to aneugens. Hierarchical clustering analysis as well as several class prediction algorithms revealed a much closer relationship of FA with clastogens than with aneugens. A pathway analysis of differentially regulated genes also demonstrated an overall better agreement of FA with clastogens than with aneugens. Altogether, the results of this study revealed great similarities in gene expression in response to FA and clastogens but did not support an aneugenic activity of FA.
Characterization of formaldehyde's genotoxic mode of action by gene expression analysis in TK6 cells.
Cell line, Treatment
View SamplesSteer liver transcriptome
Differential expression of genes related to gain and intake in the liver of beef cattle.
Sex, Specimen part
View SamplesMutations involving the NFKB pathway are present in at least 17% of multiple myeloma (MM) tumors and 40% of MM cell lines (MMCL). These mutations, which are thought to be progression events, enable MM tumors to become less dependent on extrinsic bone marrow signals that activate NFKB. Studies on a panel of 50 MMCL provide some clarification of the mechanisms through which these mutations act and the significance of classical vs alternative activation of NFKB. First, only one mutation (NFKB2) selectively activates the alternative pathway, whereas several mutations (CYLD, NFKB1, TACI) selectively activate the classical pathway. However, most mutations affecting NIK level (NIK, TRAF2, TRAF3, cIAP1&2, CD40) activate the alternative but often both pathways. Second, we confirm the critical role of TRAF2 in regulating NIK degradation, whereas TRAF3 enhances but is not essential for cIAP1/2-mediated proteosomal degradation of NIK in MM.
Classical and/or alternative NF-kappaB pathway activation in multiple myeloma.
Cell line
View SamplesSteer spleen transcriptome
Profile of the Spleen Transcriptome in Beef Steers with Variation in Gain and Feed Intake.
Specimen part
View SamplesEpithelial cell adhesion molecule EpCAM is a transmembrane glycoprotein that is dynamically expressed in human and murine renal epithelia during development. The levels of EpCAM in the renal epithelium are upregulated both during regeneration after ischemia/reperfusion injury and in renal-derived carcinomas. The role of EpCAM in early kidney development, however, has remained unclear. To identify potential programs and signaling pathways that are controlled by EpCAM during pronephros development, we developed a method to study the transcriptomes of specific pronephric segments. Combining laser capture microdissection (LCM) with RNA sequencing (RNA-seq), we generated genome-wide transcriptional profiles of the distal late tubules of wild type and EpCAM-deficient embryos. Overall design: RNA-seq of LCM-dissected pronephric cells from EpCAM-deficient and control zebrafish embryos
EpCAM controls morphogenetic programs during zebrafish pronephros development.
No sample metadata fields
View SamplesBiliary atresia (BA) is a rare cholestatic disease of unknown etiology that affects infants and shows an incidence of 1 out of 18,000 live births in Europe (1). The first therapeutic option is a timely performed portoenterostomy. However, the majority of patients suffer from a progressive inflammatory process, which leads to complete destruction of the extra- and intrahepatic biliary system followed by end-stage liver cirrhosis. Hence, BA is the leading indication for pediatric liver transplantation worldwide (2, 3). To understand the pathogenesis of the disease and improve theoutcome of BA patients, research has focused on the inflammatory process in liver and bile ducts, in which several factors are remarkably elevated, such as activated CD4 and CD8 T-cells, TNF alpha,IFN alpha and other proinflammatory TH1 cytokines (3-8). By the time of diagnosis, however, the disease has already reached an advanced state, characterized by the complete obstruction of the extrahepatic bile ducts with impaired bile flow and fibrosis or cirrhosis of the liver. Therefore, studies in humans focusing on the trigger mechanism of BA are limited due to the paucity of liver and availability of bile duct tissue for research. One infectious animal model has been developed, in which newborn Balb/c mice exclusively show the experimental BA phenotype after infection with rhesus rotavirus (RRV) (9, 10). This model allows the analysis of the inflammatory reactions in liver and bile ducts at early steps in the development of bile duct atresia (11-20). Furthermore, inbred mouse strains have been shown to have a different susceptibility for the development of experimental BA, suggesting that Balb/c mice have an immunological gap responsible for disease progression (10, 12). The aim of this study was to identify key genes responsible for the BA phenotype by comparing the transcriptomes at an early time point after virus infection, i.e. before bile duct atresia, between two mouse strains with different susceptibilities to BA. Differences in the virus titration and the clinical course of infected mice were analyzed, and variations in the hepatic gene response assessed by comparative microarray assays were correlated to variances in the hepatic inflammatory reaction.
Susceptibility to experimental biliary atresia linked to different hepatic gene expression profiles in two mouse strains.
Specimen part
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