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Sample records for affymetrix gene expression

  1. Gene expression in the rat brain during sleep deprivation and recovery sleep: an Affymetrix GeneChip study.

    PubMed

    Terao, A; Wisor, J P; Peyron, C; Apte-Deshpande, A; Wurts, S W; Edgar, D M; Kilduff, T S

    2006-01-01

    Previous studies have demonstrated that macromolecular synthesis in the brain is modulated in association with the occurrence of sleep and wakefulness. Similarly, the spectral composition of electroencephalographic activity that occurs during sleep is dependent on the duration of prior wakefulness. Since this homeostatic relationship between wake and sleep is highly conserved across mammalian species, genes that are truly involved in the electroencephalographic response to sleep deprivation might be expected to be conserved across mammalian species. Therefore, in the rat cerebral cortex, we have studied the effects of sleep deprivation on the expression of immediate early gene and heat shock protein mRNAs previously shown to be upregulated in the mouse brain in sleep deprivation and in recovery sleep after sleep deprivation. We find that the molecular response to sleep deprivation and recovery sleep in the brain is highly conserved between these two mammalian species, at least in terms of expression of immediate early gene and heat shock protein family members. Using Affymetrix Neurobiology U34 GeneChips , we also screened the rat cerebral cortex, basal forebrain, and hypothalamus for other genes whose expression may be modulated by sleep deprivation or recovery sleep. We find that the response of the basal forebrain to sleep deprivation is more similar to that of the cerebral cortex than to the hypothalamus. Together, these results suggest that sleep-dependent changes in gene expression in the cerebral cortex are similar across rodent species and therefore may underlie sleep history-dependent changes in sleep electroencephalographic activity.

  2. VIZARD: analysis of Affymetrix Arabidopsis GeneChip data

    NASA Technical Reports Server (NTRS)

    Moseyko, Nick; Feldman, Lewis J.

    2002-01-01

    SUMMARY: The Affymetrix GeneChip Arabidopsis genome array has proved to be a very powerful tool for the analysis of gene expression in Arabidopsis thaliana, the most commonly studied plant model organism. VIZARD is a Java program created at the University of California, Berkeley, to facilitate analysis of Arabidopsis GeneChip data. It includes several integrated tools for filtering, sorting, clustering and visualization of gene expression data as well as tools for the discovery of regulatory motifs in upstream sequences. VIZARD also includes annotation and upstream sequence databases for the majority of genes represented on the Affymetrix Arabidopsis GeneChip array. AVAILABILITY: VIZARD is available free of charge for educational, research, and not-for-profit purposes, and can be downloaded at http://www.anm.f2s.com/research/vizard/ CONTACT: moseyko@uclink4.berkeley.edu.

  3. Affymetrix GeneChip microarray preprocessing for multivariate analyses.

    PubMed

    McCall, Matthew N; Almudevar, Anthony

    2012-09-01

    Affymetrix GeneChip microarrays are the most widely used high-throughput technology to measure gene expression, and a wide variety of preprocessing methods have been developed to transform probe intensities reported by a microarray scanner into gene expression estimates. There have been numerous comparisons of these preprocessing methods, focusing on the most common analyses-detection of differential expression and gene or sample clustering. Recently, more complex multivariate analyses, such as gene co-expression, differential co-expression, gene set analysis and network modeling, are becoming more common; however, the same preprocessing methods are typically applied. In this article, we examine the effect of preprocessing methods on some of these multivariate analyses and provide guidance to the user as to which methods are most appropriate.

  4. Global Expression Patterns of Three Festuca Species Exposed to Different Doses of Glyphosate Using the Affymetrix GeneChip Wheat Genome Array.

    PubMed

    Cebeci, Ozge; Budak, Hikmet

    2009-01-01

    Glyphosate has been shown to act as an inhibitor of an aromatic amino acid biosynthetic pathway, while other pathways that may be affected by glyphosate are not known. Cross species hybridizations can provide a tool for elucidating biological pathways conserved among organisms. Comparative genome analyses have indicated a high level of colinearity among grass species and Festuca, on which we focus here, and showed rearrangements common to the Pooideae family. Based on sequence conservation among grass species, we selected the Affymetrix GeneChip Wheat Genome Array as a tool for the analysis of expression profiles of three Festuca (fescue) species with distinctly different tolerances to varying levels of glyphosate. Differences in transcript expression were recorded upon foliar glyphosate application at 1.58 mM and 6.32 mM, representing 5% and 20%, respectively, of the recommended rate. Differences highlighted categories of general metabolic processes, such as photosynthesis, protein synthesis, stress responses, and a larger number of transcripts responded to 20% glyphosate application. Differential expression of genes encoding proteins involved in the shikimic acid pathway could not be identified by cross hybridization. Microarray data were confirmed by RT-PCR and qRT-PCR analyses. This is the first report to analyze the potential of cross species hybridization in Fescue species and the data and analyses will help extend our knowledge on the cellular processes affected by glyphosate.

  5. Using probe secondary structure information to enhance Affymetrix GeneChip background estimates

    PubMed Central

    Gharaibeh, Raad Z.; Fodor, Anthony A.; Gibas, Cynthia J.

    2007-01-01

    High-density short oligonucleotide microarrays are a primary research tool for assessing global gene expression. Background noise on microarrays comprises a significant portion of the measured raw data. A number of statistical techniques have been developed to correct for this background noise. Here, we demonstrate that probe minimum folding energy and structure can be used to enhance a previously existing model for background noise correction. We estimate that probe secondary structure accounts for up to 3% of all variation on Affymetrix microarrays. PMID:17387043

  6. Improvements to previous algorithms to predict gene structure and isoform concentrations using Affymetrix Exon arrays

    PubMed Central

    2010-01-01

    Background Exon arrays provide a way to measure the expression of different isoforms of genes in an organism. Most of the procedures to deal with these arrays are focused on gene expression or on exon expression. Although the only biological analytes that can be properly assigned a concentration are transcripts, there are very few algorithms that focus on them. The reason is that previously developed summarization methods do not work well if applied to transcripts. In addition, gene structure prediction, i.e., the correspondence between probes and novel isoforms, is a field which is still unexplored. Results We have modified and adapted a previous algorithm to take advantage of the special characteristics of the Affymetrix exon arrays. The structure and concentration of transcripts -some of them possibly unknown- in microarray experiments were predicted using this algorithm. Simulations showed that the suggested modifications improved both specificity (SP) and sensitivity (ST) of the predictions. The algorithm was also applied to different real datasets showing its effectiveness and the concordance with PCR validated results. Conclusions The proposed algorithm shows a substantial improvement in the performance over the previous version. This improvement is mainly due to the exploitation of the redundancy of the Affymetrix exon arrays. An R-Package of SPACE with the updated algorithms have been developed and is freely available. PMID:21110835

  7. Analysis of discordant Affymetrix probesets casts serious doubt on idea of microarray data reutilization

    PubMed Central

    2014-01-01

    Background Affymetrix microarray technology allows one to investigate expression of thousands of genes simultaneously upon a variety of conditions. In a popular U133A microarray platform, the expression of 37% of genes is measured by more than one probeset. The discordant expression observed for two different probesets that match the same gene is a widespread phenomenon which is usually underestimated, ignored or disregarded. Results Here we evaluate the prevalence of discordant expression in data collected using Affymetrix HG-U133A microarray platform. In U133A, about 30% of genes annotated by two different probesets demonstrate a substantial correlation between independently measured expression values. To our surprise, sorting the probesets according to the nature of the discrepancy in their expression levels allowed the classification of the respective genes according to their fundamental functional properties, including observed enrichment by tissue-specific transcripts and alternatively spliced variants. On another hand, an absence of discrepancies in probesets that simultaneously match several different genes allowed us to pinpoint non-expressed pseudogenes and gene groups with highly correlated expression patterns. Nevertheless, in many cases, the nature of discordant expression of two probesets that match the same transcript remains unexplained. It is possible that these probesets report differently regulated sets of transcripts, or, in best case scenario, two different sets of transcripts that represent the same gene. Conclusion The majority of absolute gene expression values collected using Affymetrix microarrays may not be suitable for typical interpretative downstream analysis. PMID:25563078

  8. AffyTrees: facilitating comparative analysis of Affymetrix plant microarray chips.

    PubMed

    Frickey, Tancred; Benedito, Vagner Augusto; Udvardi, Michael; Weiller, Georg

    2008-02-01

    Microarrays measure the expression of large numbers of genes simultaneously and can be used to delve into interaction networks involving many genes at a time. However, it is often difficult to decide to what extent knowledge about the expression of genes gleaned in one model organism can be transferred to other species. This can be examined either by measuring the expression of genes of interest under comparable experimental conditions in other species, or by gathering the necessary data from comparable microarray experiments. However, it is essential to know which genes to compare between the organisms. To facilitate comparison of expression data across different species, we have implemented a Web-based software tool that provides information about sequence orthologs across a range of Affymetrix microarray chips. AffyTrees provides a quick and easy way of assigning which probe sets on different Affymetrix chips measure the expression of orthologous genes. Even in cases where gene or genome duplications have complicated the assignment, groups of comparable probe sets can be identified. The phylogenetic trees provide a resource that can be used to improve sequence annotation and detect biases in the sequence complement of Affymetrix chips. Being able to identify sequence orthologs and recognize biases in the sequence complement of chips is necessary for reliable cross-species microarray comparison. As the amount of work required to generate a single phylogeny in a nonautomated manner is considerable, AffyTrees can greatly reduce the workload for scientists interested in large-scale cross-species comparisons.

  9. Gene expression profile of pulpitis

    PubMed Central

    Galicia, Johnah C.; Henson, Brett R.; Parker, Joel S.; Khan, Asma A.

    2016-01-01

    The cost, prevalence and pain associated with endodontic disease necessitate an understanding of the fundamental molecular aspects of its pathogenesis. This study was aimed to identify the genetic contributors to pulpal pain and inflammation. Inflamed pulps were collected from patients diagnosed with irreversible pulpitis (n=20). Normal pulps from teeth extracted for various reasons served as controls (n=20). Pain level was assessed using a visual analog scale (VAS). Genome-wide microarray analysis was performed using Affymetrix GeneTitan Multichannel Instrument. The difference in gene expression levels were determined by the Significance Analysis of Microarray program using a false discovery rate (q-value) of 5%. Genes involved in immune response, cytokine-cytokine receptor interaction and signaling, integrin cell surface interactions, and others were expressed at relatively higher levels in the in the pulpitis group. Moreover, several genes known to modulate pain and inflammation showed differential expression in asymptomatic and mild pain patients (≥30mm on VAS) compared to those with moderate to severe pain. This exploratory study provides a molecular basis for the clinical diagnosis of pulpitis. With an enhanced understanding of pulpal inflammation, future studies on treatment and management of pulpitis and on pain associated with it can have a biological reference to bridge treatment strategies with pulpal biology. PMID:27052691

  10. Gene expression profile of pulpitis.

    PubMed

    Galicia, J C; Henson, B R; Parker, J S; Khan, A A

    2016-06-01

    The cost, prevalence and pain associated with endodontic disease necessitate an understanding of the fundamental molecular aspects of its pathogenesis. This study was aimed to identify the genetic contributors to pulpal pain and inflammation. Inflamed pulps were collected from patients diagnosed with irreversible pulpitis (n=20). Normal pulps from teeth extracted for various reasons served as controls (n=20). Pain level was assessed using a visual analog scale (VAS). Genome-wide microarray analysis was performed using Affymetrix GeneTitan Multichannel Instrument. The difference in gene expression levels were determined by the significance analysis of microarray program using a false discovery rate (q-value) of 5%. Genes involved in immune response, cytokine-cytokine receptor interaction and signaling, integrin cell surface interactions, and others were expressed at relatively higher levels in the pulpitis group. Moreover, several genes known to modulate pain and inflammation showed differential expression in asymptomatic and mild pain patients (⩾30 mm on VAS) compared with those with moderate to severe pain. This exploratory study provides a molecular basis for the clinical diagnosis of pulpitis. With an enhanced understanding of pulpal inflammation, future studies on treatment and management of pulpitis and on pain associated with it can have a biological reference to bridge treatment strategies with pulpal biology. PMID:27052691

  11. Arabidopsis gene expression patterns during spaceflight

    NASA Astrophysics Data System (ADS)

    Paul, A.-L.; Ferl, R. J.

    The exposure of Arabidopsis thaliana (Arabidopsis) plants to spaceflight environments resulted in the differential expression of hundreds of genes. A 5 day mission on orbiter Columbia in 1999 (STS-93) carried transgenic Arabidopsis plants engineered with a transgene composed of the alcohol dehydrogenase (Adh) gene promoter linked to the β -Glucuronidase (GUS) reporter gene. The plants were used to evaluate the effects of spaceflight on two fronts. First, expression patterns visualized with the Adh/GUS transgene were used to address specifically the possibility that spaceflight induces a hypoxic stress response, and to assess whether any spaceflight response was similar to control terrestrial hypoxia-induced gene expression patterns. (Paul et al., Plant Physiol. 2001, 126:613). Second, genome-wide patterns of native gene expression were evaluated utilizing the Affymetrix ATH1 GeneChip? array of 8,000 Arabidopsis genes. As a control for the veracity of the array analyses, a selection of genes identified with the arrays was further characterized with quantitative Real-Time RT PCR (ABI - TaqmanTM). Comparison of the patterns of expression for arrays of hybridized with RNA isolated from plants exposed to spaceflight compared to the control arrays revealed hundreds of genes that were differentially expressed in response to spaceflight, yet most genes that are hallmarks of hypoxic stress were unaffected. These results will be discussed in light of current models for plant responses to the spaceflight environment, and with regard to potential future flight opportunities.

  12. Transcriptome profiling and expression analyses of genes critical to wheat adaptation to low temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: To identify the genes involved in the development of low temperature (LT) tolerance in hexaploid wheat, we examined the global changes in expression in response to cold of the 55,052 potentially unique genes represented in the Affymetrix Wheat Genome microarray. We compared the expressi...

  13. A Microarray Analysis for Differential Gene Expression in the Soybean Genome Using Bioconductor and R

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes specific procedures for conducting quality assessment of Affymetrix GeneChip® soybean genome data and performing analyses to determine differential gene expression using the open-source R language and environment in conjunction with the open-source Bioconductor package. Procedu...

  14. Micro-Analyzer: automatic preprocessing of Affymetrix microarray data.

    PubMed

    Guzzi, Pietro Hiram; Cannataro, Mario

    2013-08-01

    A current trend in genomics is the investigation of the cell mechanism using different technologies, in order to explain the relationship among genes, molecular processes and diseases. For instance, the combined use of gene-expression arrays and genomic arrays has been demonstrated as an effective instrument in clinical practice. Consequently, in a single experiment different kind of microarrays may be used, resulting in the production of different types of binary data (images and textual raw data). The analysis of microarray data requires an initial preprocessing phase, that makes raw data suitable for use on existing analysis platforms, such as the TIGR M4 (TM4) Suite. An additional challenge to be faced by emerging data analysis platforms is the ability to treat in a combined way those different microarray formats coupled with clinical data. In fact, resulting integrated data may include both numerical and symbolic data (e.g. gene expression and SNPs regarding molecular data), as well as temporal data (e.g. the response to a drug, time to progression and survival rate), regarding clinical data. Raw data preprocessing is a crucial step in analysis but is often performed in a manual and error prone way using different software tools. Thus novel, platform independent, and possibly open source tools enabling the semi-automatic preprocessing and annotation of different microarray data are needed. The paper presents Micro-Analyzer (Microarray Analyzer), a cross-platform tool for the automatic normalization, summarization and annotation of Affymetrix gene expression and SNP binary data. It represents the evolution of the μ-CS tool, extending the preprocessing to SNP arrays that were not allowed in μ-CS. The Micro-Analyzer is provided as a Java standalone tool and enables users to read, preprocess and analyse binary microarray data (gene expression and SNPs) by invoking TM4 platform. It avoids: (i) the manual invocation of external tools (e.g. the Affymetrix Power

  15. Micro-Analyzer: automatic preprocessing of Affymetrix microarray data.

    PubMed

    Guzzi, Pietro Hiram; Cannataro, Mario

    2013-08-01

    A current trend in genomics is the investigation of the cell mechanism using different technologies, in order to explain the relationship among genes, molecular processes and diseases. For instance, the combined use of gene-expression arrays and genomic arrays has been demonstrated as an effective instrument in clinical practice. Consequently, in a single experiment different kind of microarrays may be used, resulting in the production of different types of binary data (images and textual raw data). The analysis of microarray data requires an initial preprocessing phase, that makes raw data suitable for use on existing analysis platforms, such as the TIGR M4 (TM4) Suite. An additional challenge to be faced by emerging data analysis platforms is the ability to treat in a combined way those different microarray formats coupled with clinical data. In fact, resulting integrated data may include both numerical and symbolic data (e.g. gene expression and SNPs regarding molecular data), as well as temporal data (e.g. the response to a drug, time to progression and survival rate), regarding clinical data. Raw data preprocessing is a crucial step in analysis but is often performed in a manual and error prone way using different software tools. Thus novel, platform independent, and possibly open source tools enabling the semi-automatic preprocessing and annotation of different microarray data are needed. The paper presents Micro-Analyzer (Microarray Analyzer), a cross-platform tool for the automatic normalization, summarization and annotation of Affymetrix gene expression and SNP binary data. It represents the evolution of the μ-CS tool, extending the preprocessing to SNP arrays that were not allowed in μ-CS. The Micro-Analyzer is provided as a Java standalone tool and enables users to read, preprocess and analyse binary microarray data (gene expression and SNPs) by invoking TM4 platform. It avoids: (i) the manual invocation of external tools (e.g. the Affymetrix Power

  16. Gene Expression and Genetic Variation in Human Atria

    PubMed Central

    Lin, Honghuang; Dolmatova, Elena V.; Morley, Michael P.; Lunetta, Kathryn L.; McManus, David D.; Magnani, Jared W.; Margulies, Kenneth B.; Hakonarson, Hakon; del Monte, Federica; Benjamin, Emelia J.; Cappola, Thomas P.; Ellinor, Patrick T.

    2013-01-01

    Background The human left and right atria have different susceptibilities to develop atrial fibrillation (AF). However, the molecular events related to structural and functional changes that enhance AF susceptibility are still poorly understood. Objective To characterize gene expression and genetic variation in human atria. Methods We studied the gene expression profiles and genetic variations in 53 left atrial and 52 right atrial tissue samples collected from the Myocardial Applied Genomics Network (MAGNet) repository. The tissues were collected from heart failure patients undergoing transplantation and from unused organ donor hearts with normal ventricular function. Gene expression was profiled using the Affymetrix GeneChip Human Genome U133A Array. Genetic variation was profiled using the Affymetrix Genome-Wide Human SNP Array 6.0. Results We found that 109 genes were differentially expressed between left and right atrial tissues. A total of 187 and 259 significant cis-associations between transcript levels and genetic variants were identified in left and right atrial tissues, respectively. We also found that a SNP at a known AF locus, rs3740293, was associated with the expression of MYOZ1 in both left and right atrial tissues. Conclusion We found a distinct transcriptional profile between the right and left atrium, and extensive cis-associations between atrial transcripts and common genetic variants. Our results implicate MYOZ1 as the causative gene at the chromosome 10q22 locus for AF. PMID:24177373

  17. Application of multidisciplinary analysis to gene expression.

    SciTech Connect

    Wang, Xuefel; Kang, Huining; Fields, Chris; Cowie, Jim R.; Davidson, George S.; Haaland, David Michael; Sibirtsev, Valeriy; Mosquera-Caro, Monica P.; Xu, Yuexian; Martin, Shawn Bryan; Helman, Paul; Andries, Erik; Ar, Kerem; Potter, Jeffrey; Willman, Cheryl L.; Murphy, Maurice H.

    2004-01-01

    Molecular analysis of cancer, at the genomic level, could lead to individualized patient diagnostics and treatments. The developments to follow will signal a significant paradigm shift in the clinical management of human cancer. Despite our initial hopes, however, it seems that simple analysis of microarray data cannot elucidate clinically significant gene functions and mechanisms. Extracting biological information from microarray data requires a complicated path involving multidisciplinary teams of biomedical researchers, computer scientists, mathematicians, statisticians, and computational linguists. The integration of the diverse outputs of each team is the limiting factor in the progress to discover candidate genes and pathways associated with the molecular biology of cancer. Specifically, one must deal with sets of significant genes identified by each method and extract whatever useful information may be found by comparing these different gene lists. Here we present our experience with such comparisons, and share methods developed in the analysis of an infant leukemia cohort studied on Affymetrix HG-U95A arrays. In particular, spatial gene clustering, hyper-dimensional projections, and computational linguistics were used to compare different gene lists. In spatial gene clustering, different gene lists are grouped together and visualized on a three-dimensional expression map, where genes with similar expressions are co-located. In another approach, projections from gene expression space onto a sphere clarify how groups of genes can jointly have more predictive power than groups of individually selected genes. Finally, online literature is automatically rearranged to present information about genes common to multiple groups, or to contrast the differences between the lists. The combination of these methods has improved our understanding of infant leukemia. While the complicated reality of the biology dashed our initial, optimistic hopes for simple answers from

  18. The Medicago truncatula gene expression atlas web server

    PubMed Central

    2009-01-01

    Background Legumes (Leguminosae or Fabaceae) play a major role in agriculture. Transcriptomics studies in the model legume species, Medicago truncatula, are instrumental in helping to formulate hypotheses about the role of legume genes. With the rapid growth of publically available Affymetrix GeneChip Medicago Genome Array GeneChip data from a great range of tissues, cell types, growth conditions, and stress treatments, the legume research community desires an effective bioinformatics system to aid efforts to interpret the Medicago genome through functional genomics. We developed the Medicago truncatula Gene Expression Atlas (MtGEA) web server for this purpose. Description The Medicago truncatula Gene Expression Atlas (MtGEA) web server is a centralized platform for analyzing the Medicago transcriptome. Currently, the web server hosts gene expression data from 156 Affymetrix GeneChip® Medicago genome arrays in 64 different experiments, covering a broad range of developmental and environmental conditions. The server enables flexible, multifaceted analyses of transcript data and provides a range of additional information about genes, including different types of annotation and links to the genome sequence, which help users formulate hypotheses about gene function. Transcript data can be accessed using Affymetrix probe identification number, DNA sequence, gene name, functional description in natural language, GO and KEGG annotation terms, and InterPro domain number. Transcripts can also be discovered through co-expression or differential expression analysis. Flexible tools to select a subset of experiments and to visualize and compare expression profiles of multiple genes have been implemented. Data can be downloaded, in part or full, in a tabular form compatible with common analytical and visualization software. The web server will be updated on a regular basis to incorporate new gene expression data and genome annotation, and is accessible at: http://bioinfo.noble.org/gene

  19. Nanobarcode gene expression monitoring system for potential miniaturized space applications

    NASA Astrophysics Data System (ADS)

    Ruan, Weiming; Eastman, P. Scott; Cooke, Patrick A.; Park, Jennifer S.; Chu, Julia S. F.; Gray, Joe W.; Li, Song; Chen, Fanqing Frank

    Manned mission to space has been threatened by various cosmos risks including radiation, mirogravity, vacuum, confinement, etc., which may cause genetic variations of astronauts and eventually lead to damages of their health. Thus, the development of small biomedical devices, which can monitor astronaut gene expression changes, is useful for future long-term space missions. Using magnetic microbeads packed with nanocrystal quantum dots at controlled ratios, we were able to generate highly multiplexed nanobarcodes, which can encode a flexible panel of genes. Also, by using a reporter quantum dot, this nanobarcode platform can monitor and quantify gene expression level with improved speed and sensitivity. As a comparison, we studied TGF-β1 induced transcription changes in human bone marrow mesenchymal stem cells with both the nanobarcode microbead system and the Affymetrix GeneChip ® HTA system, which is currently considered as the industrial standard. Though using only 1/20 of the sample RNA, the nanobarcode system showed sensitivity equivalent to Affymetrix GeneChip ® system. The coefficient of variation, dynamic range, and accuracy of the nanobarcodes measurement is equivalent to that of the GeneChip ® HTA system. Therefore, this newly invented nanobarcode microbead platform is thought to be sensitive, flexible, cost-effective and accurate in a level equivalent to the conventional methods. As an extension of the use of this new platform, spacecrafts may carry this miniaturized system as a diagnostic tool for the astronauts.

  20. Comparison of L1000 and Affymetrix Microarray for In Vitro Concentration-Response Gene Expression Profiling (SOT)

    EPA Science Inventory

    Advances in high-throughput screening technologies and in vitro systems have opened doors for cost-efficient evaluation of chemical effects on a diversity of biological endpoints. However, toxicogenomics platforms remain too costly to evaluate large libraries of chemicals in conc...

  1. Annotation of gene function in citrus using gene expression information and co-expression networks

    PubMed Central

    2014-01-01

    Background The genus Citrus encompasses major cultivated plants such as sweet orange, mandarin, lemon and grapefruit, among the world’s most economically important fruit crops. With increasing volumes of transcriptomics data available for these species, Gene Co-expression Network (GCN) analysis is a viable option for predicting gene function at a genome-wide scale. GCN analysis is based on a “guilt-by-association” principle whereby genes encoding proteins involved in similar and/or related biological processes may exhibit similar expression patterns across diverse sets of experimental conditions. While bioinformatics resources such as GCN analysis are widely available for efficient gene function prediction in model plant species including Arabidopsis, soybean and rice, in citrus these tools are not yet developed. Results We have constructed a comprehensive GCN for citrus inferred from 297 publicly available Affymetrix Genechip Citrus Genome microarray datasets, providing gene co-expression relationships at a genome-wide scale (33,000 transcripts). The comprehensive citrus GCN consists of a global GCN (condition-independent) and four condition-dependent GCNs that survey the sweet orange species only, all citrus fruit tissues, all citrus leaf tissues, or stress-exposed plants. All of these GCNs are clustered using genome-wide, gene-centric (guide) and graph clustering algorithms for flexibility of gene function prediction. For each putative cluster, gene ontology (GO) enrichment and gene expression specificity analyses were performed to enhance gene function, expression and regulation pattern prediction. The guide-gene approach was used to infer novel roles of genes involved in disease susceptibility and vitamin C metabolism, and graph-clustering approaches were used to investigate isoprenoid/phenylpropanoid metabolism in citrus peel, and citric acid catabolism via the GABA shunt in citrus fruit. Conclusions Integration of citrus gene co-expression networks

  2. A microarray analysis for differential gene expression in the soybean genome using Bioconductor and R.

    PubMed

    Gregory Alvord, W; Roayaei, Jean A; Quiñones, Octavio A; Schneider, Katherine T

    2007-11-01

    This article describes specific procedures for conducting quality assessment of Affymetrix GeneChip(R) soybean genome data and for performing analyses to determine differential gene expression using the open-source R programming environment in conjunction with the open-source Bioconductor software. We describe procedures for extracting those Affymetrix probe set IDs related specifically to the soybean genome on the Affymetrix soybean chip and demonstrate the use of exploratory plots including images of raw probe-level data, boxplots, density plots and M versus A plots. RNA degradation and recommended procedures from Affymetrix for quality control are discussed. An appropriate probe-level model provides an excellent quality assessment tool. To demonstrate this, we discuss and display chip pseudo-images of weights, residuals and signed residuals and additional probe-level modeling plots that may be used to identify aberrant chips. The Robust Multichip Averaging (RMA) procedure was used for background correction, normalization and summarization of the AffyBatch probe-level data to obtain expression level data and to discover differentially expressed genes. Examples of boxplots and MA plots are presented for the expression level data. Volcano plots and heatmaps are used to demonstrate the use of (log) fold changes in conjunction with ordinary and moderated t-statistics for determining interesting genes. We show, with real data, how implementation of functions in R and Bioconductor successfully identified differentially expressed genes that may play a role in soybean resistance to a fungal pathogen, Phakopsora pachyrhizi. Complete source code for performing all quality assessment and statistical procedures may be downloaded from our web source: http://css.ncifcrf.gov/services/download/MicroarraySoybean.zip.

  3. Identification of Potential Anticancer Activities of Novel Ganoderma lucidum Extracts Using Gene Expression and Pathway Network Analysis.

    PubMed

    Kao, Chi H J; Bishop, Karen S; Xu, Yuanye; Han, Dug Yeo; Murray, Pamela M; Marlow, Gareth J; Ferguson, Lynnette R

    2016-01-01

    Ganoderma lucidum (lingzhi) has been used for the general promotion of health in Asia for many centuries. The common method of consumption is to boil lingzhi in water and then drink the liquid. In this study, we examined the potential anticancer activities of G. lucidum submerged in two commonly consumed forms of alcohol in East Asia: malt whiskey and rice wine. The anticancer effect of G. lucidum, using whiskey and rice wine-based extraction methods, has not been previously reported. The growth inhibition of G. lucidum whiskey and rice wine extracts on the prostate cancer cell lines, PC3 and DU145, was determined. Using Affymetrix gene expression assays, several biologically active pathways associated with the anticancer activities of G. lucidum extracts were identified. Using gene expression analysis (real-time polymerase chain reaction [RT-PCR]) and protein analysis (Western blotting), we confirmed the expression of key genes and their associated proteins that were initially identified with Affymetrix gene expression analysis.

  4. Epigenetics and gene expression.

    PubMed

    Gibney, E R; Nolan, C M

    2010-07-01

    Transcription, translation and subsequent protein modification represent the transfer of genetic information from the archival copy of DNA to the short-lived messenger RNA, usually with subsequent production of protein. Although all cells in an organism contain essentially the same DNA, cell types and functions differ because of qualitative and quantitative differences in their gene expression. Thus, control of gene expression is at the heart of differentiation and development. Epigenetic processes, including DNA methylation, histone modification and various RNA-mediated processes, are thought to influence gene expression chiefly at the level of transcription; however, other steps in the process (for example, translation) may also be regulated epigenetically. The following paper will outline the role epigenetics is believed to have in influencing gene expression.

  5. A gene expression screen.

    PubMed Central

    Wang, Z; Brown, D D

    1991-01-01

    A gene expression screen identifies mRNAs that differ in abundance between two mRNA mixtures by a subtractive hybridization method. The two mRNA populations are converted to double-stranded cDNAs, fragmented, and ligated to linkers for polymerase chain reaction (PCR) amplification. The multiple cDNA fragments isolated from any given gene can be treated as alleles in a genetic screen. Probability analysis of the frequency with which multiple alleles are found provides an estimation of the total number of up- and down-regulated genes. We have applied this method to genes that are differentially expressed in amphibian tadpole tail tissue in the first 24 hr after thyroid hormone treatment, which ultimately induces tail resorption. We estimate that there are about 30 up-regulated genes; 16 have been isolated. Images PMID:1722336

  6. ACNE: a summarization method to estimate allele-specific copy numbers for Affymetrix SNP arrays

    PubMed Central

    Ortiz-Estevez, Maria; Bengtsson, Henrik; Rubio, Angel

    2010-01-01

    Motivation: Current algorithms for estimating DNA copy numbers (CNs) borrow concepts from gene expression analysis methods. However, single nucleotide polymorphism (SNP) arrays have special characteristics that, if taken into account, can improve the overall performance. For example, cross hybridization between alleles occurs in SNP probe pairs. In addition, most of the current CN methods are focused on total CNs, while it has been shown that allele-specific CNs are of paramount importance for some studies. Therefore, we have developed a summarization method that estimates high-quality allele-specific CNs. Results: The proposed method estimates the allele-specific DNA CNs for all Affymetrix SNP arrays dealing directly with the cross hybridization between probes within SNP probesets. This algorithm outperforms (or at least it performs as well as) other state-of-the-art algorithms for computing DNA CNs. It better discerns an aberration from a normal state and it also gives more precise allele-specific CNs. Availability: The method is available in the open-source R package ACNE, which also includes an add on to the aroma.affymetrix framework (http://www.aroma-project.org/). Contact: arubio@ceit.es Supplementaruy information: Supplementary data are available at Bioinformatics online. PMID:20529889

  7. Gene expression technology

    SciTech Connect

    Goeddel, D.V. )

    1990-01-01

    The articles in this volume were assemble to enable the reader to design effective strategies for the expression of cloned genes and cDNAs. More than a compilation of papers describing the multitude of techniques now available for expressing cloned genes, this volume provides a manual that should prove useful for solving the majority of expression problems one likely to encounter. The four major expression systems commonly available to most investigators are stressed: Escherichia coli, Bacillus subtilis, yeast, and mammalian cells. Each of these system has its advantages and disadvantages, details of which are found in Chapter 1 and the strategic overviews for the four major sections of the volume. The papers in each of these sections provide many suggestions on how to proceed if initial expression levels are not sufficient.

  8. Gene structure and expression

    SciTech Connect

    Hawkins, J. )

    1990-01-01

    This book describes the structure of genes in molecular terms and summarizes present knowledge about how their activity is regulated. It covers a range of topics, including a review of the structure and replication of DNA, transcription and translation, prokaryotic and eukaryotic gene organization and expression, retroviruses and oncogenes. The book also includes a chapter on the methodology of DNA manipulation including sections on site-directed mutagenesis, the polymerase chain reaction, reporter genes and restriction fragment length polymorphisms. The hemoglobin gene system and the genetics of the proteins of the immune system are presented in the latter half of the book to show the structure and expression of the most well-studied systems in higher eukaryotes. The final chapter reviews the differences between prokaryotic and the eukaryotic genomes.

  9. Peripheral blood gene expression profiles in COPD subjects.

    PubMed

    Bhattacharya, Soumyaroop; Tyagi, Shivraj; Srisuma, Sorachai; Demeo, Dawn L; Shapiro, Steven D; Bueno, Raphael; Silverman, Edwin K; Reilly, John J; Mariani, Thomas J

    2011-01-01

    To identify non-invasive gene expression markers for chronic obstructive pulmonary disease (COPD), we performed genome-wide expression profiling of peripheral blood samples from 12 subjects with significant airflow obstruction and an equal number of non-obstructed controls. RNA was isolated from Peripheral Blood Mononuclear Cells (PBMCs) and gene expression was assessed using Affymetrix U133 Plus 2.0 arrays.Tests for gene expression changes that discriminate between COPD cases (FEV1< 70% predicted, FEV1/FVC < 0.7) and controls (FEV1> 80% predicted, FEV1/FVC > 0.7) were performed using Significance Analysis of Microarrays (SAM) and Bayesian Analysis of Differential Gene Expression (BADGE). Using either test at high stringency (SAM median FDR = 0 or BADGE p < 0.01) we identified differential expression for 45 known genes. Correlation of gene expression with lung function measurements (FEV1 & FEV1/FVC), using both Pearson and Spearman correlation coefficients (p < 0.05), identified a set of 86 genes. A total of 16 markers showed evidence of significant correlation (p < 0.05) with quantitative traits and differential expression between cases and controls. We further compared our peripheral gene expression markers with those we previously identified from lung tissue of the same cohort. Two genes, RP9and NAPE-PLD, were identified as decreased in COPD cases compared to controls in both lung tissue and blood. These results contribute to our understanding of gene expression changes in the peripheral blood of patients with COPD and may provide insight into potential mechanisms involved in the disease. PMID:21884629

  10. MAAMD: a workflow to standardize meta-analyses and comparison of affymetrix microarray data

    PubMed Central

    2014-01-01

    Background Mandatory deposit of raw microarray data files for public access, prior to study publication, provides significant opportunities to conduct new bioinformatics analyses within and across multiple datasets. Analysis of raw microarray data files (e.g. Affymetrix CEL files) can be time consuming, complex, and requires fundamental computational and bioinformatics skills. The development of analytical workflows to automate these tasks simplifies the processing of, improves the efficiency of, and serves to standardize multiple and sequential analyses. Once installed, workflows facilitate the tedious steps required to run rapid intra- and inter-dataset comparisons. Results We developed a workflow to facilitate and standardize Meta-Analysis of Affymetrix Microarray Data analysis (MAAMD) in Kepler. Two freely available stand-alone software tools, R and AltAnalyze were embedded in MAAMD. The inputs of MAAMD are user-editable csv files, which contain sample information and parameters describing the locations of input files and required tools. MAAMD was tested by analyzing 4 different GEO datasets from mice and drosophila. MAAMD automates data downloading, data organization, data quality control assesment, differential gene expression analysis, clustering analysis, pathway visualization, gene-set enrichment analysis, and cross-species orthologous-gene comparisons. MAAMD was utilized to identify gene orthologues responding to hypoxia or hyperoxia in both mice and drosophila. The entire set of analyses for 4 datasets (34 total microarrays) finished in ~ one hour. Conclusions MAAMD saves time, minimizes the required computer skills, and offers a standardized procedure for users to analyze microarray datasets and make new intra- and inter-dataset comparisons. PMID:24621103

  11. Circadian Variations in Liver Gene Expression: Relationships to Drug Actions

    PubMed Central

    Almon, Richard R.; Yang, Eric; Lai, William; Androulakis, Ioannis P.; DuBois, Debra C.; Jusko, William J.

    2008-01-01

    Chronopharmacology is an important but under-explored aspect of therapeutics. Rhythmic variations in biological processes can influence drug action, including pharmacodynamic responses, due to circadian variations in the availability or functioning of drug targets. We hypothesized that global gene expression analysis can be useful in the identification of circadian regulated genes involved in drug action. Circadian variations in gene expression in rat liver were explored using Affymetrix gene arrays. A rich time series involving animals analyzed at 18 time points within the 24 hour cycle was generated. Of the more than 15,000 probe sets on these arrays, 265 exhibited oscillations with a 24 hour frequency. Cluster analysis yielded 5 distinct circadian clusters, with approximately two-thirds of the transcripts reaching maximum expression during the animal’s dark/active period. Of the 265 probe sets, 107 of potential therapeutic importance were identified. The expression levels of clock genes were also investigated in this study. Five clock genes exhibited circadian variation in liver, and data suggest that these genes may also be regulated by corticosteroids. PMID:18562560

  12. Gene expression profiles of bronchoalveolar cells in Pulmonary TB

    PubMed Central

    Raju, Bindu; Hoshino, Yoshihiko; Belitskaya-Lévy, Ilana; Dawson, Rod; Ress, Stanley; Gold, Jeffrey A.; Condos, Rany; Pine, Richard; Brown, Stuart; Nolan, Anna; Rom, William N.; Weiden, Michael D.

    2008-01-01

    The host response to Mycobacterium tuberculosis includes macrophage activation, inflammation with increased immune effector cells, tissue necrosis and cavity formation, and fibrosis, distortion, and bronchiectasis. To evaluate the molecular basis of the immune response in the lungs of patients with active pulmonary tuberculosis (TB), we used bronchoalveolar lavage to obtain cells at the site of infection. Affymetrix Genechip micro-arrays and cDNA nylon filter microarrays interrogated gene expression in BAL cells from 11 healthy controls and 17 patients with active pulmonary TB. We found altered gene expression for 69 genes in TB versus normal controls that included cell surface markers, cytokines, chemokines, receptors, transcription factors, and complement components. In addition, TB BAL cell gene expression patternssegregated into 2 groups: one suggestive of a T helper type 1 (Th1) cellular immune response with increased STAT-4, IFN-γ receptor, and MIG expression with increased IFN-γ protein levels in BAL fluid; the other group displayed characteristics of Th2 immunity with increased STAT-6, CD81, and IL-10 receptor expression. We were able to demonstrate that a Th2 presentation could change to a Th1 pattern after anti-tuberculous treatment in one TB patient studied serially. These gene expression data support the conclusion that pulmonary TB produces a global change in the BAL cell transcriptome with manifestations of either Th1 or Th2 immunity. PMID:17921069

  13. Gene Expression During Drosophila Wing Morphogenesis and Differentiation

    PubMed Central

    Ren, Nan; Zhu, Chunming; Lee, Haeryun; Adler, Paul N.

    2005-01-01

    The simple cellular composition and array of distally pointing hairs has made the Drosophila wing a favored system for studying planar polarity and the coordination of cellular and tissue level morphogenesis. We carried out a gene expression screen to identify candidate genes that functioned in wing and wing hair morphogenesis. Pupal wing RNA was isolated from tissue prior to, during, and after hair growth and used to probe Affymetrix Drosophila gene chips. We identified 435 genes whose expression changed at least fivefold during this period and 1335 whose expression changed at least twofold. As a functional validation we chose 10 genes where genetic reagents existed but where there was little or no evidence for a wing phenotype. New phenotypes were found for 9 of these genes, providing functional validation for the collection of identified genes. Among the phenotypes seen were a delay in hair initiation, defects in hair maturation, defects in cuticle formation and pigmentation, and abnormal wing hair polarity. The collection of identified genes should be a valuable data set for future studies on hair and bristle morphogenesis, cuticle synthesis, and planar polarity. PMID:15998724

  14. The rules of gene expression in plants: Organ identity and gene body methylation are key factors for regulation of gene expression in Arabidopsis thaliana

    PubMed Central

    Aceituno, Felipe F; Moseyko, Nick; Rhee, Seung Y; Gutiérrez, Rodrigo A

    2008-01-01

    Background Microarray technology is a widely used approach for monitoring genome-wide gene expression. For Arabidopsis, there are over 1,800 microarray hybridizations representing many different experimental conditions on Affymetrix™ ATH1 gene chips alone. This huge amount of data offers a unique opportunity to infer the principles that govern the regulation of gene expression in plants. Results We used bioinformatics methods to analyze publicly available data obtained using the ATH1 chip from Affymetrix. A total of 1887 ATH1 hybridizations were normalized and filtered to eliminate low-quality hybridizations. We classified and compared control and treatment hybridizations and determined differential gene expression. The largest differences in gene expression were observed when comparing samples obtained from different organs. On average, ten-fold more genes were differentially expressed between organs as compared to any other experimental variable. We defined "gene responsiveness" as the number of comparisons in which a gene changed its expression significantly. We defined genes with the highest and lowest responsiveness levels as hypervariable and housekeeping genes, respectively. Remarkably, housekeeping genes were best distinguished from hypervariable genes by differences in methylation status in their transcribed regions. Moreover, methylation in the transcribed region was inversely correlated (R2 = 0.8) with gene responsiveness on a genome-wide scale. We provide an example of this negative relationship using genes encoding TCA cycle enzymes, by contrasting their regulatory responsiveness to nitrate and methylation status in their transcribed regions. Conclusion Our results indicate that the Arabidopsis transcriptome is largely established during development and is comparatively stable when faced with external perturbations. We suggest a novel functional role for DNA methylation in the transcribed region as a key determinant capable of restraining the

  15. Microarray analysis of relative gene expression stability for selection of internal reference genes in the rhesus macaque brain

    PubMed Central

    2010-01-01

    Background Normalization of gene expression data refers to the comparison of expression values using reference standards that are consistent across all conditions of an experiment. In PCR studies, genes designated as "housekeeping genes" have been used as internal reference genes under the assumption that their expression is stable and independent of experimental conditions. However, verification of this assumption is rarely performed. Here we assess the use of gene microarray analysis to facilitate selection of internal reference sequences with higher expression stability across experimental conditions than can be expected using traditional selection methods. We recently demonstrated that relative gene expression from qRT-PCR data normalized using GAPDH, ALG9 and RPL13A expression values mirrored relative expression using quantile normalization in Robust Multichip Analysis (RMA) on the Affymetrix® GeneChip® rhesus Macaque Genome Array. Having shown that qRT-PCR and Affymetrix® GeneChip® data from the same hormone replacement therapy (HRT) study yielded concordant results, we used quantile-normalized gene microarray data to identify the most stably expressed among probe sets for prospective internal reference genes across three brain regions from the HRT study and an additional study of normally menstruating rhesus macaques (cycle study). Gene selection was limited to 575 previously published human "housekeeping" genes. Twelve animals were used per study, and three brain regions were analyzed from each animal. Gene expression stabilities were determined using geNorm, NormFinder and BestKeeper software packages. Results Sequences co-annotated for ribosomal protein S27a (RPS27A), and ubiquitin were among the most stably expressed under all conditions and selection criteria used for both studies. Higher annotation quality on the human GeneChip® facilitated more targeted analysis than could be accomplished using the rhesus GeneChip®. In the cycle study, multiple

  16. PINTA: a web server for network-based gene prioritization from expression data.

    PubMed

    Nitsch, Daniela; Tranchevent, Léon-Charles; Gonçalves, Joana P; Vogt, Josef Korbinian; Madeira, Sara C; Moreau, Yves

    2011-07-01

    PINTA (available at http://www.esat.kuleuven.be/pinta/; this web site is free and open to all users and there is no login requirement) is a web resource for the prioritization of candidate genes based on the differential expression of their neighborhood in a genome-wide protein-protein interaction network. Our strategy is meant for biological and medical researchers aiming at identifying novel disease genes using disease specific expression data. PINTA supports both candidate gene prioritization (starting from a user defined set of candidate genes) as well as genome-wide gene prioritization and is available for five species (human, mouse, rat, worm and yeast). As input data, PINTA only requires disease specific expression data, whereas various platforms (e.g. Affymetrix) are supported. As a result, PINTA computes a gene ranking and presents the results as a table that can easily be browsed and downloaded by the user. PMID:21602267

  17. Obesity in BSB mice is correlated with expression of genes foriron homeostasis and leptin

    SciTech Connect

    Farahani, Poupak; Chiu, Sally; Bowlus, Christopher L.; Boffelli,Dario; Lee, Eric; Fisler, Janis S.; Krauss, Ronald M.; Warden, Craig H.

    2003-04-01

    Obesity is a complex disease. To date, over 100 chromosomal loci for body weight, body fat, regional white adipose tissue weight, and other obesity-related traits have been identified in humans and in animal models. For most loci, the underlying genes are not yet identified; some of these chromosomal loci will be alleles of known obesity genes, whereas many will represent alleles of unknown genes. Microarray analysis allows simultaneous multiple gene and pathway discovery. cDNA and oligonucleotide arrays are commonly used to identify differentially expressed genes by surveys of large numbers of known and unnamed genes. Two papers previously identified genes differentially expressed in adipose tissue of mouse models of obesity and diabetes by analysis of hybridization to Affymetrix oligonucleotide chips.

  18. Age and Diet Affect Gene Expression Profile in Canine Skeletal Muscle

    PubMed Central

    Middelbos, Ingmar S.; Vester, Brittany M.; Karr-Lilienthal, Lisa K.; Schook, Lawrence B.; Swanson, Kelly S.

    2009-01-01

    We evaluated gene transcription in canine skeletal muscle (biceps femoris) using microarray analysis to identify effects of age and diet on gene expression. Twelve female beagles were used (six 1-year olds and six 12-year olds) and they were fed one of two experimental diets for 12 months. One diet contained primarily plant-based protein sources (PPB), whereas the second diet contained primarily animal-based protein sources (APB). Affymetrix GeneChip Canine Genome Arrays were used to hybridize extracted RNA. Age had the greatest effect on gene transcription (262 differentially expressed genes), whereas the effect of diet was relatively small (22 differentially expressed genes). Effects of age (regardless of diet) were most notable on genes related to metabolism, cell cycle and cell development, and transcription function. All these genes were predominantly down-regulated in geriatric dogs. Age-affected genes that were differentially expressed on only one of two diets were primarily noted in the PPB diet group (144/165 genes). Again, genes related to cell cycle (22/35) and metabolism (15/19) had predominantly decreased transcription in geriatric dogs, but 6/8 genes related to muscle development had increased expression. Effects of diet on muscle gene expression were mostly noted in geriatric dogs, but no consistent patterns in transcription were observed. The insight these data provide into gene expression profiles of canine skeletal muscle as affected by age, could serve as a foundation for future research pertaining to age-related muscle diseases. PMID:19221602

  19. Identification of Cancer Related Genes Using a Comprehensive Map of Human Gene Expression

    PubMed Central

    Lukk, Margus; Xue, Vincent; Parkinson, Helen; Rung, Johan; Brazma, Alvis

    2016-01-01

    Rapid accumulation and availability of gene expression datasets in public repositories have enabled large-scale meta-analyses of combined data. The richness of cross-experiment data has provided new biological insights, including identification of new cancer genes. In this study, we compiled a human gene expression dataset from ∼40,000 publicly available Affymetrix HG-U133Plus2 arrays. After strict quality control and data normalisation the data was quantified in an expression matrix of ∼20,000 genes and ∼28,000 samples. To enable different ways of sample grouping, existing annotations where subjected to systematic ontology assisted categorisation and manual curation. Groups like normal tissues, neoplasmic tissues, cell lines, homoeotic cells and incompletely differentiated cells were created. Unsupervised analysis of the data confirmed global structure of expression consistent with earlier analysis but with more details revealed due to increased resolution. A suitable mixed-effects linear model was used to further investigate gene expression in solid tissue tumours, and to compare these with the respective healthy solid tissues. The analysis identified 1,285 genes with systematic expression change in cancer. The list is significantly enriched with known cancer genes from large, public, peer-reviewed databases, whereas the remaining ones are proposed as new cancer gene candidates. The compiled dataset is publicly available in the ArrayExpress Archive. It contains the most diverse collection of biological samples, making it the largest systematically annotated gene expression dataset of its kind in the public domain. PMID:27322383

  20. DMET-Analyzer: automatic analysis of Affymetrix DMET Data

    PubMed Central

    2012-01-01

    Background Clinical Bioinformatics is currently growing and is based on the integration of clinical and omics data aiming at the development of personalized medicine. Thus the introduction of novel technologies able to investigate the relationship among clinical states and biological machineries may help the development of this field. For instance the Affymetrix DMET platform (drug metabolism enzymes and transporters) is able to study the relationship among the variation of the genome of patients and drug metabolism, detecting SNPs (Single Nucleotide Polymorphism) on genes related to drug metabolism. This may allow for instance to find genetic variants in patients which present different drug responses, in pharmacogenomics and clinical studies. Despite this, there is currently a lack in the development of open-source algorithms and tools for the analysis of DMET data. Existing software tools for DMET data generally allow only the preprocessing of binary data (e.g. the DMET-Console provided by Affymetrix) and simple data analysis operations, but do not allow to test the association of the presence of SNPs with the response to drugs. Results We developed DMET-Analyzer a tool for the automatic association analysis among the variation of the patient genomes and the clinical conditions of patients, i.e. the different response to drugs. The proposed system allows: (i) to automatize the workflow of analysis of DMET-SNP data avoiding the use of multiple tools; (ii) the automatic annotation of DMET-SNP data and the search in existing databases of SNPs (e.g. dbSNP), (iii) the association of SNP with pathway through the search in PharmaGKB, a major knowledge base for pharmacogenomic studies. DMET-Analyzer has a simple graphical user interface that allows users (doctors/biologists) to upload and analyse DMET files produced by Affymetrix DMET-Console in an interactive way. The effectiveness and easy use of DMET Analyzer is demonstrated through different case studies regarding

  1. High magnetic field induced changes of gene expression in arabidopsis

    PubMed Central

    Paul, Anna-Lisa; Ferl, Robert J; Meisel, Mark W

    2006-01-01

    Background High magnetic fields are becoming increasingly prevalent components of non-invasive, biomedical imaging tools (such as MRI), thus, an understanding of the molecular impacts associated with these field strengths in biological systems is of central importance. The biological impact of magnetic field strengths up to 30 Tesla were investigated in this study through the use of transgenic Arabidopsis plants engineered with a stress response gene consisting of the alcohol dehydrogenase (Adh) gene promoter driving the β-glucuronidase (GUS) gene reporter. Methods Magnetic field induced Adh/GUS activity was evaluated with histochemical staining to assess tissue specific expression and distribution, and with quantitative, spectrofluometric assays to measure degree of activation. The evaluation of global changes in the Arabidopsis genome in response to exposure to high magnetic fields was facilitated with Affymetrix Gene Chip microarrays. Quantitative analyses of gene expression were performed with quantitative real-time polymerase-chain-reaction (qRT-PCR). Results Field strengths in excess of about 15 Tesla induce expression of the Adh/GUS transgene in the roots and leaves. From the microarray analyses that surveyed 8000 genes, 114 genes were differentially expressed to a degree greater than 2.5 fold over the control. These results were quantitatively corroborated by qRT-PCR examination of 4 of the 114 genes. Conclusion The data suggest that magnetic fields in excess of 15 Tesla have far-reaching effect on the genome. The wide-spread induction of stress-related genes and transcription factors, and a depression of genes associated with cell wall metabolism, are prominent examples. The roles of magnetic field orientation of macromolecules and magnetophoretic effects are discussed as possible factors that contribute to the mounting of this response. PMID:17187667

  2. Identifying the impact of G-quadruplexes on Affymetrix 3' arrays using cloud computing.

    PubMed

    Memon, Farhat N; Owen, Anne M; Sanchez-Graillet, Olivia; Upton, Graham J G; Harrison, Andrew P

    2010-01-15

    A tetramer quadruplex structure is formed by four parallel strands of DNA/ RNA containing runs of guanine. These quadruplexes are able to form because guanine can Hoogsteen hydrogen bond to other guanines, and a tetrad of guanines can form a stable arrangement. Recently we have discovered that probes on Affymetrix GeneChips that contain runs of guanine do not measure gene expression reliably. We associate this finding with the likelihood that quadruplexes are forming on the surface of GeneChips. In order to cope with the rapidly expanding size of GeneChip array datasets in the public domain, we are exploring the use of cloud computing to replicate our experiments on 3' arrays to look at the effect of the location of G-spots (runs of guanines). Cloud computing is a recently introduced high-performance solution that takes advantage of the computational infrastructure of large organisations such as Amazon and Google. We expect that cloud computing will become widely adopted because it enables bioinformaticians to avoid capital expenditure on expensive computing resources and to only pay a cloud computing provider for what is used. Moreover, as well as financial efficiency, cloud computing is an ecologically-friendly technology, it enables efficient data-sharing and we expect it to be faster for development purposes. Here we propose the advantageous use of cloud computing to perform a large data-mining analysis of public domain 3' arrays.

  3. Gene Express Inc.

    PubMed

    Saccomanno, Colette F

    2006-07-01

    Gene Express, Inc. is a technology-licensing company and provider of Standardized Reverse Transcription Polymerase Chain Reaction (StaRT-PCR) services. Designed by and for clinical researchers involved in pharmaceutical, biomarker and molecular diagnostic product development, StaRT-PCR is a unique quantitative and standardized multigene expression measurement platform. StaRT-PCR meets all of the performance characteristics defined by the US FDA as required to support regulatory submissions [101,102] , and by the Clinical Laboratory Improvement Act of 1988 (CLIA) as necessary to support diagnostic testing [1] . A standardized mixture of internal standards (SMIS), manufactured in bulk, provides integrated quality control wherein each native template target gene is measured relative to a competitive template internal standard. Bulk production enables the compilation of a comprehensive standardized database from across multiple experiments, across collaborating laboratories and across the entire clinical development lifecycle of a given compound or diagnostic product. For the first time, all these data are able to be directly compared. Access to such a database can dramatically shorten the time from investigational new drug (IND) to new drug application (NDA), or save time and money by hastening a substantiated 'no-go' decision. High-throughput StaRT-PCR is conducted at the company's automated Standardized Expression Measurement (SEM) Center. Currently optimized for detection on a microcapillary electrophoretic platform, StaRT-PCR products also may be analyzed on microarray, high-performance liquid chromatography (HPLC), or matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) platforms. SEM Center services deliver standardized genomic data--data that will accelerate the application of pharmacogenomic technology to new drug and diagnostic test development and facilitate personalized medicine.

  4. HIV-associated mucosal gene expression: region-specific alterations

    PubMed Central

    Voigt, Robin M.; Keshavarzian, Ali; Losurdo, John; Swanson, Garth; Siewe, Basile; Forsyth, Christopher B.; French, Audrey L.; Demarais, Patricia; Engen, Phillip; Raeisi, Shohreh; Mutlu, Ece; Landay, Alan L.

    2016-01-01

    Objective Despite the use of HAART to control HIV, systemic immune activation and inflammation persists with the consequence of developing serious non-AIDS events. The mechanisms that contribute to persistent systemic immune activation have not been well defined. The intestine is the major source of “sterile” inflammation and plays a critical role in immune function; thus, we sought to determine whether intestinal gene expression was altered in virally controlled HIV-infected individuals. Design and methods Gene expression was compared in biopsy samples collected from HIV-uninfected and HIV-infected individuals from the ileum, right colon (ascending colon), and left colon (sigmoid). Affymetrix gene arrays were performed on tissues and pathway analyses were conducted. Gene expression was correlated with systemic markers of intestinal barrier dysfunction and inflammation and intestinal microbiota composition. Results Genes involved in cellular immune response, cytokine signaling, pathogen-influenced signaling, humoral immune response, apoptosis, intracellular and second messenger signaling, cancer, organismal growth and development, and proliferation and development were upregulated in the intestine of HIV-infected individuals with differences observed in the ileum, right, and left colon. Gene expression in the ileum primarily correlated with systemic markers of inflammation (e.g., IL7R, IL2, and TLR2 with serum TNF) whereas expression in the colon correlated with the microbiota community (e.g., IFNG, IL1B, and CD3G with Bacteroides). Conclusion These data demonstrate persistent, proinflammatory changes in the intestinal mucosa of virally suppressed HIV-infected individuals. These changes in intestinal gene expression may be the consequence of or contribute to barrier dysfunction and intestinal dysbiosis observed in HIV. PMID:25587909

  5. Microarray analysis of gene expression in mouse (strain 129) embryonic stem cells after typical synthetic musk exposure.

    PubMed

    Shi, Jiachen; Li, Ming; Jiao, Zhihao; Zhang, Jing; Feng, Yixing; Shao, Bing

    2013-01-01

    Synthetic musks are widely used in personal-care products and can readily accumulate in the adipose tissue, breast milk, and blood of humans. In this study, the Affymetrix Mouse Genome GeneChip was used to identify alterations in gene expression of embryonic stem cells from the 129 strain of the laboratory mouse after treatment with the synthetic musk tonalide (AHTN). Among the 45,037 transcripts in the microarray, 2,879 genes were differentially expressed. According to the microarray analysis, the potential influence of AHTN on the development to embryo should be of concern, and the toxicological effects of it and related musk compounds should be studied further.

  6. Dexpanthenol modulates gene expression in skin wound healing in vivo.

    PubMed

    Heise, R; Skazik, C; Marquardt, Y; Czaja, K; Sebastian, K; Kurschat, P; Gan, L; Denecke, B; Ekanayake-Bohlig, S; Wilhelm, K-P; Merk, H F; Baron, J M

    2012-01-01

    Topical application of dexpanthenol is widely used in clinical practice for the improvement of wound healing. Previous in vitro experiments identified a stimulatory effect of pantothenate on migration, proliferation and gene regulation in cultured human dermal fibroblasts. To correlate these in vitro findings with the more complex in vivo situation of wound healing, a clinical trial was performed in which the dexpanthenol-induced gene expression profile in punch biopsies of previously injured and dexpanthenol-treated skin in comparison to placebo-treated skin was analyzed at the molecular level by Affymetrix® GeneChip analysis. Upregulation of IL-6, IL-1β, CYP1B1, CXCL1, CCL18 and KAP 4-2 gene expression and downregulation of psorasin mRNA and protein expression were identified in samples treated topically with dexpanthenol. This in vivo study might provide new insight into the molecular mechanisms responsible for the effect of dexpanthenol in wound healing and shows strong correlations to previous in vitro data using cultured dermal fibroblasts. PMID:22759998

  7. Atrial Fibrillation, Neurocognitive Decline and Gene Expression After Cardiopulmonary Bypass

    PubMed Central

    Dalal, Rahul S.; Sabe, Ashraf A.; Elmadhun, Nassrene Y.; Ramlawi, Basel; Sellke, Frank W.

    2015-01-01

    OBJECTIVE Atrial fibrillation and neurocognitive decline are common complications after cardiopulmonary bypass. By utilizing genomic microarrays we investigate whether gene expression is associated with postoperative atrial fibrillation and neurocognitive decline. METHODS Twenty one cardiac surgery patients were prospectively matched and underwent neurocognitive assessments pre-operatively and four days postoperatively. The whole blood collected in the pre-cardiopulmonary bypass, 6 hours after-cardiopulmonary bypass, and on the 4th postoperative day was hybridized to Affymetrix Gene Chip U133 Plus 2.0 Microarrays. Gene expression in patients who developed postoperative atrial fibrillation and neurocognitive decline (n=6; POAF+NCD) was compared with gene expression in patients with postoperative atrial fibrillation and normal cognitive function (n=5; POAF+NORM) and patients with sinus rhythm and normal cognitive function (n=10; SR+NORM). Regulated genes were identified using JMP Genomics 4.0 with a false discovery rate of 0.05 and fold change of >1.5 or <-1.5. RESULTS Eleven patients developed postoperative atrial fibrillation. Six of these also developed neurocognitive decline. Of the 12 patients with sinus rhythm, only 2 developed neurocognitive decline. POAF+NCD patients had unique regulation of 17 named genes preoperatively, 60 named genes six hours after cardiopulmonary bypass, and 34 named genes four days postoperatively (P<0.05) compared with normal patients. Pathway analysis demonstrated that these genes are involved in cell death, inflammation, cardiac remodeling and nervous system function. CONCLUSION Patients who developed postoperative atrial fibrillation and neurocognitive decline after cardiopulmonary bypass may have differential genomic responses compared to normal patients and patients with only postoperative atrial fibrillation, suggesting common pathophysiology for these conditions. Further exploration of these genes may provide insight into the

  8. Gene expression analysis of precision-cut human liver slices indicates stable expression of ADME-Tox related genes

    SciTech Connect

    Elferink, M.G.L.; Olinga, P.; van Leeuwen, E.M.; Bauerschmidt, S.; Polman, J.; Schoonen, W.G.; Heisterkamp, S.H.; Groothuis, G.M.M.

    2011-05-15

    In the process of drug development it is of high importance to test the safety of new drugs with predictive value for human toxicity. A promising approach of toxicity testing is based on shifts in gene expression profiling of the liver. Toxicity screening based on animal liver cells cannot be directly extrapolated to humans due to species differences. The aim of this study was to evaluate precision-cut human liver slices as in vitro method for the prediction of human specific toxicity by toxicogenomics. The liver slices contain all cell types of the liver in their natural architecture. This is important since drug-induced toxicity often is a multi-cellular process. Previously we showed that toxicogenomic analysis of rat liver slices is highly predictive for rat in vivo toxicity. In this study we investigated the levels of gene expression during incubation up to 24 h with Affymetrix microarray technology. The analysis was focused on a broad spectrum of genes related to stress and toxicity, and on genes encoding for phase-I, -II and -III metabolizing enzymes and transporters. Observed changes in gene expression were associated with cytoskeleton remodeling, extracellular matrix and cell adhesion, but for the ADME-Tox related genes only minor changes were observed. PCA analysis showed that changes in gene expression were not associated with age, sex or source of the human livers. Slices treated with acetaminophen showed patterns of gene expression related to its toxicity. These results indicate that precision-cut human liver slices are relatively stable during 24 h of incubation and represent a valuable model for human in vitro hepatotoxicity testing despite the human inter-individual variability.

  9. Nonadditive gene expression in polyploids.

    PubMed

    Yoo, Mi-Jeong; Liu, Xiaoxian; Pires, J Chris; Soltis, Pamela S; Soltis, Douglas E

    2014-01-01

    Allopolyploidy involves hybridization and duplication of divergent parental genomes and provides new avenues for gene expression. The expression levels of duplicated genes in polyploids can show deviation from parental additivity (the arithmetic average of the parental expression levels). Nonadditive expression has been widely observed in diverse polyploids and comprises at least three possible scenarios: (a) The total gene expression level in a polyploid is similar to that of one of its parents (expression-level dominance); (b) total gene expression is lower or higher than in both parents (transgressive expression); and (c) the relative contribution of the parental copies (homeologs) to the total gene expression is unequal (homeolog expression bias). Several factors may result in expression nonadditivity in polyploids, including maternal-paternal influence, gene dosage balance, cis- and/or trans-regulatory networks, and epigenetic regulation. As our understanding of nonadditive gene expression in polyploids remains limited, a new generation of investigators should explore additional phenomena (i.e., alternative splicing) and use other high-throughput "omics" technologies to measure the impact of nonadditive expression on phenotype, proteome, and metabolome. PMID:25421600

  10. Gene expression analysis of tuberous sclerosis complex cortical tubers reveals increased expression of adhesion and inflammatory factors

    PubMed Central

    Boer, Karin; Crino, Peter B.; Gorter, Jan A.; Nellist, Mark; Jansen, Floor E.; Spliet, Wim G.M.; van Rijen, Peter C.; Wittink, Floyd R.A.; Breit, Timo M.; Troost, Dirk; Wadman, Wytse J.; Aronica, Eleonora

    2009-01-01

    Cortical tubers in patients with tuberous sclerosis complex are associated with disabling neurological manifestations, including intractable epilepsy. While these malformations are believed to result from the effects of TSC1 or TSC2 gene mutations, the molecular mechanisms leading to tuber formation, as well as the onset of seizures remain largely unknown. We used the Affymetrix Gene Chip platform to provide the first genome wide investigation of gene expression in surgically resected tubers, compared with histological normal perituberal tissue from the same patients or autopsy control tissue. We identified 2501 differentially expressed genes in cortical tubers compared with autopsy controls. Expression of genes associated with cell adhesion e.g., VCAM1, integrins and CD44, or with the inflammatory response, including complement factors, serpinA3, CCL2 and several cytokines, was increased in cortical tubers, whereas genes related to synaptic transmission e.g., the glial glutamate transporter GLT-1, and voltage-gated channel activity, exhibited lower expression. Gene expression in perituberal cortex was distinct from autopsy control cortex suggesting that even in the absence of tissue pathology the transcriptome is altered in TSC. Changes in gene expression yield insights into new candidate genes that may contribute to tuber formation or seizure onset, representing new targets for potential therapeutic development. PMID:19912235

  11. Evolution of Gene Expression after Gene Amplification

    PubMed Central

    Garcia, Nelson; Zhang, Wei; Wu, Yongrui; Messing, Joachim

    2015-01-01

    We took a rather unique approach to investigate the conservation of gene expression of prolamin storage protein genes across two different subfamilies of the Poaceae. We took advantage of oat plants carrying single maize chromosomes in different cultivars, called oat–maize addition (OMA) lines, which permitted us to determine whether regulation of gene expression was conserved between the two species. We found that γ-zeins are expressed in OMA7.06, which carries maize chromosome 7 even in the absence of the trans-acting maize prolamin-box-binding factor (PBF), which regulates their expression. This is likely because oat PBF can substitute for the function of maize PBF as shown in our transient expression data, using a γ-zein promoter fused to green fluorescent protein (GFP). Despite this conservation, the younger, recently amplified prolamin genes in maize, absent in oat, are not expressed in the corresponding OMAs. However, maize can express the oldest prolamin gene, the wheat high-molecular weight glutenin Dx5 gene, even when maize Pbf is knocked down (through PbfRNAi), and/or another maize transcription factor, Opaque-2 (O2) is knocked out (in maize o2 mutant). Therefore, older genes are conserved in their regulation, whereas younger ones diverged during evolution and eventually acquired a new repertoire of suitable transcriptional activators. PMID:25912045

  12. Serial analysis of gene expression.

    PubMed

    Velculescu, V E; Zhang, L; Vogelstein, B; Kinzler, K W

    1995-10-20

    The characteristics of an organism are determined by the genes expressed within it. A method was developed, called serial analysis of gene expression (SAGE), that allows the quantitative and simultaneous analysis of a large number of transcripts. To demonstrate this strategy, short diagnostic sequence tags were isolated from pancreas, concatenated, and cloned. Manual sequencing of 1000 tags revealed a gene expression pattern characteristic of pancreatic function. New pancreatic transcripts corresponding to novel tags were identified. SAGE should provide a broadly applicable means for the quantitative cataloging and comparison of expressed genes in a variety of normal, developmental, and disease states. PMID:7570003

  13. Whole Blood Gene Expression and Interleukin-6 Levels

    PubMed Central

    Lin, Honghuang; Joehanes, Roby; Pilling, Luke C.; Dupuis, Josée; Lunetta, Kathryn L.; Ying, Sai-Xia; Benjamin, Emelia J.; Hernandez, Dena; Singleton, Andrew; Melzer, David; Munson, Peter J.; Levy, Daniel; Ferrucci, Luigi; Murabito, Joanne M.

    2014-01-01

    Background Circulating interleukin-6 levels increase with advancing age and are a risk factor for various diseases and mortality. The characterization of gene expression profiles associated with interleukin-6 levels might suggest important molecular events underlying its regulation. Methods and Results We studied the association of transcriptional profiles with interleukin-6 levels in 2422 participants from Framingham Heart Study Offspring Cohort using Affymetrix Human Exon 1.0 ST Array. We identified 4139 genes that were significantly associated with interleukin-6 levels (FDR<0.05) after adjusting for age, sex and blood cell components. We then replicated 807 genes in the InCHIANTI study with 694 participants. Many of the top genes are involved in inflammation-related pathways or erythrocyte function, including JAK/Stat signaling pathway and interleukin-10 signaling pathway. Conclusion We identified and replicated 807 genes that were associated with circulating interleukin-6 levels. Future characterization of interleukin-6 regulation networks may facilitate the identification of additional potential targets for treating inflammation-related diseases. PMID:25311648

  14. Method of controlling gene expression

    DOEpatents

    Peters, Norman K.; Frost, John W.; Long, Sharon R.

    1991-12-03

    A method of controlling expression of a DNA segment under the control of a nod gene promoter which comprises administering to a host containing a nod gene promoter an amount sufficient to control expression of the DNA segment of a compound of the formula: ##STR1## in which each R is independently H or OH, is described.

  15. Gene expression and fractionation resistance

    PubMed Central

    2014-01-01

    Background Previous work on whole genome doubling in plants established the importance of gene functional category in provoking or suppressing duplicate gene loss, or fractionation. Other studies, particularly in Paramecium have correlated levels of gene expression with vulnerability or resistance to duplicate loss. Results Here we analyze the simultaneous effect of function category and expression in two plant data sets, rosids and asterids. Conclusion We demonstrate function category and expression level have independent effects, though expression does not play the dominant role it does in Paramecium. PMID:25573431

  16. Methods comparison for high-resolution transcriptional analysis of archival material on Affymetrix Plus 2.0 and Exon 1.0 microarrays.

    PubMed

    Linton, Kim; Hey, Yvonne; Dibben, Sian; Miller, Crispin; Freemont, Anthony; Radford, John; Pepper, Stuart

    2009-07-01

    Microarray gene expression profiling of formalin-fixed paraffin-embedded (FFPE) tissues is a new and evolving technique. This report compares transcript detection rates on Affymetrix U133 Plus 2.0 and Human Exon 1.0 ST GeneChips across several RNA extraction and target labeling protocols, using routinely collected archival FFPE samples. All RNA extraction protocols tested (Ambion-Optimum, Ambion-RecoverAll, and Qiagen-RNeasy FFPE) provided extracts suitable for microarray hybridization. Compared with Affymetrix One-Cycle labeled extracts, NuGEN system protocols utilizing oligo(dT) and random hexamer primers, and cDNA target preparations instead of cRNA, achieved percent present rates up to 55% on Plus 2.0 arrays. Based on two paired-sample analyses, at 90% specificity this equalled an average 30 percentage-point increase (from 50% to 80%) in FFPE transcript sensitivity relative to fresh frozen tissues, which we have assumed to have 100% sensitivity and specificity. The high content of Exon arrays, with multiple probe sets per exon, improved FFPE sensitivity to 92% at 96% specificity, corresponding to an absolute increase of ~600 genes over Plus 2.0 arrays. While larger series are needed to confirm high correspondence between fresh-frozen and FFPE expression patterns, these data suggest that both Plus 2.0 and Exon arrays are suitable platforms for FFPE microarray expression analyses.

  17. Evaluation of frozen tissue-derived prognostic gene expression signatures in FFPE colorectal cancer samples

    PubMed Central

    Zhu, Jing; Deane, Natasha G.; Lewis, Keeli B.; Padmanabhan, Chandrasekhar; Washington, M. Kay; Ciombor, Kristen K.; Timmers, Cynthia; Goldberg, Richard M.; Beauchamp, R. Daniel; Chen, Xi

    2016-01-01

    Defining molecular features that can predict the recurrence of colorectal cancer (CRC) for stage II-III patients remains challenging in cancer research. Most available clinical samples are Formalin-Fixed, Paraffin-Embedded (FFPE). NanoString nCounter® and Affymetrix GeneChip® Human Transcriptome Array 2.0 (HTA) are the two platforms marketed for high-throughput gene expression profiling for FFPE samples. In this study, to evaluate the gene expression of frozen tissue-derived prognostic signatures in FFPE CRC samples, we evaluated the expression of 516 genes from published frozen tissue-derived prognostic signatures in 42 FFPE CRC samples measured by both platforms. Based on HTA platform-derived data, we identified both gene (99 individual genes, FDR < 0.05) and gene set (four of the six reported multi-gene signatures with sufficient information for evaluation, P < 0.05) expression differences associated with survival outcomes. Using nCounter platform-derived data, one of the six multi-gene signatures (P < 0.05) but no individual gene was associated with survival outcomes. Our study indicated that sufficiently high quality RNA could be obtained from FFPE tumor tissues to detect frozen tissue-derived prognostic gene expression signatures for CRC patients. PMID:27623752

  18. Evaluation of frozen tissue-derived prognostic gene expression signatures in FFPE colorectal cancer samples.

    PubMed

    Zhu, Jing; Deane, Natasha G; Lewis, Keeli B; Padmanabhan, Chandrasekhar; Washington, M Kay; Ciombor, Kristen K; Timmers, Cynthia; Goldberg, Richard M; Beauchamp, R Daniel; Chen, Xi

    2016-01-01

    Defining molecular features that can predict the recurrence of colorectal cancer (CRC) for stage II-III patients remains challenging in cancer research. Most available clinical samples are Formalin-Fixed, Paraffin-Embedded (FFPE). NanoString nCounter® and Affymetrix GeneChip® Human Transcriptome Array 2.0 (HTA) are the two platforms marketed for high-throughput gene expression profiling for FFPE samples. In this study, to evaluate the gene expression of frozen tissue-derived prognostic signatures in FFPE CRC samples, we evaluated the expression of 516 genes from published frozen tissue-derived prognostic signatures in 42 FFPE CRC samples measured by both platforms. Based on HTA platform-derived data, we identified both gene (99 individual genes, FDR < 0.05) and gene set (four of the six reported multi-gene signatures with sufficient information for evaluation, P < 0.05) expression differences associated with survival outcomes. Using nCounter platform-derived data, one of the six multi-gene signatures (P < 0.05) but no individual gene was associated with survival outcomes. Our study indicated that sufficiently high quality RNA could be obtained from FFPE tumor tissues to detect frozen tissue-derived prognostic gene expression signatures for CRC patients. PMID:27623752

  19. Gene expression profiles in peripheral lymphocytes by arsenic exposure and skin lesion status in a Bangladeshi population.

    PubMed

    Argos, Maria; Kibriya, Muhammad G; Parvez, Faruque; Jasmine, Farzana; Rakibuz-Zaman, Muhammad; Ahsan, Habibul

    2006-07-01

    Millions of individuals worldwide are chronically exposed to arsenic through their drinking water. In this study, the effect of arsenic exposure and arsenical skin lesion status on genome-wide gene expression patterns was evaluated using RNA from peripheral blood lymphocytes of individuals selected from the Health Effects of Arsenic Longitudinal Study. Affymetrix HG-U133A GeneChip (Affymetrix, Santa Clara, CA) arrays were used to measure the expression of approximately 22,000 transcripts. Our primary statistical analysis involved identifying differentially expressed genes between participants with and without arsenical skin lesions based on the significance analysis of microarrays statistic with an a priori defined 1% false discovery rate to minimize false positives. To better characterize differential expression, we also conducted Gene Ontology and pathway comparisons in addition to the gene-specific analyses. Four-hundred sixty-eight genes were differentially expressed between these two groups, from which 312 differentially expressed genes were identified by restricting the analysis to female never-smokers. We also explored possible differential gene expression by arsenic exposure levels among individuals without manifest arsenical skin lesions; however, no differentially expressed genes could be identified from this comparison. Our findings show that microarray-based gene expression analysis is a powerful method to characterize the molecular profile of arsenic exposure and arsenic-induced diseases. Genes identified from this analysis may provide insights into the underlying processes of arsenic-induced disease and represent potential targets for chemoprevention studies to reduce arsenic-induced skin cancer in this population.

  20. Gene expression profiling in response to the histone deacetylase inhibitor BL1521 in neuroblastoma

    SciTech Connect

    Ruijter, Annemieke J.M. de; Kemp, Stephan . E-mail: a.b.vankuilenburg@amc.uva.nl

    2005-10-01

    Neuroblastoma is a childhood tumor with a poor survival in advanced stage disease despite intensive chemotherapeutic regimes. The new histone deacetylase (HDAC) inhibitor BL1521 has shown promising results in neuroblastoma. Inhibition of HDAC resulted in a decrease in proliferation and metabolic activity, induction of apoptosis and differentiation of neuroblastoma cells. In order to elucidate the mechanism mediating the effects of BL1521 on neuroblastoma cells, we investigated the gene expression profile of an MYCN single copy (SKNAS) and an MYCN amplified (IMR32) neuroblastoma cell line after treatment with BL1521 using the Affymetrix oligonucleotide array U133A. An altered expression of 255 genes was observed in both neuroblastoma cell lines. The majority of these genes were involved in gene expression, cellular metabolism, and cell signaling. We observed changes in the expression of vital genes belonging to the cell cycle (cyclin D1 and CDK4) and apoptosis (BNIP3, BID, and BCL2) pathway in response to BL1521. The expression of 37 genes was altered by both BL1521 and Trichostatin A, which could indicate a common gene set regulated by different HDAC inhibitors. BL1521 treatment changed the expression of a number of MYCN-associated genes. Several genes in the Wnt and the Delta/Notch pathways were changed in response to BL1521 treatment, suggesting that BL1521 is able to induce the differentiation of neuroblastoma cells into a more mature phenotype.

  1. DGEM--a microarray gene expression database for primary human disease tissues.

    PubMed

    Xia, Yuni; Campen, Andrew; Rigsby, Dan; Guo, Ying; Feng, Xingdong; Su, Eric W; Palakal, Mathew; Li, Shuyu

    2007-01-01

    Gene expression patterns can reflect gene regulations in human tissues under normal or pathologic conditions. Gene expression profiling data from studies of primary human disease samples are particularly valuable since these studies often span many years in order to collect patient clinical information and achieve a large sample size. Disease-to-Gene Expression Mapper (DGEM) provides a beneficial community resource to access and analyze these data; it currently includes Affymetrix oligonucleotide array datasets for more than 40 human diseases and 1400 samples. The data are normalized to the same scale and stored in a relational database. A statistical-analysis pipeline was implemented to identify genes abnormally expressed in disease tissues or genes whose expressions are associated with clinical parameters such as cancer patient survival. Data-mining results can be queried through a web-based interface at http://dgem.dhcp.iupui.edu/. The query tool enables dynamic generation of graphs and tables that are further linked to major gene and pathway resources that connect the data to relevant biology, including Entrez Gene and Kyoto Encyclopedia of Genes and Genomes (KEGG). In summary, DGEM provides scientists and physicians a valuable tool to study disease mechanisms, to discover potential disease biomarkers for diagnosis and prognosis, and to identify novel gene targets for drug discovery. The source code is freely available for non-profit use, on request to the authors. PMID:17570735

  2. Regulation of Neuronal Gene Expression

    NASA Astrophysics Data System (ADS)

    Thiel, Gerald; Lietz, Michael; Leichter, Michael

    Humans as multicellular organisms contain a variety of different cell types where each cell population must fulfill a distinct function in the interest of the whole organism. The molecular basis for the variations in morphology, biochemistry, molecular biology, and function of the various cell types is the cell-type specific expression of genes. These genes encode proteins necessary for executing the specialized functions of each cell type within an organism. We describe here a regulatory mechanism for the expression of neuronal genes. The zinc finger protein REST binds to the regulatory region of many neuronal genes and represses neuronal gene expression in nonneuronal tissues. A negative regulatory mechanism, involving a transcriptional repressor, seems to play an important role in establishing the neuronal phenotype.

  3. affyPara-a Bioconductor Package for Parallelized Preprocessing Algorithms of Affymetrix Microarray Data.

    PubMed

    Schmidberger, Markus; Vicedo, Esmeralda; Mansmann, Ulrich

    2009-07-22

    Microarray data repositories as well as large clinical applications of gene expression allow to analyse several hundreds of microarrays at one time. The preprocessing of large amounts of microarrays is still a challenge. The algorithms are limited by the available computer hardware. For example, building classification or prognostic rules from large microarray sets will be very time consuming. Here, preprocessing has to be a part of the cross-validation and resampling strategy which is necessary to estimate the rule's prediction quality honestly.This paper proposes the new Bioconductor package affyPara for parallelized preprocessing of Affymetrix microarray data. Partition of data can be applied on arrays and parallelization of algorithms is a straightforward consequence. The partition of data and distribution to several nodes solves the main memory problems and accelerates preprocessing by up to the factor 20 for 200 or more arrays.affyPara is a free and open source package, under GPL license, available form the Bioconductor project at www.bioconductor.org. A user guide and examples are provided with the package.

  4. Impact of Statins on Gene Expression in Human Lung Tissues

    PubMed Central

    Lane, Jérôme; van Eeden, Stephan F.; Obeidat, Ma’en; Sin, Don D.; Tebbutt, Scott J.; Timens, Wim; Postma, Dirkje S.; Laviolette, Michel; Paré, Peter D.; Bossé, Yohan

    2015-01-01

    Statins are 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors that alter the synthesis of cholesterol. Some studies have shown a significant association of statins with improved respiratory health outcomes of patients with asthma, chronic obstructive pulmonary disease and lung cancer. Here we hypothesize that statins impact gene expression in human lungs and may reveal the pleiotropic effects of statins that are taking place directly in lung tissues. Human lung tissues were obtained from patients who underwent lung resection or transplantation. Gene expression was measured on a custom Affymetrix array in a discovery cohort (n = 408) and two replication sets (n = 341 and 282). Gene expression was evaluated by linear regression between statin users and non-users, adjusting for age, gender, smoking status, and other covariables. The results of each cohort were combined in a meta-analysis and biological pathways were studied using Gene Set Enrichment Analysis. The discovery set included 141 statin users. The lung mRNA expression levels of eighteen and three genes were up-regulated and down-regulated in statin users (FDR < 0.05), respectively. Twelve of the up-regulated genes were replicated in the first replication set, but none in the second (p-value < 0.05). Combining the discovery and replication sets into a meta-analysis improved the significance of the 12 up-regulated genes, which includes genes encoding enzymes and membrane proteins involved in cholesterol biosynthesis. Canonical biological pathways altered by statins in the lung include cholesterol, steroid, and terpenoid backbone biosynthesis. No genes encoding inflammatory, proteases, pro-fibrotic or growth factors were altered by statins, suggesting that the direct effect of statin in the lung do not go beyond its antilipidemic action. Although more studies are needed with specific lung cell types and different classes and doses of statins, the improved health outcomes and survival observed in statin

  5. Microgravity and Immunity: Changes in Lymphocyte Gene Expression

    NASA Technical Reports Server (NTRS)

    Risin, D.; Pellis, N. R.; Ward, N. E.; Risin, S. A.

    2006-01-01

    Earlier studies had shown that modeled and true microgravity (MG) cause multiple direct effects on human lymphocytes. MG inhibits lymphocyte locomotion, suppresses polyclonal and antigen-specific activation, affects signal transduction mechanisms, as well as activation-induced apoptosis. In this study we assessed changes in gene expression associated with lymphocyte exposure to microgravity in an attempt to identify microgravity-sensitive genes (MGSG) in general and specifically those genes that might be responsible for the functional and structural changes observed earlier. Two sets of experiments targeting different goals were conducted. In the first set, T-lymphocytes from normal donors were activated with antiCD3 and IL2 and then cultured in 1g (static) and modeled MG (MMG) conditions (Rotating Wall Vessel bioreactor) for 24 hours. This setting allowed searching for MGSG by comparison of gene expression patterns in zero and 1 g gravity. In the second set - activated T-cells after culturing for 24 hours in 1g and MMG were exposed three hours before harvesting to a secondary activation stimulus (PHA) thus triggering the apoptotic pathway. Total RNA was extracted using the RNeasy isolation kit (Qiagen, Valencia, CA). Affymetrix Gene Chips (U133A), allowing testing for 18,400 human genes, were used for microarray analysis. In the first set of experiments MMG exposure resulted in altered expression of 89 genes, 10 of them were up-regulated and 79 down-regulated. In the second set, changes in expression were revealed in 85 genes, 20 were up-regulated and 65 were down-regulated. The analysis revealed that significant numbers of MGS genes are associated with signal transduction and apoptotic pathways. Interestingly, the majority of genes that responded by up- or down-regulation in the alternative sets of experiments were not the same, possibly reflecting different functional states of the examined T-lymphocyte populations. The responder genes (MGSG) might play an

  6. Analysis of the gene expression profile of mouse male meiotic germ cells.

    PubMed

    Rossi, Pellegrino; Dolci, Susanna; Sette, Claudio; Capolunghi, Federica; Pellegrini, Manuela; Loiarro, Maria; Di Agostino, Silvia; Paronetto, Maria Paola; Grimaldi, Paola; Merico, Daniele; Martegani, Enzo; Geremia, Raffaele

    2004-05-01

    Wide genome analysis of difference in gene expression between spermatogonial populations from 7-day-old mice and pachytene spermatocytes from 18-day-old mice was performed using Affymetrix gene chips representing approximately 12,500 mouse known genes or EST sequences, spanning approximately 1/3rd of the mouse genome. To delineate differences in the profile of gene expression between mitotic and meiotic stages of male germ cell differentiation, expressed genes were grouped in functional clusters. The analysis confirmed the previously described pre-meiotic or meiotic expression for several genes, in particular for those involved in the regulation of the mitotic and meiotic cell cycle, and for those whose transcripts are accumulated during the meiotic stages to be translated later in post-meiotic stages. Differential expression of several additional genes was discovered. In few cases (pro-apoptotic factors Bak, Bad and Bax), data were in conflict with the previously published stage-dependent expression of genes already known to be expressed in male germ cells. Northern blot analysis of selected genes confirmed the results obtained with the microarray chips. Six of these were novel genes specifically expressed in pachytene spermatocytes: a chromatin remodeling factor (chrac1/YCL1), a homeobox gene (hmx1), a novel G-coupled receptor for an unknown ligand (Gpr19), a glycoprotein of the intestinal epithelium (mucin 3), a novel RAS activator (Ranbp9), and the A630056B21Rik gene (predicted to encode a novel zinc finger protein). These studies will help to delineate the global patterns of gene expression characterizing male germ cell differentiation for a better understanding of regulation of spermatogenesis in mammals.

  7. Genome-wide age-related changes in DNA methylation and gene expression in human PBMCs.

    PubMed

    Steegenga, Wilma T; Boekschoten, Mark V; Lute, Carolien; Hooiveld, Guido J; de Groot, Philip J; Morris, Tiffany J; Teschendorff, Andrew E; Butcher, Lee M; Beck, Stephan; Müller, Michael

    2014-06-01

    Aging is a progressive process that results in the accumulation of intra- and extracellular alterations that in turn contribute to a reduction in health. Age-related changes in DNA methylation have been reported before and may be responsible for aging-induced changes in gene expression, although a causal relationship has yet to be shown. Using genome-wide assays, we analyzed age-induced changes in DNA methylation and their effect on gene expression with and without transient induction with the synthetic transcription modulating agent WY14,643. To demonstrate feasibility of the approach, we isolated peripheral blood mononucleated cells (PBMCs) from five young and five old healthy male volunteers and cultured them with or without WY14,643. Infinium 450K BeadChip and Affymetrix Human Gene 1.1 ST expression array analysis revealed significant differential methylation of at least 5 % (ΔYO > 5 %) at 10,625 CpG sites between young and old subjects, but only a subset of the associated genes were also differentially expressed. Age-related differential methylation of previously reported epigenetic biomarkers of aging including ELOVL2, FHL2, PENK, and KLF14 was confirmed in our study, but these genes did not display an age-related change in gene expression in PBMCs. Bioinformatic analysis revealed that differentially methylated genes that lack an age-related expression change predominantly represent genes involved in carcinogenesis and developmental processes, and expression of most of these genes were silenced in PBMCs. No changes in DNA methylation were found in genes displaying transiently induced changes in gene expression. In conclusion, aging-induced differential methylation often targets developmental genes and occurs mostly without change in gene expression.

  8. Genome-wide age-related changes in DNA methylation and gene expression in human PBMCs.

    PubMed

    Steegenga, Wilma T; Boekschoten, Mark V; Lute, Carolien; Hooiveld, Guido J; de Groot, Philip J; Morris, Tiffany J; Teschendorff, Andrew E; Butcher, Lee M; Beck, Stephan; Müller, Michael

    2014-06-01

    Aging is a progressive process that results in the accumulation of intra- and extracellular alterations that in turn contribute to a reduction in health. Age-related changes in DNA methylation have been reported before and may be responsible for aging-induced changes in gene expression, although a causal relationship has yet to be shown. Using genome-wide assays, we analyzed age-induced changes in DNA methylation and their effect on gene expression with and without transient induction with the synthetic transcription modulating agent WY14,643. To demonstrate feasibility of the approach, we isolated peripheral blood mononucleated cells (PBMCs) from five young and five old healthy male volunteers and cultured them with or without WY14,643. Infinium 450K BeadChip and Affymetrix Human Gene 1.1 ST expression array analysis revealed significant differential methylation of at least 5 % (ΔYO > 5 %) at 10,625 CpG sites between young and old subjects, but only a subset of the associated genes were also differentially expressed. Age-related differential methylation of previously reported epigenetic biomarkers of aging including ELOVL2, FHL2, PENK, and KLF14 was confirmed in our study, but these genes did not display an age-related change in gene expression in PBMCs. Bioinformatic analysis revealed that differentially methylated genes that lack an age-related expression change predominantly represent genes involved in carcinogenesis and developmental processes, and expression of most of these genes were silenced in PBMCs. No changes in DNA methylation were found in genes displaying transiently induced changes in gene expression. In conclusion, aging-induced differential methylation often targets developmental genes and occurs mostly without change in gene expression. PMID:24789080

  9. Differential gene expression in pulmonary artery endothelial cells exposed to sickle cell plasma.

    PubMed

    Klings, Elizabeth S; Safaya, Surinder; Adewoye, Adeboye H; Odhiambo, Adam; Frampton, Garrett; Lenburg, Marc; Gerry, Norman; Sebastiani, Paola; Steinberg, Martin H; Farber, Harrison W

    2005-05-11

    Clinical variability in sickle cell disease (SCD) suggests a role for extra-erythrocytic factors in the pathogenesis of vasoocclusion. We hypothesized that endothelial cell (EC) dysfunction, one possible modifier of disease variability, results from induction of phenotypic changes by circulating factors. Accordingly, we analyzed gene expression in cultured human pulmonary artery ECs (HPAEC) exposed to plasma from 1) sickle acute chest syndrome (ACS) patients, 2) SCD patients at steady state, 3) normal volunteers, and 4) serum-free media, using whole genome microarrays (U133A-B GeneChip, Affymetrix). Data were analyzed by Bayesian analysis of differential gene expression (BADGE). Differential expression was defined by the probability of >1.5 fold change in signal intensity greater than 0.999 and a predicted score of 70-100, measured by cross-validation. Compared with normal plasma, plasma from SCD patients (steady state) resulted in differential expression of 50 genes in HPAEC. Of these genes, molecules involved in cholesterol biosynthesis and lipid transport, the cellular stress response, and extracellular matrix proteins were most prominent. Another 58 genes were differentially expressed in HPAEC exposed to plasma from ACS patients. The pattern of altered gene expression suggests that plasma from SCD patients induces an EC phenotype which is anti-apoptotic and favors cholesterol biosynthesis. An altered EC phenotype elicited by SCD plasma may contribute to the pathogenesis of sickle vasoocclusion.

  10. A new method for class prediction based on signed-rank algorithms applied to Affymetrix® microarray experiments

    PubMed Central

    Rème, Thierry; Hose, Dirk; De Vos, John; Vassal, Aurélien; Poulain, Pierre-Olivier; Pantesco, Véronique; Goldschmidt, Hartmut; Klein, Bernard

    2008-01-01

    Background The huge amount of data generated by DNA chips is a powerful basis to classify various pathologies. However, constant evolution of microarray technology makes it difficult to mix data from different chip types for class prediction of limited sample populations. Affymetrix® technology provides both a quantitative fluorescence signal and a decision (detection call: absent or present) based on signed-rank algorithms applied to several hybridization repeats of each gene, with a per-chip normalization. We developed a new prediction method for class belonging based on the detection call only from recent Affymetrix chip type. Biological data were obtained by hybridization on U133A, U133B and U133Plus 2.0 microarrays of purified normal B cells and cells from three independent groups of multiple myeloma (MM) patients. Results After a call-based data reduction step to filter out non class-discriminative probe sets, the gene list obtained was reduced to a predictor with correction for multiple testing by iterative deletion of probe sets that sequentially improve inter-class comparisons and their significance. The error rate of the method was determined using leave-one-out and 5-fold cross-validation. It was successfully applied to (i) determine a sex predictor with the normal donor group classifying gender with no error in all patient groups except for male MM samples with a Y chromosome deletion, (ii) predict the immunoglobulin light and heavy chains expressed by the malignant myeloma clones of the validation group and (iii) predict sex, light and heavy chain nature for every new patient. Finally, this method was shown powerful when compared to the popular classification method Prediction Analysis of Microarray (PAM). Conclusion This normalization-free method is routinely used for quality control and correction of collection errors in patient reports to clinicians. It can be easily extended to multiple class prediction suitable with clinical groups, and looks

  11. VTCdb: a gene co-expression database for the crop species Vitis vinifera (grapevine)

    PubMed Central

    2013-01-01

    Background Gene expression datasets in model plants such as Arabidopsis have contributed to our understanding of gene function and how a single underlying biological process can be governed by a diverse network of genes. The accumulation of publicly available microarray data encompassing a wide range of biological and environmental conditions has enabled the development of additional capabilities including gene co-expression analysis (GCA). GCA is based on the understanding that genes encoding proteins involved in similar and/or related biological processes may exhibit comparable expression patterns over a range of experimental conditions, developmental stages and tissues. We present an open access database for the investigation of gene co-expression networks within the cultivated grapevine, Vitis vinifera. Description The new gene co-expression database, VTCdb (http://vtcdb.adelaide.edu.au/Home.aspx), offers an online platform for transcriptional regulatory inference in the cultivated grapevine. Using condition-independent and condition-dependent approaches, grapevine co-expression networks were constructed using the latest publicly available microarray datasets from diverse experimental series, utilising the Affymetrix Vitis vinifera GeneChip (16 K) and the NimbleGen Grape Whole-genome microarray chip (29 K), thus making it possible to profile approximately 29,000 genes (95% of the predicted grapevine transcriptome). Applications available with the online platform include the use of gene names, probesets, modules or biological processes to query the co-expression networks, with the option to choose between Affymetrix or Nimblegen datasets and between multiple co-expression measures. Alternatively, the user can browse existing network modules using interactive network visualisation and analysis via CytoscapeWeb. To demonstrate the utility of the database, we present examples from three fundamental biological processes (berry development, photosynthesis and

  12. Identification of Potential Anticancer Activities of Novel Ganoderma lucidum Extracts Using Gene Expression and Pathway Network Analysis.

    PubMed

    Kao, Chi H J; Bishop, Karen S; Xu, Yuanye; Han, Dug Yeo; Murray, Pamela M; Marlow, Gareth J; Ferguson, Lynnette R

    2016-01-01

    Ganoderma lucidum (lingzhi) has been used for the general promotion of health in Asia for many centuries. The common method of consumption is to boil lingzhi in water and then drink the liquid. In this study, we examined the potential anticancer activities of G. lucidum submerged in two commonly consumed forms of alcohol in East Asia: malt whiskey and rice wine. The anticancer effect of G. lucidum, using whiskey and rice wine-based extraction methods, has not been previously reported. The growth inhibition of G. lucidum whiskey and rice wine extracts on the prostate cancer cell lines, PC3 and DU145, was determined. Using Affymetrix gene expression assays, several biologically active pathways associated with the anticancer activities of G. lucidum extracts were identified. Using gene expression analysis (real-time polymerase chain reaction [RT-PCR]) and protein analysis (Western blotting), we confirmed the expression of key genes and their associated proteins that were initially identified with Affymetrix gene expression analysis. PMID:27006591

  13. Identification of Potential Anticancer Activities of Novel Ganoderma lucidum Extracts Using Gene Expression and Pathway Network Analysis

    PubMed Central

    Kao, Chi H.J.; Bishop, Karen S.; Xu, Yuanye; Han, Dug Yeo; Murray, Pamela M.; Marlow, Gareth J.; Ferguson, Lynnette R.

    2016-01-01

    Ganoderma lucidum (lingzhi) has been used for the general promotion of health in Asia for many centuries. The common method of consumption is to boil lingzhi in water and then drink the liquid. In this study, we examined the potential anticancer activities of G. lucidum submerged in two commonly consumed forms of alcohol in East Asia: malt whiskey and rice wine. The anticancer effect of G. lucidum, using whiskey and rice wine-based extraction methods, has not been previously reported. The growth inhibition of G. lucidum whiskey and rice wine extracts on the prostate cancer cell lines, PC3 and DU145, was determined. Using Affymetrix gene expression assays, several biologically active pathways associated with the anticancer activities of G. lucidum extracts were identified. Using gene expression analysis (real-time polymerase chain reaction [RT-PCR]) and protein analysis (Western blotting), we confirmed the expression of key genes and their associated proteins that were initially identified with Affymetrix gene expression analysis. PMID:27006591

  14. Genome-wide analysis in human colorectal cancer cells reveals ischemia-mediated expression of motility genes via DNA hypomethylation.

    PubMed

    Skowronski, Karolina; Skowronki, Karolina; Andrews, Joseph; Rodenhiser, David I; Coomber, Brenda L

    2014-01-01

    DNA hypomethylation is an important epigenetic modification found to occur in many different cancer types, leading to the upregulation of previously silenced genes and loss of genomic stability. We previously demonstrated that hypoxia and hypoglycaemia (ischemia), two common micro-environmental changes in solid tumours, decrease DNA methylation through the downregulation of DNMTs in human colorectal cancer cells. Here, we utilized a genome-wide cross-platform approach to identify genes hypomethylated and upregulated by ischemia. Following exposure to hypoxia or hypoglycaemia, methylated DNA from human colorectal cancer cells (HCT116) was immunoprecipitated and analysed with an Affymetrix promoter array. Additionally, RNA was isolated and analysed in parallel with an Affymetrix expression array. Ingenuity pathway analysis software revealed that a significant proportion of the genes hypomethylated and upregulated were involved in cellular movement, including PLAUR and CYR61. A Matrigel invasion assay revealed that indeed HCT116 cells grown in hypoxic or hypoglycaemic conditions have increased mobility capabilities. Confirmation of upregulated expression of cellular movement genes was performed with qPCR. The correlation between ischemia and metastasis is well established in cancer progression, but the molecular mechanisms responsible for this common observation have not been clearly identified. Our novel data suggests that hypoxia and hypoglycaemia may be driving changes in DNA methylation through downregulation of DNMTs. This is the first report to our knowledge that provides an explanation for the increased metastatic potential seen in ischemic cells; i.e. that ischemia could be driving DNA hypomethylation and increasing expression of cellular movement genes.

  15. Establishment of the Lotus japonicus Gene Expression Atlas (LjGEA) and its use to explore legume seed maturation.

    PubMed

    Verdier, Jerome; Torres-Jerez, Ivone; Wang, Mingyi; Andriankaja, Andry; Allen, Stacy N; He, Ji; Tang, Yuhong; Murray, Jeremy D; Udvardi, Michael K

    2013-04-01

    Lotus japonicus is a model species for legume genomics. To accelerate legume functional genomics, we developed a Lotus japonicus Gene Expression Atlas (LjGEA), which provides a global view of gene expression in all organ systems of this species, including roots, nodules, stems, petioles, leaves, flowers, pods and seeds. Time-series data covering multiple stages of developing pod and seed are included in the LjGEA. In addition, previously published L. japonicus Affymetrix data are included in the database, making it a 'one-stop shop' for transcriptome analysis of this species. The LjGEA web server (http://ljgea.noble.org/) enables flexible, multi-faceted analyses of the transcriptome. Transcript data may be accessed using the Affymetrix probe identification number, DNA sequence, gene name, functional description in natural language, and GO and KEGG annotation terms. Genes may be discovered through co-expression or differential expression analysis. Users may select a subset of experiments and visualize and compare expression profiles of multiple genes simultaneously. Data may be downloaded in a tabular form compatible with common analytical and visualization software. To illustrate the power of LjGEA, we explored the transcriptome of developing seeds. Genes represented by 36 474 probe sets were expressed at some stage during seed development, and almost half of these genes displayed differential expression during development. Among the latter were 624 transcription factor genes, some of which are orthologs of transcription factor genes that are known to regulate seed development in other species, while most are novel and represent attractive targets for reverse genetics approaches to determine their roles in this important organ.

  16. Gene expression of sternohyoid and diaphragm muscles in type 2 diabetic rats

    PubMed Central

    2013-01-01

    Background Type 2 diabetes differs from type 1 diabetes in its pathogenesis. Type 1 diabetic diaphragm has altered gene expression which includes lipid and carbohydrate metabolism, ubiquitination and oxidoreductase activity. The objectives of the present study were to assess respiratory muscle gene expression changes in type 2 diabetes and to determine whether they are greater for the diaphragm than an upper airway muscle. Methods Diaphragm and sternohyoid muscle from Zucker diabetic fatty (ZDF) rats were analyzed with Affymetrix gene expression arrays. Results The two muscles had 97 and 102 genes, respectively, with at least ± 1.5-fold significantly changed expression with diabetes, and these were assigned to gene ontology groups based on over-representation analysis. Several significantly changed groups were common to both muscles, including lipid metabolism, carbohydrate metabolism, muscle contraction, ion transport and collagen, although the number of genes and the specific genes involved differed considerably for the two muscles. In both muscles there was a shift in metabolism gene expression from carbohydrate metabolism toward lipid metabolism, but the shift was greater and involved more genes in diabetic diaphragm than diabetic sternohyoid muscle. Groups present in only diaphragm were blood circulation and oxidoreductase activity. Groups present in only sternohyoid were immune & inflammation and response to stress & wounding, with complement genes being a prominent component. Conclusion Type 2 diabetes-induced gene expression changes in respiratory muscles has both similarities and differences relative to previous data on type 1 diabetes gene expression. Furthermore, the diabetic alterations in gene expression differ between diaphragm and sternohyoid. PMID:24199937

  17. Nutritional regulation of gene expression.

    PubMed

    Cousins, R J

    1999-01-25

    Genes are regulated by complex arrays of response elements that influence the rate of transcription. Nutrients and hormones either act directly to influence these rates or act indirectly through specialized signaling pathways. Metabolites of vitamins A and D, fatty acids, some sterols, and zinc are among the nutrients that influence transcription directly. Components of dietary fiber may influence gene expression indirectly through changes in hormonal signaling, mechanical stimuli, and metabolites produced by the intestinal microflora. In addition, consumption of water-soluble fibers may lead to changes in gene expression mediated through indirect mechanisms that influence transcription rates. In the large intestine, short-chain fatty acids, including butyric acid, are produced by microflora. Butyric acid can indirectly influence gene expression. Some sources of fiber limit nutrient absorption, particularly of trace elements. This could have direct or indirect effects on gene expression. Identification of genes in colonic epithelial cells that are differentially regulated by dietary fiber will be an important step toward understanding the role of dietary factors in colorectal cancer progression.

  18. Circadian variations in gene expression in rat abdominal adipose tissue and relationship to physiology

    PubMed Central

    Sukumaran, Siddharth; Xue, Bai; Jusko, William J.; DuBois, Debra C.

    2010-01-01

    Circadian rhythms occur in all levels of organization from expression of genes to complex physiological processes. Although much is known about the mechanism of the central clock in the suprachiasmatic nucleus, the regulation of clocks present in peripheral tissues as well as the genes regulated by those clocks is still unclear. In this study, the circadian regulation of gene expression was examined in rat adipose tissue. A rich time series involving 54 animals euthanized at 18 time points within the 24-h cycle (12:12 h light-dark) was performed. mRNA expression was examined with Affymetrix gene array chips and quantitative real-time PCR, along with selected physiological measurements. Transcription factors involved in the regulation of central rhythms were examined, and 13 showed circadian oscillations. Mining of microarray data identified 190 probe sets that showed robust circadian oscillations. Circadian regulated probe sets were further parsed into seven distinct temporal clusters, with >70% of the genes showing maximum expression during the active/dark period. These genes were grouped into eight functional categories, which were examined within the context of their temporal expression. Circadian oscillations were also observed in plasma leptin, corticosterone, insulin, glucose, triglycerides, free fatty acids, and LDL cholesterol. Circadian oscillation in these physiological measurements along with the functional categorization of these genes suggests an important role for circadian rhythms in controlling various functions in white adipose tissue including adipogenesis, energy metabolism, and immune regulation. PMID:20682845

  19. Bronchial airway gene expression in smokers with lung or head and neck cancer

    PubMed Central

    Van Dyck, Eric; Nazarov, Petr V; Muller, Arnaud; Nicot, Nathalie; Bosseler, Manon; Pierson, Sandrine; Van Moer, Kris; Palissot, Valérie; Mascaux, Céline; Knolle, Ulrich; Ninane, Vincent; Nati, Romain; Bremnes, Roy M; Vallar, Laurent; Berchem, Guy; Schlesser, Marc

    2014-01-01

    Cigarette smoking is the major cause of cancers of the respiratory tract, including non-small cell lung cancer (NSCLC) and head and neck cancer (HNC). In order to better understand carcinogenesis of the lung and upper airways, we have compared the gene expression profiles of tumor-distant, histologically normal bronchial biopsy specimens obtained from current smokers with NSCLC or HNC (SC, considered as a single group), as well as nonsmokers (NS) and smokers without cancer (SNC). RNA from a total of 97 biopsies was used for gene expression profiling (Affymetrix HG-U133 Plus 2.0 array). Differentially expressed genes were used to compare NS, SNC, and SC, and functional analysis was carried out using Ingenuity Pathway Analysis (IPA). Smoking-related cancer of the respiratory tract was found to affect the expression of genes encoding xenobiotic biotransformation proteins, as well as proteins associated with crucial inflammation/immunity pathways and other processes that protect the airway from the chemicals in cigarette smoke or contribute to carcinogenesis. Finally, we used the prediction analysis for microarray (PAM) method to identify gene signatures of cigarette smoking and cancer, and uncovered a 15-gene signature that distinguished between SNC and SC with an accuracy of 83%. Thus, gene profiling of histologically normal bronchial biopsy specimens provided insight into cigarette-induced carcinogenesis of the respiratory tract and gene signatures of cancer in smokers. PMID:24497500

  20. Transgenic Arabidopsis Gene Expression System

    NASA Technical Reports Server (NTRS)

    Ferl, Robert; Paul, Anna-Lisa

    2009-01-01

    The Transgenic Arabidopsis Gene Expression System (TAGES) investigation is one in a pair of investigations that use the Advanced Biological Research System (ABRS) facility. TAGES uses Arabidopsis thaliana, thale cress, with sensor promoter-reporter gene constructs that render the plants as biomonitors (an organism used to determine the quality of the surrounding environment) of their environment using real-time nondestructive Green Fluorescent Protein (GFP) imagery and traditional postflight analyses.

  1. Zipf's Law in Gene Expression

    NASA Astrophysics Data System (ADS)

    Furusawa, Chikara; Kaneko, Kunihiko

    2003-02-01

    Using data from gene expression databases on various organisms and tissues, including yeast, nematodes, human normal and cancer tissues, and embryonic stem cells, we found that the abundances of expressed genes exhibit a power-law distribution with an exponent close to -1; i.e., they obey Zipf’s law. Furthermore, by simulations of a simple model with an intracellular reaction network, we found that Zipf’s law of chemical abundance is a universal feature of cells where such a network optimizes the efficiency and faithfulness of self-reproduction. These findings provide novel insights into the nature of the organization of reaction dynamics in living cells.

  2. Neighboring Genes Show Correlated Evolution in Gene Expression.

    PubMed

    Ghanbarian, Avazeh T; Hurst, Laurence D

    2015-07-01

    When considering the evolution of a gene's expression profile, we commonly assume that this is unaffected by its genomic neighborhood. This is, however, in contrast to what we know about the lack of autonomy between neighboring genes in gene expression profiles in extant taxa. Indeed, in all eukaryotic genomes genes of similar expression-profile tend to cluster, reflecting chromatin level dynamics. Does it follow that if a gene increases expression in a particular lineage then the genomic neighbors will also increase in their expression or is gene expression evolution autonomous? To address this here we consider evolution of human gene expression since the human-chimp common ancestor, allowing for both variation in estimation of current expression level and error in Bayesian estimation of the ancestral state. We find that in all tissues and both sexes, the change in gene expression of a focal gene on average predicts the change in gene expression of neighbors. The effect is highly pronounced in the immediate vicinity (<100 kb) but extends much further. Sex-specific expression change is also genomically clustered. As genes increasing their expression in humans tend to avoid nuclear lamina domains and be enriched for the gene activator 5-hydroxymethylcytosine, we conclude that, most probably owing to chromatin level control of gene expression, a change in gene expression of one gene likely affects the expression evolution of neighbors, what we term expression piggybacking, an analog of hitchhiking.

  3. Gene expression profiling of di-n-butyl phthalate in normal human mammary epithelial cells.

    PubMed

    Gwinn, Maureen R; Whipkey, Diana L; Tennant, Lora B; Weston, Ainsley

    2007-01-01

    Studies show that female workers in the personal-care industry have an increased risk of developing cancer believed to be the result of increased exposure to toxic and/or carcinogenic chemicals found in cosmetics, hair dyes, and nail polish. One chemical found in multiple personal-care products, di-n-butyl phthalate (DBP), is a known endocrine disruptor and has been found in increased levels in women of childbearing age. The goal of this study was to elucidate mechanisms of phthalate toxicity in normal human cells to provide information concerning interindividual variation and gene-environment interactions. Normal human mammary epithelial cell strains were obtained from discarded tissues following reduction mammoplasty [Cooperative Human Tissue Network (sponsors: NCI/NDRI)]. Gene transcription in each cell strain was analyzed using high-density oligonucleotide DNA microarrays (U133A, Affymetrix) and changes in the expression of selected genes were verified by real-time polymerase chain reaction (PCR) (ABI). DNA microarrays were hybridized with total RNA that was collected after DBP treatment for 5 hr and 10 hr. RNA was harvested from the vehicle control (acetone) at 10 hr. Data Mining Tool software (Affymetrix) was used to separate genes in clusters based on their expression patterns over time. Only 57 genes were found to be altered in all four cell strains following exposure to DBP. These included genes involved in fertility (inhibin, placental growth factor), immune response (tumor necrosis factor induced protein), and antioxidant status (glutathione peroxidase). Data from this study will help clarify the role of DBP in reproductive toxicity, and yield biomarkers of exposure for future epidemiology studies. PMID:17725530

  4. Gene expression profiling of di-n-butyl phthalate in normal human mammary epithelial cells.

    PubMed

    Gwinn, Maureen R; Whipkey, Diana L; Tennant, Lora B; Weston, Ainsley

    2007-01-01

    Studies show that female workers in the personal-care industry have an increased risk of developing cancer believed to be the result of increased exposure to toxic and/or carcinogenic chemicals found in cosmetics, hair dyes, and nail polish. One chemical found in multiple personal-care products, di-n-butyl phthalate (DBP), is a known endocrine disruptor and has been found in increased levels in women of childbearing age. The goal of this study was to elucidate mechanisms of phthalate toxicity in normal human cells to provide information concerning interindividual variation and gene-environment interactions. Normal human mammary epithelial cell strains were obtained from discarded tissues following reduction mammoplasty [Cooperative Human Tissue Network (sponsors: NCI/NDRI)]. Gene transcription in each cell strain was analyzed using high-density oligonucleotide DNA microarrays (U133A, Affymetrix) and changes in the expression of selected genes were verified by real-time polymerase chain reaction (PCR) (ABI). DNA microarrays were hybridized with total RNA that was collected after DBP treatment for 5 hr and 10 hr. RNA was harvested from the vehicle control (acetone) at 10 hr. Data Mining Tool software (Affymetrix) was used to separate genes in clusters based on their expression patterns over time. Only 57 genes were found to be altered in all four cell strains following exposure to DBP. These included genes involved in fertility (inhibin, placental growth factor), immune response (tumor necrosis factor induced protein), and antioxidant status (glutathione peroxidase). Data from this study will help clarify the role of DBP in reproductive toxicity, and yield biomarkers of exposure for future epidemiology studies.

  5. Fully Bayesian mixture model for differential gene expression: simulations and model checks.

    PubMed

    Lewin, Alex; Bochkina, Natalia; Richardson, Sylvia

    2007-01-01

    We present a Bayesian hierarchical model for detecting differentially expressed genes using a mixture prior on the parameters representing differential effects. We formulate an easily interpretable 3-component mixture to classify genes as over-expressed, under-expressed and non-differentially expressed, and model gene variances as exchangeable to allow for variability between genes. We show how the proportion of differentially expressed genes, and the mixture parameters, can be estimated in a fully Bayesian way, extending previous approaches where this proportion was fixed and empirically estimated. Good estimates of the false discovery rates are also obtained. Different parametric families for the mixture components can lead to quite different classifications of genes for a given data set. Using Affymetrix data from a knock out and wildtype mice experiment, we show how predictive model checks can be used to guide the choice between possible mixture priors. These checks show that extending the mixture model to allow extra variability around zero instead of the usual point mass null fits the data better. A software package for R is available.

  6. Study on the antiendotoxin action of Pulsatillae Decoction using an Affymetrix rat genome array.

    PubMed

    Hu, Yiyi; Chen, Xi; Lin, Hong; Hu, Yuanliang; Mu, Xiang

    2009-01-01

    A high-throughput and efficient Affymetrix rat genome array was used to investigate the pharmacological mechanism of the traditional Chinese medicine, Pulsatillae Decoction (PD), used for the treatment of diseases induced by lipopolysaccharide (LPS). Rat intestinal microvascular endothelial cells (RIMECs) were challenged with 1mug/ml LPS for 3h, and then treated with PD at a concentration of 1mg/ml for 24h. Total RNA from each treatment group was extracted from cultured RIMECs for detection by the Affymetrix Rat Genome 230 2.0 Array. The results showed that 36 genes were upregulated and 33 genes were downregulated in the LPS group vs. the blank control group; 566 genes were upregulated and 12 genes were downregulated in the PD-treated group vs. the LPS group; and 93 genes were upregulated and 29 genes were downregulated in the PD-treated group vs. the blank control group. The analysis of these data suggested that PD specifically and effectively reduce damage induced by LPS, and improved physiological and biochemical responses to counteract the effects of LPS.

  7. Neighboring Genes Show Correlated Evolution in Gene Expression

    PubMed Central

    Ghanbarian, Avazeh T.; Hurst, Laurence D.

    2015-01-01

    When considering the evolution of a gene’s expression profile, we commonly assume that this is unaffected by its genomic neighborhood. This is, however, in contrast to what we know about the lack of autonomy between neighboring genes in gene expression profiles in extant taxa. Indeed, in all eukaryotic genomes genes of similar expression-profile tend to cluster, reflecting chromatin level dynamics. Does it follow that if a gene increases expression in a particular lineage then the genomic neighbors will also increase in their expression or is gene expression evolution autonomous? To address this here we consider evolution of human gene expression since the human-chimp common ancestor, allowing for both variation in estimation of current expression level and error in Bayesian estimation of the ancestral state. We find that in all tissues and both sexes, the change in gene expression of a focal gene on average predicts the change in gene expression of neighbors. The effect is highly pronounced in the immediate vicinity (<100 kb) but extends much further. Sex-specific expression change is also genomically clustered. As genes increasing their expression in humans tend to avoid nuclear lamina domains and be enriched for the gene activator 5-hydroxymethylcytosine, we conclude that, most probably owing to chromatin level control of gene expression, a change in gene expression of one gene likely affects the expression evolution of neighbors, what we term expression piggybacking, an analog of hitchhiking. PMID:25743543

  8. Differential gene expression in mouse liver associated with the hepatoprotective effect of clofibrate

    SciTech Connect

    Moffit, Jeffrey S.; Koza-Taylor, Petra H.; Holland, Ricky D.; Thibodeau, Michael S.; Beger, Richard D.; Lawton, Michael P.; Manautou, Jose E. . E-mail: jose.manautou@uconn.edu

    2007-07-15

    Pretreatment of mice with the peroxisome proliferator clofibrate (CFB) protects against acetaminophen (APAP)-induced hepatotoxicity. Previous studies have shown that activation of the nuclear peroxisome proliferator activated receptor-alpha (PPAR{alpha}) is required for this effect. The present study utilizes gene expression profile analysis to identify potential pathways contributing to PPAR{alpha}-mediated hepatoprotection. Gene expression profiles were compared between wild type and PPAR{alpha}-null mice pretreated with vehicle or CFB (500 mg/kg, i.p., daily for 10 days) and then challenged with APAP (400 mg/kg, p.o.). Total hepatic RNA was isolated 4 h after APAP treatment and hybridized to Affymetrix Mouse Genome MGU74 v2.0 GeneChips. Gene expression analysis was performed utilizing GeneSpring (registered) software. Our analysis identified 53 genes of interest including vanin-1, cell cycle regulators, lipid-metabolizing enzymes, and aldehyde dehydrogenase 2, an acetaminophen binding protein. Vanin-1 could be important for CFB-mediated hepatoprotection because this protein is involved in the synthesis of cysteamine and cystamine. These are potent antioxidants capable of ameliorating APAP toxicity in rodents and humans. HPLC-ESI/MS/MS analysis of liver extracts indicates that enhanced vanin-1 gene expression results in elevated cystamine levels, which could be mechanistically associated with CFB-mediated hepatoprotection.

  9. Distinctive gene expression signatures in rheumatoid arthritis synovial tissue fibroblast cells: correlates with disease activity.

    PubMed

    Galligan, C L; Baig, E; Bykerk, V; Keystone, E C; Fish, E N

    2007-09-01

    Gene expression profiling of rheumatoid arthritis (RA) and osteoarthritis (OA) joint tissue samples provides a unique insight into the gene signatures involved in disease development and progression. Fibroblast-like synovial (FLS) cells were obtained from RA, OA and control trauma joint tissues (non-RA, non-OA) and RNA was analyzed by Affymetrix microarray. Thirty-four genes specific to RA and OA FLS cells were identified (P<0.05). HOXD10, HOXD11, HOXD13, CCL8 and LIM homeobox 2 were highly and exclusively expressed in RA and CLU, sarcoglycan-gamma, GPR64, POU3F3, peroxisome proliferative activated receptor-gamma and tripartite motif-containing 2 were expressed only in OA. The data also revealed expression heterogeneity for patients with the same disease. To address disease heterogeneity in RA FLS cells, we examined the effects of clinical disease parameters (Health Assessment Questionnaire (HAQ) score, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF)) and drug therapies (methotrexate/prednisone) on RA FLS cell gene expression. Eight specific and unique correlations were identified: human leukocyte antigen (HLA)-DQA2 with HAQ score; Clec12A with RF; MAB21L2, SIAT7E, HAPLN1 and BAIAP2L1 with CRP level; RGMB and OSAP with ESR. Signature RA FLS cell gene expression profiles may provide insights into disease pathogenesis and have utility in diagnosis, prognosis and drug responsiveness. PMID:17568789

  10. Developmental and Environmental Regulation of Aquaporin Gene Expression across Populus Species: Divergence or Redundancy?

    PubMed Central

    Cohen, David; Bogeat-Triboulot, Marie-Béatrice; Vialet-Chabrand, Silvère; Merret, Rémy; Courty, Pierre-Emmanuel; Moretti, Sébastien; Bizet, François; Guilliot, Agnès; Hummel, Irène

    2013-01-01

    Aquaporins (AQPs) are membrane channels belonging to the major intrinsic proteins family and are known for their ability to facilitate water movement. While in Populus trichocarpa, AQP proteins form a large family encompassing fifty-five genes, most of the experimental work focused on a few genes or subfamilies. The current work was undertaken to develop a comprehensive picture of the whole AQP gene family in Populus species by delineating gene expression domain and distinguishing responsiveness to developmental and environmental cues. Since duplication events amplified the poplar AQP family, we addressed the question of expression redundancy between gene duplicates. On these purposes, we carried a meta-analysis of all publicly available Affymetrix experiments. Our in-silico strategy controlled for previously identified biases in cross-species transcriptomics, a necessary step for any comparative transcriptomics based on multispecies design chips. Three poplar AQPs were not supported by any expression data, even in a large collection of situations (abiotic and biotic constraints, temporal oscillations and mutants). The expression of 11 AQPs was never or poorly regulated whatever the wideness of their expression domain and their expression level. Our work highlighted that PtTIP1;4 was the most responsive gene of the AQP family. A high functional divergence between gene duplicates was detected across species and in response to tested cues, except for the root-expressed PtTIP2;3/PtTIP2;4 pair exhibiting 80% convergent responses. Our meta-analysis assessed key features of aquaporin expression which had remained hidden in single experiments, such as expression wideness, response specificity and genotype and environment interactions. By consolidating expression profiles using independent experimental series, we showed that the large expansion of AQP family in poplar was accompanied with a strong divergence of gene expression, even if some cases of functional redundancy

  11. Whole Blood Gene Expression and Atrial Fibrillation: The Framingham Heart Study

    PubMed Central

    Lin, Honghuang; Yin, Xiaoyan; Lunetta, Kathryn L.; Dupuis, Josée; McManus, David D.; Lubitz, Steven A.; Magnani, Jared W.; Joehanes, Roby; Munson, Peter J.; Larson, Martin G.; Levy, Daniel; Ellinor, Patrick T.; Benjamin, Emelia J.

    2014-01-01

    Background Atrial fibrillation (AF) involves substantial electrophysiological, structural and contractile remodeling. We hypothesize that characterizing gene expression might uncover important pathways related to AF. Methods and Results We performed genome-wide whole blood transcriptomic profiling (Affymetrix Human Exon 1.0 ST Array) of 2446 participants (mean age 66±9 years, 55% women) from the Offspring cohort of Framingham Heart Study. The study included 177 participants with prevalent AF, 143 with incident AF during up to 7 years follow up, and 2126 participants with no AF. We identified seven genes statistically significantly up-regulated with prevalent AF. The most significant gene, PBX1 (P = 2.8×10−7), plays an important role in cardiovascular development. We integrated differential gene expression with gene-gene interaction information to identify several signaling pathways possibly involved in AF-related transcriptional regulation. We did not detect any statistically significant transcriptomic associations with incident AF. Conclusion We examined associations of gene expression with AF in a large community-based cohort. Our study revealed several genes and signaling pathways that are potentially involved in AF-related transcriptional regulation. PMID:24805109

  12. Vascular gene expression: a hypothesis

    PubMed Central

    Martínez-Navarro, Angélica C.; Galván-Gordillo, Santiago V.; Xoconostle-Cázares, Beatriz; Ruiz-Medrano, Roberto

    2013-01-01

    The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a “primitive” vascular tissue (a lycophyte), as well as from others that lack a true vascular tissue (a bryophyte), and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non-vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT, and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants. PMID:23882276

  13. Systematic analysis of a novel human renal glomerulus-enriched gene expression dataset.

    PubMed

    Lindenmeyer, Maja T; Eichinger, Felix; Sen, Kontheari; Anders, Hans-Joachim; Edenhofer, Ilka; Mattinzoli, Deborah; Kretzler, Matthias; Rastaldi, Maria P; Cohen, Clemens D

    2010-01-01

    Glomerular diseases account for the majority of cases with chronic renal failure. Several genes have been identified with key relevance for glomerular function. Quite a few of these genes show a specific or preferential mRNA expression in the renal glomerulus. To identify additional candidate genes involved in glomerular function in humans we generated a human renal glomerulus-enriched gene expression dataset (REGGED) by comparing gene expression profiles from human glomeruli and tubulointerstitium obtained from six transplant living donors using Affymetrix HG-U133A arrays. This analysis resulted in 677 genes with prominent overrepresentation in the glomerulus. Genes with 'a priori' known prominent glomerular expression served for validation and were all found in the novel dataset (e.g. CDKN1, DAG1, DDN, EHD3, MYH9, NES, NPHS1, NPHS2, PDPN, PLA2R1, PLCE1, PODXL, PTPRO, SYNPO, TCF21, TJP1, WT1). The mRNA expression of several novel glomerulus-enriched genes in REGGED was validated by qRT-PCR. Gene ontology and pathway analysis identified biological processes previously not reported to be of relevance in glomeruli of healthy human adult kidneys including among others axon guidance. This finding was further validated by assessing the expression of the axon guidance molecules neuritin (NRN1) and roundabout receptor ROBO1 and -2. In diabetic nephropathy, a prevalent glomerulopathy, differential regulation of glomerular ROBO2 mRNA was found.In summary, novel transcripts with predominant expression in the human glomerulus could be identified using a comparative strategy on microdissected nephrons. A systematic analysis of this glomerulus-specific gene expression dataset allows the detection of target molecules and biological processes involved in glomerular biology and renal disease. PMID:20634963

  14. Simultaneous gene expression signature of heart and peripheral blood mononuclear cells in astemizole-treated rats.

    PubMed

    Lee, Eun-Hee; Oh, Jung-Hwa; Park, Han-Jin; Kim, Do-Geun; Lee, Jong-Hwa; Kim, Choong-Yong; Kwon, Myung-Sang; Yoon, Seokjoo

    2010-08-01

    We investigated the effects of astemizole, a second-generation antihistamine, on the heart and peripheral blood mononuclear cells (PBMCs) and identified the early markers of its cardiotoxicity using gene expression profiling. Astemizole causes torsades de pointes, which is a type of ventricular tachycardia. We administered astemizole (dosage: 20, 60 mg/kg) to male Sprague-Dawley rats, using an oral gavage. Cardiac tissue and PBMCs were collected from the rats 4 h after treatment. Gene expression profiles were obtained using an Affymetrix GeneChip. The most deregulated genes were associated with energy metabolism pathways and calcium ion homeostasis in the heart of astemizole-treated rats. The most altered genes in the PBMCs were those involved in developmental processes and cardiotoxicity. Genes related to the response to oxidative stress, reactive oxygen species, heat shock proteins, hypoxia, immunity, and inflammation were also deregulated in the heart and PBMCs. These data provide further insight into the genetic pathways affected by astemizole. In addition, the simultaneously deregulated genes identified herein may be further studied. It will be interesting to find out whether single genes or certain sets of these genes could finally serve as biomarkers for cardiotoxicity of astemizole or other similar antihistamine drugs. PMID:20221588

  15. Hepatic temporal gene expression profiling in Helicobacter hepaticus-infected A/JCr mice.

    PubMed

    Boutin, Samuel R; Rogers, Arlin B; Shen, Zeli; Fry, Rebecca C; Love, Jennifer A; Nambiar, Prashant R; Suerbaum, Sebastian; Fox, James G

    2004-01-01

    Helicobacter hepaticus infection of A/JCr mice is a model of infectious liver cancer. We monitored hepatic global gene expression profiles in H. hepaticus infected and control male A/JCr mice at 3 months, 6 months, and 1 year of age using an Affymetrix-based oligonucleotide microarray platform on the premise that a specific genetic expression signature at isolated time points would be indicative of disease status. Model based expression index comparisons generated by dChip yielded consistent profiles of differential gene expression for H. hepaticus infected male mice with progressive liver disease versus uninfected control mice within each age group. Linear discriminant analysis and principal component analysis allowed segregation of mice based on combined age and lesion status, or age alone. Up-regulation of putative tumor markers correlated with advancing hepatocellular dysplasia. Transcriptionally down-regulated genes in mice with liver lesions included those related to peroxisome proliferator, fatty acid, and steroid metabolism pathways. In conclusion, transcriptional profiling of hepatic genes documented gene expression signatures in the livers of H. hepaticus infected male A/JCr mice with chronic progressive hepatitis and preneoplastic liver lesions, complemented the histopathological diagnosis, and suggested molecular targets for the monitoring and intervention of disease progression prior to the onset of hepatocellular neoplasia.

  16. Duplicate genes increase gene expression diversity within and between species.

    PubMed

    Gu, Zhenglong; Rifkin, Scott A; White, Kevin P; Li, Wen-Hsiung

    2004-06-01

    Using microarray gene expression data from several Drosophila species and strains, we show that duplicated genes, compared with single-copy genes, significantly increase gene expression diversity during development. We show further that duplicate genes tend to cause expression divergences between Drosophila species (or strains) to evolve faster than do single-copy genes. This conclusion is also supported by data from different yeast strains.

  17. Systems Biophysics of Gene Expression

    PubMed Central

    Vilar, Jose M.G.; Saiz, Leonor

    2013-01-01

    Gene expression is a process central to any form of life. It involves multiple temporal and functional scales that extend from specific protein-DNA interactions to the coordinated regulation of multiple genes in response to intracellular and extracellular changes. This diversity in scales poses fundamental challenges to the use of traditional approaches to fully understand even the simplest gene expression systems. Recent advances in computational systems biophysics have provided promising avenues to reliably integrate the molecular detail of biophysical process into the system behavior. Here, we review recent advances in the description of gene regulation as a system of biophysical processes that extend from specific protein-DNA interactions to the combinatorial assembly of nucleoprotein complexes. There is now basic mechanistic understanding on how promoters controlled by multiple, local and distal, DNA binding sites for transcription factors can actively control transcriptional noise, cell-to-cell variability, and other properties of gene regulation, including precision and flexibility of the transcriptional responses. PMID:23790365

  18. Neuronatin: A New Inflammation Gene Expressed on the Aortic Endothelium of Diabetic Mice

    PubMed Central

    Mzhavia, Nino; Yu, Shuiqing; Ikeda, Shota; Chu, Tehua T.; Goldberg, Ira; Dansky, Hayes M.

    2008-01-01

    OBJECTIVE—Identification of arterial genes and pathways altered in obesity and diabetes. RESEARCH DESIGN AND METHODS—Aortic gene expression profiles of obese and diabetic db/db, high-fat diet–fed C57BL/6J, and control mice were obtained using mouse Affymetrix arrays. Neuronatin (Nnat) was selected for further analysis. To determine the function of Nnat, a recombinant adenovirus (Ad-Nnat) was used to overexpress the Nnat gene in primary endothelial cells and in the mouse aorta in vivo. RESULTS—Nnat, a gene of unknown vascular function, was upregulated in the aortas of db/db and high-fat diet–fed mice. Nnat gene expression was increased in db/db mouse aorta endothelial cells. Nnat protein was localized to aortic endothelium and was selectively increased in the endothelium of db/db mice. Infection of primary human aortic endothelial cells (HAECs) with Ad-Nnat increased expression of a panel of nuclear factor-κB (NF-κB)-regulated genes, including inflammatory cytokines, chemokines, and cell adhesion molecules. Infection of mouse carotid arteries in vivo with the Ad-Nnat increased expression of vascular cell adhesion molecule 1 protein. Nnat activation of NF-κB and inflammatory gene expression in HAECs was mediated through pathways distinct from tumor necrosis factor-α. Nnat expression stimulated p38, Jun NH2-terminal kinase, extracellular signal–related kinase, and AKT kinase phosphorylation. Phosphatidylinositol 3-kinase and p38 inhibitors prevented Nnat-mediated activation of NF-κB–induced gene expression. CONCLUSIONS—Nnat expression is increased in endothelial cells of obese and diabetic mouse blood vessels. The effects of Nnat on inflammatory pathways in vitro and in vivo suggest a pathophysiological role of this new gene in diabetic vascular diseases. PMID:18591389

  19. Influence of sex on gene expression in human corneal epithelial cells

    PubMed Central

    Suzuki, Tomo; Richards, Stephen M.; Liu, Shaohui; Jensen, Roderick V.

    2009-01-01

    Purpose Sex-associated differences have been identified in the anatomy, physiology and pathophysiology of the human cornea. We hypothesize that many of these differences are due to fundamental variations in gene expression. Our objective in this study was to determine whether such differences exist in human corneal epithelial cells both in vivo and in vitro. Methods Human corneal epithelial cells were isolated from the corneoscleral rims of male and female donors. Cells were processed either directly for RNA extraction, or first cultured in phenol red-free keratinocyte serum-free media. The RNA samples were examined for differentially expressed mRNAs by using of CodeLink Bioarrays and Affymetrix GeneChips. Data were analyzed with GeneSifter.Net software. Results Our results demonstrate that sex significantly influences the expression of over 600 genes in human corneal epithelial cells in vivo. These genes are involved in a broad spectrum of biologic processes, molecular functions and cellular components, such as metabolic processes, DNA replication, cell migration, RNA binding, oxidoreductase activity and nucleoli. We also identified significant, sex-related effects on gene expression in human corneal epithelial cells in vitro. However, with few exceptions (e.g., X- and Y-linked genes), these sex-related differences in gene expression in vitro were typically different than those in vivo. Conclusions Our findings support our hypothesis that sex-related differences exist in the gene expression of human corneal epithelial cells. Variations in gene expression may contribute to sex-related differences in the prevalence of certain corneal diseases. PMID:20011627

  20. TIBS: a web database to browse gene expression in irritable bowel syndrome.

    PubMed

    Yan, Jing; Xu, Yan; Hu, Brian; Alnajm, Sammy; Liu, Lina; Lu, Yin; Sun, Zhiguang; Cheng, Feng

    2014-08-01

    Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder. Its symptoms include chronic abdominal pain, bloating gas, diarrhea and constipation. Many IBS patients also have psychological symptoms like depression or anxiety. These unpleasant symptoms significantly lower patients׳ quality of life. The prevalence of IBS in Europe and North America is about 10-15% of the population, which makes IBS a disorder with a high social cost. The pathophysiology of IBS is considered to be multifactorial and the exact cause of the disease remains poorly understood. Recently, a genome-wide expression microarray technique has been applied to investigate the possible mechanisms of IBS. However, a user-friendly database that allows scientists without bioinformatics background to query gene expression levels in these data sets and compare gene expression patterns across different tissues has not yet been established. Therefore, we have integrated four public expression microarray data (320 samples) from the Gene Expression Omnibus (GEO) and ArrayExpress databases into an online database called Transcriptome of Irritable Bowel Syndrome (TIBS). The gene expression change in IBS patients compared to healthy volunteers or UC patients in jejunum, sigmoid colon, rectum, and descending colon can be queried by gene symbols. Users can compare gene expression levels of IBS patients across these tissues. Sex difference of gene expression in IBS patients was also shown in the database. The current version of TIBS database contains 42,400 annotated gene probe sets represented on the Affymetrix Human Genome U133 plus 2.0 platform. TIBS will be an invaluable resource for a better understanding of the pathogenesis of IBS at the molecular level and for drug development. The TIBS database is available online at http://www.chengfeng.info/tibs_database.html.

  1. miRNAs in multiple myeloma – a survival relevant complex regulator of gene expression

    PubMed Central

    Seckinger, Anja; MeiΔner, Tobias; Moreaux, Jérôme; Benes, Vladimir; Hillengass, Jens; Castoldi, Mirco; Zimmermann, Jürgen; Ho, Anthony D.; Jauch, Anna; Goldschmidt, Hartmut; Klein, Bernard; Hose, Dirk

    2015-01-01

    Purpose microRNAs regulate gene-expression in biological and pathophysiological processes, including multiple myeloma. Here we address i) What are the number and magnitude of changes in miRNA-expression between normal plasma cells and myeloma- or MGUS-samples, and the latter two? ii) What is the biological relevance and how does miRNA-expression impact on gene-expression? iii) Is there a prognostic significance, and what is its background? Experimental design Ninety-two purified myeloma-, MGUS-, normal plasma cell- and myeloma cell line-samples were investigated using miChip-arrays interrogating 559 human miRNAs. Impact on gene-expression was assessed by Affymetrix DNA-microarrays in two cohorts of myeloma patients (n = 677); chromosomal aberrations were assessed by iFISH, survival for 592 patients undergoing up-front high-dose chemotherapy. Results Compared to normal plasma cells, 67/559 miRNAs (12%) with fold changes of 4.6 to −3.1 are differentially expressed in myeloma-, 20 (3.6%) in MGUS-samples, and three (0.5%) between MGUS and myeloma. Expression of miRNAs is associated with proliferation, chromosomal aberrations, tumor mass, and gene expression-based risk-scores. This holds true for target-gene signatures of regulated mRNAs. miRNA-expression confers prognostic significance for event-free and overall survival, as do respective target-gene signatures. Conclusions The myeloma-miRNome confers a pattern of small changes of individual miRNAs impacting on gene-expression, biological functions, and survival. PMID:26472281

  2. The Gene Expression Omnibus database

    PubMed Central

    Clough, Emily; Barrett, Tanya

    2016-01-01

    The Gene Expression Omnibus (GEO) database is an international public repository that archives and freely distributes high-throughput gene expression and other functional genomics data sets. Created in 2000 as a worldwide resource for gene expression studies, GEO has evolved with rapidly changing technologies and now accepts high-throughput data for many other data applications, including those that examine genome methylation, chromatin structure, and genome–protein interactions. GEO supports community-derived reporting standards that specify provision of several critical study elements including raw data, processed data, and descriptive metadata. The database not only provides access to data for tens of thousands of studies, but also offers various Web-based tools and strategies that enable users to locate data relevant to their specific interests, as well as to visualize and analyze the data. This chapter includes detailed descriptions of methods to query and download GEO data and use the analysis and visualization tools. The GEO homepage is at http://www.ncbi.nlm.nih.gov/geo/. PMID:27008011

  3. The Gene Expression Omnibus Database.

    PubMed

    Clough, Emily; Barrett, Tanya

    2016-01-01

    The Gene Expression Omnibus (GEO) database is an international public repository that archives and freely distributes high-throughput gene expression and other functional genomics data sets. Created in 2000 as a worldwide resource for gene expression studies, GEO has evolved with rapidly changing technologies and now accepts high-throughput data for many other data applications, including those that examine genome methylation, chromatin structure, and genome-protein interactions. GEO supports community-derived reporting standards that specify provision of several critical study elements including raw data, processed data, and descriptive metadata. The database not only provides access to data for tens of thousands of studies, but also offers various Web-based tools and strategies that enable users to locate data relevant to their specific interests, as well as to visualize and analyze the data. This chapter includes detailed descriptions of methods to query and download GEO data and use the analysis and visualization tools. The GEO homepage is at http://www.ncbi.nlm.nih.gov/geo/. PMID:27008011

  4. Gene Expression Studies in Mosquitoes

    PubMed Central

    Chen, Xlao-Guang; Mathur, Geetika; James, Anthony A.

    2009-01-01

    Research on gene expression in mosquitoes is motivated by both basic and applied interests. Studies of genes involved in hematophagy, reproduction, olfaction, and immune responses reveal an exquisite confluence of biological adaptations that result in these highly-successful life forms. The requirement of female mosquitoes for a bloodmeal for propagation has been exploited by a wide diversity of viral, protozoan and metazoan pathogens as part of their life cycles. Identifying genes involved in host-seeking, blood feeding and digestion, reproduction, insecticide resistance and susceptibility/refractoriness to pathogen development is expected to provide the bases for the development of novel methods to control mosquito-borne diseases. Advances in mosquito transgenesis technologies, the availability of whole genome sequence information, mass sequencing and analyses of transcriptomes and RNAi techniques will assist development of these tools as well as deepen the understanding of the underlying genetic components for biological phenomena characteristic of these insect species. PMID:19161831

  5. Stress, and pathogen response gene expression in modeled microgravity

    NASA Technical Reports Server (NTRS)

    Sundaresan, Alamelu; Pellis, Neal R.

    2006-01-01

    Purpose: Immune suppression in microgravity has been well documented. With the advent of human exploration and long-term space travel, the immune system of the astronaut must be optimally maintained. It is important to investigate the expression patterns of cytokine genes, because they are directly related to immune response. Heat shock proteins (HSPs), also called stress proteins, are a group of proteins that are present in the cells of every life form. These proteins are induced when a cell responds to stressors such as heat, cold and oxygen deprivation. Microgravity is another stressor that may regulate HSPs. Heat shock proteins trigger immune response through activities that occur both inside the cell (intracellular) and outside the cell (extracellular). Knowledge about these two gene groups could lead to establishment of a blueprint of the immune response and adaptation-related genes in the microgravity environment. Methods: Human peripheral blood cells were cultured in 1g (T flask) and modeled microgravity (MMG, rotating-wall vessel) for 24 and 72 hours. Cell samples were collected and subjected to gene array analysis using the Affymetrix HG_U95 array. Data was collected and subjected to a two-way analysis of variance. The genes related to immune and stress responses were analyzed. Results and Conclusions: HSP70 was up-regulated by more than two fold in microgravity culture, while HSP90 was significantly down-regulated. HSP70 is not typically expressed in all kinds of cells, but it is expressed at high levels in stress conditions. HSP70 participates in translation, protein translocation, proteolysis and protein folding, suppressing aggregation and reactivating denatured proteins. Increased serum HSP70 levels correlate with a better outcome for heat-stroke or severe trauma patients. At the same time, elevated serum levels of HSP70 have been detected in patients with peripheral or renal vascular disease. HSP90 has been identified in the cytosol, nucleus and

  6. Gene expression profiles of prostate cancer reveal involvement of multiple molecular pathways in the metastatic process

    PubMed Central

    Chandran, Uma R; Ma, Changqing; Dhir, Rajiv; Bisceglia, Michelle; Lyons-Weiler, Maureen; Liang, Wenjing; Michalopoulos, George; Becich, Michael; Monzon, Federico A

    2007-01-01

    Background Prostate cancer is characterized by heterogeneity in the clinical course that often does not correlate with morphologic features of the tumor. Metastasis reflects the most adverse outcome of prostate cancer, and to date there are no reliable morphologic features or serum biomarkers that can reliably predict which patients are at higher risk of developing metastatic disease. Understanding the differences in the biology of metastatic and organ confined primary tumors is essential for developing new prognostic markers and therapeutic targets. Methods Using Affymetrix oligonucleotide arrays, we analyzed gene expression profiles of 24 androgen-ablation resistant metastatic samples obtained from 4 patients and a previously published dataset of 64 primary prostate tumor samples. Differential gene expression was analyzed after removing potentially uninformative stromal genes, addressing the differences in cellular content between primary and metastatic tumors. Results The metastatic samples are highly heterogenous in expression; however, differential expression analysis shows that 415 genes are upregulated and 364 genes are downregulated at least 2 fold in every patient with metastasis. The expression profile of metastatic samples reveals changes in expression of a unique set of genes representing both the androgen ablation related pathways and other metastasis related gene networks such as cell adhesion, bone remodelling and cell cycle. The differentially expressed genes include metabolic enzymes, transcription factors such as Forkhead Box M1 (FoxM1) and cell adhesion molecules such as Osteopontin (SPP1). Conclusion We hypothesize that these genes have a role in the biology of metastatic disease and that they represent potential therapeutic targets for prostate cancer. PMID:17430594

  7. Unbalanced placental expression of imprinted genes in human intrauterine growth restriction.

    PubMed

    McMinn, J; Wei, M; Schupf, N; Cusmai, J; Johnson, E B; Smith, A C; Weksberg, R; Thaker, H M; Tycko, B

    2006-01-01

    Imprinted genes control fetal and placental growth in mice and in rare human syndromes, but the role of these genes in sporadic intrauterine growth restriction (IUGR) is less well-studied. We measured the ratio of mRNA from a maternally expressed imprinted gene, PHLDA2, to that from a paternally expressed imprinted gene, MEST, by Northern blotting in 38 IUGR-associated placentae and 75 non-IUGR placentae and found an increase in the PHLDA2/MEST mRNA ratio in IUGR (p=0.0001). Altered expression of PHLDA2 and MEST was not accompanied by changes in DNA methylation within their imprinting centers, and immunohistochemistry showed PHLDA2 protein appropriately restricted to villous and intermediate cytotrophoblast in the IUGR placentae. We next did a genome-wide survey of mRNA expression in 14 IUGR placentae with maternal vascular under-perfusion compared to 15 non-IUGR placentae using Affymetrix U133A microarrays. In this series six imprinted genes were differentially expressed by ANOVA with a Benjamini-Hochberg false discovery rate of 0.05, with increased expression of PHLDA2 and decreased expression of MEST, MEG3, GATM, GNAS and PLAGL1 in IUGR placentae. At lower significance, we found IGF2 mRNA decreased and CDKN1C mRNA increased in the IUGR cases. We confirmed the significant reduction in MEG3 non-translated RNA in IUGR placentae by Northern blotting. In addition to imprinted genes, the microarray data highlighted non-imprinted genes acting in endocrine signaling (LEP, CRH, HPGD, INHBA), tissue growth (IGF1), immune modulation (INDO, PSG-family genes), oxidative metabolism (GLRX), vascular function (AGTR1, DSCR1) and metabolite transport (SLC-family solute carriers) as differentially expressed in IUGR vs. non-IUGR placentae. PMID:16125225

  8. Feasibility of Using Gene Expression Analysis to Study Canine Soft Tissue Sarcomas

    PubMed Central

    Mahoney, Jennifer A.; Fisher, Julie C.; Snyder, Stacey A.; Hauck, Marlene L.

    2013-01-01

    The prognosis given for canine soft tissue sarcomas (STSs) is based primarily on histopathologic grade. The decision to administer adjuvant chemotherapy is difficult, since less than half of patients with high-grade STSs develop metastatic disease. We hypothesize that there is a gene signature which will improve our ability to predict development of metastatic disease in STS patients. The objective of this study was to determine the feasibility of using cDNA microarray and quantitative real-time PCR (qRT-PCR) analysis to determine gene expression patterns in metastatic versus non-metastatic canine STSs, given the inherent heterogeneity of this group of tumors. Five STSs from dogs with metastatic disease were evaluated in comparison to eight STSs from dogs without metastasis. Tumor RNA was extracted, processed and labeled for application to the Affymetrix Canine Genechip 2.0 Array. Array fluorescence was normalized using D-Chip software and data analysis was performed with JMP/Genomics. Differential gene expression was validated using qRT-PCR. Over 200 genes were differentially expressed at a false discovery rate of 5%. Differential gene expression was validated for five genes upregulated in metastatic tumors. Quantitative RT-PCR confirmed increased relative expression of all five genes of interest in the metastatic STSs. Our results demonstrate that microarray and qRT-PCR are feasible methods for comparing gene signatures in canine STSs. Further evaluation of differences in gene expression between metastatic and non-metastatic STSs is likely to identify genes important in the development of metastatic disease and improve our ability to prognosticate for individual patients. PMID:21076837

  9. Identification of genes preferentially expressed by microglia and upregulated during cuprizone-induced inflammation.

    PubMed

    Bédard, Andréanne; Tremblay, Pierrot; Chernomoretz, Ariel; Vallières, Luc

    2007-06-01

    Microglia, monocytes, and peripheral macrophages share a common origin and many characteristics, but what distinguishes them from each other at the level of gene expression remains largely unknown. In this study, we compared the transcriptional profiles of freshly purified microglia, monocytes, and spleen macrophages using Affymetrix Mouse Genome arrays to identify genes predominantly expressed by microglia. Among tens of thousands of genes assayed, 127 potential candidates were found, including nine newly discovered genes encoding plasma membrane and extracellular proteins. In the brain, the latter were selectively expressed by microglia, as revealed by in situ hybridization. Three of them were confirmed to be exclusively (MSR2) or predominantly (GPR12, GPR34) expressed in the brain compared to the other tissues examined. Furthermore, all of these genes were upregulated in activated microglia after treatment with the demyelinating toxin cuprizone, suggesting that they play roles in neuroinflammation. In conclusion, this study reports the identification of new selective markers for microglia, which should prove useful not only to identify and isolate these cells, but also to better understand their distinctive properties. PMID:17285589

  10. Gene expression signature in organized and growth arrested mammaryacini predicts good outcome in breast cancer

    SciTech Connect

    Fournier, Marcia V.; Martin, Katherine J.; Kenny, Paraic A.; Xhaja, Kris; Bosch, Irene; Yaswen, Paul; Bissell, Mina J.

    2006-02-08

    To understand how non-malignant human mammary epithelial cells (HMEC) transit from a disorganized proliferating to an organized growth arrested state, and to relate this process to the changes that occur in breast cancer, we studied gene expression changes in non-malignant HMEC grown in three-dimensional cultures, and in a previously published panel of microarray data for 295 breast cancer samples. We hypothesized that the gene expression pattern of organized and growth arrested mammary acini would share similarities with breast tumors with good prognoses. Using Affymetrix HG-U133A microarrays, we analyzed the expression of 22,283 gene transcripts in two HMEC cell lines, 184 (finite life span) and HMT3522 S1 (immortal non-malignant), on successive days post-seeding in a laminin-rich extracellular matrix assay. Both HMECs underwent growth arrest in G0/G1 and differentiated into polarized acini between days 5 and 7. We identified gene expression changes with the same temporal pattern in both lines. We show that genes that are significantly lower in the organized, growth arrested HMEC than in their proliferating counterparts can be used to classify breast cancer patients into poor and good prognosis groups with high accuracy. This study represents a novel unsupervised approach to identifying breast cancer markers that may be of use clinically.

  11. Brain gene expression differences are associated with abnormal tail biting behavior in pigs.

    PubMed

    Brunberg, E; Jensen, P; Isaksson, A; Keeling, L J

    2013-03-01

    Knowledge about gene expression in animals involved in abnormal behaviors can contribute to the understanding of underlying biological mechanisms. This study aimed to explore the motivational background to tail biting, an abnormal injurious behavior and severe welfare problem in pig production. Affymetrix microarrays were used to investigate gene expression differences in the hypothalamus and prefrontal cortex of pigs performing tail biting, pigs receiving bites to the tail and neutral pigs who were not involved in the behavior. In the hypothalamus, 32 transcripts were differentially expressed (P < 0.05) when tail biters were compared with neutral pigs, 130 when comparing receiver pigs with neutrals, and two when tail biters were compared with receivers. In the prefrontal cortex, seven transcripts were differently expressed in tail biters when compared with neutrals, seven in receivers vs. neutrals and none in the tail biters vs. receivers. In total, 19 genes showed a different expression pattern in neutral pigs when compared with both performers and receivers. This implies that the functions of these may provide knowledge about why the neutral pigs are not involved in tail biting behavior as performers or receivers. Among these 19 transcripts were genes associated with production traits in pigs (PDK4), sociality in humans and mice (GTF2I) and novelty seeking in humans (EGF). These are in line with hypotheses linking tail biting with reduced back fat thickness and explorative behavior. PMID:23146156

  12. Mucosal Gene Expression of Antimicrobial Peptides in Inflammatory Bowel Disease Before and After First Infliximab Treatment

    PubMed Central

    Lemaire, Katleen; Quintens, Roel; Van Lommel, Leentje; Van Steen, Kristel; Leemans, Peter; Cleynen, Isabelle; Van Assche, Gert; Vermeire, Séverine; Geboes, Karel; Schuit, Frans; Rutgeerts, Paul

    2009-01-01

    Background Antimicrobial peptides (AMPs) protect the host intestinal mucosa against microorganisms. Abnormal expression of defensins was shown in inflammatory bowel disease (IBD), but it is not clear whether this is a primary defect. We investigated the impact of anti-inflammatory therapy with infliximab on the mucosal gene expression of AMPs in IBD. Methodology/Principal Findings Mucosal gene expression of 81 AMPs was assessed in 61 IBD patients before and 4–6 weeks after their first infliximab infusion and in 12 control patients, using Affymetrix arrays. Quantitative real-time reverse-transcription PCR and immunohistochemistry were used to confirm microarray data. The dysregulation of many AMPs in colonic IBD in comparison with control colons was widely restored by infliximab therapy, and only DEFB1 expression remained significantly decreased after therapy in the colonic mucosa of IBD responders to infliximab. In ileal Crohn's disease (CD), expression of two neuropeptides with antimicrobial activity, PYY and CHGB, was significantly decreased before therapy compared to control ileums, and ileal PYY expression remained significantly decreased after therapy in CD responders. Expression of the downregulated AMPs before and after treatment (DEFB1 and PYY) correlated with villin 1 expression, a gut epithelial cell marker, indicating that the decrease is a consequence of epithelial damage. Conclusions/Significance Our study shows that the dysregulation of AMPs in IBD mucosa is the consequence of inflammation, but may be responsible for perpetuation of inflammation due to ineffective clearance of microorganisms. PMID:19956723

  13. Comparative analysis of temporal gene expression patterns in the developing ovary of the embryonic chicken

    PubMed Central

    YU, Minli; XU, Yali; YU, Defu; YU, Debing; DU, Wenxing

    2015-01-01

    Many genes participate in the process of ovarian germ cell development, while the combined action mechanisms of these molecular regulators still need clarification. The present study was focused on determination of differentially expressed genes and gene functions at four critical time points in chicken ovarian development. Comparative transcriptional profiling of ovaries from embryonic day 5.5 (E5.5), E12.5, E15.5 and E18.5 was performed using an Affymetrix GeneChip chicken genome microarray. Differential expression patterns for genes specifically depleted and enriched in each stage were identified. The results showed that most of the up- and downregulated genes were involved in the metabolism of retinoic acid (RA) and synthesis of hormones. Among them, a higher number of up- and downregulated genes in the E15.5 ovary were identified as being involved in steroid biosynthesis and retinol metabolism, respectively. To validate gene changes, expressions of twelve candidate genes related to germ cell development were examined by real-time PCR and found to be consistent with the of GeneChip data. Moreover, the immunostaining results suggested that ovarian development during different stages was regulated by different genes. Furthermore, a Raldh2 knockdown chicken model was produced to investigate the fundamental role of Raldh2 in meiosis initiation. It was found that meiosis occurred abnormally in Raldh2 knockdown ovaries, but the inhibitory effect on meiosis was reversed by the addition of exogenous RA. This study offers insights into the profile of gene expression and mechanisms regulating ovarian development, especially the notable role of Raldh2 in meiosis initiation in the chicken. PMID:25736178

  14. Parallel Gene Expression Changes in Sarcoidosis Involving the Lacrimal Gland, Orbital Tissue, or Blood

    PubMed Central

    Rosenbaum, James T.; Choi, Dongseok; Wilson, David J.; Grossniklaus, Hans E.; Harrington, Christina A.; Sibley, Cailin H.; Dailey, Roger A.; Ng, John D.; Steele, Eric A.; Czyz, Craig N.; Foster, Jill A.; Tse, David; Alabiad, Chris; Dubovy, Sander; Parekh, Prashant; Harris, Gerald J.; Kazim, Michael; Patel, Payal; White, Valerie; Dolman, Peter; Korn, Bobby S.; Kikkawa, Don; Edward, Deepak P.; Alkatan, Hind; al-Hussain, Hailah; Yeatts, R. Patrick; Selva, Dinesh; Stauffer, Patrick; Planck, Stephen R.

    2016-01-01

    IMPORTANCE Sarcoidosis is a major cause of ocular or periocular inflammation. The pathogenesis of sarcoidosis is incompletely understood and diagnosis often requires a biopsy. OBJECTIVE To determine how gene expression in either orbital adipose tissue or the lacrimal gland affected by sarcoidosis compares with gene expression in other causes of orbital disease and how gene expression in tissue affected by sarcoidosis compares with gene expression in peripheral blood samples obtained from patients with sarcoidosis. DESIGN, SETTING, AND PARTICIPANTS In a multicenter, international, observational study, gene expression profiling of formalin-fixed biopsy specimens, using GeneChipp U133 Plus 2 microarrays (Affymetrix), was conducted between October 2012 and January 2014 on tissues biopsied from January 2000 through June 2013. Participants included 12 patients with orbital sarcoidosis (7 in adipose tissue; 5 affecting the lacrimal gland) as well as comparable tissue from 6 healthy individuals serving as controls or patients with thyroid eye disease, nonspecific orbital inflammation, or granulomatosis with polyangiitis. In addition, results were compared with gene expression in peripheral blood samples obtained from 12 historical individuals with sarcoidosis. MAIN OUTCOMES AND MEASURES Significantly differentially expressed transcripts defined as a minimum of a 1.5-fold increase or a comparable decrease and a false discovery rate of P < .05. RESULTS Signals from 2449 probe sets (transcripts from approximately 1522 genes) were significantly increased in the orbital adipose tissue from patients with sarcoidosis. Signals from 4050 probe sets (approximately 2619 genes) were significantly decreased. Signals from 3069 probe sets (approximately 2001 genes) were significantly higher and 3320 (approximately 2283 genes) were significantly lower in the lacrimal gland for patients with sarcoidosis. Ninety-two probe sets (approximately 69 genes) had significantly elevated signals and

  15. Trefoil factor 3: a novel serum marker identified by gene expression profiling in high-grade endometrial carcinomas.

    PubMed

    Bignotti, E; Ravaggi, A; Tassi, R A; Calza, S; Rossi, E; Falchetti, M; Romani, C; Bandiera, E; Odicino, F E; Pecorelli, S; Santin, A D

    2008-09-01

    This study identifies the genetic fingerprint of poorly differentiated endometrioid endometrial carcinomas (G3-EEC) and analyses the potential utility of trefoil factor 3 (TFF3) as novel serum marker in G3-EEC. Affymetrix microarrays were used to identify the gene expression patterns of 19 snap-frozen G3-EEC and 15 normal endometrium (NE) biopsies. Quantitative real-time PCR (qRT-PCR) and immunohistochemistry were used to validate TFF3 expression. Finally, TFF3 serum levels were determined by ELISA in 25 G3-EEC patients, 42 healthy controls, and in 13 endometrial hyperplasia patients. Hierarchical cluster analysis showed TFF3 as the top differentially expressed gene between 363 upregulated genes in G3-EEC, when compared with NE. Trefoil factor 3 gene expression levels analysed by qRT-PCR significantly correlated with Affymetrix results (P<0.001; rs=0.85). By immunohistochemistry, TFF3 protein was significatively more expressed in EEC compared with NE (P<0.01), with cytoplasmatic positivity in 79% G3-EEC and 18% NE. Patients harbouring G3-EECs had significantly higher TFF3 serum concentration by ELISA when compared with healthy patients (P<0.001) or patients harbouring endometrial hyperplasia (P=0.012). In conclusion, TFF3 is highly expressed at gene and protein level in G3-EEC. Further investigations on a wider set of samples are warranted to validate TFF3 as a novel serum marker for early detection and/or monitoring of G3-EEC patients.

  16. Identification of four soybean reference genes for gene expression normalization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gene expression analysis requires the use of reference genes stably expressed independently of specific tissues or environmental conditions. Housekeeping genes (e.g., actin, tubulin, ribosomal, polyubiquitin and elongation factor 1-alpha) are commonly used as reference genes with the assumption tha...

  17. Mitochondrial RNA granules: Compartmentalizing mitochondrial gene expression

    PubMed Central

    Jourdain, Alexis A.; Boehm, Erik; Maundrell, Kinsey

    2016-01-01

    In mitochondria, DNA replication, gene expression, and RNA degradation machineries coexist within a common nondelimited space, raising the question of how functional compartmentalization of gene expression is achieved. Here, we discuss the recently characterized “mitochondrial RNA granules,” mitochondrial subdomains with an emerging role in the regulation of gene expression. PMID:26953349

  18. Gene expression profiles in liver of mouse after chronic exposure to drinking water.

    PubMed

    Wu, Bing; Zhang, Yan; Zhao, Dayong; Zhang, Xuxiang; Kong, Zhiming; Cheng, Shupei

    2009-10-01

    cDNA micorarray approach was applied to hepatic transcriptional profile analysis in male mouse (Mus musculus, ICR) to assess the potential health effects of drinking water in Nanjing, China. Mice were treated with continuous exposure to drinking water for 90 days. Hepatic gene expression was analyzed with Affymetrix Mouse Genome 430A 2.0 arrays, and pathway analysis was carried out by Molecule Annotation System 2.0 and KEGG pathway database. A total of 836 genes were found to be significantly altered (1.5-fold, P < or = 0.05), including 294 up-regulated genes and 542 down-regulated genes. According to biological pathway analysis, drinking water exposure resulted in aberration of gene expression and biological pathways linked to xenobiotic metabolism, signal transduction, cell cycle and oxidative stress response. Further, deregulation of several genes associated with carcinogenesis or tumor progression including Ccnd1, Egfr, Map2k3, Mcm2, Orc2l and Smad2 was observed. Although transcription changes in identified genes are unlikely to be used as a sole indicator of adverse health effects, the results of this study could enhance our understanding of early toxic effects of drinking water exposure and support future studies on drinking water safety.

  19. Correlations Between Gene Expression and Mercury Levels in Blood of Boys With and Without Autism

    PubMed Central

    Green, Peter G.; Tian, Yingfang; Hertz-Picciotto, Irva; Pessah, Isaac N.; Hansen, Robin; Yang, Xiaowei; Teng, Jennifer; Gregg, Jeffrey P.; Ashwood, Paul; Van de Water, Judy; Sharp, Frank R.

    2009-01-01

    Gene expression in blood was correlated with mercury levels in blood of 2- to 5-year-old boys with autism (AU) compared to age-matched typically developing (TD) control boys. This was done to address the possibility that the two groups might metabolize toxicants, such as mercury, differently. RNA was isolated from blood and gene expression assessed on whole genome Affymetrix Human U133 expression microarrays. Mercury levels were measured using an inductively coupled plasma mass spectrometer. Analysis of covariance (ANCOVA) was performed and partial correlations between gene expression and mercury levels were calculated, after correcting for age and batch effects. To reduce false positives, only genes shared by the ANCOVA models were analyzed. Of the 26 genes that correlated with mercury levels in both AU and TD boys, 11 were significantly different between the groups (P(Diagnosis*Mercury) ≤ 0.05). The expression of a large number of genes (n = 316) correlated with mercury levels in TD but not in AU boys (P ≤ 0.05), the most represented biological functions being cell death and cell morphology. Expression of 189 genes correlated with mercury levels in AU but not in TD boys (P ≤ 0.05), the most represented biological functions being cell morphology, amino acid metabolism, and antigen presentation. These data and those in our companion study on correlation of gene expression and lead levels show that AU and TD children display different correlations between transcript levels and low levels of mercury and lead. These findings might suggest different genetic transcriptional programs associated with mercury in AU compared to TD children. Electronic supplementary material The online version of this article (doi:10.1007/s12640-009-9137-7) contains supplementary material, which is available to authorized users. PMID:19937285

  20. Altered Gene Expression Pattern in Peripheral Blood Mononuclear Cells in Patients with Acute Myocardial Infarction

    PubMed Central

    Kiliszek, Marek; Burzynska, Beata; Michalak, Marcin; Gora, Monika; Winkler, Aleksandra; Maciejak, Agata; Leszczynska, Agata; Gajda, Ewa; Kochanowski, Janusz; Opolski, Grzegorz

    2012-01-01

    Background Despite a substantial progress in diagnosis and therapy, acute myocardial infarction (MI) is a major cause of mortality in the general population. A novel insight into the pathophysiology of myocardial infarction obtained by studying gene expression should help to discover novel biomarkers of MI and to suggest novel strategies of therapy. The aim of our study was to establish gene expression patterns in leukocytes from acute myocardial infarction patients. Methods and Results Twenty-eight patients with ST-segment elevation myocardial infarction (STEMI) were included. The blood was collected on the 1st day of myocardial infarction, after 4–6 days, and after 6 months. Control group comprised 14 patients with stable coronary artery disease, without history of myocardial infarction. Gene expression analysis was performed with Affymetrix Human Gene 1.0 ST microarrays and GCS3000 TG system. Lists of genes showing altered expression levels (fold change >1.5, p<0.05) were submitted to Ingenuity Pathway Analysis. Gene lists from each group were examined for canonical pathways and molecular and cellular functions. Comparing acute phase of MI with the same patients after 6 months (stable phase) and with control group we found 24 genes with changed expression. In canonical analysis three pathways were highlighted: signaling of PPAR (peroxisome proliferator-activated receptor), IL-10 and IL-6 (interleukin 10 and 6). Conclusions In the acute phase of STEMI, dozens of genes from several pathways linked with lipid/glucose metabolism, platelet function and atherosclerotic plaque stability show altered expression. Up-regulation of SOCS3 and FAM20 genes in the first days of myocardial infarction is observed in the vast majority of patients. PMID:23185530

  1. Orbital pseudotumor can be a localized form of granulomatosis with polyangiitis as revealed by gene expression profiling.

    PubMed

    Rosenbaum, James T; Choi, Dongseok; Wilson, David J; Grossniklaus, Hans E; Harrington, Christina A; Sibley, Cailin H; Dailey, Roger A; Ng, John D; Steele, Eric A; Czyz, Craig N; Foster, Jill A; Tse, David; Alabiad, Chris; Dubovy, Sander; Parekh, Prashant K; Harris, Gerald J; Kazim, Michael; Patel, Payal J; White, Valerie A; Dolman, Peter J; Korn, Bobby S; Kikkawa, Don O; Edward, Deepak P; Alkatan, Hind M; al-Hussain, Hailah; Yeatts, R Patrick; Selva, Dinesh; Stauffer, Patrick; Planck, Stephen R

    2015-10-01

    Biopsies and ANCA testing for limited forms of granulomatosis with polyangiitis (GPA) are frequently non-diagnostic. We characterized gene expression in GPA and other causes of orbital inflammation. We tested the hypothesis that a sub-set of patients with non-specific orbital inflammation (NSOI, also known as pseudotumor) mimics a limited form of GPA. Formalin-fixed, paraffin-embedded orbital biopsies were obtained from controls (n=20) and patients with GPA (n=6), NSOI (n=25), sarcoidosis (n=7), or thyroid eye disease (TED) (n=20) and were divided into discovery and validation sets. Transcripts in the tissues were quantified using Affymetrix U133 Plus 2.0 microarrays. Distinct gene expression profiles for controls and subjects with GPA, TED, or sarcoidosis were evident by principal coordinate analyses. Compared with healthy controls, 285 probe sets had elevated signals in subjects with GPA and 1472 were decreased (>1.5-fold difference, false discovery rate adjusted p<0.05). The immunoglobulin family of genes had the most dramatic increase in expression. Although gene expression in GPA could be readily distinguished from gene expression in TED, sarcoidosis, or controls, a comparison of gene expression in GPA versus NSOI found no statistically significant differences. Thus, forms of orbital inflammation can be distinguished based on gene expression. NSOI/pseudotumor is heterogeneous but often may be an unrecognized, localized form of GPA. PMID:26163757

  2. Genetic Background Modulates Gene Expression Profile Induced by Skin Irradiation in Ptch1 Mice

    SciTech Connect

    Galvan, Antonella; Noci, Sara; Mancuso, Mariateresa; Pazzaglia, Simonetta; Saran, Anna; Dragani, Tommaso A.

    2008-12-01

    Purpose: Ptch1 germ-line mutations in mice predispose to radiation-induced basal cell carcinoma of the skin, with tumor incidence modulated by the genetic background. Here, we examined the possible mechanisms underlying skin response to radiation in F1 progeny of Ptch1{sup neo67/+} mice crossed with either skin tumor-susceptible (Car-S) or -resistant (Car-R) mice and X-irradiated (3 Gy) at 2 days of age or left untreated. Methods and Materials: We conducted a gene expression profile analysis in mRNA samples extracted from the skin of irradiated or control mice, using Affymetrix whole mouse genome expression array. Confirmation of the results was done using real-time reverse-transcriptase polymerase chain reaction. Results: Analysis of the gene expression profile of normal skin of F1 mice at 4 weeks of age revealed a similar basal profile in the nonirradiated mice, but alterations in levels of 71 transcripts in irradiated Ptch1{sup neo67/+} mice of the Car-R cross and modulation of only eight genes in irradiated Ptch1{sup neo67/+} mice of the Car-S cross. Conclusions: These results indicate that neonatal irradiation causes a persistent change in the gene expression profile of the skin. The tendency of mice genetically resistant to skin tumorigenesis to show a more complex pattern of transcriptional response to radiation than do genetically susceptible mice suggests a role for this response in genetic resistance to basal cell tumorigenesis.

  3. Identification of CD200+ colorectal cancer stem cells and their gene expression profile.

    PubMed

    Zhang, Shan-Shan; Huang, Zai-Wei; Li, Li-Xuan; Fu, Jin-Jin; Xiao, Bing

    2016-10-01

    CD200 is a cell surface glycoprotein that has been implicated in a variety of human cancer cells. It has been proposed as a cancer stem cell (CSC) marker in colon cancer and is closely related to tumor immunosuppression. However, there is little functional data supporting its role as a true CSC marker, and the mechanism by which CD200 contributes to colorectal cancer has not been elucidated. In the present study, CD200+ and CD200- COLO 205 colorectal cancer cells were sorted out by flow cytometry, and colonosphere formation and Transwell migration assays were performed. Affymetrix Human U133 Plus2.0 arrays were used to screen the gene expression profiles of CD200+ and CD200- colorectal cancer cells. The results suggest that there are differentially expressed genes between the two subpopulations, including several important genes that function in cell proliferation, metastasis, apoptosis and the immune response. Pathway analysis revealed that the Wnt, MAPK and calcium signaling pathways were differentially expressed between CD200+ and CD200- cells. Moreover, several key genes upregulated in CD200+ cells were also highly overexpressed in CD44+CD133+ colorectal stem cells compared to the CD44-CD133- fraction of the same cell line. In the present study, we showed for the first time a correlation between CD200 expression and the Wnt signaling pathway in colon cancer cells. PMID:27574016

  4. Gene expression in the mouse eye: an online resource for genetics using 103 strains of mice

    PubMed Central

    Lu, Lu; Freeman-Anderson, Natalie E.; Templeton, Justin P.; Nassr, Mohamed; Wang, Xusheng; Gu, Weikuan; Jiao, Yan; Williams, Robert W.

    2009-01-01

    Purpose Individual differences in patterns of gene expression account for much of the diversity of ocular phenotypes and variation in disease risk. We examined the causes of expression differences, and in their linkage to sequence variants, functional differences, and ocular pathophysiology. Methods mRNAs from young adult eyes were hybridized to oligomer microarrays (Affymetrix M430v2). Data were embedded in GeneNetwork with millions of single nucleotide polymorphisms, custom array annotation, and information on complementary cellular, functional, and behavioral traits. The data include male and female samples from 28 common strains, 68 BXD recombinant inbred lines, as well as several mutants and knockouts. Results We provide a fully integrated resource to map, graph, analyze, and test causes and correlations of differences in gene expression in the eye. Covariance in mRNA expression can be used to infer gene function, extract signatures for different cells or tissues, to define molecular networks, and to map quantitative trait loci that produce expression differences. These data can also be used to connect disease phenotypes with sequence variants. We demonstrate that variation in rhodopsin expression efficiently predicts candidate genes for eight uncloned retinal diseases, including WDR17 for the human RP29 locus. Conclusions The high level of strain variation in gene expression is a powerful tool that can be used to explore and test molecular networks underlying variation in structure, function, and disease susceptibility. The integration of these data into GeneNetwork provides users with a workbench to test linkages between sequence differences and eye structure and function. PMID:19727342

  5. Gene Expression in Peripheral Immune Cells following Cardioembolic Stroke Is Sexually Dimorphic

    PubMed Central

    Stamova, Boryana; Jickling, Glen C.; Ander, Bradley P.; Zhan, Xinhua; Liu, DaZhi; Turner, Renee; Ho, Carolyn; Khoury, Jane C.; Bushnell, Cheryl; Pancioli, Arthur; Jauch, Edward C.; Broderick, Joseph P.; Sharp, Frank R.

    2014-01-01

    Aims Epidemiological studies suggest that sex has a role in the pathogenesis of cardioembolic stroke. Since stroke is a vascular disease, identifying sexually dimorphic gene expression changes in blood leukocytes can inform on sex-specific risk factors, response and outcome biology. We aimed to examine the sexually dimorphic immune response following cardioembolic stroke by studying the differential gene expression in peripheral white blood cells. Methods and Results Blood samples from patients with cardioembolic stroke were obtained at ≤3 hours (prior to treatment), 5 hours and 24 hours (after treatment) after stroke onset (n = 23; 69 samples) and compared with vascular risk factor controls without symptomatic vascular diseases (n = 23, 23 samples) (ANCOVA, false discovery rate p≤0.05, |fold change| ≥1.2). mRNA levels were measured on whole-genome Affymetrix microarrays. There were more up-regulated than down-regulated genes in both sexes, and females had more differentially expressed genes than males following cardioembolic stroke. Female gene expression was associated with cell death and survival, cell-cell signaling and inflammation. Male gene expression was associated with cellular assembly, organization and compromise. Immune response pathways were over represented at ≤3, 5 and 24 h after stroke in female subjects but only at 24 h in males. Neutrophil-specific genes were differentially expressed at 3, 5 and 24 h in females but only at 5 h and 24 h in males. Conclusions There are sexually dimorphic immune cell expression profiles following cardioembolic stroke. Future studies are needed to confirm the findings using qRT-PCR in an independent cohort, to determine how they relate to risk and outcome, and to compare to other causes of ischemic stroke. PMID:25036109

  6. Analysis of human breast milk cells: gene expression profiles during pregnancy, lactation, involution, and mastitic infection.

    PubMed

    Sharp, Julie A; Lefèvre, Christophe; Watt, Ashalyn; Nicholas, Kevin R

    2016-05-01

    The molecular processes underlying human milk production and the effects of mastitic infection are largely unknown because of limitations in obtaining tissue samples. Determination of gene expression in normal lactating women would be a significant step toward understanding why some women display poor lactation outcomes. Here, we demonstrate the utility of RNA obtained directly from human milk cells to detect mammary epithelial cell (MEC)-specific gene expression. Milk cell RNA was collected from five time points (24 h prepartum during the colostrum period, midlactation, two involutions, and during a bout of mastitis) in addition to an involution series comprising three time points. Gene expression profiles were determined by use of human Affymetrix arrays. Milk cells collected during milk production showed that the most highly expressed genes were involved in milk synthesis (e.g., CEL, OLAH, FOLR1, BTN1A1, and ARG2), while milk cells collected during involution showed a significant downregulation of milk synthesis genes and activation of involution associated genes (e.g., STAT3, NF-kB, IRF5, and IRF7). Milk cells collected during mastitic infection revealed regulation of a unique set of genes specific to this disease state, while maintaining regulation of milk synthesis genes. Use of conventional epithelial cell markers was used to determine the population of MECs within each sample. This paper is the first to describe the milk cell transcriptome across the human lactation cycle and during mastitic infection, providing valuable insight into gene expression of the human mammary gland. PMID:26909879

  7. GeneChip expression profiling reveals the alterations of energy metabolism related genes in osteocytes under large gradient high magnetic fields.

    PubMed

    Wang, Yang; Chen, Zhi-Hao; Yin, Chun; Ma, Jian-Hua; Li, Di-Jie; Zhao, Fan; Sun, Yu-Long; Hu, Li-Fang; Shang, Peng; Qian, Ai-Rong

    2015-01-01

    The diamagnetic levitation as a novel ground-based model for simulating a reduced gravity environment has recently been applied in life science research. In this study a specially designed superconducting magnet with a large gradient high magnetic field (LG-HMF), which can provide three apparent gravity levels (μ-g, 1-g, and 2-g), was used to simulate a space-like gravity environment. Osteocyte, as the most important mechanosensor in bone, takes a pivotal position in mediating the mechano-induced bone remodeling. In this study, the effects of LG-HMF on gene expression profiling of osteocyte-like cell line MLO-Y4 were investigated by Affymetrix DNA microarray. LG-HMF affected osteocyte gene expression profiling. Differentially expressed genes (DEGs) and data mining were further analyzed by using bioinfomatic tools, such as DAVID, iReport. 12 energy metabolism related genes (PFKL, AK4, ALDOC, COX7A1, STC1, ADM, CA9, CA12, P4HA1, APLN, GPR35 and GPR84) were further confirmed by real-time PCR. An integrated gene interaction network of 12 DEGs was constructed. Bio-data mining showed that genes involved in glucose metabolic process and apoptosis changed notablly. Our results demostrated that LG-HMF affected the expression of energy metabolism related genes in osteocyte. The identification of sensitive genes to special environments may provide some potential targets for preventing and treating bone loss or osteoporosis. PMID:25635858

  8. GeneChip Expression Profiling Reveals the Alterations of Energy Metabolism Related Genes in Osteocytes under Large Gradient High Magnetic Fields

    PubMed Central

    Wang, Yang; Chen, Zhi-Hao; Yin, Chun; Ma, Jian-Hua; Li, Di-Jie; Zhao, Fan; Sun, Yu-Long; Hu, Li-Fang; Shang, Peng; Qian, Ai-Rong

    2015-01-01

    The diamagnetic levitation as a novel ground-based model for simulating a reduced gravity environment has recently been applied in life science research. In this study a specially designed superconducting magnet with a large gradient high magnetic field (LG-HMF), which can provide three apparent gravity levels (μ-g, 1-g, and 2-g), was used to simulate a space-like gravity environment. Osteocyte, as the most important mechanosensor in bone, takes a pivotal position in mediating the mechano-induced bone remodeling. In this study, the effects of LG-HMF on gene expression profiling of osteocyte-like cell line MLO-Y4 were investigated by Affymetrix DNA microarray. LG-HMF affected osteocyte gene expression profiling. Differentially expressed genes (DEGs) and data mining were further analyzed by using bioinfomatic tools, such as DAVID, iReport. 12 energy metabolism related genes (PFKL, AK4, ALDOC, COX7A1, STC1, ADM, CA9, CA12, P4HA1, APLN, GPR35 and GPR84) were further confirmed by real-time PCR. An integrated gene interaction network of 12 DEGs was constructed. Bio-data mining showed that genes involved in glucose metabolic process and apoptosis changed notablly. Our results demostrated that LG-HMF affected the expression of energy metabolism related genes in osteocyte. The identification of sensitive genes to special environments may provide some potential targets for preventing and treating bone loss or osteoporosis. PMID:25635858

  9. Gene expression and pathway analysis of human hepatocellular carcinoma cells treated with cadmium.

    PubMed

    Cartularo, Laura; Laulicht, Freda; Sun, Hong; Kluz, Thomas; Freedman, Jonathan H; Costa, Max

    2015-11-01

    Cadmium (Cd) is a toxic and carcinogenic metal naturally occurring in the Earth's crust. A common route of human exposure is via diet and cadmium accumulates in the liver. The effects of Cd exposure on gene expression in human hepatocellular carcinoma (HepG2) cells were examined in this study. HepG2 cells were acutely-treated with 0.1, 0.5, or 1.0 μM Cd for 24h; or chronically-treated with 0.01, 0.05, or 0.1 μM Cd for three weeks and gene expression analysis was performed using Affymetrix GeneChip® Human Gene 1.0 ST Arrays. Acute and chronic exposures significantly altered the expression of 333 and 181 genes, respectively. The genes most upregulated by acute exposure included several metallothioneins. Downregulated genes included the monooxygenase CYP3A7, involved in drug and lipid metabolism. In contrast, CYP3A7 was upregulated by chronic Cd exposure, as was DNAJB9, an anti-apoptotic J protein. Genes downregulated following chronic exposure included the transcriptional regulator early growth response protein 1. Ingenuity Pathway Analysis revealed that the top networks altered by acute exposure were lipid metabolism, small molecule biosynthesis, cell morphology, organization, and development; while top networks altered by chronic exposure were organ morphology, cell cycle, cell signaling, and renal and urological diseases/cancer. Many of the dysregulated genes play important roles in cellular growth, proliferation, and apoptosis, and may be involved in carcinogenesis. In addition to gene expression changes, HepG2 cells treated with cadmium for 24h indicated a reduction in global levels of histone methylation and acetylation that persisted 72 h post-treatment.

  10. Effect of free thymol on differential gene expression in gastric mucosa of the young pig.

    PubMed

    Colombo, M; Priori, D; Gandolfi, G; Boatto, G; Nieddu, M; Bosi, P; Trevisi, P

    2014-05-01

    Thymol is the most common molecule in thyme and has been proposed as an oral alternative to antibiotics in the feed of pigs and broilers. The knowledge of the in vivo physiological effects of thymol on tissues is limited, particularly its impact on the gastric mucosa, where it is primarily absorbed when it is orally supplied. In this study, thymol (TH, 50 mg/ kg BW) or a placebo (CO) was introduced directly into the stomach of 8 weaned pigs that were slaughtered 12 h later and sampled for gastric oxyntic and pyloric mucosa. The analysis of whole transcript expression was performed using Affymetrix© Porcine Gene 1.1 ST array strips. Affymetrix Transcripts IDs were associated with 13 406 human gene names based on Sus scrofa Ensemble. Gene Set Enrichment Analysis was performed, comparing TH and CO pigs. For each gene set, the normalized enrichment score (NES) was defined as significant when the false discovery rate % was <25 and the P-value of NES was <0.05. In response to TH, 72 and 19 gene sets were significantly enriched in the oxyntic and pyloric mucosa, respectively. Several gene sets involved in mitosis and its regulation ranked near the top, primarily in the oxyntic mucosa; the gene set DIGESTION ranked first and ninth in the pyloric and oxyntic mucosa, respectively. Within this group, somatostatin (SST), SST receptors, peptide transporter 1 (SLC15A1) and calpain 9 (gastrointestinal tract-specific calpain) were the most strongly upregulated genes. Thymol reduced the enrichment of 120 and 59 gene sets in the oxyntic and pyloric mucosa, respectively. Several gene sets related to ion transport and channeling and aqueous pores across membranes, including short transient receptor potential (TRP) channel 4, potassium voltage-gated channel members 1 and 2, and ryanodine receptors 2 and 3, were less enriched. The downregulation of these genes sensitive to thymol in vitro could depend on the thymol dose and contact with the gastric tissues that causes an adaptive

  11. Effects of weak, low-frequency pulsed electromagnetic fields (BEMER type) on gene expression of human mesenchymal stem cells and chondrocytes: an in vitro study.

    PubMed

    Walther, Markus; Mayer, Florian; Kafka, Wolf; Schütze, Norbert

    2007-01-01

    In vitro effects of electromagnetic fields appear to be related to the type of electromagnetic field applied. Previously, we showed that human osteoblasts display effects of BEMER type electromagnetic field (BTEMF) on gene regulation. Here, we analyze effects of BTEMF on gene expression in human mesenchymal stem cells and chondrocytes. Primary mesenchymal stem cells from bone marrow and the chondrocyte cell line C28I2 were stimulated 5 times at 12-h intervals for 8 min each with BTEMF. RNA from treated and control cells was analyzed for gene expression using the affymetrix chip HG-U133A. A limited number of regulated gene products from both cell types mainly affect cell metabolism and cell matrix structure. There was no increased expression of cancer-related genes. RT-PCR analysis of selected transcripts partly confirmed array data. Results indicate that BTEMF in human mesenchymal stem cells and chondrocytes provide the first indications to understanding therapeutic effects achieved with BTEMF stimulation.

  12. Gene Expression Signatures in Polyarticular Juvenile Idiopathic Arthritis Demonstrate Disease Heterogeneity and Offer a Molecular Classification of Disease Subsets

    PubMed Central

    Griffin, Thomas A.; Barnes, Michael G.; Ilowite, Norman T.; Olson, Judyann C.; Sherry, David D.; Gottlieb, Beth S.; Aronow, Bruce J.; Pavlidis, Paul; Hinze, Claas; Thornton, Sherry; Thompson, Susan D.; Grom, Alexei A.; Colbert, Robert A.; Glass, David N.

    2009-01-01

    Objective Microarray analysis was used to determine whether children with recent onset polyarticular juvenile idiopathic arthritis (JIA) exhibit biologically or clinically informative gene expression signatures in peripheral blood mononuclear cells (PBMC). Methods Peripheral blood samples were obtained from 59 healthy children and 61 children with polyarticular JIA prior to treatment with second-line medications, such as methotrexate or biological agents. RNA was extracted from Ficoll-isolated mononuclear cells, fluorescently labeled and hybridized to Affymetrix U133 Plus 2.0 GeneChips. Data were analyzed using ANOVA at a 5% false discovery rate threshold after Robust Multi-Array Average pre-processing and Distance Weighted Discrimination normalization. Results Initial analysis revealed 873 probe sets for genes that were differentially expressed between polyarticular JIA and controls. Hierarchical clustering of these probe sets distinguished three subgroups within polyarticular JIA. Prototypical subjects within each subgroup were identified and used to define subgroup-specific gene expression signatures. One of these signatures was associated with monocyte markers, another with transforming growth factor β-inducible genes, and a third with immediate-early genes. Correlation of gene expression signatures with clinical and biological features of JIA subgroups suggests relevance to aspects of disease activity and supports the division of polyarticular JIA into distinct subsets. Conclusions PBMC gene expression signatures in recent onset polyarticular JIA reflect discrete disease processes and offer a molecular classification of disease. PMID:19565504

  13. A Replication Study for Genome-Wide Gene Expression Levels in Two Layer Lines Elucidates Differentially Expressed Genes of Pathways Involved in Bone Remodeling and Immune Responsiveness

    PubMed Central

    Habig, Christin; Geffers, Robert; Distl, Ottmar

    2014-01-01

    The current replication study confirmed significant differences in gene expression profiles of the cerebrum among the two commercial layer lines Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB). Microarray analyses were performed for 30 LSL and another 30 LB laying hens kept in the small group housing system Eurovent German. A total of 14,103 microarray probe sets using customized Affymetrix ChiGene-1_0-st Arrays with 20,399 probe sets were differentially expressed among the two layer lines LSL and LB (FDR adjusted P-value <0.05). An at least 2-fold change in expression levels could be observed for 388 of these probe sets. In LSL, 214 of the 388 probe sets were down- and 174 were up-regulated and vice versa for the LB layer line. Among the 174 up-regulated probe sets in LSL, we identified 51 significantly enriched Gene ontology (GO) terms of the biological process category. A total of 63 enriched GO-terms could be identified for the 214 down-regulated probe sets of the layer line LSL. We identified nine genes significantly differentially expressed between the two layer lines in both microarray experiments. These genes play a crucial role in protection of neuronal cells from oxidative stress, bone mineral density and immune response among the two layer lines LSL and LB. Thus, the different regulation of these genes may significantly contribute to phenotypic trait differences among these layer lines. In conclusion, these novel findings provide a basis for further research to improve animal welfare in laying hens and these layer lines may be of general interest as an animal model. PMID:24922511

  14. Maternal age effects on myometrial expression of contractile proteins, uterine gene expression, and contractile activity during labor in the rat

    PubMed Central

    Elmes, Matthew; Szyszka, Alexandra; Pauliat, Caroline; Clifford, Bethan; Daniel, Zoe; Cheng, Zhangrui; Wathes, Claire; McMullen, Sarah

    2015-01-01

    Advanced maternal age of first time pregnant mothers is associated with prolonged and dysfunctional labor and significant risk of emergency cesarean section. We investigated the influence of maternal age on myometrial contractility, expression of contractile associated proteins (CAPs), and global gene expression in the parturient uterus. Female Wistar rats either 8 (YOUNG n = 10) or 24 (OLDER n = 10) weeks old were fed laboratory chow, mated, and killed during parturition. Myometrial strips were dissected to determine contractile activity, cholesterol (CHOL) and triglycerides (TAG) content, protein expression of connexin-43 (GJA1), prostaglandin-endoperoxide synthase 2 (PTGS2), and caveolin 1 (CAV-1). Maternal plasma concentrations of prostaglandins PGE2, PGF2α, and progesterone were determined by RIA. Global gene expression in uterine samples was compared using Affymetrix Genechip Gene 2.0 ST arrays and Ingenuity Pathway analysis (IPA). Spontaneous contractility in myometrium exhibited by YOUNG rats was threefold greater than OLDER animals (P < 0.027) but maternal age had no significant effect on myometrial CAP expression, lipid profiles, or pregnancy-related hormones. OLDER myometrium increased contractile activity in response to PGF2α, phenylephrine, and carbachol, a response absent in YOUNG rats (all P < 0.002). Microarray analysis identified that maternal age affected expression of genes related to immune and inflammatory responses, lipid transport and metabolism, steroid metabolism, tissue remodeling, and smooth muscle contraction. In conclusion YOUNG laboring rat myometrium seems primed to contract maximally, whereas activity is blunted in OLDER animals and requires stimulation to meet contractile potential. Further work investigating maternal age effects on myometrial function is required with focus on lipid metabolism and inflammatory pathways. PMID:25876907

  15. Amniotic fluid RNA gene expression profiling provides insights into the phenotype of Turner syndrome.

    PubMed

    Massingham, Lauren J; Johnson, Kirby L; Scholl, Thomas M; Slonim, Donna K; Wick, Heather C; Bianchi, Diana W

    2014-09-01

    Turner syndrome is a sex chromosome aneuploidy with characteristic malformations. Amniotic fluid, a complex biological material, could contribute to the understanding of Turner syndrome pathogenesis. In this pilot study, global gene expression analysis of cell-free RNA in amniotic fluid supernatant was utilized to identify specific genes/organ systems that may play a role in Turner syndrome pathophysiology. Cell-free RNA from amniotic fluid of five mid-trimester Turner syndrome fetuses and five euploid female fetuses matched for gestational age was extracted, amplified, and hybridized onto Affymetrix(®) U133 Plus 2.0 arrays. Significantly differentially regulated genes were identified using paired t tests. Biological interpretation was performed using Ingenuity Pathway Analysis and BioGPS gene expression atlas. There were 470 statistically significantly differentially expressed genes identified. They were widely distributed across the genome. XIST was significantly down-regulated (p < 0.0001); SHOX was not differentially expressed. One of the most highly represented organ systems was the hematologic/immune system, distinguishing the Turner syndrome transcriptome from other aneuploidies we previously studied. Manual curation of the differentially expressed gene list identified genes of possible pathologic significance, including NFATC3, IGFBP5, and LDLR. Transcriptomic differences in the amniotic fluid of Turner syndrome fetuses are due to genome-wide dysregulation. The hematologic/immune system differences may play a role in early-onset autoimmune dysfunction. Other genes identified with possible pathologic significance are associated with cardiac and skeletal systems, which are known to be affected in females with Turner syndrome. The discovery-driven approach described here may be useful in elucidating novel mechanisms of disease in Turner syndrome. PMID:24850140

  16. Amniotic fluid RNA gene expression profiling provides insights into the phenotype of Turner syndrome.

    PubMed

    Massingham, Lauren J; Johnson, Kirby L; Scholl, Thomas M; Slonim, Donna K; Wick, Heather C; Bianchi, Diana W

    2014-09-01

    Turner syndrome is a sex chromosome aneuploidy with characteristic malformations. Amniotic fluid, a complex biological material, could contribute to the understanding of Turner syndrome pathogenesis. In this pilot study, global gene expression analysis of cell-free RNA in amniotic fluid supernatant was utilized to identify specific genes/organ systems that may play a role in Turner syndrome pathophysiology. Cell-free RNA from amniotic fluid of five mid-trimester Turner syndrome fetuses and five euploid female fetuses matched for gestational age was extracted, amplified, and hybridized onto Affymetrix(®) U133 Plus 2.0 arrays. Significantly differentially regulated genes were identified using paired t tests. Biological interpretation was performed using Ingenuity Pathway Analysis and BioGPS gene expression atlas. There were 470 statistically significantly differentially expressed genes identified. They were widely distributed across the genome. XIST was significantly down-regulated (p < 0.0001); SHOX was not differentially expressed. One of the most highly represented organ systems was the hematologic/immune system, distinguishing the Turner syndrome transcriptome from other aneuploidies we previously studied. Manual curation of the differentially expressed gene list identified genes of possible pathologic significance, including NFATC3, IGFBP5, and LDLR. Transcriptomic differences in the amniotic fluid of Turner syndrome fetuses are due to genome-wide dysregulation. The hematologic/immune system differences may play a role in early-onset autoimmune dysfunction. Other genes identified with possible pathologic significance are associated with cardiac and skeletal systems, which are known to be affected in females with Turner syndrome. The discovery-driven approach described here may be useful in elucidating novel mechanisms of disease in Turner syndrome.

  17. Amniotic fluid RNA gene expression profiling provides insights into the phenotype of Turner syndrome

    PubMed Central

    Johnson, Kirby L.; Scholl, Thomas M.; Slonim, Donna K.; Wick, Heather C.; Bianchi, Diana W.

    2015-01-01

    Background Turner syndrome is a sex chromosome aneuploidy with characteristic malformations. Amniotic fluid, a complex biological material, could contribute to the understanding of Turner syndrome pathogenesis. In this pilot study, global gene expression analysis of cell-free RNA in amniotic fluid supernatant was utilized to identify specific genes/organ systems that may play a role in Turner syndrome pathophysiology. Methods Cell-free RNA from amniotic fluid of five mid-trimester Turner syndrome fetuses and five euploid female fetuses matched for gestational age was extracted, amplified, and hybridized onto Affymetrix® U133 Plus 2.0 arrays. Significantly differentially regulated genes were identified using paired t-tests. Biological interpretation was performed using Ingenuity Pathway Analysis and BioGPS gene expression atlas. Results There were 470 statistically significantly differentially expressed genes identified. They were widely distributed across the genome. XIST was significantly down-regulated (p<0.0001); SHOX was not differentially expressed. One of the most highly represented organ systems was the hematologic/immune system, distinguishing the Turner syndrome transcriptome from other aneuploidies we previously studied. Manual curation of the differentially expressed gene list identified genes of possible pathologic significance, including NFATC3, IGFBP5, and LDLR. Conclusions Transcriptomic differences in the amniotic fluid of Turner syndrome fetuses are due to genome-wide dysregulation. The hematologic/immune system differences may play a role in early-onset autoimmune dysfunction. Other genes identified with possible pathologic significance are associated with cardiac and skeletal systems, which are known to be affected in females with Turner syndrome. The discovery-driven approach described here may be useful in elucidating novel mechanisms of disease in Turner syndrome. PMID:24850140

  18. IL-17A mediates a selective gene expression profile in asthmatic human airway smooth muscle cells.

    PubMed

    Dragon, Stéphane; Hirst, Stuart J; Lee, Tak H; Gounni, Abdelilah S

    2014-06-01

    Airway smooth muscle (ASM) cells are thought to contribute to the pathogenesis of allergic asthma by orchestrating and perpetuating airway inflammation and remodeling responses. In this study, we evaluated the IL-17RA signal transduction and gene expression profile in ASM cells from subjects with mild asthma and healthy individuals. Human primary ASM cells were treated with IL-17A and probed by the Affymetrix GeneChip array, and gene targets were validated by real-time quantitative RT-PCR. Genomic analysis underlined the proinflammatory nature of IL-17A, as multiple NF-κB regulatory factors and chemokines were induced in ASM cells. Transcriptional regulators consisting of primary response genes were overrepresented and displayed dynamic expression profiles. IL-17A poorly enhanced IL-1β or IL-22 gene responses in ASM cells from both subjects with mild asthma and healthy donors. Interestingly, protein modifications to the NF-κB regulatory network were not observed after IL-17A stimulation, although oscillations in IκBε expression were detected. ASM cells from subjects with mild asthma up-regulated more genes with greater overall variability in response to IL-17A than from healthy donors. Finally, in response to IL-17A, ASM cells displayed rapid activation of the extracellular signal-regulated kinase/ribosomal S6 kinase signaling pathway and increased nuclear levels of phosphorylated extracellular signal-regulated kinase. Taken together, our results suggest that IL-17A mediated modest gene expression response, which, in cooperation with the NF-κB signaling network, may regulate the gene expression profile in ASM cells.

  19. Clinical Omics Analysis of Colorectal Cancer Incorporating Copy Number Aberrations and Gene Expression Data

    PubMed Central

    Yoshida, Tsuyoshi; Kobayashi, Takumi; Itoda, Masaya; Muto, Taika; Miyaguchi, Ken; Mogushi, Kaoru; Shoji, Satoshi; Shimokawa, Kazuro; Iida, Satoru; Uetake, Hiroyuki; Ishikawa, Toshiaki; Sugihara, Kenichi; Mizushima, Hiroshi; Tanaka, Hiroshi

    2010-01-01

    Background: Colorectal cancer (CRC) is one of the most frequently occurring cancers in Japan, and thus a wide range of methods have been deployed to study the molecular mechanisms of CRC. In this study, we performed a comprehensive analysis of CRC, incorporating copy number aberration (CRC) and gene expression data. For the last four years, we have been collecting data from CRC cases and organizing the information as an “omics” study by integrating many kinds of analysis into a single comprehensive investigation. In our previous studies, we had experienced difficulty in finding genes related to CRC, as we observed higher noise levels in the expression data than in the data for other cancers. Because chromosomal aberrations are often observed in CRC, here, we have performed a combination of CNA analysis and expression analysis in order to identify some new genes responsible for CRC. This study was performed as part of the Clinical Omics Database Project at Tokyo Medical and Dental University. The purpose of this study was to investigate the mechanism of genetic instability in CRC by this combination of expression analysis and CNA, and to establish a new method for the diagnosis and treatment of CRC. Materials and methods: Comprehensive gene expression analysis was performed on 79 CRC cases using an Affymetrix Gene Chip, and comprehensive CNA analysis was performed using an Affymetrix DNA Sty array. To avoid the contamination of cancer tissue with normal cells, laser micro-dissection was performed before DNA/RNA extraction. Data analysis was performed using original software written in the R language. Result: We observed a high percentage of CNA in colorectal cancer, including copy number gains at 7, 8q, 13 and 20q, and copy number losses at 8p, 17p and 18. Gene expression analysis provided many candidates for CRC-related genes, but their association with CRC did not reach the level of statistical significance. The combination of CNA and gene expression analysis

  20. Gene expression profile in streptozotocin rat model for sporadic Alzheimer's disease.

    PubMed

    Grünblatt, E; Hoyer, S; Riederer, P

    2004-03-01

    Sporadic Alzheimer's disease (SAD), a progressive neurodegenerative disease, is the most common cause of dementia. The etiology of the disease is still unknown, but it is suspected to be a concert of genetic and environmental factors. Intracerebroventricular injection of streptozotocin (STZ), which inhibits insulin receptor function, develops long-term and progressive deficits in learning, memory and cognitive behavior as well as biochemical changes and neuronal degeneration in rats similar to SAD. Micro-array analysis provides a genome-wide, non-biased study of gene expression patterns. The aim of this study was to investigate the gene expression pattern in the STZ animal model for SAD. RNA from rat cortex, striatum and cerebellum were analyzed for gene expression pattern via Affymetrix neurobiology chip-array and confirmed by real-time RT-PCR. Genes such as potassium channels, GABA receptors and glutamate transporter were up regulated, while insulin-like growth factor receptor was down regulated in STZ rats. These pathways may reveal molecular events causing the neuronal death in SAD. PMID:14991460

  1. Chromosomal patterns of gene expression from microarray data: methodology, validation and clinical relevance in gliomas

    PubMed Central

    Turkheimer, Federico E; Roncaroli, Federico; Hennuy, Benoit; Herens, Christian; Nguyen, Minh; Martin, Didier; Evrard, Annick; Bours, Vincent; Boniver, Jacques; Deprez, Manuel

    2006-01-01

    Background Expression microarrays represent a powerful technique for the simultaneous investigation of thousands of genes. The evidence that genes are not randomly distributed in the genome and that their coordinated expression depends on their position on chromosomes has highlighted the need for mathematical approaches to exploit this dependency for the analysis of expression data-sets. Results We have devised a novel mathematical technique (CHROMOWAVE) based on the Haar wavelet transform and applied it to a dataset obtained with the Affymetrix® HG-U133_Plus_2 array in 27 gliomas. CHROMOWAVE generated multi-chromosomal pattern featuring low expression in chromosomes 1p, 4, 9q, 13, 18, and 19q. This pattern was not only statistically robust but also clinically relevant as it was predictive of favourable outcome. This finding was replicated on a data-set independently acquired by another laboratory. FISH analysis indicated that monosomy 1p and 19q was a frequent feature of tumours displaying the CHROMOWAVE pattern but that allelic loss on chromosomes 4, 9q, 13 and 18 was much less common. Conclusion The ability to detect expression changes of spatially related genes and to map their position on chromosomes makes CHROMOWAVE a valuable screening method for the identification and display of regional gene expression changes of clinical relevance. In this study, FISH data showed that monosomy was frequently associated with diffuse low gene expression on chromosome 1p and 19q but not on chromosomes 4, 9q, 13 and 18. Comparative genomic hybridisation, allelic polymorphism analysis and methylation studies are in progress in order to identify the various mechanisms involved in this multi-chromosomal expression pattern. PMID:17140431

  2. Comparison of Gene Expression and Genome-Wide DNA Methylation Profiling between Phenotypically Normal Cloned Pigs and Conventionally Bred Controls

    PubMed Central

    Li, Shengting; Li, Jian; Lin, Lin; Nielsen, Anders Lade; Sørensen, Charlotte Brandt; Vajta, Gábor; Wang, Jun; Zhang, Xiuqing; Du, Yutao; Yang, Huanming; Bolund, Lars

    2011-01-01

    Animal breeding via Somatic Cell Nuclear Transfer (SCNT) has enormous potential in agriculture and biomedicine. However, concerns about whether SCNT animals are as healthy or epigenetically normal as conventionally bred ones are raised as the efficiency of cloning by SCNT is much lower than natural breeding or In-vitro fertilization (IVF). Thus, we have conducted a genome-wide gene expression and DNA methylation profiling between phenotypically normal cloned pigs and control pigs in two tissues (muscle and liver), using Affymetrix Porcine expression array as well as modified methylation-specific digital karyotyping (MMSDK) and Solexa sequencing technology. Typical tissue-specific differences with respect to both gene expression and DNA methylation were observed in muscle and liver from cloned as well as control pigs. Gene expression profiles were highly similar between cloned pigs and controls, though a small set of genes showed altered expression. Cloned pigs presented a more different pattern of DNA methylation in unique sequences in both tissues. Especially a small set of genomic sites had different DNA methylation status with a trend towards slightly increased methylation levels in cloned pigs. Molecular network analysis of the genes that contained such differential methylation loci revealed a significant network related to tissue development. In conclusion, our study showed that phenotypically normal cloned pigs were highly similar with normal breeding pigs in their gene expression, but moderate alteration in DNA methylation aspects still exists, especially in certain unique genomic regions. PMID:22022462

  3. Differential gene expression in ovaries of pregnant pigs with high and low prolificacy levels and identification of candidate genes for litter size.

    PubMed

    Fernandez-Rodriguez, Amanda; Munoz, Maria; Fernandez, Almudena; Pena, Ramona N; Tomas, Anna; Noguera, Jose L; Ovilo, Cristina; Fernandez, Ana I

    2011-02-01

    Previous results from a genome scan in an F(2) Iberian × Meishan pig intercross showed several chromosome regions associated with litter size traits in this species. In order to identify candidate genes underlying these quantitative trait loci (QTL), we performed an ovary gene expression analysis during the sow's pregnancy. F(2) sows were ranked by their estimated breeding values for prolificacy: six sows with the highest estimated breeding value (EBV) (i.e., high prolificacy) and six sows with the lowest EBV (low prolificacy) were selected. Samples were hybridized using an Affymetrix GeneChip porcine genome array. Statistical analysis with a mixed model approach identified 221 differentially expressed probes, representing 189 genes. These genes were functionally annotated in order to identify genetic pathways overrepresented in this list. Among the functional groups most represented was, in first position, immune system response activation against external stimulus. The second group consisted of integrated genes that regulate maternal homeostasis by complement and coagulation cascades. A third group was involved in lipid and fatty acid enzymes of metabolic processes, which participate in the steroidogenesis pathway. In order to identify powerful candidate genes for prolificacy, the second approach of this study was to merge microarray data with the QTL positional information affecting litter size, previously detected in the same experimental cross. As a result, we have identified 27 differentially expressed genes colocalizing with QTL for litter size traits, which fulfill the biological, positional, and functional criteria. PMID:20926806

  4. Gene expression profiling of CD34+ cells identifies a molecular signature of chronic myeloid leukemia blast crisis.

    PubMed

    Zheng, C; Li, L; Haak, M; Brors, B; Frank, O; Giehl, M; Fabarius, A; Schatz, M; Weisser, A; Lorentz, C; Gretz, N; Hehlmann, R; Hochhaus, A; Seifarth, W

    2006-06-01

    Despite recent success in the treatment of early-stage disease, blastic phase (BP) of chronic myeloid leukemia (CML) that is characterized by rapid expansion of therapy-refractory and differentiation-arrested blasts, remains a therapeutic challenge. The development of resistance upon continuous administration of imatinib mesylate is associated with poor prognosis pointing to the need for alternative therapeutic strategies and a better understanding of the molecular mechanisms underlying disease progression. To identify transcriptional signatures that may explain pathological characteristics and aggressive behavior of BP blasts, we performed comparative gene expression profiling on CD34+ Ph+ cells purified from patients with untreated newly diagnosed chronic phase CML (CP, n=11) and from patients in BP (n=9) using Affymetrix oligonucleotide arrays. Supervised microarray data analysis revealed 114 differentially expressed genes (P<10(-4)), 34 genes displaying more than two-fold transcriptional changes when comparing CP and BP groups. While 24 of these genes were downregulated, 10 genes, especially suppressor of cytokine signalling 2 (SOCS2), CAMPATH-1 antigen (CD52), and four human leukocyte antigen-related genes were strongly overexpressed in BP. Expression of selected genes was validated by real-time-polymerase chain reaction and flow cytometry. Our data suggest the existence of a common gene expression profile of CML-BP and provide new insight into the molecular phenotype of blasts associated with disease progression and high malignancy. PMID:16617318

  5. Comparison of In Vivo Gene Expression Profiling of RPE/Choroid following Intravitreal Injection of Dexamethasone and Triamcinolone Acetonide.

    PubMed

    Smit-McBride, Zeljka; Moisseiev, Elad; Modjtahedi, Sara P; Telander, David G; Hjelmeland, Leonard M; Morse, Lawrence S

    2016-01-01

    Purpose. To identify retinal pigment epithelium (RPE)/choroid genes and their relevant expression pathways affected by intravitreal injections of dexamethasone and triamcinolone acetonide in mice at clinically relevant time points for patient care. Methods. Differential gene expression of over 34,000 well-characterized mouse genes in the RPE/choroid of 6-week-old C57BL/6J mice was analyzed after intravitreal steroid injections at 1 week and 1 month postinjection, using Affymetrix Mouse Genome 430 2.0 microarrays. The data were analyzed using GeneSpring GX 12.5 and Ingenuity Pathway Analysis (IPA) microarray analysis software for biologically relevant changes. Results. Both triamcinolone and dexamethasone caused differential activation of genes involved in "Circadian Rhythm Signaling" pathway at both time points tested. Triamcinolone (TAA) uniquely induced significant changes in gene expression in "Calcium Signaling" (1 week) and "Glutamate Receptor Signaling" pathways (1 month). In contrast, dexamethasone (Dex) affected the "GABA Receptor Signaling" (1 week) and "Serotonin Receptor Signaling" (1 month) pathways. Understanding how intraocular steroids affect the gene expression of RPE/choroid is clinically relevant. Conclusions. This in vivo study has elucidated several genes and pathways that are potentially altering the circadian rhythms and several other neurotransmitter pathways in RPE/choroid during intravitreal steroid injections, which likely has consequences in the dysregulation of RPE function and neurodegeneration of the retina. PMID:27429799

  6. Comparison of In Vivo Gene Expression Profiling of RPE/Choroid following Intravitreal Injection of Dexamethasone and Triamcinolone Acetonide

    PubMed Central

    Smit-McBride, Zeljka; Moisseiev, Elad; Modjtahedi, Sara P.; Telander, David G.; Hjelmeland, Leonard M.; Morse, Lawrence S.

    2016-01-01

    Purpose. To identify retinal pigment epithelium (RPE)/choroid genes and their relevant expression pathways affected by intravitreal injections of dexamethasone and triamcinolone acetonide in mice at clinically relevant time points for patient care. Methods. Differential gene expression of over 34,000 well-characterized mouse genes in the RPE/choroid of 6-week-old C57BL/6J mice was analyzed after intravitreal steroid injections at 1 week and 1 month postinjection, using Affymetrix Mouse Genome 430 2.0 microarrays. The data were analyzed using GeneSpring GX 12.5 and Ingenuity Pathway Analysis (IPA) microarray analysis software for biologically relevant changes. Results. Both triamcinolone and dexamethasone caused differential activation of genes involved in “Circadian Rhythm Signaling” pathway at both time points tested. Triamcinolone (TAA) uniquely induced significant changes in gene expression in “Calcium Signaling” (1 week) and “Glutamate Receptor Signaling” pathways (1 month). In contrast, dexamethasone (Dex) affected the “GABA Receptor Signaling” (1 week) and “Serotonin Receptor Signaling” (1 month) pathways. Understanding how intraocular steroids affect the gene expression of RPE/choroid is clinically relevant. Conclusions. This in vivo study has elucidated several genes and pathways that are potentially altering the circadian rhythms and several other neurotransmitter pathways in RPE/choroid during intravitreal steroid injections, which likely has consequences in the dysregulation of RPE function and neurodegeneration of the retina. PMID:27429799

  7. Protective effects of L-selenomethionine on space radiation induced changes in gene expression.

    PubMed

    Stewart, J; Ko, Y-H; Kennedy, A R

    2007-06-01

    Ionizing radiation can produce adverse biological effects in astronauts during space travel. Of particular concern are the types of radiation from highly energetic, heavy, charged particles known as HZE particles. The aims of our studies are to characterize HZE particle radiation induced biological effects and evaluate the effects of L-selenomethionine (SeM) on these adverse biological effects. In this study, microarray technology was used to measure HZE radiation induced changes in gene expression, as well as to evaluate modulation of these changes by SeM. Human thyroid epithelial cells (HTori-3) were irradiated (1 GeV/n iron ions) in the presence or in the absence of 5 microM SeM. At 6 h post-irradiation, all cells were harvested for RNA isolation. Gene Chip U133Av2 from Affymetrix was used for the analysis of gene expression, and ANOVA and EASE were used for a determination of the genes and biological processes whose differential expression is statistically significant. Results of this microarray study indicate that exposure to small doses of radiation from HZE particles, 10 and 20 cGy from iron ions, induces statistically significant differential expression of 196 and 610 genes, respectively. In the presence of SeM, differential expression of 77 out of 196 genes (exposure to 10 cGy) and 336 out of 610 genes (exposure to 20 cGy) is abolished. In the presence or in the absence of SeM, radiation from HZE particles induces differential expression of genes whose products have roles in the induction of G1/S arrest during the mitotic cell cycle, as well as heat shock proteins. Some of the genes, whose expressions were affected by radiation from HZE particles and were unchanged in irradiated cells treated with SeM, have been shown to have altered expression levels in cancer cells. The conclusions of this report are that radiation from HZE particles can induce differential expression of many genes, some of which are known to play roles in the same processes that have

  8. Protective effects of L-selenomethionine on space radiation induced changes in gene expression.

    PubMed

    Stewart, J; Ko, Y-H; Kennedy, A R

    2007-06-01

    Ionizing radiation can produce adverse biological effects in astronauts during space travel. Of particular concern are the types of radiation from highly energetic, heavy, charged particles known as HZE particles. The aims of our studies are to characterize HZE particle radiation induced biological effects and evaluate the effects of L-selenomethionine (SeM) on these adverse biological effects. In this study, microarray technology was used to measure HZE radiation induced changes in gene expression, as well as to evaluate modulation of these changes by SeM. Human thyroid epithelial cells (HTori-3) were irradiated (1 GeV/n iron ions) in the presence or in the absence of 5 microM SeM. At 6 h post-irradiation, all cells were harvested for RNA isolation. Gene Chip U133Av2 from Affymetrix was used for the analysis of gene expression, and ANOVA and EASE were used for a determination of the genes and biological processes whose differential expression is statistically significant. Results of this microarray study indicate that exposure to small doses of radiation from HZE particles, 10 and 20 cGy from iron ions, induces statistically significant differential expression of 196 and 610 genes, respectively. In the presence of SeM, differential expression of 77 out of 196 genes (exposure to 10 cGy) and 336 out of 610 genes (exposure to 20 cGy) is abolished. In the presence or in the absence of SeM, radiation from HZE particles induces differential expression of genes whose products have roles in the induction of G1/S arrest during the mitotic cell cycle, as well as heat shock proteins. Some of the genes, whose expressions were affected by radiation from HZE particles and were unchanged in irradiated cells treated with SeM, have been shown to have altered expression levels in cancer cells. The conclusions of this report are that radiation from HZE particles can induce differential expression of many genes, some of which are known to play roles in the same processes that have

  9. Galahad: a web server for drug effect analysis from gene expression.

    PubMed

    Laenen, Griet; Ardeshirdavani, Amin; Moreau, Yves; Thorrez, Lieven

    2015-07-01

    Galahad (https://galahad.esat.kuleuven.be) is a web-based application for analysis of drug effects. It provides an intuitive interface to be used by anybody interested in leveraging microarray data to gain insights into the pharmacological effects of a drug, mainly identification of candidate targets, elucidation of mode of action and understanding of off-target effects. The core of Galahad is a network-based analysis method of gene expression. As an input, Galahad takes raw Affymetrix human microarray data from treatment versus control experiments and provides quality control and data exploration tools, as well as computation of differential expression. Alternatively, differential expression values can be uploaded directly. Using these differential expression values, drug target prioritization and both pathway and disease enrichment can be calculated and visualized. Drug target prioritization is based on the integration of the gene expression data with a functional protein association network. The web site is free and open to all and there is no login requirement. PMID:25940630

  10. Galahad: a web server for drug effect analysis from gene expression.

    PubMed

    Laenen, Griet; Ardeshirdavani, Amin; Moreau, Yves; Thorrez, Lieven

    2015-07-01

    Galahad (https://galahad.esat.kuleuven.be) is a web-based application for analysis of drug effects. It provides an intuitive interface to be used by anybody interested in leveraging microarray data to gain insights into the pharmacological effects of a drug, mainly identification of candidate targets, elucidation of mode of action and understanding of off-target effects. The core of Galahad is a network-based analysis method of gene expression. As an input, Galahad takes raw Affymetrix human microarray data from treatment versus control experiments and provides quality control and data exploration tools, as well as computation of differential expression. Alternatively, differential expression values can be uploaded directly. Using these differential expression values, drug target prioritization and both pathway and disease enrichment can be calculated and visualized. Drug target prioritization is based on the integration of the gene expression data with a functional protein association network. The web site is free and open to all and there is no login requirement.

  11. Optimization of gene expression microarray protocol for formalin-fixed paraffin-embedded tissues.

    PubMed

    Belder, Nevin; Coşkun, Öznur; Erdoğan, Beyza Doğanay; Savaş, Berna; Ensari, Arzu; Özdağ, Hilal

    2016-03-01

    Formalin-fixed paraffin-embedded (FFPE) tissue is a widely available clinical specimen for retrospective studies. The possibility of long-term clinical follow-up of FFPE samples makes them a valuable source to evaluate links between molecular and clinical information. Working with FFPE samples in the molecular research area, especially using high-throughput molecular techniques such as microarray gene expression profiling, has come into prominence. Because of the harmful effects of formalin fixation process such as degradation of nucleic acids, cross-linking with proteins, and chemical modifications on DNA and RNA, there are some limitations in gene expression profiling studies using FFPE samples. To date many studies have been conducted to evaluate gene expression profiling using microarrays (Thomas et al., Thomas et al. (2013) [1]; Scicchitano et al., Scicchitano et al. (2006) [2]; Frank et al., Frank et al. (2007) [3]; Fedorowicz et al., Fedorowicz et al. (2009) [4]). However, there is still no generally accepted, efficient and standardized procedure for microarray analysis of FFPE samples. This paper describes the microarray data presented in our recently accepted to be published article showing a standard protocol from deparaffinization of FFPE tissue sections and RNA extraction to microarray gene expression analysis. Here we represent our data in detail, deposited in the gene expression omnibus (GEO) database with the accession number GSE73883. Four combinations of two different cRNA/cDNA preparation and labeling protocols with two different array platforms (Affymetrix Human Genome U133 Plus 2.0 and U133_X3P) were evaluated to determine which combination gives the best percentage of present call. The study presents a dataset for comparative analysis which has a potential in terms of providing a robust protocol for gene expression profiling with FFPE tissue samples. PMID:26981433

  12. Levonorgestrel enhances spermatogenesis suppression by testosterone with greater alteration in testicular gene expression in men.

    PubMed

    Lue, YanHe; Wang, Christina; Cui, YuGui; Wang, XingHai; Sha, JiaHao; Zhou, ZuoMin; Xu, Jun; Wang, Charles; Hikim, Amiya P Sinha; Swerdloff, Ronald S

    2009-03-01

    Prior studies have demonstrated that combined treatment of testosterone with a progestin induces a more rapid and greater suppression of spermatogenesis than testosterone treatment alone. We hypothesized that the suppressive effects of the combination of testosterone undecanoate (TU) injections plus oral levonorgestrel (LNG) on spermatogenesis may be mediated through a greater perturbation of testicular gene expression than TU alone. To test this hypothesis, we performed open testicular biopsy on 12 different adult healthy subjects: 1) four healthy men as controls; 2) four men 2 wk after TU treatment; and 3) four men 2 wk after TU + LNG administration. RNA isolated from biopsies was used for DNA microarray using the Affymetrix Human Genome U133 Plus 2.0 oligonucleotide microarrays. Gene expression with >or=2-fold changes (P < 0.05) compared with control was analyzed using the National Institutes of Health Database for Annotation, Visualization, and Integrated Discovery 2008 resource. The TU treatment altered the gene expression in 109 transcripts, whereas TU + LNG altered the gene expression in 207 transcripts compared with control. Both TU and TU + LNG administration suppressed gene expression of insulin-like 3; cytochrome P450, family 17, subfamily A1 in Leydig cells; and inhibin alpha in Sertoli cells; they increased proapoptotic transcripts BCL2-like 14, insulin-like growth factor-binding protein 3; and they decreased X-linked inhibitor of apoptosis protein. In comparison with TU treatment alone, TU + LNG treatment upregulated insulin-like 6 and relaxin 1, and downregulated RNA-binding protein transcripts. We conclude that TU + LNG administration induces more changes in testicular gene expression than TU alone. This exploratory study provided a novel and valuable database to study the mechanisms of action of hormonal regulation of spermatogenesis in men and identified testicular-specific molecules that may serve as potential targets for male contraceptive

  13. Optimization of gene expression microarray protocol for formalin-fixed paraffin-embedded tissues.

    PubMed

    Belder, Nevin; Coşkun, Öznur; Erdoğan, Beyza Doğanay; Savaş, Berna; Ensari, Arzu; Özdağ, Hilal

    2016-03-01

    Formalin-fixed paraffin-embedded (FFPE) tissue is a widely available clinical specimen for retrospective studies. The possibility of long-term clinical follow-up of FFPE samples makes them a valuable source to evaluate links between molecular and clinical information. Working with FFPE samples in the molecular research area, especially using high-throughput molecular techniques such as microarray gene expression profiling, has come into prominence. Because of the harmful effects of formalin fixation process such as degradation of nucleic acids, cross-linking with proteins, and chemical modifications on DNA and RNA, there are some limitations in gene expression profiling studies using FFPE samples. To date many studies have been conducted to evaluate gene expression profiling using microarrays (Thomas et al., Thomas et al. (2013) [1]; Scicchitano et al., Scicchitano et al. (2006) [2]; Frank et al., Frank et al. (2007) [3]; Fedorowicz et al., Fedorowicz et al. (2009) [4]). However, there is still no generally accepted, efficient and standardized procedure for microarray analysis of FFPE samples. This paper describes the microarray data presented in our recently accepted to be published article showing a standard protocol from deparaffinization of FFPE tissue sections and RNA extraction to microarray gene expression analysis. Here we represent our data in detail, deposited in the gene expression omnibus (GEO) database with the accession number GSE73883. Four combinations of two different cRNA/cDNA preparation and labeling protocols with two different array platforms (Affymetrix Human Genome U133 Plus 2.0 and U133_X3P) were evaluated to determine which combination gives the best percentage of present call. The study presents a dataset for comparative analysis which has a potential in terms of providing a robust protocol for gene expression profiling with FFPE tissue samples.

  14. Rapid and dynamic alterations of gene expression profiles of adult porcine bone marrow derived stem cell in response to hypoxia

    PubMed Central

    Wang, Suna; Zhou, Yifu; Seavey, Caleb N.; Singh, Avneesh K.; Xu, Xiuli; Hunt, Timothy; Hoyt, Robert F.; Horvath, Keith A.

    2013-01-01

    This study sought to identify the gene expression patterns of porcine bone marrow-derived MSC in response to hypoxia and investigate novel specific hypoxic targets that may have a role in determining MSC proliferation/survival and differentiation. MSC from fifteen animals were incubated in 1% oxygen and 8% carbon dioxide for 6, 12 and 24 hours. RNA samples were isolated and assayed with Affymetrix porcine arrays and quantitative reverse transcription PCR. Significant gene expression levels among the four groups of normoxia, 6-, 12- and 24-hours hypoxia were identified. The pattern in the 12-hours hypoxia group was similar to that of 24-hours. Of 23,924 probes, 377 and 210 genes were regulated in the 6- and 24-hours hypoxia groups, respectively. Functional classification of the hypoxic regulated genes was mainly clustered in cell proliferation and response to stress. However, the major upregulated genes in the 6-hours group were activated in cell cycle phases; the genes in the 24-hours hypoxia were evenly separated into cell differentiation, apoptosis and cellular metabolic processes. Twenty-eight genes were upregulated in all hypoxia groups; these genes are considered as hypoxic targets. Our results identified a genome-wide hypoxia induced gene expression pattern in porcine MSC. This study provides a global view of molecular events in the cells during exposure to hypoxia and revealed a set of novel candidate hypoxic targets. PMID:20172499

  15. SAMP8 mice have altered hippocampal gene expression in long term potentiation, phosphatidylinositol signaling, and endocytosis pathways.

    PubMed

    Armbrecht, Harvey J; Siddiqui, Akbar M; Green, Michael; Farr, Susan A; Kumar, Vijaya B; Banks, William A; Patrick, Ping; Shah, Gul N; Morley, John E

    2014-01-01

    The senescence-accelerated mouse (SAMP8) strain exhibits decreased learning and memory and increased amyloid beta (Aβ) peptide accumulation at 12 months. To detect differences in gene expression in SAMP8 mice, we used a control mouse that was a 50% cross between SAMP8 and CD-1 mice and which showed no memory deficits (50% SAMs). We then compared gene expression in the hippocampus of 4- and 12-month-old SAMP8 and control mice using Affymetrix gene arrays. At 12 months, but not at 4 months, pathway analysis revealed significant differences in the long term potentiation (6 genes), phosphatidylinositol signaling (6 genes), and endocytosis (10 genes) pathways. The changes in long term potentiation included mitogen-activated protein kinase (MAPK) signaling (N-ras, cAMP responsive element binding protein [CREB], protein phosphatase inhibitor 1) and Ca-dependent signaling (inositol triphosphate [ITP] receptors 1 and 2 and phospholipase C). Changes in phosphatidylinositol signaling genes suggested altered signaling through phosphatidylinositol-3-kinase, and Western blotting revealed phosphorylation changes in serine/threonine protein kinase AKT and 70S6K. Changes in the endocytosis pathway involved genes related to clathrin-mediated endocytosis (dynamin and clathrin). Endocytosis is required for receptor recycling, is involved in Aβ metabolism, and is regulated by phosphatidylinositol signaling. In summary, these studies demonstrate altered gene expression in 3 SAMP8 hippocampal pathways associated with memory formation and consolidation. These pathways might provide new therapeutic targets in addition to targeting Aβ metabolism itself.

  16. Methods for monitoring multiple gene expression

    SciTech Connect

    Berka, Randy; Bachkirova, Elena; Rey, Michael

    2012-05-01

    The present invention relates to methods for monitoring differential expression of a plurality of genes in a first filamentous fungal cell relative to expression of the same genes in one or more second filamentous fungal cells using microarrays containing Trichoderma reesei ESTs or SSH clones, or a combination thereof. The present invention also relates to computer readable media and substrates containing such array features for monitoring expression of a plurality of genes in filamentous fungal cells.

  17. Methods for monitoring multiple gene expression

    SciTech Connect

    Berka, Randy; Bachkirova, Elena; Rey, Michael

    2008-06-01

    The present invention relates to methods for monitoring differential expression of a plurality of genes in a first filamentous fungal cell relative to expression of the same genes in one or more second filamentous fungal cells using microarrays containing Trichoderma reesei ESTs or SSH clones, or a combination thereof. The present invention also relates to computer readable media and substrates containing such array features for monitoring expression of a plurality of genes in filamentous fungal cells.

  18. Methods for monitoring multiple gene expression

    SciTech Connect

    Berka, Randy; Bachkirova, Elena; Rey, Michael

    2013-10-01

    The present invention relates to methods for monitoring differential expression of a plurality of genes in a first filamentous fungal cell relative to expression of the same genes in one or more second filamentous fungal cells using microarrays containing Trichoderma reesei ESTs or SSH clones, or a combination thereof. The present invention also relates to computer readable media and substrates containing such array features for monitoring expression of a plurality of genes in filamentous fungal cells.

  19. Gene Expression Profiling in Peripheral Blood Cells and Synovial Membranes of Patients with Psoriatic Arthritis

    PubMed Central

    Barbieri, Alessandro; Patuzzo, Giuseppe; Tinazzi, Elisa; Argentino, Giuseppe; Beri, Ruggero; Lunardi, Claudio; Puccetti, Antonio

    2015-01-01

    Background Psoriatic arthritis (PsA) is an inflammatory arthritis whose pathogenesis is poorly understood; it is characterized by bone erosions and new bone formation. The diagnosis of PsA is mainly clinical and diagnostic biomarkers are not yet available. The aim of this work was to clarify some aspects of the disease pathogenesis and to identify specific gene signatures in paired peripheral blood cells (PBC) and synovial biopsies of patients with PsA. Moreover, we tried to identify biomarkers that can be used in clinical practice. Methods PBC and synovial biopsies of 10 patients with PsA were used to study gene expression using Affymetrix arrays. The expression values were validated by Q-PCR, FACS analysis and by the detection of soluble mediators. Results Synovial biopsies of patients showed a modulation of approximately 200 genes when compared to the biopsies of healthy donors. Among the differentially expressed genes we observed the upregulation of Th17 related genes and of type I interferon (IFN) inducible genes. FACS analysis confirmed the Th17 polarization. Moreover, the synovial trascriptome shows gene clusters (bone remodeling, angiogenesis and inflammation) involved in the pathogenesis of PsA. Interestingly 90 genes are modulated in both compartments (PBC and synovium) suggesting that signature pathways in PBC mirror those of the inflamed synovium. Finally the osteoactivin gene was upregulared in both PBC and synovial biopsies and this finding was confirmed by the detection of high levels of osteoactivin in PsA sera but not in other inflammatory arthritides. Conclusions We describe the first analysis of the trancriptome in paired synovial tissue and PBC of patients with PsA. This study strengthens the hypothesis that PsA is of autoimmune origin since the coactivity of IFN and Th17 pathways is typical of autoimmunity. Finally these findings have allowed the identification of a possible disease biomarker, osteoactivin, easily detectable in PsA serum. PMID

  20. Gene expression patterns related to osteogenic differentiation of bone marrow-derived mesenchymal stem cells during ex vivo expansion.

    PubMed

    Granchi, Donatella; Ochoa, Gorka; Leonardi, Elisa; Devescovi, Valentina; Baglìo, Serena Rubina; Osaba, Lourdes; Baldini, Nicola; Ciapetti, Gabriela

    2010-06-01

    Bone marrow is commonly used as a source of adult multipotent mesenchymal stem cells (MSCs), defined for their ability to differentiate in vitro into multiple lineages. The ex vivo-expanded MSCs are currently being evaluated as a strategy for the restoration of function in damaged skeletal tissue, both in cell therapy and tissue engineering applications. The aim of this study was to define gene expression patterns underlying the differentiation of MSCs into mature osteoblasts during the expansion in vitro, and to explore a variety of cell functions that cannot be easily evaluated using morphological, cytochemical, and biochemical assays. Cell cultures were obtained from bone marrow samples of six individuals undergoing total hip replacement, and a large-scale transcriptome analysis, using Affymetrix HG-U133A Plus 2.0 array (Affymetrix((R)), Santa Clara, CA), was performed at the occurrence of specific events, including the appearance of MSC surface markers, formation of colonies, and deposition of mineral nodules. We focused our attention on 213 differentially upregulated genes, some belonging to well-known pathways and some having one or more Gene Ontology annotations related to bone cell biology, including angiogenesis, bone-related genes, cell communication, development and morphogenesis, transforming growth factor-beta signaling, and Wnt signaling. Twenty-nine genes, whose role in bone cell pathophysiology has not been described yet, were found. In conclusion, gene expression patterns that characterize the early, intermediate, and late phases of the osteogenic differentiation process of ex vivo-expanded MSCs were defined. These signatures represent a useful tool to monitor the osteogenic process, and to analyze a broad spectrum of functions of MSCs cultured on scaffolds, especially when the constructs are conceived for releasing growth factors or other signals to promote bone regeneration.

  1. Effect of transgenes on global gene expression in soybean is within the natural range of variation of conventional cultivars.

    PubMed

    Cheng, K C; Beaulieu, J; Iquira, E; Belzile, F J; Fortin, M G; Strömvik, M V

    2008-05-14

    Current safety assessment for novel crops, including transgenic crops, uses a targeted approach, which relies on compositional analysis. The possibility that transgene expression could lead to unintended effects remains a debated issue. This study used transcriptome profiling as a nontargeted approach to evaluate overall molecular changes in transgenic soybean cultivars. Global gene expression was measured in the first trifoliate leaves of two transgenic and three conventional soybean cultivars using the soybean Affymetrix GeneChip. It was found that gene expression differs more between the two conventional cultivars than between the transgenics and their closest conventional cultivar investigated and that the magnitudes of differences measured in gene expression and genotype (determined by SSR analysis) do not necessarily correlate. A MySQL database coupled with a CGI Web interface was developed to store and present the results ( http://soyxpress.agrenv.mcgill.ca/). By integrating the microarray data with gene annotations and other soybean data, a comprehensive view of differences in gene expression is explored between cultivars.

  2. Microarray profiling of gene expression patterns in glomerular cells of astaxanthin-treated diabetic mice: a nutrigenomic approach.

    PubMed

    Naito, Yuji; Uchiyama, Kazuhiko; Mizushima, Katsura; Kuroda, Masaaki; Akagiri, Satomi; Takagi, Tomohisa; Handa, Osamu; Kokura, Satoshi; Yoshida, Norimasa; Ichikawa, Hiroshi; Takahashi, Jiro; Yoshikawa, Toshikazu

    2006-10-01

    We have demonstrated that astaxanthin reduces glomerular oxidative stress as well as inhibits the increase in urinary albumin in diabetic db/db mice. The aim of the present study was to determine the gene expression patterns in the glomerular cells of the diabetic mouse kidney, and to investigate the effects of astaxanthin on the expression of these genes using a high-density DNA microarray. The diet administered to the astaxanthin-supplementation group was prepared by mixing a control powder with astaxanthin at a concentration of 0.02%. Glomerular cells were obtained from the kidneys of mice by laser capture microdissection. Preparation of cRNA and target hybridization were performed according to the Affymetrix GeneChip eukaryotic small sample target labeling assay protocol. The gene expression profile was evaluated by the mouse expression set 430A GeneChip. Array data analysis was carried out using Affymetrix GeneChip operating and Ingenuity Pathway analysis software. Comparison between diabetic db/db and non-diabetic db/m mice revealed that 779 probes (3.1%) were significantly affected, i.e. 550 probes were up-regulated, and 229 probes were down-regulated, both at levels of >/=1.5-fold in the diabetic mice. Ingenuity signal analysis of 550 up-regulated probes revealed the mitochondrial oxidative phosphorylation pathway as the most significantly affected caronical pathway. The affected genes were associated with complexes I, III, and IV located on the mitochondrial inner membrane, and the expression levels of these genes were decreased in mice treated with astaxanthin as compared to the levels in the control mice. In addition, the expression of many genes associated with oxidative stress, collagen synthesis, and transforming growth factor-beta signaling was enhanced in the diabetic mice, and this enhancement was slightly inhibited in the astaxanthin-treated mice. In conclusion, this genome-wide nutrigenomics approach provided insight into genes and putative

  3. Dengue Virus Induces Novel Changes in Gene Expression of Human Umbilical Vein Endothelial Cells

    PubMed Central

    Warke, Rajas V.; Xhaja, Kris; Martin, Katherine J.; Fournier, Marcia F.; Shaw, Sunil K.; Brizuela, Nathaly; de Bosch, Norma; Lapointe, David; Ennis, Francis A.; Rothman, Alan L.; Bosch, Irene

    2003-01-01

    Endothelial cells are permissive to dengue virus (DV) infection in vitro, although their importance as targets of DV infection in vivo remains a subject of debate. To analyze the virus-host interaction, we studied the effect of DV infection on gene expression in human umbilical vein endothelial cells (HUVECs) by using differential display reverse transcription-PCR (DD-RTPCR), quantitative RT-PCR, and Affymetrix oligonucleotide microarrays. DD identified eight differentially expressed cDNAs, including inhibitor of apoptosis-1, 2′-5′ oligoadenylate synthetase (OAS), a 2′-5′ OAS-like (OASL) gene, galectin-9, myxovirus protein A (MxA), regulator of G-protein signaling, endothelial and smooth muscle cell-derived neuropilin-like protein, and phospholipid scramblase 1. Microarray analysis of 22,000 human genes confirmed these findings and identified an additional 269 genes that were induced and 126 that were repressed more than fourfold after DV infection. Broad functional responses that were activated included the stress, defense, immune, cell adhesion, wounding, inflammatory, and antiviral pathways. These changes in gene expression were seen after infection of HUVECs with either laboratory-adapted virus or with virus isolated directly from plasma of DV-infected patients. Tumor necrosis factor alpha, OASL, and MxA and h-IAP1 genes were induced within the first 8 to 12 h after infection, suggesting a direct effect of DV infection. These global analyses of DV effects on cellular gene expression identify potentially novel mechanisms involved in dengue disease manifestations such as hemostatic disturbance. PMID:14557666

  4. Rawcopy: Improved copy number analysis with Affymetrix arrays

    PubMed Central

    Mayrhofer, Markus; Viklund, Björn; Isaksson, Anders

    2016-01-01

    Microarray data is subject to noise and systematic variation that negatively affects the resolution of copy number analysis. We describe Rawcopy, an R package for processing of Affymetrix CytoScan HD, CytoScan 750k and SNP 6.0 microarray raw intensities (CEL files). Noise characteristics of a large number of reference samples are used to estimate log ratio and B-allele frequency for total and allele-specific copy number analysis. Rawcopy achieves better signal-to-noise ratio and higher proportion of validated alterations than commonly used free and proprietary alternatives. In addition, Rawcopy visualizes each microarray sample for assessment of technical quality, patient identity and genome-wide absolute copy number states. Software and instructions are available at http://rawcopy.org. PMID:27796336

  5. Profiling Gene Expression in Germinating Brassica Roots.

    PubMed

    Park, Myoung Ryoul; Wang, Yi-Hong; Hasenstein, Karl H

    2014-01-01

    Based on previously developed solid-phase gene extraction (SPGE) we examined the mRNA profile in primary roots of Brassica rapa seedlings for highly expressed genes like ACT7 (actin7), TUB (tubulin1), UBQ (ubiquitin), and low expressed GLK (glucokinase) during the first day post-germination. The assessment was based on the mRNA load of the SPGE probe of about 2.1 ng. The number of copies of the investigated genes changed spatially along the length of primary roots. The expression level of all genes differed significantly at each sample position. Among the examined genes ACT7 expression was most even along the root. UBQ was highest at the tip and root-shoot junction (RS). TUB and GLK showed a basipetal gradient. The temporal expression of UBQ was highest in the MZ 9 h after primary root emergence and higher than at any other sample position. Expressions of GLK in EZ and RS increased gradually over time. SPGE extraction is the result of oligo-dT and oligo-dA hybridization and the results illustrate that SPGE can be used for gene expression profiling at high spatial and temporal resolution. SPGE needles can be used within two weeks when stored at 4 °C. Our data indicate that gene expression studies that are based on the entire root miss important differences in gene expression that SPGE is able to resolve for example growth adjustments during gravitropism.

  6. Gene expression profiles in the rat streptococcal cell wall-induced arthritis model identified using microarray analysis.

    PubMed

    Rioja, Inmaculada; Clayton, Chris L; Graham, Simon J; Life, Paul F; Dickson, Marion C

    2005-01-01

    Experimental arthritis models are considered valuable tools for delineating mechanisms of inflammation and autoimmune phenomena. Use of microarray-based methods represents a new and challenging approach that allows molecular dissection of complex autoimmune diseases such as arthritis. In order to characterize the temporal gene expression profile in joints from the reactivation model of streptococcal cell wall (SCW)-induced arthritis in Lewis (LEW/N) rats, total RNA was extracted from ankle joints from naive, SCW injected, or phosphate buffered saline injected animals (time course study) and gene expression was analyzed using Affymetrix oligonucleotide microarray technology (RAE230A). After normalization and statistical analysis of data, 631 differentially expressed genes were sorted into clusters based on their levels and kinetics of expression using Spotfire profile search and K-mean cluster analysis. Microarray-based data for a subset of genes were validated using real-time PCR TaqMan analysis. Analysis of the microarray data identified 631 genes (441 upregulated and 190 downregulated) that were differentially expressed (Delta > 1.8, P < 0.01), showing specific levels and patterns of gene expression. The genes exhibiting the highest fold increase in expression on days -13.8, -13, or 3 were involved in chemotaxis, inflammatory response, cell adhesion and extracellular matrix remodelling. Transcriptome analysis identified 10 upregulated genes (Delta > 5), which have not previously been associated with arthritis pathology and are located in genomic regions associated with autoimmune disease. The majority of the downregulated genes were associated with metabolism, transport and regulation of muscle development. In conclusion, the present study describes the temporal expression of multiple disease-associated genes with potential pathophysiological roles in the reactivation model of SCW-induced arthritis in Lewis (LEW/N) rat. These findings improve our understanding of

  7. Comparison of gene expression profiling between malignant and normal plasma cells with oligonucleotide arrays.

    PubMed

    De Vos, John; Thykjaer, Thomas; Tarte, Karin; Ensslen, Matthias; Raynaud, Pierre; Requirand, Guilhem; Pellet, Florence; Pantesco, Véronique; Rème, Thierry; Jourdan, Michel; Rossi, Jean-François; Ørntoft, Torben; Klein, Bernard

    2002-10-01

    The DNA microarray technology enables the identification of the large number of genes involved in the complex deregulation of cell homeostasis taking place in cancer. Using Affymetrix microarrays, we have compared the gene expression profiles of highly purified malignant plasma cells from nine patients with multiple myeloma (MM) and eight myeloma cell lines to those of highly purified nonmalignant plasma cells (eight samples) obtained by in vitro differentiation of peripheral blood B cells. Two unsupervised clustering algorithms classified these 25 samples into two distinct clusters: a malignant plasma cell cluster and a normal plasma cell cluster. Two hundred and fifty genes were significantly up-regulated and 159 down-regulated in malignant plasma samples compared to normal plasma samples. For some of these genes, an overexpression or downregulation of the encoded protein was confirmed (cyclin D1, c-myc, BMI-1, cystatin c, SPARC, RB). Two genes overexpressed in myeloma cells (ABL and cystathionine beta synthase) code for enzymes that could be a therapeutic target with specific drugs. These data provide a new insight into the understanding of myeloma disease and prefigure that the development of DNA microarray could help to develop an 'à la carte' treatment in cancer disease.

  8. Gene expression profiling in the lung tissue of cynomolgus monkeys in response to repeated exposure to welding fumes.

    PubMed

    Heo, Jeong-Doo; Oh, Jung-Hwa; Lee, Kyuhong; Kim, Choong Yong; Song, Chang-Woo; Yoon, Seokjoo; Han, Jin Soo; Yu, Il Je

    2010-03-01

    Many in the welding industry suffer from bronchitis, lung function changes, metal fume fever, and diseases related to respiratory damage. These phenomena are associated with welding fumes; however, the mechanism behind these findings remains to be elucidated. In this study, the lungs of cynomolgus monkeys were exposed to MMA-SS welding fumes for 229 days and allowed to recover for 153 days. After the exposure and recovery period, gene expression profiles were investigated using the Affymetrix GeneChip Human U133 plus 2.0. In total, it was confirmed that 1,116 genes were up-or downregulated (over 2-fold changes, P\\0.01) for the T1 (31.4 ± 2.8 mg/m3) and T2 (62.5 ± 2.7 mg/m3) dose groups. Differentially expressed genes in the exposure and recovery groups were analyzed, based on hierarchical clustering, and were imported into Ingenuity Pathways Analysis to analyze the biological and toxicological functions. Functional analysis identified genes involved in immunological disease in both groups. Additionally, differentially expressed genes in common between monkeys and rats following welding fume exposure were compared using microarray data, and the gene expression of selected genes was verified by real-time PCR. Genes such as CHI3L1, RARRES1, and CTSB were up-regulated and genes such as CYP26B1, ID4, and NRGN were down-regulated in both monkeys and rats following welding fume exposure. This is the first comprehensive gene expression profiling conducted for welding fume exposure in monkeys, and these expressed genes are expected to be useful in helping to understand transcriptional changes in monkey lungs after welding fume exposure.

  9. Gene Expression Patterns in Ovarian Carcinomas

    PubMed Central

    Schaner, Marci E.; Ross, Douglas T.; Ciaravino, Giuseppe; Sørlie, Therese; Troyanskaya, Olga; Diehn, Maximilian; Wang, Yan C.; Duran, George E.; Sikic, Thomas L.; Caldeira, Sandra; Skomedal, Hanne; Tu, I-Ping; Hernandez-Boussard, Tina; Johnson, Steven W.; O'Dwyer, Peter J.; Fero, Michael J.; Kristensen, Gunnar B.; Børresen-Dale, Anne-Lise; Hastie, Trevor; Tibshirani, Robert; van de Rijn, Matt; Teng, Nelson N.; Longacre, Teri A.; Botstein, David; Brown, Patrick O.; Sikic, Branimir I.

    2003-01-01

    We used DNA microarrays to characterize the global gene expression patterns in surface epithelial cancers of the ovary. We identified groups of genes that distinguished the clear cell subtype from other ovarian carcinomas, grade I and II from grade III serous papillary carcinomas, and ovarian from breast carcinomas. Six clear cell carcinomas were distinguished from 36 other ovarian carcinomas (predominantly serous papillary) based on their gene expression patterns. The differences may yield insights into the worse prognosis and therapeutic resistance associated with clear cell carcinomas. A comparison of the gene expression patterns in the ovarian cancers to published data of gene expression in breast cancers revealed a large number of differentially expressed genes. We identified a group of 62 genes that correctly classified all 125 breast and ovarian cancer specimens. Among the best discriminators more highly expressed in the ovarian carcinomas were PAX8 (paired box gene 8), mesothelin, and ephrin-B1 (EFNB1). Although estrogen receptor was expressed in both the ovarian and breast cancers, genes that are coregulated with the estrogen receptor in breast cancers, including GATA-3, LIV-1, and X-box binding protein 1, did not show a similar pattern of coexpression in the ovarian cancers. PMID:12960427

  10. Gearbox gene expression and growth rate.

    PubMed

    Aldea, M; Garrido, T; Tormo, A

    1993-07-01

    Regulation of gene expression in prokaryotic cells usually takes place at the level of transcription initiation. Different forms of RNA polymerase recognizing specific promoters are engaged in the control of many prokaryotic regulons. This also seems to be the case for some Escherichia coli genes that are induced at low growth rates and by nutrient starvation. Their gene products are synthesized at levels inversely proportional to growth rate, and this mode of regulation has been termed gearbox gene expression. This kind of growth-rate modulation is exerted by specific transcriptional initiation signals, the gearbox promoters, and some of them depend on a putative new σ factor (RpoS). Gearbox promoters drive expression of morphogenetic and cell division genes at constant levels per cell and cycle to meet the demands of cell division and septum formation. A mechanism is proposed that could sense the growth rate of the cell to alter gene expression by the action of specific σ factors.

  11. The gene expression signatures of melanoma progression

    PubMed Central

    Haqq, Christopher; Nosrati, Mehdi; Sudilovsky, Daniel; Crothers, Julia; Khodabakhsh, Daniel; Pulliam, Brian L.; Federman, Scot; Miller, James R.; Allen, Robert E.; Singer, Mark I.; Leong, Stanley P. L.; Ljung, Britt-Marie; Sagebiel, Richard W.; Kashani-Sabet, Mohammed

    2005-01-01

    Because of the paucity of available tissue, little information has previously been available regarding the gene expression profiles of primary melanomas. To understand the molecular basis of melanoma progression, we compared the gene expression profiles of a series of nevi, primary melanomas, and melanoma metastases. We found that metastatic melanomas exhibit two dichotomous patterns of gene expression, which unexpectedly reflect gene expression differences already apparent in comparing laser-capture microdissected radial and vertical phases of a large primary melanoma. Unsupervised hierarchical clustering accurately separated nevi and primary melanomas. Multiclass significance analysis of microarrays comparing normal skin, nevi, primary melanomas, and the two types of metastatic melanoma identified 2,602 transcripts that significantly correlated with sample class. These results suggest that melanoma pathogenesis can be understood as a series of distinct molecular events. The gene expression signatures identified here provide the basis for developing new diagnostics and targeting therapies for patients with malignant melanoma. PMID:15833814

  12. Gene expression profiling in primary mouse hepatocytes discriminates true from false-positive genotoxic compounds.

    PubMed

    Mathijs, K; Brauers, K J J; Jennen, D G J; Lizarraga, D; Kleinjans, J C S; van Delft, J H M

    2010-11-01

    Well-established in vitro methods for testing the genotoxic potency of chemicals--such as the Ames/Salmonella test, the mouse lymphoma assay, the micronucleus test and the chromosomal aberration test--show a high false-positive rate for predicting in vivo genotoxicity and carcinogenicity. Thus, there is a need for more reliable in vitro assays. We investigated whether gene expression profiling in metabolically competent primary mouse hepatocytes is capable of discriminating true genotoxic (GTX) compounds from false-positive genotoxic (FP-GTX) compounds. Sandwich-cultured primary hepatocytes from male C57Bl6 mice were treated for 24 and 48 h with five true GTX and five FP-GTX compounds. Whole genome gene expression modifications were analysed by means of Affymetrix mouse genome 430 2.0 microarrays. Filtered genes were used for hierarchical clustering and class prediction methods. Classifiers were generated by prediction analysis of microarray using a leave-one-compound-out method and selecting the genes that were common to the 10 training sets. For the training compounds, all but one were correctly classified. Validation of the classification model with five new compounds resulted in a 100% correct classification at 24 h and 80% at 48 h. The generated classifiers were mostly involved in metabolic and biosynthetic processes, immune responses and apoptosis. Applying genes whose expression change correlates with γH2AX foci, a measure for DNA damage, did not improve the classification. The present study shows that gene expression profiling in primary mouse hepatocytes is capable of discriminating between true GTX and FP-GTX compounds.

  13. Gene expression profiling of RNA extracted from FFPE tissues: NuGEN technologies' whole-transcriptome amplification system.

    PubMed

    Turner, Leah; Heath, Joe Don; Kurn, Nurith

    2011-01-01

    Gene expression profiling of RNA isolated from formalin fixed, paraffin-embedded (FFPE) tissue samples has been historically challenging. Yet FFPE samples are sought-after because of the in-depth retrospective records typically associated with them rendering these samples a valuable resource for translational medicine studies. Extensive degradation, chemical modifications, and cross-linking have made it difficult to isolate RNA of sufficient quality required for large-scale gene expression profiling studies. NuGEN Technologies' WT-Ovation™ FFPE System linearly amplifies RNA from FFPE samples through a robust and simple whole-transcriptome approach using as little as 50 ng total RNA isolated from FFPE samples. The amplified material may be labeled with validated kits and/or protocols from NuGEN for analysis on any of the major gene expression microarray platforms, including: Affymetrix, Agilent, and Illumina gene expression arrays. Results compare well with those obtained using RNA from fresh-frozen samples. RNA quality from FFPE samples varies significantly and neither sample age nor sample size analysis via gel electrophoresis or the Agilent Bioanalyzer system accurately predict materials suitable for amplification. Therefore, NuGEN has validated a correlative qPCR-based analytical method for the RNA derived from FFPE samples which effectively predicts array results. The NuGEN approach enables fast and successful analysis of samples previously thought to be too degraded for gene expression analysis.

  14. The Mouse Gene Expression Database (GXD)

    PubMed Central

    Ringwald, Martin; Eppig, Janan T.; Begley, Dale A.; Corradi, John P.; McCright, Ingeborg J.; Hayamizu, Terry F.; Hill, David P.; Kadin, James A.; Richardson, Joel E.

    2001-01-01

    The Gene Expression Database (GXD) is a community resource of gene expression information for the laboratory mouse. By combining the different types of expression data, GXD aims to provide increasingly complete information about the expression profiles of genes in different mouse strains and mutants, thus enabling valuable insights into the molecular networks that underlie normal development and disease. GXD is integrated with the Mouse Genome Database (MGD). Extensive interconnections with sequence databases and with databases from other species, and the development and use of shared controlled vocabularies extend GXD’s utility for the analysis of gene expression information. GXD is accessible through the Mouse Genome Informatics web site at http://www.informatic s.jax.org/ or directly at http://www.informatics.jax.org/me nus/expression_menu.shtml. PMID:11125060

  15. A RNA-Seq Analysis of the Rat Supraoptic Nucleus Transcriptome: Effects of Salt Loading on Gene Expression

    PubMed Central

    Salinas, Yasmmyn D.; Shi, YiJun; Greenwood, Michael; Hoe, See Ziau; Murphy, David; Gainer, Harold

    2015-01-01

    Magnocellular neurons (MCNs) in the hypothalamo-neurohypophysial system (HNS) are highly specialized to release large amounts of arginine vasopressin (Avp) or oxytocin (Oxt) into the blood stream and play critical roles in the regulation of body fluid homeostasis. The MCNs are osmosensory neurons and are excited by exposure to hypertonic solutions and inhibited by hypotonic solutions. The MCNs respond to systemic hypertonic and hypotonic stimulation with large changes in the expression of their Avp and Oxt genes, and microarray studies have shown that these osmotic perturbations also cause large changes in global gene expression in the HNS. In this paper, we examine gene expression in the rat supraoptic nucleus (SON) under normosmotic and chronic salt-loading SL) conditions by the first time using “new-generation”, RNA sequencing (RNA-Seq) methods. We reliably detect 9,709 genes as present in the SON by RNA-Seq, and 552 of these genes were changed in expression as a result of chronic SL. These genes reflect diverse functions, and 42 of these are involved in either transcriptional or translational processes. In addition, we compare the SON transcriptomes resolved by RNA-Seq methods with the SON transcriptomes determined by Affymetrix microarray methods in rats under the same osmotic conditions, and find that there are 6,466 genes present in the SON that are represented in both data sets, although 1,040 of the expressed genes were found only in the microarray data, and 2,762 of the expressed genes are selectively found in the RNA-Seq data and not the microarray data. These data provide the research community a comprehensive view of the transcriptome in the SON under normosmotic conditions and the changes in specific gene expression evoked by salt loading. PMID:25897513

  16. A RNA-Seq Analysis of the Rat Supraoptic Nucleus Transcriptome: Effects of Salt Loading on Gene Expression.

    PubMed

    Johnson, Kory R; Hindmarch, C C T; Salinas, Yasmmyn D; Shi, YiJun; Greenwood, Michael; Hoe, See Ziau; Murphy, David; Gainer, Harold

    2015-01-01

    Magnocellular neurons (MCNs) in the hypothalamo-neurohypophysial system (HNS) are highly specialized to release large amounts of arginine vasopressin (Avp) or oxytocin (Oxt) into the blood stream and play critical roles in the regulation of body fluid homeostasis. The MCNs are osmosensory neurons and are excited by exposure to hypertonic solutions and inhibited by hypotonic solutions. The MCNs respond to systemic hypertonic and hypotonic stimulation with large changes in the expression of their Avp and Oxt genes, and microarray studies have shown that these osmotic perturbations also cause large changes in global gene expression in the HNS. In this paper, we examine gene expression in the rat supraoptic nucleus (SON) under normosmotic and chronic salt-loading SL) conditions by the first time using "new-generation", RNA sequencing (RNA-Seq) methods. We reliably detect 9,709 genes as present in the SON by RNA-Seq, and 552 of these genes were changed in expression as a result of chronic SL. These genes reflect diverse functions, and 42 of these are involved in either transcriptional or translational processes. In addition, we compare the SON transcriptomes resolved by RNA-Seq methods with the SON transcriptomes determined by Affymetrix microarray methods in rats under the same osmotic conditions, and find that there are 6,466 genes present in the SON that are represented in both data sets, although 1,040 of the expressed genes were found only in the microarray data, and 2,762 of the expressed genes are selectively found in the RNA-Seq data and not the microarray data. These data provide the research community a comprehensive view of the transcriptome in the SON under normosmotic conditions and the changes in specific gene expression evoked by salt loading.

  17. Photosynthetic gene expression in higher plants.

    PubMed

    Berry, James O; Yerramsetty, Pradeep; Zielinski, Amy M; Mure, Christopher M

    2013-11-01

    Within the chloroplasts of higher plants and algae, photosynthesis converts light into biological energy, fueling the assimilation of atmospheric carbon dioxide into biologically useful molecules. Two major steps, photosynthetic electron transport and the Calvin-Benson cycle, require many gene products encoded from chloroplast as well as nuclear genomes. The expression of genes in both cellular compartments is highly dynamic and influenced by a diverse range of factors. Light is the primary environmental determinant of photosynthetic gene expression. Working through photoreceptors such as phytochrome, light regulates photosynthetic genes at transcriptional and posttranscriptional levels. Other processes that affect photosynthetic gene expression include photosynthetic activity, development, and biotic and abiotic stress. Anterograde (from nucleus to chloroplast) and retrograde (from chloroplast to nucleus) signaling insures the highly coordinated expression of the many photosynthetic genes between these different compartments. Anterograde signaling incorporates nuclear-encoded transcriptional and posttranscriptional regulators, such as sigma factors and RNA-binding proteins, respectively. Retrograde signaling utilizes photosynthetic processes such as photosynthetic electron transport and redox signaling to influence the expression of photosynthetic genes in the nucleus. The basic C3 photosynthetic pathway serves as the default form used by most of the plant species on earth. High temperature and water stress associated with arid environments have led to the development of specialized C4 and CAM photosynthesis, which evolved as modifications of the basic default expression program. The goal of this article is to explain and summarize the many gene expression and regulatory processes that work together to support photosynthetic function in plants.

  18. SEGEL: A Web Server for Visualization of Smoking Effects on Human Lung Gene Expression.

    PubMed

    Xu, Yan; Hu, Brian; Alnajm, Sammy S; Lu, Yin; Huang, Yangxin; Allen-Gipson, Diane; Cheng, Feng

    2015-01-01

    Cigarette smoking is a major cause of death worldwide resulting in over six million deaths per year. Cigarette smoke contains complex mixtures of chemicals that are harmful to nearly all organs of the human body, especially the lungs. Cigarette smoking is considered the major risk factor for many lung diseases, particularly chronic obstructive pulmonary diseases (COPD) and lung cancer. However, the underlying molecular mechanisms of smoking-induced lung injury associated with these lung diseases still remain largely unknown. Expression microarray techniques have been widely applied to detect the effects of smoking on gene expression in different human cells in the lungs. These projects have provided a lot of useful information for researchers to understand the potential molecular mechanism(s) of smoke-induced pathogenesis. However, a user-friendly web server that would allow scientists to fast query these data sets and compare the smoking effects on gene expression across different cells had not yet been established. For that reason, we have integrated eight public expression microarray data sets from trachea epithelial cells, large airway epithelial cells, small airway epithelial cells, and alveolar macrophage into an online web server called SEGEL (Smoking Effects on Gene Expression of Lung). Users can query gene expression patterns across these cells from smokers and nonsmokers by gene symbols, and find the effects of smoking on the gene expression of lungs from this web server. Sex difference in response to smoking is also shown. The relationship between the gene expression and cigarette smoking consumption were calculated and are shown in the server. The current version of SEGEL web server contains 42,400 annotated gene probe sets represented on the Affymetrix Human Genome U133 Plus 2.0 platform. SEGEL will be an invaluable resource for researchers interested in the effects of smoking on gene expression in the lungs. The server also provides useful information

  19. Gene Expression Noise, Fitness Landscapes, and Evolution

    NASA Astrophysics Data System (ADS)

    Charlebois, Daniel

    The stochastic (or noisy) process of gene expression can have fitness consequences for living organisms. For example, gene expression noise facilitates the development of drug resistance by increasing the time scale at which beneficial phenotypic states can be maintained. The present work investigates the relationship between gene expression noise and the fitness landscape. By incorporating the costs and benefits of gene expression, we track how the fluctuation magnitude and timescale of expression noise evolve in simulations of cell populations under stress. We find that properties of expression noise evolve to maximize fitness on the fitness landscape, and that low levels of expression noise emerge when the fitness benefits of gene expression exceed the fitness costs (and that high levels of noise emerge when the costs of expression exceed the benefits). The findings from our theoretical/computational work offer new hypotheses on the development of drug resistance, some of which are now being investigated in evolution experiments in our laboratory using well-characterized synthetic gene regulatory networks in budding yeast. Nserc Postdoctoral Fellowship (Grant No. PDF-453977-2014).

  20. Time course differential gene expression in response to porcine circovirus type 2 subclinical infection

    PubMed Central

    Tomás, Anna; Fernandes, Lana T.; Sánchez, Armand; Segalés, Joaquim

    2009-01-01

    This study was aimed at characterizing the potential differences in gene expression in piglets inoculated with Porcine circovirus type 2 (PCV2), the essential causative agent of postweaning multisystemic wasting syndrome. Seven-day-old caesarean-derived, colostrum-deprived piglets were distributed into two groups: control (n = 8) and pigs inoculated with 105.2 TCID50 of the Burgos PCV2 isolate (n = 16). One control and three inoculated pigs were necropsied on days 1, 2, 5, and 8 post-infection (p.i.). The remaining pigs (four of each group) were sequentially bled on days 0, 7, 14, 21, and 29 p.i. (necropsy). Total RNA from the mediastinal lymph node (MLN) and lysed whole blood (LWB) samples were hybridized to Affymetrix Porcine GeneChip®. Forty-three probes were differentially expressed (DE) in MLN samples (FDR < 0.1, fold change > 2) and were distributed into three clusters: globally down-regulated genes, and up-regulated genes at early (first week p.i.) and late (day 29 p.i.) stages of infection. In LWB samples, maximal differences were observed at day 7 p.i., with 54 probes DE between control and inoculated pigs. Main Gene Ontology biological processes assigned to up-regulated genes were related to the immune response. Six common genes were found in both types of samples, all of which belonged to the interferon signaling antiviral effector pathway. Down-regulated genes were mainly related to cell adhesion and migration in MLN, and cellular organization and biogenesis in LWB. Microarray results were validated by quantitative real-time PCR. This study provides, for the first time, the characterization of the early and late molecular events taking place in response to a subclinical PCV2 infection. PMID:19825344

  1. Intraflagellar Transport Gene Expression Associated with Short Cilia in Smoking and COPD

    PubMed Central

    Hessel, Justina; Heldrich, Jonna; Fuller, Jennifer; Staudt, Michelle R.; Radisch, Sharon; Hollmann, Charleen; Harvey, Ben-Gary; Kaner, Robert J.; Salit, Jacqueline; Yee-Levin, Jenny; Sridhar, Sriram; Pillai, Sreekumar; Hilton, Holly; Wolff, Gerhard; Bitter, Hans; Visvanathan, Sudha; Fine, Jay; Stevenson, Christopher S.; Crystal, Ronald G.; Tilley, Ann E.

    2014-01-01

    Smoking and COPD are associated with decreased mucociliary clearance, and healthy smokers have shorter cilia in the large airway than nonsmokers. We hypothesized that changes in cilia length are consistent throughout the airway, and we further hypothesized that smokers with COPD have shorter cilia than healthy smokers. Because intraflagellar transport (IFT) is the process by which cilia of normal length are produced and maintained, and alterations in IFT lead to short cilia in model organisms, we also hypothesized that smoking induces changes in the expression of IFT-related genes in the airway epithelium of smokers and smokers with COPD. To assess these hypotheses, airway epithelium was obtained via bronchoscopic brushing. Cilia length was assessed by measuring 100 cilia (10 cilia on each of 10 cells) per subject and Affymetrix microarrays were used to evaluate IFT gene expression in nonsmokers and healthy smokers in 2 independent data sets from large and small airway as well as in COPD smokers in a data set from the small airway. In the large and small airway epithelium, cilia were significantly shorter in healthy smokers than nonsmokers, and significantly shorter in COPD smokers than in both healthy smokers and nonsmokers. The gene expression data confirmed that a set of 8 IFT genes were down-regulated in smokers in both data sets; however, no differences were seen in COPD smokers compared to healthy smokers. These results support the concept that loss of cilia length contributes to defective mucociliary clearance in COPD, and that smoking-induced changes in expression of IFT genes may be one mechanism of abnormally short cilia in smokers. Strategies to normalize cilia length may be an important avenue for novel COPD therapies. PMID:24465567

  2. Gene expression correlates of unexplained fatigue.

    PubMed

    Whistler, Toni; Taylor, Renee; Craddock, R Cameron; Broderick, Gordon; Klimas, Nancy; Unger, Elizabeth R

    2006-04-01

    Quantitative trait analysis (QTA) can be used to test whether the expression of a particular gene significantly correlates with some ordinal variable. To limit the number of false discoveries in the gene list, a multivariate permutation test can also be performed. The purpose of this study is to identify peripheral blood gene expression correlates of fatigue using quantitative trait analysis on gene expression data from 20,000 genes and fatigue traits measured using the multidimensional fatigue inventory (MFI). A total of 839 genes were statistically associated with fatigue measures. These mapped to biological pathways such as oxidative phosphorylation, gluconeogenesis, lipid metabolism, and several signal transduction pathways. However, more than 50% are not functionally annotated or associated with identified pathways. There is some overlap with genes implicated in other studies using differential gene expression. However, QTA allows detection of alterations that may not reach statistical significance in class comparison analyses, but which could contribute to disease pathophysiology. This study supports the use of phenotypic measures of chronic fatigue syndrome (CFS) and QTA as important for additional studies of this complex illness. Gene expression correlates of other phenotypic measures in the CFS Computational Challenge (C3) data set could be useful. Future studies of CFS should include as many precise measures of disease phenotype as is practical.

  3. Noise Minimisation in Gene Expression Switches

    PubMed Central

    Monteoliva, Diana; McCarthy, Christina B.; Diambra, Luis

    2013-01-01

    Gene expression is subject to stochastic variation which leads to fluctuations in the rate of protein production. Recently, a study in yeast at a genomic scale showed that, in some cases, gene expression variability alters phenotypes while, in other cases, these remain unchanged despite fluctuations in the expression of other genes. These studies suggested that noise in gene expression is a physiologically relevant trait and, to prevent harmful stochastic variation in the expression levels of some genes, it can be subject to minimisation. However, the mechanisms for noise minimisation are still unclear. In the present work, we analysed how noise expression depends on the architecture of the cis-regulatory system, in particular on the number of regulatory binding sites. Using analytical calculations and stochastic simulations, we found that the fluctuation level in noise expression decreased with the number of regulatory sites when regulatory transcription factors interacted with only one other bound transcription factor. In contrast, we observed that there was an optimal number of binding sites when transcription factors interacted with many bound transcription factors. This finding suggested a new mechanism for preventing large fluctuations in the expression of genes which are sensitive to the concentration of regulators. PMID:24376783

  4. Noise minimisation in gene expression switches.

    PubMed

    Monteoliva, Diana; McCarthy, Christina B; Diambra, Luis

    2013-01-01

    Gene expression is subject to stochastic variation which leads to fluctuations in the rate of protein production. Recently, a study in yeast at a genomic scale showed that, in some cases, gene expression variability alters phenotypes while, in other cases, these remain unchanged despite fluctuations in the expression of other genes. These studies suggested that noise in gene expression is a physiologically relevant trait and, to prevent harmful stochastic variation in the expression levels of some genes, it can be subject to minimisation. However, the mechanisms for noise minimisation are still unclear. In the present work, we analysed how noise expression depends on the architecture of the cis-regulatory system, in particular on the number of regulatory binding sites. Using analytical calculations and stochastic simulations, we found that the fluctuation level in noise expression decreased with the number of regulatory sites when regulatory transcription factors interacted with only one other bound transcription factor. In contrast, we observed that there was an optimal number of binding sites when transcription factors interacted with many bound transcription factors. This finding suggested a new mechanism for preventing large fluctuations in the expression of genes which are sensitive to the concentration of regulators.

  5. Influence of rimonabant treatment on peripheral blood mononuclear cells; flow cytometry analysis and gene expression profiling

    PubMed Central

    Almestrand, Stefan; Wang, Xiao; Jeppsson-Ahlberg, Åsa; Nordgren, Marcus; Flygare, Jenny; Christensson, Birger; Rössner, Stephan

    2015-01-01

    The cannabinoid receptor type 1 (CB1) antagonist rimonabant has been used as treatment for obesity. In addition, anti-proliferative effects on mitogen-activated leukocytes have been demonstrated in vitro. We have previously shown that rimonabant (SR141716A) induces cell death in ex vivo isolated malignant lymphomas with high expression of CB1 receptors. Since CB1 targeting may be part of a future lymphoma therapy, it was of interest to investigate possible effects on peripheral blood mononuclear cells (PBMC) in patients treated with rimonabant. We therefore evaluated leukocyte subsets by 6 color flow cytometry in eight patients before and at treatment with rimonabant for 4 weeks. Whole-transcript gene expression profiling in PBMC before and at 4 weeks of rimonabant treatment was done using Affymetrix Human Gene 1.0 ST Arrays. Our data show no significant changes of monocytes, B cells, total T cells or T cell subsets in PBMC during treatment with rimonabant. There was a small but significant increase in CD3–, CD16+ and/or CD56+ cells after rimonabant therapy. Gene expression analysis detected significant changes in expression of genes associated with innate immunity, cell death and metabolism. The present study shows that normal monocytes and leukocyte subsets in blood remain rather constant during rimonabant treatment. This is in contrast to the induction of cell death previously observed in CB1 expressing lymphoma cells in response to treatment with rimonabant in vitro. These differential effects observed on normal and malignant lymphoid cells warrant investigation of CB1 targeting as a potential lymphoma treatment. PMID:26157624

  6. Nucleosome repositioning underlies dynamic gene expression

    PubMed Central

    Nocetti, Nicolas; Whitehouse, Iestyn

    2016-01-01

    Nucleosome repositioning at gene promoters is a fundamental aspect of the regulation of gene expression. However, the extent to which nucleosome repositioning is used within eukaryotic genomes is poorly understood. Here we report a comprehensive analysis of nucleosome positions as budding yeast transit through an ultradian cycle in which expression of >50% of all genes is highly synchronized. We present evidence of extensive nucleosome repositioning at thousands of gene promoters as genes are activated and repressed. During activation, nucleosomes are relocated to allow sites of general transcription factor binding and transcription initiation to become accessible. The extent of nucleosome shifting is closely related to the dynamic range of gene transcription and generally related to DNA sequence properties and use of the coactivators TFIID or SAGA. However, dynamic gene expression is not limited to SAGA-regulated promoters and is an inherent feature of most genes. While nucleosome repositioning occurs pervasively, we found that a class of genes required for growth experience acute nucleosome shifting as cells enter the cell cycle. Significantly, our data identify that the ATP-dependent chromatin-remodeling enzyme Snf2 plays a fundamental role in nucleosome repositioning and the expression of growth genes. We also reveal that nucleosome organization changes extensively in concert with phases of the cell cycle, with large, regularly spaced nucleosome arrays being established in mitosis. Collectively, our data and analysis provide a framework for understanding nucleosome dynamics in relation to fundamental DNA-dependent transactions. PMID:26966245

  7. Nucleosome repositioning underlies dynamic gene expression.

    PubMed

    Nocetti, Nicolas; Whitehouse, Iestyn

    2016-03-15

    Nucleosome repositioning at gene promoters is a fundamental aspect of the regulation of gene expression. However, the extent to which nucleosome repositioning is used within eukaryotic genomes is poorly understood. Here we report a comprehensive analysis of nucleosome positions as budding yeast transit through an ultradian cycle in which expression of >50% of all genes is highly synchronized. We present evidence of extensive nucleosome repositioning at thousands of gene promoters as genes are activated and repressed. During activation, nucleosomes are relocated to allow sites of general transcription factor binding and transcription initiation to become accessible. The extent of nucleosome shifting is closely related to the dynamic range of gene transcription and generally related to DNA sequence properties and use of the coactivators TFIID or SAGA. However, dynamic gene expression is not limited to SAGA-regulated promoters and is an inherent feature of most genes. While nucleosome repositioning occurs pervasively, we found that a class of genes required for growth experience acute nucleosome shifting as cells enter the cell cycle. Significantly, our data identify that the ATP-dependent chromatin-remodeling enzyme Snf2 plays a fundamental role in nucleosome repositioning and the expression of growth genes. We also reveal that nucleosome organization changes extensively in concert with phases of the cell cycle, with large, regularly spaced nucleosome arrays being established in mitosis. Collectively, our data and analysis provide a framework for understanding nucleosome dynamics in relation to fundamental DNA-dependent transactions.

  8. Semaphorin and plexin gene expression is altered in the prefrontal cortex of schizophrenia patients with and without auditory hallucinations.

    PubMed

    Gilabert-Juan, Javier; Sáez, Ana Rosa; Lopez-Campos, Guillermo; Sebastiá-Ortega, Noelia; González-Martínez, Rocio; Costa, Juan; Haro, Josep María; Callado, Luis F; Meana, J Javier; Nacher, Juán; Sanjuán, Julio; Moltó, María Dolores

    2015-10-30

    Auditory hallucinations (AH) are clinical hallmarks of schizophrenia, however little is known about molecular genetics of these symptoms. In this study, gene expression profiling of postmortem brain samples from prefrontal cortex of schizophrenic patients without AH (SNA), patients with AH (SA) and control subjects were compared. Genome-wide expression analysis was conducted using samples of three individuals of each group and the Affymetrix GeneChip Human-Gene 1.0 ST-Array. This analysis identified the Axon Guidance pathway as one of the most differentially expressed network among SNA, SA and CNT. To confirm the transcriptome results, mRNA level quantification of seventeen genes involved in this pathway was performed in a larger sample. PLXNB1, SEMA3A, SEMA4D and SEM6C were upregulated in SNA or SA patients compared to controls. PLXNA1 and SEMA3D showed down-regulation in their expression in the patient's samples, but differences remained statistically significant between the SNA patients and controls. Differences between SNA and SA were found in PLXNB1 expression which is decreased in SA patients. This study strengthens the contribution of brain plasticity in pathophysiology of schizophrenia and shows that non-hallucinatory patients present more alterations in frontal regions than patients with hallucinations concerning neural plasticity.

  9. The action of a dietary retinoid on gene expression and cancer induction in electron-irradiated rat skin

    NASA Technical Reports Server (NTRS)

    Burns, Fredric J.; Chen, Shuaili; Xu, Guijuan; Wu, Feng; Tang, Moon-Shong

    2002-01-01

    Current models of radiation carcinogenesis generally assume that the DNA is damaged in a variety of ways by the radiation and that subsequent cell divisions contribute to the conversion of the damage to heritable mutations. Cancer may seem complex and intractable, but its complexity provides multiple opportunities for preventive interventions. Mitotic inhibitors are among the strongest cancer preventive agents, not only slowing the growth rate of preneoplasias but also increasing the fidelity of DNA repair processes. Ionizing radiation, including electrons, is a strong inducer of cancer in rat skin, and dietary retinoids have shown potent cancer preventive activity in the same system. A non-toxic dietary dose of retinyl acetate altered gene expression levels 24 hours after electron irradiation of rat skin. Of the 8740 genes on an Affymetrix rat expression array, the radiation significantly (5 fold or higher) altered 188, while the retinoid altered 231, including 16 radiation-altered genes that were reversely altered. While radiation strongly affected the expression of stress response, immune/inflammation and nucleic acid metabolism genes, the retinoid most strongly affected proliferation-related genes, including some significant reversals, such as, keratin 14, retinol binding protein, and calcium binding proteins. These results point to reversal of proliferation-relevant genes as a likely basis for the anti-radiogenic effects of dietary retinyl acetate.

  10. Sex-related gene expression profiles in the adrenal cortex in the mature rat: Microarray analysis with emphasis on genes involved in steroidogenesis

    PubMed Central

    TREJTER, MARCIN; HOCHOL, ANNA; TYCZEWSKA, MARIANNA; ZIOLKOWSKA, AGNIESZKA; JOPEK, KAROL; SZYSZKA, MARTA; MALENDOWICZ, LUDWIK K; RUCINSKI, MARCIN

    2015-01-01

    Notable sex-related differences exist in mammalian adrenal cortex structure and function. In adult rats, the adrenal weight and the average volume of zona fasciculata cells of females are larger and secrete greater amounts of corticosterone than those of males. The molecular bases of these sex-related differences are poorly understood. In this study, to explore the molecular background of these differences, we defined zone- and sex-specific transcripts in adult male and female (estrous cycle phase) rats. Twelve-week-old rats of both genders were used and samples were taken from the zona glomerulosa (ZG) and zona fasciculata/reticularis (ZF/R) zones. Transcriptome identification was carried out using the Affymetrix® Rat Gene 1.1 ST Array. The microarray data were compared by fold change with significance according to moderated t-statistics. Subsequently, we performed functional annotation clustering using the Gene Ontology (GO) and Database for Annotation, Visualization and Integrated Discovery (DAVID). In the first step, we explored differentially expressed transcripts in the adrenal ZG and ZF/R. The number of differentially expressed transcripts was notably higher in the female than in the male rats (702 vs. 571). The differentially expressed genes which were significantly enriched included genes involved in steroid hormone metabolism, and their expression levels in the ZF/R of adult female rats were significantly higher compared with those in the male rats. In the female ZF/R, when compared with that of the males, prevailing numbers of genes linked to cell fraction, oxidation/reduction processes, response to nutrients and to extracellular stimuli or steroid hormone stimuli were downregulated. The microarray data for key genes involved directly in steroidogenesis were confirmed by qPCR. Thus, when compared with that of the males, in the female ZF/R, higher expression levels of genes involved directly in steroid hormone synthesis were accompanied by lower

  11. Regulation of Flagellar Gene Expression in Bacteria.

    PubMed

    Osterman, I A; Dikhtyar, Yu Yu; Bogdanov, A A; Dontsova, O A; Sergiev, P V

    2015-11-01

    The flagellum of a bacterium is a supramolecular structure of extreme complexity comprising simultaneously both a unique system of protein transport and a molecular machine that enables the bacterial cell movement. The cascade of expression of genes encoding flagellar components is closely coordinated with the steps of molecular machine assembly, constituting an amazing regulatory system. Data on structure, assembly, and regulation of flagellar gene expression are summarized in this review. The regulatory mechanisms and correlation of the process of regulation of gene expression and flagellum assembly known from the literature are described. PMID:26615435

  12. Candidate reference genes for gene expression studies in water lily.

    PubMed

    Luo, Huolin; Chen, Sumei; Wan, Hongjian; Chen, Fadi; Gu, Chunsun; Liu, Zhaolei

    2010-09-01

    The selection of an appropriate reference gene(s) is a prerequisite for the proper interpretation of quantitative Real-Time polymerase chain reaction data. We report the evaluation of eight candidate reference genes across various tissues and treatments in the water lily by the two software packages geNorm and NormFinder. Across all samples, clathrin adaptor complexes medium subunit (AP47) and actin 11 (ACT11) emerged as the most suitable reference genes. Across different tissues, ACT11 and elongation factor 1-alpha (EF1alpha) exhibited a stable expression pattern. ACT11 and AP47 also stably expressed in roots subjected to various treatments, but in the leaves of the same plants the most stably expressed genes were ubiquitin-conjugating enzyme 16 (UBC16) and ACT11. PMID:20452325

  13. Expression of Polarity Genes in Human Cancer

    PubMed Central

    Lin, Wan-Hsin; Asmann, Yan W; Anastasiadis, Panos Z

    2015-01-01

    Polarity protein complexes are crucial for epithelial apical–basal polarity and directed cell migration. Since alterations of these processes are common in cancer, polarity proteins have been proposed to function as tumor suppressors or oncogenic promoters. Here, we review the current understanding of polarity protein functions in epithelial homeostasis, as well as tumor formation and progression. As most previous studies focused on the function of single polarity proteins in simplified model systems, we used a genomics approach to systematically examine and identify the expression profiles of polarity genes in human cancer. The expression profiles of polarity genes were distinct in different human tissues and classified cancer types. Additionally, polarity expression profiles correlated with disease progression and aggressiveness, as well as with identified cancer types, where specific polarity genes were commonly altered. In the case of Scribble, gene expression analysis indicated its common amplification and upregulation in human cancer, suggesting a tumor promoting function. PMID:25991909

  14. Optogenetic Control of Gene Expression in Drosophila

    PubMed Central

    Chan, Yick-Bun; Alekseyenko, Olga V.; Kravitz, Edward A.

    2015-01-01

    To study the molecular mechanism of complex biological systems, it is important to be able to artificially manipulate gene expression in desired target sites with high precision. Based on the light dependent binding of cryptochrome 2 and a cryptochrome interacting bHLH protein, we developed a split lexA transcriptional activation system for use in Drosophila that allows regulation of gene expression in vivo using blue light or two-photon excitation. We show that this system offers high spatiotemporal resolution by inducing gene expression in tissues at various developmental stages. In combination with two-photon excitation, gene expression can be manipulated at precise sites in embryos, potentially offering an important tool with which to examine developmental processes. PMID:26383635

  15. Expression of polarity genes in human cancer.

    PubMed

    Lin, Wan-Hsin; Asmann, Yan W; Anastasiadis, Panos Z

    2015-01-01

    Polarity protein complexes are crucial for epithelial apical-basal polarity and directed cell migration. Since alterations of these processes are common in cancer, polarity proteins have been proposed to function as tumor suppressors or oncogenic promoters. Here, we review the current understanding of polarity protein functions in epithelial homeostasis, as well as tumor formation and progression. As most previous studies focused on the function of single polarity proteins in simplified model systems, we used a genomics approach to systematically examine and identify the expression profiles of polarity genes in human cancer. The expression profiles of polarity genes were distinct in different human tissues and classified cancer types. Additionally, polarity expression profiles correlated with disease progression and aggressiveness, as well as with identified cancer types, where specific polarity genes were commonly altered. In the case of Scribble, gene expression analysis indicated its common amplification and upregulation in human cancer, suggesting a tumor promoting function.

  16. Regulation of Gene Expression in Protozoa Parasites

    PubMed Central

    Gomez, Consuelo; Esther Ramirez, M.; Calixto-Galvez, Mercedes; Medel, Olivia; Rodríguez, Mario A.

    2010-01-01

    Infections with protozoa parasites are associated with high burdens of morbidity and mortality across the developing world. Despite extensive efforts to control the transmission of these parasites, the spread of populations resistant to drugs and the lack of effective vaccines against them contribute to their persistence as major public health problems. Parasites should perform a strict control on the expression of genes involved in their pathogenicity, differentiation, immune evasion, or drug resistance, and the comprehension of the mechanisms implicated in that control could help to develop novel therapeutic strategies. However, until now these mechanisms are poorly understood in protozoa. Recent investigations into gene expression in protozoa parasites suggest that they possess many of the canonical machineries employed by higher eukaryotes for the control of gene expression at transcriptional, posttranscriptional, and epigenetic levels, but they also contain exclusive mechanisms. Here, we review the current understanding about the regulation of gene expression in Plasmodium sp., Trypanosomatids, Entamoeba histolytica and Trichomonas vaginalis. PMID:20204171

  17. Dynamic modeling of gene expression data

    NASA Technical Reports Server (NTRS)

    Holter, N. S.; Maritan, A.; Cieplak, M.; Fedoroff, N. V.; Banavar, J. R.

    2001-01-01

    We describe the time evolution of gene expression levels by using a time translational matrix to predict future expression levels of genes based on their expression levels at some initial time. We deduce the time translational matrix for previously published DNA microarray gene expression data sets by modeling them within a linear framework by using the characteristic modes obtained by singular value decomposition. The resulting time translation matrix provides a measure of the relationships among the modes and governs their time evolution. We show that a truncated matrix linking just a few modes is a good approximation of the full time translation matrix. This finding suggests that the number of essential connections among the genes is small.

  18. Functional gene expression differences between inbred alcohol-preferring and —non-prerats in five brain regions

    PubMed Central

    Kimpel, Mark W.; Strother, Wendy N.; McClintick, Jeanette N.; Carr, Lucinda G.; Liang, Tiebing; Edenberg, Howard J.; McBride, William J.

    2007-01-01

    The objective of this study was to determine if there are innate differences in gene expression in selected CNS regions between inbred alcohol-preferring (iP) and —non-preferring (iNP) rats. Gene expression was determined in the nucleus accumbens (ACB), amygdala (AMYG), frontal cortex (FC), caudate-putamen (CPU), and hippocampus (HIPP) of alcohol-naïve adult male iP and iNP rats, using Affymetrix Rat Genome U34A microarrays (n = 6/strain). Using Linear Modeling for Microarray Analysis with a false discovery rate threshold of 0.1, there were 16 genes with differential expression in the ACB, 54 in the AMYG, 8 in the FC, 24 in the CPU, and 21 in the HIPP. When examining the main effect of strain across regions, 296 genes were differentially expressed. Although the relatively small number of genes found significant within individual regions precluded a powerful analysis for over-represented Gene Ontology categories, the much larger list resulting from the main effect of strain analysis produced 17 over-represented categories (P <.05), including axon guidance, gliogenesis, negative regulation of programmed cell death, regulation of programmed cell death, regulation of synapse structure function, and transmission of nerve impulse. Co-citation analysis and graphing of significant genes revealed a network involved in the neuropeptide Y (NPY) transmitter system. Correlation of all significant genes with those located within previously established rat alcohol QTLs revealed that of the total of 313 significant genes, 71 are located within such QTLs. The many regional and overall gene expression differences between the iP and iNP rat lines may contribute to the divergent alcohol drinking phenotypes of these rats. PMID:17517326

  19. Altered gene expression patterns during the initiation and promotion stages of neonatally diethylstilbestrol-induced hyperplasia/dysplasia/neoplasia in the hamster uterus.

    PubMed

    Hendry, William J; Hariri, Hussam Y; Alwis, Imala D; Gunewardena, Sumedha S; Hendry, Isabel R

    2014-12-01

    Neonatal treatment of hamsters with diethylstilbestrol (DES) induces uterine hyperplasia/dysplasia/neoplasia (endometrial adenocarcinoma) in adult animals. We subsequently determined that the neonatal DES exposure event directly and permanently disrupts the developing hamster uterus (initiation stage) so that it responds abnormally when it is stimulated with estrogen in adulthood (promotion stage). To identify candidate molecular elements involved in progression of the disruption/neoplastic process, we performed: (1) immunoblot analyses and (2) microarray profiling (Affymetrix Gene Chip System) on sets of uterine protein and RNA extracts, respectively, and (3) immunohistochemical analysis on uterine sections; all from both initiation stage and promotion stage groups of animals. Here we report that: (1) progression of the neonatal DES-induced hyperplasia/dysplasia/neoplasia phenomenon in the hamster uterus involves a wide spectrum of specific gene expression alterations and (2) the gene products involved and their manner of altered expression differ dramatically during the initiation vs. promotion stages of the phenomenon.

  20. Increased leukemia-associated gene expression in benzene-exposed workers.

    PubMed

    Li, Keqiu; Jing, Yaqing; Yang, Caihong; Liu, Shasha; Zhao, Yuxia; He, Xiaobo; Li, Fei; Han, Jiayi; Li, Guang

    2014-07-04

    Long-term exposure to benzene causes several adverse health effects, including an increased risk of acute myeloid leukemia. This study was to identify genetic alternations involved in pathogenesis of leukemia in benzene-exposed workers without clinical symptoms of leukemia. This study included 33 shoe-factory workers exposed to benzene at levels from 1 ppm to 10 ppm. These workers were divided into 3 groups based on the benzene exposure time, 1- < 7, 7- < 12, and 12- < 24 years. 17 individuals without benzene exposure history were recruited as controls. Cytogenetic analysis using Affymetrix Cytogenetics Array found copy-number variations (CNVs) in several chromosomes of benzene-exposed workers. Expression of targeted genes in these altered chromosomes, NOTCH1 and BSG, which play roles in leukemia pathogenesis, was further examined using real-time PCR. The NOTCH1 mRNA level was significantly increased in all 3 groups of workers, and the NOTCH1 mRNA level in the 12- < 24 years group was significantly higher than that in 1- < 7 and 7- < 12 years groups. Compared to the controls, the BSG mRNA level was significantly increased in 7- < 12 and 12- < 24 years groups, but not in the 1- < 7 years group. These results suggest that CNVs and leukemia-related gene expression might play roles in leukemia development in benzene-exposed workers.

  1. Gene expression profiling of dengue infected human primary cells identifies secreted mediators in vivo

    PubMed Central

    Becerra, Aniuska; Warke, Rajas V.; Martin, Katherine; Xhaja, Kris; de Bosch, Norma; Rothman, Alan L.; Bosch, Irene

    2009-01-01

    We used gene expression profiling of human primary cells infected in vitro with dengue virus (DENV) as a tool to identify secreted mediators induced in response to the acute infection. Affymetrix Genechip analysis of human primary monocytes, B cells and dendritic cells infected with DENV in vitro revealed a strong induction of monocyte chemotactic protein 2 (MCP-2/CCL8), interferon gamma-induced protein 10 (IP-10/CXCL10) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/TNFSF10). The expression of these genes was confirmed in dendritic cells infected with DENV in vitro at mRNA and protein levels. A prospectively enrolled cohort of DENV-infected Venezuelan patients was used to measure the levels of these proteins in serum during three different periods of the disease. Results showed significant increase of MCP-2, IP-10 and TRAIL levels in DENV-infected patients during the febrile period, when compared to healthy donors and patients with other febrile illnesses. MCP-2 and IP-10 levels were still elevated during the post-febrile period while TRAIL levels dropped close to normal after defervescense. Patients with primary infections had higher TRAIL levels than patients with secondary infections during the febrile period of the disease. Increased levels of IP-10, TRAIL and MCP-2 in acute DENV infections suggest a role for these mediators in the immune response to the infection. PMID:19551822

  2. The number of genes changing expression after chronic exposure to code division multiple access or frequency DMA radiofrequency radiation does not exceed the false-positive rate.

    PubMed

    Whitehead, Timothy D; Moros, Eduardo G; Brownstein, Bernard H; Roti Roti, Joseph L

    2006-09-01

    Experiments with cultured C3H 10T 1/2 cells were performed to determine if exposure to cell phone radiofrequency (RF) radiations induce changes in gene expression. Following a 24 h exposure of 5 W/kg specific adsorption rate, RNA was extracted from the exposed and sham control cells for microarray analysis on Affymetrix U74Av2 Genechips. Cells exposed to 0.68 Gy of X-rays with a 4-h recovery were used as positive controls. The number of gene expression changes induced by RF radiation was not greater than the number of false positives expected based on a sham versus sham comparison. In contrast, the X-irradiated samples showed higher numbers of probe sets changing expression level than in the sham versus sham comparison.

  3. Testosterone-induced permanent changes of hepatic gene expression in female mice sustained during Plasmodium chabaudi malaria infection.

    PubMed

    Delić, Denis; Gailus, Nicole; Vohr, Hans-Werner; Dkhil, Mohamed; Al-Quraishy, Saleh; Wunderlich, Frank

    2010-12-01

    Testosterone has been previously shown to induce persistent susceptibility to Plasmodium chabaudi malaria in otherwise resistant female C57BL/6 mice. Here, we investigate as to whether this conversion coincides with permanent changes of hepatic gene expression profiles. Female mice aged 10-12 weeks were treated with testosterone for 3 weeks; then, testosterone treatment was discontinued for 12 weeks before challenging with 10⁶ P. chabaudi-infected erythrocytes. Hepatic gene expression was examined after 12 weeks of testosterone withdrawal and after subsequent infection with P. chabaudi at peak parasitemia, using Affymetrix microarrays with 22 ,690 probe sets representing 14, 000 genes. The expression of 54 genes was found to be permanently changed by testosterone, which remained changed during malaria infection. Most genes were involved in liver metabolism: the female-prevalent genes Cyp2b9, Cyp2b13, Cyp3a41, Cyp3a44, Fmo3, Sult2a2, Sult3a1, and BC014805 were repressed, while the male-prevalent genes Cyp2d9, Cyp7b1, Cyp4a10, Ugt2b1, Ugt2b38, Hsd3b5, and Slco1a1 were upregulated. Genes encoding different nuclear receptors were not persistently changed. Moreover, testosterone induced persistent upregulation of genes involved in hepatocellular carcinoma such as Lama3 and Nox4, whereas genes involved in immune response such as Ifnγ and Igk-C were significantly decreased. Our data provide evidence that testosterone is able to induce specific and robust long-term changes of gene expression profiles in the female mouse liver. In particular, those changes, which presumably indicate masculinized liver metabolism and impaired immune response, may be critical for the testosterone-induced persistent susceptibility of mice to P. chabaudi malaria. PMID:20844152

  4. Gene Positioning Effects on Expression in Eukaryotes.

    PubMed

    Nguyen, Huy Q; Bosco, Giovanni

    2015-01-01

    The packaging and organization of the genome within the eukaryotic interphase nucleus directly influence how the genes are expressed. An underappreciated aspect of genome structure is that it is highly dynamic and that the physical positioning of a gene can impart control over its transcriptional status. In this review, we assess the current knowledge of how gene positioning at different levels of genome organization can directly influence gene expression during interphase. The levels of organization discussed include chromatin looping, topologically associated domains, chromosome territories, and nuclear compartments. We discuss specific studies demonstrating that gene positioning is a dynamic and highly regulated feature of the eukaryotic genome that allows for the essential spatiotemporal regulation of genes.

  5. Homeobox genes expressed during echinoderm arm regeneration.

    PubMed

    Ben Khadra, Yousra; Said, Khaled; Thorndyke, Michael; Martinez, Pedro

    2014-04-01

    Regeneration in echinoderms has proved to be more amenable to study in the laboratory than the more classical vertebrate models, since the smaller genome size and the absence of multiple orthologs for different genes in echinoderms simplify the analysis of gene function during regeneration. In order to understand the role of homeobox-containing genes during arm regeneration in echinoderms, we isolated the complement of genes belonging to the Hox class that are expressed during this process in two major echinoderm groups: asteroids (Echinaster sepositus and Asterias rubens) and ophiuroids (Amphiura filiformis), both of which show an extraordinary capacity for regeneration. By exploiting the sequence conservation of the homeobox, putative orthologs of several Hox genes belonging to the anterior, medial, and posterior groups were isolated. We also report the isolation of a few Hox-like genes expressed in the same systems. PMID:24309817

  6. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis.

    PubMed

    dos Santos, Odelta; de Vargas Rigo, Graziela; Frasson, Amanda Piccoli; Macedo, Alexandre José; Tasca, Tiana

    2015-01-01

    Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR), one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis.

  7. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis.

    PubMed

    dos Santos, Odelta; de Vargas Rigo, Graziela; Frasson, Amanda Piccoli; Macedo, Alexandre José; Tasca, Tiana

    2015-01-01

    Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR), one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis. PMID:26393928

  8. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis

    PubMed Central

    dos Santos, Odelta; de Vargas Rigo, Graziela; Frasson, Amanda Piccoli; Macedo, Alexandre José; Tasca, Tiana

    2015-01-01

    Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR), one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis. PMID:26393928

  9. Diversity in global gene expression and morphology across a watercress (Nasturtium officinale R. Br.) germplasm collection: first steps to breeding

    PubMed Central

    Payne, Adrienne C.; Clarkson, Graham J.J.; Rothwell, Steve; Taylor, Gail

    2015-01-01

    Watercress (Nasturtium officinale R. Br.) is a nutrient intense, leafy crop that is consumed raw or in soups across the globe, but for which, currently no genomic resources or breeding programme exists. Promising morphological, biochemical and functional genomic variation was identified for the first time in a newly established watercress germplasm collection, consisting of 48 watercress accessions sourced from contrasting global locations. Stem length, stem diameter and anti-oxidant (AO) potential varied across the accessions. This variation was used to identify three extreme contrasting accessions for further analysis. Variation in global gene expression was investigated using an Affymetrix Arabidopsis ATH1 microarray gene chip, using the commercial control (C), an accession selected for dwarf phenotype with a high AO potential (dwarfAO, called ‘Boldrewood’) and one with high AO potential alone. A set of transcripts significantly differentially expressed between these three accessions, were identified, including transcripts involved in the regulation of growth and development and those involved in secondary metabolism. In particular, when differential gene expression was compared between C and dwarfAO, the dwarfAO was characterised by increased expression of genes encoding glucosinolates, which are known precursors of phenethyl isothiocyanate, linked to the anti-carcinogenic effects well-documented in watercress. This study provides the first analysis of natural variation across the watercress genome and has identified important underpinning information for future breeding for enhanced anti-carcinogenic properties and morphology traits in this nutrient-intense crop. PMID:26504575

  10. Diversity in global gene expression and morphology across a watercress (Nasturtium officinale R. Br.) germplasm collection: first steps to breeding.

    PubMed

    Payne, Adrienne C; Clarkson, Graham J J; Rothwell, Steve; Taylor, Gail

    2015-01-01

    Watercress (Nasturtium officinale R. Br.) is a nutrient intense, leafy crop that is consumed raw or in soups across the globe, but for which, currently no genomic resources or breeding programme exists. Promising morphological, biochemical and functional genomic variation was identified for the first time in a newly established watercress germplasm collection, consisting of 48 watercress accessions sourced from contrasting global locations. Stem length, stem diameter and anti-oxidant (AO) potential varied across the accessions. This variation was used to identify three extreme contrasting accessions for further analysis. Variation in global gene expression was investigated using an Affymetrix Arabidopsis ATH1 microarray gene chip, using the commercial control (C), an accession selected for dwarf phenotype with a high AO potential (dwarfAO, called 'Boldrewood') and one with high AO potential alone. A set of transcripts significantly differentially expressed between these three accessions, were identified, including transcripts involved in the regulation of growth and development and those involved in secondary metabolism. In particular, when differential gene expression was compared between C and dwarfAO, the dwarfAO was characterised by increased expression of genes encoding glucosinolates, which are known precursors of phenethyl isothiocyanate, linked to the anti-carcinogenic effects well-documented in watercress. This study provides the first analysis of natural variation across the watercress genome and has identified important underpinning information for future breeding for enhanced anti-carcinogenic properties and morphology traits in this nutrient-intense crop.

  11. Mechanisms of control of gene expression

    SciTech Connect

    Cullen, B.; Gage, L.P.; Siddiqui, M.A.Q.; Skalka, A.M.; Weissbach, H.

    1987-01-01

    This book examines an array of topics on the regulation of gene expression, including an examination of DNA-protein interactions and the role of oncogene proteins in normal and abnormal cellular responses. The book focuses on the control of mRNA transcription in eykaryotes and delineates other areas including gene regulation in prokaryotes and control of stable RNA synthesis.

  12. Perspectives: Gene Expression in Fisheries Management

    USGS Publications Warehouse

    Nielsen, Jennifer L.; Pavey, Scott A.

    2010-01-01

    Functional genes and gene expression have been connected to physiological traits linked to effective production and broodstock selection in aquaculture, selective implications of commercial fish harvest, and adaptive changes reflected in non-commercial fish populations subject to human disturbance and climate change. Gene mapping using single nucleotide polymorphisms (SNPs) to identify functional genes, gene expression (analogue microarrays and real-time PCR), and digital sequencing technologies looking at RNA transcripts present new concepts and opportunities in support of effective and sustainable fisheries. Genomic tools have been rapidly growing in aquaculture research addressing aspects of fish health, toxicology, and early development. Genomic technologies linking effects in functional genes involved in growth, maturation and life history development have been tied to selection resulting from harvest practices. Incorporating new and ever-increasing knowledge of fish genomes is opening a different perspective on local adaptation that will prove invaluable in wild fish conservation and management. Conservation of fish stocks is rapidly incorporating research on critical adaptive responses directed at the effects of human disturbance and climate change through gene expression studies. Genomic studies of fish populations can be generally grouped into three broad categories: 1) evolutionary genomics and biodiversity; 2) adaptive physiological responses to a changing environment; and 3) adaptive behavioral genomics and life history diversity. We review current genomic research in fisheries focusing on those that use microarrays to explore differences in gene expression among phenotypes and within or across populations, information that is critically important to the conservation of fish and their relationship to humans.

  13. Reading Genomes and Controlling Gene Expression

    NASA Astrophysics Data System (ADS)

    Libchaber, Albert

    2000-03-01

    Molecular recognition of DNA sequences is achieved by DNA hybridization of complementary sequences. We present various scenarios for optimization, leading to microarrays and global measurement. Gene expression can be controlled using gene constructs immobilized on a template with micron scale temperature heaters. We will discuss and present results on protein microarrays.

  14. Bayesian modeling of differential gene expression.

    PubMed

    Lewin, Alex; Richardson, Sylvia; Marshall, Clare; Glazier, Anne; Aitman, Tim

    2006-03-01

    We present a Bayesian hierarchical model for detecting differentially expressing genes that includes simultaneous estimation of array effects, and show how to use the output for choosing lists of genes for further investigation. We give empirical evidence that expression-level dependent array effects are needed, and explore different nonlinear functions as part of our model-based approach to normalization. The model includes gene-specific variances but imposes some necessary shrinkage through a hierarchical structure. Model criticism via posterior predictive checks is discussed. Modeling the array effects (normalization) simultaneously with differential expression gives fewer false positive results. To choose a list of genes, we propose to combine various criteria (for instance, fold change and overall expression) into a single indicator variable for each gene. The posterior distribution of these variables is used to pick the list of genes, thereby taking into account uncertainty in parameter estimates. In an application to mouse knockout data, Gene Ontology annotations over- and underrepresented among the genes on the chosen list are consistent with biological expectations.

  15. Inducible gene expression in transgenic Xenopus embryos.

    PubMed

    Wheeler, G N; Hamilton, F S; Hoppler, S

    2000-07-13

    The amphibian Xenopus laevis has been successfully used for many years as a model system for studying vertebrate development. Because of technical limitations, however, molecular investigations have mainly concentrated on early stages. We have developed a straightforward method for stage-specific induction of gene expression in transgenic Xenopus embryos [1] [2]. This method is based on the Xenopus heat shock protein 70 (Xhsp70 [3]) promoter driving the expression of desired gene products. We found that ubiquitous expression of the transgene is induced upon relatively mild heat treatment. Green fluorescent protein (GFP) was used as a marker to monitor successful induction of gene expression in transgenic embryos. We used this method to study the stage specificity of Wnt signalling function. Transient ectopic Wnt-8 expression during early neurulation was sufficient to repress anterior head development and this capacity was restricted to early stages of neurulation. By transient over-expression at different stages of development, we show that frizzled-7 disrupted morphogenesis sequentially from anterior to posterior along the dorsal axis as development proceeds. These results demonstrate that this method for inducible gene expression in transgenic Xenopus embryos will be a very powerful tool for temporal analysis of gene function and for studying molecular mechanisms of vertebrate organogenesis.

  16. Assessing Gene Expression of the Endocannabinoid System.

    PubMed

    Pucci, Mariangela; D'Addario, Claudio

    2016-01-01

    Real-time quantitative reverse transcription polymerase chain reaction (real-time qRT-PCR), a major development of PCR technology, is a powerful and sensitive gene analysis technique that revolutionized the field of measuring gene expression. Here, we describe in detail RNA extraction, reverse transcription (RT), and relative quantification of genes belonging to the endocannabinoid system in mouse, rat, or human samples. PMID:27245909

  17. Genome-wide analysis of differentially expressed genes and splicing isoforms in clear cell renal cell carcinoma.

    PubMed

    Valletti, Alessio; Gigante, Margherita; Palumbo, Orazio; Carella, Massimo; Divella, Chiara; Sbisà, Elisabetta; Tullo, Apollonia; Picardi, Ernesto; D'Erchia, Anna Maria; Battaglia, Michele; Gesualdo, Loreto; Pesole, Graziano; Ranieri, Elena

    2013-01-01

    Clear cell renal cell carcinoma (ccRCC) is the most common malignant renal epithelial tumor and also the most deadly. To identify molecular changes occurring in ccRCC, in the present study we performed a genome wide analysis of its entire complement of mRNAs. Gene and exon-level analyses were carried out by means of the Affymetrix Exon Array platform. To achieve a reliable detection of differentially expressed cassette exons we implemented a novel methodology that considered contiguous combinations of exon triplets and candidate differentially expressed cassette exons were identified when the expression level was significantly different only in the central exon of the triplet. More detailed analyses were performed for selected genes using quantitative RT-PCR and confocal laser scanning microscopy. Our analysis detected over 2,000 differentially expressed genes, and about 250 genes alternatively spliced and showed differential inclusion of specific cassette exons comparing tumor and non-tumoral tissues. We demonstrated the presence in ccRCC of an altered expression of the PTP4A3, LAMA4, KCNJ1 and TCF21 genes (at both transcript and protein level). Furthermore, we confirmed, at the mRNA level, the involvement of CAV2 and SFRP genes that have previously been identified. At exon level, among potential candidates we validated a differentially included cassette exon in DAB2 gene with a significant increase of DAB2 p96 splice variant as compared to the p67 isoform. Based on the results obtained, and their robustness according to both statistical analysis and literature surveys, we believe that a combination of gene/isoform expression signature may remarkably contribute, after suitable validation, to a more effective and reliable definition of molecular biomarkers for ccRCC early diagnosis, prognosis and prediction of therapeutic response. PMID:24194935

  18. Genome-Wide Analysis of Differentially Expressed Genes and Splicing Isoforms in Clear Cell Renal Cell Carcinoma

    PubMed Central

    Palumbo, Orazio; Carella, Massimo; Divella, Chiara; Sbisà, Elisabetta; Tullo, Apollonia; Picardi, Ernesto; D’Erchia, Anna Maria; Battaglia, Michele; Gesualdo, Loreto; Pesole, Graziano; Ranieri, Elena

    2013-01-01

    Clear cell renal cell carcinoma (ccRCC) is the most common malignant renal epithelial tumor and also the most deadly. To identify molecular changes occurring in ccRCC, in the present study we performed a genome wide analysis of its entire complement of mRNAs. Gene and exon-level analyses were carried out by means of the Affymetrix Exon Array platform. To achieve a reliable detection of differentially expressed cassette exons we implemented a novel methodology that considered contiguous combinations of exon triplets and candidate differentially expressed cassette exons were identified when the expression level was significantly different only in the central exon of the triplet. More detailed analyses were performed for selected genes using quantitative RT-PCR and confocal laser scanning microscopy. Our analysis detected over 2,000 differentially expressed genes, and about 250 genes alternatively spliced and showed differential inclusion of specific cassette exons comparing tumor and non-tumoral tissues. We demonstrated the presence in ccRCC of an altered expression of the PTP4A3, LAMA4, KCNJ1 and TCF21 genes (at both transcript and protein level). Furthermore, we confirmed, at the mRNA level, the involvement of CAV2 and SFRP genes that have previously been identified. At exon level, among potential candidates we validated a differentially included cassette exon in DAB2 gene with a significant increase of DAB2 p96 splice variant as compared to the p67 isoform. Based on the results obtained, and their robustness according to both statistical analysis and literature surveys, we believe that a combination of gene/isoform expression signature may remarkably contribute, after suitable validation, to a more effective and reliable definition of molecular biomarkers for ccRCC early diagnosis, prognosis and prediction of therapeutic response. PMID:24194935

  19. Transgenic overexpression of cdx1b induces metaplastic changes of gene expression in zebrafish esophageal squamous epithelium.

    PubMed

    Hu, Bo; Chen, Hao; Liu, Xiuping; Zhang, Chengjin; Cole, Gregory J; Lee, Ju-Ahng; Chen, Xiaoxin

    2013-06-01

    Cdx2 has been suggested to play an important role in Barrett's esophagus or intestinal metaplasia (IM) in the esophagus. To investigate whether transgenic overexpression of cdx1b, the functional equivalent of mammalian Cdx2 in zebrafish, may lead to IM of zebrafish esophageal squamous epithelium, a transgenic zebrafish system was developed by expressing cdx1b gene under the control of zebrafish keratin 5 promoter (krt5p). Gene expression in the esophageal squamous epithelium of wild-type and transgenic zebrafish was analyzed by Affymetrix microarray and confirmed by in situ hybridization. Morphology, mucin expression, cell proliferation, and apoptosis were analyzed by hematoxylin & eosin (HE) staining, Periodic acid Schiff (PAS) Alcian blue staining, proliferating cell nuclear antigen (PCNA) immunohistochemical staining, and TUNEL assay as well. cdx1b was found to be overexpressed in the nuclei of esophageal squamous epithelial cells of the transgenic zebrafish. Ectopic expression of cdx1b disturbed the development of this epithelium in larval zebrafish and induced metaplastic changes in gene expression in the esophageal squamous epithelial cells of adult zebrafish, that is, up-regulation of intestinal differentiation markers and down-regulation of squamous differentiation markers. However, cdx1b failed to induce histological IM, or to modulate cell proliferation and apoptosis in the squamous epithelium of adult transgenic zebrafish.

  20. Survival Online: a web-based service for the analysis of correlations between gene expression and clinical and follow-up data

    PubMed Central

    Corradi, Luca; Mirisola, Valentina; Porro, Ivan; Torterolo, Livia; Fato, Marco; Romano, Paolo; Pfeffer, Ulrich

    2009-01-01

    Background Complex microarray gene expression datasets can be used for many independent analyses and are particularly interesting for the validation of potential biomarkers and multi-gene classifiers. This article presents a novel method to perform correlations between microarray gene expression data and clinico-pathological data through a combination of available and newly developed processing tools. Results We developed Survival Online (available at ), a Web-based system that allows for the analysis of Affymetrix GeneChip microarrays by using a parallel version of dChip. The user is first enabled to select pre-loaded datasets or single samples thereof, as well as single genes or lists of genes. Expression values of selected genes are then correlated with sample annotation data by uni- or multi-variate Cox regression and survival analyses. The system was tested using publicly available breast cancer datasets and GO (Gene Ontology) derived gene lists or single genes for survival analyses. Conclusion The system can be used by bio-medical researchers without specific computation skills to validate potential biomarkers or multi-gene classifiers. The design of the service, the parallelization of pre-processing tasks and the implementation on an HPC (High Performance Computing) environment make this system a useful tool for validation on several independent datasets. PMID:19828070

  1. Gene expression from plants grown on the International Space Station

    NASA Astrophysics Data System (ADS)

    Stimpson, Alexander; Pereira, Rhea; Kiss, John Z.; Correll, Melanie

    Three experiments were performed on the International Space Station (ISS) in 2006 as part of the TROPI experiments. These experiments were performed to study graviTROPIsm and photoTROPIsm responses of Arabidopsis in microgravity (µg). Seedlings were grown with a variety of light and gravitational treatments for approximately five days. The frozen samples were returned to Earth during three space shuttle missions in 2007 and stored at -80° C. Due to the limited amount of plant biomass returned, new protocols were developed to minimize the amount of material needed for RNA extraction as a preparation for microarray analysis. Using these new protocols, RNA was extracted from several sets of seedlings grown in red light followed by blue light with one sample from 1.0g treatment and the other at µg. Using a 2-fold change criterion, microarray (Affymetrix, GeneChip) results showed that 613 genes were upregulated in the µg sample while 757 genes were downregulated. Upregulated genes in response to µg included transcription factors from the WRKY (15 genes), MYB (3) and ZF (8) families as well as those that are involved in auxin responses (10). Downregulated genes also included transcription factors such as MYB (5) and Zinc finger (10) but interestingly only two WRKY family genes were down-regulated during the µg treatment. Studies are underway to compare these results with other samples to identify the genes involved in the gravity and light signal transduction pathways (this project is Supported By: NASA NCC2-1200).

  2. Patterns of global gene expression in rat skeletal muscle during unloading and low-intensity ambulatory activity

    NASA Technical Reports Server (NTRS)

    Bey, Lionel; Akunuri, Nagabhavani; Zhao, Po; Hoffman, Eric P.; Hamilton, Deborah G.; Hamilton, Marc T.

    2003-01-01

    Physical inactivity and unloading lead to diverse skeletal muscle alterations. Our goal was to identify the genes in skeletal muscle whose expression is most sensitive to periods of unloading/reduced physical activity and that may be involved in triggering initial responses before phenotypic changes are evident. The ability of short periods of physical activity/loading as an effective countermeasure against changes in gene expression mediated by inactivity was also tested. Affymetrix microarrays were used to compare mRNA levels in the soleus muscle under three experimental treatments (n = 20-29 rats each): 12-h hindlimb unloading (HU), 12-h HU followed by 4 h of intermittent low-intensity ambulatory and postural activity (4-h reloading), and control (with ambulatory and postural activity). Using a combination of criteria, we identified a small set of genes (approximately 1% of 8,738 genes on the array or 4% of significant expressed genes) with the most reproducible and largest responses to altered activity. Analysis revealed a coordinated regulation of transcription for a large number of key signaling proteins and transcription factors involved in protein synthesis/degradation and energy metabolism. Most (21 of 25) of the gene expression changes that were downregulated during HU returned at least to control levels during the reloading. In surprising contrast, 27 of 38 of the genes upregulated during HU remained significantly above control, but most showed trends toward reversal. This introduces a new concept that, in general, genes that are upregulated during unloading/inactivity will be more resistant to periodic reloading than those genes that are downregulated. This study reveals genes that are the most sensitive to loading/activity in rat skeletal muscle and indicates new targets that may initiate muscle alterations during inactivity.

  3. Modeling gene expression in time and space.

    PubMed

    Rué, Pau; Garcia-Ojalvo, Jordi

    2013-01-01

    Cell populations rarely exhibit gene-expression profiles that are homogeneous in time and space. In the temporal domain, dynamical behaviors such as oscillations and pulses of protein production pervade cell biology, underlying phenomena as diverse as circadian rhythmicity, cell cycle control, stress and damage responses, and stem-cell pluripotency. In multicellular populations, spatial heterogeneities are crucial for decision making and development, among many other functions. Cells need to exquisitely coordinate this temporal and spatial variation to survive. Although the spatiotemporal character of gene expression is challenging to quantify experimentally at the level of individual cells, it is beneficial from the modeling viewpoint, because it provides strong constraints that can be probed by theoretically analyzing mathematical models of candidate gene and protein circuits. Here, we review recent examples of temporal dynamics and spatial patterning in gene expression to show how modeling such phenomenology can help us unravel the molecular mechanisms of cellular function.

  4. Introduction to the Gene Expression Analysis.

    PubMed

    Segundo-Val, Ignacio San; Sanz-Lozano, Catalina S

    2016-01-01

    In 1941, Beadle and Tatum published experiments that would explain the basis of the central dogma of molecular biology, whereby the DNA through an intermediate molecule, called RNA, results proteins that perform the functions in cells. Currently, biomedical research attempts to explain the mechanisms by which develops a particular disease, for this reason, gene expression studies have proven to be a great resource. Strictly, the term "gene expression" comprises from the gene activation until the mature protein is located in its corresponding compartment to perform its function and contribute to the expression of the phenotype of cell.The expression studies are directed to detect and quantify messenger RNA (mRNA) levels of a specific gene. The development of the RNA-based gene expression studies began with the Northern Blot by Alwine et al. in 1977. In 1969, Gall and Pardue and John et al. independently developed the in situ hybridization, but this technique was not employed to detect mRNA until 1986 by Coghlan. Today, many of the techniques for quantification of RNA are deprecated because other new techniques provide more information. Currently the most widely used techniques are qPCR, expression microarrays, and RNAseq for the transcriptome analysis. In this chapter, these techniques will be reviewed. PMID:27300529

  5. Thyroid-specific gene expression in chondrocytes.

    PubMed

    Endo, Toyoshi; Kobayashi, Tetsuro

    2011-12-16

    Previously, we demonstrated that Runx2 (Cbfa1/AML3), a chondrocyte-specific transcription factor, is expressed in thyroid glands of mice, where it stimulates expression of the thyroglobulin (Tg) gene. Here, we reverse transcribed thyroid transcription factor-1 (TTF-1), Pax-8, Tg, thyroid peroxidase (TPO) and Na(+)/I(-) symporter (NIS) cDNAs from mouse trachea and bronchus RNA samples, but were unable to recover these cDNAs from mouse liver RNA samples. Tg mRNA levels in trachea and bronchus were about 5.1% and 2.1% of those in thyroid glands. ATDC-5 cells, cultured chondrocytes, expressed about 30-fold more Tg mRNA than undifferentiated cells. Gel shift and Tg gene reporter assay revealed that TTF-1 stimulated Tg gene expression in these cells. These results indicate that chondrocytes turn on some aspects of the thyroid gene expression program and that TTF-1 plays important roles in Tg gene expression in chondrocyte. PMID:21945616

  6. Cumulus Cells Gene Expression Profiling in Terms of Oocyte Maturity in Controlled Ovarian Hyperstimulation Using GnRH Agonist or GnRH Antagonist

    PubMed Central

    Devjak, Rok; Fon Tacer, Klementina; Juvan, Peter; Virant Klun, Irma; Rozman, Damjana; Vrtačnik Bokal, Eda

    2012-01-01

    In in vitro fertilization (IVF) cycles controlled ovarian hyperstimulation (COH) is established by gonadotropins in combination with gonadotropin-releasing hormone (GnRH) agonists or antagonists, to prevent premature luteinizing hormone (LH) surge. The aim of our study was to improve the understanding of gene expression profile of cumulus cells (CC) in terms of ovarian stimulation protocol and oocyte maturity. We applied Affymetrix gene expression profiling in CC of oocytes at different maturation stages using either GnRH agonists or GnRH antagonists. Two analyses were performed: the first involved CC of immature metaphase I (MI) and mature metaphase II (MII) oocytes where 359 genes were differentially expressed, and the second involved the two GnRH analogues where no differentially expressed genes were observed at the entire transcriptome level. A further analysis of 359 differentially genes was performed, focusing on anti-Müllerian hormone receptor 2 (AMHR2), follicle stimulating hormone receptor (FSHR), vascular endothelial growth factor C (VEGFC) and serine protease inhibitor E2 (SERPINE2). Among other differentially expressed genes we observed a marked number of new genes connected to cell adhesion and neurotransmitters such as dopamine, glycine and γ-Aminobutyric acid (GABA). No differential expression in CC between the two GnRH analogues supports the findings of clinical studies where no significant difference in live birth rates between both GnRH analogues has been proven. PMID:23082142

  7. Alterations in gene expression in rat skin exposed to 56Fe ions and dietary vitamin A acetate.

    PubMed

    Zhang, Ronghe; Burns, Fredric J; Chen, Haobin; Chen, Shuaili; Wu, Feng

    2006-05-01

    The purpose of the present work was to examine gene expression patterns in rat skin exposed to a beam of (56)Fe ions, a surrogate for the high-energy, heavy-ion galactic radiation background, as a basis for obtaining a better understanding of the possible mechanism(s) behind the radioprotective activity of vitamin A. A 2 x 4-cm rectangle of dorsal rat skin was exposed to 1.01 GeV/nucleon (56)Fe ions generated by the Alternating Gradient Synchrotron at Brookhaven National Laboratory. Gene expression patterns were monitored in either the presence or absence of a 250-ppm dietary supplement of vitamin A acetate in powdered lab chow. Although vitamin A and other retinoids show anti-carcinogenic activity in several animal models, the underlying changes in gene expression have not been examined extensively. At either 1 or 7 day after irradiation, a 1-cm square of irradiated and control rat skin was excised and analyzed using the Affymetrix rat microarray (RG_U34A) system. Microarray responses were displayed and processed by GeneSpring 7.0 and GOTree software. At 1 day after 3 Gy of (56)Fe-ion irradiation, the expression of 110 genes was significantly up-regulated (P < = 0.05) in comparison to levels in control rat skin, while no genes were altered by the vitamin A acetate supplement alone. Combined with (56)Fe-ion radiation, the vitamin A acetate supplement blocked the expression of 88 (80%) of the 110 genes and eliminated 16 of 18 gene categories that were significantly altered (all increased) by the (56)Fe-ion radiation. Categories with large numbers of genes eliminated by the retinoid included response to stress, 33 genes; response to biotic stimulus, 38 genes; signal transduction, 35 genes; and regulation of cellular/physiological process, 40 genes. Even for immune response and response to biotic stimulus, the only two categories that remained significantly altered in the presence of the vitamin, the combined number of altered genes was reduced from 74 to 13. No

  8. Regulation of gene expression in human tendinopathy

    PubMed Central

    2011-01-01

    Background Chronic tendon injuries, also known as tendinopathies, are common among professional and recreational athletes. These injuries result in a significant amount of morbidity and health care expenditure, yet little is known about the molecular mechanisms leading to tendinopathy. Methods We have used histological evaluation and molecular profiling to determine gene expression changes in 23 human patients undergoing surgical procedures for the treatment of chronic tendinopathy. Results Diseased tendons exhibit altered extracellular matrix, fiber disorientation, increased cellular content and vasculature, and the absence of inflammatory cells. Global gene expression profiling identified 983 transcripts with significantly different expression patterns in the diseased tendons. Global pathway analysis further suggested altered expression of extracellular matrix proteins and the lack of an appreciable inflammatory response. Conclusions Identification of the pathways and genes that are differentially regulated in tendinopathy samples will contribute to our understanding of the disease and the development of novel therapeutics. PMID:21539748

  9. Mid-Gestational Gene Expression Profile in Placenta and Link to Pregnancy Complications

    PubMed Central

    Uusküla, Liis; Männik, Jaana; Rull, Kristiina; Minajeva, Ave; Kõks, Sulev; Vaas, Pille; Teesalu, Pille; Reimand, Jüri; Laan, Maris

    2012-01-01

    Despite the importance of placenta in mediating rapid physiological changes in pregnancy, data on temporal dynamics of placental gene expression are limited. We completed the first transcriptome profiling of human placental gene expression dynamics (GeneChips, Affymetrix®; ∼47,000 transcripts) from early to mid-gestation (n = 10; gestational weeks 5–18) and report 154 genes with significant transcriptional changes (ANOVA, FDR P<0.1). TaqMan RT-qPCR analysis (n = 43; gestational weeks 5–41) confirmed a significant (ANOVA and t-test, FDR P<0.05) mid-gestational peak of placental gene expression for BMP5, CCNG2, CDH11, FST, GATM, GPR183, ITGBL1, PLAGL1, SLC16A10 and STC1, followed by sharp decrease in mRNA levels at term (t-test, FDR P<0.05). We hypothesized that normal course of late pregnancy may be affected when genes characteristic to mid-gestation placenta remain highly expressed until term, and analyzed their expression in term placentas from normal and complicated pregnancies [preeclampsia (PE), n = 12; gestational diabetes mellitus (GDM), n = 12; small- and large-for-gestational-age newborns (SGA, LGA), n = 12+12]. STC1 (stanniocalcin 1) exhibited increased mRNA levels in all studied complications, with the most significant effect in PE- and SGA-groups (t-test, FDR P<0.05). In post-partum maternal plasma, the highest STC1 hormone levels (ELISA, n = 129) were found in women who had developed PE and delivered a SGA newborn (median 731 vs 418 pg/ml in controls; ANCOVA, P = 0.00048). Significantly higher expression (t-test, FDR P<0.05) of CCNG2 and LYPD6 accompanied with enhanced immunostaining of the protein was detected in placental sections of PE and GDM cases (n = 15). Our study demonstrates the importance of temporal dynamics of placental transcriptional regulation across three trimesters of gestation. Interestingly, many genes with high expression in mid-gestation placenta have also been implicated in adult complex

  10. Differential gene expression in mouse retina related to regional differences in vulnerability to hyperoxia

    PubMed Central

    Natoli, Riccardo; Valter, Krisztina; Stone, Jonathan

    2010-01-01

    Purpose In the C57BL/6J mouse retina, hyperoxia-induced degeneration of photoreceptors shows strong regional variation, beginning at a locus ~0.5 mm inferior to the optic disc. To identify gene expression differences that might underlie this variability in vulnerability, we have used microarray techniques to describe regional (superior-inferior) variations in gene expression in the retina. Methods Young adult C57BL/6J mice raised in dim cyclic illumination (12 h at 5 lx and 12 h in darkness) were exposed to hyperoxia (75% oxygen for two weeks). Retinas were collected from hyperoxia-exposed and control animals without fixation and divided into superior and inferior halves. RNA was extracted from each sample, purified, and hybridized to Mouse Gene 1.0 ST arrays (Affymetrix). The consistency of the microarray results was assessed using quantitative PCR for selected genes. Expression data were analyzed to identify genes and ncRNAs whose differential expression between the superior and inferior retina could be associated with relative vulnerability to hyperoxia. Results In control retinas, only two genes showed a fold difference in expression >2 between the superior and inferior retina; another 25 showed a fold difference of 1.5–2.0. Of these 27, the functions of six genes, including ventral anterior homeobox containing gene 2 (Vax2) and T-box 5 (Tbox5), are related to parameters of anatomic development and the functions of five are related to sensory perception. Among the latter, short-wave-sensitive cone opsin (Opn1sw) was more strongly expressed in the inferior retina and medium-wave-sensitive cone opsin (Opn1mw) in the superior retina. This is consistent with known differences in S- and M-cone distribution, confirming our separation of retinal regions. The highest fold difference was reported for membrane metalloendopeptidase (Mme), a member from the metallothionein group of cytoprotective proteins. To identify genes whose regulation by hyperoxia was

  11. Altered gene expression in rat mesenteric tissue following in vivo exposure to a phosphodiesterase 4 inhibitor

    SciTech Connect

    Dagues, Nicolas . E-mail: nicolas.dagues@pfizer.com; Pawlowski, Valerie; Guigon, Ghislaine; Ledieu, David; Sobry, Cecile; Hanton, Gilles; Freslon, Jean-Louis; Chevalier, Stephan

    2007-01-01

    Vascular injury is a relatively common finding during the pre-clinical toxicity testing of drugs. The mechanisms of the injury are poorly understood and in turn, sensitive and specific biomarkers for pre-clinical and clinical monitoring do not exist. The present study was undertaken to investigate the molecular mechanisms of drug-induced vascular injury in mesenteric tissue of rats treated with the selective phosphodiesterase 4 (PDE4) inhibitor CI-1044. In a time-course study, male Sprague Dawley rats were given daily doses of 40 or 80 mg/kg for 1, 2 or 3 successive days and were euthanized the following day. Gene expression profiles in mesenteric tissue were determined using Affymetrix RG{sub U}34A microarrays and fibrinogen and cytokine measurements were performed in blood samples. Hierarchical clustering analysis produced a clear pattern separation of the animals with inflammation, animal with inflammation and necrosis and animals without any lesion. Genes associated with inflammation, procoagulation, extracellular matrix remodeling were up-regulated. An altered expression of genes involved in vascular tone regulation, lipid and glucose metabolism was also observed. Selected genes expression changes were confirmed by TaqMan real-time RT-PCR. The inflammatory process was also detected in the bloodstream at the protein level since fibrinogen, IL6 and IL1{beta} concentrations were increased in treated animals. Overall, the present study reveals several molecular changes supporting the hypothesis by which PDE4 inhibitor-induced vascular lesions in rats are triggered by an inflammatory mechanism and/or a vascular tone dysregulation.

  12. Intergrin gene expression profiles of humanhepatocellular carcinoma

    PubMed Central

    Liu, Lian-Xin; Jiang, Hong-Chi; Liu, Zhi-Hua; Zhou, Jing; Zhang, Wei-Hui; Zhu, An-Long; Wang, Xiu-Qin; Wu, Min

    2002-01-01

    AIM: To investigate gene expression profiles of intergrin genes in hepatocellular carcinoma (HCC) through the usage of Atlas Human Cancer Array membranes, semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Northern blot. METHODS: Hybridization of cDNA array membrane was performed with α 32P-labeled cDNA probes synthesized from RNA isolated from hepatocellular carcinoma and adjacent non-cirrhotic liver. AtlasImage, which is a software specific to array, was used to analyze the result. RT-PCR of 24 pairs specimen and Northern blot of 4 pairs specimen were used to confirm the expression pattern of some intergrin genes identified by Atlas arrays hybridization. RESULTS: Among 588 genes spotted in membrane, 17 genes were related to intergrin. Four genes were up-regulated, such as intergrin alpha8, beta1, beta7 and beta8 in HCC. Whereas there were no genes down-regulated in HCC. RT-PCR and Northern blot analysis of intergrin beta1 gene gave results consistent with cDNA array findings. CONCLUSION: Investigation of these intergrin genes should help to disclose the molecular mechanism of the cell adhesion, invasive and metastasis of HCC. A few genes are reported to have changed in HCC for the first time. The quick and high-throughout method of profiling gene expression by cDNA array provides us overview of key factors that may involved in HCC, and may find the clue of the study of HCC metastasis and molecular targets of anti-metastasis therapy. The precise relationship between the altered genes and HCC is a matter of further investigation. PMID:12174369

  13. Noise minimization in eukaryotic gene expression

    SciTech Connect

    Fraser, Hunter B.; Hirsh, Aaron E.; Giaever, Guri; Kumm, Jochen; Eisen, Michael B.

    2004-01-15

    All organisms have elaborate mechanisms to control rates of protein production. However, protein production is also subject to stochastic fluctuations, or noise. Several recent studies in Saccharomyces cerevisiae and Escherichia coli have investigated the relationship between transcription and translation rates and stochastic fluctuations in protein levels, or more generally, how such randomness is a function of intrinsic and extrinsic factors. However, the fundamental question of whether stochasticity in protein expression is generally biologically relevant has not been addressed, and it remains unknown whether random noise in the protein production rate of most genes significantly affects the fitness of any organism. We propose that organisms should be particularly sensitive to variation in the protein levels of two classes of genes: genes whose deletion is lethal to the organism and genes that encode subunits of multiprotein complexes. Using an experimentally verified model of stochastic gene expression in S. cerevisiae, we estimate the noise in protein production for nearly every yeast gene, and confirm our prediction that the production of essential and complex-forming proteins involves lower levels of noise than does the production of most other genes. Our results support the hypothesis that noise in gene expression is a biologically important variable, is generally detrimental to organismal fitness, and is subject to natural selection.

  14. Soybean physiology and gene expression during drought.

    PubMed

    Stolf-Moreira, R; Medri, M E; Neumaier, N; Lemos, N G; Pimenta, J A; Tobita, S; Brogin, R L; Marcelino-Guimarães, F C; Oliveira, M C N; Farias, J R B; Abdelnoor, R V; Nepomuceno, A L

    2010-10-05

    Soybean genotypes MG/BR46 (Conquista) and BR16, drought-tolerant and -sensitive, respectively, were compared in terms of morphophysiological and gene-expression responses to water stress during two stages of development. Gene-expression analysis showed differential responses in Gmdreb1a and Gmpip1b mRNA expression within 30 days of water-deficit initiation in MG/BR46 (Conquista) plants. Within 45 days of initiating stress, Gmp5cs and Gmpip1b had relatively higher expression. Initially, BR16 showed increased expression only for Gmdreb1a, and later (45 days) for Gmp5cs, Gmdefensin and Gmpip1b. Only BR16 presented down-regulated expression of genes, such as Gmp5cs and Gmpip1b, 30 days after the onset of moisture stress, and Gmgols after 45 days of stress. The faster perception of water stress in MG/BR46 (Conquista) and the better maintenance of up-regulated gene expression than in the sensitive BR16 genotype imply mechanisms by which the former is better adapted to tolerate moisture deficiency.

  15. Gene Expression Changes for Antioxidants Pathways in the Mouse Cochlea: Relations to Age-related Hearing Deficits

    PubMed Central

    Tadros, Sherif F.; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D.

    2014-01-01

    Age-related hearing loss – presbycusis – is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively) may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear – cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis. PMID:24587312

  16. Gene expression changes for antioxidants pathways in the mouse cochlea: relations to age-related hearing deficits.

    PubMed

    Tadros, Sherif F; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D

    2014-01-01

    Age-related hearing loss - presbycusis - is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively) may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear - cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis.

  17. Perturbation of Staphylococcus aureus Gene Expression by the Enoyl-Acyl Carrier Protein Reductase Inhibitor AFN-1252

    PubMed Central

    Parsons, Joshua B.; Kukula, Maciej; Jackson, Pamela; Pulse, Mark; Simecka, Jerry W.; Valtierra, David; Weiss, William J.; Kaplan, Nachum

    2013-01-01

    This study examines the alteration in Staphylococcus aureus gene expression following treatment with the type 2 fatty acid synthesis inhibitor AFN-1252. An Affymetrix array study showed that AFN-1252 rapidly increased the expression of fatty acid synthetic genes and repressed the expression of virulence genes controlled by the SaeRS 2-component regulator in exponentially growing cells. AFN-1252 did not alter virulence mRNA levels in a saeR deletion strain or in strain Newman expressing a constitutively active SaeS kinase. AFN-1252 caused a more pronounced increase in fabH mRNA levels in cells entering stationary phase, whereas the depression of virulence factor transcription was attenuated. The effect of AFN-1252 on gene expression in vivo was determined using a mouse subcutaneous granuloma infection model. AFN-1252 was therapeutically effective, and the exposure (area under the concentration-time curve from 0 to 48 h [AUC0–48]) of AFN-1252 in the pouch fluid was comparable to the plasma levels in orally dosed animals. The inhibition of fatty acid biosynthesis by AFN-1252 in the infected pouches was signified by the substantial and sustained increase in fabH mRNA levels in pouch-associated bacteria, whereas depression of virulence factor mRNA levels in the AFN-1252-treated pouch bacteria was not as evident as it was in exponentially growing cells in vitro. The trends in fabH and virulence factor gene expression in the animal were similar to those in slower-growing bacteria in vitro. These data indicate that the effects of AFN-1252 on virulence factor gene expression depend on the physiological state of the bacteria. PMID:23459481

  18. Inferring differentiation pathways from gene expression

    PubMed Central

    Costa, Ivan G.; Roepcke, Stefan; Hafemeister, Christoph; Schliep, Alexander

    2008-01-01

    Motivation: The regulation of proliferation and differentiation of embryonic and adult stem cells into mature cells is central to developmental biology. Gene expression measured in distinguishable developmental stages helps to elucidate underlying molecular processes. In previous work we showed that functional gene modules, which act distinctly in the course of development, can be represented by a mixture of trees. In general, the similarities in the gene expression programs of cell populations reflect the similarities in the differentiation path. Results: We propose a novel model for gene expression profiles and an unsupervised learning method to estimate developmental similarity and infer differentiation pathways. We assess the performance of our model on simulated data and compare it with favorable results to related methods. We also infer differentiation pathways and predict functional modules in gene expression data of lymphoid development. Conclusions: We demonstrate for the first time how, in principal, the incorporation of structural knowledge about the dependence structure helps to reveal differentiation pathways and potentially relevant functional gene modules from microarray datasets. Our method applies in any area of developmental biology where it is possible to obtain cells of distinguishable differentiation stages. Availability: The implementation of our method (GPL license), data and additional results are available at http://algorithmics.molgen.mpg.de/Supplements/InfDif/ Contact: filho@molgen.mpg.de, schliep@molgen.mpg.de Supplementary information: Supplementary data is available at Bioinformatics online. PMID:18586709

  19. Altered gene expression in dry age-related macular degeneration suggests early loss of choroidal endothelial cells

    PubMed Central

    Whitmore, S. Scott; Braun, Terry A.; Skeie, Jessica M.; Haas, Christine M.; Sohn, Elliott H.; Stone, Edwin M.; Scheetz, Todd E.

    2013-01-01

    Purpose Age-related macular degeneration (AMD) is a major cause of blindness in developed countries. The molecular pathogenesis of early events in AMD is poorly understood. We investigated differential gene expression in samples of human retinal pigment epithelium (RPE) and choroid from early AMD and control maculas with exon-based arrays. Methods Gene expression levels in nine human donor eyes with early AMD and nine control human donor eyes were assessed using Affymetrix Human Exon ST 1.0 arrays. Two controls did not pass quality control and were removed. Differentially expressed genes were annotated using the Database for Annotation, Visualization and Integrated Discovery (DAVID), and gene set enrichment analysis (GSEA) was performed on RPE-specific and endothelium-associated gene sets. The complement factor H (CFH) genotype was also assessed, and differential expression was analyzed regarding high AMD risk (YH/HH) and low AMD risk (YY) genotypes. Results Seventy-five genes were identified as differentially expressed (raw p value <0.01; ≥50% fold change, mean log2 expression level in AMD or control ≥ median of all average gene expression values); however, no genes were significant (adj. p value <0.01) after correction for multiple hypothesis testing. Of 52 genes with decreased expression in AMD (fold change <0.5; raw p value <0.01), 18 genes were identified by DAVID analysis as associated with vision or neurologic processes. The GSEA of the RPE-associated and endothelium-associated genes revealed a significant decrease in genes typically expressed by endothelial cells in the early AMD group compared to controls, consistent with previous histologic and proteomic studies. Analysis of the CFH genotype indicated decreased expression of ADAMTS9 in eyes with high-risk genotypes (fold change = –2.61; raw p value=0.0008). Conclusions GSEA results suggest that RPE transcripts are preserved or elevated in early AMD, concomitant with loss of endothelial cell marker

  20. Human AZU-1 gene, variants thereof and expressed gene products

    DOEpatents

    Chen, Huei-Mei; Bissell, Mina

    2004-06-22

    A human AZU-1 gene, mutants, variants and fragments thereof. Protein products encoded by the AZU-1 gene and homologs encoded by the variants of AZU-1 gene acting as tumor suppressors or markers of malignancy progression and tumorigenicity reversion. Identification, isolation and characterization of AZU-1 and AZU-2 genes localized to a tumor suppressive locus at chromosome 10q26, highly expressed in nonmalignant and premalignant cells derived from a human breast tumor progression model. A recombinant full length protein sequences encoded by the AZU-1 gene and nucleotide sequences of AZU-1 and AZU-2 genes and variant and fragments thereof. Monoclonal or polyclonal antibodies specific to AZU-1, AZU-2 encoded protein and to AZU-1, or AZU-2 encoded protein homologs.

  1. Influence of Smoking on Colonic Gene Expression Profile in Crohn's Disease

    PubMed Central

    Nielsen, Ole Haagen; Bjerrum, Jacob Tveiten; Csillag, Claudio; Nielsen, Finn Cilius; Olsen, Jørgen

    2009-01-01

    Background The development and course of Crohn's disease (CD) is related to both genetic and environmental factors. Smoking has been found to exacerbate the course of CD by increasing the risk of developing fistulas and strictures as well as the need for surgery, possibly because of an interaction between smoking or nicotine on macrophage function and the intestinal microvasculature. Several genes are involved in the pathogenesis of CD, and in this study the gene expression differences of the descending colonic mucosa were investigated in CD (smokers or never smokers) and controls (smokers or never smokers). Aim To identify any difference in gene expression of the descending colonic mucosa between smoking and never-smoking CD patients (and controls) by determining genetic expression profiles from microarray analysis. Methods Fifty-seven specimens were obtained by routine colonoscopy from the included material: CD smokers (n = 28) or never-smokers (n = 14) as compared to fifteen healthy controls (8 smokers and 7 never-smokers). RNA was isolated and gene expression assessed with Affymetrix GeneChip Human Genome U133 Plus 2.0. Data were analyzed by principal component analysis (PCA), Wilcoxon rank sum test and multiple linear regressions. Real-time (RT) PCR was subsequently applied to verify microarray results. Results The PCA analysis showed no intrinsic clustering of smokers versus never-smokers. However, when Wilcoxon rank sum test corrected with Q values were performed, six known genes were significantly expressed differently in the inflamed CD smokers as compared to the inflamed CD never-smokers: ring finger protein 138 (RNF138), metalothionein 2A (MT2A) and six transmembrane epithelial antigen of the prostate 3 (STEAP3), SA hypertension-associated homolog, PGM2L1 and KCNJ2. The subsequent RT-PCR-analyses verified, however, that only RNF138, MT2A and STEAP3 were significantly up-regulated in CD smokers in specimens with inflammatory activity of the

  2. [Expression and regulation of the SOST gene].

    PubMed

    Qin, Long-Juan; Ding, Da-Xia; Cui, Lu-Lu; Huang, Qing-Yang

    2013-08-01

    Sclerostin(SOST), mainly expressed in osteocytes, is a negative regulator of bone formation. Hormones PTH and E2 inhibit the expression of the SOST gene. Transcription factors Osterix, Runx2, and Mef2c promote the SOST expression, while Sirt1 negatively regulates the SOST expression. In addition, the expression of the SOST gene is regulated by epigenetic mechanisms, such as DNA methylation and microRNA. Mutations in the SOST gene, which cause sclerosteosis and Van Buchem diseases, are associated with osteoporosis. Wnt and BMP are two important signaling pathways in bone metabolic regulation. SOST can regulate osteoblastic differentiation and bone formation by binding type I/II receptors and co-receptor LRP5/6 to inhibit BMP and Wnt signaling pathways. Suppression of SOST provides a new approach for osteoporosis treatment. This review covers the structure, function and expression regulation of the SOST gene, human disease association, mechanism in the regulation of bone metabolism and prospect in clinical application.

  3. Alternative-splicing-mediated gene expression

    NASA Astrophysics Data System (ADS)

    Wang, Qianliang; Zhou, Tianshou

    2014-01-01

    Alternative splicing (AS) is a fundamental process during gene expression and has been found to be ubiquitous in eukaryotes. However, how AS impacts gene expression levels both quantitatively and qualitatively remains to be fully explored. Here, we analyze two common models of gene expression, each incorporating a simple splice mechanism that a pre-mRNA is spliced into two mature mRNA isoforms in a probabilistic manner. In the constitutive expression case, we show that the steady-state molecular numbers of two mature mRNA isoforms follow mutually independent Poisson distributions. In the bursting expression case, we demonstrate that the tail decay of the steady-state distribution for both mature mRNA isoforms that in general are not mutually independent can be characterized by the product of mean burst size and splicing probability. In both cases, we find that AS can efficiently modulate both the variability (measured by variance) and the noise level of the total mature mRNA, and in particular, the latter is always lower than the noise level of the pre-mRNA, implying that AS always reduces the noise. These results altogether reveal that AS is a mechanism of efficiently controlling the gene expression noise.

  4. Gene Expression Analysis of HCT116 Colon Tumor-derived Cells Treated with the Polyamine Analog PG-11047

    PubMed Central

    IGNATENKO, NATALIA A.; YERUSHALMI, HAGIT F.; PANDEY, RITU; KACHEL, KAREN L.; STRINGER, DAVID E.; MARTON, LAURENCE J.; GERNER, EUGENE W.

    2013-01-01

    Background The conformationally restricted polyamine analog PG-11047 has significant growth inhibitory activity against prostate and lung cancer cell lines and is currently under evaluation in several clinical trials, both alone and in combination with other drugs, for the treatment of relapsed or refractory cancer. The objective of this study was to identify the molecular signature of genes responsive to PG-11047 treatment and the biochemical effects of this drug in the HCT116 colon cancer cell line. Materials and Methods Gene expression analysis was performed using Affymetrix GeneChip human genome U133 Plus 2.0 arrays. Changes in protein expression were evaluated using 2D polyacrylamide gels followed by LCMS/MS. Results Treatment of cells with PG-11047 at concentrations ranging from 0.1 to 10 μM caused inhibition of cell growth. The activity of PG-11047 was found to correlate with its transcriptional effects on cell cycle control, focal adhesion, adherent and gap junction genes, MAPK-, Wnt- and, TGF-β signaling pathways, transport and DNA/RNA transcription factor genes. PG-11047 caused depletion of polyamine pools. Proteomics analysis showed that PG-11047 restricts the modification of eukaryotic translation initiation factor 5A (eIF5A), resulting in suppression of general protein synthesis in PG-11047-treated cells. Conclusion These data show that PG-11047 has a broad spectrum of anticancer activity in colon cancer cells. PMID:19487545

  5. Validation and implementation of a method for microarray gene expression profiling of minor B-cell subpopulations in man

    PubMed Central

    2014-01-01

    Background This report describes a method for the generation of global gene expression profiles from low frequent B-cell subsets by using fluorescence-activated cell sorting and RNA amplification. However, some of the differentiating compartments involve a low number of cells and therefore it is important to optimize and validate each step in the procedure. Methods Normal lymphoid tissues from blood, tonsils, thymus and bone marrow were immunophenotyped by the 8-colour Euroflow panel using multiparametric flow cytometry. Subsets of B-cells containing cell numbers ranging from 800 to 33,000 and with frequencies varying between 0.1 and 10 percent were sorted, subjected to mRNA purification, amplified by the NuGEN protocol and finally analysed by the Affymetrix platform. Results Following a step by step strategy, each step in the workflow was validated and the sorting/storage conditions optimized as described in this report. First, an analysis of four cancer cell lines on Affymetrix arrays, using either 100 ng RNA labelled with the Ambion standard protocol or 1 ng RNA amplified and labelled by the NuGEN protocol, revealed a significant correlation of gene expressions (r ≥ 0.9 for all). Comparison of qPCR data in samples with or without amplification for 8 genes showed that a relative difference between six cell lines was preserved (r ≥ 0.9). Second, a comparison of cells sorted into PrepProtect, RNAlater or directly into lysis/binding buffer showed a higher yield of purified mRNA following storage in lysis/binding buffer (p < 0.001). Third, the identity of the B-cell subsets validated by the cluster of differentiation (CD) membrane profile was highly concordant with the transcriptional gene expression (p-values <0.001). Finally, in normal bone marrow and tonsil samples, eight evaluated genes were expressed in accordance with the biology of lymphopoiesis (p-values < 0.001), which enabled the generation of a gene-specific B-cell atlas. Conclusion A

  6. Gene expression variations during Drosophila metamorphosis in real and simulated gravity

    NASA Astrophysics Data System (ADS)

    Marco, R.; Leandro-García, L. J.; Benguría, A.; Herranz, R.; Zeballos, A.; Gassert, G.; van Loon, J. J.; Medina, F. J.

    Establishing the extent and significance of the effects of the exposure to microgravity of complex living organisms is a critical piece of information if the long-term exploration of near-by planets involving human beings is going to take place in the Future As a first step in this direction we have started to look into the patterns of gene expression during Drosophila development in real and simulated microgravity using microarray analysis of mRNA isolated from samples exposed to different environmental conditions In these experiments we used Affymetrix chips version 1 0 containing probes for more than 14 000 genes almost the complete Drosophila genome 55 of which are tagged with some molecular or functional designation while 45 are still waiting to be identified in functional terms The real microgravity exposure was imposed on the samples during the crew exchanging Soyuz 8 Mission to the ISS in October 2003 when after 11 days in Microgravity the Spanish-born astronaut Pedro Duque returned in the Soyuz 7 capsule carrying the experiments prepared by our Team Due to the constraints in the current ISS experiments in these Missions we limited the stages explored in our experiment to the developmental processes occurring during Drosophila metamorphosis As the experimental conditions at the launch site Baikonour were fairly limited we prepared the experiment in Madrid Toulouse and transp o rted the samples at 15 C in a temperature controlled container to slow down the developmental process a

  7. Effects of High Fat Feeding on Adipose Tissue Gene Expression in Diabetic Goto-Kakizaki Rats

    PubMed Central

    Xue, Bai; Nie, Jing; Wang, Xi; DuBois, Debra C; Jusko, William J; Almon, Richard R

    2015-01-01

    Development and progression of type 2 diabetes is a complex interaction between genetics and environmental influences. High dietary fat is one environmental factor that is conducive to the development of insulin-resistant diabetes. In the present report, we compare the responses of lean poly-genic, diabetic Goto-Kakizaki (GK) rats to those of control Wistar-Kyoto (WKY) rats fed a high fat diet from weaning to 20 weeks of age. This comparison included a wide array of physiological measurements along with gene expression profiling of abdominal adipose tissue using Affymetrix gene array chips. Animals of both strains fed a high fat diet or a normal diet were sacrificed at 4, 8, 12, 16, and 20 weeks for this comparison. The microarray analysis revealed that the two strains developed different adaptations to increased dietary fat. WKY rats decrease fatty acid synthesis and lipogenic processes whereas GK rats increase lipid elimination. However, on both diets the major differences between the two strains remained essentially the same. Specifically relative to the WKY strain, the GK strain showed lipoatrophy, chronic inflammation, and insulin resistance. PMID:26309393

  8. Dose response evaluation of gene expression profiles in the skin of K6/ODC mice exposed to sodium arsenite

    SciTech Connect

    Ahlborn, Gene J.; Nelson, Gail M.; Ward, William O.; Knapp, Geremy; Allen, James W.; Ouyang Ming; Roop, Barbara C.; Chen Yan; O'Brien, Thomas; Kitchin, Kirk T.; Delker, Don A.

    2008-03-15

    Chronic drinking water exposure to inorganic arsenic and its metabolites increases tumor frequency in the skin of K6/ODC transgenic mice. To identify potential biomarkers and modes of action for this skin tumorigenicity, we characterized gene expression profiles from analysis of K6/ODC mice administered 0, 0.05, 0.25, 1.0 and 10 ppm sodium arsenite in their drinking water for 4 weeks. Following exposure, total RNA was isolated from mouse skin and processed to biotin-labeled cRNA for microarray analyses. Skin gene expression was analyzed with Affymetrix Mouse Genome 430A 2.0 GeneChips (registered) , and pathway analysis was conducted with DAVID (NIH), Ingenuity (registered) Systems and MetaCore's GeneGo. Differential expression of several key genes was verified through qPCR. Only the highest dose (10 ppm) resulted in significantly altered KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including MAPK, regulation of actin cytoskeleton, Wnt, Jak-Stat, Tight junction, Toll-like, phosphatidylinositol and insulin signaling pathways. Approximately 20 genes exhibited a dose response, including several genes known to be associated with carcinogenesis or tumor progression including cyclin D1, CLIC4, Ephrin A1, STAT3 and DNA methyltransferase 3a. Although transcription changes in all identified genes have not previously been linked to arsenic carcinogenesis, their association with carcinogenesis in other systems suggests that these genes may play a role in the early stages of arsenic-induced skin carcinogenesis and can be considered potential biomarkers.

  9. Gene expression analysis of flax seed development

    PubMed Central

    2011-01-01

    Background Flax, Linum usitatissimum L., is an important crop whose seed oil and stem fiber have multiple industrial applications. Flax seeds are also well-known for their nutritional attributes, viz., omega-3 fatty acids in the oil and lignans and mucilage from the seed coat. In spite of the importance of this crop, there are few molecular resources that can be utilized toward improving seed traits. Here, we describe flax embryo and seed development and generation of comprehensive genomic resources for the flax seed. Results We describe a large-scale generation and analysis of expressed sequences in various tissues. Collectively, the 13 libraries we have used provide a broad representation of genes active in developing embryos (globular, heart, torpedo, cotyledon and mature stages) seed coats (globular and torpedo stages) and endosperm (pooled globular to torpedo stages) and genes expressed in flowers, etiolated seedlings, leaves, and stem tissue. A total of 261,272 expressed sequence tags (EST) (GenBank accessions LIBEST_026995 to LIBEST_027011) were generated. These EST libraries included transcription factor genes that are typically expressed at low levels, indicating that the depth is adequate for in silico expression analysis. Assembly of the ESTs resulted in 30,640 unigenes and 82% of these could be identified on the basis of homology to known and hypothetical genes from other plants. When compared with fully sequenced plant genomes, the flax unigenes resembled poplar and castor bean more than grape, sorghum, rice or Arabidopsis. Nearly one-fifth of these (5,152) had no homologs in sequences reported for any organism, suggesting that this category represents genes that are likely unique to flax. Digital analyses revealed gene expression dynamics for the biosynthesis of a number of important seed constituents during seed development. Conclusions We have developed a foundational database of expressed sequences and collection of plasmid clones that comprise

  10. Feline immunodeficiency virus OrfA alters gene expression of splicing factors and proteasome-ubiquitination proteins

    SciTech Connect

    Sundstrom, Magnus; Chatterji, Udayan; Schaffer, Lana; Rozieres, Sohela de; Elder, John H.

    2008-02-20

    Expression of the feline immunodeficiency virus (FIV) accessory protein OrfA (or Orf2) is critical for efficient viral replication in lymphocytes, both in vitro and in vivo. OrfA has been reported to exhibit functions in common with the human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) accessory proteins Vpr and Tat, although the function of OrfA has not been fully explained. Here, we use microarray analysis to characterize how OrfA modulates the gene expression profile of T-lymphocytes. The primary IL-2-dependent T-cell line 104-C1 was transduced to express OrfA. Functional expression of OrfA was demonstrated by trans complementation of the OrfA-defective clone, FIV-34TF10. OrfA-expressing cells had a slightly reduced cell proliferation rate but did not exhibit any significant alteration in cell cycle distribution. Reverse-transcribed RNA from cells expressing green fluorescent protein (GFP) or GFP + OrfA were hybridized to Affymetrix HU133 Plus 2.0 microarray chips representing more than 47,000 genome-wide transcripts. By using two statistical approaches, 461 (Rank Products) and 277 (ANOVA) genes were identified as modulated by OrfA expression. The functional relevance of the differentially expressed genes was explored by Ingenuity Pathway Analysis. The analyses revealed alterations in genes critical for RNA post-transcriptional modifications and protein ubiquitination as the two most significant functional outcomes of OrfA expression. In these two groups, several subunits of the spliceosome, cellular splicing factors and family members of the proteasome-ubiquitination system were identified. These findings provide novel information on the versatile function of OrfA during FIV infection and indicate a fine-tuning mechanism of the cellular environment by OrfA to facilitate efficient FIV replication.

  11. Inducible gene expression systems for plants.

    PubMed

    Borghi, Lorenzo

    2010-01-01

    Several systems for induction of transgene expression in plants have been described recently. Inducible systems were used mainly in tobacco, rice, Arabidopsis, tomato, and maize. Inducible systems offer researchers the possibility to deregulate gene expression levels at particular stages of plant development and in particular tissues of interest. The more precise temporal and spatial control, obtained by providing the transgenic plant with the appropriate chemical compound or treatment, permits to analyze also the function of those genes required for plant viability. In addition, inducible systems allow promoting local changes in gene expression levels without causing gross alterations to the whole plant development. Here, protocols will be presented to work with five different inducible systems: AlcR/AlcA (ethanol inducible); GR fusions, GVG, and pOp/LhGR (dexamethasone inducible); XVE/OlexA (beta-estradiol inducible); and heat shock induction. PMID:20734254

  12. The urologic epithelial stem cell database (UESC) – a web tool for cell type-specific gene expression and immunohistochemistry images of the prostate and bladder

    PubMed Central

    Pascal, Laura E; Deutsch, Eric W; Campbell, David S; Korb, Martin; True, Lawrence D; Liu, Alvin Y

    2007-01-01

    Background Public databases are crucial for analysis of high-dimensional gene and protein expression data. The Urologic Epithelial Stem Cells (UESC) database is a public database that contains gene and protein information for the major cell types of the prostate, prostate cancer cell lines, and a cancer cell type isolated from a primary tumor. Similarly, such information is available for urinary bladder cell types. Description Two major data types were archived in the database, protein abundance localization data from immunohistochemistry images, and transcript abundance data principally from DNA microarray analysis. Data results were organized in modules that were made to operate independently but built upon a core functionality. Gene array data and immunostaining images for human and mouse prostate and bladder were made available for interrogation. Data analysis capabilities include: (1) CD (cluster designation) cell surface protein data. For each cluster designation molecule, a data summary allows easy retrieval of images (at multiple magnifications). (2) Microarray data. Single gene or batch search can be initiated with Affymetrix Probeset ID, Gene Name, or Accession Number together with options of coalescing probesets and/or replicates. Conclusion Databases are invaluable for biomedical research, and their utility depends on data quality and user friendliness. UESC provides for database queries and tools to examine cell type-specific gene expression (normal vs. cancer), whereas most other databases contain only whole tissue expression datasets. The UESC database provides a valuable tool in the analysis of differential gene expression in prostate cancer genes in cancer progression. PMID:18072977

  13. Gene expression profiles in irradiated cancer cells

    NASA Astrophysics Data System (ADS)

    Minafra, L.; Bravatà, V.; Russo, G.; Ripamonti, M.; Gilardi, M. C.

    2013-07-01

    Knowledge of the molecular and genetic mechanisms underlying cellular response to radiation may provide new avenues to develop innovative predictive tests of radiosensitivity of tumours and normal tissues and to improve individual therapy. Nowadays very few studies describe molecular changes induced by hadrontherapy treatments, therefore this field has to be explored and clarified. High-throughput methodologies, such as DNA microarray, allow us to analyse mRNA expression of thousands of genes simultaneously in order to discover new genes and pathways as targets of response to hadrontherapy. Our aim is to elucidate the molecular networks involved in the sensitivity/resistance of cancer cell lines subjected to hadrontherapy treatments with a genomewide approach by using cDNA microarray technology to identify gene expression profiles and candidate genes responsible of differential cellular responses.

  14. Gene expression profiles in irradiated cancer cells

    SciTech Connect

    Minafra, L.; Bravatà, V.; Russo, G.; Ripamonti, M.; Gilardi, M. C.

    2013-07-26

    Knowledge of the molecular and genetic mechanisms underlying cellular response to radiation may provide new avenues to develop innovative predictive tests of radiosensitivity of tumours and normal tissues and to improve individual therapy. Nowadays very few studies describe molecular changes induced by hadrontherapy treatments, therefore this field has to be explored and clarified. High-throughput methodologies, such as DNA microarray, allow us to analyse mRNA expression of thousands of genes simultaneously in order to discover new genes and pathways as targets of response to hadrontherapy. Our aim is to elucidate the molecular networks involved in the sensitivity/resistance of cancer cell lines subjected to hadrontherapy treatments with a genomewide approach by using cDNA microarray technology to identify gene expression profiles and candidate genes responsible of differential cellular responses.

  15. Comparative gene expression profiling by oligonucleotide fingerprinting.

    PubMed Central

    Meier-Ewert, S; Lange, J; Gerst, H; Herwig, R; Schmitt, A; Freund, J; Elge, T; Mott, R; Herrmann, B; Lehrach, H

    1998-01-01

    The use of hybridisation of synthetic oligonucleotides to cDNAs under high stringency to characterise gene sequences has been demonstrated by a number of groups. We have used two cDNA libraries of 9 and 12 day mouse embryos (24 133 and 34 783 clones respectively) in a pilot study to characterise expressed genes by hybridisation with 110 hybridisation probes. We have identified 33 369 clusters of cDNA clones, that ranged in representation from 1 to 487 copies (0.7%). 737 were assigned to known rodent genes, and a further 13 845 showed significant homologies. A total of 404 clusters were identified as significantly differentially represented (P < 0.01) between the two cDNA libraries. This study demonstrates the utility of the fingerprinting approach for the generation of comparative gene expression profiles through the analysis of cDNAs derived from different biological materials. PMID:9547283

  16. Effect of Diet Supplementation on the Expression of Bovine Genes Associated with Fatty Acid Synthesis and Metabolism

    PubMed Central

    Joseph, Sandeep J.; Robbins, Kelly R.; Pavan, Enrique; Pratt, Scott L.; Duckett, Susan K.; Rekaya, Romdhane

    2010-01-01

    Conjugated linoleic acids (CLA) are of important nutritional and health benefit to human. Food products of animal origin are their major dietary source and their concentration increases with high concentrate diets fed to animals. To examine the effects of diet supplementation on the expression of genes related to lipid metabolism, 28 Angus steers were fed either pasture only, pasture with soybean hulls and corn oil, pasture with corn grain, or high concentrate diet. At slaughter, samples of subcutaneous adipose tissue were collected, from which RNA was extracted. Relative abundance of gene expression was measured using Affymetrix GeneChip Bovine Genome array. An ANOVA model nested within gene was used to analyze the background adjusted, normalized average difference of probe-level intensities. To control experiment wise error, a false discovery rate of 0.01 was imposed on all contrasts. Expression of several genes involved in the synthesis of enzymes related to fatty acid metabolism and lipogenesis such as stearoyl-CoA desaturase (SCD), fatty acid synthetase (FASN), lipoprotein lipase (LPL), fatty-acyl elongase (LCE) along with several trancription factors and co-activators involved in lipogenesis were found to be differentially expressed. Confirmatory RT-qPCR was done to validate the microarray results, which showed satisfactory correspondence between the two platforms. Results show that changes in diet by increasing dietary energy intake by supplementing high concentrate diet have effects on the transcription of genes encoding enzymes involved in fat metabolism which in turn has effects on fatty acid content in the carcass tissue as well as carcass quality. Corn supplementation either as oil or grain appeared to significantly alter the expression of genes directly associated with fatty acid synthesis. PMID:20448844

  17. Comparative analysis of gene expression profiles between cortex and thalamus in Chinese fatal familial insomnia patients.

    PubMed

    Tian, Chan; Liu, Di; Sun, Qing-Lan; Chen, Chen; Xu, Yin; Wang, Hui; Xiang, Wei; Kretzschmar, Hans A; Li, Wei; Chen, Cao; Shi, Qi; Gao, Chen; Zhang, Jin; Zhang, Bao-Yun; Han, Jun; Dong, Xiao-Ping

    2013-08-01

    Fatal familial insomnia (FFI) is a special subtype of genetic human prion diseases that is caused by the D178N mutation of the prion protein gene (PRNP). According to the surveillance data from 2006, FFI accounts for about half of all genetic prion disease cases in China. In this study, global expression patterns of the thalamus and parietal cortex from three patients with FFI were analyzed by Affymetrix Human Genome U133+ 2.0 chip. A total of 1,314 genes in the thalamus and 332 ones in the parietal lobe were determined to be differentially expressed genes (DEGs). The percentage of upregulated DEGs is much less in the thalamus (19.3 %) than that in the parietal lobe (42.8 %). Moreover, 255 of those DEGs showed the same altering tendencies in both tested regions, including 99 upregulated and 156 downregulated ones. The reliability of the results was confirmed by the real-time RT-PCR assays. There were 1,152 and 531 biological processes affected in the thalamus and the parietal lobe, respectively, as well as 391 overlapping ones in both regions. The most significantly changed molecular functions included transcription and DNA-dependent regulation of transcription, RNA splicing, mitochondrial electron transport, etc. The changed functions in the thalamus contained more numbers of DEGs than parietal lobe. According to KEGG classification, there were 167 and 115 different pathways changed in the thalamus and the parietal lobe, respectively, while 102 were changed in both. Interestingly, the top three changed pathways in the three groups mentioned above were Parkinson's disease, Alzheimer's disease, and oxidative phosphorylation. These results demonstrate the greater damage in the thalamus than in the parietal lobe during FFI pathogenesis, which is consistent with previous pathological observations. This study aims to describe the global expression profiles in various brain regions of FFI while proposing useful clues for understanding the pathogenesis of FFI and

  18. Visualizing Gene Expression In Situ

    SciTech Connect

    Burlage, R.S.

    1998-11-02

    Visualizing bacterial cells and describing their responses to the environment are difficult tasks. Their small size is the chief reason for the difficulty, which means that we must often use many millions of cells in a sample in order to determine what the average response of the bacteria is. However, an average response can sometimes mask important events in bacterial physiology, which means that our understanding of these organisms will suffer. We have used a variety of instruments to visualize bacterial cells, all of which tell us something different about the sample. We use a fluorescence activated cell sorter to sort cells based on the fluorescence provided by bioreporter genes, and these can be used to select for particular genetic mutations. Cells can be visualized by epifluorescent microscopy, and sensitive photodetectors can be added that allow us to find a single bacterial cell that is fluorescent or bioluminescent. We have also used standard photomultipliers to examine cell aggregates as field bioreporter microorganisms. Examples of each of these instruments show how our understanding of bacterial physiology has changed with the technology.

  19. Gene expression profile of Clonorchis sinensis metacercariae.

    PubMed

    Cho, Pyo Yun; Kim, Tae Im; Whang, Seong Man; Hong, Sung-Jong

    2008-01-01

    Clonorchis sinensis develop through miracidium, sporocyst, redia, cercaria, and metacercaria stages before becoming egg-laying adult flukes. The authors undertook this analysis of gene expression profiles during developmental stages to increase our understanding of the biology of C. sinensis and of host-parasite relationships. From a C. sinensis metacercariae complementary deoxyribonucleic acid library, 419 expressed sequence tags (ESTs) of average length of 668 bp were collected and assembled into 322 genes containing 70 clusters and 252 singletons. The genes were annotated using BLAST searches and categorized into ten major functional categories. Genes expressed abundantly were those of proteases and metabolic, transcription, and translation housekeeping proteins. Genes expressed higher in C. sinensis metacercariae than in adults coded structural and cytoskeletal proteins, transcription and translation machinery proteins, and energy metabolism-related proteins. This EST information supports the notion that C. sinensis metacercariae in fish hosts have a physiology and metabolism that is quite different from that of its adult form in mammals. PMID:17924144

  20. Type I Interferon–Inducible Gene Expression in Blood Is Present and Reflects Disease Activity in Dermatomyositis and Polymyositis

    PubMed Central

    Walsh, Ronan J.; Kong, Sek Won; Yao, Yihong; Jallal, Bahija; Kiener, Peter A.; Pinkus, Jack L.; Beggs, Alan H.; Amato, Anthony A.; Greenberg, Steven A.

    2008-01-01

    Objective To apply gene expression profiling to the study of peripheral blood mononuclear cells from patients with inflammatory myopathies, in order to provide insight into disease pathogenesis and identify potential biomarkers associated with disease activity. Methods We used Affymetrix whole-genome microarrays to measure the expression of ~38,500 genes in 65 blood and 15 muscle samples from 44 patients with dermatomyositis (DM), polymyositis (PM), inclusion body myositis (IBM), myasthenia gravis, or genetically determined myopathies and from 12 healthy volunteers. In 9 patients, 2 samples were obtained at different time points, when disease was either active or improving, and these paired blood samples were also compared. Bioinformatics techniques were used to identify genes with significant differential expression among diagnostic categories and in relation to disease activity. We corroborated the microarray data with quantitative real-time reverse transcriptase–polymerase chain reaction. Results Most patients with active DM or PM, but not patients with IBM, had significant and high up-regulation of the type I interferon-α/β (IFNα/β)–inducible genes in blood. Furthermore, the up-regulation of these genes correlated with disease activity in DM and PM, with down-regulation occurring when disease was controlled with treatment. Conclusion DM and PM are diseases characterized by the systemic overexpression of IFNα/β-inducible genes. The magnitude of the overexpression of these genes is higher in DM and correlates with disease activity in both disorders. Although PM and IBM have been modeled as having similar immunologic processes occurring within muscle, there are substantial differences in the expression of IFNα/β-inducible genes in blood in these diseases. PMID:17968926

  1. Optogenetics for gene expression in mammalian cells.

    PubMed

    Müller, Konrad; Naumann, Sebastian; Weber, Wilfried; Zurbriggen, Matias D

    2015-02-01

    Molecular switches that are controlled by chemicals have evolved as central research instruments in mammalian cell biology. However, these tools are limited in terms of their spatiotemporal resolution due to freely diffusing inducers. These limitations have recently been addressed by the development of optogenetic, genetically encoded, and light-responsive tools that can be controlled with the unprecedented spatiotemporal precision of light. In this article, we first provide a brief overview of currently available optogenetic tools that have been designed to control diverse cellular processes. Then, we focus on recent developments in light-controlled gene expression technologies and provide the reader with a guideline for choosing the most suitable gene expression system.

  2. Clustering of High Throughput Gene Expression Data

    PubMed Central

    Pirim, Harun; Ekşioğlu, Burak; Perkins, Andy; Yüceer, Çetin

    2012-01-01

    High throughput biological data need to be processed, analyzed, and interpreted to address problems in life sciences. Bioinformatics, computational biology, and systems biology deal with biological problems using computational methods. Clustering is one of the methods used to gain insight into biological processes, particularly at the genomics level. Clearly, clustering can be used in many areas of biological data analysis. However, this paper presents a review of the current clustering algorithms designed especially for analyzing gene expression data. It is also intended to introduce one of the main problems in bioinformatics - clustering gene expression data - to the operations research community. PMID:23144527

  3. Analysis of genomic aberrations and gene expression profiling identifies novel lesions and pathways in myeloproliferative neoplasms

    PubMed Central

    Rice, K L; Lin, X; Wolniak, K; Ebert, B L; Berkofsky-Fessler, W; Buzzai, M; Sun, Y; Xi, C; Elkin, P; Levine, R; Golub, T; Gilliland, D G; Crispino, J D; Licht, J D; Zhang, W

    2011-01-01

    Polycythemia vera (PV), essential thrombocythemia and primary myelofibrosis, are myeloproliferative neoplasms (MPNs) with distinct clinical features and are associated with the JAK2V617F mutation. To identify genomic anomalies involved in the pathogenesis of these disorders, we profiled 87 MPN patients using Affymetrix 250K single-nucleotide polymorphism (SNP) arrays. Aberrations affecting chr9 were the most frequently observed and included 9pLOH (n=16), trisomy 9 (n=6) and amplifications of 9p13.3–23.3 (n=1), 9q33.1–34.13 (n=1) and 9q34.13 (n=6). Patients with trisomy 9 were associated with elevated JAK2V617F mutant allele burden, suggesting that gain of chr9 represents an alternative mechanism for increasing JAK2V617F dosage. Gene expression profiling of patients with and without chr9 abnormalities (+9, 9pLOH), identified genes potentially involved in disease pathogenesis including JAK2, STAT5B and MAPK14. We also observed recurrent gains of 1p36.31–36.33 (n=6), 17q21.2–q21.31 (n=5) and 17q25.1–25.3 (n=5) and deletions affecting 18p11.31–11.32 (n=8). Combined SNP and gene expression analysis identified aberrations affecting components of a non-canonical PRC2 complex (EZH1, SUZ12 and JARID2) and genes comprising a ‘HSC signature' (MLLT3, SMARCA2 and PBX1). We show that NFIB, which is amplified in 7/87 MPN patients and upregulated in PV CD34+ cells, protects cells from apoptosis induced by cytokine withdrawal. PMID:22829077

  4. Analysis of genomic aberrations and gene expression profiling identifies novel lesions and pathways in myeloproliferative neoplasms.

    PubMed

    Rice, K L; Lin, X; Wolniak, K; Ebert, B L; Berkofsky-Fessler, W; Buzzai, M; Sun, Y; Xi, C; Elkin, P; Levine, R; Golub, T; Gilliland, D G; Crispino, J D; Licht, J D; Zhang, W

    2011-11-01

    Polycythemia vera (PV), essential thrombocythemia and primary myelofibrosis, are myeloproliferative neoplasms (MPNs) with distinct clinical features and are associated with the JAK2V617F mutation. To identify genomic anomalies involved in the pathogenesis of these disorders, we profiled 87 MPN patients using Affymetrix 250K single-nucleotide polymorphism (SNP) arrays. Aberrations affecting chr9 were the most frequently observed and included 9pLOH (n=16), trisomy 9 (n=6) and amplifications of 9p13.3-23.3 (n=1), 9q33.1-34.13 (n=1) and 9q34.13 (n=6). Patients with trisomy 9 were associated with elevated JAK2V617F mutant allele burden, suggesting that gain of chr9 represents an alternative mechanism for increasing JAK2V617F dosage. Gene expression profiling of patients with and without chr9 abnormalities (+9, 9pLOH), identified genes potentially involved in disease pathogenesis including JAK2, STAT5B and MAPK14. We also observed recurrent gains of 1p36.31-36.33 (n=6), 17q21.2-q21.31 (n=5) and 17q25.1-25.3 (n=5) and deletions affecting 18p11.31-11.32 (n=8). Combined SNP and gene expression analysis identified aberrations affecting components of a non-canonical PRC2 complex (EZH1, SUZ12 and JARID2) and genes comprising a 'HSC signature' (MLLT3, SMARCA2 and PBX1). We show that NFIB, which is amplified in 7/87 MPN patients and upregulated in PV CD34+ cells, protects cells from apoptosis induced by cytokine withdrawal.

  5. Genes Expressed in Human Tumor Endothelium

    NASA Astrophysics Data System (ADS)

    St. Croix, Brad; Rago, Carlo; Velculescu, Victor; Traverso, Giovanni; Romans, Katharine E.; Montgomery, Elizabeth; Lal, Anita; Riggins, Gregory J.; Lengauer, Christoph; Vogelstein, Bert; Kinzler, Kenneth W.

    2000-08-01

    To gain a molecular understanding of tumor angiogenesis, we compared gene expression patterns of endothelial cells derived from blood vessels of normal and malignant colorectal tissues. Of over 170 transcripts predominantly expressed in the endothelium, 79 were differentially expressed, including 46 that were specifically elevated in tumor-associated endothelium. Several of these genes encode extracellular matrix proteins, but most are of unknown function. Most of these tumor endothelial markers were expressed in a wide range of tumor types, as well as in normal vessels associated with wound healing and corpus luteum formation. These studies demonstrate that tumor and normal endothelium are distinct at the molecular level, a finding that may have significant implications for the development of anti-angiogenic therapies.

  6. Chromatin modifications remodel cardiac gene expression.

    PubMed

    Mathiyalagan, Prabhu; Keating, Samuel T; Du, Xiao-Jun; El-Osta, Assam

    2014-07-01

    Signalling and transcriptional control involve precise programmes of gene activation and suppression necessary for cardiovascular physiology. Deep sequencing of DNA-bound transcription factors reveals a remarkable complexity of co-activators or co-repressors that serve to alter chromatin modification and regulate gene expression. The regulated complexes characterized by genome-wide mapping implicate the recruitment and exchange of proteins with specific enzymatic activities that include roles for histone acetylation and methylation in key developmental programmes of the heart. As for transcriptional changes in response to pathological stress, co-regulatory complexes are also differentially utilized to regulate genes in cardiac disease. Members of the histone deacetylase (HDAC) family catalyse the removal of acetyl groups from proteins whose pharmacological inhibition has profound effects preventing heart failure. HDACs interact with a complex co-regulatory network of transcription factors, chromatin-remodelling complexes, and specific histone modifiers to regulate gene expression in the heart. For example, the histone methyltransferase (HMT), enhancer of zeste homolog 2 (Ezh2), is regulated by HDAC inhibition and associated with pathological cardiac hypertrophy. The challenge now is to target the activity of enzymes involved in protein modification to prevent or reverse the expression of genes implicated with cardiac hypertrophy. In this review, we discuss the role of HDACs and HMTs with a focus on chromatin modification and gene function as well as the clinical treatment of heart failure. PMID:24812277

  7. Sequence and gene expression evolution of paralogous genes in willows.

    PubMed

    Harikrishnan, Srilakshmy L; Pucholt, Pascal; Berlin, Sofia

    2015-12-22

    Whole genome duplications (WGD) have had strong impacts on species diversification by triggering evolutionary novelties, however, relatively little is known about the balance between gene loss and forces involved in the retention of duplicated genes originating from a WGD. We analyzed putative Salicoid duplicates in willows, originating from the Salicoid WGD, which took place more than 45 Mya. Contigs were constructed by de novo assembly of RNA-seq data derived from leaves and roots from two genotypes. Among the 48,508 contigs, 3,778 pairs were, based on fourfold synonymous third-codon transversion rates and syntenic positions, predicted to be Salicoid duplicates. Both copies were in most cases expressed in both tissues and 74% were significantly differentially expressed. Mean Ka/Ks was 0.23, suggesting that the Salicoid duplicates are evolving by purifying selection. Gene Ontology enrichment analyses showed that functions related to DNA- and nucleic acid binding were over-represented among the non-differentially expressed Salicoid duplicates, while functions related to biosynthesis and metabolism were over-represented among the differentially expressed Salicoid duplicates. We propose that the differentially expressed Salicoid duplicates are regulatory neo- and/or subfunctionalized, while the non-differentially expressed are dose sensitive, hence, functionally conserved. Multiple evolutionary processes, thus drive the retention of Salicoid duplicates in willows.

  8. Sequence and gene expression evolution of paralogous genes in willows

    PubMed Central

    Harikrishnan, Srilakshmy L.; Pucholt, Pascal; Berlin, Sofia

    2015-01-01

    Whole genome duplications (WGD) have had strong impacts on species diversification by triggering evolutionary novelties, however, relatively little is known about the balance between gene loss and forces involved in the retention of duplicated genes originating from a WGD. We analyzed putative Salicoid duplicates in willows, originating from the Salicoid WGD, which took place more than 45 Mya. Contigs were constructed by de novo assembly of RNA-seq data derived from leaves and roots from two genotypes. Among the 48,508 contigs, 3,778 pairs were, based on fourfold synonymous third-codon transversion rates and syntenic positions, predicted to be Salicoid duplicates. Both copies were in most cases expressed in both tissues and 74% were significantly differentially expressed. Mean Ka/Ks was 0.23, suggesting that the Salicoid duplicates are evolving by purifying selection. Gene Ontology enrichment analyses showed that functions related to DNA- and nucleic acid binding were over-represented among the non-differentially expressed Salicoid duplicates, while functions related to biosynthesis and metabolism were over-represented among the differentially expressed Salicoid duplicates. We propose that the differentially expressed Salicoid duplicates are regulatory neo- and/or subfunctionalized, while the non-differentially expressed are dose sensitive, hence, functionally conserved. Multiple evolutionary processes, thus drive the retention of Salicoid duplicates in willows. PMID:26689951

  9. Gene expression profiling analysis of ovarian cancer

    PubMed Central

    YIN, JI-GANG; LIU, XIAN-YING; WANG, BIN; WANG, DAN-YANG; WEI, MAN; FANG, HUA; XIANG, MEI

    2016-01-01

    As a gynecological oncology, ovarian cancer has high incidence and mortality. To study the mechanisms of ovarian cancer, the present study analyzed the GSE37582 microarray. GSE37582 was downloaded from Gene Expression Omnibus and included data from 74 ovarian cancer cases and 47 healthy controls. The differentially-expressed genes (DEGs) were screened using linear models for microarray data package in R and were further screened for functional annotation. Next, Gene Ontology and pathway enrichment analysis of the DEGs was conducted. The interaction associations of the proteins encoded by the DEGs were searched using the Search Tool for the Retrieval of Interacting Genes, and the protein-protein interaction (PPI) network was visualized by Cytoscape. Moreover, module analysis of the PPI network was performed using the BioNet analysis tool in R. A total of 284 DEGs were screened, consisting of 145 upregulated genes and 139 downregulated genes. In particular, downregulated FBJ murine osteosarcoma viral oncogene homolog (FOS) was an oncogene, while downregulated cyclin-dependent kinase inhibitor 1A (CDKN1A) was a tumor suppressor gene and upregulated cluster of differentiation 44 (CD44) was classed as an ‘other’ gene. The enriched functions included collagen catabolic process, stress-activated mitogen-activated protein kinases cascade and insulin receptor signaling pathway. Meanwhile, FOS (degree, 15), CD44 (degree, 9), B-cell CLL/lymphoma 2 (BCL2; degree, 7), CDKN1A (degree, 7) and matrix metallopeptidase 3 (MMP3; degree, 6) had higher connectivity degrees in the PPI network for the DEGs. These genes may be involved in ovarian cancer by interacting with other genes in the module of the PPI network (e.g., BCL2-FOS, BCL2-CDKN1A, FOS-CDKN1A, FOS-CD44, MMP3-MMP7 and MMP7-CD44). Overall, BCL2, FOS, CDKN1A, CD44, MMP3 and MMP7 may be correlated with ovarian cancer. PMID:27347159

  10. Negative energy balance alters global gene expression and immune responses in the uterus of postpartum dairy cows.

    PubMed

    Wathes, D Claire; Cheng, Zhangrui; Chowdhury, Waliul; Fenwick, Mark A; Fitzpatrick, Richard; Morris, Dermot G; Patton, Joe; Murphy, John J

    2009-09-01

    Most dairy cows suffer uterine microbial contamination postpartum. Persistent endometritis often develops, associated with reduced fertility. We used a model of differential feeding and milking regimes to produce cows in differing negative energy balance status in early lactation (mild or severe, MNEB or SNEB). Blood hematology was assessed preslaughter at 2 wk postpartum. RNA expression in endometrial samples was compared using bovine Affymetrix arrays. Data were mapped using Ingenuity Pathway Analysis. Circulating concentrations of IGF-I remained lower in the SNEB group, whereas blood nonesterified fatty acid and beta-hydroxybutyrate concentrations were raised. White blood cell count and lymphocyte number were reduced in SNEB cows. Array analysis of endometrial samples identified 274 differentially expressed probes representing 197 recognized genes between the energy balance groups. The main canonical pathways affected related to immunological and inflammatory disease and connective tissue disorders. Inflammatory response genes with major upregulation in SNEB cows included matrix metalloproteinases, chemokines, cytokines, and calgranulins. Expression of several interferon-inducible genes including ISG20, IFIH1, MX1, and MX2 were also significantly increased in the SNEB cows. These results provide evidence that cows in SNEB were still undergoing an active uterine inflammatory response 2 wk postpartum, whereas MNEB cows had more fully recovered from their energy deficit, with their endometrium reaching a more advanced stage of repair. SNEB may therefore prevent cows from mounting an effective immune response to the microbial challenge experienced after calving, prolonging the time required for uterine recovery and compromising subsequent fertility.

  11. Gene expression profiles in peripheral blood mononuclear cells of Chinese nickel refinery workers with high exposures to nickel and control subjects

    PubMed Central

    Arita, Adriana; Muñoz, Alexandra; Chervona, Yana; Niu, Jingping; Qu, Qingshan; Zhao, Najuan; Ruan, Ye; Kiok, Kathrin; Kluz, Thomas; Sun, Hong; Clancy, Hailey A.; Shamy, Magdy; Costa, Max

    2012-01-01

    Background Occupational exposure to nickel (Ni) is associated with an increased risk of lung and nasal cancers. Ni compounds exhibit weak mutagenic activity, alter the cell’s epigenetic homeostasis, and activate signaling pathways. However, changes in gene expression associated with Ni exposure have only been investigated in vitro. This study was conducted in a Chinese population to determine whether occupational exposure to Ni was associated with differential gene expression profiles in the peripheral blood mononuclear cells (PBMCs) of Ni-refinery workers when compared to referents. Methods Eight Ni-refinery workers and ten referents were selected. PBMC RNA was extracted and gene expression profiling was performed using Affymetrix exon arrays. Differentially expressed genes between both groups were identified in a global analysis. Results There were a total of 2756 differentially expressed genes (DEG) in the Ni-refinery workers relative to the control subjects (FDR adjusted p<0.05) with 770 up-regulated genes and 1986 down-regulated genes. DNA repair and epigenetic genes were significantly overrepresented (p< 0.0002) among the DEG. Of 31 DNA repair genes, 29 were repressed in the high exposure group and two were overexpressed. Of the 16 epigenetic genes 12 were repressed in the high exposure group and 4 were overexpressed. Conclusions The results of this study indicate that occupational exposure to Ni is associated with alterations in gene expression profiles in PBMCs of subjects. Impact Gene expression may be useful in identifying patterns of deregulation that precede clinical identification of Ni-induced cancers. PMID:23195993

  12. Sex-specific patterns and deregulation of endocrine pathways in the gene expression profiles of Bangladeshi adults exposed to arsenic contaminated drinking water

    SciTech Connect

    Muñoz, Alexandra; Chervona, Yana; Hall, Megan; Kluz, Thomas; Gamble, Mary V.; Costa, Max

    2015-05-01

    Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung and bladder cancers, and cardiovascular disease. Recent research indicates that arsenic may be an endocrine disruptor. This study was conducted to evaluate the nature of gene expression changes among males and females exposed to arsenic contaminated water in Bangladesh at high and low doses. Twenty-nine (55% male) Bangladeshi adults with water arsenic exposure ranging from 50 to 1000 μg/L were selected from the Folic Acid Creatinine Trial. RNA was extracted from peripheral blood mononuclear cells for gene expression profiling using Affymetrix 1.0 ST arrays. Differentially expressed genes were assessed between high and low exposure groups for males and females separately and findings were validated using quantitative real-time PCR. There were 534 and 645 differentially expressed genes (p < 0.05) in the peripheral blood mononuclear cells of males and females, respectively, when high and low water arsenic exposure groups were compared. Only 43 genes overlapped between the two sexes, with 29 changing in opposite directions. Despite the difference in gene sets both males and females exhibited common biological changes including deregulation of 17β-hydroxysteroid dehydrogenase enzymes, deregulation of genes downstream of Sp1 (specificity protein 1) transcription factor, and prediction of estrogen receptor alpha as a key hub in cardiovascular networks. Arsenic-exposed adults exhibit sex-specific gene expression profiles that implicate involvement of the endocrine system. Due to arsenic's possible role as an endocrine disruptor, exposure thresholds for arsenic may require different parameters for males and females. - Highlights: • Males and females exhibit unique gene expression changes in response to arsenic. • Only 23 genes are common among the differentially expressed genes for the sexes. • Male and female gene lists exhibit common biological

  13. In vitro gene expression data supporting a DNA non-reactive genotoxic mechanism for ochratoxin A

    SciTech Connect

    Arbillaga, Leire; Lopez de Cerain, Adela . E-mail: acerain@unav.es

    2007-04-15

    Ochratoxin A (OTA) is a mycotoxin often found in cereals and agricultural products. There is unequivocal evidence of renal carcinogenicity of OTA in male rats, although the mechanism of action is unknown. At present, available data support an epigenetic mechanism (DNA non-reactive) resulting from oxidative stress and cytotoxicity, because a direct OTA interaction with DNA has not been demonstrated. Genotoxic mechanism (DNA-reactive vs. DNA non-reactive) may have implications on human risk assessment. Therefore, the aim of the present work was to identify biological pathways modulated by OTA in vitro in a human renal cell line (HK-2) to contribute to the elucidation of the mechanism of OTA toxicity. For that purpose, cells were exposed to 50 {mu}M OTA during 6 and 24 h, and gene expression profiles were analyzed using Affymetrix Human Genome U133 A 2.0 Gene Chips. Under the same experimental conditions, genotoxicity was evaluated by the modified comet assay using FPG and Endo III to detect oxidative DNA damage, and intracellular ROS level by the H{sub 2}DCF assay. After 6 h, with slight cytotoxicity (83% survival), genes involved in mitochondrial electron transport chain were up-regulated; and after 24 h, with a more pronounced cytotoxicity (51% survival), genes implicated in oxidative stress response were also up-regulated. Increase in intracellular ROS level and oxidative DNA damage was evident at both exposure times being more pronounced with high cytotoxicity. On the contrary, up-regulation of genes implicated in DNA damage response, as cell cycle control or apoptosis, was not detected at any exposure time. In conclusion, these results support a DNA non-reactive mechanism of OTA genotoxicity.

  14. Global Gene Expression Profiling and Alternative Splicing Events during the Chondrogenic Differentiation of Human Cartilage Endplate-Derived Stem Cells

    PubMed Central

    Shang, Jin; Fan, Xin; Shangguan, Lei; Liu, Huan; Zhou, Yue

    2015-01-01

    Low back pain (LBP) is a very prevalent disease and degenerative disc diseases (DDDs) usually account for the LBP. However, the pathogenesis of DDDs is complicated and difficult to elucidate. Alternative splicing is a sophisticated regulatory process which greatly increases cellular complexity and phenotypic diversity of eukaryotic organisms. In addition, the cartilage endplate-derived stem cells have been discovered and identified by our research group. In this paper, we continue to investigate gene expression profiling and alternative splicing events during chondrogenic differentiation of cartilage endplate-derived stem cells. We adopted Affymetrix Human Transcriptome Array 2.0 (HTA 2.0) to compare the transcriptional and splicing changes between the control and differentiated samples. RT-PCR and quantitative PCR are used to validate the microarray results. The GO and KEGG pathway analysis was also performed. After bioinformatics analysis of the data, we detected 1953 differentially expressed genes. In terms of alternative splicing, the Splicing Index algorithm was used to select alternatively spliced genes. We detected 4411 alternatively spliced genes. GO and KEGG pathway analysis also revealed several functionally involved biological processes and signaling pathways. To our knowledge, this is the first study to investigate the alternative splicing mechanisms in chondrogenic differentiation of stem cells on a genome-wide scale. PMID:26649308

  15. Tissue-specific patterns of gene expression in the epithelium and stroma of normal colon in healthy individuals in an aspirin intervention trial.

    PubMed

    Thomas, Sushma S; Makar, Karen W; Li, Lin; Zheng, Yingye; Yang, Peiying; Levy, Lisa; Rudolph, Rebecca Y; Lampe, Paul D; Yan, Min; Markowitz, Sanford D; Bigler, Jeannette; Lampe, Johanna W; Potter, John D

    2015-12-01

    Regular aspirin use reduces colon adenoma and carcinoma incidence. UDP-glucuronosyltransferases (UGT) are involved in aspirin metabolism and clearance, and variant alleles in UGT1A6 have been shown to alter salicylic acid metabolism and risk of colon neoplasia. In a randomized, cross-over, placebo-controlled trial of 44 healthy men and women, homozygous for UGT1A6*1 or UGT1A6*2, we explored differences between global epithelial and stromal expression, using Affymetrix U133 + 2.0 microarrays and tested effects of 60-day aspirin supplementation (325 mg/d) on epithelial and stromal gene expression and colon prostaglandin E2 (PGE2) levels. We conducted a comprehensive study of differential gene expression between normal human colonic epithelium and stroma from healthy individuals. Although no statistically significant differences in gene expression were observed in response to aspirin or UGT1A6 genotype, we have identified the genes uniquely and reproducibly expressed in each tissue type and have analyzed the biologic processes they represent. Here we describe in detail how the data, deposited in the Gene Expression Omnibus (GEO) - accession number GSE71571 - was generated including the basic analysis as contained in the manuscript published in BMC Medical Genetics with the PMID 25927723 (Thomas et al., 2015 [9]).

  16. Tissue-specific patterns of gene expression in the epithelium and stroma of normal colon in healthy individuals in an aspirin intervention trial

    PubMed Central

    Thomas, Sushma S.; Makar, Karen W.; Li, Lin; Zheng, Yingye; Yang, Peiying; Levy, Lisa; Rudolph, Rebecca Y.; Lampe, Paul D.; Yan, Min; Markowitz, Sanford D.; Bigler, Jeannette; Lampe, Johanna W.; Potter, John D.

    2015-01-01

    Regular aspirin use reduces colon adenoma and carcinoma incidence. UDP-glucuronosyltransferases (UGT) are involved in aspirin metabolism and clearance, and variant alleles in UGT1A6 have been shown to alter salicylic acid metabolism and risk of colon neoplasia. In a randomized, cross-over, placebo-controlled trial of 44 healthy men and women, homozygous for UGT1A6*1 or UGT1A6*2, we explored differences between global epithelial and stromal expression, using Affymetrix U133 + 2.0 microarrays and tested effects of 60-day aspirin supplementation (325 mg/d) on epithelial and stromal gene expression and colon prostaglandin E2 (PGE2) levels. We conducted a comprehensive study of differential gene expression between normal human colonic epithelium and stroma from healthy individuals. Although no statistically significant differences in gene expression were observed in response to aspirin or UGT1A6 genotype, we have identified the genes uniquely and reproducibly expressed in each tissue type and have analyzed the biologic processes they represent. Here we describe in detail how the data, deposited in the Gene Expression Omnibus (GEO) – accession number GSE71571 – was generated including the basic analysis as contained in the manuscript published in BMC Medical Genetics with the PMID 25927723 (Thomas et al., 2015 [9]). PMID:26697360

  17. Gene expression profiling of human erythroid progenitors by micro-serial analysis of gene expression.

    PubMed

    Fujishima, Naohito; Hirokawa, Makoto; Aiba, Namiko; Ichikawa, Yoshikazu; Fujishima, Masumi; Komatsuda, Atsushi; Suzuki, Yoshiko; Kawabata, Yoshinari; Miura, Ikuo; Sawada, Ken-ichi

    2004-10-01

    We compared the expression profiles of highly purified human CD34+ cells and erythroid progenitor cells by micro-serial analysis of gene expression (microSAGE). Human CD34+ cells were purified from granulocyte colony-stimulating factor-mobilized blood stem cells, and erythroid progenitors were obtained by cultivating these cells in the presence of stem cell factor, interleukin 3, and erythropoietin. Our 10,202 SAGE tags allowed us to identify 1354 different transcripts appearing more than once. Erythroid progenitor cells showed increased expression of LRBA, EEF1A1, HSPCA, PILRB, RANBP1, NACA, and SMURF. Overexpression of HSPCA was confirmed by real-time polymerase chain reaction analysis. MicroSAGE revealed an unexpected preferential expression of several genes in erythroid progenitor cells in addition to the known functional genes, including hemoglobins. Our results provide reference data for future studies of gene expression in various hematopoietic disorders, including myelodysplastic syndrome and leukemia.

  18. The low noise limit in gene expression

    SciTech Connect

    Dar, Roy D.; Weinberger, Leor S.; Cox, Chris D.; Simpson, Michael L.; Razooky, Brandon S.

    2015-10-21

    Protein noise measurements are increasingly used to elucidate biophysical parameters. Unfortunately noise analyses are often at odds with directly measured parameters. Here we show that these inconsistencies arise from two problematic analytical choices: (i) the assumption that protein translation rate is invariant for different proteins of different abundances, which has inadvertently led to (ii) the assumption that a large constitutive extrinsic noise sets the low noise limit in gene expression. While growing evidence suggests that transcriptional bursting may set the low noise limit, variability in translational bursting has been largely ignored. We show that genome-wide systematic variation in translational efficiency can-and in the case of E. coli does-control the low noise limit in gene expression. Therefore constitutive extrinsic noise is small and only plays a role in the absence of a systematic variation in translational efficiency. Lastly, these results show the existence of two distinct expression noise patterns: (1) a global noise floor uniformly imposed on all genes by expression bursting; and (2) high noise distributed to only a select group of genes.

  19. The low noise limit in gene expression

    DOE PAGES

    Dar, Roy D.; Weinberger, Leor S.; Cox, Chris D.; Simpson, Michael L.; Razooky, Brandon S.

    2015-10-21

    Protein noise measurements are increasingly used to elucidate biophysical parameters. Unfortunately noise analyses are often at odds with directly measured parameters. Here we show that these inconsistencies arise from two problematic analytical choices: (i) the assumption that protein translation rate is invariant for different proteins of different abundances, which has inadvertently led to (ii) the assumption that a large constitutive extrinsic noise sets the low noise limit in gene expression. While growing evidence suggests that transcriptional bursting may set the low noise limit, variability in translational bursting has been largely ignored. We show that genome-wide systematic variation in translational efficiencymore » can-and in the case of E. coli does-control the low noise limit in gene expression. Therefore constitutive extrinsic noise is small and only plays a role in the absence of a systematic variation in translational efficiency. Lastly, these results show the existence of two distinct expression noise patterns: (1) a global noise floor uniformly imposed on all genes by expression bursting; and (2) high noise distributed to only a select group of genes.« less

  20. Trigger finger, tendinosis, and intratendinous gene expression.

    PubMed

    Lundin, A-C; Aspenberg, P; Eliasson, P

    2014-04-01

    The pathogenesis of trigger finger has generally been ascribed to primary changes in the first annular ligament. In contrast, we recently found histological changes in the tendons, similar to the findings in Achilles tendinosis or tendinopathy. We therefore hypothesized that trigger finger tendons would show differences in gene expression in comparison to normal tendons in a pattern similar to what is published for Achilles tendinosis. We performed quantitative real-time polymerase chain reaction on biopsies from finger flexor tendons, 13 trigger fingers and 13 apparently healthy control tendons, to assess the expression of 10 genes which have been described to be differently expressed in tendinosis (collagen type 1a1, collagen 3a1, MMP-2, MMP-3, ADAMTS-5, TIMP-3, aggrecan, biglycan, decorin, and versican). In trigger finger tendons, collagen types 1a1 and 3a1, aggrecan and biglycan were all up-regulated, and MMP-3and TIMP-3 were down-regulated. These changes were statistically significant and have been previously described for Achilles tendinosis. The remaining four genes were not significantly altered. The changes in gene expression support the hypothesis that trigger finger is a form of tendinosis. Because trigger finger is a common condition, often treated surgically, it could provide opportunities for clinical research on tendinosis. PMID:22882155

  1. Multiple Stochastic Point Processes in Gene Expression

    NASA Astrophysics Data System (ADS)

    Murugan, Rajamanickam

    2008-04-01

    We generalize the idea of multiple-stochasticity in chemical reaction systems to gene expression. Using Chemical Langevin Equation approach we investigate how this multiple-stochasticity can influence the overall molecular number fluctuations. We show that the main sources of this multiple-stochasticity in gene expression could be the randomness in transcription and translation initiation times which in turn originates from the underlying bio-macromolecular recognition processes such as the site-specific DNA-protein interactions and therefore can be internally regulated by the supra-molecular structural factors such as the condensation/super-coiling of DNA. Our theory predicts that (1) in case of gene expression system, the variances ( φ) introduced by the randomness in transcription and translation initiation-times approximately scales with the degree of condensation ( s) of DNA or mRNA as φ ∝ s -6. From the theoretical analysis of the Fano factor as well as coefficient of variation associated with the protein number fluctuations we predict that (2) unlike the singly-stochastic case where the Fano factor has been shown to be a monotonous function of translation rate, in case of multiple-stochastic gene expression the Fano factor is a turn over function with a definite minimum. This in turn suggests that the multiple-stochastic processes can also be well tuned to behave like a singly-stochastic point processes by adjusting the rate parameters.

  2. Population-level control of gene expression

    NASA Astrophysics Data System (ADS)

    Nevozhay, Dmitry; Adams, Rhys; van Itallie, Elizabeth; Bennett, Matthew; Balazsi, Gabor

    2011-03-01

    Gene expression is the process that translates genetic information into proteins, that determine the way cells live, function and even die. It was demonstrated that cells with identical genomes exposed to the same environment can differ in their protein composition and therefore phenotypes. Protein levels can vary between cells due to the stochastic nature of intracellular biochemical events, indicating that the genotype-phenotype connection is not deterministic at the cellular level. We asked whether genomes could encode isogenic cell populations more reliably than single cells. To address this question, we built two gene circuits to control three cell population-level characteristics: gene expression mean, coefficient of variation and non-genetic memory of previous expression states. Indeed, we found that these population-level characteristics were more predictable than the gene expression of single cells in a well-controlled environment. This research was supported by the NIH Director's New Innovator Award 1DP2 OD006481-01 and Welch Foundation Grant C-1729.

  3. Expression of mouse metallothionein genes in tobacco

    SciTech Connect

    Maiti, I.B.; Yeargan, R.; Wagner, G.J.; Hunt, A.G. )

    1990-05-01

    We have expressed a mouse metallothionein (NT) gene in tobacco under control of the cauliflower mosaic virus (CaMV) 35S promoter and a pea ribulose-1,5-bisphosphate carboxylase small subunit (rbcS) gene promoter. Seedlings in which MT gene expression is driven by the 35S promoter are resistant to toxic levels of cadmium. Mature plants carrying the 35S-MT gene accumulate less Cd in their leaves when exposed to low levels of Cd in laboratory growth conditions. Plants with the rbcS-MT construction express this gene in a light-regulated and tissue-specific manner, as expected. Moreover, the MT levels in leaves in these plants are about 20% of those seen in 35S-MT plants. These plants are currently being tested for Cd resistance. In addition, a small field evaluation of 35S-MT lines for Cd levels is being evaluated. These experiments will address the possibility of using MTs to alter Cd levels in crop species.

  4. Functionalization of a protosynaptic gene expression network

    PubMed Central

    Conaco, Cecilia; Bassett, Danielle S.; Zhou, Hongjun; Arcila, Mary Luz; Degnan, Sandie M.; Degnan, Bernard M.; Kosik, Kenneth S.

    2012-01-01

    Assembly of a functioning neuronal synapse requires the precisely coordinated synthesis of many proteins. To understand the evolution of this complex cellular machine, we tracked the developmental expression patterns of a core set of conserved synaptic genes across a representative sampling of the animal kingdom. Coregulation, as measured by correlation of gene expression over development, showed a marked increase as functional nervous systems emerged. In the earliest branching animal phyla (Porifera), in which a nearly complete set of synaptic genes exists in the absence of morphological synapses, these “protosynaptic” genes displayed a lack of global coregulation although small modules of coexpressed genes are readily detectable by using network analysis techniques. These findings suggest that functional synapses evolved by exapting preexisting cellular machines, likely through some modification of regulatory circuitry. Evolutionarily ancient modules continue to operate seamlessly within the synapses of modern animals. This work shows that the application of network techniques to emerging genomic and expression data can provide insights into the evolution of complex cellular machines such as the synapse. PMID:22723359

  5. Coordination of plastid and nuclear gene expression.

    PubMed Central

    Gray, John C; Sullivan, James A; Wang, Jun-Hui; Jerome, Cheryl A; MacLean, Daniel

    2003-01-01

    The coordinated expression of genes distributed between the nuclear and plastid genomes is essential for the assembly of functional chloroplasts. Although the nucleus has a pre-eminent role in controlling chloroplast biogenesis, there is considerable evidence that the expression of nuclear genes encoding photosynthesis-related proteins is regulated by signals from plastids. Perturbation of several plastid-located processes, by inhibitors or in mutants, leads to decreased transcription of a set of nuclear photosynthesis-related genes. Characterization of arabidopsis gun (genomes uncoupled) mutants, which express nuclear genes in the presence of norflurazon or lincomycin, has provided evidence for two separate signalling pathways, one involving tetrapyrrole biosynthesis intermediates and the other requiring plastid protein synthesis. In addition, perturbation of photosynthetic electron transfer produces at least two different redox signals, as part of the acclimation to altered light conditions. The recognition of multiple plastid signals requires a reconsideration of the mechanisms of regulation of transcription of nuclear genes encoding photosynthesis-related proteins. PMID:12594922

  6. The Affymetrix DMET Plus Platform Reveals Unique Distribution of ADME-Related Variants in Ethnic Arabs

    PubMed Central

    Wakil, Salma M.; Nguyen, Cao; Muiya, Nzioka P.; Andres, Editha; Lykowska-Tarnowska, Agnieszka; Baz, Batoul; Meyer, Brian F.; Morahan, Grant

    2015-01-01

    Background. The Affymetrix Drug Metabolizing Enzymes and Transporters (DMET) Plus Premier Pack has been designed to genotype 1936 gene variants thought to be essential for screening patients in personalized drug therapy. These variants include the cytochrome P450s (CYP450s), the key metabolizing enzymes, many other enzymes involved in phase I and phase II pharmacokinetic reactions, and signaling mediators associated with variability in clinical response to numerous drugs not only among individuals, but also between ethnic populations. Materials and Methods. We genotyped 600 Saudi individuals for 1936 variants on the DMET platform to evaluate their clinical potential in personalized medicine in ethnic Arabs. Results. Approximately 49% each of the 437 CYP450 variants, 56% of the 581 transporters, 56% of 419 transferases, 48% of the 104 dehydrogenases, and 58% of the remaining 390 variants were detected. Several variants, such as rs3740071, rs6193, rs258751, rs6199, rs11568421, and rs8187797, exhibited significantly either higher or lower minor allele frequencies (MAFs) than those in other ethnic groups. Discussion. The present study revealed some unique distribution trends for several variants in Arabs, which displayed partly inverse allelic prevalence compared to other ethnic populations. The results point therefore to the need to verify and ascertain the prevalence of a variant as a prerequisite for engaging it in clinical routine screening in personalized medicine in any given population. PMID:25802476

  7. Gene Expression Commons: An Open Platform for Absolute Gene Expression Profiling

    PubMed Central

    Seita, Jun; Sahoo, Debashis; Rossi, Derrick J.; Bhattacharya, Deepta; Serwold, Thomas; Inlay, Matthew A.; Ehrlich, Lauren I. R.; Fathman, John W.; Dill, David L.; Weissman, Irving L.

    2012-01-01

    Gene expression profiling using microarrays has been limited to comparisons of gene expression between small numbers of samples within individual experiments. However, the unknown and variable sensitivities of each probeset have rendered the absolute expression of any given gene nearly impossible to estimate. We have overcome this limitation by using a very large number (>10,000) of varied microarray data as a common reference, so that statistical attributes of each probeset, such as the dynamic range and threshold between low and high expression, can be reliably discovered through meta-analysis. This strategy is implemented in a web-based platform named “Gene Expression Commons” (https://gexc.stanford.edu/) which contains data of 39 distinct highly purified mouse hematopoietic stem/progenitor/differentiated cell populations covering almost the entire hematopoietic system. Since the Gene Expression Commons is designed as an open platform, investigators can explore the expression level of any gene, search by expression patterns of interest, submit their own microarray data, and design their own working models representing biological relationship among samples. PMID:22815738

  8. Regulation of methane genes and genome expression

    SciTech Connect

    John N. Reeve

    2009-09-09

    At the start of this project, it was known that methanogens were Archaeabacteria (now Archaea) and were therefore predicted to have gene expression and regulatory systems different from Bacteria, but few of the molecular biology details were established. The goals were then to establish the structures and organizations of genes in methanogens, and to develop the genetic technologies needed to investigate and dissect methanogen gene expression and regulation in vivo. By cloning and sequencing, we established the gene and operon structures of all of the “methane” genes that encode the enzymes that catalyze methane biosynthesis from carbon dioxide and hydrogen. This work identified unique sequences in the methane gene that we designated mcrA, that encodes the largest subunit of methyl-coenzyme M reductase, that could be used to identify methanogen DNA and establish methanogen phylogenetic relationships. McrA sequences are now the accepted standard and used extensively as hybridization probes to identify and quantify methanogens in environmental research. With the methane genes in hand, we used northern blot and then later whole-genome microarray hybridization analyses to establish how growth phase and substrate availability regulated methane gene expression in Methanobacterium thermautotrophicus ΔH (now Methanothermobacter thermautotrophicus). Isoenzymes or pairs of functionally equivalent enzymes catalyze several steps in the hydrogen-dependent reduction of carbon dioxide to methane. We established that hydrogen availability determine which of these pairs of methane genes is expressed and therefore which of the alternative enzymes is employed to catalyze methane biosynthesis under different environmental conditions. As were unable to establish a reliable genetic system for M. thermautotrophicus, we developed in vitro transcription as an alternative system to investigate methanogen gene expression and regulation. This led to the discovery that an archaeal protein

  9. Fluid Mechanics, Arterial Disease, and Gene Expression

    NASA Astrophysics Data System (ADS)

    Tarbell, John M.; Shi, Zhong-Dong; Dunn, Jessilyn; Jo, Hanjoong

    2014-01-01

    This review places modern research developments in vascular mechanobiology in the context of hemodynamic phenomena in the cardiovascular system and the discrete localization of vascular disease. The modern origins of this field are traced, beginning in the 1960s when associations between flow characteristics, particularly blood flow-induced wall shear stress, and the localization of atherosclerotic plaques were uncovered, and continuing to fluid shear stress effects on the vascular lining endothelial cells (ECs), including their effects on EC morphology, biochemical production, and gene expression. The earliest single-gene studies and genome-wide analyses are considered. The final section moves from the ECs lining the vessel wall to the smooth muscle cells and fibroblasts within the wall that are fluid mechanically activated by interstitial flow that imposes shear stresses on their surfaces comparable with those of flowing blood on EC surfaces. Interstitial flow stimulates biochemical production and gene expression, much like blood flow on ECs.

  10. Fluid Mechanics, Arterial Disease, and Gene Expression

    PubMed Central

    Tarbell, John M.; Shi, Zhong-Dong; Dunn, Jessilyn; Jo, Hanjoong

    2014-01-01

    This review places modern research developments in vascular mechanobiology in the context of hemodynamic phenomena in the cardiovascular system and the discrete localization of vascular disease. The modern origins of this field are traced, beginning in the 1960s when associations between flow characteristics, particularly blood flow–induced wall shear stress, and the localization of atherosclerotic plaques were uncovered, and continuing to fluid shear stress effects on the vascular lining endothelial) cells (ECs), including their effects on EC morphology, biochemical production, and gene expression. The earliest single-gene studies and genome-wide analyses are considered. The final section moves from the ECs lining the vessel wall to the smooth muscle cells and fibroblasts within the wall that are fluid me chanically activated by interstitial flow that imposes shear stresses on their surfaces comparable with those of flowing blood on EC surfaces. Interstitial flow stimulates biochemical production and gene expression, much like blood flow on ECs. PMID:25360054

  11. Fluid Mechanics, Arterial Disease, and Gene Expression.

    PubMed

    Tarbell, John M; Shi, Zhong-Dong; Dunn, Jessilyn; Jo, Hanjoong

    2014-01-01

    This review places modern research developments in vascular mechanobiology in the context of hemodynamic phenomena in the cardiovascular system and the discrete localization of vascular disease. The modern origins of this field are traced, beginning in the 1960s when associations between flow characteristics, particularly blood flow-induced wall shear stress, and the localization of atherosclerotic plaques were uncovered, and continuing to fluid shear stress effects on the vascular lining endothelial) cells (ECs), including their effects on EC morphology, biochemical production, and gene expression. The earliest single-gene studies and genome-wide analyses are considered. The final section moves from the ECs lining the vessel wall to the smooth muscle cells and fibroblasts within the wall that are fluid me chanically activated by interstitial flow that imposes shear stresses on their surfaces comparable with those of flowing blood on EC surfaces. Interstitial flow stimulates biochemical production and gene expression, much like blood flow on ECs.

  12. Control mechanisms of plastid gene expression

    SciTech Connect

    Gruissem, W.; Tonkyn, J.C.

    1993-12-31

    Plastid DNAs of higher plants contain approximately 150 genes that encode RNAs and proteins for genetic and photosynthetic functions of the organelle. Results published in the last few years illustrate that the spatial and temporal expression of these plastid genes is regulated, in part, at the transcriptional level, but that developmentally controlled changes in mRNA stability, translational activity, and protein phosphorylation also have an important role in the control of plastid functions. This comprehensive review summarizes and discusses the mechanisms by which regulation of gene expression is exerted at the transcriptional and post-transcriptional levels. It provides an overview of our current knowledge, but also emphasizes areas that are controversial and in which information on regulatory mechanisms is still incomplete. 455 refs., 3 figs., 3 tabs.

  13. Repression of gene expression by oxidative stress.

    PubMed Central

    Morel, Y; Barouki, R

    1999-01-01

    Gene expression is modulated by both physiological signals (hormones, cytokines, etc.) and environmental stimuli (physical parameters, xenobiotics, etc.). Oxidative stress appears to be a key pleiotropic modulator which may be involved in either pathway. Indeed, reactive oxygen species (ROS) have been described as second messengers for several growth factors and cytokines, but have also been shown to rise following cellular insults such as xenobiotic metabolism or enzymic deficiency. Extensive studies on the induction of stress-response genes by oxidative stress have been reported. In contrast, owing to the historical focus on gene induction, less attention has been paid to gene repression by ROS. However, a growing number of studies have shown that moderate (i.e. non-cytotoxic) oxidative stress specifically down-regulates the expression of various genes. In this review, we describe the alteration of several physiological functions resulting from oxidative-stress-mediated inhibition of gene transcription. We will then focus on the repressive oxidative modulation of various transcription factors elicited by ROS. PMID:10477257

  14. Aberrant placenta gene expression pattern in bovine pregnancies established after transfer of cloned or in vitro produced embryos.

    PubMed

    Salilew-Wondim, Dessie; Tesfaye, Dawit; Hossain, Munir; Held, Eva; Rings, Franca; Tholen, Ernst; Looft, Christian; Cinar, Ulas; Schellander, Karl; Hoelker, Michael

    2013-01-01

    In the present study, we used the global transcriptome profile approach to identify dysregulated genes, molecular pathways, and molecular functional alterations in bovine placentas derived from somatic cell nuclear transfer (SCNT) and in vitro embryo production (IVP) pregnancies compared with their artificial insemination (AI) counterparts at day 50 of gestation. For this, day 7 blastocysts derived from AI, IVP, or SCNT were transferred to oestrus-synchronized cows. The pregnant animals were slaughtered at day 50 of gestation, and the placentas were then recovered and used for transcriptome analysis using Affymetrix GeneChip bovine genome array. Results showed the SCNT placenta to be different from its AI counterpart in the expression of 1,196 transcripts. These genes were found to be associated with alterations in key biological processes and molecular pathways in SCNT placenta, and the dysregulation of 9% (n = 110) of these genes was due to transcriptional reprogramming error. IVP placenta also displayed alterations in the expression of 72 genes, of which 58 were common to SCNT placenta. Gene enrichment analysis revealed that the expression of genes involved in organ development, blood vessel development, extracellular matrix organization, and the immune system was affected in both SCNT and IVP placentas. However, 96% of the affected genes in SCNT were not significantly altered in IVP groups. Thus, the higher transcriptome dysregulation in SCNT placenta followed by IVP would reflect the degree of placental abnormality in SCNT and IVP pregnancies at day 50 of the gestation, which may have a profound effect on subsequent fetal development and health of the offspring.

  15. From gene expressions to genetic networks

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek

    2009-03-01

    A method based on the principle of entropy maximization is used to identify the gene interaction network with the highest probability of giving rise to experimentally observed transcript profiles [1]. In its simplest form, the method yields the pairwise gene interaction network, but it can also be extended to deduce higher order correlations. Analysis of microarray data from genes in Saccharomyces cerevisiae chemostat cultures exhibiting energy metabollic oscillations identifies a gene interaction network that reflects the intracellular communication pathways. These pathways adjust cellular metabolic activity and cell division to the limiting nutrient conditions that trigger metabolic oscillations. The success of the present approach in extracting meaningful genetic connections suggests that the maximum entropy principle is a useful concept for understanding living systems, as it is for other complex, nonequilibrium systems. The time-dependent behavior of the genetic network is found to involve only a few fundamental modes [2,3]. [4pt] REFERENCES:[0pt] [1] T. R. Lezon, J. R. Banavar, M. Cieplak, A. Maritan, and N. Fedoroff, Using the principle of entropy maximization to infer genetic interaction networks from gene expression patterns, Proc. Natl. Acad. Sci. (USA) 103, 19033-19038 (2006) [0pt] [2] N. S. Holter, M. Mitra, A. Maritan, M. Cieplak, J. R. Banavar, and N. V. Fedoroff, Fundamental patterns underlying gene expression profiles: simplicity from complexity, Proc. Natl. Acad. Sci. USA 97, 8409-8414 (2000) [0pt] [3] N. S. Holter, A. Maritan, M. Cieplak, N. V. Fedoroff, and J. R. Banavar, Dynamic modeling of gene expression data, Proc. Natl. Acad. Sci. USA 98, 1693-1698 (2001)

  16. Quality control in microarray assessment of gene expression in human airway epithelium

    PubMed Central

    Raman, Tina; O'Connor, Timothy P; Hackett, Neil R; Wang, Wei; Harvey, Ben-Gary; Attiyeh, Marc A; Dang, David T; Teater, Matthew; Crystal, Ronald G

    2009-01-01

    Background Microarray technology provides a powerful tool for defining gene expression profiles of airway epithelium that lend insight into the pathogenesis of human airway disorders. The focus of this study was to establish rigorous quality control parameters to ensure that microarray assessment of the airway epithelium is not confounded by experimental artifact. Samples (total n = 223) of trachea, large and small airway epithelium were collected by fiberoptic bronchoscopy of 144 individuals and hybridized to Affymetrix microarrays. The pre- and post-chip quality control (QC) criteria established, included: (1) RNA quality, assessed by RNA Integrity Number (RIN) ≥ 7.0; (2) cRNA transcript integrity, assessed by signal intensity ratio of GAPDH 3' to 5' probe sets ≤ 3.0; and (3) the multi-chip normalization scaling factor ≤ 10.0. Results Of the 223 samples, all three criteria were assessed in 191; of these 184 (96.3%) passed all three criteria. For the remaining 32 samples, the RIN was not available, and only the other two criteria were used; of these 29 (90.6%) passed these two criteria. Correlation coefficients for pairwise comparisons of expression levels for 100 maintenance genes in which at least one array failed the QC criteria (average Pearson r = 0.90 ± 0.04) were significantly lower (p < 0.0001) than correlation coefficients for pairwise comparisons between arrays that passed the QC criteria (average Pearson r = 0.97 ± 0.01). Inter-array variability was significantly decreased (p < 0.0001) among samples passing the QC criteria compared with samples failing the QC criteria. Conclusion Based on the aberrant maintenance gene data generated from samples failing the established QC criteria, we propose that the QC criteria outlined in this study can accurately distinguish high quality from low quality data, and can be used to delete poor quality microarray samples before proceeding to higher-order biological analyses and interpretation. PMID:19852842

  17. Molecular Sub-Classification of Renal Epithelial Tumors Using Meta-Analysis of Gene Expression Microarrays

    PubMed Central

    Sanford, Thomas; Chung, Paul H.; Reinish, Ariel; Valera, Vladimir; Srinivasan, Ramaprasad; Linehan, W. Marston; Bratslavsky, Gennady

    2011-01-01

    Purpose To evaluate the accuracy of the sub-classification of renal cortical neoplasms using molecular signatures. Experimental Design A search of publicly available databases was performed to identify microarray datasets with multiple histologic sub-types of renal cortical neoplasms. Meta-analytic techniques were utilized to identify differentially expressed genes for each histologic subtype. The lists of genes obtained from the meta-analysis were used to create predictive signatures through the use of a pair-based method. These signatures were organized into an algorithm to sub-classify renal neoplasms. The use of these signatures according to our algorithm was validated on several independent datasets. Results We identified three Gene Expression Omnibus datasets that fit our criteria to develop a training set. All of the datasets in our study utilized the Affymetrix platform. The final training dataset included 149 samples represented by the four most common histologic subtypes of renal cortical neoplasms: 69 clear cell, 41 papillary, 16 chromophobe, and 23 oncocytomas. When validation of our signatures was performed on external datasets, we were able to correctly classify 68 of the 72 samples (94%). The correct classification by subtype was 19/20 (95%) for clear cell, 14/14 (100%) for papillary, 17/19 (89%) for chromophobe, 18/19 (95%) for oncocytomas. Conclusions Through the use of meta-analytic techniques, we were able to create an algorithm that sub-classified renal neoplasms on a molecular level with 94% accuracy across multiple independent datasets. This algorithm may aid in selecting molecular therapies and may improve the accuracy of subtyping of renal cortical tumors. PMID:21818257

  18. Determining Physical Mechanisms of Gene Expression Regulation from Single Cell Gene Expression Data

    PubMed Central

    Moignard, Victoria; Göttgens, Berthold; Adryan, Boris

    2016-01-01

    Many genes are expressed in bursts, which can contribute to cell-to-cell heterogeneity. It is now possible to measure this heterogeneity with high throughput single cell gene expression assays (single cell qPCR and RNA-seq). These experimental approaches generate gene expression distributions which can be used to estimate the kinetic parameters of gene expression bursting, namely the rate that genes turn on, the rate that genes turn off, and the rate of transcription. We construct a complete pipeline for the analysis of single cell qPCR data that uses the mathematics behind bursty expression to develop more accurate and robust algorithms for analyzing the origin of heterogeneity in experimental samples, specifically an algorithm for clustering cells by their bursting behavior (Simulated Annealing for Bursty Expression Clustering, SABEC) and a statistical tool for comparing the kinetic parameters of bursty expression across populations of cells (Estimation of Parameter changes in Kinetics, EPiK). We applied these methods to hematopoiesis, including a new single cell dataset in which transcription factors (TFs) involved in the earliest branchpoint of blood differentiation were individually up- and down-regulated. We could identify two unique sub-populations within a seemingly homogenous group of hematopoietic stem cells. In addition, we could predict regulatory mechanisms controlling the expression levels of eighteen key hematopoietic transcription factors throughout differentiation. Detailed information about gene regulatory mechanisms can therefore be obtained simply from high throughput single cell gene expression data, which should be widely applicable given the rapid expansion of single cell genomics. PMID:27551778

  19. Coevolution of gene expression among interacting proteins

    SciTech Connect

    Fraser, Hunter B.; Hirsh, Aaron E.; Wall, Dennis P.; Eisen,Michael B.

    2004-03-01

    Physically interacting proteins or parts of proteins are expected to evolve in a coordinated manner that preserves proper interactions. Such coevolution at the amino acid-sequence level is well documented and has been used to predict interacting proteins, domains, and amino acids. Interacting proteins are also often precisely coexpressed with one another, presumably to maintain proper stoichiometry among interacting components. Here, we show that the expression levels of physically interacting proteins coevolve. We estimate average expression levels of genes from four closely related fungi of the genus Saccharomyces using the codon adaptation index and show that expression levels of interacting proteins exhibit coordinated changes in these different species. We find that this coevolution of expression is a more powerful predictor of physical interaction than is coevolution of amino acid sequence. These results demonstrate previously uncharacterized coevolution of gene expression, adding a different dimension to the study of the coevolution of interacting proteins and underscoring the importance of maintaining coexpression of interacting proteins over evolutionary time. Our results also suggest that expression coevolution can be used for computational prediction of protein protein interactions.

  20. Gene Expression Changes in C57BL/6J and DBA/2J Mice Following Prenatal Alcohol Exposure

    PubMed Central

    Downing, Chris; Flink, Stephen; Florez-McClure, Maria L.; Johnson, Thomas E.; Tabakoff, Boris; Kechris, Katerina J.

    2012-01-01

    Background Prenatal alcohol exposure can result in Fetal Alcohol Spectrum Disorder (FASD). Not all women who consume alcohol during pregnancy have children with FASD and studies have shown that genetic factors can play a role in ethanol teratogenesis. We examined gene expression in embryos and placentae from C57BL/6J (B6) and DBA/2J (D2) mice following prenatal alcohol exposure. B6 fetuses are susceptible to morphological malformations following prenatal alcohol exposure while D2 are relatively resistant. Methods Male and female B6 and D2 mice were mated for two hours in the morning, producing four embryonic genotypes: true-bred B6B6 and D2D2, and reciprocal B6D2 and D2B6. On gestational day 9dams were intubated with either 5.8 g/kg ethanol, an is caloric amount of maltose-dextrin, or nothing Four hours later dams were sacrificed and embryos and placentae were harvested. RNA was extracted, labeled and hybridized to Affymetrix Mouse Genome 430 v2 microarray chips. Data were normalized, subjected to analysis of variance and tested for enrichment of gene ontology (GO) molecular function and biological process using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Results Several gene classes were differentially expressed in B6 and D2 regardless of treatment, including genes involved in polysaccharide binding and mitosis. Prenatal alcohol exposure altered expression of a subset of genes, including genes involved in methylation, chromatin remodeling, protein synthesis and mRNA splicing. Very few genes were differentially expressed between maltose-exposed tissues and tissues that received nothing, so we combined these groups for comparisons with ethanol. While we observed many expression changes specific to B6 following prenatal alcohol exposure, none were specific for D2. Gene classes up-or down regulated in B6 following prenatal alcohol exposure included genes involved in mRNA splicing, transcription and translation. Conclusions Our study

  1. Subchronic Exposure to TCDD, PeCDF, PCB126, and PCB153: Effect on Hepatic Gene Expression

    PubMed Central

    Vezina, Chad M.; Walker, Nigel J.; Olson, James R.

    2004-01-01

    We employed DNA microarray to identify unique hepatic gene expression patterns associated with subchronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other halogenated aromatic hydrocarbons (HAHs). Female Harlan Sprague-Dawley rats were exposed for 13 weeks to toxicologically equivalent doses of four different HAHs based on the toxic equivalency factor of each chemical: TCDD (100 ng/kg/day), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF; 200 ng/kg/day), 3,3′,4,4′,5-pentachlorobiphenyl (PCB126; 1,000 ng/kg/day), or 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB153; 1,000 μg/kg/day). Global gene expression profiles for each exposure, which account for 8,799 gene probe sets contained on Affymetrix RGU34A GeneChips, were compared by principal components analysis. The aryl hydrocarbon receptor (AhR) ligands TCDD, PeCDF, and PCB126 produced very similar global gene expression profiles that were unique from the nonAhR ligand PCB153, underscoring the extensive impact of AhR activation and/or the resulting hepatic injury on global gene expression in female rat liver. Many genes were co-expressed during the 13-week TCDD, PeCDF, or PCB126 exposures, including classical AhR-regulated genes and some genes not previously characterized as being AhR regulated, such as carcinoembryonic-cell adhesion molecule 4 (C-CAM4) and adenylate cyclase-associated protein 2 (CAP2). Real-time reverse-transcriptase polymerase chain reaction confirmed the increased expression of these genes in TCDD-, PeCDF-, and PCB126-exposed rats as well as the up- or down-regulation of several other novel dioxin-responsive genes. In summary, DNA microarray successfully identified dioxin-responsive genes expressed after exposure to AhR ligands (TCDD, PeCDF, PCB126) but not after exposure to the non-AhR ligand PCB153. Together, these findings may help to elucidate some of the fundamental features of dioxin toxicity and may further clarify the biologic role of the AhR signaling pathway. PMID:15598615

  2. Gene expression regulation in roots under drought.

    PubMed

    Janiak, Agnieszka; Kwaśniewski, Mirosław; Szarejko, Iwona

    2016-02-01

    Stress signalling and regulatory networks controlling expression of target genes are the basis of plant response to drought. Roots are the first organs exposed to water deficiency in the soil and are the place of drought sensing. Signalling cascades transfer chemical signals toward the shoot and initiate molecular responses that lead to the biochemical and morphological changes that allow plants to be protected against water loss and to tolerate stress conditions. Here, we present an overview of signalling network and gene expression regulation pathways that are actively induced in roots under drought stress. In particular, the role of several transcription factor (TF) families, including DREB, AP2/ERF, NAC, bZIP, MYC, CAMTA, Alfin-like and Q-type ZFP, in the regulation of root response to drought are highlighted. The information provided includes available data on mutual interactions between these TFs together with their regulation by plant hormones and other signalling molecules. The most significant downstream target genes and molecular processes that are controlled by the regulatory factors are given. These data are also coupled with information about the influence of the described regulatory networks on root traits and root development which may translate to enhanced drought tolerance. This is the first literature survey demonstrating the gene expression regulatory machinery that is induced by drought stress, presented from the perspective of roots.

  3. Expression of bacterial genes in plant cells.

    PubMed Central

    Fraley, R T; Rogers, S G; Horsch, R B; Sanders, P R; Flick, J S; Adams, S P; Bittner, M L; Brand, L A; Fink, C L; Fry, J S; Galluppi, G R; Goldberg, S B; Hoffmann, N L; Woo, S C

    1983-01-01

    Chimeric bacterial genes conferring resistance to aminoglycoside antibiotics have been inserted into the Agrobacterium tumefaciens tumor-inducing (Ti) plasmid and introduced into plant cells by in vitro transformation techniques. The chimeric genes contain the nopaline synthase 5' and 3' regulatory regions joined to the genes for neomycin phosphotransferase type I or type II. The chimeric genes were cloned into an intermediate vector, pMON120, and inserted into pTiB6S3 by recombination and then introduced into petunia and tobacco cells by cocultivating A. tumefaciens cells with protoplast-derived cells. Southern hybridization was used to confirm the presence of the chimeric genes in the transformed plant tissues. Expression of the chimeric genes was determined by the ability of the transformed cells to proliferate on medium containing normally inhibitory levels of kanamycin (50 micrograms/ml) or other aminoglycoside antibiotics. Plant cells transformed by wild-type pTiB6S3 or derivatives carrying the bacterial neomycin phosphotransferase genes with their own promoters failed to grow under these conditions. The significance of these results for plant genetic engineering is discussed. Images PMID:6308651

  4. Gene expression pattern in canine mammary osteosarcoma.

    PubMed

    Pawłowski, K M; Majewska, A; Szyszko, K; Dolka, I; Motyl, T; Król, M

    2011-01-01

    Canine mammary sarcomas are usually very aggressive and easily metastasize. Unfortunately the biology of this type of tumor is not well known because they are a very rare type of tumors. The aim of this study was to find differences in gene expression patterns in canine mammary osteosarcomas (malignant) versus osteomas (benign) using DNA microarrays. Our microarray experiment showed that 11 genes were up-regulated in osteosarcoma in comparison to osteoma whereas 36 genes were down-regulated. Among the up-regulated genes were: PDK1, EXT1, and EIF4H which are involved in AKT/PI3K and GLI/Hedgehog pathways. These genes play an important role in cell biology (cancer cell proliferation) and may be essential in osteosarcoma formation and development. Analyzing the down-regulated genes, the most interesting seemed to be HSPB8 and SEPP1. HSPB8 is a small heat shock protein that plays an important role in cell cycle regulation, apoptosis, and breast carcinogenesis. Also SEPP1 may play a role in carcinogenesis, as its down-regulation may induce oxidative stress possibly resulting in carcinogenesis. The preliminary results of the present study indicate that the up-regulation of three genes EXT1, EIF4H, and PDK1 may play an essential role in osteosarcoma formation, development and proliferation. In our opinion the cross-talk between GLI/Hedgehog and PI3K/AKT pathways may be a key factor to increase tumor proliferation and malignancy. PMID:21528706

  5. Life stage differences in mammary gland gene expression profile in non-human primates

    PubMed Central

    Sielker, Sonja; Wood, Charles E.; Register, Thomas C.; Lees, Cynthia J.; Dewi, Fitriya N.; Williams, J. Koudy; Wagner, Janice D.; Stefenelli, Ulrich; Cline, J. Mark

    2013-01-01

    Breast cancer (BC) is the most common malignancy of women in the developed world. To better understand its pathogenesis, knowledge of normal breast development is crucial, as BC is the result of disregulation of physiologic processes. The aim of this study was to investigate the impact of reproductive life stages on the transcriptional profile of the mammary gland in a primate model. Comparative transcriptomic analyses were carried out using breast tissues from 28 female cynomolgus macaques (Macaca fascicularis) at the following life stages: prepubertal (n = 5), adolescent (n = 4), adult luteal (n = 5), pregnant (n = 6), lactating (n = 3), and postmenopausal (n = 5). Mammary gland RNA was hybridized to Affymetrix GeneChip® Rhesus Macaque Genome Arrays. Differential gene expression was analyzed using ANOVA and cluster analysis. Hierarchical cluster analysis revealed distinct separation of life stage groups. More than 2,225 differentially expressed mRNAs were identified. Gene families or pathways that changed across life stages included those related to estrogen and androgen (ESR1, PGR, TFF1, GREB1, AR, 17HSDB2, 17HSDB7, STS, HSD11B1, AKR1C4), prolactin (PRLR, ELF5, STAT5, CSN1S1), insulin-like growth factor signaling (IGF1, IGFBP1, IGFBP5), extracellular matrix (POSTN, TGFB1, COL5A2, COL12A1, FOXC1, LAMC1, PDG-FRA, TGFB2), and differentiation (CD24, CD29, CD44, CD61, ALDH1, BRCA1, FOXA1, POSTN, DICER1, LIG4, KLF4, NOTCH2, RIF1, BMPR1A, TGFB2). Pregnancy and lactation displayed distinct patterns of gene expression. ESR1 and IGF1 were significantly higher in the adolescent compared to the adult animals, whereas differentiation pathways were overrepresented in adult animals and pregnancy-associated life stages. Few individual genes were distinctly different in postmenopausal animals. Our data demonstrate characteristic patterns of gene expression during breast development. Several of the pathways activated during pubertal development have been implicated in cancer

  6. Effects of DMSA-coated Fe3O4 magnetic nanoparticles on global gene expression of mouse macrophage RAW264.7 cells.

    PubMed

    Liu, Yingxun; Chen, Zhongping; Gu, Ning; Wang, Jinke

    2011-08-28

    Fe(3)O(4) magnetic nanoparticles (MNPs) coated with 2,3-dimercaptosuccinnic acid (DMSA) are considered to be a promising nanomaterial with biocompatibility. In the present study, the effects of DMSA-coated Fe(3)O(4) MNPs on the expression of all identified mouse genes, which regulate various cellular biological processes, were determined to establish whether this nanoparticle is cytotoxic to mammalian cells. Mouse macrophage RAW264.7 cells were treated with 100μg/ml of DMSA-coated Fe(3)O(4) MNPs for 4, 24 and 48h, and the global gene expression was detected via Affymetrix Mouse Genome 430 2.0 GeneChips(®) microarrays. It was found that gene expression of 711, 545 and 434 transcripts was significantly altered by 4-, 24- and 48-h treatments, respectively. Of these genes, 27 were consistently upregulated and 6 were consistently downregulated at the three treatment durations. Bioinformatic analysis of all differentially expressed genes revealed that this nanoparticle can strongly activate inflammatory and immune responses and can inhibit the biosynthesis and metabolism of RAW264.7 cells at a dose of 100μg/ml. These results demonstrated that DMSA-coated Fe(3)O(4) MNPs display cytotoxicity in this type of macrophage at high doses.

  7. Altered gene expression of the innate immune, neuroendocrine, and nuclear factor-kappa B (NF-κB) systems is associated with posttraumatic stress disorder in military personnel.

    PubMed

    Guardado, Pedro; Olivera, Anlys; Rusch, Heather L; Roy, Michael; Martin, Christiana; Lejbman, Natasha; Lee, Hwyunhwa; Gill, Jessica M

    2016-03-01

    Whole transcriptome analysis provides an unbiased examination of biological activity, and likely, unique insight into the mechanisms underlying posttraumatic stress disorder (PTSD) and comorbid depression and traumatic brain injury. This study compared gene-expression profiles in military personnel with PTSD (n=28) and matched controls without PTSD (n=27) using HG-U133 Plus 2.0 microarrays (Affymetrix), which contain 54,675 probe sets representing more than 38,500 genes. Analysis of expression profiles revealed 203 differentially expressed genes in PTSD, of which 72% were upregulated. Using Partek Genomics Suite 6.6, differentially expressed transcription clusters were filtered based on a selection criterion of ≥1.5 relative fold change at a false discovery rate of ≤5%. Ingenuity Pathway Analysis (Qiagen) of the differentially expressed genes indicated a dysregulation of genes associated with the innate immune, neuroendocrine, and NF-κB systems. These findings provide novel insights that may lead to new pharmaceutical agents for PTSD treatments and help mitigate mental and physical comorbidity risk.

  8. Pathophysiological factors affecting CAR gene expression.

    PubMed

    Pascussi, Jean Marc; Dvorák, Zdenek; Gerbal-Chaloin, Sabine; Assenat, Eric; Maurel, Patrick; Vilarem, Marie José

    2003-11-01

    The body defends itself against potentially harmful compounds, such as drugs and toxic endogenous compounds and their metabolites, by inducing the expression of enzymes and transporters involved in their metabolism and elimination. The orphan nuclear receptor CAR (NR1I3 controls phase I (CYP2B, CYP2C, CYP3A), phase II (UGT1A1), and transporter (SLC21A6, MRP2) genes involved in drug metabolism and bilirubin clearance. Constitutive androstane receptor (CAR) is activated by xenobiotics, such as phenobarbital, but also by toxic endogenous compounds such as bilirubin metabolite(s). To better understand the inter- and intravariability in drug detoxification, we studied the molecular mechanisms involved in CAR gene expression in human hepatocytes. We clearly identified CAR as a glucocorticoid receptor (GR) target gene, and we proposed the hypothesis of a signal transduction where the activation of GR plays a critical function in CAR-mediated cellular response. According to our model, chemicals or pathophysiological factors that affect GR function should decrease CAR function. To test this hypothesis, we recently investigated the effect of microtubule disrupting agents (MIAs) or proinflammatory cytokines. These compounds are well-known inhibitors of GR transactivation property. MIAs activate c-Jun N-terminal kinase (JNK), which phosphorylates and inactivates GR, whereas proinflammatory cytokines, such as IL-6 or IL1beta, induce AP-1 or NF-kB activation, respectively, leading to GR inhibition. As expected, we observed that these molecules inhibit both CAR gene expression and phenobarbital-mediated CYP gene expression in human hepatocytes. PMID:14705859

  9. Gene expression profiles in skeletal muscle after gene electrotransfer

    PubMed Central

    Hojman, Pernille; Zibert, John R; Gissel, Hanne; Eriksen, Jens; Gehl, Julie

    2007-01-01

    Background Gene transfer by electroporation (DNA electrotransfer) to muscle results in high level long term transgenic expression, showing great promise for treatment of e.g. protein deficiency syndromes. However little is known about the effects of DNA electrotransfer on muscle fibres. We have therefore investigated transcriptional changes through gene expression profile analyses, morphological changes by histological analysis, and physiological changes by force generation measurements. DNA electrotransfer was obtained using a combination of a short high voltage pulse (HV, 1000 V/cm, 100 μs) followed by a long low voltage pulse (LV, 100 V/cm, 400 ms); a pulse combination optimised for efficient and safe gene transfer. Muscles were transfected with green fluorescent protein (GFP) and excised at 4 hours, 48 hours or 3 weeks after treatment. Results Differentially expressed genes were investigated by microarray analysis, and descriptive statistics were performed to evaluate the effects of 1) electroporation, 2) DNA injection, and 3) time after treatment. The biological significance of the results was assessed by gene annotation and supervised cluster analysis. Generally, electroporation caused down-regulation of structural proteins e.g. sarcospan and catalytic enzymes. Injection of DNA induced down-regulation of intracellular transport proteins e.g. sentrin. The effects on muscle fibres were transient as the expression profiles 3 weeks after treatment were closely related with the control muscles. Most interestingly, no changes in the expression of proteins involved in inflammatory responses or muscle regeneration was detected, indicating limited muscle damage and regeneration. Histological analysis revealed structural changes with loss of cell integrity and striation pattern in some fibres after DNA+HV+LV treatment, while HV+LV pulses alone showed preservation of cell integrity. No difference in the force generation capacity was observed in the muscles 2 weeks

  10. Comparative expression profiling in primary and immortalized endothelial cells: changes in gene expression in response to hydroxy methylglutaryl-coenzyme A reductase inhibition.

    PubMed

    Boerma, Marjan; Burton, Gregory R; Wang, Junru; Fink, Louis M; McGehee, Robert E; Hauer-Jensen, Martin

    2006-04-01

    Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as

  11. A genome-wide expression profile and system-level integration of nuclear factor kappa B regulated genes reveals fundamental metabolic adaptations during cell growth and survival.

    PubMed

    Andela, Valentine B; Schwarz, Edward M; O'Keefe, Regis J; Puzas, Edward J; Rosenblatt, Joseph D; Rosier, Randy N

    2005-12-19

    A murine lung alveolar carcinoma cell line (WT-Line 1) and its equally tumorigenic but non-malignant derivative transduced with a dominant negative inhibitor of NF-kappaB (mI-kappaB-Line 1), were profiled on the Affymetrix 19000 gene array platform. Two differentially expressed gene clusters were identified and integrated into a functional model. The downregulation of anti-oxidant defenses, in mI-kappaB-Line 1 cells, correlates with high levels of reactive oxygen species (ROS) and ROS damage to cellular macromolecules while the upregulation of metabolic nuclear receptors correlates with an adaptive/survival response, which involves a shift in energy metabolism toward beta-oxidative respiration. Accordingly, mI-kappaB-Line 1 cells are markedly sensitized to pharmacologic inhibition of beta-oxidative respiration. These findings are indicative of compensatory changes that could undermine anti-cancer therapies targeting NF-kappaB.

  12. Changes in gene expression profiles in response to selenium supplementation among individuals with arsenic-induced pre-malignant skin lesions.

    PubMed

    Kibriya, Muhammad G; Jasmine, Farzana; Argos, Maria; Verret, Wendy J; Rakibuz-Zaman, Muhammad; Ahmed, Alauddin; Parvez, Faruque; Ahsan, Habibul

    2007-03-01

    The molecular basis and downstream targets of oral selenium supplementation in individuals with elevated risk of cancer due to chronic exposure from environmental carcinogens has been largely unexplored. In this study, we investigated genome-wide differential gene expression in peripheral blood mononuclear cells (PBMC) from individuals with pre-malignant arsenic (As)-induced skin lesions before and after 6 months daily oral supplementation of 200 microg L-selenomethionine. The Affymetrix GeneChip Human 133A 2.0 array, containing probes for 22,277 gene transcripts, was used to assess gene expression. Three different normalization methods, RMA (robust multi-chip analysis), GC-RMA and PLIER (Probe logarithmic intensity error), were applied to explore differentially expressed genes. We identified a list of 28 biologically meaningful, significantly differentially expressed genes. Genes up-regulated by selenium supplementation included TNF, IL1B, IL8, SOD2, CXCL2 and several other immunological and oxidative stress-related genes. When mapped to a biological association network, many of the differentially expressed genes were found to regulate functional classes such as fibroblast growth factor, collagenase, matrix metalloproteinase and stromelysin-1, and thus, considered to affect cellular processes like apoptosis, proliferation and others. Many of the significantly up-regulated genes following selenium-supplementation were previously found by us to be down-regulated in a different set of individuals with As-induced skin lesions compared to those without. In conclusion, findings from this study may elucidate the biological effect of selenium supplementation in humans. Additionally, this study suggests that long-term selenium supplementation may revert some of the gene expression changes presumably induced by chronic As exposure in individuals with pre-malignant skin lesions.

  13. Decomposition of Gene Expression State Space Trajectories

    PubMed Central

    Mar, Jessica C.; Quackenbush, John

    2009-01-01

    Representing and analyzing complex networks remains a roadblock to creating dynamic network models of biological processes and pathways. The study of cell fate transitions can reveal much about the transcriptional regulatory programs that underlie these phenotypic changes and give rise to the coordinated patterns in expression changes that we observe. The application of gene expression state space trajectories to capture cell fate transitions at the genome-wide level is one approach currently used in the literature. In this paper, we analyze the gene expression dataset of Huang et al. (2005) which follows the differentiation of promyelocytes into neutrophil-like cells in the presence of inducers dimethyl sulfoxide and all-trans retinoic acid. Huang et al. (2005) build on the work of Kauffman (2004) who raised the attractor hypothesis, stating that cells exist in an expression landscape and their expression trajectories converge towards attractive sites in this landscape. We propose an alternative interpretation that explains this convergent behavior by recognizing that there are two types of processes participating in these cell fate transitions—core processes that include the specific differentiation pathways of promyelocytes to neutrophils, and transient processes that capture those pathways and responses specific to the inducer. Using functional enrichment analyses, specific biological examples and an analysis of the trajectories and their core and transient components we provide a validation of our hypothesis using the Huang et al. (2005) dataset. PMID:20041215

  14. Time-dependent changes in gene expression induced by secreted amyloid precursor protein-alpha in the rat hippocampus

    PubMed Central

    2013-01-01

    Background Differential processing of the amyloid precursor protein liberates either amyloid-ß, a causative agent of Alzheimer’s disease, or secreted amyloid precursor protein-alpha (sAPPα), which promotes neuroprotection, neurotrophism, neurogenesis and synaptic plasticity. The underlying molecular mechanisms recruited by sAPPα that underpin these considerable cellular effects are not well elucidated. As these effects are enduring, we hypothesised that regulation of gene expression may be of importance and examined temporally specific gene networks and pathways induced by sAPPα in rat hippocampal organotypic slice cultures. Slices were exposed to 1 nM sAPPα or phosphate buffered saline for 15 min, 2 h or 24 h and sAPPα-associated gene expression profiles were produced for each time-point using Affymetrix Rat Gene 1.0 ST arrays (moderated t-test using Limma: p < 0.05, and fold change ± 1.15). Results Treatment of organotypic hippocampal slice cultures with 1 nM sAPPα induced temporally distinct gene expression profiles, including mRNA and microRNA associated with Alzheimer’s disease. Having demonstrated that treatment with human recombinant sAPPα was protective against N-methyl d-aspartate-induced toxicity, we next explored the sAPPα-induced gene expression profiles. Ingenuity Pathway Analysis predicted that short-term exposure to sAPPα elicited a multi-level transcriptional response, including upregulation of immediate early gene transcription factors (AP-1, Egr1), modulation of the chromatin environment, and apparent activation of the constitutive transcription factors CREB and NF-κB. Importantly, dynamic regulation of NF-κB appears to be integral to the transcriptional response across all time-points. In contrast, medium and long exposure to sAPPα resulted in an overall downregulation of gene expression. While these results suggest commonality between sAPPα and our previously reported analysis of plasticity-related gene expression, we

  15. Insights into SAGA function during gene expression

    PubMed Central

    Rodríguez-Navarro, Susana

    2009-01-01

    Histone modifications are a crucial source of epigenetic control. SAGA (Spt–Ada–Gcn5 acetyltransferase) is a chromatin-modifying complex that contains two distinct enzymatic activities, Gcn5 and Ubp8, through which it acetylates and deubiquitinates histone residues, respectively, thereby enforcing a pattern of modifications that is decisive in regulating gene expression. Here, I discuss the latest contributions to understanding the roles of the SAGA complex, highlighting the characterization of the SAGA-deubiquitination module, and emphasizing the functions newly ascribed to SAGA during transcription elongation and messenger-RNA export. These findings suggest that a crosstalk exists between chromatin remodelling, transcription and messenger-RNA export, which could constitute a checkpoint for accurate gene expression. I focus particularly on the new components of human SAGA, which was recently discovered and confirms the conservation of the SAGA complex throughout evolution. PMID:19609321

  16. Structure, expression and functions of MTA genes.

    PubMed

    Kumar, Rakesh; Wang, Rui-An

    2016-05-15

    Metastatic associated proteins (MTA) are integrators of upstream regulatory signals with the ability to act as master coregulators for modifying gene transcriptional activity. The MTA family includes three genes and multiple alternatively spliced variants. The MTA proteins neither have their own enzymatic activity nor have been shown to directly interact with DNA. However, MTA proteins interact with a variety of chromatin remodeling factors and complexes with enzymatic activities for modulating the plasticity of nucleosomes, leading to the repression or derepression of target genes or other extra-nuclear and nucleosome remodeling and histone deacetylase (NuRD)-complex independent activities. The functions of MTA family members are driven by the steady state levels and subcellular localization of MTA proteins, the dynamic nature of modifying signals and enzymes, the structural features and post-translational modification of protein domains, interactions with binding proteins, and the nature of the engaged and resulting features of nucleosomes in the proximity of target genes. In general, MTA1 and MTA2 are the most upregulated genes in human cancer and correlate well with aggressive phenotypes, therapeutic resistance, poor prognosis and ultimately, unfavorable survival of cancer patients. Here we will discuss the structure, expression and functions of the MTA family of genes in the context of cancer cells. PMID:26869315

  17. Identifying driver genes in cancer by triangulating gene expression, gene location, and survival data.

    PubMed

    Rouam, Sigrid; Miller, Lance D; Karuturi, R Krishna Murthy

    2014-01-01

    Driver genes are directly responsible for oncogenesis and identifying them is essential in order to fully understand the mechanisms of cancer. However, it is difficult to delineate them from the larger pool of genes that are deregulated in cancer (ie, passenger genes). In order to address this problem, we developed an approach called TRIAngulating Gene Expression (TRIAGE through clinico-genomic intersects). Here, we present a refinement of this approach incorporating a new scoring methodology to identify putative driver genes that are deregulated in cancer. TRIAGE triangulates - or integrates - three levels of information: gene expression, gene location, and patient survival. First, TRIAGE identifies regions of deregulated expression (ie, expression footprints) by deriving a newly established measure called the Local Singular Value Decomposition (LSVD) score for each locus. Driver genes are then distinguished from passenger genes using dual survival analyses. Incorporating measurements of gene expression and weighting them according to the LSVD weight of each tumor, these analyses are performed using the genes located in significant expression footprints. Here, we first use simulated data to characterize the newly established LSVD score. We then present the results of our application of this refined version of TRIAGE to gene expression data from five cancer types. This refined version of TRIAGE not only allowed us to identify known prominent driver genes, such as MMP1, IL8, and COL1A2, but it also led us to identify several novel ones. These results illustrate that TRIAGE complements existing tools, allows for the identification of genes that drive cancer and could perhaps elucidate potential future targets of novel anticancer therapeutics.

  18. In silico analysis of gene expression profiles in the olfactory mucosae of aging senescence-accelerated mice.

    PubMed

    Getchell, Thomas V; Peng, Xuejun; Green, C Paul; Stromberg, Arnold J; Chen, Kuey-Chu; Mattson, Mark P; Getchell, Marilyn L

    2004-08-01

    We utilized high-density Affymetrix oligonucleotide arrays to investigate gene expression in the olfactory mucosae of near age-matched aging senescence-accelerated mice (SAM). The senescence-prone (SAMP) strain has a significantly shorter lifespan than does the senescence-resistant (SAMR) strain. To analyze our data, we applied biostatistical methods that included a correlation analysis to evaluate sources of methodologic and biological variability; a two-sided t-test to identify a subpopulation of Present genes with a biologically relevant P-value <0.05; and a false discovery rate (FDR) analysis adjusted to a stringent 5% level that yielded 127 genes with a P-value of <0.001 that were differentially regulated in near age-matched SAMPs (SAMP-Os; 13.75 months) compared to SAMRs (SAMR-Os, 12.5 months). Volcano plots related the variability in the mean hybridization signals as determined by the two-sided t-test to fold changes in gene expression. The genes were categorized into the six functional groups used previously in gene profiling experiments to identify candidate genes that may be relevant for senescence at the genomic and cellular levels in the aging mouse brain (Lee et al. [2000] Nat Genet 25:294-297) and in the olfactory mucosa (Getchell et al. [2003] Ageing Res Rev 2:211-243), which serves several functions that include chemosensory detection, immune barrier function, xenobiotic metabolism, and neurogenesis. Because SAMR-Os and SAMP-Os have substantially different median lifespans, we related the rate constant alpha in the Gompertz equation on aging to intrinsic as opposed to environmental mechanisms of senescence based on our analysis of genes modulated during aging in the olfactory mucosa. PMID:15248299

  19. Gene expression: RNA interference in adult mice

    NASA Astrophysics Data System (ADS)

    McCaffrey, Anton P.; Meuse, Leonard; Pham, Thu-Thao T.; Conklin, Douglas S.; Hannon, Gregory J.; Kay, Mark A.

    2002-07-01

    RNA interference is an evolutionarily conserved surveillance mechanism that responds to double-stranded RNA by sequence-specific silencing of homologous genes. Here we show that transgene expression can be suppressed in adult mice by synthetic small interfering RNAs and by small-hairpin RNAs transcribed in vivo from DNA templates. We also show the therapeutic potential of this technique by demonstrating effective targeting of a sequence from hepatitis C virus by RNA interference in vivo.

  20. Imaging gene expression in single living cells

    PubMed Central

    Shav-Tal, Yaron; Singer, Robert H.; Darzacq, Xavier

    2016-01-01

    Technical advances in the field of live-cell imaging have introduced the cell biologist to a new, dynamic, subcellular world. The static world of molecules in fixed cells has now been extended to the time dimension. This allows the visualization and quantification of gene expression and intracellular trafficking events of the studied molecules and the associated enzymatic processes in individual cells, in real time. PMID:15459666

  1. The systemic control of circadian gene expression.

    PubMed

    Gerber, A; Saini, C; Curie, T; Emmenegger, Y; Rando, G; Gosselin, P; Gotic, I; Gos, P; Franken, P; Schibler, U

    2015-09-01

    The mammalian circadian timing system consists of a central pacemaker in the brain's suprachiasmatic nucleus (SCN) and subsidiary oscillators in nearly all body cells. The SCN clock, which is adjusted to geophysical time by the photoperiod, synchronizes peripheral clocks through a wide variety of systemic cues. The latter include signals depending on feeding cycles, glucocorticoid hormones, rhythmic blood-borne signals eliciting daily changes in actin dynamics and serum response factor (SRF) activity, and sensors of body temperature rhythms, such as heat shock transcription factors and the cold-inducible RNA-binding protein CIRP. To study these systemic signalling pathways, we designed and engineered a novel, highly photosensitive apparatus, dubbed RT-Biolumicorder. This device enables us to record circadian luciferase reporter gene expression in the liver and other organs of freely moving mice over months in real time. Owing to the multitude of systemic signalling pathway involved in the phase resetting of peripheral clocks the disruption of any particular one has only minor effects on the steady state phase of circadian gene expression in organs such as the liver. Nonetheless, the implication of specific pathways in the synchronization of clock gene expression can readily be assessed by monitoring the phase-shifting kinetics using the RT-Biolumicorder.

  2. Carbon Nanomaterials Alter Global Gene Expression Profiles.

    PubMed

    Woodman, Sara; Short, John C W; McDermott, Hyoeun; Linan, Alexander; Bartlett, Katelyn; Gadila, Shiva Kumar Goud; Schmelzle, Katie; Wanekaya, Adam; Kim, Kyoungtae

    2016-05-01

    Carbon nanomaterials (CNMs), which include carbon nanotubes (CNTs) and their derivatives, have diverse technological and biomedical applications. The potential toxicity of CNMs to cells and tissues has become an important emerging question in nanotechnology. To assess the toxicity of CNTs and fullerenol C60(OH)24, we in the present work used the budding yeast Saccharomyces cerevisiae, one of the simplest eukaryotic organisms that share fundamental aspects of eukaryotic cell biology. We found that treatment with CNMs, regardless of their physical shape, negatively affected the growth rates, end-point cell densities and doubling times of CNM-exposed yeast cells when compared to unexposed cells. To investigate potential mechanisms behind the CNMs-induced growth defects, we performed RNA-Seq dependent transcriptional analysis and constructed global gene expression profiles of fullerenol C60(OH)24- and CNT-treated cells. When compared to non-treated control cells, CNM-treated cells displayed differential expression of genes whose functions are implicated in membrane transporters and stress response, although differentially expressed genes were not consistent between CNT- and fullerenol C60(OH)24-treated groups, leading to our conclusion that CNMs could serve as environmental toxic factors to eukaryotic cells. PMID:27483901

  3. Expression of foreign genes in filamentous cyanobacteria

    SciTech Connect

    Kuritz, T.; Wolk, C.P. )

    1993-06-01

    Several advantages make cyanobacteria attractive hosts for biodegradative genes and possibly for other exogenous genes that have practical uses. The authors have obtained expression in Anabaena sp. strain PCC 7120 and Nostoc ellipsosporum of a dechlorination operon, fcbAB, from Arthrobacter globiformis, and have also developed a simple method for qualitative assessment of dechlorination by microorganisms, such as cyanobacteria, whose metabolism is dependent on the presence of chloride in the medium. Transcription of fcbAB under the control of a variety of promoters was monitored by placing luxAB (encoding luciferase) downstream from fcbAB, and by measuring light emission from luciferase. They believe that the system that they have described has value as a means to screen for factors influencing transcription of foreign genes in cyanobacteria.

  4. [Transcriptomes for serial analysis of gene expression].

    PubMed

    Marti, Jacques; Piquemal, David; Manchon, Laurent; Commes, Thérèse

    2002-01-01

    The availability of the sequences for whole genomes is changing our understanding of cell biology. Functional genomics refers to the comprehensive analysis, at the protein level (proteome) and at the mRNA level (transcriptome) of all events associated with the expression of whole sets of genes. New methods have been developed for transcriptome analysis. Serial Analysis of Gene Expression (SAGE) is based on the massive sequential analysis of short cDNA sequence tags. Each tag is derived from a defined position within a transcript. Its size (14 bp) is sufficient to identify the corresponding gene and the number of times each tag is observed provides an accurate measurement of its expression level. Since tag populations can be widely amplified without altering their relative proportions, SAGE may be performed with minute amounts of biological extract. Dealing with the mass of data generated by SAGE necessitates computer analysis. A software is required to automatically detect and count tags from sequence files. Criterias allowing to assess the quality of experimental data can be included at this stage. To identify the corresponding genes, a database is created registering all virtual tags susceptible to be observed, based on the present status of the genome knowledge. By using currently available database functions, it is easy to match experimental and virtual tags, thus generating a new database registering identified tags, together with their expression levels. As an open system, SAGE is able to reveal new, yet unknown, transcripts. Their identification will become increasingly easier with the progress of genome annotation. However, their direct characterization can be attempted, since tag information may be sufficient to design primers allowing to extend unknown sequences. A major advantage of SAGE is that, by measuring expression levels without reference to an arbitrary standard, data are definitively acquired and cumulative. All publicly available data can thus

  5. Gestation under chronic constant light leads to extensive gene expression changes in the fetal rat liver.

    PubMed

    Spichiger, Carlos; Torres-Farfan, Claudia; Galdames, Hugo A; Mendez, Natalia; Alonso-Vazquez, Pamela; Richter, Hans G

    2015-12-01

    Recent reports account for altered metabolism in adult offspring from pregnancy subjected to abnormal photoperiod, suggesting fetal programming of liver physiology. To generate a pipeline of subsequent mechanistic experiments addressing strong candidate genes, here we investigated the effects of constant gestational light on the fetal liver transcriptome. At 10 days of gestation, dams were randomized in two groups (n = 7 each): constant light (LL) and normal photoperiod (12 h light/12 h dark; LD). At 18 days of gestation, RNA was isolated from the fetal liver and subjected to DNA microarray (Affymetrix platform for 28,000 genes). Selected differential mRNAs were validated by quantitative PCR (qPCR), while integrated transcriptional changes were analyzed with Ingenuity Pathway Analysis and other bioinformatics tools. Comparison of LL relative to LD fetal liver led to the following findings. Significant differential expression was found for 3,431 transcripts (1,960 upregulated and 1,471 downregulated), with 393 of them displaying ≥ 1.5-fold change. We validated 27 selected transcripts by qPCR, which displayed fold-change values highly correlated with microarray (r(2) = 0.91). Different markers of nonalcoholic fatty liver disease were either upregulated (e.g., Ndn and Pnpla3) or downregulated (e.g., Gnmt, Bhmt1/2, Sult1a1, Mpo, and Mat1a). Diverse pathways were altered, including hematopoiesis, coagulation cascade, complement system, and carbohydrate and lipid metabolism. The microRNAs 7a-1, 431, 146a, and 153 were upregulated, while the abundant hepatic miRNA 122 was downregulated. Constant gestational light induced extensive modification of the fetal liver transcriptome. A number of differentially expressed transcripts belong to fundamental functional pathways, potentially contributing to long-term liver disease.

  6. Reduced expression of Autographa californica nucleopolyhedrovirus ORF34, an essential gene, enhances heterologous gene expression

    SciTech Connect

    Salem, Tamer Z.; Zhang, Fengrui; Thiem, Suzanne M.

    2013-01-20

    Autographa californica multiple nucleopolyhedrovirus ORF34 is part of a transcriptional unit that includes ORF32, encoding a viral fibroblast growth factor (FGF) and ORF33. We identified ORF34 as a candidate for deletion to improve protein expression in the baculovirus expression system based on enhanced reporter gene expression in an RNAi screen of virus genes. However, ORF34 was shown to be an essential gene. To explore ORF34 function, deletion (KO34) and rescue bacmids were constructed and characterized. Infection did not spread from primary KO34 transfected cells and supernatants from KO34 transfected cells could not infect fresh Sf21 cells whereas the supernatant from the rescue bacmids transfection could recover the infection. In addition, budded viruses were not observed in KO34 transfected cells by electron microscopy, nor were viral proteins detected from the transfection supernatants by western blots. These demonstrate that ORF34 is an essential gene with a possible role in infectious virus production.

  7. Screening of differentially expressed genes in pathological scar tissues using expression microarray.

    PubMed

    Huang, L P; Mao, Z; Zhang, L; Liu, X X; Huang, C; Jia, Z S

    2015-01-01

    Pathological scar tissues and normal skin tissues were differentiated by screening for differentially expressed genes in pathologic scar tissues via gene expression microarray. The differentially expressed gene data was analyzed by gene ontology and pathway analyses. There were 5001 up- or down-regulated genes in 2-fold differentially expressed genes, 956 up- or down-regulated genes in 5-fold differentially expressed genes, and 114 up- or down-regulated genes in 20-fold differentially expressed genes. Therefore, significant differences were observed in the gene expression in pathological scar tissues and normal foreskin tissues. The development of pathological scar tissues has been correlated to changes in multiple genes and pathways, which are believed to form a dynamic network connection.

  8. DISTINCT EFFECTS OF CALORIE RESTRICTION AND EXERCISE ON MAMMARY GLAND GENE EXPRESSION IN C57BL/6 MICE

    PubMed Central

    Padovani, Michela; Lavigne, Jackie A.; Chandramouli, Gadisetti V.R.; Perkins, Susan N.; Barrett, J. Carl; Hursting, Stephen D.; Bennett, L. Michelle; Berrigan, David

    2009-01-01

    Energy balance, including diet, weight, adiposity, and physical activity is associated with carcinogenesis. Epidemiological studies indicate that obesity and sedentary and/or active behavior are risk factors for breast cancer in postmenopausal women and survival in both pre-and postmenopausal breast cancer patients. Thus, understanding energy balance modulation’s influence on changes in gene expression patterns in the normal mammary gland is important for understanding mechanisms linking energy balance and breast cancer. In a six week long study, female C57BL/6 mice (9 weeks old) were randomized into four groups: 1) food consumed ad libitum (AL); 2) AL with access to running wheels (AL+EX); 3) 30% Calorie Restricted (CR); and 4) 30% CR with access to running wheels (CR+EX). CR mice received 70% of calories but 100% of all other nutrients compared to AL mice. Diet and exercise treatments individually and combined, had significant effects on body composition and physical activity. Affymetrix oligo-microarrays were used to explore changes in gene expression patterns in total RNA samples from excised whole mammary glands. Contrasting AL versus CR resulted in 425 statistically significant expression changes whereas AL versus AL +EX resulted in 45 changes, with only 3 changes included the same genes, indicating that CR and EX differentially influence expression patterns in non-cancerous mammary tissue. Differential expression was observed in genes related to breast cancer stem cells, the epithelial -mesenchymal transition, and the growth and survival of breast cancer cells. Thus, CR and EX appear to exert their effects on mammary carcinogenesis through distinct pathways. PMID:19952363

  9. Wnt5a participates in hepatic stellate cell activation observed by gene expression profile and functional assays

    PubMed Central

    Xiong, Wu-Jun; Hu, Li-Juan; Jian, Yi-Cheng; Wang, Li-Jing; Jiang, Ming; Li, Wei; He, Yi

    2012-01-01

    AIM: To identify differentially expressed genes in quiescent and activated hepatic stellate cells (HSCs) and explore their functions. METHODS: HSCs were isolated from the normal Sprague Dawley rats by in suit perfusion of collagenase and pronase and density Nycodenz gradient centrifugation. Total RNA and mRNA of quiescent HSCs, and culture-activated HSCs were extracted, quantified and reversely transcripted into cDNA. The global gene expression profile was analyzed by microarray with Affymetrix rat genechip. Differentially expressed genes were annotated with Gene Ontology (GO) and analyzed with Kyoto encyclopedia of genes and genomes (KEGG) pathway using the Database for Annotation, Visualization and Integrated Discovery. Microarray data were validated by quantitative real-time polymerase chain reaction (qRT-PCR). The function of Wnt5a on human HSCs line LX-2 was assessed with lentivirus-mediated Wnt5a RNAi. The expression of Wnt5a in fibrotic liver of a carbon tetrachloride (CCl4)-induced fibrosis rat model was also analyzed with Western blotting. RESULTS: Of the 28 700 genes represented on this chip, 2566 genes displayed at least a 2-fold increase or decrease in expression at a P < 0.01 level with a false discovery rate. Of these, 1396 genes were upregulated, while 1170 genes were downregulated in culture-activated HSCs. These differentially expressed transcripts were grouped into 545 GO based on biological process GO terms. The most enriched GO terms included response to wounding, wound healing, regulation of cell growth, vasculature development and actin cytoskeleton organization. KEGG pathway analysis revealed that Wnt5a signaling pathway participated in the activation of HSCs. Wnt5a was significantly increased in culture-activated HSCs as compared with quiescent HSCs. qRT-PCR validated the microarray data. Lentivirus-mediated suppression of Wnt5a expression in activated LX-2 resulted in significantly impaired proliferation, downregulated expressions of

  10. Analysis of Changes in Hepatic Gene Expression in a Murine Model of Tolerance to Acetaminophen Hepatotoxicity (Autoprotection)

    PubMed Central

    O’Connor, Meeghan A; Koza-Taylor, Petra; Campion, Sarah N; Aleksunes, Lauren M; Gu, Xinsheng; Enayetallah, Ahmed E.; Lawton, Michael P; Manautou, José E

    2013-01-01

    Pretreatment of mice with a low hepatotoxic dose of acetaminophen (APAP) results in resistance to a subsequent, higher dose of APAP. This mouse model, termed APAP autoprotection was used here to identify differentially expressed genes and cellular pathways that could contribute to this development of resistance to hepatotoxicity. Male C57BL/6J mice were pretreated with APAP (400 mg/kg) and then challenged 48 hr later with 600 mg APAP/kg. Livers were obtained 4 or 24 hr later and total hepatic RNA was isolated and hybridized to Affymetrix Mouse Genome MU430_2 GeneChip. Statistically significant genes were determined and gene expression changes were also interrogated using the Causal Reasoning Engine (CRE). Extensive literature review narrowed our focus to methionine adenosyl transferase-1 alpha (MAT1A), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), flavin-containing monooxygenase 3 (Fmo3) and galectin-3 (Lgals3). Down-regulation of MAT1A could lead to decreases in S-adenosylmethionine (SAMe), which is known to protect against APAP toxicity. Nrf2 activation is expected to play a role in protective adaptation. Up-regulation of Lgals3, one of the genes supporting the Nrf2 hypothesis, can lead to suppression of apoptosis and reduced mitochondrial dysfunction. Fmo3 induction suggests the involvement of an enzyme not known to metabolize APAP in the development of tolerance to APAP toxicity. Subsequent quantitative RT-PCR and immunochemical analysis confirmed the differential expression of some of these genes in the APAP autoprotection model. In conclusion, our genomics strategy identified cellular pathways that might further explain the molecular basis for APAP autoprotection. PMID:24126418

  11. Subchronic treatment with aldosterone induces depression-like behaviours and gene expression changes relevant to major depressive disorder.

    PubMed

    Hlavacova, Natasa; Wes, Paul D; Ondrejcakova, Maria; Flynn, Marianne E; Poundstone, Patricia K; Babic, Stanislav; Murck, Harald; Jezova, Daniela

    2012-03-01

    The potential role of aldosterone in the pathophysiology of depression is unclear. The aim of this study was to test the hypothesis that prolonged elevation of circulating aldosterone induces depression-like behaviour accompanied by disease-relevant changes in gene expression in the hippocampus. Subchronic (2-wk) treatment with aldosterone (2 μg/100 g body weight per day) or vehicle via subcutaneous osmotic minipumps was used to induce hyperaldosteronism in male rats. All rats (n = 20/treatment group) underwent a modified sucrose preference test. Half of the animals from each treatment group were exposed to the forced swim test (FST), which served both as a tool to assess depression-like behaviour and as a stress stimulus. Affymetrix microarray analysis was used to screen the entire rat genome for gene expression changes in the hippocampus. Aldosterone treatment induced an anhedonic state manifested by decreased sucrose preference. In the FST, depressogenic action of aldosterone was manifested by decreased latency to immobility and increased time spent immobile. Aldosterone treatment resulted in transcriptional changes of genes in the hippocampus involved in inflammation, glutamatergic activity, and synaptic and neuritic remodelling. Furthermore, aldosterone-regulated genes substantially overlapped with genes affected by stress in the FST. This study demonstrates the existence of a causal relationship between the hyperaldosteronism and depressive behaviour. In addition, aldosterone treatment induced changes in gene expression that may be relevant to the aetiology of major depressive disorder. Subchronic treatment with aldosterone represents a new animal model of depression, which may contribute to the development of novel targets for the treatment of depression.

  12. Analysis of changes in hepatic gene expression in a murine model of tolerance to acetaminophen hepatotoxicity (autoprotection).

    PubMed

    O'Connor, Meeghan A; Koza-Taylor, Petra; Campion, Sarah N; Aleksunes, Lauren M; Gu, Xinsheng; Enayetallah, Ahmed E; Lawton, Michael P; Manautou, José E

    2014-01-01

    Pretreatment of mice with a low hepatotoxic dose of acetaminophen (APAP) results in resistance to a subsequent, higher dose of APAP. This mouse model, termed APAP autoprotection was used here to identify differentially expressed genes and cellular pathways that could contribute to this development of resistance to hepatotoxicity. Male C57BL/6J mice were pretreated with APAP (400mg/kg) and then challenged 48h later with 600mg APAP/kg. Livers were obtained 4 or 24h later and total hepatic RNA was isolated and hybridized to Affymetrix Mouse Genome MU430_2 GeneChip. Statistically significant genes were determined and gene expression changes were also interrogated using the Causal Reasoning Engine (CRE). Extensive literature review narrowed our focus to methionine adenosyl transferase-1 alpha (MAT1A), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), flavin-containing monooxygenase 3 (Fmo3) and galectin-3 (Lgals3). Down-regulation of MAT1A could lead to decreases in S-adenosylmethionine (SAMe), which is known to protect against APAP toxicity. Nrf2 activation is expected to play a role in protective adaptation. Up-regulation of Lgals3, one of the genes supporting the Nrf2 hypothesis, can lead to suppression of apoptosis and reduced mitochondrial dysfunction. Fmo3 induction suggests the involvement of an enzyme not known to metabolize APAP in the development of tolerance to APAP toxicity. Subsequent quantitative RT-PCR and immunochemical analysis confirmed the differential expression of some of these genes in the APAP autoprotection model. In conclusion, our genomics strategy identified cellular pathways that might further explain the molecular basis for APAP autoprotection. PMID:24126418

  13. Sequential Alterations in Catabolic and Anabolic Gene Expression Parallel Pathological Changes during Progression of Monoiodoacetate-Induced Arthritis

    PubMed Central

    Liu, Jie; Rath, Bjoern; Deschner, James; Gassner, Robert; Butterfield, Timothy A.; Agarwal, Sudha

    2011-01-01

    Chronic inflammation is one of the major causes of cartilage destruction in osteoarthritis. Here, we systematically analyzed the changes in gene expression associated with the progression of cartilage destruction in monoiodoacetate-induced arthritis (MIA) of the rat knee. Sprague Dawley female rats were given intra-articular injection of monoiodoacetate in the knee. The progression of MIA was monitored macroscopically, microscopically and by micro-computed tomography. Grade 1 damage was observed by day 5 post-monoiodoacetate injection, progressively increasing to Grade 2 by day 9, and to Grade 3–3.5 by day 21. Affymetrix GeneChip was utilized to analyze the transcriptome-wide changes in gene expression, and the expression of salient genes was confirmed by real-time-PCR. Functional networks generated by Ingenuity Pathways Analysis (IPA) from the microarray data correlated the macroscopic/histologic findings with molecular interactions of genes/gene products. Temporal changes in gene expression during the progression of MIA were categorized into five major gene clusters. IPA revealed that Grade 1 damage was associated with upregulation of acute/innate inflammatory responsive genes (Cluster I) and suppression of genes associated with musculoskeletal development and function (Cluster IV). Grade 2 damage was associated with upregulation of chronic inflammatory and immune trafficking genes (Cluster II) and downregulation of genes associated with musculoskeletal disorders (Cluster IV). The Grade 3 to 3.5 cartilage damage was associated with chronic inflammatory and immune adaptation genes (Cluster III). These findings suggest that temporal regulation of discrete gene clusters involving inflammatory mediators, receptors, and proteases may control the progression of cartilage destruction. In this process, IL-1β, TNF-α, IL-15, IL-12, chemokines, and NF-κB act as central nodes of the inflammatory networks, regulating catabolic processes. Simultaneously, upregulation of

  14. Intestinal gene expression profiles of piglets benefit from maternal supplementation with a yeast mannan-rich fraction during gestation and lactation.

    PubMed

    Graugnard, D E; Samuel, R S; Xiao, R; Spangler, L F; Brennan, K M

    2015-04-01

    The objective was to study the effect of maternal supplementation with a yeast cell wall-based product containing a mannan-rich fraction (MRF) during gestation and lactation on piglet intestinal gene expression. First parity sows were fed experimental gestation and lactation diets with or without MRF (900 mg/kg). After farrowing, piglets were fostered within treatment, as necessary. Sow and litter production performance data were collected until weaning. On day 10 post farrowing, jejunum samples from piglets were collected for gene expression analysis using the Affymetrix Porcine GeneChip array. Most performance parameters did not differ between the treatments. However, protein (P<0.01), total solids less fat (P<0.03) and the concentration of immunoglobulin G (IgG) in milk were greater (P<0.05) in the MRF-supplemented group. Gene expression results using hierarchical clustering revealed an overall dietary effect. Further analysis elucidated activation of pathways involved in tissue development, functioning and immunity, as well as greater cell proliferation and less migration of cells in the jejunum tissue. In conclusion, feeding the sow MRF during pregnancy and lactation was an effective nutritional strategy to bolster colostrum and milk IgG that are essential for development of piglet immune system and gut. In addition, the gene expression patterns affected by the passive immunity transfer showed indicators that could benefit animal performance long term.

  15. GLAST: gene expression regulation by phorbol esters.

    PubMed

    Espinoza-Rojo, M; López-Bayghen, E; Ortega, A

    2000-08-21

    The gene expression regulation of the Na+-dependent high affinity glutamate/aspartate transporter GLAST expressed in cultured Bergmann glia cells from chick cerebellum was studied. A 679 bp fragment of the chick GLAST cDNA was cloned and sequenced. Specific PCR primers were used to quantify chick GLAST mRNA levels. Treatment of the cells with the Ca2+/diacylglycerol dependent protein kinase C (PKC) activator, phorbol 12-tetradecanoyl-13-acetate (TPA) produced a decrease in transporter mRNA levels, without an effect in its mRNA half life, suggesting a transcriptional down regulation. Activation of the cAMP pathway results in a transient decrease in GLAST mRNA levels, in contrast with the TPA effect. These findings suggest that GLAST expression is under control of distinct signaling pathways.

  16. Differential gene expression in cumulus oocyte complexes collected by ovum pick up from repeat breeder and normally fertile Holstein Friesian heifers.

    PubMed

    Puglisi, Roberto; Cambuli, Caterina; Capoferri, Rossana; Giannino, Laura; Lukaj, Aleksander; Duchi, Roberto; Lazzari, Giovanna; Galli, Cesare; Feligini, Maria; Galli, Andrea; Bongioni, Graziella

    2013-09-01

    The aim of this study was to establish whether perturbed gene expression during cumulus oocyte development causes repeat breeding in cattle. In this study, a repeat breeder was defined as a normal estrous cycling animal that did not become pregnant after three inseminations despite the absence of clinically detectable reproductive disorders. Transcripts of genes extracted from cumulus oocyte complexes (COC) that were collected from three repeat breeder and three normally fertile Holstein Friesian heifers were compared. Up to 40 COC were collected from each heifer by means of repeated sessions of ovum pick up in the absence of hormonal stimulation; immediately plunged into liquid nitrogen; and stored at -80°C until analysis. For each heifer, RNA was extracted from the pooled COC and hybridized on GeneChip(®) Bovine Gene Array (Affymetrix). Analysis of gene expression profiles of repeat breeder and control COC showed that 178 genes were differentially expressed (log2 fold change>1.5). Of these genes, 43 (24%) were up-regulated and 135 (76%) were down-regulated in repeat breeder relative to control heifers. This altered pattern of expression occurred in genes involved in several cellular biological processes and cellular components such as metabolism, angiogenesis, substrate/ion transport, regulation/signaling, cell adhesion and cytoskeleton. From these, 13 genes potentially involved in cumulus oocyte growth were subjected to validation by qRT-PCR and nine genes (annexin A1, ANXA1; lactoferrin, LTF; interferon stimulated exonuclease 20kDa, ISG20/HEM45; oxidized low density lipoprotein receptor 1, OLR1; fatty acid desaturase 2, FADS2; glutathione S-transferase A2 and A4, GSTA2 and GSTA4; glutathione peroxidase 1, GPX1; endothelin receptor type A, EDNRA) were confirmed to be differentially expressed. This study identified potential marker genes for fertility in dairy cattle.

  17. Murine erythropoietin gene: cloning, expression, and human gene homology.

    PubMed Central

    Shoemaker, C B; Mitsock, L D

    1986-01-01

    The gene for murine erythropoietin (EPO) was isolated from a mouse genomic library with a human EPO cDNA probe. Nucleotide sequence analysis permitted the identification of the murine EPO coding sequence and the prediction of the encoded amino acid sequence based on sequence conservation between the mouse and human EPO genes. Both the coding DNA and the amino acid sequences were 80% conserved between the two species. Transformation of COS-1 cells with a mammalian cell expression vector containing the murine EPO coding region resulted in secretion of murine EPO with biological activity on both murine and human erythroid progenitor cells. The transcription start site for the murine EPO gene in kidneys was determined. This permitted tentative identification of the transcription control region. The region included 140 base pairs upstream of the cap site which was over 90% conserved between the murine and human genes. Surprisingly, the first intron and much of the 5'- and 3'-untranslated sequences were also substantially conserved between the genes of the two species. Images PMID:3773894

  18. Identification of common prognostic gene expression signatures with biological meanings from microarray gene expression datasets.

    PubMed

    Yao, Jun; Zhao, Qi; Yuan, Ying; Zhang, Li; Liu, Xiaoming; Yung, W K Alfred; Weinstein, John N

    2012-01-01

    Numerous prognostic gene expression signatures for breast cancer were generated previously with few overlap and limited insight into the biology of the disease. Here we introduce a novel algorithm named SCoR (Survival analysis using Cox proportional hazard regression and Random resampling) to apply random resampling and clustering methods in identifying gene features correlated with time to event data. This is shown to reduce overfitting noises involved in microarray data analysis and discover functional gene sets linked to patient survival. SCoR independently identified a common poor prognostic signature composed of cell proliferation genes from six out of eight breast cancer datasets. Furthermore, a sequential SCoR analysis on highly proliferative breast cancers repeatedly identified T/B cell markers as favorable prognosis factors. In glioblastoma, SCoR identified a common good prognostic signature of chromosome 10 genes from two gene expression datasets (TCGA and REMBRANDT), recapitulating the fact that loss of one copy of chromosome 10 (which harbors the tumor suppressor PTEN) is linked to poor survival in glioblastoma patients. SCoR also identified prognostic genes on sex chromosomes in lung adenocarcinomas, suggesting patient gender might be used to predict outcome in this disease. These results demonstrate the power of SCoR to identify common and biologically meaningful prognostic gene expression signatures.

  19. Identification of Common Prognostic Gene Expression Signatures with Biological Meanings from Microarray Gene Expression Datasets

    PubMed Central

    Yao, Jun; Zhao, Qi; Yuan, Ying; Zhang, Li; Liu, Xiaoming; Yung, W. K. Alfred; Weinstein, John N.

    2012-01-01

    Numerous prognostic gene expression signatures for breast cancer were generated previously with few overlap and limited insight into the biology of the disease. Here we introduce a novel algorithm named SCoR (Survival analysis using Cox proportional hazard regression and Random resampling) to apply random resampling and clustering methods in identifying gene features correlated with time to event data. This is shown to reduce overfitting noises involved in microarray data analysis and discover functional gene sets linked to patient survival. SCoR independently identified a common poor prognostic signature composed of cell proliferation genes from six out of eight breast cancer datasets. Furthermore, a sequential SCoR analysis on highly proliferative breast cancers repeatedly identified T/B cell markers as favorable prognosis factors. In glioblastoma, SCoR identified a common good prognostic signature of chromosome 10 genes from two gene expression datasets (TCGA and REMBRANDT), recapitulating the fact that loss of one copy of chromosome 10 (which harbors the tumor suppressor PTEN) is linked to poor survival in glioblastoma patients. SCoR also identified prognostic genes on sex chromosomes in lung adenocarcinomas, suggesting patient gender might be used to predict outcome in this disease. These results demonstrate the power of SCoR to identify common and biologically meaningful prognostic gene expression signatures. PMID:23029298

  20. High-Frequency Stimulation of the Subthalamic Nucleus Counteracts Cortical Expression of Major Histocompatibility Complex Genes in a Rat Model of Parkinson’s Disease

    PubMed Central

    Grieb, Benjamin; Engler, Gerhard; Sharott, Andrew; von Nicolai, Constantin; Streichert, Thomas; Papageorgiou, Ismini; Schulte, Alexander; Westphal, Manfred; Lamszus, Katrin; Engel, Andreas K.

    2014-01-01

    High-frequency stimulation of the subthalamic nucleus (STN-HFS) is widely used as therapeutic intervention in patients suffering from advanced Parkinson’s disease. STN-HFS exerts a powerful modulatory effect on cortical motor control by orthodromic modulation of basal ganglia outflow and via antidromic activation of corticofugal fibers. However, STN-HFS-induced changes of the sensorimotor cortex are hitherto unexplored. To address this question at a genomic level, we performed mRNA expression analyses using Affymetrix microarray gene chips and real-time RT-PCR in sensorimotor cortex of parkinsonian and control rats following STN-HFS. Experimental parkinsonism was induced in Brown Norway rats by bilateral nigral injections of 6-hydroxydopamine and was assessed histologically, behaviorally, and electrophysiologically. We applied prolonged (23h) unilateral STN-HFS in awake and freely moving animals, with the non-stimulated hemisphere serving as an internal control for gene expression analyses. Gene enrichment analysis revealed strongest regulation in major histocompatibility complex (MHC) related genes. STN-HFS led to a cortical downregulation of several MHC class II (RT1-Da, Db1, Ba, and Cd74) and MHC class I (RT1CE) encoding genes. The same set of genes showed increased expression levels in a comparison addressing the effect of 6-hydroxydopamine lesioning. Hence, our data suggest the possible association of altered microglial activity and synaptic transmission by STN-HFS within the sensorimotor cortex of 6-hydroxydopamine treated rats. PMID:24621597

  1. X chromosome regulation of autosomal gene expression in bovine blastocysts.

    PubMed

    Itoh, Yuichiro; Arnold, Arthur P

    2014-10-01

    Although X chromosome inactivation in female mammals evolved to balance the expression of X chromosome and autosomal genes in the two sexes, female embryos pass through developmental stages in which both X chromosomes are active in somatic cells. Bovine blastocysts show higher expression of many X genes in XX than XY embryos, suggesting that X inactivation is not complete. Here, we reanalyzed bovine blastocyst microarray expression data from a network perspective with a focus on interactions between X chromosome and autosomal genes. Whereas male-to-female ratios of expression of autosomal genes were distributed around a mean of 1, X chromosome genes were clearly shifted towards higher expression in females. We generated gene coexpression networks and identified a major module of genes with correlated gene expression that includes female-biased X genes and sexually dimorphic autosomal genes for which the sexual dimorphism is likely driven by the X genes. In this module, expression of X chromosome genes correlates with autosome genes, more than the expression of autosomal genes with each other. Our study identifies correlated patterns of autosomal and X-linked genes that are likely influenced by the sexual imbalance of X gene expression when X inactivation is inefficient.

  2. Gravity-Induced Gene Expression in Plants.

    NASA Astrophysics Data System (ADS)

    Sederoff, Heike; Heber, Steffen; Howard, Brian; Myburg-Nichols, Henrietta; Hammond, Rebecca; Salinas-Mondragon, Raul; Brown, Christopher S.

    Plants sense changes in their orientation towards the vector of gravity and respond with directional growth. Several metabolites in the signal transduction cascade have been identified. However, very little is known about the interaction between these sensing and signal transduction events and even less is known about their role in the differential growth response. Gravity induced changes in transcript abundance have been identified in Arabidopsis whole seedlings and root apices (Moseyko et al. 2002; Kimbrough et al. 2004). Gravity induced transcript abundance changes can be observed within less than 1 min after stimulation (Salinas-Mondragon et al. 2005). Gene expression however requires not only transcription but also translation of the mRNA. Translation can only occur when mRNA is associated with ribosomes, even though not all mRNA associated with ribosomes is actively translated. To approximate translational capacity we quantified whole genome transcript abundances in corn stem pulvini during the first hour after gravity stimulation in total and poly-ribosomal fractions. As in Arabidopsis root apices, transcript abundances of several clusters of genes responded to gravity stimulation. The vast majority of these transcripts were also found to associate with polyribosomes in the same temporal and quantitative pattern. These genes are transcriptionally regulated by gravity stimulation, but do not exhibit translational regulation. However, a small group of genes showed increased transcriptional regulation after gravity stimulation, but no association with polysomes. These transcripts likely are translationally repressed. The mechanism of translational repression for these transcripts is unknown. Based on the hypothesis that the genes essential for gravitropic responses should be expressed in most or all species, we compared the temporal gravity induced expression pattern of all orthologs identified between maize and Arabidopsis. A small group of genes showed high

  3. Cigarette smoke-induced emphysema in A/J mice is associated with pulmonary oxidative stress, apoptosis of lung cells, and global alterations in gene expression

    PubMed Central

    Rangasamy, Tirumalai; Misra, Vikas; Zhen, Lijie; Tankersley, Clarke G.; Tuder, Rubin M.; Biswal, Shyam

    2009-01-01

    Cigarette smoking is the major risk factor for developing chronic obstructive pulmonary disease, the fourth leading cause of deaths in the United States. Despite recent advances, the molecular mechanisms involved in the initiation and progression of this disease remain elusive. We used Affymetrix Gene Chip arrays to determine the temporal alterations in global gene expression during the progression of pulmonary emphysema in A/J mice. Chronic cigarette smoke (CS) exposure caused pulmonary emphysema in A/J mice, which was associated with pronounced bronchoalveolar inflammation, enhanced oxidative stress, and increased apoptosis of alveolar septal cells. Microarray analysis revealed the upregulation of 1,190, 715, 260, and 246 genes and the downregulation of 1,840, 730, 442, and 236 genes in the lungs of mice exposed to CS for 5 h, 8 days, and 1.5 and 6 mo, respectively. Most of the genes belong to the functional categories of phase I genes, Nrf2-regulated antioxidant and phase II genes, phase III detoxification genes, and others including immune/inflammatory response genes. Induction of the genes encoding multiple phase I enzymes was markedly higher in the emphysematous lungs, whereas reduced expression of various cytoprotective genes constituting ubiquitin-proteasome complex, cell survival pathways, solute carriers and transporters, transcription factors, and Nrf2-regulated antioxidant and phase II-responsive genes was noted. Our data indicate that the progression of CS-induced emphysema is associated with a steady decline in the expression of various genes involved in multiple pathways in the lungs of A/J mice. Many of the genes discovered in this study could rationally play an important role in the susceptibility to CS-induced emphysema. PMID:19286929

  4. A gene expression signature for insulin resistance.

    PubMed

    Konstantopoulos, Nicky; Foletta, Victoria C; Segal, David H; Shields, Katherine A; Sanigorski, Andrew; Windmill, Kelly; Swinton, Courtney; Connor, Tim; Wanyonyi, Stephen; Dyer, Thomas D; Fahey, Richard P; Watt, Rose A; Curran, Joanne E; Molero, Juan-Carlos; Krippner, Guy; Collier, Greg R; James, David E; Blangero, John; Jowett, Jeremy B; Walder, Ken R

    2011-02-11

    Insulin resistance is a heterogeneous disorder caused by a range of genetic and environmental factors, and we hypothesize that its etiology varies considerably between individuals. This heterogeneity provides significant challenges to the development of effective therapeutic regimes for long-term management of type 2 diabetes. We describe a novel strategy, using large-scale gene expression profiling, to develop a gene expression signature (GES) that reflects the overall state of insulin resistance in cells and patients. The GES was developed from 3T3-L1 adipocytes that were made "insulin resistant" by treatment with tumor necrosis factor-α (TNF-α) and then reversed with aspirin and troglitazone ("resensitized"). The GES consisted of five genes whose expression levels best discriminated between the insulin-resistant and insulin-resensitized states. We then used this GES to screen a compound library for agents that affected the GES genes in 3T3-L1 adipocytes in a way that most closely resembled the changes seen when insulin resistance was successfully reversed with aspirin and troglitazone. This screen identified both known and new insulin-sensitizing compounds including nonsteroidal anti-inflammatory agents, β-adrenergic antagonists, β-lactams, and sodium channel blockers. We tested the biological relevance of this GES in participants in the San Antonio Family Heart Study (n = 1,240) and showed that patients with the lowest GES scores were more insulin resistant (according to HOMA_IR and fasting plasma insulin levels; P < 0.001). These findings show that GES technology can be used for both the discovery of insulin-sensitizing compounds and the characterization of patients into subtypes of insulin resistance according to GES scores, opening the possibility of developing a personalized medicine approach to type 2 diabetes.

  5. Early changes in gene expression induced by blue light irradiation of A2E-laden retinal pigment epithelial cells

    PubMed Central

    van der Burght, Barbro W.; Hansen, Morten; Olsen, Jørgen; Zhou, Jilin; Wu, Yalin; Nissen, Mogens H.; Sparrow, Janet R.

    2016-01-01

    Purpose Accumulation of bisretinoids as lipofuscin in retinal pigment epithelial (RPE) cells is implicated in the pathogenesis of some blinding diseases including age-related macular degeneration (AMD). To identify genes whose expression may change under conditions of bisretinoid accumulation, we investigated the differential gene expression in RPE cells that had accumulated the lipofuscin fluorophore A2E and were exposed to blue light (430 nm). Methods A2E-laden RPE cells were exposed to blue light (A2E/430 nm) at various time intervals. Cell death was quantified using Dead Red staining, and RNA levels for the entire genome was determined using DNA microarrays (Affymetrix GeneChip Human Genome 2.0 Plus). Array results for selected genes were confirmed by real-time reverse-transcriptase polymerase chain reaction. Results Principal component analysis revealed that the A2E-laden RPE cells irradiated with blue light were clearly distinguishable from the control samples. We found differential regulation of genes belonging to the following functional groups: transcription factors, stress response, apoptosis and immune response. Among the last mentioned were downregulation of four genes that coded for proteins that have an inhibitory effect on the complement cascade: (complement factor H, complement factor H-related 1, complement factor I and vitronectin) and of two belonging to the classical pathway (complement component 1, s subcomponent and complement component 1, r subcomponent). Conclusion This study demonstrates that blue light irradiation of A2E-laden RPE cells can alter the transcription of genes belonging to different functional pathways including stress response, apoptosis and the immune response. We suggest that these molecules may be associated to the pathogenesis of AMD and can potentially serve as future therapeutic targets. PMID:23742627

  6. Covariance Structure Models for Gene Expression Microarray Data

    ERIC Educational Resources Information Center

    Xie, Jun; Bentler, Peter M.

    2003-01-01

    Covariance structure models are applied to gene expression data using a factor model, a path model, and their combination. The factor model is based on a few factors that capture most of the expression information. A common factor of a group of genes may represent a common protein factor for the transcript of the co-expressed genes, and hence, it…

  7. Analysis of changes in hepatic gene expression in a murine model of tolerance to acetaminophen hepatotoxicity (autoprotection)

    SciTech Connect

    O'Connor, Meeghan A.; Koza-Taylor, Petra; Campion, Sarah N.; Aleksunes, Lauren M.; Gu, Xinsheng; Enayetallah, Ahmed E.; Lawton, Michael P.; Manautou, José E.

    2014-01-01

    Pretreatment of mice with a low hepatotoxic dose of acetaminophen (APAP) results in resistance to a subsequent, higher dose of APAP. This mouse model, termed APAP autoprotection was used here to identify differentially expressed genes and cellular pathways that could contribute to this development of resistance to hepatotoxicity. Male C57BL/6J mice were pretreated with APAP (400 mg/kg) and then challenged 48 h later with 600 mg APAP/kg. Livers were obtained 4 or 24 h later and total hepatic RNA was isolated and hybridized to Affymetrix Mouse Genome MU430{sub 2} GeneChip. Statistically significant genes were determined and gene expression changes were also interrogated using the Causal Reasoning Engine (CRE). Extensive literature review narrowed our focus to methionine adenosyl transferase-1 alpha (MAT1A), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), flavin-containing monooxygenase 3 (Fmo3) and galectin-3 (Lgals3). Down-regulation of MAT1A could lead to decreases in S-adenosylmethionine (SAMe), which is known to protect against APAP toxicity. Nrf2 activation is expected to play a role in protective adaptation. Up-regulation of Lgals3, one of the genes supporting the Nrf2 hypothesis, can lead to suppression of apoptosis and reduced mitochondrial dysfunction. Fmo3 induction suggests the involvement of an enzyme not known to metabolize APAP in the development of tolerance to APAP toxicity. Subsequent quantitative RT-PCR and immunochemical analysis confirmed the differential expression of some of these genes in the APAP autoprotection model. In conclusion, our genomics strategy identified cellular pathways that might further explain the molecular basis for APAP autoprotection. - Highlights: • Differential expression of genes in mice resistant to acetaminophen hepatotoxicity. • Increased gene expression of Flavin-containing monooxygenase 3 and Galectin-3. • Decrease in MAT1A expression and compensatory hepatocellular regeneration. • Two distinct gene

  8. Differential Genes Expression between Fertile and Infertile Spermatozoa Revealed by Transcriptome Analysis

    PubMed Central

    Bansal, Sandeep Kumar; Gupta, Nishi; Sankhwar, Satya Narayan; Rajender, Singh

    2015-01-01

    Background It was believed earlier that spermatozoa have no traces of RNA because of loss of most of the cytoplasm. Recent studies have revealed the presence of about 3000 different kinds of mRNAs in ejaculated spermatozoa. However, the correlation of transcriptome profile with infertility remains obscure. Methods Total RNA from sperm (after exclusion of somatic cells) of 60 men consisting of individuals with known fertility (n=20), idiopathic infertility (normozoospermic patients, n=20), and asthenozoospermia (n=20) was isolated. After RNA quality check on Bioanalyzer, AffymetrixGeneChip Human Gene 1.0 ST Array was used for expression profiling, which consisted of >30,000 coding transcripts and >11,000 long intergenic non-coding transcripts. Results Comparison between all three groups revealed that two thousand and eighty one transcripts were differentially expressed. Analysis of these transcripts showed that some transcripts [ribosomal proteins (RPS25, RPS11, RPS13, RPL30, RPL34, RPL27, RPS5), HINT1, HSP90AB1, SRSF9, EIF4G2, ILF2] were up-regulated in the normozoospermic group, but down-regulated in the asthenozoospermic group in comparison to the control group. Some transcripts were specific to the normozoospermic group (up-regulated: CAPNS1, FAM153C, ARF1, CFL1, RPL19, USP22; down-regulated: ZNF90, SMNDC1, c14orf126, HNRNPK), while some were specific to the asthenozoospermic group (up-regulated: RPL24, HNRNPM, RPL4, PRPF8, HTN3, RPL11, RPL28, RPS16, SLC25A3, C2orf24, RHOA, GDI2, NONO, PARK7; down-regulated: HNRNPC, SMARCAD1, RPS24, RPS24, RPS27A, KIFAP3). A number of differentially expressed transcripts in spermatozoa were related to reproduction (n = 58) and development (n= 210). Some of these transcripts were related to heat shock proteins (DNAJB4, DNAJB14), testis specific genes (TCP11, TESK1, TSPYL1, ADAD1), and Y-chromosome genes (DAZ1, TSPYL1). Conclusion A complex RNA population in spermatozoa consisted of coding and non-coding RNAs. A number of

  9. The effect of enterotoxigenic Escherichia coli F4ab,ac on early-weaned piglets: a gene expression study.

    PubMed

    Schroyen, M; Goddeeris, B M; Stinckens, A; Verhelst, R; Janssens, S; Cox, E; Georges, M; Niewold, T; Buys, N

    2013-03-15

    Diarrhoea in neonatal and early-weaned piglets due to enterotoxigenic Escherichia coli-F4 (ETEC-F4) is an important problem in the pig farming industry. There is substantial evidence for a genetic basis for susceptibility to ETEC-F4 since not all pigs suffer from diarrhoea after an ETEC-F4 infection. A region on SSC13 has been found to be in close linkage to the susceptibility of piglets for ETEC-F4ab,ac. Potential candidate genes on SSC13 have been examined and although some polymorphisms were found to be in linkage disequilibrium with the phenotype, the causative mutation has not yet been found. In this study we are looking at the expression of porcine genes in relation to ETEC-F4ab,ac. With the aid of the Affymetrix GeneChip Porcine Genome Array we were able to find differentially expressed genes between ETEC-F4ab,ac receptor positive (Fab,acR(+)) piglets without diarrhoea and F4ab,acR(+) piglets with diarrhoea or F4ab,acR(-) animals. Since the susceptibility to ETEC-F4ab,ac was described as a Mendelian trait, it is not so surprisingly that only two differentially expressed genes, transferrin receptor (TFRC) and trefoil factor 1 (TFF1), came out of the analysis. Although both genes could pass for functional candidate genes only TFRC also mapped to the region on SSC13 associated with susceptibility for ETEC-F4, which makes TFRC a positional functional candidate gene. Validation by qRT-PCR confirmed the differential expression of TFRC and TFF1. In piglets without diarrhoea, the expression of both genes was higher in F4ab,acR(+) than in F4ab,acR(-) piglets. Similarly, TFRC and TFF1 expression in F4ab,acR(+) piglets without diarrhoea was also higher than in F4ab,acR(+) piglets with diarrhoea. Consequently, although both genes might not play a role as receptor for F4 fimbriae, they could be of great importance during an ETEC-F4 outbreak. An upregulation of TFRC can be a consequence of the piglets ability to raise an effective immune response. An elevation of TFF1, a

  10. Gene Expression in First Trimester Preeclampsia Placenta

    PubMed Central

    Founds, Sandra A.; Terhorst, Lauren A.; Conrad, Kirk P.; Hogge, W. Allen; Jeyabalan, Arun; Conley, Yvette P.

    2013-01-01

    Background The goal of this study was to further validate eight candidate genes identified in a microarray analysis of first trimester placentas in preeclampsia. Material and method Surplus chorionic villus sampling (CVS) specimens of 4 women subsequently diagnosed with preeclampsia (PE) and 8 control women (C) without preeclampsia analyzed previously by microarray and 24 independent additional control samples (AS) were submitted for confirmatory studies by quantitative real-time polymerase chain reaction (qRT-PCR). Results Downregulation was significant in FSTL3 in PE as compared to C and AS (p = .04). PAEP was downregulated, but the difference was only significant between C and AS (p = .002) rather than between PE and either of the control groups. Expression levels for CFH, EPAS1, IGFBP1, MMP12, and SEMA3C were not statistically different among groups, but trends were consistent with microarray results; there was no anti-correlation. S100A8 was not measurable in all samples, probably because different probes and primers were needed. Conclusions This study corroborates reduced FSTL3 expression in the first trimester of preeclampsia. Nonsignificant trends in the other genes may require follow-up in studies powered for medium or medium/large effect sizes. qRT-PCR verification of the prior microarray of CVS may support the placental origins of preeclampsia hypothesis. Replication is needed for the candidate genes as potential biomarkers of susceptibility, early detection, and/or individualized care of maternal–infant preeclampsia. PMID:21044967

  11. Nuclear AXIN2 represses MYC gene expression

    SciTech Connect

    Rennoll, Sherri A.; Konsavage, Wesley M.; Yochum, Gregory S.

    2014-01-03

    Highlights: •AXIN2 localizes to cytoplasmic and nuclear compartments in colorectal cancer cells. •Nuclear AXIN2 represses the activity of Wnt-responsive luciferase reporters. •β-Catenin bridges AXIN2 to TCF transcription factors. •AXIN2 binds the MYC promoter and represses MYC gene expression. -- Abstract: The β-catenin transcriptional coactivator is the key mediator of the canonical Wnt signaling pathway. In the absence of Wnt, β-catenin associates with a cytosolic and multi-protein destruction complex where it is phosphorylated and targeted for proteasomal degradation. In the presence of Wnt, the destruction complex is inactivated and β-catenin translocates into the nucleus. In the nucleus, β-catenin binds T-cell factor (TCF) transcription factors to activate expression of c-MYC (MYC) and Axis inhibition protein 2 (AXIN2). AXIN2 is a member of the destruction complex and, thus, serves in a negative feedback loop to control Wnt/β-catenin signaling. AXIN2 is also present in the nucleus, but its function within this compartment is unknown. Here, we demonstrate that AXIN2 localizes to the nuclei of epithelial cells within normal and colonic tumor tissues as well as colorectal cancer cell lines. In the nucleus, AXIN2 represses expression of Wnt/β-catenin-responsive luciferase reporters and forms a complex with β-catenin and TCF. We demonstrate that AXIN2 co-occupies β-catenin/TCF complexes at the MYC promoter region. When constitutively localized to the nucleus, AXIN2 alters the chromatin structure at the MYC promoter and directly represses MYC gene expression. These findings suggest that nuclear AXIN2 functions as a rheostat to control MYC expression in response to Wnt/β-catenin signaling.

  12. Molecular mechanisms of curcumin action: gene expression.

    PubMed

    Shishodia, Shishir

    2013-01-01

    Curcumin derived from the tropical plant Curcuma longa has a long history of use as a dietary agent, food preservative, and in traditional Asian medicine. It has been used for centuries to treat biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders, rheumatism, and sinusitis. The preventive and therapeutic properties of curcumin are associated with its antioxidant, anti-inflammatory, and anticancer properties. Extensive research over several decades has attempted to identify the molecular mechanisms of curcumin action. Curcumin modulates numerous molecular targets by altering their gene expression, signaling pathways, or through direct interaction. Curcumin regulates the expression of inflammatory cytokines (e.g., TNF, IL-1), growth factors (e.g., VEGF, EGF, FGF), growth factor receptors (e.g., EGFR, HER-2, AR), enzymes (e.g., COX-2, LOX, MMP9, MAPK, mTOR, Akt), adhesion molecules (e.g., ELAM-1, ICAM-1, VCAM-1), apoptosis related proteins (e.g., Bcl-2, caspases, DR, Fas), and cell cycle proteins (e.g., cyclin D1). Curcumin modulates the activity of several transcription factors (e.g., NF-κB, AP-1, STAT) and their signaling pathways. Based on its ability to affect multiple targets, curcumin has the potential for the prevention and treatment of various diseases including cancers, arthritis, allergies, atherosclerosis, aging, neurodegenerative disease, hepatic disorders, obesity, diabetes, psoriasis, and autoimmune diseases. This review summarizes the molecular mechanisms of modulation of gene expression by curcumin.

  13. Molecular mechanisms of curcumin action: gene expression.

    PubMed

    Shishodia, Shishir

    2013-01-01

    Curcumin derived from the tropical plant Curcuma longa has a long history of use as a dietary agent, food preservative, and in traditional Asian medicine. It has been used for centuries to treat biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders, rheumatism, and sinusitis. The preventive and therapeutic properties of curcumin are associated with its antioxidant, anti-inflammatory, and anticancer properties. Extensive research over several decades has attempted to identify the molecular mechanisms of curcumin action. Curcumin modulates numerous molecular targets by altering their gene expression, signaling pathways, or through direct interaction. Curcumin regulates the expression of inflammatory cytokines (e.g., TNF, IL-1), growth factors (e.g., VEGF, EGF, FGF), growth factor receptors (e.g., EGFR, HER-2, AR), enzymes (e.g., COX-2, LOX, MMP9, MAPK, mTOR, Akt), adhesion molecules (e.g., ELAM-1, ICAM-1, VCAM-1), apoptosis related proteins (e.g., Bcl-2, caspases, DR, Fas), and cell cycle proteins (e.g., cyclin D1). Curcumin modulates the activity of several transcription factors (e.g., NF-κB, AP-1, STAT) and their signaling pathways. Based on its ability to affect multiple targets, curcumin has the potential for the prevention and treatment of various diseases including cancers, arthritis, allergies, atherosclerosis, aging, neurodegenerative disease, hepatic disorders, obesity, diabetes, psoriasis, and autoimmune diseases. This review summarizes the molecular mechanisms of modulation of gene expression by curcumin. PMID:22996381

  14. Combined clustering models for the analysis of gene expression

    SciTech Connect

    Angelova, M. Ellman, J.

    2010-02-15

    Clustering has become one of the fundamental tools for analyzing gene expression and producing gene classifications. Clustering models enable finding patterns of similarity in order to understand gene function, gene regulation, cellular processes and sub-types of cells. The clustering results however have to be combined with sequence data or knowledge about gene functionality in order to make biologically meaningful conclusions. In this work, we explore a new model that integrates gene expression with sequence or text information.

  15. Identification of differentially expressed thyroid hormone responsive genes from the brain of the Mexican Axolotl (Ambystoma mexicanum).

    PubMed

    Huggins, P; Johnson, C K; Schoergendorfer, A; Putta, S; Bathke, A C; Stromberg, A J; Voss, S R

    2012-01-01

    The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p<0.05, fold change >1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian.

  16. Drinking-Water Arsenic Exposure Modulates Gene Expression in Human Lymphocytes from a U.S. Population

    PubMed Central

    Andrew, Angeline S.; Jewell, David A.; Mason, Rebecca A.; Whitfield, Michael L.; Moore, Jason H.; Karagas, Margaret R.

    2008-01-01

    Background Arsenic exposure impairs development and can lead to cancer, cardiovascular disease, and diabetes. The mechanism underlying these effects remains unknown. Primarily because of geologic sources of contamination, drinking-water arsenic levels are above the current recommended maximum contaminant level of 10 μg/L in the northeastern, western, and north central regions of the United States. Objectives We investigated the effects of arsenic exposure, defined by internal biomarkers at levels relevant to the United States and similarly exposed populations, on gene expression. Methods We conducted separate Affymetrix microarray-based genomewide analyses of expression patterns. Peripheral blood lymphocyte samples from 21 controls interviewed (1999–2002) as part of a case–control study in New Hampshire were selected based on high- versus low-level arsenic exposure levels. Results The biologic functions of the transcripts that showed statistically significant abundance differences between high- and low-arsenic exposure groups included an overrepresentation of genes involved in defense response, immune function, cell growth, apoptosis, regulation of cell cycle, T-cell receptor signaling pathway, and diabetes. Notably, the high-arsenic exposure group exhibited higher levels of several killer cell immunoglobulin-like receptors that inhibit natural killer cell activity. Conclusions These findings define biologic changes that occur with chronic arsenic exposure in humans and provide leads and potential targets for understanding and monitoring the pathogenesis of arsenic-induced diseases. PMID:18414638

  17. A roadmap for zinc trafficking in the developing barley grain based on laser capture microdissection and gene expression profiling

    PubMed Central

    Tauris, Birgitte; Borg, Søren; Gregersen, Per L.; Holm, Preben B.

    2009-01-01

    Nutrients destined for the developing cereal grain encounter several restricting barriers on their path towards their final storage sites in the grain. In order to identify transporters and chelating agents that may be involved in transport and deposition of zinc in the barley grain, expression profiles have been generated of four different tissue types: the transfer cells, the aleurone layer, the endosperm, and the embryo. Cells from these tissues were isolated with the ‘laser capture microdissection’ technology and the extracted RNA was subjected to three rounds of T7-based amplification. The amplified RNA was subsequently hybridized to Affymetrix 22K Barley GeneChips. Due to the short average length of the amplified transcripts and the positioning of numerous probe sets at locations more than 400 base pairs (bp) from the poly(A)-tail, a normalization approach was used where the probe positions were taken into account. On the basis of the expression levels of a number of metal homeostasis genes, a working model is proposed for the translocation of zinc from the phloem to the storage sites in the developing grain. PMID:19297552

  18. Differential gene expression profiling of mouse skin after sulfur mustard exposure: Extended time response and inhibitor effect

    SciTech Connect

    Gerecke, Donald R. Chen Minjun; Isukapalli, Sastry S.; Gordon, Marion K.; Chang, Y.-C.; Tong Weida; Androulakis, Ioannis P.; Georgopoulos, Panos G.

    2009-01-15

    Sulfur mustard (HD, SM), is a chemical warfare agent that within hours causes extensive blistering at the dermal-epidermal junction of skin. To better understand the progression of SM-induced blistering, gene expression profiling for mouse skin was performed after a single high dose of SM exposure. Punch biopsies of mouse ears were collected at both early and late time periods following SM exposure (previous studies only considered early time periods). The biopsies were examined for pathological disturbances and the samples further assayed for gene expression profiling using the Affymetrix microarray analysis system. Principal component analysis and hierarchical cluster analysis of the differently expressed genes, performed with ArrayTrack showed clear separation of the various groups. Pathway analysis employing the KEGG library and Ingenuity Pathway Analysis (IPA) indicated that cytokine-cytokine receptor interaction, cell adhesion molecules (CAMs), and hematopoietic cell lineage are common pathways affected at different time points. Gene ontology analysis identified the most significantly altered biological processes as the immune response, inflammatory response, and chemotaxis; these findings are consistent with other reported results for shorter time periods. Selected genes were chosen for RT-PCR verification and showed correlations in the general trends for the microarrays. Interleukin 1 beta was checked for biological analysis to confirm the presence of protein correlated to the corresponding microarray data. The impact of a matrix metalloproteinase inhibitor, MMP-2/MMP-9 inhibitor I, against SM exposure was assessed. These results can help in understanding the molecular mechanism of SM-induced blistering, as well as to test the efficacy of different inhibitors.

  19. Differential gene expression profiling of mouse skin after sulfur mustard exposure: Extended time response and inhibitor effect

    PubMed Central

    Gerecke, Donald R.; Chen, Minjun; Isukapalli, Sastry S.; Gordon, Marion K.; Chang, Yoke-Chen; Tong, Weida; Androulakis, Ioannis P.; Georgopoulos, Panos G.

    2011-01-01

    Sulfur mustard (HD, SM), is a chemical warfare agent that within hours causes extensive blistering at the dermal–epidermal junction of skin. To better understand the progression of SM-induced blistering, gene expression profiling for mouse skin was performed after a single high dose of SM exposure. Punch biopsies of mouse ears were collected at both early and late time periods following SM exposure (previous studies only considered early time periods). The biopsies were examined for pathological disturbances and the samples further assayed for gene expression profiling using the Affymetrix microarray analysis system. Principal component analysis and hierarchical cluster analysis of the differently expressed genes, performed with ArrayTrack showed clear separation of the various groups. Pathway analysis employing the KEGG library and Ingenuity Pathway Analysis (IPA) indicated that cytokine–cytokine receptor interaction, cell adhesion molecules (CAMs), and hematopoietic cell lineage are common pathways affected at different time points. Gene ontology analysis identified the most significantly altered biological processes as the immune response, inflammatory response, and chemotaxis; these findings are consistent with other reported results for shorter time periods. Selected genes were chosen for RT-PCR verification and showed correlations in the general trends for the microarrays. Interleukin 1 beta was checked for biological analysis to confirm the presence of protein correlated to the corresponding microarray data. The impact of a matrix metalloproteinase inhibitor, MMP-2/MMP-9 inhibitor I, against SM exposure was assessed. These results can help in understanding the molecular mechanism of SM-induced blistering, as well as to test the efficacy of different inhibitors. PMID:18955075

  20. Using PCR to Target Misconceptions about Gene Expression

    PubMed Central

    Wright, Leslie K.; Newman, Dina L.

    2013-01-01

    We present a PCR-based laboratory exercise that can be used with first- or second-year biology students to help overcome common misconceptions about gene expression. Biology students typically do not have a clear understanding of the difference between genes (DNA) and gene expression (mRNA/protein) and often believe that genes exist in an organism or cell only when they are expressed. This laboratory exercise allows students to carry out a PCR-based experiment designed to challenge their misunderstanding of the difference between genes and gene expression. Students first transform E. coli with an inducible GFP gene containing plasmid and observe induced and un-induced colonies. The following exercise creates cognitive dissonance when actual PCR results contradict their initial (incorrect) predictions of the presence of the GFP gene in transformed cells. Field testing of this laboratory exercise resulted in learning gains on both knowledge and application questions on concepts related to genes and gene expression. PMID:23858358

  1. Development and application of a 6.5 million feature Affymetrix Genechip® for massively parallel discovery of single position polymorphisms in lettuce (Lactuca spp.)

    PubMed Central

    2012-01-01

    Background High-resolution genetic maps are needed in many crops to help characterize the genetic diversity that determines agriculturally important traits. Hybridization to microarrays to detect single feature polymorphisms is a powerful technique for marker discovery and genotyping because of its highly parallel nature. However, microarrays designed for gene expression analysis rarely provide sufficient gene coverage for optimal detection of nucleotide polymorphisms, which limits utility in species with low rates of polymorphism such as lettuce (Lactuca sativa). Results We developed a 6.5 million feature Affymetrix GeneChip® for efficient polymorphism discovery and genotyping, as well as for analysis of gene expression in lettuce. Probes on the microarray were designed from 26,809 unigenes from cultivated lettuce and an additional 8,819 unigenes from four related species (L. serriola, L. saligna, L. virosa and L. perennis). Where possible, probes were tiled with a 2 bp stagger, alternating on each DNA strand; providing an average of 187 probes covering approximately 600 bp for each of over 35,000 unigenes; resulting in up to 13 fold redundancy in coverage per nucleotide. We developed protocols for hybridization of genomic DNA to the GeneChip® and refined custom algorithms that utilized coverage from multiple, high quality probes to detect single position polymorphisms in 2 bp sliding windows across each unigene. This allowed us to detect greater than 18,000 polymorphisms between the parental lines of our core mapping population, as well as numerous polymorphisms between cultivated lettuce and wild species in the lettuce genepool. Using marker data from our diversity panel comprised of 52 accessions from the five species listed above, we were able to separate accessions by species using both phylogenetic and principal component analyses. Additionally, we estimated the diversity between different types of cultivated lettuce and distinguished morphological types

  2. Inferring gene expression dynamics via functional regression analysis

    PubMed Central

    Müller, Hans-Georg; Chiou, Jeng-Min; Leng, Xiaoyan

    2008-01-01

    Background Temporal gene expression profiles characterize the time-dynamics of expression of specific genes and are increasingly collected in current gene expression experiments. In the analysis of experiments where gene expression is obtained over the life cycle, it is of interest to relate temporal patterns of gene expression associated with different developmental stages to each other to study patterns of long-term developmental gene regulation. We use tools from functional data analysis to study dynamic changes by relating temporal gene expression profiles of different developmental stages to each other. Results We demonstrate that functional regression methodology can pinpoint relationships that exist between temporary gene expression profiles for different life cycle phases and incorporates dimension reduction as needed for these high-dimensional data. By applying these tools, gene expression profiles for pupa and adult phases are found to be strongly related to the profiles of the same genes obtained during the embryo phase. Moreover, one can distinguish between gene groups that exhibit relationships with positive and others with negative associations between later life and embryonal expression profiles. Specifically, we find a positive relationship in expression for muscle development related genes, and a negative relationship for strictly maternal genes for Drosophila, using temporal gene expression profiles. Conclusion Our findings point to specific reactivation patterns of gene expression during the Drosophila life cycle which differ in characteristic ways between various gene groups. Functional regression emerges as a useful tool for relating gene expression patterns from different developmental stages, and avoids the problems with large numbers of parameters and multiple testing that affect alternative approaches. PMID:18226220

  3. TNF-α gene polymorphisms and expression.

    PubMed

    El-Tahan, Radwa R; Ghoneim, Ahmed M; El-Mashad, Noha

    2016-01-01

    Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine with an important role in the pathogenesis of several diseases. Its encoding gene is located in the short arm of chromosome 6 in the major histocompatibility complex class III region. Most of the TNF-α gene polymorphisms are located in its promoter region and they are thought to affect the susceptibility and/or severity of different human diseases. This review summarizes the data related to the association between TNF-α gene and its receptor polymorphisms, and the development of autoimmune diseases. Among these polymorphisms the -308G/A TNF-α promotor polymorphism has been associated several times with the the development of autoimmune diseases, however some discrepant results have been recorded. The other TNF-α gene polymorphisms had little or no association with autoimmune diseases. Current results about the molecules controlling TNF-α expression are also presented. The discrepancy between different records could be related partly to either the differences in the ethnic origin or number of the studied individuals, or the abundance and activation of other molecules that interact with the TNF-α promotor region or other elements. PMID:27652081

  4. Hyperbaric oxygen treatment induces antioxidant gene expression.

    PubMed

    Godman, Cassandra A; Joshi, Rashmi; Giardina, Charles; Perdrizet, George; Hightower, Lawrence E

    2010-06-01

    Although the underlying molecular causes of aging are not entirely clear, hormetic agents like exercise, heat, and calorie restriction may generate a mild pro-oxidant stress that induces cell protective responses to promote healthy aging. As an individual ages, many cellular and physiological processes decline, including wound healing and reparative angiogenesis. This is particularly critical in patients with chronic non-healing wounds who tend to be older. We are interested in the potential beneficial effects of hyperbaric oxygen as a mild hormetic stress on human microvascular endothelial cells. We analyzed global gene expression changes in human endothelial cells following a hyperbaric exposure comparable to a clinical treatment. Our analysis revealed an upregulation of antioxidant, cytoprotective, and immediate early genes. This increase coincided with an increased resistance to a lethal oxidative stress. Our data indicate that hyperbaric oxygen can induce protection against oxidative insults in endothelial cells and may provide an easily administered hormetic treatment to help promote healthy aging.

  5. Expressing exogenous genes in newts by transgenesis.

    PubMed

    Casco-Robles, Martin Miguel; Yamada, Shouta; Miura, Tomoya; Nakamura, Kenta; Haynes, Tracy; Maki, Nobuyasu; Del Rio-Tsonis, Katia; Tsonis, Panagiotis A; Chiba, Chikafumi

    2011-05-01

    The great regenerative abilities of newts provide the impetus for studies at the molecular level. However, efficient methods for gene regulation have historically been quite limited. Here we describe a protocol for transgenically expressing exogenous genes in the newt Cynops pyrrhogaster. This method is simple: a reaction mixture of I-SceI meganuclease and a plasmid DNA carrying a transgene cassette flanked by the enzyme recognition sites is directly injected into fertilized eggs. The protocol achieves a high efficiency of transgenesis, comparable to protocols used in other animal systems, and it provides a practical number of transgenic newts (∼20% of injected embryos) that survive beyond metamorphosis and that can be applied to regenerative studies. The entire protocol for obtaining transgenic adult newts takes 4-5 months.

  6. Retrotransposons as regulators of gene expression.

    PubMed

    Elbarbary, Reyad A; Lucas, Bronwyn A; Maquat, Lynne E

    2016-02-12

    Transposable elements (TEs) are both a boon and a bane to eukaryotic organisms, depending on where they integrate into the genome and how their sequences function once integrated. We focus on two types of TEs: long interspersed elements (LINEs) and short interspersed elements (SINEs). LINEs and SINEs are retrotransposons; that is, they transpose via an RNA intermediate. We discuss how LINEs and SINEs have expanded in eukaryotic genomes and contribute to genome evolution. An emerging body of evidence indicates that LINEs and SINEs function to regulate gene expression by affecting chromatin structure, gene transcription, pre-mRNA processing, or aspects of mRNA metabolism. We also describe how adenosine-to-inosine editing influences SINE function and how ongoing retrotransposition is countered by the body's defense mechanisms.

  7. Approaches for gene targeting and targeted gene expression in plants.

    PubMed

    Husaini, Amjad Masood; Rashid, Zerka; Mir, Reyaz-ul Rouf; Aquil, Bushra

    2011-01-01

    Transgenic science and technology are fundamental to state-of-the-art plant molecular genetics and crop improvement. The new generation of technology endeavors to introduce genes 'stably' into 'site-specific' locations and in 'single copy' without the integration of extraneous vector 'backbone' sequences or selectable markers and with a 'predictable and consistent' expression. Several similar strategies and technologies, which can push the development of 'smart' genetically modified plants with desirable attributes, as well as enhance their consumer acceptability, are discussed in this review.

  8. Gene expression profiles in human HepG2 cells treated with extracts of the Tamarindus indica fruit pulp.

    PubMed

    Razali, Nurhanani; Aziz, Azlina A; Junit, Sarni M

    2010-12-01

    Tamarindus indicaL. (T. indica) or locally known as asam jawa belongs to the family of Leguminosae. The fruit pulp had been reported to have antioxidant activities and possess hypolipidaemic effects. In this study, we attempted to investigate the gene expression patterns in human hepatoma HepG2 cell line in response to treatment with low concentration of the fruit pulp extracts. Microarray analysis using Affymetrix Human Genome 1.0 S.T arrays was used in the study. Microarray data were validated using semi-quantitative RT-PCR and real-time RT-PCR. Amongst the significantly up-regulated genes were those that code for the metallothioneins (MT1M, MT1F, MT1X) and glutathione S-transferases (GSTA1, GSTA2, GST02) that are involved in stress response. APOA4, APOA5, ABCG5 and MTTP genes were also significantly regulated that could be linked to hypolipidaemic activities of the T. indica fruit pulp.

  9. Early adaptive response of the retina to a pro-diabetogenic diet: Impairment of cone response and gene expression changes in high-fructose fed rats.

    PubMed

    Thierry, Magalie; Pasquis, Bruno; Buteau, Bénédicte; Fourgeux, Cynthia; Dembele, Doulaye; Leclere, Laurent; Gambert-Nicot, Ségolène; Acar, Niyazi; Bron, Alain M; Creuzot-Garcher, Catherine P; Bretillon, Lionel

    2015-06-01

    The lack of plasticity of neurons to respond to dietary changes, such as high fat and high fructose diets, by modulating gene and protein expression has been associated with functional and behavioral impairments that can have detrimental consequences. The inhibition of high fat-induced rewiring of hypothalamic neurons induced obesity. Feeding rodents with high fructose is a recognized and widely used model to trigger obesity and metabolic syndrome. However the adaptive response of the retina to short term feeding with high fructose is poorly documented. We therefore aimed to characterize both the functional and gene expression changes in the neurosensory retina of Brown Norway rats fed during 3 and 8 days with a 60%-rich fructose diet (n = 16 per diet and per time point). Glucose, insulin, leptin, triacylglycerols, total cholesterol, HDL-cholesterol, LDL-cholesterol and fructosamine were quantified in plasma (n = 8 in each group). Functionality of the inner retina was studied using scotopic single flash electroretinography (n = 8 in each group) and the individual response of rod and cone photoreceptors was determined using 8.02 Hz Flicker electroretinography (n = 8 in each group). Analysis of gene expression in the neurosensory retina was performed by Affymetrix genechips, and confirmed by RT-qPCR (n = 6 in each group). Elevated glycemia (+13%), insulinemia (+83%), and leptinemia (+172%) was observed after 8 days of fructose feeding. The cone photoreceptor response was altered at day 8 in high fructose fed rats (Δ = 0.5 log unit of light stimulus intensity). Affymetrix analysis of gene expression highlighted significant modulation of the pathways of eIF2 signaling and endoplasmic reticulum stress, regulation of eIF4 and p70S6K signaling, as well as mTOR signaling and mitochondrial dysfunction. RT-qPCR analysis confirmed the down regulation of Crystallins, Npy, Nid1 and Optc genes after 3 days of fructose feeding, and up regulation of End2. Meanwhile, a trend

  10. Pathway network inference from gene expression data

    PubMed Central

    2014-01-01

    Background The development of high-throughput omics technologies enabled genome-wide measurements of the activity of cellular elements and provides the analytical resources for the progress of the Systems Biology discipline. Analysis and interpretation of gene expression data has evolved from the gene to the pathway and interaction level, i.e. from the detection of differentially expressed genes, to the establishment of gene interaction networks and the identification of enriched functional categories. Still, the understanding of biological systems requires a further level of analysis that addresses the characterization of the interaction between functional modules. Results We present a novel computational methodology to study the functional interconnections among the molecular elements of a biological system. The PANA approach uses high-throughput genomics measurements and a functional annotation scheme to extract an activity profile from each functional block -or pathway- followed by machine-learning methods to infer the relationships between these functional profiles. The result is a global, interconnected network of pathways that represents the functional cross-talk within the molecular system. We have applied this approach to describe the functional transcriptional connections during the yeast cell cycle and to identify pathways that change their connectivity in a disease condition using an Alzheimer example. Conclusions PANA is a useful tool to deepen in our understanding of the functional interdependences that operate within complex biological systems. We show the approach is algorithmically consistent and the inferred network is well supported by the available functional data. The method allows the dissection of the molecular basis of the functional connections and we describe the different regulatory mechanisms that explain the network's topology obtained for the yeast cell cycle data. PMID:25032889

  11. inSilicoDb: an R/Bioconductor package for accessing human Affymetrix expert-curated datasets from GEO.

    PubMed

    Taminau, Jonatan; Steenhoff, David; Coletta, Alain; Meganck, Stijn; Lazar, Cosmin; de Schaetzen, Virginie; Duque, Robin; Molter, Colin; Bersini, Hugues; Nowé, Ann; Weiss Solís, David Y

    2011-11-15

    Microarray technology has become an integral part of biomedical research and increasing amounts of datasets become available through public repositories. However, re-use of these datasets is severely hindered by unstructured, missing or incorrect biological samples information; as well as the wide variety of preprocessing methods in use. The inSilicoDb R/Bioconductor package is a command-line front-end to the InSilico DB, a web-based database currently containing 86 104 expert-curated human Affymetrix expression profiles compiled from 1937 GEO repository series. The use of this package builds on the Bioconductor project's focus on reproducibility by enabling a clear workflow in which not only analysis, but also the retrieval of verified data is supported.

  12. Microarray gene expression analysis of fixed archival tissue permits molecular classification and identification of potential therapeutic targets in diffuse large B-cell lymphoma.

    PubMed

    Linton, Kim; Howarth, Christopher; Wappett, Mark; Newton, Gillian; Lachel, Cynthia; Iqbal, Javeed; Pepper, Stuart; Byers, Richard; Chan, Wing John; Radford, John

    2012-01-01

    Refractory/relapsed diffuse large B-cell lymphoma (DLBCL) has a poor prognosis. Novel drugs targeting the constitutively activated NF-κB pathway characteristic of ABC-DLBCL are promising, but evaluation depends on accurate activated B cell-like (ABC)/germinal center B cell-like (GCB) molecular classification. This is traditionally performed on gene microarray expression profiles of fresh biopsies, which are not routinely collected, or by immunohistochemistry on formalin-fixed, paraffin-embedded (FFPE) tissue, which lacks reproducibility and classification accuracy. We explored the possibility of using routine archival FFPE tissue for gene microarray applications. We examined Affymetrix HG U133 Plus 2.0 gene expression profiles from paired archival FFPE and fresh-frozen tissues of 40 ABC/GCB-classified DLBCL cases to compare classification accuracy and test the potential for this approach to aid the discovery of therapeutic targets and disease classifiers in DLBCL. Unsupervised hierarchical clustering of unselected present probe sets distinguished ABC/GCB in FFPE with remarkable accuracy, and a Bayesian classifier correctly assigned 32 of 36 cases with >90% probability. Enrichment for NF-κB genes was appropriately seen in ABC-DLBCL FFPE tissues. The top discriminatory genes expressed in FFPE separated cases with high statistical significance and contained novel biology with potential therapeutic insights, warranting further investigation. These results support a growing understanding that archival FFPE tissues can be used in microarray experiments aimed at molecular classification, prognostic biomarker discovery, and molecular exploration of rare diseases.

  13. Effects of weak, low-frequency pulsed electromagnetic fields (BEMER type) on gene expression of human mesenchymal stem cells and chondrocytes: an in vitro study.

    PubMed

    Walther, Markus; Mayer, Florian; Kafka, Wolf; Schütze, Norbert

    2007-01-01

    In vitro effects of electromagnetic fields appear to be related to the type of electromagnetic field applied. Previously, we showed that human osteoblasts display effects of BEMER type electromagnetic field (BTEMF) on gene regulation. Here, we analyze effects of BTEMF on gene expression in human mesenchymal stem cells and chondrocytes. Primary mesenchymal stem cells from bone marrow and the chondrocyte cell line C28I2 were stimulated 5 times at 12-h intervals for 8 min each with BTEMF. RNA from treated and control cells was analyzed for gene expression using the affymetrix chip HG-U133A. A limited number of regulated gene products from both cell types mainly affect cell metabolism and cell matrix structure. There was no increased expression of cancer-related genes. RT-PCR analysis of selected transcripts partly confirmed array data. Results indicate that BTEMF in human mesenchymal stem cells and chondrocytes provide the first indications to understanding therapeutic effects achieved with BTEMF stimulation. PMID:17886005

  14. Regulation of gene expression by hypoxia.

    PubMed

    Kenneth, Niall Steven; Rocha, Sonia

    2008-08-15

    Hypoxia induces profound changes in the cellular gene expression profile. The discovery of a major transcription factor family activated by hypoxia, HIF (hypoxia-inducible factor), and the factors that contribute to HIF regulation have greatly enhanced our knowledge of the molecular aspects of the hypoxic response. However, in addition to HIF, other transcription factors and cellular pathways are activated by exposure to reduced oxygen. In the present review, we summarize the current knowledge of how additional hypoxia-responsive transcription factors integrate with HIF and how other cellular pathways such as chromatin remodelling, translation regulation and microRNA induction, contribute to the co-ordinated cellular response observed following hypoxic stress.

  15. Network Completion for Static Gene Expression Data

    PubMed Central

    Nakajima, Natsu

    2014-01-01

    We tackle the problem of completing and inferring genetic networks under stationary conditions from static data, where network completion is to make the minimum amount of modifications to an initial network so that the completed network is most consistent with the expression data in which addition of edges and deletion of edges are basic modification operations. For this problem, we present a new method for network completion using dynamic programming and least-squares fitting. This method can find an optimal solution in polynomial time if the maximum indegree of the network is bounded by a constant. We evaluate the effectiveness of our method through computational experiments using synthetic data. Furthermore, we demonstrate that our proposed method can distinguish the differences between two types of genetic networks under stationary conditions from lung cancer and normal gene expression data. PMID:24826192

  16. The effect of PrP(Sc) accumulation on inflammatory gene expression within sheep peripheral lymphoid tissue.

    PubMed

    Gossner, Anton G; Hopkins, John

    2015-12-31

    Accumulation of the misfolded prion protein, PrP(Sc) in the central nervous system (CNS) is strongly linked to progressive neurodegenerative disease. For many transmissible spongiform encephalopathies (TSEs), peripheral lymphoid tissue is an important site of PrP(Sc) amplification but without gross immunological consequence. Susceptible VRQ homozygous New Zealand Cheviot sheep were infected with SSBP/1 scrapie by inoculation in the drainage area of the prescapular lymph nodes. The earliest time that PrP(Sc) was consistently detected by immunohistology in these nodes was D50 post infection. This transcriptomic study of lymph node taken before (D10) and after (D50) the detection of PrP(Sc), aimed to identify the genes and physiological pathways affected by disease progression within the nodes as assessed by PrP(Sc) detection. Affymetrix Ovine Gene arrays identified 75 and 80 genes as differentially-expressed at D10 and D50, respectively, in comparison with control sheep inoculated with uninfected brain homogenate. Approximately 70% of these were repressed at each time point. RT-qPCR analysis of seven genes showed statistically significant correlation with the array data, although the results for IL1RN and TGIF were different between the two technologies. The ingenuity pathway analysis (IPA) and general low level of repression of gene expression in lymphoid tissue, including many inflammatory genes, contrasts with the pro-inflammatory and pro-apoptotic events that occur within the CNS at equivalent stages of disease progression as assessed by PrP(Sc) accumulation.

  17. Gene Expression During the Life Cycle of Drosophila melanogaster

    NASA Astrophysics Data System (ADS)

    Arbeitman, Michelle N.; Furlong, Eileen E. M.; Imam, Farhad; Johnson, Eric; Null, Brian H.; Baker, Bruce S.; Krasnow, Mark A.; Scott, Matthew P.; Davis, Ronald W.; White, Kevin P.

    2002-09-01

    Molecular genetic studies of Drosophila melanogaster have led to profound advances in understanding the regulation of development. Here we report gene expression patterns for nearly one-third of all Drosophila genes during a complete time course of development. Mutations that eliminate eye or germline tissue were used to further analyze tissue-specific gene expression programs. These studies define major characteristics of the transcriptional programs that underlie the life cycle, compare development in males and females, and show that large-scale gene expression data collected from whole animals can be used to identify genes expressed in particular tissues and organs or genes involved in specific biological and biochemical processes.

  18. MADS+: discovery of differential splicing events from Affymetrix exon junction array data

    PubMed Central

    Shen, Shihao; Warzecha, Claude C.; Carstens, Russ P.; Xing, Yi

    2010-01-01

    Motivation: The Affymetrix Human Exon Junction Array is a newly designed high-density exon-sensitive microarray for global analysis of alternative splicing. Contrary to the Affymetrix exon 1.0 array, which only contains four probes per exon and no probes for exon–exon junctions, this new junction array averages eight probes per probeset targeting all exons and exon–exon junctions observed in the human mRNA/EST transcripts, representing a significant increase in the probe density for alternative splicing events. Here, we present MADS+, a computational pipeline to detect differential splicing events from the Affymetrix exon junction array data. For each alternative splicing event, MADS+ evaluates the signals of probes targeting competing transcript isoforms to identify exons or splice sites with different levels of transcript inclusion between two sample groups. MADS+ is used routinely in our analysis of Affymetrix exon junction arrays and has a high accuracy in detecting differential splicing events. For example, in a study of the novel epithelial-specific splicing regulator ESRP1, MADS+ detects hundreds of exons whose inclusion levels are dependent on ESRP1, with a RT-PCR validation rate of 88.5% (153 validated out of 173 tested). Availability: MADS+ scripts, documentations and annotation files are available at http://www.medicine.uiowa.edu/Labs/Xing/MADSplus/. Contact: yi-xing@uiowa.edu PMID:19933160

  19. Streptomyces coelicolor as an expression host for heterologous gene clusters.

    PubMed

    Gomez-Escribano, Juan Pablo; Bibb, Mervyn J

    2012-01-01

    The expression of a gene or a set of genes from one organism in a different species is known as "heterologous expression." In actinomycetes, prolific producers of natural products, heterologous gene expression has been used to confirm the clustering of secondary metabolite biosynthetic genes, to analyze natural product biosynthesis, to produce variants of natural products by genetic engineering, and to discover new compounds by screening genomic libraries. Recent advances in DNA sequencing have enabled the rapid and affordable sequencing of actinomycete genomes and revealed a large number of secondary metabolite gene clusters with no known products. Heterologous expression of these cryptic gene clusters combined with comparative metabolic profiling provides an important means to identify potentially novel compounds. In this chapter, the methods and strategies used to heterologously express actinomycete gene clusters, including the techniques used for cloning secondary metabolite gene clusters, the Streptomyces hosts used for their expression, and the techniques employed to analyze their products by metabolic profiling, are described.

  20. Surveying expression level polymorphism and single-feature polymorphism in near-isogenic wheat lines differing for the Yr5 stripe rust resistance locus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA polymorphisms are valuable for several applications including genotyping, molecular mapping and marker-assisted selection. The Affymetrix Wheat GeneChip was used to survey expression level polymorphisms (ELPs) and single-feature polymorphisms (SFPs) between two near-isogenic wheat genotypes (BC...

  1. Surveying expression level polymorphism and single-feature polymorphism in near-isogenic wheat lines differing for the Yr5 stripe rust resistance locus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA polymorphisms are valuable for several applications including genotyping, molecular mapping and marker-assisted selection. The Affymetrix Wheat GeneChip was used to survey expression level polymorphisms (ELPs) and single-feature polymorphisms (SFPs) between two near-isogenic wheat genotypes (BC7...

  2. Repeatability of published microarray gene expression analyses.

    PubMed

    Ioannidis, John P A; Allison, David B; Ball, Catherine A; Coulibaly, Issa; Cui, Xiangqin; Culhane, Aedín C; Falchi, Mario; Furlanello, Cesare; Game, Laurence; Jurman, Giuseppe; Mangion, Jon; Mehta, Tapan; Nitzberg, Michael; Page, Grier P; Petretto, Enrico; van Noort, Vera

    2009-02-01

    Given the complexity of microarray-based gene expression studies, guidelines encourage transparent design and public data availability. Several journals require public data deposition and several public databases exist. However, not all data are publicly available, and even when available, it is unknown whether the published results are reproducible by independent scientists. Here we evaluated the replication of data analyses in 18 articles on microarray-based gene expression profiling published in Nature Genetics in 2005-2006. One table or figure from each article was independently evaluated by two teams of analysts. We reproduced two analyses in principle and six partially or with some discrepancies; ten could not be reproduced. The main reason for failure to reproduce was data unavailability, and discrepancies were mostly due to incomplete data annotation or specification of data processing and analysis. Repeatability of published microarray studies is apparently limited. More strict publication rules enforcing public data availability and explicit description of data processing and analysis should be considered.

  3. Regulation of gene expression by hypoxia.

    PubMed

    Millhorn, D E; Czyzyk-Krzeska, M; Bayliss, D A; Lawson, E E

    1993-12-01

    The present study was undertaken to determine if gene expression for tyrosine hydroxylase (TH), the rate limiting enzyme in the biosynthesis of catecholamines, is regulated in the carotid body, sympathetic ganglia and adrenal medulla by hypoxia. We found that a reduction in oxygen tension from 21% to 10% caused a substantial increase (200% at 1 hour and 500% at 6 hours exposure) in the concentration of TH mRNA in carotid body type I cells but not in either the sympathetic ganglia or adrenal gland. In addition, we found that hypercapnia, another natural stimulus of carotid body activity, failed to enhance TH mRNA in type I cells. Removal of the sensory and sympathetic innervation of the carotid body failed to prevent the induction of TH mRNA by hypoxia in type I cells. Our results show that TH gene expression is regulated by hypoxia in the carotid body but not in other peripheral catecholamine synthesizing tissue and that the regulatory mechanism is intrinsic to type I cells. PMID:7909954

  4. Insulin-glycerolipid mediators and gene expression

    SciTech Connect

    Standaert, M.L.; Pollet, R.J. )

    1988-06-01

    Insulin is an anabolic polypeptide hormone with pleiotrophic effects. During the decades since the initial description by Banting and Best, the acute effects of insulin have been widely studied with particular focus on the mechanism or mechanisms of insulin activation of hexose transport and regulation of metabolic enzyme activity. However, recently there has been a major expansion of investigation to include insulin regulation of gene expression with multiple insulin-sensitive specific mRNAs now reported. In this review, we explore the involvement of insulin-induced changes in plasma membrane glycerolipid metabolism in the transmembrane signaling process required for insulin regulation of mRNA levels. Insulin increase diacylglycerol levels in insulin-responsive cells, and synthetic diacylglycerols or their phorbol ester diacylglycerol analogs, such as 4{beta}, 9{alpha}, 12{beta}, 13{alpha}, 20-pentahydroxytiglia-1,6-dien-3-one 12{beta}-myristate 13-acetate (TPA), mimic insulin regulation of ornithine decarboxylase mRNA, c-fos mRNA, and phosphoenolpyruvate carboxykinase mRNA levels. This suggests that insulin regulation of specific mRNA levels may be mediated by insulin-induced changes in phospholipid metabolism and that diacylglycerol may play a pivotal role in insulin regulation of gene expression.

  5. Gene transfer and expression in plants.

    PubMed

    Lorence, Argelia; Verpoorte, Robert

    2004-01-01

    Until recently, agriculture and plant breeding relied solely on the accumulated experience of generations of farmers and breeders that is, on sexual transfer of genes between plant species. However, recent developments in plant molecular biology and genomics now give us access to knowledge and understanding of plant genomes and the possibility of modifying them. This chapter presents an updated overview of the two most powerful technologies for transferring genetic material (DNA) into plants: Agrobacterium-mediated transformation and microparticle bombardment (biolistics). Some of the topics that are discussed in detail are the main variables controlling the transformation efficiency that can be achieved using each one of these approaches; the advantages and limitations of each methodology; transient versus stable transformation approaches; the potential of some in planta transformation systems; alternatives to developing transgenic plants without selection markers; the availability of diverse genetic tools generated as part of the genome sequencing of different plant species; transgene expression, gene silencing, and their association with regulatory elements; and prospects and ways to possibly overcome some transgene expression difficulties, in particular the use of matrix-attachment regions (MARs).

  6. Coactivators in PPAR-Regulated Gene Expression

    PubMed Central

    Viswakarma, Navin; Jia, Yuzhi; Bai, Liang; Vluggens, Aurore; Borensztajn, Jayme; Xu, Jianming; Reddy, Janardan K.

    2010-01-01

    Peroxisome proliferator-activated receptor (PPAR)α, β (also known as δ), and γ function as sensors for fatty acids and fatty acid derivatives and control important metabolic pathways involved in the maintenance of energy balance. PPARs also regulate other diverse biological processes such as development, differentiation, inflammation, and neoplasia. In the nucleus, PPARs exist as heterodimers with retinoid X receptor-α bound to DNA with corepressor molecules. Upon ligand activation, PPARs undergo conformational changes that facilitate the dissociation of corepressor molecules and invoke a spatiotemporally orchestrated recruitment of transcription cofactors including coactivators and coactivator-associated proteins. While a given nuclear receptor regulates the expression of a prescribed set of target genes, coactivators are likely to influence the functioning of many regulators and thus affect the transcription of many genes. Evidence suggests that some of the coactivators such as PPAR-binding protein (PBP/PPARBP), thyroid hormone receptor-associated protein 220 (TRAP220), and mediator complex subunit 1 (MED1) may exert a broader influence on the functions of several nuclear receptors and their target genes. Investigations into the role of coactivators in the function of PPARs should strengthen our understanding of the complexities of metabolic diseases associated with energy metabolism. PMID:20814439

  7. Posttranscriptional Control of Gene Expression in Yeast

    PubMed Central

    McCarthy, John E. G.

    1998-01-01

    Studies of the budding yeast Saccharomyces cerevisiae have greatly advanced our understanding of the posttranscriptional steps of eukaryotic gene expression. Given the wide range of experimental tools applicable to S. cerevisiae and the recent determination of its complete genomic sequence, many of the key challenges of the posttranscriptional control field can be tackled particularly effectively by using this organism. This article reviews the current knowledge of the cellular components and mechanisms related to translation and mRNA decay, with the emphasis on the molecular basis for rate control and gene regulation. Recent progress in characterizing translation factors and their protein-protein and RNA-protein interactions has been rapid. Against the background of a growing body of structural information, the review discusses the thermodynamic and kinetic principles that govern the translation process. As in prokaryotic systems, translational initiation is a key point of control. Modulation of the activities of translational initiation factors imposes global regulation in the cell, while structural features of particular 5′ untranslated regions, such as upstream open reading frames and effector binding sites, allow for gene-specific regulation. Recent data have revealed many new details of the molecular mechanisms involved while providing insight into the functional overlaps and molecular networking that are apparently a key feature of evolving cellular systems. An overall picture of the mechanisms governing mRNA decay has only very recently begun to develop. The latest work has revealed new information about the mRNA decay pathways, the components of the mRNA degradation machinery, and the way in which these might relate to the translation apparatus. Overall, major challenges still to be addressed include the task of relating principles of posttranscriptional control to cellular compartmentalization and polysome structure and the role of molecular channelling

  8. Predicting cellular growth from gene expression signatures.

    PubMed

    Airoldi, Edoardo M; Huttenhower, Curtis; Gresham, David; Lu, Charles; Caudy, Amy A; Dunham, Maitreya J; Broach, James R; Botstein, David; Troyanskaya, Olga G

    2009-01-01

    Maintaining balanced growth in a changing environment is a fundamental systems-level challenge for cellular physiology, particularly in microorganisms. While the complete set of regulatory and functional pathways supporting growth and cellular proliferation are not yet known, portions of them are well understood. In particular, cellular proliferation is governed by mechanisms that are highly conserved from unicellular to multicellular organisms, and the disruption of these processes in metazoans is a major factor in the development of cancer. In this paper, we develop statistical methodology to identify quantitative aspects of the regulatory mechanisms underlying cellular proliferation in Saccharomyces cerevisiae. We find that the expression levels of a small set of genes can be exploited to predict the instantaneous growth rate of any cellular culture with high accuracy. The predictions obtained in this fashion are robust to changing biological conditions, experimental methods, and technological platforms. The proposed model is also effective in predicting growth rates for the related yeast Saccharomyces bayanus and the highly diverged yeast Schizosaccharomyces pombe, suggesting that the underlying regulatory signature is conserved across a wide range of unicellular evolution. We investigate the biological significance of the gene expression signature that the predictions are based upon from multiple perspectives: by perturbing the regulatory network through the Ras/PKA pathway, observing strong upregulation of growth rate even in the absence of appropriate nutrients, and discovering putative transcription factor binding sites, observing enrichment in growth-correlated genes. More broadly, the proposed methodology enables biological insights about growth at an instantaneous time scale, inaccessible by direct experimental methods. Data and tools enabling others to apply our methods are available at http://function.princeton.edu/growthrate.

  9. Epidermal differentiation complex (locus 1q21) gene expression in head and neck cancer and normal mucosa.

    PubMed

    Tyszkiewicz, Tomasz; Jarzab, Michal; Szymczyk, Cezary; Kowal, Monika; Krajewska, Jolanta; Jaworska, Magdalena; Fraczek, Marcin; Krajewska, Anna; Hadas, Ewa; Swierniak, Michal; Markowski, Jaroslaw; Lange, Dariusz; Poltorak, Stanislaw; Wiench, Malgorzata; Krecicki, Tomasz; Jarzab, Jerzy; Maciejewski, Adam

    2014-01-01

    Epidermal differentiation complex (EDC) comprises a number of genes associated with human skin diseases including psoriasis, atopic dermatitis and hyperkeratosis. These genes have also been linked to numerous cancers, among them skin, gastric, colorectal, lung, ovarian and renal carcinomas. The involvement of EDC components encoding S100 proteins, small proline-rich proteins (SPRRs) and other genes in the tumorigenesis of head and neck squamous cell cancer (HNSCC) has been previously suggested. The aim of the study was to systematically analyze the expression of EDC components on the transcript level in HNSCC. Tissue specimens from 93 patients with HNC of oral cavity and 87 samples from adjacent or distant grossly normal oral mucosawere analyzed. 48 samples (24 tumor and 24 corresponding surrounding tissue) were hybridized to Affymetrix GeneChip Human 1.0 ST Arrays. For validation by quantitative real-time PCR (QPCR) the total RNA from all180 samples collected in the study was analyzed with Real-Time PCR system and fluorescent amplicon specific-probes. Additional set of samples from 14 patients with laryngeal carcinoma previously obtained by HG-U133 Plus 2.0 microarray was also included in the analyses. The expression of analyzed EDC genes was heterogeneous. Two transcripts (S100A1 and S100A4) were significantly down-regulated in oral cancer when compared to normal mucosa (0.69 and 0.36-fold change, respectively), showing an opposite pattern of expression to the remaining S100 genes. Significant up-regulation in tumors was found for S100A11, S100A7, LCE3D, S100A3 and S100A2 genes. The increased expression of S100A7 was subsequently validated by QPCR, confirming significant differences. The remaining EDC genes, including all encoding SPRR molecules, did not show any differences between oral cancer and normal mucosa. The observed differences were also assessed in the independent set of laryngeal cancer samples, confirming the role of S100A3 and LCE3D transcripts in

  10. A Brassica exon array for whole-transcript gene expression profiling.

    PubMed

    Love, Christopher G; Graham, Neil S; O Lochlainn, Seosamh; Bowen, Helen C; May, Sean T; White, Philip J; Broadley, Martin R; Hammond, John P; King, Graham J

    2010-01-01

    Affymetrix GeneChip® arrays are used widely to study transcriptional changes in response to developmental and environmental stimuli. GeneChip® arrays comprise multiple 25-mer oligonucleotide probes per gene and retain certain advantages over direct sequencing. For plants, there are several public GeneChip® arrays whose probes are localised primarily in 3' exons. Plant whole-transcript (WT) GeneChip® arrays are not yet publicly available, although WT resolution is needed to study complex crop genomes such as Brassica, which are typified by segmental duplications containing paralogous genes and/or allopolyploidy. Available sequence data were sampled from the Brassica A and C genomes, and 142,997 gene models identified. The assembled gene models were then used to establish a comprehensive public WT exon array for transcriptomics studies. The Affymetrix GeneChip® Brassica Exon 1.0 ST Array is a 5 µM feature size array, containing 2.4 million 25-base oligonucleotide probes representing 135,201 gene models, with 15 probes per gene distributed among exons. Discrimination of the gene models was based on an E-value cut-off of 1E(-5), with ≤98% sequence identity. The 135 k Brassica Exon Array was validated by quantifying transcriptome differences between leaf and root tissue from a reference Brassica rapa line (R-o-18), and categorisation by Gene Ontologies (GO) based on gene orthology with Arabidopsis thaliana. Technical validation involved comparison of the exon array with a 60-mer array platform using the same starting RNA samples. The 135 k Brassica Exon Array is a robust platform. All data relating to the array design and probe identities are available in the public domain and are curated within the BrassEnsembl genome viewer at http://www.brassica.info/BrassEnsembl/index.html.

  11. Social regulation of cortisol receptor gene expression

    PubMed Central

    Korzan, Wayne J.; Grone, Brian P.; Fernald, Russell D.

    2014-01-01

    In many social species, individuals influence the reproductive capacity of conspecifics. In a well-studied African cichlid fish species, Astatotilapia burtoni, males are either dominant (D) and reproductively competent or non-dominant (ND) and reproductively suppressed as evidenced by reduced gonadotropin releasing hormone (GnRH1) release, regressed gonads, lower levels of androgens and elevated levels of cortisol. Here, we asked whether androgen and cortisol levels might regulate this reproductive suppression. Astatotilapia burtoni has four glucocorticoid receptors (GR1a, GR1b, GR2 and MR), encoded by three genes, and two androgen receptors (ARα and ARβ), encoded by two genes. We previously showed that ARα and ARβ are expressed in GnRH1 neurons in the preoptic area (POA), which regulates reproduction, and that the mRNA levels of these receptors are regulated by social status. Here, we show that GR1, GR2 and MR mRNAs are also expressed in GnRH1 neurons in the POA, revealing potential mechanisms for both androgens and cortisol to influence reproductive capacity. We measured AR, MR and GR mRNA expression levels in a microdissected region of the POA containing GnRH1 neurons, comparing D and ND males. Using quantitative PCR (qPCR), we found D males had higher mRNA levels of ARα, MR, total GR1a and GR2 in the POA compared with ND males. In contrast, ND males had significantly higher levels of GR1b mRNA, a receptor subtype with a reduced transcriptional response to cortisol. Through this novel regulation of receptor type, neurons in the POA of an ND male will be less affected by the higher levels of cortisol typical of low status, suggesting GR receptor type change as a potential adaptive mechanism to mediate high cortisol levels during social suppression. PMID:25013108

  12. Differences in gene and protein expression and the effects of race/ethnicity on breast cancer subtypes

    PubMed Central

    Chavez-MacGregor, Mariana; Liu, Shuying; De Melo-Gagliato, Debora; Chen, Huiqin; Do, Kim-Anh; Pusztai, Lajos; Symmans, W. Fraser; Nair, Lakshmy; Hortobagyi, Gabriel N.; Mills, Gordon B.; Meric-Bernstam, Funda; Gonzalez-Angulo, Ana M.

    2014-01-01

    Background Differences in gene or protein expression patterns between breast cancers according to race/ethnicity and cancer subtype. Methods Transcriptional profiling was performed using Affymetrix HG-U133A platform in 376 patients and reverse phase protein array analysis (RPPA) was done for 177 proteins in 255 patients from a separate cohort. Unsupervised clustering was conducted, as well as supervised comparison by race and tumor subtype. Standard statistical methods, BRB-Array tools and Ingenuity Pathways software packages were used to analyze the data. Results Median age was 50 years in both cohorts. In the RPPA cohort 54.5% of the tumors were HR-positive, 20.7% HER2-positive and 24.71% triple-negative (TNBC). One hundred and forty-seven (57.6%), 47 (18.43%), 46 (18.1%) of the patients were White, Hispanic and Black, respectively. Unsupervised hierarchal clustering of the protein expression data showed no distinct clusters by race (p-values were 0.492, 0.489 and 0.494 for the HR-positive, HER2-positive and TNBC tumors respectively). In the gene expression cohort, 54.2% of the tumors were HR-positive, 16.5% HER2-positive and 29.3% TNBC. Two hundred and sixteen (57.5%), 111 (29.52%), and 32 (8.52%) patients were white, Hispanic and black, respectively. No probe set with an FDR < 0.05 showed an association with race by breast cancer subtype; similar results were obtained using pathway and gene set enrichment analysis methods. Conclusions we did not detect significant variation in RNA or protein expression comparing different race/ethnicity groups of women with breast cancer Impact More research on the complex network of factors that result in outcomes differences among race/ethnicities is needed. PMID:24296856

  13. Screening of differentially expressed genes in the growth plate of broiler chickens with Tibial Dyschondroplasia by microarray analysis

    PubMed Central

    2013-01-01

    Background Tibial dyschondroplasia (TD) is a common skeletal disorder in broiler chickens. It is characterized by the presence of a non-vascularized and unmineralized cartilage in the growth plate. Previous studies have investigated differential expression of genes related to cartilage development during latter stages of TD. The aim of our study was to identify differentially expressed genes (DEGs) in the growth plate of broiler chickens, which were associated with early stage TD. We induced TD using tetramethylthiuram disulfide (thiram) for 1, 2, and 6 days and determined DEGs with chicken Affymetrix GeneChip assays. The identified DEGs were verified by quantitative polymerase chain reaction (qPCR) assays. Results We identified 1630 DEGs, with 82, 1385, and 429 exhibiting at least 2.0-fold changes (P < 0.05) at days 1, 2, and 6, respectively. These DEGs participate in a variety of biological processes, including cytokine production, oxidation reduction, and cell surface receptor linked signal transduction on day 1; lipid biosynthesis, regulation of growth, cell cycle, positive and negative gene regulation, transcription and transcription regulation, and anti-apoptosis on day 2; and regulation of cell proliferation, transcription, dephosphorylation, catabolism, proteolysis, and immune responses on day 6. The identified DEGs were associated with the following pathways: neuroactive ligand-receptor interaction on day 1; synthesis and degradation of ketone bodies, terpenoid backbone biosynthesis, ether lipid metabolism, JAK-STAT, GnRH signaling pathway, ubiquitin mediated proteolysis, TGF-β signaling, focal adhesion, and Wnt signaling on day 2; and arachidonic acid metabolism, mitogen-activated protein kinase (MAPK) signaling, JAK-STAT, insulin signaling, and glycolysis on day 6. We validated seven DEGs by qPCR. Conclusions Our findings demonstrate previously unrecognized changes in gene transcription associated with early stage TD. The DEGs we identified by

  14. Sex-specific patterns and deregulation of endocrine pathways in the gene expression profiles of Bangladeshi adults exposed to arsenic contaminated drinking water.

    PubMed

    Muñoz, Alexandra; Chervona, Yana; Hall, Megan; Kluz, Thomas; Gamble, Mary V; Costa, Max

    2015-05-01

    Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung and bladder cancers, and cardiovascular disease. Recent research indicates that arsenic may be an endocrine disruptor. This study was conducted to evaluate the nature of gene expression changes among males and females exposed to arsenic contaminated water in Bangladesh at high and low doses. Twenty-nine (55% male) Bangladeshi adults with water arsenic exposure ranging from 50 to 1000 μg/L were selected from the Folic Acid Creatinine Trial. RNA was extracted from peripheral blood mononuclear cells for gene expression profiling using Affymetrix 1.0 ST arrays. Differentially expressed genes were assessed between high and low exposure groups for males and females separately and findings were validated using quantitative real-time PCR. There were 534 and 645 differentially expressed genes (p<0.05) in the peripheral blood mononuclear cells of males and females, respectively, when high and low water arsenic exposure groups were compared. Only 43 genes overlapped between the two sexes, with 29 changing in opposite directions. Despite the difference in gene sets both males and females exhibited common biological changes including deregulation of 17β-hydroxysteroid dehydrogenase enzymes, deregulation of genes downstream of Sp1 (specificity protein 1) transcription factor, and prediction of estrogen receptor alpha as a key hub in cardiovascular networks. Arsenic-exposed adults exhibit sex-specific gene expression profiles that implicate involvement of the endocrine system. Due to arsenic's possible role as an endocrine disruptor, exposure thresholds for arsenic may require different parameters for males and females. PMID:25759245

  15. Sex-specific patterns and deregulation of endocrine pathways in the gene expression profiles of Bangladeshi adults exposed to arsenic contaminated drinking water1

    PubMed Central

    Muñoz, Alexandra; Chervona, Yana; Hall, Megan; Kluz, Thomas; Gamble, Mary V.; Costa, Max

    2015-01-01

    Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung and bladder cancers, and cardiovascular disease. Recent research indicates that arsenic may be an endocrine disruptor. This study was conducted to evaluate the nature of gene expression changes among males and females exposed to arsenic contaminated water in Bangladesh at high and low doses. Twenty-nine (55% male) Bangladeshi adults with water arsenic exposure ranging from 50–1000 µg/ L were selected from the Folic Acid Creatinine Trial. RNA was extracted from peripheral blood mononuclear cells for gene expression profiling using Affymetrix 1.0 ST arrays. Differentially expressed genes were assessed between high and low exposure groups for males and females separately and findings were validated using quantitative real-time PCR. There were 534 and 645 differentially expressed genes (p<0.05) in the peripheral blood mononuclear cells of males and females, respectively, when high and low water arsenic exposure groups were compared. Only 43 genes overlapped between the two sexes, with 29 changing in opposite directions. Despite the difference in gene sets both males and females exhibited common biological changes including deregulation of 17β-hydroxysteroid dehydrogenase enzymes, deregulation of genes downstream of Sp1 (specificity protein 1) transcription factor, and prediction of estrogen receptor alpha as a key hub in cardiovascular networks. Arsenic-exposed adults exhibit sex-specific gene expression profiles that implicate involvement of the endocrine system. Due to arsenic’s possible role as an endocrine disruptor, exposure thresholds for arsenic may require different parameters for males and females. PMID:25759245

  16. Sex-specific patterns and deregulation of endocrine pathways in the gene expression profiles of Bangladeshi adults exposed to arsenic contaminated drinking water.

    PubMed

    Muñoz, Alexandra; Chervona, Yana; Hall, Megan; Kluz, Thomas; Gamble, Mary V; Costa, Max

    2015-05-01

    Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung and bladder cancers, and cardiovascular disease. Recent research indicates that arsenic may be an endocrine disruptor. This study was conducted to evaluate the nature of gene expression changes among males and females exposed to arsenic contaminated water in Bangladesh at high and low doses. Twenty-nine (55% male) Bangladeshi adults with water arsenic exposure ranging from 50 to 1000 μg/L were selected from the Folic Acid Creatinine Trial. RNA was extracted from peripheral blood mononuclear cells for gene expression profiling using Affymetrix 1.0 ST arrays. Differentially expressed genes were assessed between high and low exposure groups for males and females separately and findings were validated using quantitative real-time PCR. There were 534 and 645 differentially expressed genes (p<0.05) in the peripheral blood mononuclear cells of males and females, respectively, when high and low water arsenic exposure groups were compared. Only 43 genes overlapped between the two sexes, with 29 changing in opposite directions. Despite the difference in gene sets both males and females exhibited common biological changes including deregulation of 17β-hydroxysteroid dehydrogenase enzymes, deregulation of genes downstream of Sp1 (specificity protein 1) transcription factor, and prediction of estrogen receptor alpha as a key hub in cardiovascular networks. Arsenic-exposed adults exhibit sex-specific gene expression profiles that implicate involvement of the endocrine system. Due to arsenic's possible role as an endocrine disruptor, exposure thresholds for arsenic may require different parameters for males and females.

  17. Gene expression profiling of Ewing sarcoma tumours reveals the prognostic importance of tumour–stromal interactions: a report from the Children's Oncology Group

    PubMed Central

    Volchenboum, Samuel L.; Andrade, Jorge; Huang, Lei; Barkauskas, Donald A.; Krailo, Mark; Womer, Richard B.; Ranft, Andreas; Potratz, Jenny; Dirksen, Uta; Triche, Timothy J.

    2015-01-01

    Abstract Relapse of Ewing sarcoma (ES) can occur months or years after initial remission, and salvage therapy for relapsed disease is usually ineffective. Thus, there is great need to develop biomarkers that can predict which patients are at risk for relapse so that therapy and post‐therapy evaluation can be adjusted accordingly. For this study, we performed whole genome expression profiling on two independent cohorts of clinically annotated ES tumours in an effort to identify and validate prognostic gene signatures. ES specimens were obtained from the Children's Oncology Group and whole genome expression profiling performed using Affymetrix Human Exon 1.0 ST arrays. Lists of differentially expressed genes between survivors and non‐survivors were used to identify prognostic gene signatures. An independent cohort of tumours from the Euro‐Ewing cooperative group was similarly analysed as a validation cohort. Unsupervised clustering of gene expression data failed to segregate tumours based on outcome. Supervised analysis of survivors versus non‐survivors revealed a small number of differentially expressed genes and several statistically significant gene signatures. Gene‐specific enrichment analysis demonstrated that integrin and chemokine genes were associated with survival in tumours where stromal contamination was present. Tumours that did not harbour stromal contamination showed no association of any genes or pathways with clinical outcome. Our results reflect the challenges of performing RNA‐based assays on archived bone tumour specimens. In addition, they reveal a key role for tumour stroma in determining ES prognosis. Future biological and clinical investigations should focus on elucidating the contribution of tumour:micro‐environment interactions on ES progression and response to therapy. PMID:26052443

  18. Sequence determinants of prokaryotic gene expression level under heat stress.

    PubMed

    Xiong, Heng; Yang, Yi; Hu, Xiao-Pan; He, Yi-Ming; Ma, Bin-Guang

    2014-11-01

    Prokaryotic gene expression is environment-dependent and temperature plays an important role in shaping the gene expression profile. Revealing the regulation mechanisms of gene expression pertaining to temperature has attracted tremendous efforts in recent years particularly owning to the yielding of transcriptome and proteome data by high-throughput techniques. However, most of the previous works concentrated on the characterization of the gene expression profile of individual organism and little effort has been made to disclose the commonality among organisms, especially for the gene sequence features. In this report, we collected the transcriptome and proteome data measured under heat stress condition from recently published literature and studied the sequence determinants for the expression level of heat-responsive genes on multiple layers. Our results showed that there indeed exist commonness and consistent patterns of the sequence features among organisms for the differentially expressed genes under heat stress condition. Some features are attributed to the requirement of thermostability while some are dominated by gene function. The revealed sequence determinants of bacterial gene expression level under heat stress complement the knowledge about the regulation factors of prokaryotic gene expression responding to the change of environmental conditions. Furthermore, comparisons to thermophilic adaption have been performed to reveal the similarity and dissimilarity of the sequence determinants for the response to heat stress and for the adaption to high habitat temperature, which elucidates the complex landscape of gene expression related to the same physical factor of temperature.

  19. Gene expression profiling reveals novel regulation by bisphenol-A in estrogen receptor-{alpha}-positive human cells

    SciTech Connect

    Singleton, David W.; Feng, Yuxin; Yang, Jun; Puga, Alvaro; Lee, Adrian V.; Khan, Sohaib A. . E-mail: sohaib.khan@uc.edu

    2006-01-15

    Bisphenol-A (BPA) shows proliferative actions in uterus and mammary glands and may influence the development of male and female reproductive tracts in utero or during early postnatal life. Because of its ability to function as an estrogen receptor (ER) agonist, BPA has the potential to disrupt normal endocrine signaling through regulation of ER target genes. Some genes are regulated by both estradiol (E2) and BPA, but those exclusive to either agent have not been described. Using a yeast strain incorporating a vitellogenin A2 ERE-LacZ reporter gene into the genome, we found that BPA induced expression of the reporter in colonies transformed with the ER{alpha} expression plasmid, illustrating BPA-mediated regulation within a chromatin context. Additionally, a reporter gene transiently transfected into the endometrial cancer (Ishikawa) cell line also showed BPA activity, although at 100-fold less potency than E2. To compare global gene expression in response to BPA and E2, we used a variant of the MCF-7 breast cancer cell line stably expressing HA-tagged ER{alpha}. Cultures were treated for 3 h with an ethanol vehicle, E2 (10{sup -8} M), or BPA (10{sup -6} M), followed by isolation of RNA and microarray analysis with the human U95A probe array (Affymetrix, Santa Clara, CA, USA). More than 300 genes were changed 2-fold or more by either or both agents, with roughly half being up-regulated and half down-regulated. A number of growth- and development-related genes, such as HOXC1 and C6, Wnt5A, Frizzled, TGF{beta}-2, and STAT inhibitor 2, were found to be affected exclusively by BPA. We used quantitative real-time PCR to verify regulation of the HOXC6 gene, which showed decreased expression of approximately 2.5-fold by BPA. These results reveal novel effects by BPA and E2, raising interesting possibilities regarding the role of endocrine disruptors in sexual development.

  20. Global analysis of patterns of gene expression during Drosophila embryogenesis

    PubMed Central

    Tomancak, Pavel; Berman, Benjamin P; Beaton, Amy; Weiszmann, Richard; Kwan, Elaine; Hartenstein, Volker; Celniker, Susan E; Rubin, Gerald M

    2007-01-01

    Background Cell and tissue specific gene expression is a defining feature of embryonic development in multi-cellular organisms. However, the range of gene expression patterns, the extent of the correlation of expression with function, and the classes of genes whose spatial expression are tightly regulated have been unclear due to the lack of an unbiased, genome-wide survey of gene expression patterns. Results We determined and documented embryonic expression patterns for 6,003 (44%) of the 13,659 protein-coding genes identified in the Drosophila melanogaster genome with over 70,000 images and controlled vocabulary annotations. Individual expression patterns are extraordinarily diverse, but by supplementing qualitative in situ hybridization data with quantitative microarray time-course data using a hybrid clustering strategy, we identify groups of genes with similar expression. Of 4,496 genes with detectable expression in the embryo, 2,549 (57%) fall into 10 clusters representing broad expression patterns. The remaining 1,947 (43%) genes fall into 29 clusters representing restricted expression, 20% patterned as early as blastoderm, with the majority restricted to differentiated cell types, such as epithelia, nervous system, or muscle. We investigate the relationship between expression clusters and known molecular and cellular-physiological functions. Conclusion Nearly 60% of the genes with detectable expression exhibit broad patterns reflecting quantitative rather than qualitative differences between tissues. The other 40% show tissue-restricted expression; the expression patterns of over 1,500 of these genes are documented here for the first time. Within each of these categories, we identified clusters of genes associated with particular cellular and developmental functions. PMID:17645804

  1. Melatonin regulation of antioxidant enzyme gene expression.

    PubMed

    Mayo, J C; Sainz, R M; Antoli, I; Herrera, F; Martin, V; Rodriguez, C

    2002-10-01

    Antioxidant enzymes (AOEs) are part of the primary cellular defense against free radicals induced by toxins and/or spontaneously formed in cells. Melatonin (MLT) has received much attention in recent years due to its direct free radical scavenging and antioxidant properties. In the present work we report that MLT, at physiological serum concentrations (1 nM), increases the mRNA of both superoxide dismutases (SODs) and glutathione peroxidase (GPx) in two neuronal cell lines. The MLT effect on both SODs and GPx mRNA was mediated by a de novo synthesized protein. MLT alters mRNA stability for Cu-Zn SOD and GPx. Experiments with a short time treatment (pulse action) of MLT suggest that the regulation of AOE gene expression is likely to be receptor mediated, because 1-h treatment with MLT results in the same response as a 24-h treatment.

  2. Gene expression during fruit ripening in avocado.

    PubMed

    Christoffersen, R E; Warm, E; Laties, G G

    1982-06-01

    The poly(A) (+)RNA populations from avocado fruit (Persea americana Mill cv. Hass) at four stages of ripening were isolated by two cycles of oligo-dT-cellulose chromatography and examined by invitro translation, using the rabbit reticulocyte lysate system, followed by two-dimensional gel electrophoresis (isoelectric focusing followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis) of the resulting translation products. Three mRNAs increased dramatically with the climacteric rise in respiration and ethylene production. The molecular weights of the corresponding translation products from the ripening-related mRNAs are 80,000, 36,000, and 16,500. These results indicate that ripening may be linked to the expression of specific genes.

  3. Monoallelic expression of the human FOXP2 speech gene.

    PubMed

    Adegbola, Abidemi A; Cox, Gerald F; Bradshaw, Elizabeth M; Hafler, David A; Gimelbrant, Alexander; Chess, Andrew

    2015-06-01

    The recent descriptions of widespread random monoallelic expression (RMAE) of genes distributed throughout the autosomal genome indicate that there are more genes subject to RMAE on autosomes than the number of genes on the X chromosome where X-inactivation dictates RMAE of X-linked genes. Several of the autosomal genes that undergo RMAE have independently been implicated in human Mendelian disorders. Thus, parsing the relationship between allele-specific expression of these genes and disease is of interest. Mutations in the human forkhead box P2 gene, FOXP2, cause developmental verbal dyspraxia with profound speech and language deficits. Here, we show that the human FOXP2 gene undergoes RMAE. Studying an individual with developmental verbal dyspraxia, we identify a deletion 3 Mb away from the FOXP2 gene, which impacts FOXP2 gene expression in cis. Together these data suggest the intriguing possibility that RMAE impacts the haploinsufficiency phenotypes observed for FOXP2 mutations.

  4. Optimizing retroviral gene expression for effective therapies.

    PubMed

    Antoniou, Michael N; Skipper, Kristian Alsbjerg; Anakok, Omer

    2013-04-01

    With their ability to integrate their genetic material into the target cell genome, retroviral vectors (RV) of both the gamma-retroviral (γ-RV) and lentiviral vector (LV) classes currently remain the most efficient and thus the system of choice for achieving transgene retention and therefore potentially long-term expression and therapeutic benefit. However, γ-RV and LV integration comes at a cost in that transcription units will be present within a native chromatin environment and thus be subject to epigenetic effects (DNA methylation, histone modifications) that can negatively impact on their function. Indeed, highly variable expression and silencing of γ-RV and LV transgenes especially resulting from promoter DNA methylation is well documented and was the cause of the failure of gene therapy in a clinical trial for X-linked chronic granulomatous disease. This review will critically explore the use of different classes of genetic control elements that can in principle reduce vector insertion site position effects and epigenetic-mediated silencing. These transcriptional regulatory elements broadly divide themselves into either those with a chromatin boundary or border function (scaffold/matrix attachment regions, insulators) or those with a dominant chromatin remodeling and transcriptional activating capability (locus control regions,, ubiquitous chromatin opening elements). All these types of elements have their strengths and weaknesses within the constraints of a γ-RV and LV backbone, showing varying degrees of efficacy in improving reproducibility and stability of transgene function. Combinations of boundary and chromatin remodeling; transcriptional activating elements, which do not impede vector production; transduction efficiency; and stability are most likely to meet the requirements within a gene therapy context especially when targeting a stem cell population.

  5. Phenotypic plasticity and divergence in gene expression.

    PubMed

    Healy, Timothy M; Schulte, Patricia M

    2015-07-01

    The extent to which phenotypic plasticity, or the ability of a single genotype to produce different phenotypes in different environments, impedes or promotes genetic divergence has been a matter of debate within evolutionary biology for many decades (see, for example, Ghalambor et al. ; Pfennig et al. ). Similarly, the role of evolution in shaping phenotypic plasticity remains poorly understood (Pigliucci ). In this issue of Molecular Ecology, Dayan et al. () provide empirical data relevant to these questions by assessing the extent of plasticity and divergence in the expression levels of 2272 genes in muscle tissue from killifish (genus Fundulus) exposed to different temperatures. F. heteroclitus (Fig. A) and F. grandis are minnows that inhabit estuarine marshes (Fig. B) along the coasts of the Atlantic Ocean and Gulf of Mexico in North America. These habitats undergo large variations in temperature both daily and seasonally, and these fish are known to demonstrate substantial phenotypic plasticity in response to temperature change (e.g. Fangue et al. ). Furthermore, the range of F. heteroclitus spans a large latitudinal gradient of temperatures, such that northern populations experience temperatures that are on average ~10°C colder than do southern populations (Schulte ). By comparing gene expression patterns between populations of these fish from different thermal habitats held in the laboratory at three different temperatures, Dayan et al. () address two important questions regarding the interacting effects of plasticity and evolution: (i) How does phenotypic plasticity affect adaptive divergence? and (ii) How does adaptive divergence affect plasticity? PMID:26096949

  6. Modulation of R-gene expression across environments

    PubMed Central

    MacQueen, Alice; Bergelson, Joy

    2016-01-01

    Some environments are more conducive to pathogen growth than others, and, as a consequence, plants might be expected to invest more in resistance when pathogen growth is favored. Resistance (R-) genes in Arabidopsis thaliana have unusually extensive variation in basal expression when comparing the same R-gene among accessions collected from different environments. R-gene expression variation was characterized to explore whether R-gene expression is up-regulated in environments favoring pathogen proliferation and down-regulated when risks of infection are low; down-regulation would follow if costs of R-gene expression negatively impact plant fitness in the absence of disease. Quantitative reverse transcription–PCR was used to quantify the expression of 13 R-gene loci in plants grown in eight environmental conditions for each of 12 A. thaliana accessions, and large effects of the environment on R-gene expression were found. Surprisingly, almost every change in the environment—be it a change in biotic or abiotic conditions—led to an increase in R-gene expression, a response that was distinct from the average transcriptome response and from that of other stress response genes. These changes in expression are functional in that environmental change prior to infection affected levels of specific disease resistance to isolates of Pseudomonas syringae. In addition, there are strong latitudinal clines in basal R-gene expression and clines in R-gene expression plasticity correlated with drought and high temperatures. These results suggest that variation in R-gene expression across environments may be shaped by natural selection to reduce fitness costs of R-gene expression in permissive or predictable environments. PMID:26983577

  7. Modulation of R-gene expression across environments.

    PubMed

    MacQueen, Alice; Bergelson, Joy

    2016-03-01

    Some environments are more conducive to pathogen growth than others, and, as a consequence, plants might be expected to invest more in resistance when pathogen growth is favored. Resistance (R-) genes in Arabidopsis thaliana have unusually extensive variation in basal expression when comparing the same R-gene among accessions collected from different environments. R-gene expression variation was characterized to explore whether R-gene expression is up-regulated in environments favoring pathogen proliferation and down-regulated when risks of infection are low; down-regulation would follow if costs of R-gene expression negatively impact plant fitness in the absence of disease. Quantitative reverse transcription-PCR was used to quantify the expression of 13 R-gene loci in plants grown in eight environmental conditions for each of 12 A. thaliana accessions, and large effects of the environment on R-gene expression were found. Surprisingly, almost every change in the environment--be it a change in biotic or abiotic conditions--led to an increase in R-gene expression, a response that was distinct from the average transcriptome response and from that of other stress response genes. These changes in expression are functional in that environmental change prior to infection affected levels of specific disease resistance to isolates of Pseudomonas syringae. In addition, there are strong latitudinal clines in basal R-gene expression and clines in R-gene expression plasticity correlated with drought and high temperatures. These results suggest that variation in R-gene expression across environments may be shaped by natural selection to reduce fitness costs of R-gene expression in permissive or predictable environments. PMID:26983577

  8. Chronic Lunar Dust Exposure on Rat Cornea: Evaluation by Gene Expression Profiling

    NASA Technical Reports Server (NTRS)

    Theriot, C. A.; Glass, A.; Lam, C-W.; James, J.; Zanello, S. B.

    2014-01-01

    Lunar dust is capable of entering habitats and vehicle compartments by sticking to spacesuits or other objects that are transferred into the spacecraft from the lunar surface and has been reported to cause irritation upon exposure. During the Apollo missions, crewmembers reported irritation specifically to the skin and eyes after contamination of the lunar and service modules. It has since been hypothesized that ocular irritation and abrasion might occur as a result of such exposure, impairing crew vision. Recent work has shown that both ultrafine and unground lunar dust exhibited minimal irritancy of the ocular surface (i.e., cornea); however, the assessment of the severity of ocular damage resulting from contact of lunar dust particles to the cornea has focused only on macroscopic signs of mechanical irritancy and cytotoxicity. Given the chemical reactive properties of lunar dust, exposure of the cornea may contribute to detrimental effects at the molecular level including but not limited to oxidative damage. Additionally, low level chronic exposures may confound any results obtained in previous acute studies. We report here preliminary results from a tissue sharing effort using 10-week-old Fischer 344 male rats chronically exposed to filtered air or jet milled lunar dust collected during Apollo 14 using a Jaeger-NYU nose-only chamber for a total of 120 hours (6 hours daily, 5 days a week) over a 4-week period. RNA was isolated from corneas collected from rats at 1 day and 7 days after being exposed to concentrations of 0, 20, and 60 mg/m3 of lunar dust. Microarray analysis was performed using the Affymetrix GeneChip Rat Genome 230 2.0 Array with Affymetrix Expression Console and Transcriptome Analysis Console used for normalization and secondary analysis. An Ingenuity iReport"TM" was then generated for canonical pathway identification. The number of differentially expressed genes identified increases with dose compared to controls suggesting a more severe

  9. Many body theory of stochastic gene expression

    NASA Astrophysics Data System (ADS)

    Walczak, Aleksandra M.

    The regulation of expression states of genes in cells is a stochastic process. The relatively small numbers of protein molecules of a given type present in the cell and the nonlinear nature of chemical reactions result in behaviours, which are hard to anticipate without an appropriate mathematical development. In this dissertation, I develop theoretical approaches based on methods of statistical physics and many-body theory, in which protein and operator state dynamics are treated stochastically and on an equal footing. This development allows me to study the general principles of how noise arising on different levels of the regulatory system affects the complex collective characteristics of systems observed experimentally. I discuss simple models and approximations, which allow for, at least some, analytical progress in these problems. These have allowed us to understand how the operator state fluctuations may influence the steady state properties and lifetimes of attractors of simple gene systems. I show, that for fast binding and unbinding from the DNA, the operator state may be taken to be in equilibrium for highly cooperative binding, when predicting steady state properties as is traditionally done. Nevertheless, if proteins are produced in bursts, the DNA binding state fluctuations must be taken into account explicitly. Furthermore, even when the steady state probability distributions are weakly influenced by the operator state fluctuations, the escape rate in biologically relevant regimes strongly depends on transcription factor-DNA binding rates.

  10. Expression profiling identifies genes involved in emphysema severity.

    PubMed

    Francis, Santiyagu M Savarimuthu; Larsen, Jill E; Pavey, Sandra J; Bowman, Rayleen V; Hayward, Nicholas K; Fong, Kwun M; Yang, Ian A

    2009-01-01

    Chronic obstructive pulmonary disease (COPD) is a major public health problem. The aim of this study was to identify genes involved in emphysema severity in COPD patients.Gene expression profiling was performed on total RNA extracted from non-tumor lung tissue from 30 smokers with emphysema. Class comparison analysis based on gas transfer measurement was performed to identify differentially expressed genes. Genes were then selected for technical validation by quantitative reverse transcriptase-PCR (qRT-PCR) if also represented on microarray platforms used in previously published emphysema studies. Genes technically validated advanced to tests of biological replication by qRT-PCR using an independent test set of 62 lung samples.Class comparison identified 98 differentially expressed genes (p < 0.01). Fifty-one of those genes had been previously evaluated in differentiation between normal and severe emphysema lung. qRT-PCR confirmed the direction of change in expression in 29 of the 51 genes and 11 of those validated, remaining significant at p < 0.05. Biological replication in an independent cohort confirmed the altered expression of eight genes, with seven genes differentially expressed by greater than 1.3 fold, identifying these as candidate determinants of emphysema severity.Gene expression profiling of lung from emphysema patients identified seven candidate genes associated with emphysema severity including COL6A3, SERPINF1, ZNHIT6, NEDD4, CDKN2A, NRN1 and GSTM3. PMID:19723343

  11. Expression profiling identifies genes involved in emphysema severity

    PubMed Central

    2009-01-01

    Chronic obstructive pulmonary disease (COPD) is a major public health problem. The aim of this study was to identify genes involved in emphysema severity in COPD patients. Gene expression profiling was performed on total RNA extracted from non-tumor lung tissue from 30 smokers with emphysema. Class comparison analysis based on gas transfer measurement was performed to identify differentially expressed genes. Genes were then selected for technical validation by quantitative reverse transcriptase-PCR (qRT-PCR) if also represented on microarray platforms used in previously published emphysema studies. Genes technically validated advanced to tests of biological replication by qRT-PCR using an independent test set of 62 lung samples. Class comparison identified 98 differentially expressed genes (p < 0.01). Fifty-one of those genes had been previously evaluated in differentiation between normal and severe emphysema lung. qRT-PCR confirmed the direction of change in expression in 29 of the 51 genes and 11 of those validated, remaining significant at p < 0.05. Biological replication in an independent cohort confirmed the altered expression of eight genes, with seven genes differentially expressed by greater than 1.3 fold, identifying these as candidate determinants of emphysema severity. Gene expression profiling of lung from emphysema patients identified seven candidate genes associated with emphysema severity including COL6A3, SERPINF1, ZNHIT6, NEDD4, CDKN2A, NRN1 and GSTM3. PMID:19723343

  12. Validation of the Lung Subtyping Panel in Multiple Fresh-Frozen and Formalin-Fixed, Paraffin-Embedded Lung Tumor Gene Expression Data Sets.

    PubMed

    Faruki, Hawazin; Mayhew, Gregory M; Fan, Cheng; Wilkerson, Matthew D; Parker, Scott; Kam-Morgan, Lauren; Eisenberg, Marcia; Horten, Bruce; Hayes, D Neil; Perou, Charles M; Lai-Goldman, Myla

    2016-06-01

    Context .- A histologic classification of lung cancer subtypes is essential in guiding therapeutic management. Objective .- To complement morphology-based classification of lung tumors, a previously developed lung subtyping panel (LSP) of 57 genes was tested using multiple public fresh-frozen gene-expression data sets and a prospectively collected set of formalin-fixed, paraffin-embedded lung tumor samples. Design .- The LSP gene-expression signature was evaluated in multiple lung cancer gene-expression data sets totaling 2177 patients collected from 4 platforms: Illumina RNAseq (San Diego, California), Agilent (Santa Clara, California) and Affymetrix (Santa Clara) microarrays, and quantitative reverse transcription-polymerase chain reaction. Gene centroids were calculated for each of 3 genomic-defined subtypes: adenocarcinoma, squamous cell carcinoma, and neuroendocrine, the latter of which encompassed both small cell carcinoma and carcinoid. Classification by LSP into 3 subtypes was evaluated in both fresh-frozen and formalin-fixed, paraffin-embedded tumor samples, and agreement with the original morphology-based diagnosis was determined. Results .- The LSP-based classifications demonstrated overall agreement with the original clinical diagnosis ranging from 78% (251 of 322) to 91% (492 of 538 and 869 of 951) in the fresh-frozen public data sets and 84% (65 of 77) in the formalin-fixed, paraffin-embedded data set. The LSP performance was independent of tissue-preservation method and gene-expression platform. Secondary, blinded pathology review of formalin-fixed, paraffin-embedded samples demonstrated concordance of 82% (63 of 77) with the original morphology diagnosis. Conclusions .- The LSP gene-expression signature is a reproducible and objective method for classifying lung tumors and demonstrates good concordance with morphology-based classification across multiple data sets. The LSP panel can supplement morphologic assessment of lung cancers, particularly

  13. Stochastic models of gene expression and post-transcriptional regulation

    NASA Astrophysics Data System (ADS)

    Pendar, Hodjat; Kulkarni, Rahul; Jia, Tao

    2011-10-01

    The intrinsic stochasticity of gene expression can give rise to phenotypic heterogeneity in a population of genetically identical cells. Correspondingly, there is considerable interest in understanding how different molecular mechanisms impact the 'noise' in gene expression. Of particular interest are post-transcriptional regulatory mechanisms involving genes called small RNAs, which control important processes such as development and cancer. We propose and analyze general stochastic models of gene expression and derive exact analytical expressions quantifying the noise in protein distributions [1]. Focusing on specific regulatory mechanisms, we analyze a general model for post-transcriptional regulation of stochastic gene expression [2]. The results obtained provide new insights into the role of post-transcriptional regulation in controlling the noise in gene expression. [4pt] [1] T. Jia and R. V. Kulkarni, Phys. Rev. Lett.,106, 058102 (2011) [0pt] [2] T. Jia and R. V. Kulkarni, Phys. Rev. Lett., 105, 018101 (2010)

  14. Structure and expression of the ATFa gene.

    PubMed

    Goetz, J; Chatton, B; Mattei, M G; Kedinger, C

    1996-11-22

    The human ATFa proteins belong to the ATF/CREB family of transcription factors. We have previously shown that they mediate the transcriptional activation by the largest E1a protein and can heterodimerize with members of the Jun/Fos family. ATFa proteins have also been found tightly associated with JNK2, a stress-activated kinase. We now report on the structure of the ATFa gene, which mapped to chromosome 12 (band 12q13). Sequence analysis revealed that ATFa isoforms are generated by alternative splice donor site usage. A minimal promoter region of approximately 200 base pairs was identified that retained nearly full transcriptional activity. Binding sites for potential transcription factors were delineated within a GC-rich segment by DNase I footprinting. Expression studies revealed that ATFa accumulates in the nuclei of transfected cells, and the nuclear localization signal was defined next to the leucine zipper domain. As revealed by hybridization with mouse ATFa sequences, low levels of ATFa mRNAs were ubiquitously distributed in fetal or adult mice, with enhanced expression in particular tissues, like squamous epithelia and specific brain cell layers. The possible significance of coexpression of ATFa, ATF-2, and Jun at similar sites in the brain is discussed. PMID:8939888

  15. Laser capture microdissection for gene expression analysis.

    PubMed

    Bidarimath, Mallikarjun; Edwards, Andrew K; Tayade, Chandrakant

    2015-01-01

    Laser capture microdissection (LCM) is an excellent and perhaps the only platform to isolate homogeneous cell populations from specific microscopic regions of heterogeneous tissue section, under direct microscopic visualization. The basic operations of the LCM system are based on (a) microscopic visualization of phenotypically identified cells of interest, (b) selective adherence of cells to a melting thermolabile film/membrane using a low-energy infrared laser (IR system) or photovolatization of cells within a selected region (UV system), (c) capturing or catapulting of structurally intact cells from a stained tissue section. RNA/DNA or protein can be extracted from the cell or tissue fragments for downstream applications to quantitatively study gene expression. This method can be applied to many downstream analyses including but not limited to quantitative real-time polymerase chain reaction (PCR), microarray, DNA genotyping, RNA transcript profiling, generation of cDNA library, mass spectrometry analysis, and proteomic discovery.The application of LCM is described here to specifically and reliably obtain a homogeneous cell population in order to extract RNA to study microRNA expression by quantitative real-time PCR.

  16. Laser capture microdissection for gene expression analysis.

    PubMed

    Bidarimath, Mallikarjun; Edwards, Andrew K; Tayade, Chandrakant

    2015-01-01

    Laser capture microdissection (LCM) is an excellent and perhaps the only platform to isolate homogeneous cell populations from specific microscopic regions of heterogeneous tissue section, under direct microscopic visualization. The basic operations of the LCM system are based on (a) microscopic visualization of phenotypically identified cells of interest, (b) selective adherence of cells to a melting thermolabile film/membrane using a low-energy infrared laser (IR system) or photovolatization of cells within a selected region (UV system), (c) capturing or catapulting of structurally intact cells from a stained tissue section. RNA/DNA or protein can be extracted from the cell or tissue fragments for downstream applications to quantitatively study gene expression. This method can be applied to many downstream analyses including but not limited to quantitative real-time polymerase chain reaction (PCR), microarray, DNA genotyping, RNA transcript profiling, generation of cDNA library, mass spectrometry analysis, and proteomic discovery.The application of LCM is described here to specifically and reliably obtain a homogeneous cell population in order to extract RNA to study microRNA expression by quantitative real-time PCR. PMID:25308266

  17. Blood cell gene expression associated with cellular stress defense is modulated by antioxidant-rich food in a randomised controlled clinical trial of male smokers

    PubMed Central

    2010-01-01

    Background Plant-based diets rich in fruit and vegetables can prevent development of several chronic age-related diseases. However, the mechanisms behind this protective effect are not elucidated. We have tested the hypothesis that intake of antioxidant-rich foods can affect groups of genes associated with cellular stress defence in human blood cells. Trial registration number: NCT00520819 http://clinicaltrials.gov. Methods In an 8-week dietary intervention study, 102 healthy male smokers were randomised to either a diet rich in various antioxidant-rich foods, a kiwifruit diet (three kiwifruits/d added to the regular diet) or a control group. Blood cell gene expression profiles were obtained from 10 randomly selected individuals of each group. Diet-induced changes on gene expression were compared to controls using a novel application of the gene set enrichment analysis (GSEA) on transcription profiles obtained using Affymetrix HG-U133-Plus 2.0 whole genome arrays. Results Changes were observed in the blood cell gene expression profiles in both intervention groups when compared to the control group. Groups of genes involved in regulation of cellular stress defence, such as DNA repair, apoptosis and hypoxia, were significantly upregulated (GSEA, FDR q-values < 5%) by both diets compared to the control group. Genes with common regulatory motifs for aryl hydrocarbon receptor (AhR) and AhR nuclear translocator (AhR/ARNT) were upregulated by both interventions (FDR q-values < 5%). Plasma antioxidant biomarkers (polyphenols/carotenoids) increased in both groups. Conclusions The observed changes in the blood cell gene expression profiles suggest that the beneficial effects of a plant-based diet on human health may be mediated through optimization of defence processes. PMID:20846424

  18. Gene Expression Profiling in Pachyonychia Congenita Skin

    PubMed Central

    Cao, Yu-An; Hickerson, Robyn P.; Seegmiller, Brandon L.; Grapov, Dmitry; Gross, Maren M.; Bessette, Marc R.; Phinney, Brett S.; Flores, Manuel A.; Speaker, Tycho J.; Vermeulen, Annaleen; Bravo, Albert A.; Bruckner, Anna L.; Milstone, Leonard M.; Schwartz, Mary E.; Rice, Robert H.; Kaspar, Roger L.

    2015-01-01

    Background Pachyonychia congenita (PC) is a skin disorder resulting from mutations in keratin (K) proteins including K6a, K6b, K16, and K17. One of the major symptoms is painful plantar keratoderma. The pathogenic sequelae resulting from the keratin mutations remain unclear. Objective To better understand PC pathogenesis. Methods RNA profiling was performed on biopsies taken from PC-involved and uninvolved plantar skin of seven genotyped PC patients (two K6a, one K6b, three K16, and one K17) as well as from control volunteers. Protein profiling was generated from tape-stripping samples. Results A comparison of PC-involved skin biopsies to adjacent uninvolved plantar skin identified 112 differentially-expressed mRNAs common to patient groups harboring K6 (i.e., both K6a and K6b) and K16 mutations. Among these mRNAs, 25 encode structural proteins including keratins, small proline-rich and late cornified envelope proteins, 20 are related to metabolism and 16 encode proteases, peptidases, and their inhibitors including kallikrein-related peptidases (KLKs), and serine protease inhibitors (SERPINs). mRNAs were also identified to be differentially expressed only in K6 (81) or K16 (141) patient samples. Furthermore, 13 mRNAs were identified that may be involved in pain including nociception and neuropathy. Protein profiling, comparing three K6a plantar tape-stripping samples to non-PC controls, showed changes in the PC corneocytes similar, but not identical, to the mRNA analysis. Conclusion Many differentially-expressed genes identified in PC-involved skin encode components critical for skin barrier homeostasis including keratinocyte proliferation, differentiation, cornification, and desquamation. The profiling data provide a foundation for unraveling the pathogenesis of PC and identifying targets for developing effective PC therapeutics. PMID:25656049

  19. Genetic basis of differential opsin gene expression in cichlid fishes.

    PubMed

    Carleton, K L; Hofmann, C M; Klisz, C; Patel, Z; Chircus, L M; Simenauer, L H; Soodoo, N; Albertson, R C; Ser, J R

    2010-04-01

    Visual sensitivity can be tuned by differential expression of opsin genes. Among African cichlid fishes, seven cone opsin genes are expressed in different combinations to produce diverse visual sensitivities. To determine the genetic architecture controlling these adaptive differences, we analysed genetic crosses between species expressing different complements of opsin genes. Quantitative genetic analyses suggest that expression is controlled by only a few loci with correlations among some genes. Genetic mapping identifies clear evidence of trans-acting factors in two chromosomal regions that contribute to differences in opsin expression as well as one cis-regulatory region. Therefore, both cis and trans regulation are important. The simple genetic architecture suggested by these results may explain why opsin gene expression is evolutionarily labile, and why similar patterns of expression have evolved repeatedly in different lineages.

  20. Carcinogen-induced trans activation of gene expression

    SciTech Connect

    Kleinberger, T.; Flint, Y.B.; Blank, M.; Etkin, S.; Lavi, S.

    1988-03-01

    The authors report a new mechanism of carcinogen action by which the expression of several