Littérature scientifique sur le sujet « Transcriptome comparison »
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Articles de revues sur le sujet "Transcriptome comparison"
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Ochsner, Scott A., Christopher M. Watkins, Apollo McOwiti, Xueping Xu, Yolanda F. Darlington, Michael D. Dehart, Austin J. Cooney, David L. Steffen, Lauren B. Becnel et Neil J. McKenna. « Transcriptomine, a web resource for nuclear receptor signaling transcriptomes ». Physiological Genomics 44, no 17 (1 septembre 2012) : 853–63. http://dx.doi.org/10.1152/physiolgenomics.00033.2012.
Texte intégralRésumé :
The nuclear receptor (NR) superfamily of ligand-regulated transcription factors directs ligand- and tissue-specific transcriptomes in myriad developmental, metabolic, immunological, and reproductive processes. The NR signaling field has generated a wealth of genome-wide expression data points, but due to deficits in their accessibility, annotation, and integration, the full potential of these studies has not yet been realized. We searched public gene expression databases and MEDLINE for global transcriptomic datasets relevant to NRs, their ligands, and coregulators. We carried out extensive, deep reannotation of the datasets using controlled vocabularies for RNA Source and regulating molecule and resolved disparate gene identifiers to official gene symbols to facilitate comparison of fold changes and their significance across multiple datasets. We assembled these data points into a database, Transcriptomine ( http://www.nursa.org/transcriptomine ), that allows for multiple, menu-driven querying strategies of this transcriptomic “superdataset,” including single and multiple genes, Gene Ontology terms, disease terms, and uploaded custom gene lists. Experimental variables such as regulating molecule, RNA Source, as well as fold-change and P value cutoff values can be modified, and full data records can be either browsed or downloaded for downstream analysis. We demonstrate the utility of Transcriptomine as a hypothesis generation and validation tool using in silico and experimental use cases. Our resource empowers users to instantly and routinely mine the collective biology of millions of previously disparate transcriptomic data points. By incorporating future transcriptome-wide datasets in the NR signaling field, we anticipate Transcriptomine developing into a powerful resource for the NR- and other signal transduction research communities.
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Gonzalez-Ibeas, Daniel, Pedro J. Martinez-Garcia, Randi A. Famula, Annette Delfino-Mix, Kristian A. Stevens, Carol A. Loopstra, Charles H. Langley, David B. Neale et Jill L. Wegrzyn. « Assessing the Gene Content of the Megagenome : Sugar Pine (Pinus lambertiana) ». G3 Genes|Genomes|Genetics 6, no 12 (1 décembre 2016) : 3787–802. http://dx.doi.org/10.1534/g3.116.032805.
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Abstract Sugar pine (Pinus lambertiana Douglas) is within the subgenus Strobus with an estimated genome size of 31 Gbp. Transcriptomic resources are of particular interest in conifers due to the challenges presented in their megagenomes for gene identification. In this study, we present the first comprehensive survey of the P. lambertiana transcriptome through deep sequencing of a variety of tissue types to generate more than 2.5 billion short reads. Third generation, long reads generated through PacBio Iso-Seq have been included for the first time in conifers to combat the challenges associated with de novo transcriptome assembly. A technology comparison is provided here to contribute to the otherwise scarce comparisons of second and third generation transcriptome sequencing approaches in plant species. In addition, the transcriptome reference was essential for gene model identification and quality assessment in the parallel project responsible for sequencing and assembly of the entire genome. In this study, the transcriptomic data were also used to address questions surrounding lineage-specific Dicer-like proteins in conifers. These proteins play a role in the control of transposable element proliferation and the related genome expansion in conifers.
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Reznikov, Leah R., David K. Meyerholz, Mahmoud Abou Alaiwa, Shin-Ping Kuan, Yan-Shin J. Liao, Nicholas L. Bormann, Thomas B. Bair, Margaret Price, David A. Stoltz et Michael J. Welsh. « The vagal ganglia transcriptome identifies candidate therapeutics for airway hyperreactivity ». American Journal of Physiology-Lung Cellular and Molecular Physiology 315, no 2 (1 août 2018) : L133—L148. http://dx.doi.org/10.1152/ajplung.00557.2017.
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Mainstay therapeutics are ineffective in some people with asthma, suggesting a need for additional agents. In the current study, we used vagal ganglia transcriptome profiling and connectivity mapping to identify compounds beneficial for alleviating airway hyperreactivity (AHR). As a comparison, we also used previously published transcriptome data from sensitized mouse lungs and human asthmatic endobronchial biopsies. All transcriptomes revealed agents beneficial for mitigating AHR; however, only the vagal ganglia transcriptome identified agents used clinically to treat asthma (flunisolide, isoetarine). We also tested one compound identified by vagal ganglia transcriptome profiling that had not previously been linked to asthma and found that it had bronchodilator effects in both mouse and pig airways. These data suggest that transcriptome profiling of the vagal ganglia might be a novel strategy to identify potential asthma therapeutics.
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Quan, Qing, Lu Zhu, Qi Zheng, Hao Wu, Jing Jing, Qing Chen, Ya Liu et al. « Comparison of the pituitary gland transcriptome in pregnant and non-pregnant goats (Capra hircus) ». Czech Journal of Animal Science 64, No. 10 (14 octobre 2019) : 420–30. http://dx.doi.org/10.17221/141/2019-cjas.
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Pregnancy is strictly regulated by neuronal and hormonal factors with an essential role being played by the pituitary gland. We screened for differentially expressed genes (DEGs) in the pituitary that function in goat gestational development. Pregnant (AWGp) and non-pregnant Anhui white goats (AWGn) were analysed by deep-sequencing technology. A total of 12 774 092 and 13 872 327 clear reads were obtained in the AWGp and AWGn libraries, respectively. A total of 2593 genes were labelled as significantly differentially expressed in AWGp compared to AWGn, including 2158 upregulated genes and 435 downregulated genes. These genes included follicle stimulating hormone beta (FSHB) and luteinizing hormone beta (LHB), which showed an involvement in reproductive regulation and downregulation (AWGp vs AWGn). Quantitative real-time PCR (qPCR) results validated the DEG data. Subsequent gene ontology analysis indicated that a large number of these DEGs function in cellular processes, cell structures, and cell binding. The DEGs were also found by Kyoto Gene and Genomic Encyclopaedia analysis to be significantly enriched in 54 pathways, including the GnRH and TGF-beta signalling pathways that affect cell proliferation and hormone secretion. These data also identify genes that may play a role in pregnancy and reproduction in the goat and thus provide avenues for future research.
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Londin, Eric R., Eleftheria Hatzimichael, Phillipe Loher, Leonard C. Edelstein, Chad Shaw, Kathleen Delgrosso, Paolo M. Fortina, Paul F. Bray, Steven E. McKenzie et Isidore Rigoutsos. « Towards a Reference Human Platelet Transcriptome : Evaluation Of Inter-Individual Correlations and Its Relationship With a Platelet Proteome ». Blood 122, no 21 (15 novembre 2013) : 2297. http://dx.doi.org/10.1182/blood.v122.21.2297.2297.
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Abstract Next generation sequencing of RNA (RNA-seq) is an emerging technology that has so far been used successfully to profile the transcriptomes of several cell types and cell states. For the platelet transcriptome, RNA-seq descriptions exist for only a few subjects. Additionally, there have been no studies of the same individual’s transcriptome using two different technologies. As such, it has been unclear how well platelet transcriptomes correlate among different donors or across different RNA platforms, and what the transcriptomes’ relationship is with the platelet proteome. We generated RNA-seq profiles of the long RNA transcriptomes from the platelets of 10 healthy young males (5 white and 5 black). In addition to RNA-seq, we profiled the platelet messenger RNAs of the same 10 individuals using the Affymetrix GeneChip System. We observed that the abundance of platelet mRNA transcripts was highly correlated across the 10 individuals, a finding that was independent of race and of the employed technology. Additionally, our RNA-seq data showed that these high inter-individual correlations extend beyond mRNAs to several categories of non-coding RNAs. However, there was a notable exception: the category of pseudogenes exhibited a clear difference in expression by race. Comparison of our mRNA signatures with the only publicly available quantitative platelet proteome data showed that most (87.5%) identified platelet proteins had a detectable corresponding mRNA. Interestingly, there was also a high number of mRNAs that were present in the transcriptomes of all 10 individuals but had no representation in the proteome. Spearman correlation of the relative abundances for those platelet genes that were represented by both an mRNA and a protein, revealed an unexpectedly weak correlation between the transcriptome and the proteome. Further analysis of the overlapping and non-overlapping platelet mRNAs and proteins identified groups of genes with very distinct characteristics. Gene Ontology analysis of the respective gene identifiers revealed that the gene groups corresponded to distinct cellular processes, an interesting finding that provides novel insights for platelet biology. The very high inter-individual correlations of the transcriptome signatures across 10 different subjects representing two races together with the results of our analyses indicate that it is feasible to assemble a platelet mRNA-ome that can serve as a reference for future platelet transcriptomic studies of human health and disease. Disclosures: No relevant conflicts of interest to declare.
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Zahavi, Tamar, Gil Stelzer, Lior Strauss, Asher Y. Salmon et Mali Salmon-Divon. « VennBLAST—Whole transcriptome comparison and visualization tool ». Genomics 105, no 3 (mars 2015) : 131–36. http://dx.doi.org/10.1016/j.ygeno.2014.12.004.
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Liu, Dandan, Zhengxi Li et Maolin Hou. « Comparison of Transcriptome Responses between Sogatella furcifera Females That Acquired Southern Rice Black-Streaked Dwarf Virus and Not ». Insects 13, no 2 (9 février 2022) : 182. http://dx.doi.org/10.3390/insects13020182.
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The southern rice black-streaked dwarf virus (SRBSDV) is transmitted horizontally by Sogatella furcifera in a persistent, propagative manner. Exposure of S. furcifera females to SRBSDV-infected rice plants may trigger transcriptomic changes in the insects, the transcriptomes of females that acquired SRBSDV and those that failed to, as well as females fed on healthy rice plants as control, were sequenced and compared. Nine transcriptomic libraries were constructed, from which a total of 53,084 genes were assembled. Among the genes, 1043 and 2932 were differentially expressed genes (DEGs) in S. furcifera females that acquired SRBSDV and that failed to, in comparison with the control, respectively. Functional enrichment analysis showed that DEGs identified in S. furcifera females exposed to SRBSDV are primarily involved in diverse signaling pathways related to primary metabolism and innate immunity. The DEGs in the S. furcifera females that failed to acquire the virus significantly outnumbered that in the insects that acquired the virus, and the virus exposure activated the humoral and cellular immune responses of the vectors, especially the apoptosis. The key gene in apoptosis encoding caspase 1 was upregulated by SRBSDV exposure, especially in S. furcifera females that failed to acquire the virus. Analysis of caspase 1 activity validated that SRBSDV exposure induced caspase 1 accumulation. Surprisingly, the expression of six female-specific genes was also upregulated by SRBSDV exposure, which was confirmed by RT-qPCR analysis. This study provides evidence to explain the differential virus acquisition at the transcriptome level.
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Baranwal, Vinay Kumar, Nisha Negi et Paramjit Khurana. « Comparative transcriptomics of leaves of five mulberry accessions and cataloguing structural and expression variants for future prospects ». PLOS ONE 16, no 7 (14 juillet 2021) : e0252246. http://dx.doi.org/10.1371/journal.pone.0252246.
Texte intégralRésumé :
Bombyx mori, a monophagous insect, prefers leaves of the certain species of Morus more than others. The preference has been attributed to morphological and anatomical features and biochemical compounds. In the present manuscript a comparison has been made among the transcriptome of leaves of the two preferred cultivated varieties and three wild types species. While assembling, high quality transcriptomes of five genotypes were constructed with a total of 100930, 151245, 89724, 181761 and 102908 transcripts from ML, MN, MS, K2 and V1 samples respectively. Further, to compare them, orthologs were identified from these assembled transcriptome. A total of 22462, 23413, 23685, 24371, 18362, 22326, 20058, 18049, 17567 and 20518 clusters of orthologs were found in one to one comparison in KvsN, KvsL, KvsS, KvsV, LvsN, LvsS, LvsV, NvsS, NvsV, and SvsV respectively. 4236 orthologs with algebraic connectivity of 1.0 were then used to compare and to find out differentially expressed transcripts from all the genotypes. A total of 1037 transcripts expressed that include some of the important morphology, anatomy and biochemical pathways regulating transcription factors (AP2/ERFs and C2H2 Zinc fingers) and signalling components were identified to express differentially. Further, these transcriptomes were used find out markers (SSR) and variants and a total of 1101013, 537245, 970877, 310437, 675772, 338400, 581189, 751477, 514999 and 257107 variants including SNP, MNP, Insertions and deletions were found in one to one comparisons. Taken together, our data could be highly useful for mulberry community worldwide as it could be utilized in mulberry breeding programs.
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Sseruwagi, Peter, James Wainaina, Joseph Ndunguru, Robooni Tumuhimbise, Fred Tairo, Jian-Yang Guo, Alice Vrielink et al. « The first transcriptomes from field-collected individual whiteflies (Bemisia tabaci, Hemiptera : Aleyrodidae) ». Gates Open Research 1 (28 décembre 2017) : 16. http://dx.doi.org/10.12688/gatesopenres.12783.1.
Texte intégralRésumé :
Background: Bemisia tabaci species (B. tabaci), or whiteflies, are the world’s most devastating insect pests. They cause billions of dollars (US) of damage each year, and are leaving farmers in the developing world food insecure. Currently, all publically available transcriptome data for B. tabaci are generated from pooled samples, which can lead to high heterozygosity and skewed representation of the genetic diversity. The ability to extract enough RNA from a single whitefly has remained elusive due to their small size and technological limitations. Methods: In this study, we optimised the single whitefly RNA extraction procedure, and sequenced the transcriptome of four individual adult Sub-Saharan Africa (SSA1) B. tabaci. Transcriptome sequencing resulted in 39-42 million raw reads. De novo assembly of trimmed reads yielded between 65,000-162,000 transcripts across B. tabaci transcriptomes. Results: Bayesian phylogenetic analysis of mitochondrion cytochrome I oxidase (mtCOI) grouped the four whiteflies within the SSA1 clade. BLASTn searches on the four transcriptomes identified five endosymbionts; the primary endosymbiont Portiera aleyrodidarum and four secondary endosymbionts: Arsenophonus, Wolbachia, Rickettsia, and Cardinium spp. that were predominant across all four SSA1 B. tabaci samples with prevalence levels between 54.1-75%. Amino acid alignments of the NusG gene of P. aleyrodidarum for the SSA1 B. tabaci transcriptomes of samples WF2 and WF2b revealed an eleven amino acid residue deletion that was absent in samples WF1 and WF2a. Comparison of the protein structure of the NusG protein from P. aleyrodidarum in SSA1 with known NusG structures showed the deletion resulted in a shorter D loop. Conclusions: The use of field-collected specimens means time and money will be saved in future studies using single whitefly transcriptomes in monitoring vector and viral interactions. Our method is applicable to any small organism where RNA quantity has limited transcriptome studies.
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Sseruwagi, Peter, James Wainaina, Joseph Ndunguru, Robooni Tumuhimbise, Fred Tairo, Jian-Yang Guo, Alice Vrielink et al. « The first transcriptomes from field-collected individual whiteflies (Bemisia tabaci, Hemiptera : Aleyrodidae) ». Gates Open Research 1 (13 février 2018) : 16. http://dx.doi.org/10.12688/gatesopenres.12783.2.
Texte intégralRésumé :
Background: Bemisia tabaci species (B. tabaci), or whiteflies, are the world’s most devastating insect pests. They cause billions of dollars (US) of damage each year, and are leaving farmers in the developing world food insecure. Currently, all publically available transcriptome data for B. tabaci are generated from pooled samples, which can lead to high heterozygosity and skewed representation of the genetic diversity. The ability to extract enough RNA from a single whitefly has remained elusive due to their small size and technological limitations. Methods: In this study, we optimised a single whitefly RNA extraction procedure, and sequenced the transcriptome of four individual adult Sub-Saharan Africa 1 (SSA1) B. tabaci. Transcriptome sequencing resulted in 39-42 million raw reads. De novo assembly of trimmed reads yielded between 65,000-162,000 Contigs across B. tabaci transcriptomes. Results: Bayesian phylogenetic analysis of mitochondrion cytochrome I oxidase (mtCOI) grouped the four whiteflies within the SSA1 clade. BLASTn searches on the four transcriptomes identified five endosymbionts; the primary endosymbiont Portiera aleyrodidarum and four secondary endosymbionts: Arsenophonus, Wolbachia, Rickettsia, and Cardinium spp. that were predominant across all four SSA1 B. tabaci samples with prevalence levels of between 54.1 to 75%. Amino acid alignments of the NusG gene of P. aleyrodidarum for the SSA1 B. tabaci transcriptomes of samples WF2 and WF2b revealed an eleven amino acid residue deletion that was absent in samples WF1 and WF2a. Comparison of the protein structure of the NusG protein from P. aleyrodidarum in SSA1 with known NusG structures showed the deletion resulted in a shorter D loop. Conclusions: The use of field-collected specimens means time and money will be saved in future studies using single whitefly transcriptomes in monitoring vector and viral interactions. Our method is applicable to any small organism where RNA quantity has limited transcriptome studies.
Thèses sur le sujet "Transcriptome comparison"
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Lim, Raymond. « Wide-scale comparison of transcriptome data and the role of microRNA in major depression and suicide ». Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/38065.
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The first chapter of this thesis addresses a common problem in genomics experiments: interpreting a resulting "hit list" of interesting genes. We present work on an approach for summarizing and exploring "hit lists" that makes use of the large amount of gene expression data in public repositories such as the Gene Expression Omnibus. We compare the query list with datasets that we have analyzed for differential expression of genes. Studies that have similarities to the given hit list yield additional insights, help contextualize studies, and serve as a basis for future meta-analysis. A conceptually similar problem that we addressed is the classification or clustering of datasets based on patterns of differential expression. Both problems required a method for determining distances between datasets based on rankings of genes. We tested and benchmarked several methods using manually annotated datasets. The method that performed best according to our evaluation process is based on Kendall's Tau top-k distance. We investigated potential sources of confounds, finding that the largest challenge may be posed by the high prevalence of certain gene expression patterns. These highly prevalent patterns tended to dominate search results. Nonetheless, we demonstrated the effectiveness of this approach in a case study. In the second chapter, we investigated the role of microRNAs in the context of major depression and suicide. We profiled microRNA and messenger RNA levels in post-mortem prefrontal cortex and hippocampus brain tissue of depressed suicides, suicides, and controls. In the prefrontal cortex, we found miR-1202 to be down-regulated in suicides versus controls, and LCT (lactase enzyme) was up-regulated in suicides or depressed suicides compared to controls. The former result was independently confirmed using quantitative PCR. While further study is needed, our results have the potential to provide insight into molecular changes in the brains of depressed and suicidal individuals.
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Bourgis, F., Aruna Kilaru, X. Cao, E. Legrand, B. Beauvoit, M. Maucourt, C. Deborde et al. « Comparison of Transcriptome Changes Associated to Oil Accumulation in Oil Palm Mesocarp and in Oil Seeds ». Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/4867.
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Brown, Neil Andrew. « Comparison of the infection biology and transcriptome of wild-type and single gene deletion strains of Fusarium graminearum ». Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/9431.
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Fusarium Ear Blight is a devastating fungal disease of cereals and due to the contamination of the harvested grain with a range of trichothecene mycotoxins presents a risk to human and animal health. The re-emergence of Fusarium graminearum on wheat and maize, the evolution of more aggressive fungal strains and the lack of an effective control strategy, has increased the need for a greater understanding of the disease aetiology. This project aimed to enhance the understanding of the interaction between F. graminearum and wheat (Triticum aestivum), through the utilisation of microscopy and molecular pathogenomics. A detailed investigation of the infection process revealed a prolonged latent period of intercellular infection that preceded host cell death, intracellular colonisation and the onset of disease symptoms. Phenotypic differences in colonisation and mycotoxin gene expression implied that hyphae within the two phases of infection were transcriptionally distinct, while a bioinformatic analysis described the fungal secretome. The two fungal gene-deficient strains assessed, top1 and tri5, were unable to establish symptomless infection or spread throughout the wheat ear, in the presence or absence of mycotoxin production, suggesting the existence of additional virulence factors. Subsequently, a genome wide transcriptome investigation of the two phases of infection, using both Affymetrix and RNA-sequencing technologies, revealed the unique expression profile, and secretome, of the advancing hyphal front of the symptomless infections. This greater understanding of the biphasic interaction will provide a benchmark for comparison with the single gene deficient strains. Finally, a laser capture microdissection procedure was developed to enable future cell-type specific transcriptome experiments. Collectively, I have discovered and developed a model of how F. graminearum establishes symptomless and symptomatic infection. In doing so, this study has enhanced the understanding of this non-biotrophic pathosystem, providing many new lines of investigation, which could greatly improve crop protection strategies.
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Lee, Jiyoung. « Computational Analysis of Gene Expression Regulation from Cross Species Comparison to Single Cell Resolution ». Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/99878.
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Gene expression regulation is dynamic and specific to various factors such as developmental stages, environmental conditions, and stimulation of pathogens. Nowadays, a tremendous amount of transcriptome data sets are available from diverse species. This trend enables us to perform comparative transcriptome analysis that identifies conserved or diverged gene expression responses across species using transcriptome data. The goal of this dissertation is to develop and apply approaches of comparative transcriptomics to transfer knowledge from model species to non-model species with the hope that such an approach can contribute to the improvement of crop yield and human health. First, we presented a comprehensive method to identify cross-species modules between two plant species. We adapted the unsupervised network-based module finding method to identify conserved patterns of co-expression and functional conservation between Arabidopsis, a model species, and soybean, a crop species. Second, we compared drought-responsive genes across Arabidopsis, soybean, rice, corn, and Populus in order to explore the genomic characteristics that are conserved under drought stress across species. We identified hundreds of common gene families and conserved regulatory motifs between monocots and dicots. We also presented a BLS-based clustering method which takes into account evolutionary relationships among species to identify conserved co-expression genes. Last, we analyzed single-cell RNA-seq data from monocytes to attempt to understand regulatory mechanism of innate immune system under low-grade inflammation. We identified novel subpopulations of cells treated with lipopolysaccharide (LPS), that show distinct expression patterns from pro-inflammatory genes. The data revealed that a promising therapeutic reagent, sodium 4-phenylbutyrate, masked the effect of LPS. We inferred the existence of specific cellular transitions under different treatments and prioritized important motifs that modulate the transitions using feature selection by a random forest method. There has been a transition in genomics research from bulk RNA-seq to single-cell RNA-seq, and scRNA-seq has become a widely used approach for transcriptome analysis. With the experience we gained by analyzing scRNA-seq data, we plan to conduct comparative single-cell transcriptome analysis across multiple species.Doctor of Philosophy
All cells in an organism have the same set of genes, but there are different cell types, tissues, organs with different functions as the organism ages or under different conditions. Gene expression regulation is one mechanism that modulates complex, dynamic, and specific changes in tissues or cell types for any living organisms. Understanding gene regulation is of fundamental importance in biology. With the rapid advancement of sequencing technologies, there is a tremendous amount of gene expression data (transcriptome) from individual species in public repositories. However, major studies have been reported from several model species and research on non-model species have relied on comparison results with a few model species. Comparative transcriptome analysis across species will help us to transform knowledge from model species to non-model species and such knowledge transfer can contribute to the improvement of crop yields and human health. The focus of my dissertation is to develop and apply approaches for comparative transcriptome analysis that can help us better understand what makes each species unique or special, and what kinds of common functions across species have been passed down from ancestors (evolutionarily conserved functions). Three research chapters are presented in this dissertation. First, we developed a method to identify groups of genes that are commonly co-expressed in two species. We chose seed development data from soybean with the hope to contribute to crop improvement. Second, we compared gene expression data across five plant species including soybean, rice, and corn to provide new perspectives about crop plants. We chose drought stress to identify conserved functions and regulatory factors across species since drought stress is one of the major stresses that negatively impact agricultural production. We also proposed a method that groups genes with evolutionary relationships from an unlimited number of species. Third, we analyzed single-cell RNA-seq data from mouse monocytes to understand the regulatory mechanism of the innate immune system under low-grade inflammation. We observed how innate immune cells respond to inflammation that could cause no symptoms but persist for a long period of time. Also, we reported an effect of a promising therapeutic reagent (sodium 4-phenylbutyrate) on chronic inflammatory diseases. The third project will be extended to comparative single-cell transcriptome analysis with multiple species.
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Wetterbom, Anna. « Genome and Transcriptome Comparisons between Human and Chimpanzee ». Doctoral thesis, Uppsala universitet, Genomik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-112893.
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The chimpanzee is humankind’s closest living relative and the two species diverged ~6 million years ago. Comparative studies of the human and chimpanzee genomes and transcriptomes are of great interest to understand the molecular mechanisms of speciation and the development of species-specific traits. The aim of this thesis is to characterize differences between the two species with regard to their genome sequences and the resulting transcript profiles. The first two papers focus on indel divergence and in particular, indels causing premature termination codons (PTCs) in 8% of the chimpanzee genes. The density of PTC genes is correlated with both the distance to the telomere and the indel divergence. Many PTC genes have several associated transcripts and since not all are affected by the PTC we propose that PTCs may affect the pattern of expressed isoforms. In the third paper, we investigate the transcriptome divergence in cerebellum, heart and liver, using high-density exon arrays. The results show that gene expression differs more between tissues than between species. Approximately 15% of the genes are differentially expressed between species, and half of the genes show different splicing patterns. We identify 28 cassette exons which are only included in one of the species, often in a tissue-specific manner. In the fourth paper, we use massive parallel sequencing to study the chimpanzee transcriptome in frontal cortex and liver. We estimate gene expression and search for novel transcribed regions (TRs). The majority of TRs are located close to genes and possibly extend the annotations. A subset of TRs are not found in the human genome. The brain transcriptome differs substantially from that of the liver and we identify a subset of genes enriched with TRs in frontal cortex. In conclusion, this thesis provides evidence of extensive genomic and transcriptomic variability between human and chimpanzee. The findings provide a basis for further studies of the underlying differences affecting phenotypic divergence between human and chimpanzee.
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Cho, Won Kyong. « Cluster analysis and comparison of various chloroplast and nuclear transcriptomes in Arabidopsis thaliana ». Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-102533.
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Carter, Kristina Kim. « A Comparison of Centrifugal Forces to Reduce the Inhibitory Effects of Food Matrixes on Reverse Transcriptase Polymerase Chain Reaction for the Detection of Food Borne Viruses ». Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/984.
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The CDC estimated that foodborne infections resulted in approximately 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths per year in the United States (Mead, 1999). There are over 200 known diseases caused by viruses, bacteria, parasites, toxins, metals, or prions that can be transmitted through food. Of these illnesses caused by foodborne disease, the CDC estimates that 38.6 million cases are from identifiable pathogens and 30.9 million of these cases are caused by viruses. Hence, approximately 80% of foodborne illnesses of known etiology result from viral transmission (Mead, 1999). Viral gastrointestinal illness may be caused by virus families such as: enterovirus, rotavirus, calicivirus, astrovirus, or norovirus. These viruses are highly contagious and are spread through the fecal-oral route; transmission vehicles include contaminated food or beverages, infected food handlers, fomites or close contact with an infected individual (FDA Bad Bug Book, 2003).
Until recently, there have been few studies concentrating on viruses found in or on foods. There are several technical difficulties that hinder progress in detecting viral agents from foods. One of these problems is the presence of matrix inhibitors. Substances responsible for matrix inhibition include humic acid, polysaccharides, myoglobins, metal ions, glycogen, and lipids (Monpoeho, 2001). These substances in foods produce smearing of the RT-PCR amplicon bands on agarose gels. Several methods to reduce inhibitory compounds utilize multiple toxic reagents in the procedure. In this study, varying centrifugal forces were tested at different steps of the virus extraction/concentration procedure to reduce matrix inhibitory effects for molecular detection of norovirus and poliovirus seeded onto food surfaces. This method incorporates the rapid detection capabilities of RT-PCR with the ability to reduce or eliminate matrix inhibitors present in food, by altering the centrifugal force.
Results for both viruses showed that band intensity decreased as the viral concentration decreased and no one method was superior for all food matrices. This investigation showed that matrix specific modifications to the basic protocol are required to efficiently extract viruses from the surface of foods. Each food should be assessed to determine modifications to the standard method that would be optimal for viral concentration and extraction.
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Adler, Marcel [Verfasser], Günter [Gutachter] Theißen, Klaus [Gutachter] Wimmers et Gerald [Gutachter] Reiner. « Transcriptomic response of porcine PBMCs to experimental tetanus vaccination : comparison of divergent phenotypes for lean growth and antibody titers / Marcel Adler ; Gutachter : Günter Theißen, Klaus Wimmers, Gerald Reiner ». Jena : Friedrich-Schiller-Universität Jena, 2017. http://d-nb.info/1177601451/34.
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Massonnet, Melanie. « Berry transcriptome comparison of ten Italian grapevine varieties ». Doctoral thesis, 2015. http://hdl.handle.net/11562/911799.
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Lo sviluppo della bacca di vite può essere descritto come una successione di cambiamenti fisiologici e biochimici che riflettono la modulazione trascrizionale di molti geni. Nello scorso decennio molti studi trascrittomici sono stati eseguiti per descrivere in modo più approfondito questo processo di sviluppo dinamico e complesso. Tuttavia, la maggior parte di questi studi trascrittomici si sono focalizzati solo su un’unica varietà per volta e quindi vi è ancora una mancanza di risorse per poter effettuare comparazioni sullo sviluppo della bacca in differenti varietà di vite.
Questa tesi riguarda la prima comparazione del trascrittoma della bacca di vite effettuato attraverso RNA sequencing di 120 campioni di RNA, corrispondenti alle bacche di dieci varietà raccolte a quattro stadi fenologici, due precedenti e due successivi all’invaiatura, in triplicato biologico.
Quest’analisi RNA-seq ha mostrato un’evidente e profonda transizione del trascrittoma dalla fase verde alla maturazione che avviene all’invaiatura indipendentemente da colore della buccia e varietà, che coinvolge la soppressione di diversi processi metabolici relativi alla crescita vegetativa, e l’induzione di solo poche vie, come processi di metabolismo secondario e di risposta a stimoli biotici. Questo importante riprogramma del trascrittoma durante la maturazione è stato evidenziato da diversi approcci: correlazione con distanza di Pearson, analisi a componenti principali (PCA), O2PLS-DA, ricerca di biomarcatori, analisi clustering e network di correlazione. La creazione della prima via trascrittomica di sviluppo della bacca di vite, corrispondente a geni aventi un profilo di espressione simile durante tutto lo sviluppo indipendentemente dalla varietà, ha permesso di identificare geni coinvolti nei maggiori processi biologici che avvengono durante la maturazione del frutto. Infine, l’espressione dei geni appartenenti alla via biosintetica dei fenilpropanoidi/flavonoidi si sono mostrati insufficienti da soli nello spiegare le differenze trascrittomiche tra varietà rosse e bianche; tuttavia si presuppone che questi – probabilmente per effetto dell’accumulo di antociani nella buccia della bacca dall’inizio della maturazione – influenzino comunque il programma della fase di maturazione, determinando il coinvolgimento e reclutamento di geni appartenenti ad altri processi biologici.Grape berry development can be described as a succession of physiological and biochemical changes reflecting the transcriptional modulation of many genes. In the last decade, many transcriptomic studies have been carried out to deeper describe this dynamic and complex development. Nonetheless, most of those transcriptomic studies focused on one single variety at a time and then there is still a lack of resources for comparing berry development in different grape varieties. This thesis describes the first berry transcriptome comparison carried out by RNA sequencing of 120 RNA samples, corresponding to 10-variety berries collected at four phenological growth stages, two pre- and two post-véraison, in biological triplication. This RNA-Seq analysis showed an evident deep green-to-maturation transcriptome shift occurring at véraison independently on skin colour and variety, which involves the suppression of diverse metabolic processes related to vegetative growth, and the induction of only a few pathways, such as secondary metabolic processes and responses to biotic stimuli. This fundamental transcriptome reprogramming during ripening was highlighted by distinct approaches: Pearson’s correlation distance, PCA, O2PLS-DA, biomarker discovery, clustering analysis and correlation network method. The establishment of the first grape berry development transcriptomic route, corresponding to the genes having similar patterns of expression during whole development independently on the variety, allowed identifying genes involved in the main biological processes occurring during berry development. Finally, the expression of phenylpropanoid/flavonoid biosynthetic pathway-related genes was found to be insufficient by itself to explain the differences between red- and white-grape transcriptomes, however it was supposed to influence – supposedly by the effect of anthocyanins accumulation in berry skin since the onset of ripening – maturation-phase transcriptional program, determining the recruitment of genes belonging to other biological processes.
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Sai, Na. « Transcriptome comparison of Shiraz (Vitis vinifera) grapevines in distinct sub-regions of the Barossa Valley ». Thesis, 2016. http://hdl.handle.net/2440/112720.
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Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library.Studying the interaction between grapevines and the environment may provide insights of how terroir drives unique characters in wine. Analysing changes in gene expression between different environmental conditions provides a first step in understanding genes that may play a role in grapevine adaption. We, therefore, carried out RNA-seq analysis on Shiraz grapevine leaf tissue harvested from two sub-regions of the Barossa Valley to investigate whether gene expression changes occurred in response to two important environmental factors for plant growth, temperature and elevation. Young leaves from three vineyards in the Barossa central ground and three in the Eden Valley were sampled at budburst. The transcriptome profiling of all samples was clustered by vineyard and separated by region. In total, 429 genes showed significant changes in gene expression between two regions (FDR < 0.001). Among the differentially expressed genes, we found a subset of genes enriched in Gene Ontology (GO) terms that are related to environmental response, including abiotic stress and external biotic stress (Q-value < 0.05). Our study provides preliminary analysis of transcriptome changes in different sub-regions of Barossa Valley and identified potential candidate genes involved in adaptive responses under different environmental condition.
Thesis (M.Bio.(PB)) -- University of Adelaide, Masters of Biotechnology (Plant Biotechnology), School of Agriculture, Food and Wine, 2016
Livres sur le sujet "Transcriptome comparison"
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Davies, Paul. Comparison of the reverse transcriptase-polymerase chain reaction,southern blotting and polymerase chain reaction-enzymelinked immunosorbent assay as techniques for rabies diagnosis. 1995.
Trouver le texte intégralChapitres de livres sur le sujet "Transcriptome comparison"
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Thomson, J. M., P. Stothard et J. P. McNamara. « Transcriptome profile comparison between beef and dairy adipose pooled mRNA reveals differences ». Dans Energy and protein metabolism and nutrition in sustainable animal production, 469–70. Wageningen : Wageningen Academic Publishers, 2013. http://dx.doi.org/10.3920/978-90-8686-781-3_176.
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Croce, Olivier, et Eric Röttinger. « Creating a User-Friendly and Open-Access Gene Expression Database for Comparing Embryonic Development and Regeneration in Nematostella vectensis ». Dans Methods in Molecular Biology, 649–62. New York, NY : Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2172-1_35.
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AbstractThe sea anemone Nematostella vectensis has emerged as a powerful research model to understand at the gene regulatory network level, to what extend regeneration recapitulates embryonic development. Such comparison involves massive transcriptomic analysis, a routine approach for identifying differential gene expression. Here we present a workflow to build a user-friendly, mineable, and open-access database providing access to the scientific community to various RNAseq datasets.
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Yan, Dawei, Kiyoshi Tatematsu, Kazumi Nakabayashi, Akira Endo, Masanori Okamoto et Eiji Nambara. « A Comparison of Transcriptomes Between Germinating Seeds and Growing Axillary Buds of Arabidopsis ». Dans Advances in Plant Dormancy, 223–33. Cham : Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-14451-1_13.
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Huang, Xing, Bo Wang, Jingen Xi, Yajie Zhang, Chunping He, Jinlong Zheng, Jianming Gao et al. « Transcriptome Comparison Reveals Distinct Selection Patterns in Domesticated and Wild Agave Species, the Important CAM Plants ». Dans Top 10 Contributions on Genetics, 02–28. Avid Science, 2019. http://dx.doi.org/10.29290/tcgen.3.1.2019.2-28.
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Cephe, Ahu, Necla Koçhan, Gözde Ertürk Zararsız, Vahap Eldem et Gökmen Zararsız. « Class Discovery, Comparison, and Prediction Methods for RNA-Seq Data ». Dans Encyclopedia of Data Science and Machine Learning, 2060–84. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-9220-5.ch123.
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Gene-expression studies have been studied using microarray data for many years, and numerous methods have been developed for these data. However, microarray technology is old technology and has some limitations. RNA-sequencing (RNA-seq) is a new transcriptomics technique capable of coping with these limitations, using the capabilities of new generation sequencing technologies, and performing operations quickly and cheaply based on the principle of high-throughput sequencing technology. Compared to microarrays, RNA-seq offers several advantages: (1) having less noisy data, (2) being able to detect new transcripts and coding regions, (3) not requiring pre-determination of the transcriptomes of interest. However, RNA-seq data has several features that pose statistical challenges. Thus, one cannot directly use methods developed for microarray analyses, which has a discrete and overdispersed nature of data, quite different from the continuous data structure of microarrays. This article aims to provide an overview and practical guidance to researchers working with RNA-seq data for different purposes.
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Brock, Clifton O., Julie E. Park, Paul A. Volden, Sonal Kashyap et Suzanne D. Conzen. « Comparison of the Glucocorticoid and Mineralcorticoid Receptor Transcriptomes in Primary Human Adipose Tissue ». Dans BASIC/TRANSLATIONAL - Actions of Adrenal Steroid Receptors & ; Other Nuclear Receptors, P3–11—P3–11. The Endocrine Society, 2011. http://dx.doi.org/10.1210/endo-meetings.2011.part3.p16.p3-11.
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Unissa, Ameeruddin Nusrath, et Luke Elizabeth Hanna. « Computational Analysis of Reverse Transcriptase Resistance to Inhibitors in HIV-1 ». Dans Big Data Analytics in HIV/AIDS Research, 1–20. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3203-3.ch001.
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Reverse transcriptase (RT) is a vital enzyme in the process of transcription of HIV-1. The nucleoside analogues of RT inhibitors (NRTIs) act by substrate competition and chain termination as they resemble a nucleotide. To understand the basis of RT resistance in HIV-1, in this chapter, one of the clinically essential mutants Q151M of RT which exhibits multi-resistance to many NRTIs was modeled and docked with NRTIs in comparison to wild type (WT). The results of docking indicate that the WT showed high affinity with all inhibitors compared to the mutant (MT). It can be suggested that the high affinity in WT could be attributed to the favorable interactions with all inhibitors that lacks in MT due to amino acid substitution that leads to structural changes in MT protein, which alters the favorable network of interaction and eventually imparts resistance to all inhibitors.
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Pavlopoulos, Anastasios, et Carsten Wolff. « Crustacean Limb Morphogenesis during Normal Development and Regeneration ». Dans Developmental Biology and Larval Ecology, 46–79. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190648954.003.0002.
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Crustaceans have been favored in developmental biology for the study of the diversification of body plans and their associated appendages, which exhibit remarkable diversity within and between species. Until recently, because of technical limitations, crustacean studies were restricted in scope to the comparison of appendage morphologies and expression patterns of candidate limb patterning genes already known from classic developmental animal models. To remedy this limitation and explore their full potential, a few select crustacean experimental models have been reinforced with powerful genomic and transcriptomic resources, new methods for forward and reverse genetic investigations, and for live imaging of entire embryos, or cell and tissue-specific markers, with exceptional spatial and temporal resolution. These models include the malacostracan amphipod Parhyale hawaiensis and the branchiopod cladocerans Daphnia magna and Daphnia pulex, which display collectively all the different uniramous, biramous, and phyllopodous crustacean limb types. Within the past couple years, important discoveries have been made on the molecular and cellular basis of embryonic limb development and postembryonic limb regeneration. In Parhyale alone, gain and loss-of-function studies of Hox genes have revealed the combinatorial logic used by these genes for appendage specialization, whereas the reconstruction of single-cell-resolution fate maps of developing and regenerating appendages have identified the lineage restrictions and cellular behaviors driving both morphogenetic processes. Century-old questions regarding the conservation and divergence of appendage patterning mechanisms across arthropods and bilaterians, or how these mechanisms can be used and reused throughout the lifetime of an organism, can now be addressed productively with crustaceans.
Actes de conférences sur le sujet "Transcriptome comparison"
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Behera, Sairam, Adam Voshall, Jitender S. Deogun et Etsuko N. Moriyama. « Performance comparison and an ensemble approach of transcriptome assembly ». Dans 2017 IEEE International Conference on Bioinformatics and Biomedicine (BIBM). IEEE, 2017. http://dx.doi.org/10.1109/bibm.2017.8218005.
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jiang, xiaoqian, henry li et sheng guo. « Abstract C118 : Transcriptome comparison of orthotopic and subcutaneous patient-derived xenografts ». Dans Abstracts : AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics ; October 26-30, 2019 ; Boston, MA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1535-7163.targ-19-c118.
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Bell, Achim H., Franco Demonte, Shaan M. Raza, Gregory N. Fuller et Diana Bell. « Abstract A03 : Transcriptome comparison of chordoma of the skull base and spine ». Dans Abstracts : Advances in Sarcomas : From Basic Science to Clinical Translation ; May 16-19, 2017 ; Philadelphia, PA. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1557-3265.sarcomas17-a03.
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« Comparison of brain transcriptome profiles of short-lived and long-lived species of Nothobranchius ». Dans Bioinformatics of Genome Regulation and Structure/ Systems Biology. institute of cytology and genetics siberian branch of the russian academy of science, Novosibirsk State University, 2020. http://dx.doi.org/10.18699/bgrs/sb-2020-015.
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Ferrari, Renata, Guillaume Noell, Laura Caram, Suzana Tanni, Ludimila Nogueira, Simone Vale, Erica Hasimoto et al. « Analysis and comparison of the transcriptome of COPD patients with and without lung cancer ». Dans ERS International Congress 2018 abstracts. European Respiratory Society, 2018. http://dx.doi.org/10.1183/13993003.congress-2018.pa581.
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Song, Seulki, Hyejoo Park, Daeyoon Kim, Sheehyun Kim, Hongseok Yun, Sungyoung Lee, Youngil Koh et Sung-Soo Yoon. « Abstract 145 : Comparison of whole transcriptome sequencing immune repertoire sequencing using RNA for tumor milieu analysis ». Dans Proceedings : AACR Annual Meeting 2019 ; March 29-April 3, 2019 ; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.sabcs18-145.
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Song, Seulki, Hyejoo Park, Daeyoon Kim, Sheehyun Kim, Hongseok Yun, Sungyoung Lee, Youngil Koh et Sung-Soo Yoon. « Abstract 145 : Comparison of whole transcriptome sequencing immune repertoire sequencing using RNA for tumor milieu analysis ». Dans Proceedings : AACR Annual Meeting 2019 ; March 29-April 3, 2019 ; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.am2019-145.
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Salit, Jacqueline, David T. Dang, Matt Teater, Neil R. Hackett et Ronald G. Crystal. « Human Small Airway Transcriptome : Comparison Of Multiple Microarray Platforms To The Sequence Of The Entire Transcriptome To Assess Effect Of Smoking On Human Small Airway Epithelium Gene Expression ». Dans American Thoracic Society 2010 International Conference, May 14-19, 2010 • New Orleans. American Thoracic Society, 2010. http://dx.doi.org/10.1164/ajrccm-conference.2010.181.1_meetingabstracts.a6403.
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Arens, Anne, Anne-Mette K. Hein, Uwe Appelt, Anika Joecker, Søren Mønsted, Bjarne Knudsen, Naomi Thomson, Richard Lussier, Cecilie Boysen et Roald Forsberg. « Abstract 5332 : Comparison of variant calling from whole exome and transcriptome sequencing using CLC Cancer Research Workbench ». Dans Proceedings : AACR Annual Meeting 2014 ; April 5-9, 2014 ; San Diego, CA. American Association for Cancer Research, 2014. http://dx.doi.org/10.1158/1538-7445.am2014-5332.
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Rodenburg, L., S. Michel, K. De Winter-De Groot, C. Van Der Ent, J. Beekman et G. Amatngalim. « Transcriptome comparison between air-liquid interface differentiated nasal and bronchial epithelial cells of infants with cystic fibrosis ». Dans ERS International Congress 2022 abstracts. European Respiratory Society, 2022. http://dx.doi.org/10.1183/13993003.congress-2022.3420.
Texte intégralRapports d'organisations sur le sujet "Transcriptome comparison"
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Katzir, Nurit, James Giovannoni, Marla Binzel, Efraim Lewinsohn, Joseph Burger et Arthur Schaffer. Genomic Approach to the Improvement of Fruit Quality in Melon (Cucumis melo) and Related Cucurbit Crops II : Functional Genomics. United States Department of Agriculture, janvier 2010. http://dx.doi.org/10.32747/2010.7592123.bard.
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Background: Genomics tools for enhancement of melon research, with an emphasis on fruit, were developed through a previous BARD project of the PIs (IS -333-02). These included the first public melon EST collection, a database to relay this information to the research community and a publicly available microarray. The current project (IS-3877- 06) aimed to apply these tools for identification of important genes for improvement of melon (Cucumis melo) fruit quality. Specifically, the research plans included expression analysis using the microarray and functional analyses of selected genes. The original project objectives, as they appeared in the approved project, were: Objective 1: Utilization of a public melon microarray developed under the existing project to characterize melon transcriptome activity during the ripening of normal melon fruit (cv. Galia) in order to provide a basis for both a general view of melon transcriptome activity during ripening and for comparison with existing transcriptome data of developing tomato and pepper fruit. Objective 2: Utilization of the same public melon microarray to characterize melon transcriptome activity in lines available in the collection of the Israeli group, focusing on sugar, organic acids and aroma metabolism, so as to identify potentially useful candidates for functional analysis and possible manipulation, through comparison with the general fruit development profile resulting from (1) above. Objective 3: Expansion of our existing melon EST database to include publicly available gene expression data and query tools, as the US group has done with tomato. Objective 4: Selection of 6-8 candidate genes for functional analysis and development of DNA constructs for repression or over-expression. Objective 5: Creation of transgenic melon lines, or transgenic heterologous systems (e.g. E. coli or tomato), to assess putative functions and potential as tools for molecular enhancement of melon fruit quality, using the candidate gene constructs from (4).
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Miller, Gad, et Jeffrey F. Harper. Pollen fertility and the role of ROS and Ca signaling in heat stress tolerance. United States Department of Agriculture, janvier 2013. http://dx.doi.org/10.32747/2013.7598150.bard.
Texte intégralRésumé :
The long-term goal of this research is to understand how pollen cope with stress, and identify genes that can be manipulated in crop plants to improve reproductive success during heat stress. The specific aims were to: 1) Compare heat stress dependent changes in gene expression between wild type pollen, and mutants in which pollen are heat sensitive (cngc16) or heat tolerant (apx2-1). 2) Compare cngc16 and apx2 mutants for differences in heat-stress triggered changes in ROS, cNMP, and Ca²⁺ transients. 3) Expand a mutant screen for pollen with increased or decreased thermo-tolerance. These aims were designed to provide novel and fundamental advances to our understanding of stress tolerance in pollen reproductive development, and enable research aimed at improving crop plants to be more productive under conditions of heat stress. Background: Each year crop yields are severely impacted by a variety of stress conditions, including heat, cold, drought, hypoxia, and salt. Reproductive development in flowering plants is highly sensitive to hot or cold temperatures, with even a single hot day or cold night sometimes being fatal to reproductive success. In many plants, pollen tube development and fertilization is often the weakest link. Current speculation about global climate change is that most agricultural regions will experience more extreme environmental fluctuations. With the human food supply largely dependent on seeds, it is critical that we consider ways to improve stress tolerance during fertilization. The heat stress response (HSR) has been intensively studied in vegetative tissues, but is poorly understood during reproductive development. A general paradigm is that HS is accompanied by increased production of reactive oxygen species (ROS) and induction of ROS-scavenging enzymes to protect cells from excess oxidative damage. The activation of the HSR has been linked to cytosolic Ca²⁺ signals, and transcriptional and translational responses, including the increased expression of heat shock proteins (HSPs) and antioxidative pathways. The focus of the proposed research was on two mutations, which have been discovered in a collaboration between the Harper and Miller labs, that either increase or decrease reproductive stress tolerance in a model plant, Arabidopsis thaliana (i.e., cngc16--cyclic nucleotide gated channel 16, apx2-1--ascorbate peroxidase 2,). Major conclusions, solutions, achievements. Using RNA-seq technology, the expression profiles of cngc16 and apx2 pollen grains were independently compared to wild type under favourable conditions and following HS. In comparison to a wild type HSR, there were 2,776 differences in the transcriptome response in cngc16 pollen, consistent with a model in which this heat-sensitive mutant fails to enact or maintain a normal wild-type HSR. In a comparison with apx2 pollen, there were 900 differences in the HSR. Some portion of these 900 differences might contribute to an improved HSR in apx2 pollen. Twenty-seven and 42 transcription factor changes, in cngc16 and apx2-1, respectively, were identified that could provide unique contributions to a pollen HSR. While we found that the functional HS-dependent reprogramming of the pollen transcriptome requires specific activity of CNGC16, we identified in apx2 specific activation of flavonol-biosynthesis pathway and auxin signalling that support a role in pollen thermotolerance. Results from this study have identified metabolic pathways and candidate genes of potential use in improving HS tolerance in pollen. Additionally, we developed new FACS-based methodology that can quantify the stress response for individual pollen in a high-throughput fashion. This technology is being adapted for biological screening of crop plant’s pollen to identify novel thermotolerance traits. Implications, both scientific and agricultural. This study has provided a reference data on the pollen HSR from a model plant, and supports a model that the HSR in pollen has many differences compared to vegetative cells. This provides an important foundation for understanding and improving the pollen HSR, and therefor contributes to the long-term goal of improving productivity in crop plants subjected to temperature stress conditions. A specific hypothesis that has emerged from this study is that pollen thermotolerance can be improved by increasing flavonol accumulation before or during a stress response. Efforts to test this hypothesis have been initiated, and if successful have the potential for application with major seed crops such as maize and rice.
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Wisniewski, Michael, Samir Droby, John Norelli, Dov Prusky et Vera Hershkovitz. Genetic and transcriptomic analysis of postharvest decay resistance in Malus sieversii and the identification of pathogenicity effectors in Penicillium expansum. United States Department of Agriculture, janvier 2012. http://dx.doi.org/10.32747/2012.7597928.bard.
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Use of Lqh2 mutants (produced at TAU) and rNav1.2a mutants (produced at the US side) for identifying receptor site-3: Based on the fact that binding of scorpion alpha-toxins is voltage-dependent, which suggests toxin binding at the mobile voltage-sensing region, we analyzed which of the toxin bioactive domains (Core-domain or NC-domain) interacts with the DIV Gating-module of rNav1.2a. This analysis was based on the assumption that the dissociation of toxin mutants upon depolarization would vary from that of the unmodified toxin should the substitutions affect a site of interaction with the channel Gating-module. Using a series of toxin mutants (mutations at both domains) and two channel mutants that were shown to reduce the sensitivity to scorpion alpha-toxins, and by comparison of depolarization-driven dissociation of Lqh2 derivatives off their binding site at rNav1.2a mutant channels we found that the toxin Core-domain interacts with the Gating-module of DIV. Details of the experiments and results appear in Guret al (2011). Mapping receptor site 3 at Nav1.2a by extensive channel mutagenesis (Seattle): Since previous studies with photoaffinity labeling and antibody mapping implicated domains I and IV in scorpion alpha-toxin binding, Nav1.2 channel mutants containing substitutions at these extracellular regions were expressed and tested for receptor function by whole-cell voltage clamp. Of a large number of channel mutants, T1560A, F1610A, and E1613A in domain IV had ~5.9-, ~10.7-, and ~3.9-fold lower affinities for the scorpion toxin Lqh2, respectively, and mutant E1613R had 73-fold lower affinity. Toxin dissociation was accelerated by depolarization for both wild-type and mutants, and the rates of dissociation were also increased by mutations T1560A, F1610A and E1613A. In contrast, association rates for these three mutant channels at negative membrane potentials were not significantly changed and were not voltage-dependent. These results indicated that Thr1560 in the S1-S2 loop, Phe1610 in the S3 segment, and Glu1613 in the S3-S4 loop in domain IV participate in toxin binding. T393A in the SS2-S6 loop in domain I also showed a ~3.4-fold lower affinity for Lqh2, indicating that this extracellular loop may form a secondary component of the toxin binding site. Analysis with the Rosetta-Membrane algorithm revealed a three-dimensional model of Lqh2 binding to the voltage sensor in a resting state. In this model, amino acid residues in an extracellular cleft formed by the S1-S2 and S3-S4 loops in domain IV that are important for toxin binding interact with amino acid residues on two faces of the wedge-shaped Lqh2 molecule that are important for toxin action. The conserved gating charges in the S4 transmembrane segment are in an inward position and likely form ion pairs with negatively charged amino acid residues in the S2 and S3 segments (Wang et al 2011; Gurevitz 2012; Gurevitzet al 2013).
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Minz, Dror, Stefan J. Green, Noa Sela, Yitzhak Hadar, Janet Jansson et Steven Lindow. Soil and rhizosphere microbiome response to treated waste water irrigation. United States Department of Agriculture, janvier 2013. http://dx.doi.org/10.32747/2013.7598153.bard.
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Research objectives : Identify genetic potential and community structure of soil and rhizosphere microbial community structure as affected by treated wastewater (TWW) irrigation. This objective was achieved through the examination soil and rhizosphere microbial communities of plants irrigated with fresh water (FW) and TWW. Genomic DNA extracted from soil and rhizosphere samples (Minz laboratory) was processed for DNA-based shotgun metagenome sequencing (Green laboratory). High-throughput bioinformatics was performed to compare both taxonomic and functional gene (and pathway) differences between sample types (treatment and location). Identify metabolic pathways induced or repressed by TWW irrigation. To accomplish this objective, shotgun metatranscriptome (RNA-based) sequencing was performed. Expressed genes and pathways were compared to identify significantly differentially expressed features between rhizosphere communities of plants irrigated with FW and TWW. Identify microbial gene functions and pathways affected by TWW irrigation*. To accomplish this objective, we will perform a metaproteome comparison between rhizosphere communities of plants irrigated with FW and TWW and selected soil microbial activities. Integration and evaluation of microbial community function in relation to its structure and genetic potential, and to infer the in situ physiology and function of microbial communities in soil and rhizospere under FW and TWW irrigation regimes. This objective is ongoing due to the need for extensive bioinformatics analysis. As a result of the capabilities of the new PI, we have also been characterizing the transcriptome of the plant roots as affected by the TWW irrigation and comparing the function of the plants to that of the microbiome. *This original objective was not achieved in the course of this study due to technical issues, especially the need to replace the American PIs during the project. However, the fact we were able to analyze more than one plant system as a result of the abilities of the new American PI strengthened the power of the conclusions derived from studies for the 1ˢᵗ and 2ⁿᵈ objectives. Background: As the world population grows, more urban waste is discharged to the environment, and fresh water sources are being polluted. Developing and industrial countries are increasing the use of wastewater and treated wastewater (TWW) for agriculture practice, thus turning the waste product into a valuable resource. Wastewater supplies a year- round reliable source of nutrient-rich water. Despite continuing enhancements in TWW quality, TWW irrigation can still result in unexplained and undesirable effects on crops. In part, these undesirable effects may be attributed to, among other factors, to the effects of TWW on the plant microbiome. Previous studies, including our own, have presented the TWW effect on soil microbial activity and community composition. To the best of our knowledge, however, no comprehensive study yet has been conducted on the microbial population associated BARD Report - Project 4662 Page 2 of 16 BARD Report - Project 4662 Page 3 of 16 with plant roots irrigated with TWW – a critical information gap. In this work, we characterize the effect of TWW irrigation on root-associated microbial community structure and function by using the most innovative tools available in analyzing bacterial community- a combination of microbial marker gene amplicon sequencing, microbial shotunmetagenomics (DNA-based total community and gene content characterization), microbial metatranscriptomics (RNA-based total community and gene content characterization), and plant host transcriptome response. At the core of this research, a mesocosm experiment was conducted to study and characterize the effect of TWW irrigation on tomato and lettuce plants. A focus of this study was on the plant roots, their associated microbial communities, and on the functional activities of plant root-associated microbial communities. We have found that TWW irrigation changes both the soil and root microbial community composition, and that the shift in the plant root microbiome associated with different irrigation was as significant as the changes caused by the plant host or soil type. The change in microbial community structure was accompanied by changes in the microbial community-wide functional potential (i.e., gene content of the entire microbial community, as determined through shotgun metagenome sequencing). The relative abundance of many genes was significantly different in TWW irrigated root microbiome relative to FW-irrigated root microbial communities. For example, the relative abundance of genes encoding for transporters increased in TWW-irrigated roots increased relative to FW-irrigated roots. Similarly, the relative abundance of genes linked to potassium efflux, respiratory systems and nitrogen metabolism were elevated in TWW irrigated roots when compared to FW-irrigated roots. The increased relative abundance of denitrifying genes in TWW systems relative FW systems, suggests that TWW-irrigated roots are more anaerobic compare to FW irrigated root. These gene functional data are consistent with geochemical measurements made from these systems. Specifically, the TWW irrigated soils had higher pH, total organic compound (TOC), sodium, potassium and electric conductivity values in comparison to FW soils. Thus, the root microbiome genetic functional potential can be correlated with pH, TOC and EC values and these factors must take part in the shaping the root microbiome. The expressed functions, as found by the metatranscriptome analysis, revealed many genes that increase in TWW-irrigated plant root microbial population relative to those in the FW-irrigated plants. The most substantial (and significant) were sodium-proton antiporters and Na(+)-translocatingNADH-quinoneoxidoreductase (NQR). The latter protein uses the cell respiratory machinery to harness redox force and convert the energy for efflux of sodium. As the roots and their microbiomes are exposed to the same environmental conditions, it was previously hypothesized that understanding the soil and rhizospheremicrobiome response will shed light on natural processes in these niches. This study demonstrate how newly available tools can better define complex processes and their downstream consequences, such as irrigation with water from different qualities, and to identify primary cues sensed by the plant host irrigated with TWW. From an agricultural perspective, many common practices are complicated processes with many ‘moving parts’, and are hard to characterize and predict. Multiple edaphic and microbial factors are involved, and these can react to many environmental cues. These complex systems are in turn affected by plant growth and exudation, and associated features such as irrigation, fertilization and use of pesticides. However, the combination of shotgun metagenomics, microbial shotgun metatranscriptomics, plant transcriptomics, and physical measurement of soil characteristics provides a mechanism for integrating data from highly complex agricultural systems to eventually provide for plant physiological response prediction and monitoring. BARD Report
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Gelb, Jr., Jack, Yoram Weisman, Brian Ladman et Rosie Meir. Identification of Avian Infectious Brochitis Virus Variant Serotypes and Subtypes by PCR Product Cycle Sequencing for the Rational Selection of Effective Vaccines. United States Department of Agriculture, décembre 2003. http://dx.doi.org/10.32747/2003.7586470.bard.
Texte intégralRésumé :
Objectives 1. Determine the serotypic identities of 40 recent IBV isolates from commercial chickens raised in the USA and Israel. 2. Sequence all IBV field isolates using PCR product cycle sequencing and analyze their S 1 sequence to detennine their homology to other strains in the Genbank and EMBL databases. 3. Select vaccinal strains with the highest S 1 sequence homology to the field isolates and perform challenge of immunity studies in chickens in laboratory trials to detennine level of protection afforded by the vaccines. Background Infectious bronchitis (IB) is a common, economically important disease of the chicken. IB occurs as a respiratory form, associated with airsacculitis, condemnation, and mortality of meat-type broilers, a reproductive form responsible for egg production losses in layers and breeders, and a renal form causing high mortality in broilers and pullets. The causative agent is avian coronavirus infectious bronchitis virus (IBV). Replication of the virus' RNA genome is error-prone and mutations commonly result. A major target for mutation is the gene encoding the spike (S) envelope protein used by the virus to attach and infect the host cell. Mutations in the S gene result in antigenic changes that can lead to the emergence of variant serotypes. The S gene is able to tolerate numerous mutations without compromising the virus' ability to replicate and cause disease. An end result of the virus' "flexibility" is that many strains of IBV are capable of existing in nature. Once formed, new mutant strains, often referred to as variants, are soon subjected to immunological selection so that only the most antigenically novel variants survive in poultry populations. Many novel antigenic variant serotypes and genotypes have been isolated from commercial poultry flocks. Identification of the field isolates of IBV responsible for outbreaks is critical for selecting the appropriate strain(s) for vaccination. Reverse transcriptase polymerase chain reaction (RT-PCR) of the Sl subunit of the envelope spike glycoprotein gene has been a common method used to identify field strains, replacing other time-consuming or less precise tests. Two PCR approaches have been used for identification, restriction fragment length polymorphism (RFLP) and direct automated cycle sequence analysis of a diagnostically relevant hypervariab1e region were compared in our BARD research. Vaccination for IB, although practiced routinely in commercial flocks, is often not protective. Field isolates responsible for outbreaks may be unrelated to the strain(s) used in the vaccination program. However, vaccines may provide varying degrees of cross- protection vs. unrelated field strains so vaccination studies should be performed. Conclusions RFLP and S1 sequence analysis methods were successfully performed using the field isolates from the USA and Israel. Importantly, the S1 sequence analysis method enabled a direct comparison of the genotypes of the field strains by aligning them to sequences in public databases e.g. GenBank. Novel S1 gene sequences were identified in both USA and Israel IBVs but greater diversity was observed in the field isolates from the USA. One novel genotype, characterized in this project, Israel/720/99, is currently being considered for development as an inactivated vaccine. Vaccination with IBV strains in the US (Massachusetts, Arkansas, Delaware 072) or in Israel (Massachusetts, Holland strain) provided higher degrees of cross-protection vs. homologous than heterologous strain challenge. In many cases however, vaccination with two strains (only studies with US strains) produced reasonable cross-protection against heterologous field isolate challenge. Implications S1 sequence analysis provides numerical similarity values and phylogenetic information that can be useful, although by no means conclusive, in developing vaccine control strategies. Identification of many novel S1 genotypes of IBV in the USA is evidence that commercial flocks will be challenged today and in the future with strains unrelated to vaccines. In Israel, monitoring flocks for novel IBV field isolates should continue given the identification of Israel/720/99, and perhaps others in the future. Strains selected for vaccination of commercial flocks should induce cross- protection against unrelated genotypes. Using diverse genotypes for vaccination may result in immunity against unrelated field strains.