Genome-wide comparative analysis of four Indian Drosophila species.

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Mohanty, Sujata; Khanna, Radhika

2017-12-01

Comparative analysis of multiple genomes of closely or distantly related Drosophila species undoubtedly creates excitement among evolutionary biologists in exploring the genomic changes with an ecology and evolutionary perspective. We present herewith the de novo assembled whole genome sequences of four Drosophila species, D. bipectinata, D. takahashii, D. biarmipes and D. nasuta of Indian origin using Next Generation Sequencing technology on an Illumina platform along with their detailed assembly statistics. The comparative genomics analysis, e.g. gene predictions and annotations, functional and orthogroup analysis of coding sequences and genome wide SNP distribution were performed. The whole genome of Zaprionus indianus of Indian origin published earlier by us and the genome sequences of previously sequenced 12 Drosophila species available in the NCBI database were included in the analysis. The present work is a part of our ongoing genomics project of Indian Drosophila species.

Assessing quality and completeness of human transcriptional regulatory pathways on a genome-wide scale

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Aifantis Iannis

2011-02-01

Full Text Available Abstract Background Pathway databases are becoming increasingly important and almost omnipresent in most types of biological and translational research. However, little is known about the quality and completeness of pathways stored in these databases. The present study conducts a comprehensive assessment of transcriptional regulatory pathways in humans for seven well-studied transcription factors: MYC, NOTCH1, BCL6, TP53, AR, STAT1, and RELA. The employed benchmarking methodology first involves integrating genome-wide binding with functional gene expression data to derive direct targets of transcription factors. Then the lists of experimentally obtained direct targets are compared with relevant lists of transcriptional targets from 10 commonly used pathway databases. Results The results of this study show that for the majority of pathway databases, the overlap between experimentally obtained target genes and targets reported in transcriptional regulatory pathway databases is surprisingly small and often is not statistically significant. The only exception is MetaCore pathway database which yields statistically significant intersection with experimental results in 84% cases. Additionally, we suggest that the lists of experimentally derived direct targets obtained in this study can be used to reveal new biological insight in transcriptional regulation and suggest novel putative therapeutic targets in cancer. Conclusions Our study opens a debate on validity of using many popular pathway databases to obtain transcriptional regulatory targets. We conclude that the choice of pathway databases should be informed by solid scientific evidence and rigorous empirical evaluation. Reviewers This article was reviewed by Prof. Wing Hung Wong, Dr. Thiago Motta Venancio (nominated by Dr. L Aravind, and Prof. Geoff J McLachlan.

Genome-wide analysis of the WRKY transcription factors in aegilops tauschii.

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Ma, Jianhui; Zhang, Daijing; Shao, Yun; Liu, Pei; Jiang, Lina; Li, Chunxi

2014-01-01

The WRKY transcription factors (TFs) play important roles in responding to abiotic and biotic stress in plants. However, due to its unfinished genome sequencing, relatively few WRKY TFs with full-length coding sequences (CDSs) have been identified in wheat. Instead, the Aegilops tauschii genome, which is the D-genome progenitor of the hexaploid wheat genome, provides important resources for the discovery of new genes. In this study, we performed a bioinformatics analysis to identify WRKY TFs with full-length CDSs from the A. tauschii genome. A detailed evolutionary analysis for all these TFs was conducted, and quantitative real-time PCR was carried out to investigate the expression patterns of the abiotic stress-related WRKY TFs under different abiotic stress conditions in A. tauschii seedlings. A total of 93 WRKY TFs were identified from A. tauschii, and 79 of them were found to be newly discovered genes compared with wheat. Gene phylogeny, gene structure and chromosome location of the 93 WRKY TFs were fully analyzed. These studies provide a global view of the WRKY TFs from A. tauschii and a firm foundation for further investigations in both A. tauschii and wheat. © 2015 S. Karger AG, Basel.

Genome-wide dynamic transcriptional profiling in clostridium beijerinckii NCIMB 8052 using single-nucleotide resolution RNA-Seq

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Wang Yi

2012-03-01

Full Text Available Abstract Background Clostridium beijerinckii is a prominent solvent-producing microbe that has great potential for biofuel and chemical industries. Although transcriptional analysis is essential to understand gene functions and regulation and thus elucidate proper strategies for further strain improvement, limited information is available on the genome-wide transcriptional analysis for C. beijerinckii. Results The genome-wide transcriptional dynamics of C. beijerinckii NCIMB 8052 over a batch fermentation process was investigated using high-throughput RNA-Seq technology. The gene expression profiles indicated that the glycolysis genes were highly expressed throughout the fermentation, with comparatively more active expression during acidogenesis phase. The expression of acid formation genes was down-regulated at the onset of solvent formation, in accordance with the metabolic pathway shift from acidogenesis to solventogenesis. The acetone formation gene (adc, as a part of the sol operon, exhibited highly-coordinated expression with the other sol genes. Out of the > 20 genes encoding alcohol dehydrogenase in C. beijerinckii, Cbei_1722 and Cbei_2181 were highly up-regulated at the onset of solventogenesis, corresponding to their key roles in primary alcohol production. Most sporulation genes in C. beijerinckii 8052 demonstrated similar temporal expression patterns to those observed in B. subtilis and C. acetobutylicum, while sporulation sigma factor genes sigE and sigG exhibited accelerated and stronger expression in C. beijerinckii 8052, which is consistent with the more rapid forespore and endspore development in this strain. Global expression patterns for specific gene functional classes were examined using self-organizing map analysis. The genes associated with specific functional classes demonstrated global expression profiles corresponding to the cell physiological variation and metabolic pathway switch. Conclusions The results from this

Genome-wide analysis of a Wnt1-regulated transcriptional network implicates neurodegenerative pathways.

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Wexler, Eric M; Rosen, Ezra; Lu, Daning; Osborn, Gregory E; Martin, Elizabeth; Raybould, Helen; Geschwind, Daniel H

2011-10-04

Wnt proteins are critical to mammalian brain development and function. The canonical Wnt signaling pathway involves the stabilization and nuclear translocation of β-catenin; however, Wnt also signals through alternative, noncanonical pathways. To gain a systems-level, genome-wide view of Wnt signaling, we analyzed Wnt1-stimulated changes in gene expression by transcriptional microarray analysis in cultured human neural progenitor (hNP) cells at multiple time points over a 72-hour time course. We observed a widespread oscillatory-like pattern of changes in gene expression, involving components of both the canonical and the noncanonical Wnt signaling pathways. A higher-order, systems-level analysis that combined independent component analysis, waveform analysis, and mutual information-based network construction revealed effects on pathways related to cell death and neurodegenerative disease. Wnt effectors were tightly clustered with presenilin1 (PSEN1) and granulin (GRN), which cause dominantly inherited forms of Alzheimer's disease and frontotemporal dementia (FTD), respectively. We further explored a potential link between Wnt1 and GRN and found that Wnt1 decreased GRN expression by hNPs. Conversely, GRN knockdown increased WNT1 expression, demonstrating that Wnt and GRN reciprocally regulate each other. Finally, we provided in vivo validation of the in vitro findings by analyzing gene expression data from individuals with FTD. These unbiased and genome-wide analyses provide evidence for a connection between Wnt signaling and the transcriptional regulation of neurodegenerative disease genes.

Genome-wide identification and comparative analysis of squamosa-promoter binding proteins (sbp) transcription factor family in gossypium raimondii and arabidopsis thaliana

International Nuclear Information System (INIS)

Ali, M.A.; Alia, K.B.; Atif, R.M.; Rasulj, I.; Nadeem, H.U.; Shahid, A.; Azeem, F

2017-01-01

SQUAMOSA-Promoter Binding Proteins (SBP) are class of transcription factors that play vital role in regulation of plant tissue growth and development. The genes encoding these proteins have not yet been identified in diploid cotton. Thus here, a comprehensive genome wide analysis of SBP genes/proteins was carried out to identify the genes encoding SBP proteins in Gossypium raimondii and Arabidopsis thaliana. We identified 17 SBP genes from Arabidopsis thaliana genome and 30 SBP genes from Gossypium raimondii. Chromosome localization studies revealed the uneven distribution of SBP encoding genes both in the genomes of A. thaliana and G. raimondii. In cotton, five SBP genes were located on chromosome no. 2, while no gene was found on chromosome 9. In A. thaliana, maximum seven SBP genes were identified on chromosome 9, while chromosome 4 did not have any SBP gene. Thus, the SBP gene family might have expanded as a result of segmental as well as tandem duplications in these species. The comparative phylogenetic analysis of Arabidopsis and cotton SBPs revealed the presence of eight groups. The gene structure analysis of SBP encoding genes revealed the presence of one to eleven inrons in both Arabidopsis and G. raimondii. The proteins sharing the same phyletic group mostly demonstrated the similar intron-exon occurrence pattern; and share the common conserved domains. The SBP DNA-binding domain shared 24 absolutely conserved residues in Arabidopsis. The present study can serve as a base for the functional characterization of SBP gene family in Gossypium raimondii. (author)

Genome-wide Reconstruction of OxyR and SoxRS Transcriptional Regulatory Networks under Oxidative Stress in Escherichia coli K-12 MG1655

DEFF Research Database (Denmark)

Seo, Sang Woo; Kim, Donghyuk; Szubin, Richard

2015-01-01

Three transcription factors (TFs), OxyR, SoxR, and SoxS, play a critical role in transcriptional regulation of the defense system for oxidative stress in bacteria. However, their full genome-wide regulatory potential is unknown. Here, we perform a genome-scale reconstruction of the OxyR, SoxR, an...

Genome-Wide Identification of the Target Genes of AP2-O, a Plasmodium AP2-Family Transcription Factor.

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Izumi Kaneko

2015-05-01

Full Text Available Stage-specific transcription is a fundamental biological process in the life cycle of the Plasmodium parasite. Proteins containing the AP2 DNA-binding domain are responsible for stage-specific transcriptional regulation and belong to the only known family of transcription factors in Plasmodium parasites. Comprehensive identification of their target genes will advance our understanding of the molecular basis of stage-specific transcriptional regulation and stage-specific parasite development. AP2-O is an AP2 family transcription factor that is expressed in the mosquito midgut-invading stage, called the ookinete, and is essential for normal morphogenesis of this stage. In this study, we identified the genome-wide target genes of AP2-O by chromatin immunoprecipitation-sequencing and elucidate how this AP2 family transcription factor contributes to the formation of this motile stage. The analysis revealed that AP2-O binds specifically to the upstream genomic regions of more than 500 genes, suggesting that approximately 10% of the parasite genome is directly regulated by AP2-O. These genes are involved in distinct biological processes such as morphogenesis, locomotion, midgut penetration, protection against mosquito immunity and preparation for subsequent oocyst development. This direct and global regulation by AP2-O provides a model for gene regulation in Plasmodium parasites and may explain how these parasites manage to control their complex life cycle using a small number of sequence-specific AP2 transcription factors.

Genome-wide specificity of DNA binding, gene regulation, and chromatin remodeling by TALE- and CRISPR/Cas9-based transcriptional activators.

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Polstein, Lauren R; Perez-Pinera, Pablo; Kocak, D Dewran; Vockley, Christopher M; Bledsoe, Peggy; Song, Lingyun; Safi, Alexias; Crawford, Gregory E; Reddy, Timothy E; Gersbach, Charles A

2015-08-01

Genome engineering technologies based on the CRISPR/Cas9 and TALE systems are enabling new approaches in science and biotechnology. However, the specificity of these tools in complex genomes and the role of chromatin structure in determining DNA binding are not well understood. We analyzed the genome-wide effects of TALE- and CRISPR-based transcriptional activators in human cells using ChIP-seq to assess DNA-binding specificity and RNA-seq to measure the specificity of perturbing the transcriptome. Additionally, DNase-seq was used to assess genome-wide chromatin remodeling that occurs as a result of their action. Our results show that these transcription factors are highly specific in both DNA binding and gene regulation and are able to open targeted regions of closed chromatin independent of gene activation. Collectively, these results underscore the potential for these technologies to make precise changes to gene expression for gene and cell therapies or fundamental studies of gene function. © 2015 Polstein et al.; Published by Cold Spring Harbor Laboratory Press.

Genome wide transcriptional response of Saccharomyces cerevisiae to stress-induced perturbations

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Hilal eTaymaz-Nikerel

2016-02-01

Full Text Available Cells respond to environmental and/or genetic perturbations in order to survive and proliferate. Characterization of the changes after various stimuli at different -omics levels is crucial to comprehend the adaptation of cells to changing conditions. Genome wide quantification and analysis of transcript levels, the genes affected by perturbations, extends our understanding of cellular metabolism by pointing out the mechanisms that play role in sensing the stress caused by those perturbations and related signaling pathways, and in this way guides us to achieve endeavors such as rational engineering of cells or interpretation of disease mechanisms. Saccharomyces cerevisiae as a model system has been studied in response to different perturbations and corresponding transcriptional profiles were followed either statically or/and dynamically, short- and long- term. This review focuses on response of yeast cells to diverse stress inducing perturbations including nutritional changes, ionic stress, salt stress, oxidative stress, osmotic shock, as well as to genetic interventions such as deletion and over-expression of genes. It is aimed to conclude on common regulatory phenomena that allow yeast to organize its transcriptomic response after any perturbation under different external conditions.

Genome-wide transcriptional reorganization associated with senescence-to-immortality switch during human hepatocellular carcinogenesis.

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Gokhan Yildiz

Full Text Available Senescence is a permanent proliferation arrest in response to cell stress such as DNA damage. It contributes strongly to tissue aging and serves as a major barrier against tumor development. Most tumor cells are believed to bypass the senescence barrier (become "immortal" by inactivating growth control genes such as TP53 and CDKN2A. They also reactivate telomerase reverse transcriptase. Senescence-to-immortality transition is accompanied by major phenotypic and biochemical changes mediated by genome-wide transcriptional modifications. This appears to happen during hepatocellular carcinoma (HCC development in patients with liver cirrhosis, however, the accompanying transcriptional changes are virtually unknown. We investigated genome-wide transcriptional changes related to the senescence-to-immortality switch during hepatocellular carcinogenesis. Initially, we performed transcriptome analysis of senescent and immortal clones of Huh7 HCC cell line, and identified genes with significant differential expression to establish a senescence-related gene list. Through the analysis of senescence-related gene expression in different liver tissues we showed that cirrhosis and HCC display expression patterns compatible with senescent and immortal phenotypes, respectively; dysplasia being a transitional state. Gene set enrichment analysis revealed that cirrhosis/senescence-associated genes were preferentially expressed in non-tumor tissues, less malignant tumors, and differentiated or senescent cells. In contrast, HCC/immortality genes were up-regulated in tumor tissues, or more malignant tumors and progenitor cells. In HCC tumors and immortal cells genes involved in DNA repair, cell cycle, telomere extension and branched chain amino acid metabolism were up-regulated, whereas genes involved in cell signaling, as well as in drug, lipid, retinoid and glycolytic metabolism were down-regulated. Based on these distinctive gene expression features we developed a 15

Rapid Genome-wide Recruitment of RNA Polymerase II Drives Transcription, Splicing, and Translation Events during T Cell Responses

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Kathrin Davari

2017-04-01

Full Text Available Summary: Activation of immune cells results in rapid functional changes, but how such fast changes are accomplished remains enigmatic. By combining time courses of 4sU-seq, RNA-seq, ribosome profiling (RP, and RNA polymerase II (RNA Pol II ChIP-seq during T cell activation, we illustrate genome-wide temporal dynamics for ∼10,000 genes. This approach reveals not only immediate-early and posttranscriptionally regulated genes but also coupled changes in transcription and translation for >90% of genes. Recruitment, rather than release of paused RNA Pol II, primarily mediates transcriptional changes. This coincides with a genome-wide temporary slowdown in cotranscriptional splicing, even for polyadenylated mRNAs that are localized at the chromatin. Subsequent splicing optimization correlates with increasing Ser-2 phosphorylation of the RNA Pol II carboxy-terminal domain (CTD and activation of the positive transcription elongation factor (pTEFb. Thus, rapid de novo recruitment of RNA Pol II dictates the course of events during T cell activation, particularly transcription, splicing, and consequently translation. : Davari et al. visualize global changes in RNA Pol II binding, transcription, splicing, and translation. T cells change their functional program by rapid de novo recruitment of RNA Pol II and coupled changes in transcription and translation. This coincides with fluctuations in RNA Pol II phosphorylation and a temporary reduction in cotranscriptional splicing. Keywords: RNA Pol II, cotranscriptional splicing, T cell activation, ribosome profiling, 4sU, H3K36, Ser-5 RNA Pol II, Ser-2 RNA Pol II, immune response, immediate-early genes

Nitrogen fixation and molecular oxygen: comparative genomic reconstruction of transcription regulation in Alphaproteobacteria

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Olga V Tsoy

2016-08-01

Full Text Available Biological nitrogen fixation plays a crucial role in the nitrogen cycle. An ability to fix atmospheric nitrogen, reducing it to ammonium, was described for multiple species of Bacteria and Archaea. Being a complex and sensitive process, nitrogen fixation requires a complicated regulatory system, also, on the level of transcription. The transcriptional regulatory network for nitrogen fixation was extensively studied in several representatives of the class Alphaproteobacteria. This regulatory network includes the activator of nitrogen fixation NifA, working in tandem with the alternative sigma-factor RpoN as well as oxygen-responsive regulatory systems, one-component regulators FnrN/FixK and two-component system FixLJ. Here we used a comparative genomics analysis for in silico study of the transcriptional regulatory network in 50 genomes of Alphaproteobacteria. We extended the known regulons and proposed the scenario for the evolution of the nitrogen fixation transcriptional network. The reconstructed network substantially expands the existing knowledge of transcriptional regulation in nitrogen-fixing microorganisms and can be used for genetic experiments, metabolic reconstruction, and evolutionary analysis.

Genome-wide screening and transcriptional profile analysis of desaturase genes in the European corn borer moth

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Bingye Xue; Alejandro P. Rooney; Wendell L. Roelofs

2012-01-01

Acyl-coenzyme A (Acyl-CoA) desaturases play a key role in the biosynthesis of female moth sex pheromones.Desaturase genes are encoded by a large multigene family,and they have been divided into five subgroups on the basis of biochemical functionality and phylogenetic affinity.In this study both copy numbers and transcriptional levels of desaturase genes in the European corn borer (ECB),Ostrinia nubilalis,were investigated.The results from genome-wide screening of ECB bacterial artificial chromosome (BAC)library indicated there are many copies of some desaturase genes in the genome.An open reading frame (ORF) has been isolated for the novel desaturase gene ECB ezi-△11β from ECB gland complementary DNA and its functionality has been analyzed by two yeast expression systems.No functional activities have been detected for it.The expression levels of the four desaturase genes both in the pheromone gland and fat body of ECB and Asian corn borer (ACB),O.furnacalis,were determined by real-time polymerase chain reaction.In the ECB gland,△ 11 is the most abundant,although the amount of △14 is also considerable.In the ACB gland,△14 is the most abundant and is 100 times more abundant than all the other three combined.The results from the analysis of evolution of desaturase gene transcription in the ECB,ACB and other moths indicate that the pattern of △ 11 gene transcription is significantly different from the transcriptional patterns of other desaturase genes and this difference is tied to the underlying nucleotide composition bias of the genome.

Genome-wide analysis of EgEVE_1, a transcriptionally active endogenous viral element associated to small RNAs in Eucalyptus genomes

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Helena Sanches Marcon

2017-02-01

Full Text Available Abstract Endogenous viral elements (EVEs are the result of heritable horizontal gene transfer from viruses to hosts. In the last years, several EVE integration events were reported in plants by the exponential availability of sequenced genomes. Eucalyptus grandis is a forest tree species with a sequenced genome that is poorly studied in terms of evolution and mobile genetic elements composition. Here we report the characterization of E. grandis endogenous viral element 1 (EgEVE_1, a transcriptionally active EVE with a size of 5,664 bp. Phylogenetic analysis and genomic distribution demonstrated that EgEVE_1 is a newly described member of the Caulimoviridae family, distinct from the recently characterized plant Florendoviruses. Genomic distribution of EgEVE_1 and Florendovirus is also distinct. EgEVE_1 qPCR quantification in Eucalyptus urophylla suggests that this genome has more EgEVE_1 copies than E. grandis. EgEVE_1 transcriptional activity was demonstrated by RT-qPCR in five Eucalyptus species and one intrageneric hybrid. We also identified that Eucalyptus EVEs can generate small RNAs (sRNAs,that might be involved in de novo DNA methylation and virus resistance. Our data suggest that EVE families in Eucalyptus have distinct properties, and we provide the first comparative analysis of EVEs in Eucalyptus genomes.

Genome-wide Reconstruction of OxyR and SoxRS Transcriptional Regulatory Networks under Oxidative Stress in Escherichia coli K-12 MG1655

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Sang Woo Seo

2015-08-01

Full Text Available Three transcription factors (TFs, OxyR, SoxR, and SoxS, play a critical role in transcriptional regulation of the defense system for oxidative stress in bacteria. However, their full genome-wide regulatory potential is unknown. Here, we perform a genome-scale reconstruction of the OxyR, SoxR, and SoxS regulons in Escherichia coli K-12 MG1655. Integrative data analysis reveals that a total of 68 genes in 51 transcription units (TUs belong to these regulons. Among them, 48 genes showed more than 2-fold changes in expression level under single-TF-knockout conditions. This reconstruction expands the genome-wide roles of these factors to include direct activation of genes related to amino acid biosynthesis (methionine and aromatic amino acids, cell wall synthesis (lipid A biosynthesis and peptidoglycan growth, and divalent metal ion transport (Mn2+, Zn2+, and Mg2+. Investigating the co-regulation of these genes with other stress-response TFs reveals that they are independently regulated by stress-specific TFs.

Genome-wide transcriptional profiling of human glioblastoma cells in response to ITE treatment.

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Kang, Bo; Zhou, Yanwen; Zheng, Min; Wang, Ying-Jie

2015-09-01

A ligand-activated transcription factor aryl hydrocarbon receptor (AhR) is recently revealed to play a key role in embryogenesis and tumorigenesis (Feng et al. [1], Safe et al. [2]) and 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) (Song et al. [3]) is an endogenous AhR ligand that possesses anti-tumor activity. In order to gain insights into how ITE acts via the AhR in embryogenesis and tumorigenesis, we analyzed the genome-wide transcriptional profiles of the following three groups of cells: the human glioblastoma U87 parental cells, U87 tumor sphere cells treated with vehicle (DMSO) and U87 tumor sphere cells treated with ITE. Here, we provide the details of the sample gathering strategy and show the quality controls and the analyses associated with our gene array data deposited into the Gene Expression Omnibus (GEO) under the accession code of GSE67986.

Genome-wide investigation of transcription factors provides insights into transcriptional regulation in Plutella xylostella.

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Zhao, Qian; Ma, Dongna; Huang, Yuping; He, Weiyi; Li, Yiying; Vasseur, Liette; You, Minsheng

2018-04-01

Transcription factors (TFs), which play a vital role in regulating gene expression, are prevalent in all organisms and characterization of them may provide important clues for understanding regulation in vivo. The present study reports a genome-wide investigation of TFs in the diamondback moth, Plutella xylostella (L.), a worldwide pest of crucifers. A total of 940 TFs distributed among 133 families were identified. Phylogenetic analysis of insect species showed that some of these families were found to have expanded during the evolution of P. xylostella or Lepidoptera. RNA-seq analysis showed that some of the TF families, such as zinc fingers, homeobox, bZIP, bHLH, and MADF_DNA_bdg genes, were highly expressed in certain tissues including midgut, salivary glands, fat body, and hemocytes, with an obvious sex-biased expression pattern. In addition, a number of TFs showed significant differences in expression between insecticide susceptible and resistant strains, suggesting that these TFs play a role in regulating genes related to insecticide resistance. Finally, we identified an expansion of the HOX cluster in Lepidoptera, which might be related to Lepidoptera-specific evolution. Knockout of this cluster using CRISPR/Cas9 showed that the egg cannot hatch, indicating that this cluster may be related to egg development and maturation. This is the first comprehensive study on identifying and characterizing TFs in P. xylostella. Our results suggest that some TF families are expanded in the P. xylostella genome, and these TFs may have important biological roles in growth, development, sexual dimorphism, and resistance to insecticides. The present work provides a solid foundation for understanding regulation via TFs in P. xylostella and insights into the evolution of the P. xylostella genome.

Genome-wide transcription responses to synchrotron microbeam radiotherapy.

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Sprung, Carl N; Yang, Yuqing; Forrester, Helen B; Li, Jason; Zaitseva, Marina; Cann, Leonie; Restall, Tina; Anderson, Robin L; Crosbie, Jeffrey C; Rogers, Peter A W

2012-10-01

The majority of cancer patients achieve benefit from radiotherapy. A significant limitation of radiotherapy is its relatively low therapeutic index, defined as the maximum radiation dose that causes acceptable normal tissue damage to the minimum dose required to achieve tumor control. Recently, a new radiotherapy modality using synchrotron-generated X-ray microbeam radiotherapy has been demonstrated in animal models to ablate tumors with concurrent sparing of normal tissue. Very little work has been undertaken into the cellular and molecular mechanisms that differentiate microbeam radiotherapy from broad beam. The purpose of this study was to investigate and compare the whole genome transcriptional response of in vivo microbeam radiotherapy versus broad beam irradiated tumors. We hypothesized that gene expression changes after microbeam radiotherapy are different from those seen after broad beam. We found that in EMT6.5 tumors at 4-48 h postirradiation, microbeam radiotherapy differentially regulates a number of genes, including major histocompatibility complex (MHC) class II antigen gene family members, and other immunity-related genes including Ciita, Ifng, Cxcl1, Cxcl9, Indo and Ubd when compared to broad beam. Our findings demonstrate molecular differences in the tumor response to microbeam versus broad beam irradiation and these differences provide insight into the underlying mechanisms of microbeam radiotherapy and broad beam.

Genome-wide mapping of boundary element-associated factor (BEAF) binding sites in Drosophila melanogaster links BEAF to transcription.

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Jiang, Nan; Emberly, Eldon; Cuvier, Olivier; Hart, Craig M

2009-07-01

Insulator elements play a role in gene regulation that is potentially linked to nuclear organization. Boundary element-associated factors (BEAFs) 32A and 32B associate with hundreds of sites on Drosophila polytene chromosomes. We hybridized DNA isolated by chromatin immunoprecipitation to genome tiling microarrays to construct a genome-wide map of BEAF binding locations. A distinct difference in the association of 32A and 32B with chromatin was noted. We identified 1,820 BEAF peaks and found that more than 85% were less than 300 bp from transcription start sites. Half are between head-to-head gene pairs. BEAF-associated genes are transcriptionally active as judged by the presence of RNA polymerase II, dimethylated histone H3 K4, and the alternative histone H3.3. Forty percent of these genes are also associated with the polymerase negative elongation factor NELF. Like NELF-associated genes, most BEAF-associated genes are highly expressed. Using quantitative reverse transcription-PCR, we found that the expression levels of most BEAF-associated genes decrease in embryos and cultured cells lacking BEAF. These results provide an unexpected link between BEAF and transcription, suggesting that BEAF plays a role in maintaining most associated promoter regions in an environment that facilitates high transcription levels.

Genome-wide association between DNA methylation and alternative splicing in an invertebrate

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Flores Kevin

2012-09-01

Full Text Available Abstract Background Gene bodies are the most evolutionarily conserved targets of DNA methylation in eukaryotes. However, the regulatory functions of gene body DNA methylation remain largely unknown. DNA methylation in insects appears to be primarily confined to exons. Two recent studies in Apis mellifera (honeybee and Nasonia vitripennis (jewel wasp analyzed transcription and DNA methylation data for one gene in each species to demonstrate that exon-specific DNA methylation may be associated with alternative splicing events. In this study we investigated the relationship between DNA methylation, alternative splicing, and cross-species gene conservation on a genome-wide scale using genome-wide transcription and DNA methylation data. Results We generated RNA deep sequencing data (RNA-seq to measure genome-wide mRNA expression at the exon- and gene-level. We produced a de novo transcriptome from this RNA-seq data and computationally predicted splice variants for the honeybee genome. We found that exons that are included in transcription are higher methylated than exons that are skipped during transcription. We detected enrichment for alternative splicing among methylated genes compared to unmethylated genes using fisher’s exact test. We performed a statistical analysis to reveal that the presence of DNA methylation or alternative splicing are both factors associated with a longer gene length and a greater number of exons in genes. In concordance with this observation, a conservation analysis using BLAST revealed that each of these factors is also associated with higher cross-species gene conservation. Conclusions This study constitutes the first genome-wide analysis exhibiting a positive relationship between exon-level DNA methylation and mRNA expression in the honeybee. Our finding that methylated genes are enriched for alternative splicing suggests that, in invertebrates, exon-level DNA methylation may play a role in the construction of splice

Genome-Wide Identification and Expression Analysis of WRKY Transcription Factors under Multiple Stresses in Brassica napus.

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He, Yajun; Mao, Shaoshuai; Gao, Yulong; Zhu, Liying; Wu, Daoming; Cui, Yixin; Li, Jiana; Qian, Wei

2016-01-01

WRKY transcription factors play important roles in responses to environmental stress stimuli. Using a genome-wide domain analysis, we identified 287 WRKY genes with 343 WRKY domains in the sequenced genome of Brassica napus, 139 in the A sub-genome and 148 in the C sub-genome. These genes were classified into eight groups based on phylogenetic analysis. In the 343 WRKY domains, a total of 26 members showed divergence in the WRKY domain, and 21 belonged to group I. This finding suggested that WRKY genes in group I are more active and variable compared with genes in other groups. Using genome-wide identification and analysis of the WRKY gene family in Brassica napus, we observed genome duplication, chromosomal/segmental duplications and tandem duplication. All of these duplications contributed to the expansion of the WRKY gene family. The duplicate segments that were detected indicated that genome duplication events occurred in the two diploid progenitors B. rapa and B. olearecea before they combined to form B. napus. Analysis of the public microarray database and EST database for B. napus indicated that 74 WRKY genes were induced or preferentially expressed under stress conditions. According to the public QTL data, we identified 77 WRKY genes in 31 QTL regions related to various stress tolerance. We further evaluated the expression of 26 BnaWRKY genes under multiple stresses by qRT-PCR. Most of the genes were induced by low temperature, salinity and drought stress, indicating that the WRKYs play important roles in B. napus stress responses. Further, three BnaWRKY genes were strongly responsive to the three multiple stresses simultaneously, which suggests that these 3 WRKY may have multi-functional roles in stress tolerance and can potentially be used in breeding new rapeseed cultivars. We also found six tandem repeat pairs exhibiting similar expression profiles under the various stress conditions, and three pairs were mapped in the stress related QTL regions

Genome-Wide Identification and Expression Analysis of WRKY Transcription Factors under Multiple Stresses in Brassica napus.

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Yajun He

Full Text Available WRKY transcription factors play important roles in responses to environmental stress stimuli. Using a genome-wide domain analysis, we identified 287 WRKY genes with 343 WRKY domains in the sequenced genome of Brassica napus, 139 in the A sub-genome and 148 in the C sub-genome. These genes were classified into eight groups based on phylogenetic analysis. In the 343 WRKY domains, a total of 26 members showed divergence in the WRKY domain, and 21 belonged to group I. This finding suggested that WRKY genes in group I are more active and variable compared with genes in other groups. Using genome-wide identification and analysis of the WRKY gene family in Brassica napus, we observed genome duplication, chromosomal/segmental duplications and tandem duplication. All of these duplications contributed to the expansion of the WRKY gene family. The duplicate segments that were detected indicated that genome duplication events occurred in the two diploid progenitors B. rapa and B. olearecea before they combined to form B. napus. Analysis of the public microarray database and EST database for B. napus indicated that 74 WRKY genes were induced or preferentially expressed under stress conditions. According to the public QTL data, we identified 77 WRKY genes in 31 QTL regions related to various stress tolerance. We further evaluated the expression of 26 BnaWRKY genes under multiple stresses by qRT-PCR. Most of the genes were induced by low temperature, salinity and drought stress, indicating that the WRKYs play important roles in B. napus stress responses. Further, three BnaWRKY genes were strongly responsive to the three multiple stresses simultaneously, which suggests that these 3 WRKY may have multi-functional roles in stress tolerance and can potentially be used in breeding new rapeseed cultivars. We also found six tandem repeat pairs exhibiting similar expression profiles under the various stress conditions, and three pairs were mapped in the stress related

In silico comparative genomic analysis of GABAA receptor transcriptional regulation

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Joyce Christopher J

2007-06-01

Full Text Available Abstract Background Subtypes of the GABAA receptor subunit exhibit diverse temporal and spatial expression patterns. In silico comparative analysis was used to predict transcriptional regulatory features in individual mammalian GABAA receptor subunit genes, and to identify potential transcriptional regulatory components involved in the coordinate regulation of the GABAA receptor gene clusters. Results Previously unreported putative promoters were identified for the β2, γ1, γ3, ε, θ and π subunit genes. Putative core elements and proximal transcriptional factors were identified within these predicted promoters, and within the experimentally determined promoters of other subunit genes. Conserved intergenic regions of sequence in the mammalian GABAA receptor gene cluster comprising the α1, β2, γ2 and α6 subunits were identified as potential long range transcriptional regulatory components involved in the coordinate regulation of these genes. A region of predicted DNase I hypersensitive sites within the cluster may contain transcriptional regulatory features coordinating gene expression. A novel model is proposed for the coordinate control of the gene cluster and parallel expression of the α1 and β2 subunits, based upon the selective action of putative Scaffold/Matrix Attachment Regions (S/MARs. Conclusion The putative regulatory features identified by genomic analysis of GABAA receptor genes were substantiated by cross-species comparative analysis and now require experimental verification. The proposed model for the coordinate regulation of genes in the cluster accounts for the head-to-head orientation and parallel expression of the α1 and β2 subunit genes, and for the disruption of transcription caused by insertion of a neomycin gene in the close vicinity of the α6 gene, which is proximal to a putative critical S/MAR.

Genome-wide Expression Analysis and Metabolite Profiling Elucidate Transcriptional Regulation of Flavonoid Biosynthesis and Modulation under Abiotic Stresses in Banana.

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Pandey, Ashutosh; Alok, Anshu; Lakhwani, Deepika; Singh, Jagdeep; Asif, Mehar H; Trivedi, Prabodh K

2016-08-19

Flavonoid biosynthesis is largely regulated at the transcriptional level due to the modulated expression of genes related to the phenylpropanoid pathway in plants. Although accumulation of different flavonoids has been reported in banana, a staple fruit crop, no detailed information is available on regulation of the biosynthesis in this important plant. We carried out genome-wide analysis of banana (Musa acuminata, AAA genome) and identified 28 genes belonging to 9 gene families associated with flavonoid biosynthesis. Expression analysis suggested spatial and temporal regulation of the identified genes in different tissues of banana. Analysis revealed enhanced expression of genes related to flavonol and proanthocyanidin (PA) biosynthesis in peel and pulp at the early developmental stages of fruit. Genes involved in anthocyanin biosynthesis were highly expressed during banana fruit ripening. In general, higher accumulation of metabolites was observed in the peel as compared to pulp tissue. A correlation between expression of genes and metabolite content was observed at the early stage of fruit development. Furthermore, this study also suggests regulation of flavonoid biosynthesis, at transcriptional level, under light and dark exposures as well as methyl jasmonate (MJ) treatment in banana.

RegPrecise 3.0--a resource for genome-scale exploration of transcriptional regulation in bacteria.

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Novichkov, Pavel S; Kazakov, Alexey E; Ravcheev, Dmitry A; Leyn, Semen A; Kovaleva, Galina Y; Sutormin, Roman A; Kazanov, Marat D; Riehl, William; Arkin, Adam P; Dubchak, Inna; Rodionov, Dmitry A

2013-11-01

Genome-scale prediction of gene regulation and reconstruction of transcriptional regulatory networks in prokaryotes is one of the critical tasks of modern genomics. Bacteria from different taxonomic groups, whose lifestyles and natural environments are substantially different, possess highly diverged transcriptional regulatory networks. The comparative genomics approaches are useful for in silico reconstruction of bacterial regulons and networks operated by both transcription factors (TFs) and RNA regulatory elements (riboswitches). RegPrecise (http://regprecise.lbl.gov) is a web resource for collection, visualization and analysis of transcriptional regulons reconstructed by comparative genomics. We significantly expanded a reference collection of manually curated regulons we introduced earlier. RegPrecise 3.0 provides access to inferred regulatory interactions organized by phylogenetic, structural and functional properties. Taxonomy-specific collections include 781 TF regulogs inferred in more than 160 genomes representing 14 taxonomic groups of Bacteria. TF-specific collections include regulogs for a selected subset of 40 TFs reconstructed across more than 30 taxonomic lineages. Novel collections of regulons operated by RNA regulatory elements (riboswitches) include near 400 regulogs inferred in 24 bacterial lineages. RegPrecise 3.0 provides four classifications of the reference regulons implemented as controlled vocabularies: 55 TF protein families; 43 RNA motif families; ~150 biological processes or metabolic pathways; and ~200 effectors or environmental signals. Genome-wide visualization of regulatory networks and metabolic pathways covered by the reference regulons are available for all studied genomes. A separate section of RegPrecise 3.0 contains draft regulatory networks in 640 genomes obtained by an conservative propagation of the reference regulons to closely related genomes. RegPrecise 3.0 gives access to the transcriptional regulons reconstructed in

Genome-wide transcriptional responses of Alteromonas naphthalenivorans SN2 to contaminated seawater and marine tidal flat sediment.

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Jin, Hyun Mi; Jeong, Hye Im; Kim, Kyung Hyun; Hahn, Yoonsoo; Madsen, Eugene L; Jeon, Che Ok

2016-02-18

A genome-wide transcriptional analysis of Alteromonas naphthalenivorans SN2 was performed to investigate its ecophysiological behavior in contaminated tidal flats and seawater. The experimental design mimicked these habitats that either added naphthalene or pyruvate; tidal flat-naphthalene (TF-N), tidal flat-pyruvate (TF-P), seawater-naphthalene (SW-N), and seawater-pyruvate (SW-P). The transcriptional profiles clustered by habitat (TF-N/TF-P and SW-N/SW-P), rather than carbon source, suggesting that the former may exert a greater influence on genome-wide expression in strain SN2 than the latter. Metabolic mapping of cDNA reads from strain SN2 based on KEGG pathway showed that metabolic and regulatory genes associated with energy metabolism, translation, and cell motility were highly expressed in all four test conditions, probably highlighting the copiotrophic properties of strain SN2 as an opportunistic marine r-strategist. Differential gene expression analysis revealed that strain SN2 displayed specific cellular responses to environmental variables (tidal flat, seawater, naphthalene, and pyruvate) and exhibited certain ecological fitness traits -- its notable PAH degradation capability in seasonally cold tidal flat might be reflected in elevated expression of stress response and chaperone proteins, while fast growth in nitrogen-deficient and aerobic seawater probably correlated with high expression of glutamine synthetase, enzymes utilizing nitrite/nitrate, and those involved in the removal of reactive oxygen species.

Decoding genome-wide GadEWX-transcriptional regulatory networks reveals multifaceted cellular responses to acid stress in Escherichia coli

DEFF Research Database (Denmark)

Seo, Sang Woo; Kim, Donghyuk; O'Brien, Edward J.

2015-01-01

The regulators GadE, GadW and GadX (which we refer to as GadEWX) play a critical role in the transcriptional regulation of the glutamate-dependent acid resistance (GDAR) system in Escherichia coli K-12 MG1655. However, the genome-wide regulatory role of GadEWX is still unknown. Here we comprehens...

Genome-wide profiling of H3K56 acetylation and transcription factor binding sites in human adipocytes.

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Kinyui Alice Lo

Full Text Available The growing epidemic of obesity and metabolic diseases calls for a better understanding of adipocyte biology. The regulation of transcription in adipocytes is particularly important, as it is a target for several therapeutic approaches. Transcriptional outcomes are influenced by both histone modifications and transcription factor binding. Although the epigenetic states and binding sites of several important transcription factors have been profiled in the mouse 3T3-L1 cell line, such data are lacking in human adipocytes. In this study, we identified H3K56 acetylation sites in human adipocytes derived from mesenchymal stem cells. H3K56 is acetylated by CBP and p300, and deacetylated by SIRT1, all are proteins with important roles in diabetes and insulin signaling. We found that while almost half of the genome shows signs of H3K56 acetylation, the highest level of H3K56 acetylation is associated with transcription factors and proteins in the adipokine signaling and Type II Diabetes pathways. In order to discover the transcription factors that recruit acetyltransferases and deacetylases to sites of H3K56 acetylation, we analyzed DNA sequences near H3K56 acetylated regions and found that the E2F recognition sequence was enriched. Using chromatin immunoprecipitation followed by high-throughput sequencing, we confirmed that genes bound by E2F4, as well as those by HSF-1 and C/EBPα, have higher than expected levels of H3K56 acetylation, and that the transcription factor binding sites and acetylation sites are often adjacent but rarely overlap. We also discovered a significant difference between bound targets of C/EBPα in 3T3-L1 and human adipocytes, highlighting the need to construct species-specific epigenetic and transcription factor binding site maps. This is the first genome-wide profile of H3K56 acetylation, E2F4, C/EBPα and HSF-1 binding in human adipocytes, and will serve as an important resource for better understanding adipocyte

Genome-wide systematic characterization of the bZIP transcriptional factor family in tomato (Solanum lycopersicum L.).

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Li, Dayong; Fu, Fuyou; Zhang, Huijuan; Song, Fengming

2015-10-12

Transcription factors of the basic leucine zipper (bZIP) family represent exclusively in eukaryotes and have been shown to regulate diverse biological processes in plant growth and development as well as in abiotic and biotic stress responses. However, little is known about the bZIP family in tomato (Solanum lycopersicum L.). The SlbZIP genes were identified using local BLAST and hidden Markov model profile searches. The phylogenetic trees, conserved motifs and gene structures were generated by MEGA6.06, MEME tool and gene Structure Display Server, respectively. The syntenic block diagrams were generated by the Circos software. The transcriptional gene expression profiles were obtained using Genevestigator tool and quantitative RT-PCR. In the present study, we carried out a genome-wide identification and systematic analyses of 69 SlbZIP genes that distributes unevenly on the tomato chromosomes. This family can be divided into 9 groups according to the phylogenetic relationship among the SlbZIP proteins. Six kinds of intron patterns (a-f) within the basic and hinge regions are defined. The additional conserved motifs and their presence of the group specificity were also identified. Further, we predicted the DNA-binding patterns and the dimerization property on the basis of the characteristic features in the basic and hinge regions and the leucine zipper, respectively, which supports our classification greatly and helps to classify 24 distinct subfamilies. Within the SlbZIP family, a total of 40 SlbZIP genes are located in the segmental duplicate regions in the tomato genome, suggesting that the segment chromosomal duplications contribute greatly to the expansion of the tomato SlbZIP family. Expression profiling analyses of 59 SlbZIP genes using quantitative RT-PCR and publicly available microarray data indicate that the tomato SlbZIP genes have distinct and diverse expression patterns in different tissues and developmental stages and many of the tomato bZIP genes

Induced Genome-Wide Binding of Three Arabidopsis WRKY Transcription Factors during Early MAMP-Triggered Immunity.

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Birkenbihl, Rainer P; Kracher, Barbara; Somssich, Imre E

2017-01-01

During microbial-associated molecular pattern-triggered immunity (MTI), molecules derived from microbes are perceived by cell surface receptors and upon signaling to the nucleus initiate a massive transcriptional reprogramming critical to mount an appropriate host defense response. WRKY transcription factors play an important role in regulating these transcriptional processes. Here, we determined on a genome-wide scale the flg22-induced in vivo DNA binding dynamics of three of the most prominent WRKY factors, WRKY18, WRKY40, and WRKY33. The three WRKY factors each bound to more than 1000 gene loci predominantly at W-box elements, the known WRKY binding motif. Binding occurred mainly in the 500-bp promoter regions of these genes. Many of the targeted genes are involved in signal perception and transduction not only during MTI but also upon damage-associated molecular pattern-triggered immunity, providing a mechanistic link between these functionally interconnected basal defense pathways. Among the additional targets were genes involved in the production of indolic secondary metabolites and in modulating distinct plant hormone pathways. Importantly, among the targeted genes were numerous transcription factors, encoding predominantly ethylene response factors, active during early MTI, and WRKY factors, supporting the previously hypothesized existence of a WRKY subregulatory network. Transcriptional analysis revealed that WRKY18 and WRKY40 function redundantly as negative regulators of flg22-induced genes often to prevent exaggerated defense responses. © 2016 American Society of Plant Biologists. All rights reserved.

Genomic and chromatin signals underlying transcription start-site selection

DEFF Research Database (Denmark)

Valen, Eivind; Sandelin, Albin Gustav

2011-01-01

A central question in cellular biology is how the cell regulates transcription and discerns when and where to initiate it. Locating transcription start sites (TSSs), the signals that specify them, and ultimately elucidating the mechanisms of regulated initiation has therefore been a recurrent theme....... In recent years substantial progress has been made towards this goal, spurred by the possibility of applying genome-wide, sequencing-based analysis. We now have a large collection of high-resolution datasets identifying locations of TSSs, protein-DNA interactions, and chromatin features over whole genomes...

Comparative transcriptional and genomic analysis of Plasmodium falciparum field isolates.

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Margaret J Mackinnon

2009-10-01

Full Text Available Mechanisms for differential regulation of gene expression may underlie much of the phenotypic variation and adaptability of malaria parasites. Here we describe transcriptional variation among culture-adapted field isolates of Plasmodium falciparum, the species responsible for most malarial disease. It was found that genes coding for parasite protein export into the red cell cytosol and onto its surface, and genes coding for sexual stage proteins involved in parasite transmission are up-regulated in field isolates compared with long-term laboratory isolates. Much of this variability was associated with the loss of small or large chromosomal segments, or other forms of gene copy number variation that are prevalent in the P. falciparum genome (copy number variants, CNVs. Expression levels of genes inside these segments were correlated to that of genes outside and adjacent to the segment boundaries, and this association declined with distance from the CNV boundary. This observation could not be explained by copy number variation in these adjacent genes. This suggests a local-acting regulatory role for CNVs in transcription of neighboring genes and helps explain the chromosomal clustering that we observed here. Transcriptional co-regulation of physical clusters of adaptive genes may provide a way for the parasite to readily adapt to its highly heterogeneous and strongly selective environment.

Genome-wide identification of direct HBx genomic targets

KAUST Repository

Guerrieri, Francesca

2017-02-17

Background The Hepatitis B Virus (HBV) HBx regulatory protein is required for HBV replication and involved in HBV-related carcinogenesis. HBx interacts with chromatin modifying enzymes and transcription factors to modulate histone post-translational modifications and to regulate viral cccDNA transcription and cellular gene expression. Aiming to identify genes and non-coding RNAs (ncRNAs) directly targeted by HBx, we performed a chromatin immunoprecipitation sequencing (ChIP-Seq) to analyse HBV recruitment on host cell chromatin in cells replicating HBV. Results ChIP-Seq high throughput sequencing of HBx-bound fragments was used to obtain a high-resolution, unbiased, mapping of HBx binding sites across the genome in HBV replicating cells. Protein-coding genes and ncRNAs involved in cell metabolism, chromatin dynamics and cancer were enriched among HBx targets together with genes/ncRNAs known to modulate HBV replication. The direct transcriptional activation of genes/miRNAs that potentiate endocytosis (Ras-related in brain (RAB) GTPase family) and autophagy (autophagy related (ATG) genes, beclin-1, miR-33a) and the transcriptional repression of microRNAs (miR-138, miR-224, miR-576, miR-596) that directly target the HBV pgRNA and would inhibit HBV replication, contribute to HBx-mediated increase of HBV replication. Conclusions Our ChIP-Seq analysis of HBx genome wide chromatin recruitment defined the repertoire of genes and ncRNAs directly targeted by HBx and led to the identification of new mechanisms by which HBx positively regulates cccDNA transcription and HBV replication.

Genome-wide DNA methylation patterns and transcription analysis in sheep muscle.

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Christine Couldrey

Full Text Available DNA methylation plays a central role in regulating many aspects of growth and development in mammals through regulating gene expression. The development of next generation sequencing technologies have paved the way for genome-wide, high resolution analysis of DNA methylation landscapes using methodology known as reduced representation bisulfite sequencing (RRBS. While RRBS has proven to be effective in understanding DNA methylation landscapes in humans, mice, and rats, to date, few studies have utilised this powerful method for investigating DNA methylation in agricultural animals. Here we describe the utilisation of RRBS to investigate DNA methylation in sheep Longissimus dorsi muscles. RRBS analysis of ∼1% of the genome from Longissimus dorsi muscles provided data of suitably high precision and accuracy for DNA methylation analysis, at all levels of resolution from genome-wide to individual nucleotides. Combining RRBS data with mRNAseq data allowed the sheep Longissimus dorsi muscle methylome to be compared with methylomes from other species. While some species differences were identified, many similarities were observed between DNA methylation patterns in sheep and other more commonly studied species. The RRBS data presented here highlights the complexity of epigenetic regulation of genes. However, the similarities observed across species are promising, in that knowledge gained from epigenetic studies in human and mice may be applied, with caution, to agricultural species. The ability to accurately measure DNA methylation in agricultural animals will contribute an additional layer of information to the genetic analyses currently being used to maximise production gains in these species.

Genome-wide expression profiling shows transcriptional reprogramming in Fusarium graminearum by Fusarium graminearum virus 1-DK21 infection

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Cho Won

2012-05-01

Full Text Available Abstract Background Fusarium graminearum virus 1 strain-DK21 (FgV1-DK21 is a mycovirus that confers hypovirulence to F. graminearum, which is the primary phytopathogenic fungus that causes Fusarium head blight (FHB disease in many cereals. Understanding the interaction between mycoviruses and plant pathogenic fungi is necessary for preventing damage caused by F. graminearum. Therefore, we investigated important cellular regulatory processes in a host containing FgV1-DK21 as compared to an uninfected parent using a transcriptional approach. Results Using a 3′-tiling microarray covering all known F. graminearum genes, we carried out genome-wide expression analyses of F. graminearum at two different time points. At the early point of growth of an infected strain as compared to an uninfected strain, genes associated with protein synthesis, including ribosome assembly, nucleolus, and ribosomal RNA processing, were significantly up-regulated. In addition, genes required for transcription and signal transduction, including fungal-specific transcription factors and cAMP signaling, respectively, were actively up-regulated. In contrast, genes involved in various metabolic pathways, particularly in producing carboxylic acids, aromatic amino acids, nitrogen compounds, and polyamines, showed dramatic down-regulation at the early time point. Moreover, genes associated with transport systems localizing to transmembranes were down-regulated at both time points. Conclusion This is the first report of global change in the prominent cellular pathways in the Fusarium host containing FgV1-DK21. The significant increase in transcripts for transcription and translation machinery in fungal host cells seems to be related to virus replication. In addition, significant down-regulation of genes required for metabolism and transporting systems in a fungal host containing the virus appears to be related to the host defense mechanism and fungal virulence. Taken together

Genome-wide identification of WRKY transcription factors in kiwifruit (Actinidia spp.) and analysis of WRKY expression in responses to biotic and abiotic stresses.

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Jing, Zhaobin; Liu, Zhande

2018-04-01

As one of the largest transcriptional factor families in plants, WRKY transcription factors play important roles in various biotic and abiotic stress responses. To date, WRKY genes in kiwifruit (Actinidia spp.) remain poorly understood. In our study, o total of 97 AcWRKY genes have been identified in the kiwifruit genome. An overview of these AcWRKY genes is analyzed, including the phylogenetic relationships, exon-intron structures, synteny and expression profiles. The 97 AcWRKY genes were divided into three groups based on the conserved WRKY domain. Synteny analysis indicated that segmental duplication events contributed to the expansion of the kiwifruit AcWRKY family. In addition, the synteny analysis between kiwifruit and Arabidopsis suggested that some of the AcWRKY genes were derived from common ancestors before the divergence of these two species. Conserved motifs outside the AcWRKY domain may reflect their functional conservation. Genome-wide segmental and tandem duplication were found, which may contribute to the expansion of AcWRKY genes. Furthermore, the analysis of selected AcWRKY genes showed a variety of expression patterns in five different organs as well as during biotic and abiotic stresses. The genome-wide identification and characterization of kiwifruit WRKY transcription factors provides insight into the evolutionary history and is a useful resource for further functional analyses of kiwifruit.

Genome-wide identification and comparative analysis of the heat shock transcription factor family in Chinese white pear (Pyrus bretschneideri) and five other Rosaceae species.

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Qiao, Xin; Li, Meng; Li, Leiting; Yin, Hao; Wu, Juyou; Zhang, Shaoling

2015-01-21

Heat shock transcription factors (Hsfs), which act as important transcriptional regulatory proteins in eukaryotes, play a central role in controlling the expression of heat-responsive genes. At present, the genomes of Chinese white pear ('Dangshansuli') and five other Rosaceae fruit crops have been fully sequenced. However, information about the Hsfs gene family in these Rosaceae species is limited, and the evolutionary history of the Hsfs gene family also remains unresolved. In this study, 137 Hsf genes were identified from six Rosaceae species (Pyrus bretschneideri, Malus × domestica, Prunus persica, Fragaria vesca, Prunus mume, and Pyrus communis), 29 of which came from Chinese white pear, designated as PbHsf. Based on the structural characteristics and phylogenetic analysis of these sequences, the Hsf family genes could be classified into three main groups (classes A, B, and C). Segmental and dispersed duplications were the primary forces underlying Hsf gene family expansion in the Rosaceae. Most of the PbHsf duplicated gene pairs were dated back to the recent whole-genome duplication (WGD, 30-45 million years ago (MYA)). Purifying selection also played a critical role in the evolution of Hsf genes. Transcriptome data demonstrated that the expression levels of the PbHsf genes were widely different. Six PbHsf genes were upregulated in fruit under naturally increased temperature. A comprehensive analysis of Hsf genes was performed in six Rosaceae species, and 137 full length Hsf genes were identified. The results presented here will undoubtedly be useful for better understanding the complexity of the Hsf gene family and will facilitate functional characterization in future studies.

Genome-wide identification and characterization of Notch transcription complex-binding sequence paired sites in leukemia cells

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Severson, Eric; Arnett, Kelly L.; Wang, Hongfang; Zang, Chongzhi; Taing, Len; Liu, Hudan; Pear, Warren S.; Liu, X. Shirley; Blacklow, Stephen C.; Aster, Jon C.

2018-01-01

Notch transcription complexes (NTCs) drive target gene expression by binding to two distinct types of genomic response elements, NTC monomer-binding sites and sequence-paired sites (SPSs) that bind NTC dimers. SPSs are conserved and are linked to the Notch-responsiveness of a few genes, but their overall contribution to Notch-dependent gene regulation is unknown. To address this issue, we determined the DNA sequence requirements for NTC dimerization using a fluorescence resonance energy transfer (FRET) assay, and applied insights from these in vitro studies to Notch-“addicted” leukemia cells. We find that SPSs contribute to the regulation of approximately a third of direct Notch target genes. While originally described in promoters, SPSs are present mainly in long-range enhancers, including an enhancer containing a newly described SPS that regulates HES5. Our work provides a general method for identifying sequence-paired sites in genome-wide data sets and highlights the widespread role of NTC dimerization in Notch-transformed leukemia cells. PMID:28465412

Introns Protect Eukaryotic Genomes from Transcription-Associated Genetic Instability.

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Bonnet, Amandine; Grosso, Ana R; Elkaoutari, Abdessamad; Coleno, Emeline; Presle, Adrien; Sridhara, Sreerama C; Janbon, Guilhem; Géli, Vincent; de Almeida, Sérgio F; Palancade, Benoit

2017-08-17

Transcription is a source of genetic instability that can notably result from the formation of genotoxic DNA:RNA hybrids, or R-loops, between the nascent mRNA and its template. Here we report an unexpected function for introns in counteracting R-loop accumulation in eukaryotic genomes. Deletion of endogenous introns increases R-loop formation, while insertion of an intron into an intronless gene suppresses R-loop accumulation and its deleterious impact on transcription and recombination in yeast. Recruitment of the spliceosome onto the mRNA, but not splicing per se, is shown to be critical to attenuate R-loop formation and transcription-associated genetic instability. Genome-wide analyses in a number of distant species differing in their intron content, including human, further revealed that intron-containing genes and the intron-richest genomes are best protected against R-loop accumulation and subsequent genetic instability. Our results thereby provide a possible rationale for the conservation of introns throughout the eukaryotic lineage. Copyright © 2017 Elsevier Inc. All rights reserved.

TFIIS-Dependent Non-coding Transcription Regulates Developmental Genome Rearrangements.

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Kamila Maliszewska-Olejniczak

2015-07-01

Full Text Available Because of their nuclear dimorphism, ciliates provide a unique opportunity to study the role of non-coding RNAs (ncRNAs in the communication between germline and somatic lineages. In these unicellular eukaryotes, a new somatic nucleus develops at each sexual cycle from a copy of the zygotic (germline nucleus, while the old somatic nucleus degenerates. In the ciliate Paramecium tetraurelia, the genome is massively rearranged during this process through the reproducible elimination of repeated sequences and the precise excision of over 45,000 short, single-copy Internal Eliminated Sequences (IESs. Different types of ncRNAs resulting from genome-wide transcription were shown to be involved in the epigenetic regulation of genome rearrangements. To understand how ncRNAs are produced from the entire genome, we have focused on a homolog of the TFIIS elongation factor, which regulates RNA polymerase II transcriptional pausing. Six TFIIS-paralogs, representing four distinct families, can be found in P. tetraurelia genome. Using RNA interference, we showed that TFIIS4, which encodes a development-specific TFIIS protein, is essential for the formation of a functional somatic genome. Molecular analyses and high-throughput DNA sequencing upon TFIIS4 RNAi demonstrated that TFIIS4 is involved in all kinds of genome rearrangements, including excision of ~48% of IESs. Localization of a GFP-TFIIS4 fusion revealed that TFIIS4 appears specifically in the new somatic nucleus at an early developmental stage, before IES excision. RT-PCR experiments showed that TFIIS4 is necessary for the synthesis of IES-containing non-coding transcripts. We propose that these IES+ transcripts originate from the developing somatic nucleus and serve as pairing substrates for germline-specific short RNAs that target elimination of their homologous sequences. Our study, therefore, connects the onset of zygotic non coding transcription to the control of genome plasticity in Paramecium

Genome-wide identification of soybean WRKY transcription factors in response to salt stress.

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Yu, Yanchong; Wang, Nan; Hu, Ruibo; Xiang, Fengning

2016-01-01

Members of the large family of WRKY transcription factors are involved in a wide range of developmental and physiological processes, most particularly in the plant response to biotic and abiotic stress. Here, an analysis of the soybean genome sequence allowed the identification of the full complement of 188 soybean WRKY genes. Phylogenetic analysis revealed that soybean WRKY genes were classified into three major groups (I, II, III), with the second group further categorized into five subgroups (IIa-IIe). The soybean WRKYs from each group shared similar gene structures and motif compositions. The location of the GmWRKYs was dispersed over all 20 soybean chromosomes. The whole genome duplication appeared to have contributed significantly to the expansion of the family. Expression analysis by RNA-seq indicated that in soybean root, 66 of the genes responded rapidly and transiently to the imposition of salt stress, all but one being up-regulated. While in aerial part, 49 GmWRKYs responded, all but two being down-regulated. RT-qPCR analysis showed that in the whole soybean plant, 66 GmWRKYs exhibited distinct expression patterns in response to salt stress, of which 12 showed no significant change, 35 were decreased, while 19 were induced. The data present here provide critical clues for further functional studies of WRKY gene in soybean salt tolerance.

Comprehensive genome-wide survey, genomic constitution and expression profiling of the NAC transcription factor family in foxtail millet (Setaria italica L..

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Swati Puranik

Full Text Available The NAC proteins represent a major plant-specific transcription factor family that has established enormously diverse roles in various plant processes. Aided by the availability of complete genomes, several members of this family have been identified in Arabidopsis, rice, soybean and poplar. However, no comprehensive investigation has been presented for the recently sequenced, naturally stress tolerant crop, Setaria italica (foxtail millet that is famed as a model crop for bioenergy research. In this study, we identified 147 putative NAC domain-encoding genes from foxtail millet by systematic sequence analysis and physically mapped them onto nine chromosomes. Genomic organization suggested that inter-chromosomal duplications may have been responsible for expansion of this gene family in foxtail millet. Phylogenetically, they were arranged into 11 distinct sub-families (I-XI, with duplicated genes fitting into one cluster and possessing conserved motif compositions. Comparative mapping with other grass species revealed some orthologous relationships and chromosomal rearrangements including duplication, inversion and deletion of genes. The evolutionary significance as duplication and divergence of NAC genes based on their amino acid substitution rates was understood. Expression profiling against various stresses and phytohormones provides novel insights into specific and/or overlapping expression patterns of SiNAC genes, which may be responsible for functional divergence among individual members in this crop. Further, we performed structure modeling and molecular simulation of a stress-responsive protein, SiNAC128, proffering an initial framework for understanding its molecular function. Taken together, this genome-wide identification and expression profiling unlocks new avenues for systematic functional analysis of novel NAC gene family candidates which may be applied for improvising stress adaption in plants.

Comprehensive genome-wide survey, genomic constitution and expression profiling of the NAC transcription factor family in foxtail millet (Setaria italica L.).

Science.gov (United States)

Puranik, Swati; Sahu, Pranav Pankaj; Mandal, Sambhu Nath; B, Venkata Suresh; Parida, Swarup Kumar; Prasad, Manoj

2013-01-01

The NAC proteins represent a major plant-specific transcription factor family that has established enormously diverse roles in various plant processes. Aided by the availability of complete genomes, several members of this family have been identified in Arabidopsis, rice, soybean and poplar. However, no comprehensive investigation has been presented for the recently sequenced, naturally stress tolerant crop, Setaria italica (foxtail millet) that is famed as a model crop for bioenergy research. In this study, we identified 147 putative NAC domain-encoding genes from foxtail millet by systematic sequence analysis and physically mapped them onto nine chromosomes. Genomic organization suggested that inter-chromosomal duplications may have been responsible for expansion of this gene family in foxtail millet. Phylogenetically, they were arranged into 11 distinct sub-families (I-XI), with duplicated genes fitting into one cluster and possessing conserved motif compositions. Comparative mapping with other grass species revealed some orthologous relationships and chromosomal rearrangements including duplication, inversion and deletion of genes. The evolutionary significance as duplication and divergence of NAC genes based on their amino acid substitution rates was understood. Expression profiling against various stresses and phytohormones provides novel insights into specific and/or overlapping expression patterns of SiNAC genes, which may be responsible for functional divergence among individual members in this crop. Further, we performed structure modeling and molecular simulation of a stress-responsive protein, SiNAC128, proffering an initial framework for understanding its molecular function. Taken together, this genome-wide identification and expression profiling unlocks new avenues for systematic functional analysis of novel NAC gene family candidates which may be applied for improvising stress adaption in plants.

Genome-wide identification and analysis of the B3 superfamily of transcription factors in Brassicaceae and major crop plants.

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Peng, Fred Y; Weselake, Randall J

2013-05-01

The plant-specific B3 superfamily of transcription factors has diverse functions in plant growth and development. Using a genome-wide domain analysis, we identified 92, 187, 58, 90, 81, 55, and 77 B3 transcription factor genes in the sequenced genome of Arabidopsis, Brassica rapa, castor bean (Ricinus communis), cocoa (Theobroma cacao), soybean (Glycine max), maize (Zea mays), and rice (Oryza sativa), respectively. The B3 superfamily has substantially expanded during the evolution in eudicots particularly in Brassicaceae, as compared to monocots in the analysis. We observed domain duplication in some of these B3 proteins, forming more complex domain architectures than currently understood. We found that the length of B3 domains exhibits a large variation, which may affect their exact number of α-helices and β-sheets in the core structure of B3 domains, and possibly have functional implications. Analysis of the public microarray data indicated that most of the B3 gene pairs encoding Arabidopsis-rice orthologs are preferentially expressed in different tissues, suggesting their different roles in these two species. Using ESTs in crops, we identified many B3 genes preferentially expressed in reproductive tissues. In a sequence-based quantitative trait loci analysis in rice and maize, we have found many B3 genes associated with traits such as grain yield, seed weight and number, and protein content. Our results provide a framework for future studies into the function of B3 genes in different phases of plant development, especially the ones related to traits in major crops.

Genome-wide mRNA processing in methanogenic archaea reveals post-transcriptional regulation of ribosomal protein synthesis.

Science.gov (United States)

Qi, Lei; Yue, Lei; Feng, Deqin; Qi, Fengxia; Li, Jie; Dong, Xiuzhu

2017-07-07

Unlike stable RNAs that require processing for maturation, prokaryotic cellular mRNAs generally follow an 'all-or-none' pattern. Herein, we used a 5΄ monophosphate transcript sequencing (5΄P-seq) that specifically captured the 5΄-end of processed transcripts and mapped the genome-wide RNA processing sites (PSSs) in a methanogenic archaeon. Following statistical analysis and stringent filtration, we identified 1429 PSSs, among which 23.5% and 5.4% were located in 5΄ untranslated region (uPSS) and intergenic region (iPSS), respectively. A predominant uridine downstream PSSs served as a processing signature. Remarkably, 5΄P-seq detected overrepresented uPSS and iPSS in the polycistronic operons encoding ribosomal proteins, and the majority upstream and proximal ribosome binding sites, suggesting a regulatory role of processing on translation initiation. The processed transcripts showed increased stability and translation efficiency. Particularly, processing within the tricistronic transcript of rplA-rplJ-rplL enhanced the translation of rplL, which can provide a driving force for the 1:4 stoichiometry of L10 to L12 in the ribosome. Growth-associated mRNA processing intensities were also correlated with the cellular ribosomal protein levels, thereby suggesting that mRNA processing is involved in tuning growth-dependent ribosome synthesis. In conclusion, our findings suggest that mRNA processing-mediated post-transcriptional regulation is a potential mechanism of ribosomal protein synthesis and stoichiometry. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Genome-Wide Comparative Gene Family Classification

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Frech, Christian; Chen, Nansheng

2010-01-01

Correct classification of genes into gene families is important for understanding gene function and evolution. Although gene families of many species have been resolved both computationally and experimentally with high accuracy, gene family classification in most newly sequenced genomes has not been done with the same high standard. This project has been designed to develop a strategy to effectively and accurately classify gene families across genomes. We first examine and compare the performance of computer programs developed for automated gene family classification. We demonstrate that some programs, including the hierarchical average-linkage clustering algorithm MC-UPGMA and the popular Markov clustering algorithm TRIBE-MCL, can reconstruct manual curation of gene families accurately. However, their performance is highly sensitive to parameter setting, i.e. different gene families require different program parameters for correct resolution. To circumvent the problem of parameterization, we have developed a comparative strategy for gene family classification. This strategy takes advantage of existing curated gene families of reference species to find suitable parameters for classifying genes in related genomes. To demonstrate the effectiveness of this novel strategy, we use TRIBE-MCL to classify chemosensory and ABC transporter gene families in C. elegans and its four sister species. We conclude that fully automated programs can establish biologically accurate gene families if parameterized accordingly. Comparative gene family classification finds optimal parameters automatically, thus allowing rapid insights into gene families of newly sequenced species. PMID:20976221

Genome-wide mapping of autonomous promoter activity in human cells.

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van Arensbergen, Joris; FitzPatrick, Vincent D; de Haas, Marcel; Pagie, Ludo; Sluimer, Jasper; Bussemaker, Harmen J; van Steensel, Bas

2017-02-01

Previous methods to systematically characterize sequence-intrinsic activity of promoters have been limited by relatively low throughput and the length of the sequences that could be tested. Here we present 'survey of regulatory elements' (SuRE), a method that assays more than 10 8 DNA fragments, each 0.2-2 kb in size, for their ability to drive transcription autonomously. In SuRE, a plasmid library of random genomic fragments upstream of a 20-bp barcode is constructed, and decoded by paired-end sequencing. This library is used to transfect cells, and barcodes in transcribed RNA are quantified by high-throughput sequencing. When applied to the human genome, we achieve 55-fold genome coverage, allowing us to map autonomous promoter activity genome-wide in K562 cells. By computational modeling we delineate subregions within promoters that are relevant for their activity. We show that antisense promoter transcription is generally dependent on the sense core promoter sequences, and that most enhancers and several families of repetitive elements act as autonomous transcription initiation sites.

Genome-Wide Classification and Evolutionary and Expression Analyses of Citrus MYB Transcription Factor Families in Sweet Orange

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Hou, Xiao-Jin; Li, Si-Bei; Liu, Sheng-Rui; Hu, Chun-Gen; Zhang, Jin-Zhi

2014-01-01

MYB family genes are widely distributed in plants and comprise one of the largest transcription factors involved in various developmental processes and defense responses of plants. To date, few MYB genes and little expression profiling have been reported for citrus. Here, we describe and classify 177 members of the sweet orange MYB gene (CsMYB) family in terms of their genomic gene structures and similarity to their putative Arabidopsis orthologs. According to these analyses, these CsMYBs were categorized into four groups (4R-MYB, 3R-MYB, 2R-MYB and 1R-MYB). Gene structure analysis revealed that 1R-MYB genes possess relatively more introns as compared with 2R-MYB genes. Investigation of their chromosomal localizations revealed that these CsMYBs are distributed across nine chromosomes. Sweet orange includes a relatively small number of MYB genes compared with the 198 members in Arabidopsis, presumably due to a paralog reduction related to repetitive sequence insertion into promoter and non-coding transcribed region of the genes. Comparative studies of CsMYBs and Arabidopsis showed that CsMYBs had fewer gene duplication events. Expression analysis revealed that the MYB gene family has a wide expression profile in sweet orange development and plays important roles in development and stress responses. In addition, 337 new putative microsatellites with flanking sequences sufficient for primer design were also identified from the 177 CsMYBs. These results provide a useful reference for the selection of candidate MYB genes for cloning and further functional analysis forcitrus. PMID:25375352

Genome-Wide Approaches to Drosophila Heart Development

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Manfred Frasch

2016-05-01

Full Text Available The development of the dorsal vessel in Drosophila is one of the first systems in which key mechanisms regulating cardiogenesis have been defined in great detail at the genetic and molecular level. Due to evolutionary conservation, these findings have also provided major inputs into studies of cardiogenesis in vertebrates. Many of the major components that control Drosophila cardiogenesis were discovered based on candidate gene approaches and their functions were defined by employing the outstanding genetic tools and molecular techniques available in this system. More recently, approaches have been taken that aim to interrogate the entire genome in order to identify novel components and describe genomic features that are pertinent to the regulation of heart development. Apart from classical forward genetic screens, the availability of the thoroughly annotated Drosophila genome sequence made new genome-wide approaches possible, which include the generation of massive numbers of RNA interference (RNAi reagents that were used in forward genetic screens, as well as studies of the transcriptomes and proteomes of the developing heart under normal and experimentally manipulated conditions. Moreover, genome-wide chromatin immunoprecipitation experiments have been performed with the aim to define the full set of genomic binding sites of the major cardiogenic transcription factors, their relevant target genes, and a more complete picture of the regulatory network that drives cardiogenesis. This review will give an overview on these genome-wide approaches to Drosophila heart development and on computational analyses of the obtained information that ultimately aim to provide a description of this process at the systems level.

Genome-wide analysis and expression profiling of the ERF transcription factor family in potato (Solanum tuberosum L.).

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Charfeddine, Mariam; Saïdi, Mohamed Najib; Charfeddine, Safa; Hammami, Asma; Gargouri Bouzid, Radhia

2015-04-01

The ERF transcription factors belong to the AP2/ERF superfamily, one of the largest transcription factor families in plants. They play important roles in plant development processes, as well as in the response to biotic, abiotic, and hormone signaling. In the present study, 155 putative ERF transcription factor genes were identified from the potato (Solanum tuberosum) genome database, and compared with those from Arabidopsis thaliana. The StERF proteins are divided into ten phylogenetic groups. Expression analyses of five StERFs were carried out by semi-quantitative RT-PCR and compared with published RNA-seq data. These latter analyses were used to distinguish tissue-specific, biotic, and abiotic stress genes as well as hormone-responsive StERF genes. The results are of interest to better understand the role of the AP2/ERF genes in response to diverse types of stress in potatoes. A comprehensive analysis of the physiological functions and biological roles of the ERF family genes in S. tuberosum is required to understand crop stress tolerance mechanisms.

Comparison of gene expression signatures of diamide, H2O2 and menadione exposed Aspergillus nidulans cultures – linking genome-wide transcriptional changes to cellular physiology

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Pócsi, István; Miskei, Márton; Karányi, Zsolt; Emri, Tamás; Ayoubi, Patricia; Pusztahelyi, Tünde; Balla, György; Prade, Rolf A

2005-01-01

Background In addition to their cytotoxic nature, reactive oxygen species (ROS) are also signal molecules in diverse cellular processes in eukaryotic organisms. Linking genome-wide transcriptional changes to cellular physiology in oxidative stress-exposed Aspergillus nidulans cultures provides the opportunity to estimate the sizes of peroxide (O22-), superoxide (O2•-) and glutathione/glutathione disulphide (GSH/GSSG) redox imbalance responses. Results Genome-wide transcriptional changes triggered by diamide, H2O2 and menadione in A. nidulans vegetative tissues were recorded using DNA microarrays containing 3533 unique PCR-amplified probes. Evaluation of LOESS-normalized data indicated that 2499 gene probes were affected by at least one stress-inducing agent. The stress induced by diamide and H2O2 were pulse-like, with recovery after 1 h exposure time while no recovery was observed with menadione. The distribution of stress-responsive gene probes among major physiological functional categories was approximately the same for each agent. The gene group sizes solely responsive to changes in intracellular O22-, O2•- concentrations or to GSH/GSSG redox imbalance were estimated at 7.7, 32.6 and 13.0 %, respectively. Gene groups responsive to diamide, H2O2 and menadione treatments and gene groups influenced by GSH/GSSG, O22- and O2•- were only partly overlapping with distinct enrichment profiles within functional categories. Changes in the GSH/GSSG redox state influenced expression of genes coding for PBS2 like MAPK kinase homologue, PSK2 kinase homologue, AtfA transcription factor, and many elements of ubiquitin tagging, cell division cycle regulators, translation machinery proteins, defense and stress proteins, transport proteins as well as many enzymes of the primary and secondary metabolisms. Meanwhile, a separate set of genes encoding transport proteins, CpcA and JlbA amino acid starvation-responsive transcription factors, and some elements of sexual development

GST-PRIME: an algorithm for genome-wide primer design.

Science.gov (United States)

Leister, Dario; Varotto, Claudio

2007-01-01

The profiling of mRNA expression based on DNA arrays has become a powerful tool to study genome-wide transcription of genes in a number of organisms. GST-PRIME is a software package created to facilitate large-scale primer design for the amplification of probes to be immobilized on arrays for transcriptome analyses, even though it can be also applied in low-throughput approaches. GST-PRIME allows highly efficient, direct amplification of gene-sequence tags (GSTs) from genomic DNA (gDNA), starting from annotated genome or transcript sequences. GST-PRIME provides a customer-friendly platform for automatic primer design, and despite the relative simplicity of the algorithm, experimental tests in the model plant species Arabidopsis thaliana confirmed the reliability of the software. This chapter describes the algorithm used for primer design, its input and output files, and the installation of the standalone package and its use.

DETECTION OF BACTERIAL SMALL TRANSCRIPTS FROM RNA-SEQ DATA: A COMPARATIVE ASSESSMENT.

Science.gov (United States)

Peña-Castillo, Lourdes; Grüell, Marc; Mulligan, Martin E; Lang, Andrew S

2016-01-01

Small non-coding RNAs (sRNAs) are regulatory RNA molecules that have been identified in a multitude of bacterial species and shown to control numerous cellular processes through various regulatory mechanisms. In the last decade, next generation RNA sequencing (RNA-seq) has been used for the genome-wide detection of bacterial sRNAs. Here we describe sRNA-Detect, a novel approach to identify expressed small transcripts from prokaryotic RNA-seq data. Using RNA-seq data from three bacterial species and two sequencing platforms, we performed a comparative assessment of five computational approaches for the detection of small transcripts. We demonstrate that sRNA-Detect improves upon current standalone computational approaches for identifying novel small transcripts in bacteria.

Genome-Wide Identification and Structural Analysis of bZIP Transcription Factor Genes in Brassica napus.

Science.gov (United States)

Zhou, Yan; Xu, Daixiang; Jia, Ledong; Huang, Xiaohu; Ma, Guoqiang; Wang, Shuxian; Zhu, Meichen; Zhang, Aoxiang; Guan, Mingwei; Lu, Kun; Xu, Xinfu; Wang, Rui; Li, Jiana; Qu, Cunmin

2017-10-24

The basic region/leucine zipper motif (bZIP) transcription factor family is one of the largest families of transcriptional regulators in plants. bZIP genes have been systematically characterized in some plants, but not in rapeseed ( Brassica napus ). In this study, we identified 247 BnbZIP genes in the rapeseed genome, which we classified into 10 subfamilies based on phylogenetic analysis of their deduced protein sequences. The BnbZIP genes were grouped into functional clades with Arabidopsis genes with similar putative functions, indicating functional conservation. Genome mapping analysis revealed that the BnbZIPs are distributed unevenly across all 19 chromosomes, and that some of these genes arose through whole-genome duplication and dispersed duplication events. All expression profiles of 247 bZIP genes were extracted from RNA-sequencing data obtained from 17 different B . napus ZS11 tissues with 42 various developmental stages. These genes exhibited different expression patterns in various tissues, revealing that these genes are differentially regulated. Our results provide a valuable foundation for functional dissection of the different BnbZIP homologs in B . napus and its parental lines and for molecular breeding studies of bZIP genes in B . napus .

StereoGene: rapid estimation of genome-wide correlation of continuous or interval feature data.

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Stavrovskaya, Elena D; Niranjan, Tejasvi; Fertig, Elana J; Wheelan, Sarah J; Favorov, Alexander V; Mironov, Andrey A

2017-10-15

Genomics features with similar genome-wide distributions are generally hypothesized to be functionally related, for example, colocalization of histones and transcription start sites indicate chromatin regulation of transcription factor activity. Therefore, statistical algorithms to perform spatial, genome-wide correlation among genomic features are required. Here, we propose a method, StereoGene, that rapidly estimates genome-wide correlation among pairs of genomic features. These features may represent high-throughput data mapped to reference genome or sets of genomic annotations in that reference genome. StereoGene enables correlation of continuous data directly, avoiding the data binarization and subsequent data loss. Correlations are computed among neighboring genomic positions using kernel correlation. Representing the correlation as a function of the genome position, StereoGene outputs the local correlation track as part of the analysis. StereoGene also accounts for confounders such as input DNA by partial correlation. We apply our method to numerous comparisons of ChIP-Seq datasets from the Human Epigenome Atlas and FANTOM CAGE to demonstrate its wide applicability. We observe the changes in the correlation between epigenomic features across developmental trajectories of several tissue types consistent with known biology and find a novel spatial correlation of CAGE clusters with donor splice sites and with poly(A) sites. These analyses provide examples for the broad applicability of StereoGene for regulatory genomics. The StereoGene C ++ source code, program documentation, Galaxy integration scripts and examples are available from the project homepage http://stereogene.bioinf.fbb.msu.ru/. favorov@sensi.org. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Comparative Genomic and Transcriptional Analyses of CRISPR Systems Across the Genus Pyrobaculum

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David L Bernick

2012-07-01

Full Text Available Within the domain Archaea, the CRISPR immune system appears to be nearly ubiquitous based on computational genome analyses. Initial studies in bacteria demonstrated that the CRISPR system targets invading plasmid and viral DNA. Recent experiments in the model archaeon Pyrococcus furiosus uncovered a novel RNA-targeting variant of the CRISPR system potentially unique to archaea. Because our understanding of CRISPR system evolution in other archaea is limited, we have taken a comparative genomic and transcriptomic view of the CRISPR arrays across six diverse species within the crenarchaeal genus Pyrobaculum. We present transcriptional data from each of four species in the genus (P. aerophilum, P. islandicum, P. calidifontis, P. arsenaticum, analyzing mature CRISPR-associated small RNA abundance from over 20 arrays. Within the genus, there is remarkable conservation of CRISPR array structure, as well as unique features that are have not been studied in other archaeal systems. These unique features include: a nearly invariant CRISPR promoter, conservation of direct repeat families, the 5' polarity of CRISPR-associated small RNA abundance, and a novel CRISPR-specific association with homologues of nurA and herA. These analyses provide a genus-level evolutionary perspective on archaeal CRISPR systems, broadening our understanding beyond existing non-comparative model systems.

Genome-wide organization and expression profiling of the NAC transcription factor family in potato (Solanum tuberosum L.).

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Singh, Anil Kumar; Sharma, Vishal; Pal, Awadhesh Kumar; Acharya, Vishal; Ahuja, Paramvir Singh

2013-08-01

NAC [no apical meristem (NAM), Arabidopsis thaliana transcription activation factor [ATAF1/2] and cup-shaped cotyledon (CUC2)] proteins belong to one of the largest plant-specific transcription factor (TF) families and play important roles in plant development processes, response to biotic and abiotic cues and hormone signalling. Our genome-wide analysis identified 110 StNAC genes in potato encoding for 136 proteins, including 14 membrane-bound TFs. The physical map positions of StNAC genes on 12 potato chromosomes were non-random, and 40 genes were found to be distributed in 16 clusters. The StNAC proteins were phylogenetically clustered into 12 subgroups. Phylogenetic analysis of StNACs along with their Arabidopsis and rice counterparts divided these proteins into 18 subgroups. Our comparative analysis has also identified 36 putative TNAC proteins, which appear to be restricted to Solanaceae family. In silico expression analysis, using Illumina RNA-seq transcriptome data, revealed tissue-specific, biotic, abiotic stress and hormone-responsive expression profile of StNAC genes. Several StNAC genes, including StNAC072 and StNAC101that are orthologs of known stress-responsive Arabidopsis RESPONSIVE TO DEHYDRATION 26 (RD26) were identified as highly abiotic stress responsive. Quantitative real-time polymerase chain reaction analysis largely corroborated the expression profile of StNAC genes as revealed by the RNA-seq data. Taken together, this analysis indicates towards putative functions of several StNAC TFs, which will provide blue-print for their functional characterization and utilization in potato improvement.

Genome-wide Analysis of RARβ Transcriptional Targets in Mouse Striatum Links Retinoic Acid Signaling with Huntington's Disease and Other Neurodegenerative Disorders.

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Niewiadomska-Cimicka, Anna; Krzyżosiak, Agnieszka; Ye, Tao; Podleśny-Drabiniok, Anna; Dembélé, Doulaye; Dollé, Pascal; Krężel, Wojciech

2017-07-01

Retinoic acid (RA) signaling through retinoic acid receptors (RARs), known for its multiple developmental functions, emerged more recently as an important regulator of adult brain physiology. How RAR-mediated regulation is achieved is poorly known, partly due to the paucity of information on critical target genes in the brain. Also, it is not clear how reduced RA signaling may contribute to pathophysiology of diverse neuropsychiatric disorders. We report the first genome-wide analysis of RAR transcriptional targets in the brain. Using chromatin immunoprecipitation followed by high-throughput sequencing and transcriptomic analysis of RARβ-null mutant mice, we identified genomic targets of RARβ in the striatum. Characterization of RARβ transcriptional targets in the mouse striatum points to mechanisms through which RAR may control brain functions and display neuroprotective activity. Namely, our data indicate with statistical significance (FDR 0.1) a strong contribution of RARβ in controlling neurotransmission, energy metabolism, and transcription, with a particular involvement of G-protein coupled receptor (p = 5.0e -5 ), cAMP (p = 4.5e -4 ), and calcium signaling (p = 3.4e -3 ). Many identified RARβ target genes related to these pathways have been implicated in Alzheimer's, Parkinson's, and Huntington's disease (HD), raising the possibility that compromised RA signaling in the striatum may be a mechanistic link explaining the similar affective and cognitive symptoms in these diseases. The RARβ transcriptional targets were particularly enriched for transcripts affected in HD. Using the R6/2 transgenic mouse model of HD, we show that partial sequestration of RARβ in huntingtin protein aggregates may account for reduced RA signaling reported in HD.

A Genome-wide Combinatorial Strategy Dissects Complex Genetic Architecture of Seed Coat Color in Chickpea.

Science.gov (United States)

Bajaj, Deepak; Das, Shouvik; Upadhyaya, Hari D; Ranjan, Rajeev; Badoni, Saurabh; Kumar, Vinod; Tripathi, Shailesh; Gowda, C L Laxmipathi; Sharma, Shivali; Singh, Sube; Tyagi, Akhilesh K; Parida, Swarup K

2015-01-01

The study identified 9045 high-quality SNPs employing both genome-wide GBS- and candidate gene-based SNP genotyping assays in 172, including 93 cultivated (desi and kabuli) and 79 wild chickpea accessions. The GWAS in a structured population of 93 sequenced accessions detected 15 major genomic loci exhibiting significant association with seed coat color. Five seed color-associated major genomic loci underlying robust QTLs mapped on a high-density intra-specific genetic linkage map were validated by QTL mapping. The integration of association and QTL mapping with gene haplotype-specific LD mapping and transcript profiling identified novel allelic variants (non-synonymous SNPs) and haplotypes in a MATE secondary transporter gene regulating light/yellow brown and beige seed coat color differentiation in chickpea. The down-regulation and decreased transcript expression of beige seed coat color-associated MATE gene haplotype was correlated with reduced proanthocyanidins accumulation in the mature seed coats of beige than light/yellow brown seed colored desi and kabuli accessions for their coloration/pigmentation. This seed color-regulating MATE gene revealed strong purifying selection pressure primarily in LB/YB seed colored desi and wild Cicer reticulatum accessions compared with the BE seed colored kabuli accessions. The functionally relevant molecular tags identified have potential to decipher the complex transcriptional regulatory gene function of seed coat coloration and for understanding the selective sweep-based seed color trait evolutionary pattern in cultivated and wild accessions during chickpea domestication. The genome-wide integrated approach employed will expedite marker-assisted genetic enhancement for developing cultivars with desirable seed coat color types in chickpea.

High-density transcriptional initiation signals underline genomic islands in bacteria.

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Qianli Huang

Full Text Available Genomic islands (GIs, frequently associated with the pathogenicity of bacteria and having a substantial influence on bacterial evolution, are groups of "alien" elements which probably undergo special temporal-spatial regulation in the host genome. Are there particular hallmark transcriptional signals for these "exotic" regions? We here explore the potential transcriptional signals that underline the GIs beyond the conventional views on basic sequence composition, such as codon usage and GC property bias. It showed that there is a significant enrichment of the transcription start positions (TSPs in the GI regions compared to the whole genome of Salmonella enterica and Escherichia coli. There was up to a four-fold increase for the 70% GIs, implying high-density TSPs profile can potentially differentiate the GI regions. Based on this feature, we developed a new sliding window method GIST, Genomic-island Identification by Signals of Transcription, to identify these regions. Subsequently, we compared the known GI-associated features of the GIs detected by GIST and by the existing method Islandviewer to those of the whole genome. Our method demonstrates high sensitivity in detecting GIs harboring genes with biased GI-like function, preferred subcellular localization, skewed GC property, shorter gene length and biased "non-optimal" codon usage. The special transcriptional signals discovered here may contribute to the coordinate expression regulation of foreign genes. Finally, by using GIST, we detected many interesting GIs in the 2011 German E. coli O104:H4 outbreak strain TY-2482, including the microcin H47 system and gene cluster ycgXEFZ-ymgABC that activates the production of biofilm matrix. The aforesaid findings highlight the power of GIST to predict GIs with distinct intrinsic features to the genome. The heterogeneity of cumulative TSPs profiles may not only be a better identity for "alien" regions, but also provide hints to the special

Nanobody®-based chromatin immunoprecipitation/micro-array analysis for genome-wide identification of transcription factor DNA binding sites

Science.gov (United States)

Nguyen-Duc, Trong; Peeters, Eveline; Muyldermans, Serge; Charlier, Daniel; Hassanzadeh-Ghassabeh, Gholamreza

2013-01-01

Nanobodies® are single-domain antibody fragments derived from camelid heavy-chain antibodies. Because of their small size, straightforward production in Escherichia coli, easy tailoring, high affinity, specificity, stability and solubility, nanobodies® have been exploited in various biotechnological applications. A major challenge in the post-genomics and post-proteomics era is the identification of regulatory networks involving nucleic acid–protein and protein–protein interactions. Here, we apply a nanobody® in chromatin immunoprecipitation followed by DNA microarray hybridization (ChIP-chip) for genome-wide identification of DNA–protein interactions. The Lrp-like regulator Ss-LrpB, arguably one of the best-studied specific transcription factors of the hyperthermophilic archaeon Sulfolobus solfataricus, was chosen for this proof-of-principle nanobody®-assisted ChIP. Three distinct Ss-LrpB-specific nanobodies®, each interacting with a different epitope, were generated for ChIP. Genome-wide ChIP-chip with one of these nanobodies® identified the well-established Ss-LrpB binding sites and revealed several unknown target sequences. Furthermore, these ChIP-chip profiles revealed auxiliary operator sites in the open reading frame of Ss-lrpB. Our work introduces nanobodies® as a novel class of affinity reagents for ChIP. Taking into account the unique characteristics of nanobodies®, in particular, their short generation time, nanobody®-based ChIP is expected to further streamline ChIP-chip and ChIP-Seq experiments, especially in organisms with no (or limited) possibility of genetic manipulation. PMID:23275538

Genome wide predictions of miRNA regulation by transcription factors.

Science.gov (United States)

Ruffalo, Matthew; Bar-Joseph, Ziv

2016-09-01

Reconstructing regulatory networks from expression and interaction data is a major goal of systems biology. While much work has focused on trying to experimentally and computationally determine the set of transcription-factors (TFs) and microRNAs (miRNAs) that regulate genes in these networks, relatively little work has focused on inferring the regulation of miRNAs by TFs. Such regulation can play an important role in several biological processes including development and disease. The main challenge for predicting such interactions is the very small positive training set currently available. Another challenge is the fact that a large fraction of miRNAs are encoded within genes making it hard to determine the specific way in which they are regulated. To enable genome wide predictions of TF-miRNA interactions, we extended semi-supervised machine-learning approaches to integrate a large set of different types of data including sequence, expression, ChIP-seq and epigenetic data. As we show, the methods we develop achieve good performance on both a labeled test set, and when analyzing general co-expression networks. We next analyze mRNA and miRNA cancer expression data, demonstrating the advantage of using the predicted set of interactions for identifying more coherent and relevant modules, genes, and miRNAs. The complete set of predictions is available on the supporting website and can be used by any method that combines miRNAs, genes, and TFs. Code and full set of predictions are available from the supporting website: http://cs.cmu.edu/~mruffalo/tf-mirna/ zivbj@cs.cmu.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Gene prediction and RFX transcriptional regulation analysis using comparative genomics

OpenAIRE

Chu, Jeffrey Shih Chieh

2011-01-01

Regulatory Factor X (RFX) is a family of transcription factors (TF) that is conserved in all metazoans, in some fungi, and in only a few single-cellular organisms. Seven members are found in mammals, nine in fishes, three in fruit flies, and a single member in nematodes and fungi. RFX is involved in many different roles in humans, but a particular function that is conserved in many metazoans is its regulation of ciliogenesis. Probing over 150 genomes for the presence of RFX and ciliary genes ...

Genome-wide Analysis of Gene Regulation

DEFF Research Database (Denmark)

Chen, Yun

to protein: through epigenetic modifications, transcription regulators or post-transcriptional controls. The following papers concern several layers of gene regulation with questions answered by different HTS approaches. Genome-wide screening of epigenetic changes by ChIP-seq allowed us to study both spatial...... and temporal alterations of histone modifications (Papers I and II). Coupling the data with machine learning approaches, we established a prediction framework to assess the most informative histone marks as well as their most influential nucleosome positions in predicting the promoter usages. (Papers I...... they regulated or if the sites had global elevated usage rates by multiple TFs. Using RNA-seq, 5’end-seq in combination with depletion of 5’exonuclease as well as nonsensemediated decay (NMD) factors, we systematically analyzed NMD substrates as well as their degradation intermediates in human cells (Paper V...

Comparative genomics and transcriptomics of trait-gene association

Directory of Open Access Journals (Sweden)

Pierlé Sebastián

2012-11-01

Full Text Available Abstract Background The Order Rickettsiales includes important tick-borne pathogens, from Rickettsia rickettsii, which causes Rocky Mountain spotted fever, to Anaplasma marginale, the most prevalent vector-borne pathogen of cattle. Although most pathogens in this Order are transmitted by arthropod vectors, little is known about the microbial determinants of transmission. A. marginale provides unique tools for studying the determinants of transmission, with multiple strain sequences available that display distinct and reproducible transmission phenotypes. The closed core A. marginale genome suggests that any phenotypic differences are due to single nucleotide polymorphisms (SNPs. We combined DNA/RNA comparative genomic approaches using strains with different tick transmission phenotypes and identified genes that segregate with transmissibility. Results Comparison of seven strains with different transmission phenotypes generated a list of SNPs affecting 18 genes and nine promoters. Transcriptional analysis found two candidate genes downstream from promoter SNPs that were differentially transcribed. To corroborate the comparative genomics approach we used three RNA-seq platforms to analyze the transcriptomes from two A. marginale strains with different transmission phenotypes. RNA-seq analysis confirmed the comparative genomics data and found 10 additional genes whose transcription between strains with distinct transmission efficiencies was significantly different. Six regions of the genome that contained no annotation were found to be transcriptionally active, and two of these newly identified transcripts were differentially transcribed. Conclusions This approach identified 30 genes and two novel transcripts potentially involved in tick transmission. We describe the transcriptome of an obligate intracellular bacterium in depth, while employing massive parallel sequencing to dissect an important trait in bacterial pathogenesis.

A Transcription Activator-Like Effector (TALE) Toolbox for Genome Engineering

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Sanjana, Neville E.; Cong, Le; Zhou, Yang; Cunniff, Margaret M.; Feng, Guoping; Zhang, Feng

2013-01-01

Transcription activator-like effectors (TALEs) are a class of naturally occurring DNA binding proteins found in the plant pathogen Xanthomonas sp. The DNA binding domain of each TALE consists of tandem 34-amino acid repeat modules that can be rearranged according to a simple cipher to target new DNA sequences. Customized TALEs can be used for a wide variety of genome engineering applications, including transcriptional modulation and genome editing. Here we describe a toolbox for rapid construction of custom TALE transcription factors (TALE-TFs) and nucleases (TALENs) using a hierarchical ligation procedure. This toolbox facilitates affordable and rapid construction of custom TALE-TFs and TALENs within one week and can be easily scaled up to construct TALEs for multiple targets in parallel. We also provide details for testing the activity in mammalian cells of custom TALE-TFs and TALENs using, respectively, qRT-PCR and Surveyor nuclease. The TALE toolbox described here will enable a broad range of biological applications. PMID:22222791

Comparative genomic characterization of three Streptococcus parauberis strains in fish pathogen, as assessed by wide-genome analyses.

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Seong-Won Nho

Full Text Available Streptococcus parauberis, which is the main causative agent of streptococcosis among olive flounder (Paralichthys olivaceus in northeast Asia, can be distinctly divided into two groups (type I and type II by an agglutination test. Here, the whole genome sequences of two Japanese strains (KRS-02083 and KRS-02109 were determined and compared with the previously determined genome of a Korean strain (KCTC 11537. The genomes of S. parauberis are intermediate in size and have lower GC contents than those of other streptococci. We annotated 2,236 and 2,048 genes in KRS-02083 and KRS-02109, respectively. Our results revealed that the three S. parauberis strains contain different genomic insertions and deletions. In particular, the genomes of Korean and Japanese strains encode different factors for sugar utilization; the former encodes the phosphotransferase system (PTS for sorbose, whereas the latter encodes proteins for lactose hydrolysis, respectively. And the KRS-02109 strain, specifically, was the type II strain found to be able to resist phage infection through the clustered regularly interspaced short palindromic repeats (CRISPR/Cas system and which might contribute valuably to serologically distribution. Thus, our genome-wide association study shows that polymorphisms can affect pathogen responses, providing insight into biological/biochemical pathways and phylogenetic diversity.

Genome-wide association study identifies five new schizophrenia loci.

LENUS (Irish Health Repository)

Ripke, Stephan

2011-10-01

We examined the role of common genetic variation in schizophrenia in a genome-wide association study of substantial size: a stage 1 discovery sample of 21,856 individuals of European ancestry and a stage 2 replication sample of 29,839 independent subjects. The combined stage 1 and 2 analysis yielded genome-wide significant associations with schizophrenia for seven loci, five of which are new (1p21.3, 2q32.3, 8p23.2, 8q21.3 and 10q24.32-q24.33) and two of which have been previously implicated (6p21.32-p22.1 and 18q21.2). The strongest new finding (P = 1.6 × 10(-11)) was with rs1625579 within an intron of a putative primary transcript for MIR137 (microRNA 137), a known regulator of neuronal development. Four other schizophrenia loci achieving genome-wide significance contain predicted targets of MIR137, suggesting MIR137-mediated dysregulation as a previously unknown etiologic mechanism in schizophrenia. In a joint analysis with a bipolar disorder sample (16,374 affected individuals and 14,044 controls), three loci reached genome-wide significance: CACNA1C (rs4765905, P = 7.0 × 10(-9)), ANK3 (rs10994359, P = 2.5 × 10(-8)) and the ITIH3-ITIH4 region (rs2239547, P = 7.8 × 10(-9)).

Genome-wide mapping of transcription start sites yields novel insights into the primary transcriptome of Pseudomonas putida

DEFF Research Database (Denmark)

D'Arrigo, Isotta; Bojanovic, Klara; Yang, Xiaochen

2016-01-01

was examined using an in vivo assay with GFP-fusion vectors and shown to function via a translational repression mechanism. Furthermore, 56 novel intergenic small RNAs and 8 putative actuaton transcripts were detected, as well as 8 novel open reading frames (ORFs). This study illustrates how global mapping...... of TSSs can yield novel insights into the transcriptional features and RNA output of bacterial genomes....

Genome-wide DNA binding pattern of the homeodomain transcription factor Sine oculis (So in the developing eye of Drosophila melanogaster

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Barbara Jusiak

2014-12-01

Full Text Available The eye of the fruit fly Drosophila melanogaster provides a highly tractable genetic model system for the study of animal development, and many genes that regulate Drosophila eye formation have homologs implicated in human development and disease. Among these is the homeobox gene sine oculis (so, which encodes a homeodomain transcription factor (TF that is both necessary for eye development and sufficient to reprogram a subset of cells outside the normal eye field toward an eye fate. We have performed a genome-wide analysis of So binding to DNA prepared from developing Drosophila eye tissue in order to identify candidate direct targets of So-mediated transcriptional regulation, as described in our recent article [20]. The data are available from NCBI Gene Expression Omnibus (GEO with the accession number GSE52943. Here we describe the methods, data analysis, and quality control of our So ChIP-seq dataset.

Transcription as a Threat to Genome Integrity.

Science.gov (United States)

Gaillard, Hélène; Aguilera, Andrés

2016-06-02

Genomes undergo different types of sporadic alterations, including DNA damage, point mutations, and genome rearrangements, that constitute the basis for evolution. However, these changes may occur at high levels as a result of cell pathology and trigger genome instability, a hallmark of cancer and a number of genetic diseases. In the last two decades, evidence has accumulated that transcription constitutes an important natural source of DNA metabolic errors that can compromise the integrity of the genome. Transcription can create the conditions for high levels of mutations and recombination by its ability to open the DNA structure and remodel chromatin, making it more accessible to DNA insulting agents, and by its ability to become a barrier to DNA replication. Here we review the molecular basis of such events from a mechanistic perspective with particular emphasis on the role of transcription as a genome instability determinant.

Genome-wide expressions in autologous eutopic and ectopic endometrium of fertile women with endometriosis

OpenAIRE

Khan, Meraj A; Sengupta, Jayasree; Mittal, Suneeta; Ghosh, Debabrata

2012-01-01

Abstract Background In order to obtain a lead of the pathophysiology of endometriosis, genome-wide expressional analyses of eutopic and ectopic endometrium have earlier been reported, however, the effects of stages of severity and phases of menstrual cycle on expressional profiles have not been examined. The effect of genetic heterogeneity and fertility history on transcriptional activity was also not considered. In the present study, a genome-wide expression analysis of autologous, paired eu...

Genome-wide organization and expression profiling of the R2R3-MYB transcription factor family in pineapple (Ananas comosus).

Science.gov (United States)

Liu, Chaoyang; Xie, Tao; Chen, Chenjie; Luan, Aiping; Long, Jianmei; Li, Chuhao; Ding, Yaqi; He, Yehua

2017-07-01

The MYB proteins comprise one of the largest families of plant transcription factors, which are involved in various plant physiological and biochemical processes. Pineapple (Ananas comosus) is one of three most important tropical fruits worldwide. The completion of pineapple genome sequencing provides a great opportunity to investigate the organization and evolutionary traits of pineapple MYB genes at the genome-wide level. In the present study, a total of 94 pineapple R2R3-MYB genes were identified and further phylogenetically classified into 26 subfamilies, as supported by the conserved gene structures and motif composition. Collinearity analysis indicated that the segmental duplication events played a crucial role in the expansion of pineapple MYB gene family. Further comparative phylogenetic analysis suggested that there have been functional divergences of MYB gene family during plant evolution. RNA-seq data from different tissues and developmental stages revealed distinct temporal and spatial expression profiles of the AcMYB genes. Further quantitative expression analysis showed the specific expression patterns of the selected putative stress-related AcMYB genes in response to distinct abiotic stress and hormonal treatments. The comprehensive expression analysis of the pineapple MYB genes, especially the tissue-preferential and stress-responsive genes, could provide valuable clues for further function characterization. In this work, we systematically identified AcMYB genes by analyzing the pineapple genome sequence using a set of bioinformatics approaches. Our findings provide a global insight into the organization, phylogeny and expression patterns of the pineapple R2R3-MYB genes, and hence contribute to the greater understanding of their biological roles in pineapple.

Genome-wide distribution comparative and composition analysis of the SSRs in Poaceae.

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Wang, Yi; Yang, Chao; Jin, Qiaojun; Zhou, Dongjie; Wang, Shuangshuang; Yu, Yuanjie; Yang, Long

2015-02-15

The Poaceae family is of great importance to human beings since it comprises the cereal grasses which are the main sources for human food and animal feed. With the rapid growth of genomic data from Poaceae members, comparative genomics becomes a convinent method to study genetics of diffierent species. The SSRs (Simple Sequence Repeats) are widely used markers in the studies of Poaceae for their high abundance and stability. In this study, using the genomic sequences of 9 Poaceae species, we detected 11,993,943 SSR loci and developed 6,799,910 SSR primer pairs. The results show that SSRs are distributed on all the genomic elements in grass. Hexamer is the most frequent motif and AT/TA is the most frequent motif in dimer. The abundance of the SSRs has a positive linear relationship with the recombination rate. SSR sequences in the coding regions involve a higher GC content in the Poaceae than that in the other species. SSRs of 70-80 bp in length showed the highest AT/GC base ratio among all of these loci. The result shows the highest polymorphism rate belongs to the SSRs ranged from 30 bp to 40 bp. Using all the SSR primers of Japonica, nineteen universal primers were selected and located on the genome of the grass family. The information of SSR loci, the SSR primers and the tools of mining and analyzing SSR are provided in the PSSRD (Poaceae SSR Database, http://biodb.sdau.edu.cn/pssrd/). Our study and the PSSRD database provide a foundation for the comparative study in the Poaceae and it will accelerate the study on markers application, gene mapping and molecular breeding.

From human monocytes to genome-wide binding sites--a protocol for small amounts of blood: monocyte isolation/ChIP-protocol/library amplification/genome wide computational data analysis.

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Sebastian Weiterer

Full Text Available Chromatin immunoprecipitation in combination with a genome-wide analysis via high-throughput sequencing is the state of the art method to gain genome-wide representation of histone modification or transcription factor binding profiles. However, chromatin immunoprecipitation analysis in the context of human experimental samples is limited, especially in the case of blood cells. The typically extremely low yields of precipitated DNA are usually not compatible with library amplification for next generation sequencing. We developed a highly reproducible protocol to present a guideline from the first step of isolating monocytes from a blood sample to analyse the distribution of histone modifications in a genome-wide manner.The protocol describes the whole work flow from isolating monocytes from human blood samples followed by a high-sensitivity and small-scale chromatin immunoprecipitation assay with guidance for generating libraries compatible with next generation sequencing from small amounts of immunoprecipitated DNA.

Mammalian RNA polymerase II core promoters: insights from genome-wide studies

DEFF Research Database (Denmark)

Sandelin, Albin; Carninci, Piero; Lenhard, Boris

2007-01-01

The identification and characterization of mammalian core promoters and transcription start sites is a prerequisite to understanding how RNA polymerase II transcription is controlled. New experimental technologies have enabled genome-wide discovery and characterization of core promoters, revealing...... in the mammalian transcriptome and proteome. Promoters can be described by their start site usage distribution, which is coupled to the occurrence of cis-regulatory elements, gene function and evolutionary constraints. A comprehensive survey of mammalian promoters is a major step towards describing...

Genome-wide analysis of WRKY transcription factors in white pear (Pyrus bretschneideri) reveals evolution and patterns under drought stress.

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Huang, Xiaosan; Li, Kongqing; Xu, Xiaoyong; Yao, Zhenghong; Jin, Cong; Zhang, Shaoling

2015-12-24

WRKY transcription factors (TFs) constitute one of the largest protein families in higher plants, and its members contain one or two conserved WRKY domains, about 60 amino acid residues with the WRKYGQK sequence followed by a C2H2 or C2HC zinc finger motif. WRKY proteins play significant roles in plant development, and in responses to biotic and abiotic stresses. Pear (Pyrus bretschneideri) is one of the most important fruit crops in the world and is frequently threatened by abiotic stress, such as drought, affecting growth, development and productivity. Although the pear genome sequence has been released, little is known about the WRKY TFs in pear, especially in respond to drought stress at the genome-wide level. We identified a total of 103 WRKY TFs in the pear genome. Based on the structural features of WRKY proteins and topology of the phylogenetic tree, the pear WRKY (PbWRKY) family was classified into seven groups (Groups 1, 2a-e, and 3). The microsyteny analysis indicated that 33 (32%) PbWRKY genes were tandemly duplicated and 57 genes (55.3%) were segmentally duplicated. RNA-seq experiment data and quantitative real-time reverse transcription PCR revealed that PbWRKY genes in different groups were induced by drought stress, and Group 2a and 3 were mainly involved in the biological pathways in response to drought stress. Furthermore, adaptive evolution analysis detected a significant positive selection for Pbr001425 in Group 3, and its expression pattern differed from that of other members in this group. The present study provides a solid foundation for further functional dissection and molecular evolution of WRKY TFs in pear, especially for improving the water-deficient resistance of pear through manipulation of the PbWRKYs.

Genome-wide RNA polymerase II profiles and RNA accumulation reveal kinetics of transcription and associated epigenetic changes during diurnal cycles.

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Gwendal Le Martelot

Full Text Available Interactions of cell-autonomous circadian oscillators with diurnal cycles govern the temporal compartmentalization of cell physiology in mammals. To understand the transcriptional and epigenetic basis of diurnal rhythms in mouse liver genome-wide, we generated temporal DNA occupancy profiles by RNA polymerase II (Pol II as well as profiles of the histone modifications H3K4me3 and H3K36me3. We used these data to quantify the relationships of phases and amplitudes between different marks. We found that rhythmic Pol II recruitment at promoters rather than rhythmic transition from paused to productive elongation underlies diurnal gene transcription, a conclusion further supported by modeling. Moreover, Pol II occupancy preceded mRNA accumulation by 3 hours, consistent with mRNA half-lives. Both methylation marks showed that the epigenetic landscape is highly dynamic and globally remodeled during the 24-hour cycle. While promoters of transcribed genes had tri-methylated H3K4 even at their trough activity times, tri-methylation levels reached their peak, on average, 1 hour after Pol II. Meanwhile, rhythms in tri-methylation of H3K36 lagged transcription by 3 hours. Finally, modeling profiles of Pol II occupancy and mRNA accumulation identified three classes of genes: one showing rhythmicity both in transcriptional and mRNA accumulation, a second class with rhythmic transcription but flat mRNA levels, and a third with constant transcription but rhythmic mRNAs. The latter class emphasizes widespread temporally gated posttranscriptional regulation in the mouse liver.

Cloud computing for comparative genomics.

Science.gov (United States)

Wall, Dennis P; Kudtarkar, Parul; Fusaro, Vincent A; Pivovarov, Rimma; Patil, Prasad; Tonellato, Peter J

2010-05-18

Large comparative genomics studies and tools are becoming increasingly more compute-expensive as the number of available genome sequences continues to rise. The capacity and cost of local computing infrastructures are likely to become prohibitive with the increase, especially as the breadth of questions continues to rise. Alternative computing architectures, in particular cloud computing environments, may help alleviate this increasing pressure and enable fast, large-scale, and cost-effective comparative genomics strategies going forward. To test this, we redesigned a typical comparative genomics algorithm, the reciprocal smallest distance algorithm (RSD), to run within Amazon's Elastic Computing Cloud (EC2). We then employed the RSD-cloud for ortholog calculations across a wide selection of fully sequenced genomes. We ran more than 300,000 RSD-cloud processes within the EC2. These jobs were farmed simultaneously to 100 high capacity compute nodes using the Amazon Web Service Elastic Map Reduce and included a wide mix of large and small genomes. The total computation time took just under 70 hours and cost a total of $6,302 USD. The effort to transform existing comparative genomics algorithms from local compute infrastructures is not trivial. However, the speed and flexibility of cloud computing environments provides a substantial boost with manageable cost. The procedure designed to transform the RSD algorithm into a cloud-ready application is readily adaptable to similar comparative genomics problems.

Genome wide characterization of simple sequence repeats in watermelon genome and their application in comparative mapping and genetic diversity analysis.

Science.gov (United States)

Zhu, Huayu; Song, Pengyao; Koo, Dal-Hoe; Guo, Luqin; Li, Yanman; Sun, Shouru; Weng, Yiqun; Yang, Luming

2016-08-05

Microsatellite markers are one of the most informative and versatile DNA-based markers used in plant genetic research, but their development has traditionally been difficult and costly. The whole genome sequencing with next-generation sequencing (NGS) technologies provides large amounts of sequence data to develop numerous microsatellite markers at whole genome scale. SSR markers have great advantage in cross-species comparisons and allow investigation of karyotype and genome evolution through highly efficient computation approaches such as in silico PCR. Here we described genome wide development and characterization of SSR markers in the watermelon (Citrullus lanatus) genome, which were then use in comparative analysis with two other important crop species in the Cucurbitaceae family: cucumber (Cucumis sativus L.) and melon (Cucumis melo L.). We further applied these markers in evaluating the genetic diversity and population structure in watermelon germplasm collections. A total of 39,523 microsatellite loci were identified from the watermelon draft genome with an overall density of 111 SSRs/Mbp, and 32,869 SSR primers were designed with suitable flanking sequences. The dinucleotide SSRs were the most common type representing 34.09 % of the total SSR loci and the AT-rich motifs were the most abundant in all nucleotide repeat types. In silico PCR analysis identified 832 and 925 SSR markers with each having a single amplicon in the cucumber and melon draft genome, respectively. Comparative analysis with these cross-species SSR markers revealed complicated mosaic patterns of syntenic blocks among the genomes of three species. In addition, genetic diversity analysis of 134 watermelon accessions with 32 highly informative SSR loci placed these lines into two groups with all accessions of C.lanatus var. citorides and three accessions of C. colocynthis clustered in one group and all accessions of C. lanatus var. lanatus and the remaining accessions of C. colocynthis

Transcriptional and chromatin regulation during fasting – The genomic era

Science.gov (United States)

Goldstein, Ido; Hager, Gordon L.

2015-01-01

An elaborate metabolic response to fasting is orchestrated by the liver and is heavily reliant upon transcriptional regulation. In response to hormones (glucagon, glucocorticoids) many transcription factors (TFs) are activated and regulate various genes involved in metabolic pathways aimed at restoring homeostasis: gluconeogenesis, fatty acid oxidation, ketogenesis and amino acid shuttling. We summarize the recent discoveries regarding fasting-related TFs with an emphasis on genome-wide binding patterns. Collectively, the summarized findings reveal a large degree of co-operation between TFs during fasting which occurs at motif-rich DNA sites bound by a combination of TFs. These new findings implicate transcriptional and chromatin regulation as major determinants of the response to fasting and unravels the complex, multi-TF nature of this response. PMID:26520657

Genome-wide expression profiling of complex regional pain syndrome.

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Eun-Heui Jin

Full Text Available Complex regional pain syndrome (CRPS is a chronic, progressive, and devastating pain syndrome characterized by spontaneous pain, hyperalgesia, allodynia, altered skin temperature, and motor dysfunction. Although previous gene expression profiling studies have been conducted in animal pain models, there genome-wide expression profiling in the whole blood of CRPS patients has not been reported yet. Here, we successfully identified certain pain-related genes through genome-wide expression profiling in the blood from CRPS patients. We found that 80 genes were differentially expressed between 4 CRPS patients (2 CRPS I and 2 CRPS II and 5 controls (cut-off value: 1.5-fold change and p<0.05. Most of those genes were associated with signal transduction, developmental processes, cell structure and motility, and immunity and defense. The expression levels of major histocompatibility complex class I A subtype (HLA-A29.1, matrix metalloproteinase 9 (MMP9, alanine aminopeptidase N (ANPEP, l-histidine decarboxylase (HDC, granulocyte colony-stimulating factor 3 receptor (G-CSF3R, and signal transducer and activator of transcription 3 (STAT3 genes selected from the microarray were confirmed in 24 CRPS patients and 18 controls by quantitative reverse transcription-polymerase chain reaction (qRT-PCR. We focused on the MMP9 gene that, by qRT-PCR, showed a statistically significant difference in expression in CRPS patients compared to controls with the highest relative fold change (4.0±1.23 times and p = 1.4×10(-4. The up-regulation of MMP9 gene in the blood may be related to the pain progression in CRPS patients. Our findings, which offer a valuable contribution to the understanding of the differential gene expression in CRPS may help in the understanding of the pathophysiology of CRPS pain progression.

Ensembl Genomes 2013: scaling up access to genome-wide data.

Science.gov (United States)

Kersey, Paul Julian; Allen, James E; Christensen, Mikkel; Davis, Paul; Falin, Lee J; Grabmueller, Christoph; Hughes, Daniel Seth Toney; Humphrey, Jay; Kerhornou, Arnaud; Khobova, Julia; Langridge, Nicholas; McDowall, Mark D; Maheswari, Uma; Maslen, Gareth; Nuhn, Michael; Ong, Chuang Kee; Paulini, Michael; Pedro, Helder; Toneva, Iliana; Tuli, Mary Ann; Walts, Brandon; Williams, Gareth; Wilson, Derek; Youens-Clark, Ken; Monaco, Marcela K; Stein, Joshua; Wei, Xuehong; Ware, Doreen; Bolser, Daniel M; Howe, Kevin Lee; Kulesha, Eugene; Lawson, Daniel; Staines, Daniel Michael

2014-01-01

Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species. The project exploits and extends technologies for genome annotation, analysis and dissemination, developed in the context of the vertebrate-focused Ensembl project, and provides a complementary set of resources for non-vertebrate species through a consistent set of programmatic and interactive interfaces. These provide access to data including reference sequence, gene models, transcriptional data, polymorphisms and comparative analysis. This article provides an update to the previous publications about the resource, with a focus on recent developments. These include the addition of important new genomes (and related data sets) including crop plants, vectors of human disease and eukaryotic pathogens. In addition, the resource has scaled up its representation of bacterial genomes, and now includes the genomes of over 9000 bacteria. Specific extensions to the web and programmatic interfaces have been developed to support users in navigating these large data sets. Looking forward, analytic tools to allow targeted selection of data for visualization and download are likely to become increasingly important in future as the number of available genomes increases within all domains of life, and some of the challenges faced in representing bacterial data are likely to become commonplace for eukaryotes in future.

Genome-wide transcriptional profiling of skin and dorsal root ganglia after ultraviolet-B-induced inflammation.

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John M Dawes

Full Text Available Ultraviolet-B (UVB-induced inflammation produces a dose-dependent mechanical and thermal hyperalgesia in both humans and rats, most likely via inflammatory mediators acting at the site of injury. Previous work has shown that the gene expression of cytokines and chemokines is positively correlated between species and that these factors can contribute to UVB-induced pain. In order to investigate other potential pain mediators in this model we used RNA-seq to perform genome-wide transcriptional profiling in both human and rat skin at the peak of hyperalgesia. In addition we have also measured transcriptional changes in the L4 and L5 DRG of the rat model. Our data show that UVB irradiation produces a large number of transcriptional changes in the skin: 2186 and 3888 genes are significantly dysregulated in human and rat skin, respectively. The most highly up-regulated genes in human skin feature those encoding cytokines (IL6 and IL24, chemokines (CCL3, CCL20, CXCL1, CXCL2, CXCL3 and CXCL5, the prostanoid synthesising enzyme COX-2 and members of the keratin gene family. Overall there was a strong positive and significant correlation in gene expression between the human and rat (R = 0.8022. In contrast to the skin, only 39 genes were significantly dysregulated in the rat L4 and L5 DRGs, the majority of which had small fold change values. Amongst the most up-regulated genes in DRG were REG3B, CCL2 and VGF. Overall, our data shows that numerous genes were up-regulated in UVB irradiated skin at the peak of hyperalgesia in both human and rats. Many of the top up-regulated genes were cytokines and chemokines, highlighting again their potential as pain mediators. However many other genes were also up-regulated and might play a role in UVB-induced hyperalgesia. In addition, the strong gene expression correlation between species re-emphasises the value of the UVB model as translational tool to study inflammatory pain.

Cloud computing for comparative genomics

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Pivovarov Rimma

2010-05-01

Full Text Available Abstract Background Large comparative genomics studies and tools are becoming increasingly more compute-expensive as the number of available genome sequences continues to rise. The capacity and cost of local computing infrastructures are likely to become prohibitive with the increase, especially as the breadth of questions continues to rise. Alternative computing architectures, in particular cloud computing environments, may help alleviate this increasing pressure and enable fast, large-scale, and cost-effective comparative genomics strategies going forward. To test this, we redesigned a typical comparative genomics algorithm, the reciprocal smallest distance algorithm (RSD, to run within Amazon's Elastic Computing Cloud (EC2. We then employed the RSD-cloud for ortholog calculations across a wide selection of fully sequenced genomes. Results We ran more than 300,000 RSD-cloud processes within the EC2. These jobs were farmed simultaneously to 100 high capacity compute nodes using the Amazon Web Service Elastic Map Reduce and included a wide mix of large and small genomes. The total computation time took just under 70 hours and cost a total of $6,302 USD. Conclusions The effort to transform existing comparative genomics algorithms from local compute infrastructures is not trivial. However, the speed and flexibility of cloud computing environments provides a substantial boost with manageable cost. The procedure designed to transform the RSD algorithm into a cloud-ready application is readily adaptable to similar comparative genomics problems.

Genome-wide analysis of transcription factors during somatic embryogenesis in banana (Musa spp.) cv. Grand Naine.

Science.gov (United States)

Shivani; Awasthi, Praveen; Sharma, Vikrant; Kaur, Navjot; Kaur, Navneet; Pandey, Pankaj; Tiwari, Siddharth

2017-01-01

Transcription factors BABY BOOM (BBM), WUSCHEL (WUS), BSD, LEAFY COTYLEDON (LEC), LEAFY COTYLEDON LIKE (LIL), VIVIPAROUS1 (VP1), CUP SHAPED COTYLEDONS (CUC), BOLITA (BOL), and AGAMOUS LIKE (AGL) play a crucial role in somatic embryogenesis. In this study, we identified eighteen genes of these nine transcription factors families from the banana genome database. All genes were analyzed for their structural features, subcellular, and chromosomal localization. Protein sequence analysis indicated the presence of characteristic conserved domains in these transcription factors. Phylogenetic analysis revealed close evolutionary relationship among most transcription factors of various monocots. The expression patterns of eighteen genes in embryogenic callus containing somatic embryos (precisely isolated by Laser Capture Microdissection), non-embryogenic callus, and cell suspension cultures of banana cultivar Grand Naine were analyzed. The application of 2, 4-dichlorophenoxyacetic acid (2, 4-D) in the callus induction medium enhanced the expression of MaBBM1, MaBBM2, MaWUS2, and MaVP1 in the embryogenic callus. It suggested 2, 4-D acts as an inducer for the expression of these genes. The higher expression of MaBBM2 and MaWUS2 in embryogenic cell suspension (ECS) as compared to non-embryogenic cells suspension (NECS), suggested that these genes may play a crucial role in banana somatic embryogenesis. MaVP1 showed higher expression in both ECS and NECS, whereas MaLEC2 expression was significantly higher in NECS. It suggests that MaLEC2 has a role in the development of non-embryogenic cells. We postulate that MaBBM2 and MaWUS2 can be served as promising molecular markers for the embryogencity in banana.

Genome-wide analysis identifies chickpea (Cicer arietinum) heat stress transcription factors (Hsfs) responsive to heat stress at the pod development stage.

Science.gov (United States)

Chidambaranathan, Parameswaran; Jagannadham, Prasanth Tej Kumar; Satheesh, Viswanathan; Kohli, Deshika; Basavarajappa, Santosh Halasabala; Chellapilla, Bharadwaj; Kumar, Jitendra; Jain, Pradeep Kumar; Srinivasan, R

2018-05-01

The heat stress transcription factors (Hsfs) play a prominent role in thermotolerance and eliciting the heat stress response in plants. Identification and expression analysis of Hsfs gene family members in chickpea would provide valuable information on heat stress responsive Hsfs. A genome-wide analysis of Hsfs gene family resulted in the identification of 22 Hsf genes in chickpea in both desi and kabuli genome. Phylogenetic analysis distinctly separated 12 A, 9 B, and 1 C class Hsfs, respectively. An analysis of cis-regulatory elements in the upstream region of the genes identified many stress responsive elements such as heat stress elements (HSE), abscisic acid responsive element (ABRE) etc. In silico expression analysis showed nine and three Hsfs were also expressed in drought and salinity stresses, respectively. Q-PCR expression analysis of Hsfs under heat stress at pod development and at 15 days old seedling stage showed that CarHsfA2, A6, and B2 were significantly upregulated in both the stages of crop growth and other four Hsfs (CarHsfA2, A6a, A6c, B2a) showed early transcriptional upregulation for heat stress at seedling stage of chickpea. These subclasses of Hsfs identified in this study can be further evaluated as candidate genes in the characterization of heat stress response in chickpea.

Genome-Wide Expression Profiling of Complex Regional Pain Syndrome

Science.gov (United States)

Jin, Eun-Heui; Zhang, Enji; Ko, Youngkwon; Sim, Woo Seog; Moon, Dong Eon; Yoon, Keon Jung; Hong, Jang Hee; Lee, Won Hyung

2013-01-01

Complex regional pain syndrome (CRPS) is a chronic, progressive, and devastating pain syndrome characterized by spontaneous pain, hyperalgesia, allodynia, altered skin temperature, and motor dysfunction. Although previous gene expression profiling studies have been conducted in animal pain models, there genome-wide expression profiling in the whole blood of CRPS patients has not been reported yet. Here, we successfully identified certain pain-related genes through genome-wide expression profiling in the blood from CRPS patients. We found that 80 genes were differentially expressed between 4 CRPS patients (2 CRPS I and 2 CRPS II) and 5 controls (cut-off value: 1.5-fold change and pCRPS patients and 18 controls by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). We focused on the MMP9 gene that, by qRT-PCR, showed a statistically significant difference in expression in CRPS patients compared to controls with the highest relative fold change (4.0±1.23 times and p = 1.4×10−4). The up-regulation of MMP9 gene in the blood may be related to the pain progression in CRPS patients. Our findings, which offer a valuable contribution to the understanding of the differential gene expression in CRPS may help in the understanding of the pathophysiology of CRPS pain progression. PMID:24244504

Translation elicits a growth rate-dependent, genome-wide, differential protein production in Bacillus subtilis.

Science.gov (United States)

Borkowski, Olivier; Goelzer, Anne; Schaffer, Marc; Calabre, Magali; Mäder, Ulrike; Aymerich, Stéphane; Jules, Matthieu; Fromion, Vincent

2016-05-17

Complex regulatory programs control cell adaptation to environmental changes by setting condition-specific proteomes. In balanced growth, bacterial protein abundances depend on the dilution rate, transcript abundances and transcript-specific translation efficiencies. We revisited the current theory claiming the invariance of bacterial translation efficiency. By integrating genome-wide transcriptome datasets and datasets from a library of synthetic gfp-reporter fusions, we demonstrated that translation efficiencies in Bacillus subtilis decreased up to fourfold from slow to fast growth. The translation initiation regions elicited a growth rate-dependent, differential production of proteins without regulators, hence revealing a unique, hard-coded, growth rate-dependent mode of regulation. We combined model-based data analyses of transcript and protein abundances genome-wide and revealed that this global regulation is extensively used in B. subtilis We eventually developed a knowledge-based, three-step translation initiation model, experimentally challenged the model predictions and proposed that a growth rate-dependent drop in free ribosome abundance accounted for the differential protein production. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

Genome-wide identification and analysis of the chicken basic helix-loop-helix factors.

Science.gov (United States)

Liu, Wu-Yi; Zhao, Chun-Jiang

2010-01-01

Members of the basic helix-loop-helix (bHLH) family of transcription factors play important roles in a wide range of developmental processes. In this study, we conducted a genome-wide survey using the chicken (Gallus gallus) genomic database, and identified 104 bHLH sequences belonging to 42 gene families in an effort to characterize the chicken bHLH transcription factor family. Phylogenetic analyses revealed that chicken has 50, 21, 15, 4, 8, and 3 bHLH members in groups A, B, C, D, E, and F, respectively, while three members belonging to none of these groups were classified as ''orphans". A comparison between chicken and human bHLH repertoires suggested that both organisms have a number of lineage-specific bHLH members in the proteomes. Chromosome distribution patterns and phylogenetic analyses strongly suggest that the bHLH members should have arisen through gene duplication at an early date. Gene Ontology (GO) enrichment statistics showed 51 top GO annotations of biological processes counted in the frequency. The present study deepens our understanding of the chicken bHLH transcription factor family and provides much useful information for further studies using chicken as a model system.

Genome-wide analysis of the Dof transcription factor gene family reveals soybean-specific duplicable and functional characteristics.

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Yong Guo

Full Text Available The Dof domain protein family is a classic plant-specific zinc-finger transcription factor family involved in a variety of biological processes. There is great diversity in the number of Dof genes in different plants. However, there are only very limited reports on the characterization of Dof transcription factors in soybean (Glycine max. In the present study, 78 putative Dof genes were identified from the whole-genome sequence of soybean. The predicted GmDof genes were non-randomly distributed within and across 19 out of 20 chromosomes and 97.4% (38 pairs were preferentially retained duplicate paralogous genes located in duplicated regions of the genome. Soybean-specific segmental duplications contributed significantly to the expansion of the soybean Dof gene family. These Dof proteins were phylogenetically clustered into nine distinct subgroups among which the gene structure and motif compositions were considerably conserved. Comparative phylogenetic analysis of these Dof proteins revealed four major groups, similar to those reported for Arabidopsis and rice. Most of the GmDofs showed specific expression patterns based on RNA-seq data analyses. The expression patterns of some duplicate genes were partially redundant while others showed functional diversity, suggesting the occurrence of sub-functionalization during subsequent evolution. Comprehensive expression profile analysis also provided insights into the soybean-specific functional divergence among members of the Dof gene family. Cis-regulatory element analysis of these GmDof genes suggested diverse functions associated with different processes. Taken together, our results provide useful information for the functional characterization of soybean Dof genes by combining phylogenetic analysis with global gene-expression profiling.

DNA Breaks and End Resection Measured Genome-wide by End Sequencing.

Science.gov (United States)

Canela, Andres; Sridharan, Sriram; Sciascia, Nicholas; Tubbs, Anthony; Meltzer, Paul; Sleckman, Barry P; Nussenzweig, André

2016-09-01

DNA double-strand breaks (DSBs) arise during physiological transcription, DNA replication, and antigen receptor diversification. Mistargeting or misprocessing of DSBs can result in pathological structural variation and mutation. Here we describe a sensitive method (END-seq) to monitor DNA end resection and DSBs genome-wide at base-pair resolution in vivo. We utilized END-seq to determine the frequency and spectrum of restriction-enzyme-, zinc-finger-nuclease-, and RAG-induced DSBs. Beyond sequence preference, chromatin features dictate the repertoire of these genome-modifying enzymes. END-seq can detect at least one DSB per cell among 10,000 cells not harboring DSBs, and we estimate that up to one out of 60 cells contains off-target RAG cleavage. In addition to site-specific cleavage, we detect DSBs distributed over extended regions during immunoglobulin class-switch recombination. Thus, END-seq provides a snapshot of DNA ends genome-wide, which can be utilized for understanding genome-editing specificities and the influence of chromatin on DSB pathway choice. Published by Elsevier Inc.

Decoherence in yeast cell populations and its implications for genome-wide expression noise.

Science.gov (United States)

Briones, M R S; Bosco, F

2009-01-20

Gene expression "noise" is commonly defined as the stochastic variation of gene expression levels in different cells of the same population under identical growth conditions. Here, we tested whether this "noise" is amplified with time, as a consequence of decoherence in global gene expression profiles (genome-wide microarrays) of synchronized cells. The stochastic component of transcription causes fluctuations that tend to be amplified as time progresses, leading to a decay of correlations of expression profiles, in perfect analogy with elementary relaxation processes. Measuring decoherence, defined here as a decay in the auto-correlation function of yeast genome-wide expression profiles, we found a slowdown in the decay of correlations, opposite to what would be expected if, as in mixing systems, correlations decay exponentially as the equilibrium state is reached. Our results indicate that the populational variation in gene expression (noise) is a consequence of temporal decoherence, in which the slow decay of correlations is a signature of strong interdependence of the transcription dynamics of different genes.

Genome-Wide Identification and Characterization of BrrTCP Transcription Factors in Brassica rapa ssp. rapa

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Jiancan Du

2017-09-01

Full Text Available The teosinte branched1/cycloidea/proliferating cell factor (TCP gene family is a plant-specific transcription factor that participates in the control of plant development by regulating cell proliferation. However, no report is currently available about this gene family in turnips (Brassica rapa ssp. rapa. In this study, a genome-wide analysis of TCP genes was performed in turnips. Thirty-nine TCP genes in turnip genome were identified and distributed on 10 chromosomes. Phylogenetic analysis clearly showed that the family was classified as two clades: class I and class II. Gene structure and conserved motif analysis showed that the same clade genes have similar gene structures and conserved motifs. The expression profiles of 39 TCP genes were determined through quantitative real-time PCR. Most CIN-type BrrTCP genes were highly expressed in leaf. The members of CYC/TB1 subclade are highly expressed in flower bud and weakly expressed in root. By contrast, class I clade showed more widespread but less tissue-specific expression patterns. Yeast two-hybrid data show that BrrTCP proteins preferentially formed heterodimers. The function of BrrTCP2 was confirmed through ectopic expression of BrrTCP2 in wild-type and loss-of-function ortholog mutant of Arabidopsis. Overexpression of BrrTCP2 in wild-type Arabidopsis resulted in the diminished leaf size. Overexpression of BrrTCP2 in triple mutants of tcp2/4/10 restored the leaf phenotype of tcp2/4/10 to the phenotype of wild type. The comprehensive analysis of turnip TCP gene family provided the foundation to further study the roles of TCP genes in turnips.

Genome-wide Comparative Analyses Reveal the Dynamic Evolution of Nucleotide-Binding Leucine-Rich Repeat Gene Family among Solanaceae Plants

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Eunyoung Seo

2016-08-01

Full Text Available Plants have evolved an elaborate innate immune system against invading pathogens. Within this system, intracellular nucleotide-binding leucine-rich repeat (NLR immune receptors are known play critical roles in effector-triggered immunity (ETI plant defense. We performed genome-wide identification and classification of NLR-coding sequences from the genomes of pepper, tomato, and potato using fixed criteria. We then compared genomic duplication and evolution features. We identified intact 267, 443, and 755 NLR-encoding genes in tomato, potato, and pepper genomes, respectively. Phylogenetic analyses and classification of Solanaceae NLRs revealed that the majority of NLR super family members fell into 14 subgroups, including a TIR-NLR (TNL subgroup and 13 non-TNL subgroups. Specific subgroups have expanded in each genome, with the expansion in pepper showing subgroup-specific physical clusters. Comparative analysis of duplications showed distinct duplication patterns within pepper and among Solanaceae plants suggesting subgroup- or species-specific gene duplication events after speciation, resulting in divergent evolution. Taken together, genome-wide analyses of NLR family members provide insights into their evolutionary history in Solanaceae. These findings also provide important foundational knowledge for understanding NLR evolution and will empower broader characterization of disease resistance genes to be used for crop breeding.

Broad genomic and transcriptional analysis reveals a highly derived genome in dinoflagellate mitochondria

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Keeling Patrick J

2007-09-01

Full Text Available Abstract Background Dinoflagellates comprise an ecologically significant and diverse eukaryotic phylum that is sister to the phylum containing apicomplexan endoparasites. The mitochondrial genome of apicomplexans is uniquely reduced in gene content and size, encoding only three proteins and two ribosomal RNAs (rRNAs within a highly compacted 6 kb DNA. Dinoflagellate mitochondrial genomes have been comparatively poorly studied: limited available data suggest some similarities with apicomplexan mitochondrial genomes but an even more radical type of genomic organization. Here, we investigate structure, content and expression of dinoflagellate mitochondrial genomes. Results From two dinoflagellates, Crypthecodinium cohnii and Karlodinium micrum, we generated over 42 kb of mitochondrial genomic data that indicate a reduced gene content paralleling that of mitochondrial genomes in apicomplexans, i.e., only three protein-encoding genes and at least eight conserved components of the highly fragmented large and small subunit rRNAs. Unlike in apicomplexans, dinoflagellate mitochondrial genes occur in multiple copies, often as gene fragments, and in numerous genomic contexts. Analysis of cDNAs suggests several novel aspects of dinoflagellate mitochondrial gene expression. Polycistronic transcripts were found, standard start codons are absent, and oligoadenylation occurs upstream of stop codons, resulting in the absence of termination codons. Transcripts of at least one gene, cox3, are apparently trans-spliced to generate full-length mRNAs. RNA substitutional editing, a process previously identified for mRNAs in dinoflagellate mitochondria, is also implicated in rRNA expression. Conclusion The dinoflagellate mitochondrial genome shares the same gene complement and fragmentation of rRNA genes with its apicomplexan counterpart. However, it also exhibits several unique characteristics. Most notable are the expansion of gene copy numbers and their arrangements

Genome-wide analysis of poly(A) site selection in Schizosaccharomyces pombe

KAUST Repository

Schlackow, M.

2013-10-23

Polyadenylation of pre-mRNAs, a critical step in eukaryotic gene expression, is mediated by cis elements collectively called the polyadenylation signal. Genome-wide analysis of such polyadenylation signals was missing in fission yeast, even though it is an important model organism. We demonstrate that the canonical AATAAA motif is the most frequent and functional polyadenylation signal in Schizosaccharomyces pombe. Using analysis of RNA-Seq data sets from cells grown under various physiological conditions, we identify 3\\' UTRs for nearly 90% of the yeast genes. Heterogeneity of cleavage sites is common, as is alternative polyadenylation within and between conditions. We validated the computationally identified sequence elements likely to promote polyadenylation by functional assays, including qRT-PCR and 3\\'RACE analysis. The biological importance of the AATAAA motif is underlined by functional analysis of the genes containing it. Furthermore, it has been shown that convergent genes require trans elements, like cohesin for efficient transcription termination. Here we show that convergent genes lacking cohesin (on chromosome 2) are generally associated with longer overlapping mRNA transcripts. Our bioinformatic and experimental genome-wide results are summarized and can be accessed and customized in a user-friendly database Pomb(A).

Genome-wide analysis of poly(A) site selection in Schizosaccharomyces pombe

KAUST Repository

Schlackow, M.; Marguerat, S.; Proudfoot, N. J.; Bahler, J.; Erban, R.; Gullerova, M.

2013-01-01

Polyadenylation of pre-mRNAs, a critical step in eukaryotic gene expression, is mediated by cis elements collectively called the polyadenylation signal. Genome-wide analysis of such polyadenylation signals was missing in fission yeast, even though it is an important model organism. We demonstrate that the canonical AATAAA motif is the most frequent and functional polyadenylation signal in Schizosaccharomyces pombe. Using analysis of RNA-Seq data sets from cells grown under various physiological conditions, we identify 3' UTRs for nearly 90% of the yeast genes. Heterogeneity of cleavage sites is common, as is alternative polyadenylation within and between conditions. We validated the computationally identified sequence elements likely to promote polyadenylation by functional assays, including qRT-PCR and 3'RACE analysis. The biological importance of the AATAAA motif is underlined by functional analysis of the genes containing it. Furthermore, it has been shown that convergent genes require trans elements, like cohesin for efficient transcription termination. Here we show that convergent genes lacking cohesin (on chromosome 2) are generally associated with longer overlapping mRNA transcripts. Our bioinformatic and experimental genome-wide results are summarized and can be accessed and customized in a user-friendly database Pomb(A).

Transcriptional Regulation During Zygotic Genome Activation in Zebrafish and Other Anamniote Embryos.

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Wragg, J; Müller, F

2016-01-01

embryological tools and genome-wide assays. In this review we summarize recent advances in the characterization of epigenetic regulation, transcription control, and gene promoter function during zygotic genome activation and how they fit with old models for the mechanisms of the maternal to zygotic transition. This review will focus on the zebrafish embryo but draw comparisons with other vertebrate model systems and refer to invertebrate models where informative. Copyright © 2016 Elsevier Inc. All rights reserved.

Genome-Wide Methylome Analyses Reveal Novel Epigenetic Regulation Patterns in Schizophrenia and Bipolar Disorder

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Li, Yongsheng; Camarillo, Cynthia; Xu, Juan; Arana, Tania Bedard; Xiao, Yun; Zhao, Zheng; Chen, Hong; Ramirez, Mercedes; Zavala, Juan; Escamilla, Michael A.; Armas, Regina; Mendoza, Ricardo; Ontiveros, Alfonso; Nicolini, Humberto; Jerez Magaña, Alvaro Antonio; Rubin, Lewis P.; Li, Xia; Xu, Chun

2015-01-01

Schizophrenia (SZ) and bipolar disorder (BP) are complex genetic disorders. Their appearance is also likely informed by as yet only partially described epigenetic contributions. Using a sequencing-based method for genome-wide analysis, we quantitatively compared the blood DNA methylation landscapes in SZ and BP subjects to control, both in an understudied population, Hispanics along the US-Mexico border. Remarkably, we identified thousands of differentially methylated regions for SZ and BP preferentially located in promoters 3′-UTRs and 5′-UTRs of genes. Distinct patterns of aberrant methylation of promoter sequences were located surrounding transcription start sites. In these instances, aberrant methylation occurred in CpG islands (CGIs) as well as in flanking regions as well as in CGI sparse promoters. Pathway analysis of genes displaying these distinct aberrant promoter methylation patterns showed enhancement of epigenetic changes in numerous genes previously related to psychiatric disorders and neurodevelopment. Integration of gene expression data further suggests that in SZ aberrant promoter methylation is significantly associated with altered gene transcription. In particular, we found significant associations between (1) promoter CGIs hypermethylation with gene repression and (2) CGI 3′-shore hypomethylation with increased gene expression. Finally, we constructed a specific methylation analysis platform that facilitates viewing and comparing aberrant genome methylation in human neuropsychiatric disorders. PMID:25734057

Comparative Genomics and Transcriptional Analysis of Prophages Identified in the Genomes of Lactobacillus gasseri, Lactobacillus salivarius, and Lactobacillus casei†

Science.gov (United States)

Ventura, Marco; Canchaya, Carlos; Bernini, Valentina; Altermann, Eric; Barrangou, Rodolphe; McGrath, Stephen; Claesson, Marcus J.; Li, Yin; Leahy, Sinead; Walker, Carey D.; Zink, Ralf; Neviani, Erasmo; Steele, Jim; Broadbent, Jeff; Klaenhammer, Todd R.; Fitzgerald, Gerald F.; O'Toole, Paul W.; van Sinderen, Douwe

2006-01-01

Lactobacillus gasseri ATCC 33323, Lactobacillus salivarius subsp. salivarius UCC 118, and Lactobacillus casei ATCC 334 contain one (LgaI), four (Sal1, Sal2, Sal3, Sal4), and one (Lca1) distinguishable prophage sequences, respectively. Sequence analysis revealed that LgaI, Lca1, Sal1, and Sal2 prophages belong to the group of Sfi11-like pac site and cos site Siphoviridae, respectively. Phylogenetic investigation of these newly described prophage sequences revealed that they have not followed an evolutionary development similar to that of their bacterial hosts and that they show a high degree of diversity, even within a species. The attachment sites were determined for all these prophage elements; LgaI as well as Sal1 integrates in tRNA genes, while prophage Sal2 integrates in a predicted arginino-succinate lyase-encoding gene. In contrast, Lca1 and the Sal3 and Sal4 prophage remnants are integrated in noncoding regions in the L. casei ATCC 334 and L. salivarius UCC 118 genomes. Northern analysis showed that large parts of the prophage genomes are transcriptionally silent and that transcription is limited to genome segments located near the attachment site. Finally, pulsed-field gel electrophoresis followed by Southern blot hybridization with specific prophage probes indicates that these prophage sequences are narrowly distributed within lactobacilli. PMID:16672450

Genome-Wide Characterization and Expression Profiling of the AUXIN RESPONSE FACTOR (ARF) Gene Family in Eucalyptus grandis

Science.gov (United States)

Yu, Hong; Soler, Marçal; Mila, Isabelle; San Clemente, Hélène; Savelli, Bruno; Dunand, Christophe; Paiva, Jorge A. P.; Myburg, Alexander A.; Bouzayen, Mondher; Grima-Pettenati, Jacqueline; Cassan-Wang, Hua

2014-01-01

Auxin is a central hormone involved in a wide range of developmental processes including the specification of vascular stem cells. Auxin Response Factors (ARF) are important actors of the auxin signalling pathway, regulating the transcription of auxin-responsive genes through direct binding to their promoters. The recent availability of the Eucalyptus grandis genome sequence allowed us to examine the characteristics and evolutionary history of this gene family in a woody plant of high economic importance. With 17 members, the E. grandis ARF gene family is slightly contracted, as compared to those of most angiosperms studied hitherto, lacking traces of duplication events. In silico analysis of alternative transcripts and gene truncation suggested that these two mechanisms were preeminent in shaping the functional diversity of the ARF family in Eucalyptus. Comparative phylogenetic analyses with genomes of other taxonomic lineages revealed the presence of a new ARF clade found preferentially in woody and/or perennial plants. High-throughput expression profiling among different organs and tissues and in response to environmental cues highlighted genes expressed in vascular cambium and/or developing xylem, responding dynamically to various environmental stimuli. Finally, this study allowed identification of three ARF candidates potentially involved in the auxin-regulated transcriptional program underlying wood formation. PMID:25269088

Genome-wide characterization and expression profiling of the AUXIN RESPONSE FACTOR (ARF gene family in Eucalyptus grandis.

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Hong Yu

Full Text Available Auxin is a central hormone involved in a wide range of developmental processes including the specification of vascular stem cells. Auxin Response Factors (ARF are important actors of the auxin signalling pathway, regulating the transcription of auxin-responsive genes through direct binding to their promoters. The recent availability of the Eucalyptus grandis genome sequence allowed us to examine the characteristics and evolutionary history of this gene family in a woody plant of high economic importance. With 17 members, the E. grandis ARF gene family is slightly contracted, as compared to those of most angiosperms studied hitherto, lacking traces of duplication events. In silico analysis of alternative transcripts and gene truncation suggested that these two mechanisms were preeminent in shaping the functional diversity of the ARF family in Eucalyptus. Comparative phylogenetic analyses with genomes of other taxonomic lineages revealed the presence of a new ARF clade found preferentially in woody and/or perennial plants. High-throughput expression profiling among different organs and tissues and in response to environmental cues highlighted genes expressed in vascular cambium and/or developing xylem, responding dynamically to various environmental stimuli. Finally, this study allowed identification of three ARF candidates potentially involved in the auxin-regulated transcriptional program underlying wood formation.

Large-scale integration of small molecule-induced genome-wide transcriptional responses, Kinome-wide binding affinities and cell-growth inhibition profiles reveal global trends characterizing systems-level drug action

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Dusica eVidovic

2014-09-01

Full Text Available The Library of Integrated Network-based Cellular Signatures (LINCS project is a large-scale coordinated effort to build a comprehensive systems biology reference resource. The goals of the program include the generation of a very large multidimensional data matrix and informatics and computational tools to integrate, analyze, and make the data readily accessible. LINCS data include genome-wide transcriptional signatures, biochemical protein binding profiles, cellular phenotypic response profiles and various other datasets for a wide range of cell model systems and molecular and genetic perturbations. Here we present a partial survey of this data facilitated by data standards and in particular a robust compound standardization workflow; we integrated several types of LINCS signatures and analyzed the results with a focus on mechanism of action and chemical compounds. We illustrate how kinase targets can be related to disease models and relevant drugs. We identified some fundamental trends that appear to link Kinome binding profiles and transcriptional signatures to chemical information and biochemical binding profiles to transcriptional responses independent of chemical similarity. To fill gaps in the datasets we developed and applied predictive models. The results can be interpreted at the systems level as demonstrated based on a large number of signaling pathways. We can identify clear global relationships, suggesting robustness of cellular responses to chemical perturbation. Overall, the results suggest that chemical similarity is a useful measure at the systems level, which would support phenotypic drug optimization efforts. With this study we demonstrate the potential of such integrated analysis approaches and suggest prioritizing further experiments to fill the gaps in the current data.

Genome-Wide Search for Competing Endogenous RNAs Responsible for the Effects Induced by Ebola Virus Replication and Transcription Using a trVLP System

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Zhong-Yi Wang

2017-11-01

Full Text Available Understanding how infected cells respond to Ebola virus (EBOV and how this response changes during the process of viral replication and transcription are very important for establishing effective antiviral strategies. In this study, we conducted a genome-wide screen to identify long non-coding RNAs (lncRNAs, circular RNAs (circRNAs, micro RNAs (miRNAs, and mRNAs differentially expressed during replication and transcription using a tetracistronic transcription and replication-competent virus-like particle (trVLP system that models the life cycle of EBOV in 293T cells. To characterize the expression patterns of these differentially expressed RNAs, we performed a series cluster analysis, and up- or down-regulated genes were selected to establish a gene co-expression network. Competing endogenous RNA (ceRNA networks based on the RNAs responsible for the effects induced by EBOV replication and transcription in human cells, including circRNAs, lncRNAs, miRNAs, and mRNAs, were constructed for the first time. Based on these networks, the interaction details of circRNA-chr19 were explored. Our results demonstrated that circRNA-chr19 targeting miR-30b-3p regulated CLDN18 expression by functioning as a ceRNA. These findings may have important implications for further studies of the mechanisms of EBOV replication and transcription. These RNAs potentially have important functions and may be promising targets for EBOV therapy.

Genome-wide analysis of differential transcriptional and epigenetic variability across human immune cell types

DEFF Research Database (Denmark)

Ecker, Simone; Chen, Lu; Pancaldi, Vera

2017-01-01

Background: A healthy immune system requires immune cells that adapt rapidly to environmental challenges. This phenotypic plasticity can be mediated by transcriptional and epigenetic variability. Results: We apply a novel analytical approach to measure and compare transcriptional and epigenetic v...

Genome-Wide Identification and Analysis of the Chicken Basic Helix-Loop-Helix Factors

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Wu-yi Liu

2010-01-01

Full Text Available Members of the basic helix-loop-helix (bHLH family of transcription factors play important roles in a wide range of developmental processes. In this study, we conducted a genome-wide survey using the chicken (Gallus gallus genomic database, and identified 104 bHLH sequences belonging to 42 gene families in an effort to characterize the chicken bHLH transcription factor family. Phylogenetic analyses revealed that chicken has 50, 21, 15, 4, 8, and 3 bHLH members in groups A, B, C, D, E, and F, respectively, while three members belonging to none of these groups were classified as ‘‘orphans’’. A comparison between chicken and human bHLH repertoires suggested that both organisms have a number of lineage-specific bHLH members in the proteomes. Chromosome distribution patterns and phylogenetic analyses strongly suggest that the bHLH members should have arisen through gene duplication at an early date. Gene Ontology (GO enrichment statistics showed 51 top GO annotations of biological processes counted in the frequency. The present study deepens our understanding of the chicken bHLH transcription factor family and provides much useful information for further studies using chicken as a model system.

Transcriptional Slippage and RNA Editing Increase the Diversity of Transcripts in Chloroplasts: Insight from Deep Sequencing of Vigna radiata Genome and Transcriptome.

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Ching-Ping Lin

Full Text Available We performed deep sequencing of the nuclear and organellar genomes of three mungbean genotypes: Vigna radiata ssp. sublobata TC1966, V. radiata var. radiata NM92 and the recombinant inbred line RIL59 derived from a cross between TC1966 and NM92. Moreover, we performed deep sequencing of the RIL59 transcriptome to investigate transcript variability. The mungbean chloroplast genome has a quadripartite structure including a pair of inverted repeats separated by two single copy regions. A total of 213 simple sequence repeats were identified in the chloroplast genomes of NM92 and RIL59; 78 single nucleotide variants and nine indels were discovered in comparing the chloroplast genomes of TC1966 and NM92. Analysis of the mungbean chloroplast transcriptome revealed mRNAs that were affected by transcriptional slippage and RNA editing. Transcriptional slippage frequency was positively correlated with the length of simple sequence repeats of the mungbean chloroplast genome (R2=0.9911. In total, 41 C-to-U editing sites were found in 23 chloroplast genes and in one intergenic spacer. No editing site that swapped U to C was found. A combination of bioinformatics and experimental methods revealed that the plastid-encoded RNA polymerase-transcribed genes psbF and ndhA are affected by transcriptional slippage in mungbean and in main lineages of land plants, including three dicots (Glycine max, Brassica rapa, and Nicotiana tabacum, two monocots (Oryza sativa and Zea mays, two gymnosperms (Pinus taeda and Ginkgo biloba and one moss (Physcomitrella patens. Transcript analysis of the rps2 gene showed that transcriptional slippage could affect transcripts at single sequence repeat regions with poly-A runs. It showed that transcriptional slippage together with incomplete RNA editing may cause sequence diversity of transcripts in chloroplasts of land plants.

Genome-wide comparative analysis of phylogenetic trees: the prokaryotic forest of life.

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Puigbò, Pere; Wolf, Yuri I; Koonin, Eugene V

2012-01-01

Genome-wide comparison of phylogenetic trees is becoming an increasingly common approach in evolutionary genomics, and a variety of approaches for such comparison have been developed. In this article, we present several methods for comparative analysis of large numbers of phylogenetic trees. To compare phylogenetic trees taking into account the bootstrap support for each internal branch, the Boot-Split Distance (BSD) method is introduced as an extension of the previously developed Split Distance method for tree comparison. The BSD method implements the straightforward idea that comparison of phylogenetic trees can be made more robust by treating tree splits differentially depending on the bootstrap support. Approaches are also introduced for detecting tree-like and net-like evolutionary trends in the phylogenetic Forest of Life (FOL), i.e., the entirety of the phylogenetic trees for conserved genes of prokaryotes. The principal method employed for this purpose includes mapping quartets of species onto trees to calculate the support of each quartet topology and so to quantify the tree and net contributions to the distances between species. We describe the application of these methods to analyze the FOL and the results obtained with these methods. These results support the concept of the Tree of Life (TOL) as a central evolutionary trend in the FOL as opposed to the traditional view of the TOL as a "species tree."

Genome-wide analysis of WRKY gene family in Cucumis sativus.

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Ling, Jian; Jiang, Weijie; Zhang, Ying; Yu, Hongjun; Mao, Zhenchuan; Gu, Xingfang; Huang, Sanwen; Xie, Bingyan

2011-09-28

WRKY proteins are a large family of transcriptional regulators in higher plant. They are involved in many biological processes, such as plant development, metabolism, and responses to biotic and abiotic stresses. Prior to the present study, only one full-length cucumber WRKY protein had been reported. The recent publication of the draft genome sequence of cucumber allowed us to conduct a genome-wide search for cucumber WRKY proteins, and to compare these positively identified proteins with their homologs in model plants, such as Arabidopsis. We identified a total of 55 WRKY genes in the cucumber genome. According to structural features of their encoded proteins, the cucumber WRKY (CsWRKY) genes were classified into three groups (group 1-3). Analysis of expression profiles of CsWRKY genes indicated that 48 WRKY genes display differential expression either in their transcript abundance or in their expression patterns under normal growth conditions, and 23 WRKY genes were differentially expressed in response to at least one abiotic stresses (cold, drought or salinity). The expression profile of stress-inducible CsWRKY genes were correlated with those of their putative Arabidopsis WRKY (AtWRKY) orthologs, except for the group 3 WRKY genes. Interestingly, duplicated group 3 AtWRKY genes appear to have been under positive selection pressure during evolution. In contrast, there was no evidence of recent gene duplication or positive selection pressure among CsWRKY group 3 genes, which may have led to the expressional divergence of group 3 orthologs. Fifty-five WRKY genes were identified in cucumber and the structure of their encoded proteins, their expression, and their evolution were examined. Considering that there has been extensive expansion of group 3 WRKY genes in angiosperms, the occurrence of different evolutionary events could explain the functional divergence of these genes.

The prophages of Lactobacillus johnsonii NCC 533: comparative genomics and transcription analysis

International Nuclear Information System (INIS)

Ventura, Marco; Canchaya, Carlos; Pridmore, R. David; Bruessow, Harald

2004-01-01

Two non-inducible, but apparently complete prophages were identified in the genome of the sequenced Lactobacillus johnsonii strain NCC 533. The 38- and 40-kb-long prophages Lj928 and Lj965 represent distinct lineages of Sfi11-like pac-site Siphoviridae unrelated at the DNA sequence level. The deduced structural proteins from Lj928 demonstrated aa sequence identity with Lactococcus lactis phage TP901-1, while Lj965 shared sequence links with Streptococcus thermophilus phage O1205. With the exception of tRNA genes, inserted between DNA replication and DNA packaging genes, the transcription of the prophage was restricted to the genome segments near both attachment sites. Transcribed genes unrelated to phage functions were inserted between the phage repressor and integrase genes; one group of genes shared sequence relatedness with a mobile DNA element in Staphylococcus aureus. A short, but highly transcribed region was located between the phage lysin and right attachment site; it lacked a protein-encoding function in one prophage

Genome-wide comparative analysis of NBS-encoding genes between Brassica species and Arabidopsis thaliana.

Science.gov (United States)

Yu, Jingyin; Tehrim, Sadia; Zhang, Fengqi; Tong, Chaobo; Huang, Junyan; Cheng, Xiaohui; Dong, Caihua; Zhou, Yanqiu; Qin, Rui; Hua, Wei; Liu, Shengyi

2014-01-03

Plant disease resistance (R) genes with the nucleotide binding site (NBS) play an important role in offering resistance to pathogens. The availability of complete genome sequences of Brassica oleracea and Brassica rapa provides an important opportunity for researchers to identify and characterize NBS-encoding R genes in Brassica species and to compare with analogues in Arabidopsis thaliana based on a comparative genomics approach. However, little is known about the evolutionary fate of NBS-encoding genes in the Brassica lineage after split from A. thaliana. Here we present genome-wide analysis of NBS-encoding genes in B. oleracea, B. rapa and A. thaliana. Through the employment of HMM search and manual curation, we identified 157, 206 and 167 NBS-encoding genes in B. oleracea, B. rapa and A. thaliana genomes, respectively. Phylogenetic analysis among 3 species classified NBS-encoding genes into 6 subgroups. Tandem duplication and whole genome triplication (WGT) analyses revealed that after WGT of the Brassica ancestor, NBS-encoding homologous gene pairs on triplicated regions in Brassica ancestor were deleted or lost quickly, but NBS-encoding genes in Brassica species experienced species-specific gene amplification by tandem duplication after divergence of B. rapa and B. oleracea. Expression profiling of NBS-encoding orthologous gene pairs indicated the differential expression pattern of retained orthologous gene copies in B. oleracea and B. rapa. Furthermore, evolutionary analysis of CNL type NBS-encoding orthologous gene pairs among 3 species suggested that orthologous genes in B. rapa species have undergone stronger negative selection than those in B .oleracea species. But for TNL type, there are no significant differences in the orthologous gene pairs between the two species. This study is first identification and characterization of NBS-encoding genes in B. rapa and B. oleracea based on whole genome sequences. Through tandem duplication and whole genome

Genome-Wide Analysis of the Expression of WRKY Family Genes in Different Developmental Stages of Wild Strawberry (Fragaria vesca Fruit.

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Heying Zhou

Full Text Available WRKY proteins play important regulatory roles in plant developmental processes such as senescence, trichome initiation and embryo morphogenesis. In strawberry, only FaWRKY1 (Fragaria × ananassa has been characterized, leaving numerous WRKY genes to be identified and their function characterized. The publication of the draft genome sequence of the strawberry genome allowed us to conduct a genome-wide search for WRKY proteins in Fragaria vesca, and to compare the identified proteins with their homologs in model plants. Fifty-nine FvWRKY genes were identified and annotated from the F. vesca genome. Detailed analysis, including gene classification, annotation, phylogenetic evaluation, conserved motif determination and expression profiling, based on RNA-seq data, were performed on all members of the family. Additionally, the expression patterns of the WRKY genes in different fruit developmental stages were further investigated using qRT-PCR, to provide a foundation for further comparative genomics and functional studies of this important class of transcriptional regulators in strawberry.

Genome-wide identification and characterization of cacao WRKY transcription factors and analysis of their expression in response to witches' broom disease.

Science.gov (United States)

Silva Monteiro de Almeida, Dayanne; Oliveira Jordão do Amaral, Daniel; Del-Bem, Luiz-Eduardo; Bronze Dos Santos, Emily; Santana Silva, Raner José; Peres Gramacho, Karina; Vincentz, Michel; Micheli, Fabienne

2017-01-01

Transcriptional regulation, led by transcription factors (TFs) such as those of the WRKY family, is a mechanism used by the organism to enhance or repress gene expression in response to stimuli. Here, we report on the genome-wide analysis of the Theobroma cacao WRKY TF family and also investigate the expression of WRKY genes in cacao infected by the fungus Moniliophthora perniciosa. In the cacao genome, 61 non-redundant WRKY sequences were found and classified in three groups (I to III) according to the WRKY and zinc-finger motif types. The 61 putative WRKY sequences were distributed on the 10 cacao chromosomes and 24 of them came from duplication events. The sequences were phylogenetically organized according to the general WRKY groups. The phylogenetic analysis revealed that subgroups IIa and IIb are sister groups and share a common ancestor, as well as subgroups IId and IIe. The most divergent groups according to the plant origin were IIc and III. According to the phylogenetic analysis, 7 TcWRKY genes were selected and analyzed by RT-qPCR in susceptible and resistant cacao plants infected (or not) with M. perniciosa. Some TcWRKY genes presented interesting responses to M. perniciosa such as Tc01_p014750/Tc06_p013130/AtWRKY28, Tc09_p001530/Tc06_p004420/AtWRKY40, Tc04_p016130/AtWRKY54 and Tc10_p016570/ AtWRKY70. Our results can help to select appropriate candidate genes for further characterization in cacao or in other Theobroma species.

Genome-wide identification and characterization of cacao WRKY transcription factors and analysis of their expression in response to witches' broom disease

Science.gov (United States)

Silva Monteiro de Almeida, Dayanne; Oliveira Jordão do Amaral, Daniel; Del-Bem, Luiz-Eduardo; Bronze dos Santos, Emily; Santana Silva, Raner José; Peres Gramacho, Karina; Vincentz, Michel

2017-01-01

Transcriptional regulation, led by transcription factors (TFs) such as those of the WRKY family, is a mechanism used by the organism to enhance or repress gene expression in response to stimuli. Here, we report on the genome-wide analysis of the Theobroma cacao WRKY TF family and also investigate the expression of WRKY genes in cacao infected by the fungus Moniliophthora perniciosa. In the cacao genome, 61 non-redundant WRKY sequences were found and classified in three groups (I to III) according to the WRKY and zinc-finger motif types. The 61 putative WRKY sequences were distributed on the 10 cacao chromosomes and 24 of them came from duplication events. The sequences were phylogenetically organized according to the general WRKY groups. The phylogenetic analysis revealed that subgroups IIa and IIb are sister groups and share a common ancestor, as well as subgroups IId and IIe. The most divergent groups according to the plant origin were IIc and III. According to the phylogenetic analysis, 7 TcWRKY genes were selected and analyzed by RT-qPCR in susceptible and resistant cacao plants infected (or not) with M. perniciosa. Some TcWRKY genes presented interesting responses to M. perniciosa such as Tc01_p014750/Tc06_p013130/AtWRKY28, Tc09_p001530/Tc06_p004420/AtWRKY40, Tc04_p016130/AtWRKY54 and Tc10_p016570/ AtWRKY70. Our results can help to select appropriate candidate genes for further characterization in cacao or in other Theobroma species. PMID:29084273

Clinical implication of genome-wide profiling in diffuse large B-cell lymphoma and other subtypes of B-cell lymphoma

DEFF Research Database (Denmark)

Iqbal, Javeed; Joshi, Shantaram; Patel, Kavita N

2007-01-01

of Lymphoid Neoplasms (REAL) and World Health Organization (WHO) classifications. These classification methods were based on histological, immunophenotypic and cytogenetic markers and widely accepted by pathologists and oncologists worldwide. During last several decades, great progress has been made...... technology. The genome-wide transcriptional measurement, also called gene expression profile (GEP) can accurately define the biological phenotype of the tumor. In this review, important discoveries made by genome-wide GEP in understanding the biology of lymphoma and additionally the diagnostic and prognostic...

[Genome-wide identification and analysis of WRKY transcription factors in Medicago truncatula].

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Song, Hui; Nan, Zhibiao

2014-02-01

WRKY gene family plays important roles in plant by involving in transcriptional regulations during various physiologically processes such as development, metabolism and responses to biotic and abiotic stresses. WRKY genes have been identified in various plants. However, only few WRKY genes in Medicago truncatula have been identified with systematic analysis and comparison. In this study, we identified 93 WRKY genes through analyses of M. truncatula genome. These genes include 19 type-I genes, 49 type II genes and 13 type-III genes, and 12 non-regular type genes. All of these genes were characterized through analyses of gene duplication, chromosomal locations, structural diversity, conserved protein motifs and phylogenetic relations. The results showed that 11 times of gene duplication event occurred in WRKY gene family involving 24 genes. WRKY genes, containing 6 gene clusters, are unevenly distributed into chromosome 1 to 6, and there is the purifying selection pressure in WRKY group III genes.

Genome-wide analysis of Dongxiang wild rice (Oryza rufipogon Griff.) to investigate lost/acquired genes during rice domestication.

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Zhang, Fantao; Xu, Tao; Mao, Linyong; Yan, Shuangyong; Chen, Xiwen; Wu, Zhenfeng; Chen, Rui; Luo, Xiangdong; Xie, Jiankun; Gao, Shan

2016-04-26

It is widely accepted that cultivated rice (Oryza sativa L.) was domesticated from common wild rice (Oryza rufipogon Griff.). Compared to other studies which concentrate on rice origin, this study is to genetically elucidate the substantially phenotypic and physiological changes from wild rice to cultivated rice at the whole genome level. Instead of comparing two assembled genomes, this study directly compared the Dongxiang wild rice (DXWR) Illumina sequencing reads with the Nipponbare (O. sativa) complete genome without assembly of the DXWR genome. Based on the results from the comparative genomics analysis, structural variations (SVs) between DXWR and Nipponbare were determined to locate deleted genes which could have been acquired by Nipponbare during rice domestication. To overcome the limit of the SV detection, the DXWR transcriptome was also sequenced and compared with the Nipponbare transcriptome to discover the genes which could have been lost in DXWR during domestication. Both 1591 Nipponbare-acquired genes and 206 DXWR-lost transcripts were further analyzed using annotations from multiple sources. The NGS data are available in the NCBI SRA database with ID SRP070627. These results help better understanding the domestication from wild rice to cultivated rice at the whole genome level and provide a genomic data resource for rice genetic research or breeding. One finding confirmed transposable elements contribute greatly to the genome evolution from wild rice to cultivated rice. Another finding suggested the photophosphorylation and oxidative phosphorylation system in cultivated rice could have adapted to environmental changes simultaneously during domestication.

Genome-wide identification and comparative analysis of grafting-responsive mRNA in watermelon grafted onto bottle gourd and squash rootstocks by high-throughput sequencing.

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Liu, Na; Yang, Jinghua; Fu, Xinxing; Zhang, Li; Tang, Kai; Guy, Kateta Malangisha; Hu, Zhongyuan; Guo, Shaogui; Xu, Yong; Zhang, Mingfang

2016-04-01

Grafting is an important agricultural technique widely used to improve plant growth, yield, and adaptation to either biotic or abiotic stresses. However, the molecular mechanisms underlying grafting-induced physiological processes remain unclear. Watermelon (Citrullus lanatus L.) is an important horticultural crop worldwide. Grafting technique is commonly used in watermelon production for improving its tolerance to stresses, especially to the soil-borne fusarium wilt disease. In the present study, we used high-throughput sequencing to perform a genome-wide transcript analysis of scions from watermelon grafted onto bottle gourd and squash rootstocks. Our transcriptome and digital gene expression (DGE) profiling data provided insights into the molecular aspects of gene regulation in grafted watermelon. Compared with self-grafted watermelon, there were 787 and 3485 genes differentially expressed in watermelon grafted onto bottle gourd and squash rootstocks, respectively. These genes were associated with primary and secondary metabolism, hormone signaling, transcription factors, transporters, and response to stimuli. Grafting led to changes in expression of these genes, suggesting that they may play important roles in mediating the physiological processes of grafted seedlings. The potential roles of the grafting-responsive mRNAs in diverse biological and metabolic processes were discussed. Obviously, the data obtained in this study provide an excellent resource for unraveling the mechanisms of candidate genes function in diverse biological processes and in environmental adaptation in a graft system.

Genome Mutational and Transcriptional Hotspots Are Traps for Duplicated Genes and Sources of Adaptations.

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Fares, Mario A; Sabater-Muñoz, Beatriz; Toft, Christina

2017-05-01

Gene duplication generates new genetic material, which has been shown to lead to major innovations in unicellular and multicellular organisms. A whole-genome duplication occurred in the ancestor of Saccharomyces yeast species but 92% of duplicates returned to single-copy genes shortly after duplication. The persisting duplicated genes in Saccharomyces led to the origin of major metabolic innovations, which have been the source of the unique biotechnological capabilities in the Baker's yeast Saccharomyces cerevisiae. What factors have determined the fate of duplicated genes remains unknown. Here, we report the first demonstration that the local genome mutation and transcription rates determine the fate of duplicates. We show, for the first time, a preferential location of duplicated genes in the mutational and transcriptional hotspots of S. cerevisiae genome. The mechanism of duplication matters, with whole-genome duplicates exhibiting different preservation trends compared to small-scale duplicates. Genome mutational and transcriptional hotspots are rich in duplicates with large repetitive promoter elements. Saccharomyces cerevisiae shows more tolerance to deleterious mutations in duplicates with repetitive promoter elements, which in turn exhibit higher transcriptional plasticity against environmental perturbations. Our data demonstrate that the genome traps duplicates through the accelerated regulatory and functional divergence of their gene copies providing a source of novel adaptations in yeast. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Detection of anoxia-reponsive genes in cultured cells of the rainbow trout Oncorhynchus mykiss (Walbaum), using an optimized, genome-wide oligoarray

DEFF Research Database (Denmark)

Olohan, L.A.; Li, W; Wulff, Tune

2008-01-01

The breadth of mechanistic analyses of environmental stress responses is greatly enhanced by the use of contemporary post-genomic screening technologies, notably including massively parallel transcript analysis by microarray. These genome-wide investigations are entirely dependent upon the creati...

Mycoplasma hyopneumoniae Transcription Unit Organization: Genome Survey and Prediction

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Siqueira, Franciele Maboni; Schrank, Augusto; Schrank, Irene Silveira

2011-01-01

Mycoplasma hyopneumoniae is associated with swine respiratory diseases. Although gene organization and regulation are well known in many prokaryotic organisms, knowledge on mycoplasma is limited. This study performed a comparative analysis of three strains of M. hyopneumoniae (7448, J and 232), with a focus on genome organization and gene comparison for open read frame (ORF) cluster (OC) identification. An in silico analysis of gene organization demonstrated 117 OCs and 34 single ORFs in M. hyopneumoniae 7448 and J, while 116 OCs and 36 single ORFs were identified in M. hyopneumoniae 232. Genomic comparison revealed high synteny and conservation of gene order between the OCs defined for 7448 and J strains as well as for 7448 and 232 strains. Twenty-one OCs were chosen and experimentally confirmed by reverse transcription–PCR from M. hyopneumoniae 7448 genome, validating our prediction. A subset of the ORFs within an OC could be independently transcribed due to the presence of internal promoters. Our results suggest that transcription occurs in ‘run-on’ from an upstream promoter in M. hyopneumoniae, thus forming large ORF clusters (from 2 to 29 ORFs in the same orientation) and indicating a complex transcriptional organization. PMID:22086999

Genome-wide comparative analysis of metacaspases in unicellular and filamentous cyanobacteria

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Qin Song

2010-03-01

Full Text Available Abstract Background Cyanobacteria are an ancient group of photoautotrophic prokaryotes with wide variations in genome size and ecological habitat. Metacaspases (MCAs are cysteine proteinases that have sequence homology to caspases and play essential roles in programmed cell death (PCD. MCAs have been identified in several prokaryotes, fungi and plants; however, knowledge about cyanobacterial metacaspases still remains obscure. With the availability of sequenced genomes of 33 cyanobacteria, we perform a comparative analysis of metacaspases and explore their distribution, domain structure and evolution. Results A total of 58 putative MCAs were identified, which are abundant in filamentous diazotrophic cyanobacteria and Acaryochloris marina MBIC 11017 and absent in all Prochlorococcus and marine Synechococcus strains, except Synechococcus sp. PCC 7002. The Cys-His dyad of caspase superfamily is conserved, while mutations (Tyr in place of His and Ser/Asn/Gln/Gly instead of Cys are also detected in some cyanobacteria. MCAs can be classified into two major families (α and β based on the additional domain structure. Ten types and a total of 276 additional domains were identified, most of which involves in signal transduction. Apoptotic related NACHT domain was also found in two cyanobacterial MCAs. Phylogenetic tree of MCA catalytic P20 domains coincides well with the domain structure and the phylogenies based on 16s rRNA. Conclusions The existence and quantity of MCA genes in unicellular and filamentous cyanobacteria are a function of the genome size and ecological habitat. MCAs of family α and β seem to evolve separately and the recruitment of WD40 additional domain occurs later than the divergence of the two families. In this study, a general framework of sequence-structure-function connections for the metacaspases has been revealed, which may provide new targets for function investigation.

Does selection against transcriptional interference shape retroelement-free regions in mammalian genomes?

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Tobias Mourier

Full Text Available BACKGROUND: Eukaryotic genomes are scattered with retroelements that proliferate through retrotransposition. Although retroelements make up around 40 percent of the human genome, large regions are found to be completely devoid of retroelements. This has been hypothesised to be a result of genomic regions being intolerant to insertions of retroelements. The inadvertent transcriptional activity of retroelements may affect neighbouring genes, which in turn could be detrimental to an organism. We speculate that such retroelement transcription, or transcriptional interference, is a contributing factor in generating and maintaining retroelement-free regions in the human genome. METHODOLOGY/PRINCIPAL FINDINGS: Based on the known transcriptional properties of retroelements, we expect long interspersed elements (LINEs to be able to display a high degree of transcriptional interference. In contrast, we expect short interspersed elements (SINEs to display very low levels of transcriptional interference. We find that genomic regions devoid of long interspersed elements (LINEs are enriched for protein-coding genes, but that this is not the case for regions devoid of short interspersed elements (SINEs. This is expected if genes are subject to selection against transcriptional interference. We do not find microRNAs to be associated with genomic regions devoid of either SINEs or LINEs. We further observe an increased relative activity of genes overlapping LINE-free regions during early embryogenesis, where activity of LINEs has been identified previously. CONCLUSIONS/SIGNIFICANCE: Our observations are consistent with the notion that selection against transcriptional interference has contributed to the maintenance and/or generation of retroelement-free regions in the human genome.

Transient Genome-Wide Transcriptional Response to Low-Dose Ionizing Radiation In Vivo in Humans

International Nuclear Information System (INIS)

Berglund, Susanne R.; Rocke, David M.; Dai Jian; Schwietert, Chad W.; Santana, Alison; Stern, Robin L.; Lehmann, Joerg; Hartmann Siantar, Christine L.; Goldberg, Zelanna

2008-01-01

Purpose: The in vivo effects of low-dose low linear energy transfer ionizing radiation on healthy human skin are largely unknown. Using a patient-based tissue acquisition protocol, we have performed a series of genomic analyses on the temporal dynamics over a 24-hour period to determine the radiation response after a single exposure of 10 cGy. Methods and Materials: RNA from each patient tissue sample was hybridized to an Affymetrix Human Genome U133 Plus 2.0 array. Data analysis was performed on selected gene groups and pathways. Results: Nineteen gene groups and seven gene pathways that had been shown to be radiation responsive were analyzed. Of these, nine gene groups showed significant transient transcriptional changes in the human tissue samples, which returned to baseline by 24 hours postexposure. Conclusions: Low doses of ionizing radiation on full-thickness human skin produce a definable temporal response out to 24 hours postexposure. Genes involved in DNA and tissue remodeling, cell cycle transition, and inflammation show statistically significant changes in expression, despite variability between patients. These data serve as a reference for the temporal dynamics of ionizing radiation response following low-dose exposure in healthy full-thickness human skin

FGWAS: Functional genome wide association analysis.

Science.gov (United States)

Huang, Chao; Thompson, Paul; Wang, Yalin; Yu, Yang; Zhang, Jingwen; Kong, Dehan; Colen, Rivka R; Knickmeyer, Rebecca C; Zhu, Hongtu

2017-10-01

Functional phenotypes (e.g., subcortical surface representation), which commonly arise in imaging genetic studies, have been used to detect putative genes for complexly inherited neuropsychiatric and neurodegenerative disorders. However, existing statistical methods largely ignore the functional features (e.g., functional smoothness and correlation). The aim of this paper is to develop a functional genome-wide association analysis (FGWAS) framework to efficiently carry out whole-genome analyses of functional phenotypes. FGWAS consists of three components: a multivariate varying coefficient model, a global sure independence screening procedure, and a test procedure. Compared with the standard multivariate regression model, the multivariate varying coefficient model explicitly models the functional features of functional phenotypes through the integration of smooth coefficient functions and functional principal component analysis. Statistically, compared with existing methods for genome-wide association studies (GWAS), FGWAS can substantially boost the detection power for discovering important genetic variants influencing brain structure and function. Simulation studies show that FGWAS outperforms existing GWAS methods for searching sparse signals in an extremely large search space, while controlling for the family-wise error rate. We have successfully applied FGWAS to large-scale analysis of data from the Alzheimer's Disease Neuroimaging Initiative for 708 subjects, 30,000 vertices on the left and right hippocampal surfaces, and 501,584 SNPs. Copyright © 2017 Elsevier Inc. All rights reserved.

Dcode.org anthology of comparative genomic tools.

Science.gov (United States)

Loots, Gabriela G; Ovcharenko, Ivan

2005-07-01

Comparative genomics provides the means to demarcate functional regions in anonymous DNA sequences. The successful application of this method to identifying novel genes is currently shifting to deciphering the non-coding encryption of gene regulation across genomes. To facilitate the practical application of comparative sequence analysis to genetics and genomics, we have developed several analytical and visualization tools for the analysis of arbitrary sequences and whole genomes. These tools include two alignment tools, zPicture and Mulan; a phylogenetic shadowing tool, eShadow for identifying lineage- and species-specific functional elements; two evolutionary conserved transcription factor analysis tools, rVista and multiTF; a tool for extracting cis-regulatory modules governing the expression of co-regulated genes, Creme 2.0; and a dynamic portal to multiple vertebrate and invertebrate genome alignments, the ECR Browser. Here, we briefly describe each one of these tools and provide specific examples on their practical applications. All the tools are publicly available at the http://www.dcode.org/ website.

Genome-wide comparative analysis reveals human-mouse regulatory landscape and evolution.

Science.gov (United States)

Denas, Olgert; Sandstrom, Richard; Cheng, Yong; Beal, Kathryn; Herrero, Javier; Hardison, Ross C; Taylor, James

2015-02-14

Because species-specific gene expression is driven by species-specific regulation, understanding the relationship between sequence and function of the regulatory regions in different species will help elucidate how differences among species arise. Despite active experimental and computational research, relationships among sequence, conservation, and function are still poorly understood. We compared transcription factor occupied segments (TFos) for 116 human and 35 mouse TFs in 546 human and 125 mouse cell types and tissues from the Human and the Mouse ENCODE projects. We based the map between human and mouse TFos on a one-to-one nucleotide cross-species mapper, bnMapper, that utilizes whole genome alignments (WGA). Our analysis shows that TFos are under evolutionary constraint, but a substantial portion (25.1% of mouse and 25.85% of human on average) of the TFos does not have a homologous sequence on the other species; this portion varies among cell types and TFs. Furthermore, 47.67% and 57.01% of the homologous TFos sequence shows binding activity on the other species for human and mouse respectively. However, 79.87% and 69.22% is repurposed such that it binds the same TF in different cells or different TFs in the same cells. Remarkably, within the set of repurposed TFos, the corresponding genome regions in the other species are preferred locations of novel TFos. These events suggest exaptation of some functional regulatory sequences into new function. Despite TFos repurposing, we did not find substantial changes in their predicted target genes, suggesting that CRMs buffer evolutionary events allowing little or no change in the TFos - target gene associations. Thus, the small portion of TFos with strictly conserved occupancy underestimates the degree of conservation of regulatory interactions. We mapped regulatory sequences from an extensive number of TFs and cell types between human and mouse using WGA. A comparative analysis of this correspondence unveiled the

Genome-wide expressions in autologous eutopic and ectopic endometrium of fertile women with endometriosis

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Khan Meraj A

2012-09-01

Full Text Available Abstract Background In order to obtain a lead of the pathophysiology of endometriosis, genome-wide expressional analyses of eutopic and ectopic endometrium have earlier been reported, however, the effects of stages of severity and phases of menstrual cycle on expressional profiles have not been examined. The effect of genetic heterogeneity and fertility history on transcriptional activity was also not considered. In the present study, a genome-wide expression analysis of autologous, paired eutopic and ectopic endometrial samples obtained from fertile women (n = 18 suffering from moderate (stage 3; n = 8 or severe (stage 4; n = 10 ovarian endometriosis during proliferative (n = 13 and secretory (n = 5 phases of menstrual cycle was performed. Methods Individual pure RNA samples were subjected to Agilent’s Whole Human Genome 44K microarray experiments. Microarray data were validated (P  Results Higher clustering effect of pairing (cluster distance, cd = 0.1 in samples from same individuals on expressional arrays among eutopic and ectopic samples was observed as compared to that of clinical stages of severity (cd = 0.5 and phases of menstrual cycle (cd = 0.6. Post hoc analysis revealed anomaly in the expressional profiles of several genes associated with immunological, neuracrine and endocrine functions and gynecological cancers however with no overt oncogenic potential in endometriotic tissue. Dys-regulation of three (CLOCK, ESR1, and MYC major transcription factors appeared to be significant causative factors in the pathogenesis of ovarian endometriosis. A novel cohort of twenty-eight (28 genes representing potential marker for ovarian endometriosis in fertile women was discovered. Conclusions Dysfunctional expression of immuno-neuro-endocrine behaviour in endometrium appeared critical to endometriosis. Although no overt oncogenic potential was evident, several genes associated with gynecological cancers were

Genome-wide prediction of cis-regulatory regions using supervised deep learning methods.

Science.gov (United States)

Li, Yifeng; Shi, Wenqiang; Wasserman, Wyeth W

2018-05-31

In the human genome, 98% of DNA sequences are non-protein-coding regions that were previously disregarded as junk DNA. In fact, non-coding regions host a variety of cis-regulatory regions which precisely control the expression of genes. Thus, Identifying active cis-regulatory regions in the human genome is critical for understanding gene regulation and assessing the impact of genetic variation on phenotype. The developments of high-throughput sequencing and machine learning technologies make it possible to predict cis-regulatory regions genome wide. Based on rich data resources such as the Encyclopedia of DNA Elements (ENCODE) and the Functional Annotation of the Mammalian Genome (FANTOM) projects, we introduce DECRES based on supervised deep learning approaches for the identification of enhancer and promoter regions in the human genome. Due to their ability to discover patterns in large and complex data, the introduction of deep learning methods enables a significant advance in our knowledge of the genomic locations of cis-regulatory regions. Using models for well-characterized cell lines, we identify key experimental features that contribute to the predictive performance. Applying DECRES, we delineate locations of 300,000 candidate enhancers genome wide (6.8% of the genome, of which 40,000 are supported by bidirectional transcription data), and 26,000 candidate promoters (0.6% of the genome). The predicted annotations of cis-regulatory regions will provide broad utility for genome interpretation from functional genomics to clinical applications. The DECRES model demonstrates potentials of deep learning technologies when combined with high-throughput sequencing data, and inspires the development of other advanced neural network models for further improvement of genome annotations.

Enhancement of single guide RNA transcription for efficient CRISPR/Cas-based genomic engineering.

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Ui-Tei, Kumiko; Maruyama, Shohei; Nakano, Yuko

2017-06-01

Genomic engineering using clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) protein is a promising approach for targeting the genomic DNA of virtually any organism in a sequence-specific manner. Recent remarkable advances in CRISPR/Cas technology have made it a feasible system for use in therapeutic applications and biotechnology. In the CRISPR/Cas system, a guide RNA (gRNA), interacting with the Cas protein, recognizes a genomic region with sequence complementarity, and the double-stranded DNA at the target site is cleaved by the Cas protein. A widely used gRNA is an RNA polymerase III (pol III)-driven single gRNA (sgRNA), which is produced by artificial fusion of CRISPR RNA (crRNA) and trans-activation crRNA (tracrRNA). However, we identified a TTTT stretch, known as a termination signal of RNA pol III, in the scaffold region of the sgRNA. Here, we revealed that sgRNA carrying a TTTT stretch reduces the efficiency of sgRNA transcription due to premature transcriptional termination, and decreases the efficiency of genome editing. Unexpectedly, it was also shown that the premature terminated sgRNA may have an adverse effect of inducing RNA interference. Such disadvantageous effects were avoided by substituting one base in the TTTT stretch.

Heterogeneous Ribosomes Preferentially Translate Distinct Subpools of mRNAs Genome-wide.

Science.gov (United States)

Shi, Zhen; Fujii, Kotaro; Kovary, Kyle M; Genuth, Naomi R; Röst, Hannes L; Teruel, Mary N; Barna, Maria

2017-07-06

Emerging studies have linked the ribosome to more selective control of gene regulation. However, an outstanding question is whether ribosome heterogeneity at the level of core ribosomal proteins (RPs) exists and enables ribosomes to preferentially translate specific mRNAs genome-wide. Here, we measured the absolute abundance of RPs in translating ribosomes and profiled transcripts that are enriched or depleted from select subsets of ribosomes within embryonic stem cells. We find that heterogeneity in RP composition endows ribosomes with differential selectivity for translating subpools of transcripts, including those controlling metabolism, cell cycle, and development. As an example, mRNAs enriched in binding to RPL10A/uL1-containing ribosomes are shown to require RPL10A/uL1 for their efficient translation. Within several of these transcripts, this level of regulation is mediated, at least in part, by internal ribosome entry sites. Together, these results reveal a critical functional link between ribosome heterogeneity and the post-transcriptional circuitry of gene expression. Copyright © 2017 Elsevier Inc. All rights reserved.

TSSer: an automated method to identify transcription start sites in prokaryotic genomes from differential RNA sequencing data.

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Jorjani, Hadi; Zavolan, Mihaela

2014-04-01

Accurate identification of transcription start sites (TSSs) is an essential step in the analysis of transcription regulatory networks. In higher eukaryotes, the capped analysis of gene expression technology enabled comprehensive annotation of TSSs in genomes such as those of mice and humans. In bacteria, an equivalent approach, termed differential RNA sequencing (dRNA-seq), has recently been proposed, but the application of this approach to a large number of genomes is hindered by the paucity of computational analysis methods. With few exceptions, when the method has been used, annotation of TSSs has been largely done manually. In this work, we present a computational method called 'TSSer' that enables the automatic inference of TSSs from dRNA-seq data. The method rests on a probabilistic framework for identifying both genomic positions that are preferentially enriched in the dRNA-seq data as well as preferentially captured relative to neighboring genomic regions. Evaluating our approach for TSS calling on several publicly available datasets, we find that TSSer achieves high consistency with the curated lists of annotated TSSs, but identifies many additional TSSs. Therefore, TSSer can accelerate genome-wide identification of TSSs in bacterial genomes and can aid in further characterization of bacterial transcription regulatory networks. TSSer is freely available under GPL license at http://www.clipz.unibas.ch/TSSer/index.php

Genome-wide comparative analysis of codon usage bias and codon context patterns among cyanobacterial genomes.

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Prabha, Ratna; Singh, Dhananjaya P; Sinha, Swati; Ahmad, Khurshid; Rai, Anil

2017-04-01

With the increasing accumulation of genomic sequence information of prokaryotes, the study of codon usage bias has gained renewed attention. The purpose of this study was to examine codon selection pattern within and across cyanobacterial species belonging to diverse taxonomic orders and habitats. We performed detailed comparative analysis of cyanobacterial genomes with respect to codon bias. Our analysis reflects that in cyanobacterial genomes, A- and/or T-ending codons were used predominantly in the genes whereas G- and/or C-ending codons were largely avoided. Variation in the codon context usage of cyanobacterial genes corresponded to the clustering of cyanobacteria as per their GC content. Analysis of codon adaptation index (CAI) and synonymous codon usage order (SCUO) revealed that majority of genes are associated with low codon bias. Codon selection pattern in cyanobacterial genomes reflected compositional constraints as major influencing factor. It is also identified that although, mutational constraint may play some role in affecting codon usage bias in cyanobacteria, compositional constraint in terms of genomic GC composition coupled with environmental factors affected codon selection pattern in cyanobacterial genomes. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparative genomics of CytR, an unusual member of the LacI family of transcription factors.

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Natalia V Sernova

Full Text Available CytR is a transcription regulator from the LacI family, present in some gamma-proteobacteria including Escherichia coli and known not only for its cellular role, control of transport and utilization of nucleosides, but for a number of unusual structural properties. The present study addressed three related problems: structure of CytR-binding sites and motifs, their evolutionary conservation, and identification of new members of the CytR regulon. While the majority of CytR-binding sites are imperfect inverted repeats situated between binding sites for another transcription factor, CRP, other architectures were observed, in particular, direct repeats. While the similarity between sites for different genes in one genome is rather low, and hence the consensus motif is weak, there is high conservation of orthologous sites in different genomes (mainly in the Enterobacteriales arguing for the presence of specific CytR-DNA contacts. On larger evolutionary distances candidate CytR sites may migrate but the approximate distance between flanking CRP sites tends to be conserved, which demonstrates that the overall structure of the CRP-CytR-DNA complex is gene-specific. The analysis yielded candidate CytR-binding sites for orthologs of known regulon members in less studied genomes of the Enterobacteriales and Vibrionales and identified a new candidate member of the CytR regulon, encoding a transporter named NupT (YcdZ.

Identification of novel candidate genes involved in mineralization of dental enamel by genome-wide transcript profiling.

Science.gov (United States)

Lacruz, Rodrigo S; Smith, Charles E; Bringas, Pablo; Chen, Yi-Bu; Smith, Susan M; Snead, Malcolm L; Kurtz, Ira; Hacia, Joseph G; Hubbard, Michael J; Paine, Michael L

2012-05-01

The gene repertoire regulating vertebrate biomineralization is poorly understood. Dental enamel, the most highly mineralized tissue in mammals, differs from other calcifying systems in that the formative cells (ameloblasts) lack remodeling activity and largely degrade and resorb the initial extracellular matrix. Enamel mineralization requires that ameloblasts undergo a profound functional switch from matrix-secreting to maturational (calcium transport, protein resorption) roles as mineralization progresses. During the maturation stage, extracellular pH decreases markedly, placing high demands on ameloblasts to regulate acidic environments present around the growing hydroxyapatite crystals. To identify the genetic events driving enamel mineralization, we conducted genome-wide transcript profiling of the developing enamel organ from rat incisors and highlight over 300 genes differentially expressed during maturation. Using multiple bioinformatics analyses, we identified groups of maturation-associated genes whose functions are linked to key mineralization processes including pH regulation, calcium handling, and matrix turnover. Subsequent qPCR and Western blot analyses revealed that a number of solute carrier (SLC) gene family members were up-regulated during maturation, including the novel protein Slc24a4 involved in calcium handling as well as other proteins of similar function (Stim1). By providing the first global overview of the cellular machinery required for enamel maturation, this study provide a strong foundation for improving basic understanding of biomineralization and its practical applications in healthcare. Copyright © 2011 Wiley Periodicals, Inc.

Comparative analysis of prophages in Streptococcus mutans genomes

Science.gov (United States)

Fu, Tiwei; Fan, Xiangyu; Long, Quanxin; Deng, Wanyan; Song, Jinlin

2017-01-01

Prophages have been considered genetic units that have an intimate association with novel phenotypic properties of bacterial hosts, such as pathogenicity and genomic variation. Little is known about the genetic information of prophages in the genome of Streptococcus mutans, a major pathogen of human dental caries. In this study, we identified 35 prophage-like elements in S. mutans genomes and performed a comparative genomic analysis. Comparative genomic and phylogenetic analyses of prophage sequences revealed that the prophages could be classified into three main large clusters: Cluster A, Cluster B, and Cluster C. The S. mutans prophages in each cluster were compared. The genomic sequences of phismuN66-1, phismuNLML9-1, and phismu24-1 all shared similarities with the previously reported S. mutans phages M102, M102AD, and ϕAPCM01. The genomes were organized into seven major gene clusters according to the putative functions of the predicted open reading frames: packaging and structural modules, integrase, host lysis modules, DNA replication/recombination modules, transcriptional regulatory modules, other protein modules, and hypothetical protein modules. Moreover, an integrase gene was only identified in phismuNLML9-1 prophages. PMID:29158986

A novel comparative pattern count analysis reveals a chronic ethanol-induced dynamic shift in immediate early NF-κB genome-wide promoter binding during liver regeneration.

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Kuttippurathu, Lakshmi; Patra, Biswanath; Hoek, Jan B; Vadigepalli, Rajanikanth

2016-03-01

Liver regeneration after partial hepatectomy is a clinically important process that is impaired by adaptation to chronic alcohol intake. We focused on the initial time points following partial hepatectomy (PHx) to analyze the genome-wide binding activity of NF-κB, a key immediate early regulator. We investigated the effect of chronic alcohol intake on immediate early NF-κB genome-wide localization, in the adapted state as well as in response to partial hepatectomy, using chromatin immunoprecipitation followed by promoter microarray analysis. We found many ethanol-specific NF-κB binding target promoters in the ethanol-adapted state, corresponding to the regulation of biosynthetic processes, oxidation-reduction and apoptosis. Partial hepatectomy induced a diet-independent shift in NF-κB binding loci relative to the transcription start sites. We employed a novel pattern count analysis to exhaustively enumerate and compare the number of promoters corresponding to the temporal binding patterns in ethanol and pair-fed control groups. The highest pattern count corresponded to promoters with NF-κB binding exclusively in the ethanol group at 1 h post PHx. This set was associated with the regulation of cell death, response to oxidative stress, histone modification, mitochondrial function, and metabolic processes. Integration with the global gene expression profiles to identify putative transcriptional consequences of NF-κB binding patterns revealed that several of ethanol-specific 1 h binding targets showed ethanol-specific differential expression through 6 h post PHx. Motif analysis yielded co-incident binding loci for STAT3, AP-1, CREB, C/EBP-β, PPAR-γ and C/EBP-α, likely participating in co-regulatory modules with NF-κB in shaping the immediate early response to PHx. We conclude that adaptation to chronic ethanol intake disrupts the NF-κB promoter binding landscape with consequences for the immediate early gene regulatory response to the acute challenge of PHx.

Does selection against transcriptional interference shape retroelement-free regions in mammalian genomes?

DEFF Research Database (Denmark)

Mourier, Tobias; Willerslev, Eske

2008-01-01

in generating and maintaining retroelement-free regions in the human genome. METHODOLOGY/PRINCIPAL FINDINGS: Based on the known transcriptional properties of retroelements, we expect long interspersed elements (LINEs) to be able to display a high degree of transcriptional interference. In contrast, we expect......BACKGROUND: Eukaryotic genomes are scattered with retroelements that proliferate through retrotransposition. Although retroelements make up around 40 percent of the human genome, large regions are found to be completely devoid of retroelements. This has been hypothesised to be a result of genomic...... activity of LINEs has been identified previously. CONCLUSIONS/SIGNIFICANCE: Our observations are consistent with the notion that selection against transcriptional interference has contributed to the maintenance and/or generation of retroelement-free regions in the human genome....

Genomic Selection for Drought Tolerance Using Genome-Wide SNPs in Maize

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Thirunavukkarasu Nepolean

2017-04-01

Full Text Available Traditional breeding strategies for selecting superior genotypes depending on phenotypic traits have proven to be of limited success, as this direct selection is hindered by low heritability, genetic interactions such as epistasis, environmental-genotype interactions, and polygenic effects. With the advent of new genomic tools, breeders have paved a way for selecting superior breeds. Genomic selection (GS has emerged as one of the most important approaches for predicting genotype performance. Here, we tested the breeding values of 240 maize subtropical lines phenotyped for drought at different environments using 29,619 cured SNPs. Prediction accuracies of seven genomic selection models (ridge regression, LASSO, elastic net, random forest, reproducing kernel Hilbert space, Bayes A and Bayes B were tested for their agronomic traits. Though prediction accuracies of Bayes B, Bayes A and RKHS were comparable, Bayes B outperformed the other models by predicting highest Pearson correlation coefficient in all three environments. From Bayes B, a set of the top 1053 significant SNPs with higher marker effects was selected across all datasets to validate the genes and QTLs. Out of these 1053 SNPs, 77 SNPs associated with 10 drought-responsive transcription factors. These transcription factors were associated with different physiological and molecular functions (stomatal closure, root development, hormonal signaling and photosynthesis. Of several models, Bayes B has been shown to have the highest level of prediction accuracy for our data sets. Our experiments also highlighted several SNPs based on their performance and relative importance to drought tolerance. The result of our experiments is important for the selection of superior genotypes and candidate genes for breeding drought-tolerant maize hybrids.

Genome-Wide Detection and Analysis of Multifunctional Genes

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Pritykin, Yuri; Ghersi, Dario; Singh, Mona

2015-01-01

Many genes can play a role in multiple biological processes or molecular functions. Identifying multifunctional genes at the genome-wide level and studying their properties can shed light upon the complexity of molecular events that underpin cellular functioning, thereby leading to a better understanding of the functional landscape of the cell. However, to date, genome-wide analysis of multifunctional genes (and the proteins they encode) has been limited. Here we introduce a computational approach that uses known functional annotations to extract genes playing a role in at least two distinct biological processes. We leverage functional genomics data sets for three organisms—H. sapiens, D. melanogaster, and S. cerevisiae—and show that, as compared to other annotated genes, genes involved in multiple biological processes possess distinct physicochemical properties, are more broadly expressed, tend to be more central in protein interaction networks, tend to be more evolutionarily conserved, and are more likely to be essential. We also find that multifunctional genes are significantly more likely to be involved in human disorders. These same features also hold when multifunctionality is defined with respect to molecular functions instead of biological processes. Our analysis uncovers key features about multifunctional genes, and is a step towards a better genome-wide understanding of gene multifunctionality. PMID:26436655

Comparing genomic expression patterns across plant species reveals highly diverged transcriptional dynamics in response to salt stress

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Close Timothy J

2009-08-01

Full Text Available Abstract Background Rice and barley are both members of Poaceae (grass family but have a marked difference in salt tolerance. The molecular mechanism underlying this difference was previously unexplored. This study employs a comparative genomics approach to identify analogous and contrasting gene expression patterns between rice and barley. Results A hierarchical clustering approach identified several interesting expression trajectories among rice and barley genotypes. There were no major conserved expression patterns between the two species in response to salt stress. A wheat salt-stress dataset was queried for comparison with rice and barley. Roughly one-third of the salt-stress responses of barley were conserved with wheat while overlap between wheat and rice was minimal. These results demonstrate that, at transcriptome level, rice is strikingly different compared to the more closely related barley and wheat. This apparent lack of analogous transcriptional programs in response to salt stress is further highlighted through close examination of genes associated with root growth and development. Conclusion The analysis provides support for the hypothesis that conservation of transcriptional signatures in response to environmental cues depends on the genetic similarity among the genotypes within a species, and on the phylogenetic distance between the species.

Cross-species genome-wide identification of evolutionary conserved microproteins

DEFF Research Database (Denmark)

Straub, Daniel; Wenkel, Stephan

2017-01-01

Protein concept beyond transcription factors to other protein families. Here, we reveal potential microProtein candidates in several plant and animal reference genomes. A large number of these microProteins are species-specific while others evolved early and are evolutionary highly conserved. Most known micro...... act in plant transcriptional regulation, signal transduction and anatomical structure development. MiPFinder is freely available to find microProteins in any genome and will aid in the identification of novel microProteins in plants and animals....

Low-pass sequencing for microbial comparative genomics

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Kennedy Sean

2004-01-01

Full Text Available Abstract Background We studied four extremely halophilic archaea by low-pass shotgun sequencing: (1 the metabolically versatile Haloarcula marismortui; (2 the non-pigmented Natrialba asiatica; (3 the psychrophile Halorubrum lacusprofundi and (4 the Dead Sea isolate Halobaculum gomorrense. Approximately one thousand single pass genomic sequences per genome were obtained. The data were analyzed by comparative genomic analyses using the completed Halobacterium sp. NRC-1 genome as a reference. Low-pass shotgun sequencing is a simple, inexpensive, and rapid approach that can readily be performed on any cultured microbe. Results As expected, the four archaeal halophiles analyzed exhibit both bacterial and eukaryotic characteristics as well as uniquely archaeal traits. All five halophiles exhibit greater than sixty percent GC content and low isoelectric points (pI for their predicted proteins. Multiple insertion sequence (IS elements, often involved in genome rearrangements, were identified in H. lacusprofundi and H. marismortui. The core biological functions that govern cellular and genetic mechanisms of H. sp. NRC-1 appear to be conserved in these four other halophiles. Multiple TATA box binding protein (TBP and transcription factor IIB (TFB homologs were identified from most of the four shotgunned halophiles. The reconstructed molecular tree of all five halophiles shows a large divergence between these species, but with the closest relationship being between H. sp. NRC-1 and H. lacusprofundi. Conclusion Despite the diverse habitats of these species, all five halophiles share (1 high GC content and (2 low protein isoelectric points, which are characteristics associated with environmental exposure to UV radiation and hypersalinity, respectively. Identification of multiple IS elements in the genome of H. lacusprofundi and H. marismortui suggest that genome structure and dynamic genome reorganization might be similar to that previously observed in the

Integration of Genome-Wide TF Binding and Gene Expression Data to Characterize Gene Regulatory Networks in Plant Development.

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Chen, Dijun; Kaufmann, Kerstin

2017-01-01

Key transcription factors (TFs) controlling the morphogenesis of flowers and leaves have been identified in the model plant Arabidopsis thaliana. Recent genome-wide approaches based on chromatin immunoprecipitation (ChIP) followed by high-throughput DNA sequencing (ChIP-seq) enable systematic identification of genome-wide TF binding sites (TFBSs) of these regulators. Here, we describe a computational pipeline for analyzing ChIP-seq data to identify TFBSs and to characterize gene regulatory networks (GRNs) with applications to the regulatory studies of flower development. In particular, we provide step-by-step instructions on how to download, analyze, visualize, and integrate genome-wide data in order to construct GRNs for beginners of bioinformatics. The practical guide presented here is ready to apply to other similar ChIP-seq datasets to characterize GRNs of interest.

MYB Transcription Factors in Chinese Pear (Pyrus bretschneideri Rehd.: Genome-Wide Identification, Classification and Expression Profiling during Fruit Development

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Yun Peng eCao

2016-04-01

Full Text Available The MYB family is one of the largest families of transcription factors in plants. Although some MYBs have been reported to play roles in secondary metabolism, no comprehensive study of the MYB family in Chinese pear (Pyrus bretschneideri Rehd. has been reported. In the present study, we performed genome-wide analysis of MYB genes in Chinese pear, designated as PbMYBs, including analyses of their phylogenic relationships, structures, chromosomal locations, promoter regions, GO annotations and collinearity. A total of 129 PbMYB genes were identified in the pear genome and were divided into 31 subgroups based on phylogenetic analysis. These PbMYBs were unevenly distributed among 16 chromosomes (total of 17 chromosomes. The occurrence of gene duplication events indicated that whole-genome duplication and segmental duplication likely played key roles in expansion of the PbMYB gene family. Ka/Ks analysis suggested that the duplicated PbMYBs mainly experienced purifying selection with restrictive functional divergence after the duplication events. Interspecies microsynteny analysis revealed maximum orthology between pear and peach, followed by plum and strawberry. Subsequently, the expression patterns of 20 PbMYB genes that may be involved in lignin biosynthesis according to their phylogenetic relationships were examined throughout fruit development. Among the twenty genes examined, PbMYB25 and PbMYB52 exhibited expression patterns consistent with the typical variations in the lignin content previously reported. Moreover, sub-cellular localization analysis revealed that two proteins PbMYB25 and PbMYB52 were localized to the nucleus. All together, PbMYB25 and PbMYB52 were inferred to be candidate genes involved in the regulation of lignin biosynthesis during the development of pear fruit. This study provides useful information for further functional analysis of the MYB gene family in pear.

Genome-Wide Chromosomal Targets of Oncogenic Transcription Factors

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2008-04-01

Altman, W.E., Attiya, S., Bader, J.S., Bemben, L.A., Berka , J., Braverman, M.S., Chen, Y.J., Chen, Z., et al. 2005. Genome sequencing in microfabricated...software after filtering to exclude bad spots. qPCR validation. Primer pairs used in Figure 1 were designed to cover three peaks and three troughs in

Genome-wide maps of alkylation damage, repair, and mutagenesis in yeast reveal mechanisms of mutational heterogeneity.

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Mao, Peng; Brown, Alexander J; Malc, Ewa P; Mieczkowski, Piotr A; Smerdon, Michael J; Roberts, Steven A; Wyrick, John J

2017-10-01

DNA base damage is an important contributor to genome instability, but how the formation and repair of these lesions is affected by the genomic landscape and contributes to mutagenesis is unknown. Here, we describe genome-wide maps of DNA base damage, repair, and mutagenesis at single nucleotide resolution in yeast treated with the alkylating agent methyl methanesulfonate (MMS). Analysis of these maps revealed that base excision repair (BER) of alkylation damage is significantly modulated by chromatin, with faster repair in nucleosome-depleted regions, and slower repair and higher mutation density within strongly positioned nucleosomes. Both the translational and rotational settings of lesions within nucleosomes significantly influence BER efficiency; moreover, this effect is asymmetric relative to the nucleosome dyad axis and is regulated by histone modifications. Our data also indicate that MMS-induced mutations at adenine nucleotides are significantly enriched on the nontranscribed strand (NTS) of yeast genes, particularly in BER-deficient strains, due to higher damage formation on the NTS and transcription-coupled repair of the transcribed strand (TS). These findings reveal the influence of chromatin on repair and mutagenesis of base lesions on a genome-wide scale and suggest a novel mechanism for transcription-associated mutation asymmetry, which is frequently observed in human cancers. © 2017 Mao et al.; Published by Cold Spring Harbor Laboratory Press.

Widespread anti-sense transcription in apple is correlated with siRNA production and indicates a large potential for transcriptional and/or post-transcriptional control.

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Celton, Jean-Marc; Gaillard, Sylvain; Bruneau, Maryline; Pelletier, Sandra; Aubourg, Sébastien; Martin-Magniette, Marie-Laure; Navarro, Lionel; Laurens, François; Renou, Jean-Pierre

2014-07-01

Characterizing the transcriptome of eukaryotic organisms is essential for studying gene regulation and its impact on phenotype. The realization that anti-sense (AS) and noncoding RNA transcription is pervasive in many genomes has emphasized our limited understanding of gene transcription and post-transcriptional regulation. Numerous mechanisms including convergent transcription, anti-correlated expression of sense and AS transcripts, and RNAi remain ill-defined. Here, we have combined microarray analysis and high-throughput sequencing of small RNAs (sRNAs) to unravel the complexity of transcriptional and potential post-transcriptional regulation in eight organs of apple (Malus × domestica). The percentage of AS transcript expression is higher than that identified in annual plants such as rice and Arabidopsis thaliana. Furthermore, we show that a majority of AS transcripts are transcribed beyond 3'UTR regions, and may cover a significant portion of the predicted sense transcripts. Finally we demonstrate at a genome-wide scale that anti-sense transcript expression is correlated with the presence of both short (21-23 nt) and long (> 30 nt) siRNAs, and that the sRNA coverage depth varies with the level of AS transcript expression. Our study provides a new insight on the functional role of anti-sense transcripts at the genome-wide level, and a new basis for the understanding of sRNA biogenesis in plants. © 2014 INRA. New Phytologist © 2014 New Phytologist Trust.

DNA immunoprecipitation semiconductor sequencing (DIP-SC-seq) as a rapid method to generate genome wide epigenetic signatures

OpenAIRE

Thomson, John P.; Fawkes, Angie; Ottaviano, Raffaele; Hunter, Jennifer M.; Shukla, Ruchi; Mjoseng, Heidi K.; Clark, Richard; Coutts, Audrey; Murphy, Lee; Meehan, Richard R.

2015-01-01

Modification of DNA resulting in 5-methylcytosine (5 mC) or 5-hydroxymethylcytosine (5hmC) has been shown to influence the local chromatin environment and affect transcription. Although recent advances in next generation sequencing technology allow researchers to map epigenetic modifications across the genome, such experiments are often time-consuming and cost prohibitive. Here we present a rapid and cost effective method of generating genome wide DNA modification maps utilising commercially ...

Genome-wide CpG island methylation analysis implicates novel genes in the pathogenesis of renal cell carcinoma

OpenAIRE

Ricketts, Christopher J.; Morris, Mark R.; Gentle, Dean; Brown, Michael; Wake, Naomi; Woodward, Emma R.; Clarke, Noel; Latif, Farida; Maher, Eamonn R.

2012-01-01

In order to identify novel candidate tumor suppressor genes (TSGs) implicated in renal cell carcinoma (RCC), we performed genome-wide methylation profiling of RCC using the HumanMethylation27 BeadChips to assess methylation at >14,000 genes. Two hundred and twenty hypermethylated probes representing 205 loci/genes were identified in genomic CpG islands. A subset of TSGs investigated in detail exhibited frequent tumor methylation, promoter methylation associated transcriptional silencing an...

Effect of bodily fluids from honey bee (Apis mellifera) larvae on growth and genome-wide transcriptional response of the causal agent of American Foulbrood disease (Paenibacillus larvae).

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De Smet, Lina; De Koker, Dieter; Hawley, Alyse K; Foster, Leonard J; De Vos, Paul; de Graaf, Dirk C

2014-01-01

Paenibacillus larvae, the causal agent of American Foulbrood disease (AFB), affects honey bee health worldwide. The present study investigates the effect of bodily fluids from honey bee larvae on growth velocity and transcription for this Gram-positive, endospore-forming bacterium. It was observed that larval fluids accelerate the growth and lead to higher bacterial densities during stationary phase. The genome-wide transcriptional response of in vitro cultures of P. larvae to larval fluids was studied by microarray technology. Early responses of P. larvae to larval fluids are characterized by a general down-regulation of oligopeptide and sugar transporter genes, as well as by amino acid and carbohydrate metabolic genes, among others. Late responses are dominated by general down-regulation of sporulation genes and up-regulation of phage-related genes. A theoretical mechanism of carbon catabolite repression is discussed.

Comparative Genomics of NAC Transcriptional Factors in Angiosperms: Implications for the Adaptation and Diversification of Flowering Plants

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Pereira-Santana, Alejandro; Alcaraz, Luis David; Castaño, Enrique; Sanchez-Calderon, Lenin; Sanchez-Teyer, Felipe; Rodriguez-Zapata, Luis

2015-01-01

NAC proteins constitute one of the largest groups of plant-specific transcription factors and are known to play essential roles in various developmental processes. They are also important in plant responses to stresses such as drought, soil salinity, cold, and heat, which adversely affect growth. The current knowledge regarding the distribution of NAC proteins in plant lineages comes from relatively small samplings from the available data. In the present study, we broadened the number of plant species containing the NAC family origin and evolution to shed new light on the evolutionary history of this family in angiosperms. A comparative genome analysis was performed on 24 land plant species, and NAC ortholog groups were identified by means of bidirectional BLAST hits. Large NAC gene families are found in those species that have experienced more whole-genome duplication events, pointing to an expansion of the NAC family with divergent functions in flowering plants. A total of 3,187 NAC transcription factors that clustered into six major groups were used in the phylogenetic analysis. Many orthologous groups were found in the monocot and eudicot lineages, but only five orthologous groups were found between P. patens and each representative taxa of flowering plants. These groups were called basal orthologous groups and likely expanded into more recent taxa to cope with their environmental needs. This analysis on the angiosperm NAC family represents an effort to grasp the evolutionary and functional diversity within this gene family while providing a basis for further functional research on vascular plant gene families. PMID:26569117

Comparative Genomics of NAC Transcriptional Factors in Angiosperms: Implications for the Adaptation and Diversification of Flowering Plants.

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Alejandro Pereira-Santana

Full Text Available NAC proteins constitute one of the largest groups of plant-specific transcription factors and are known to play essential roles in various developmental processes. They are also important in plant responses to stresses such as drought, soil salinity, cold, and heat, which adversely affect growth. The current knowledge regarding the distribution of NAC proteins in plant lineages comes from relatively small samplings from the available data. In the present study, we broadened the number of plant species containing the NAC family origin and evolution to shed new light on the evolutionary history of this family in angiosperms. A comparative genome analysis was performed on 24 land plant species, and NAC ortholog groups were identified by means of bidirectional BLAST hits. Large NAC gene families are found in those species that have experienced more whole-genome duplication events, pointing to an expansion of the NAC family with divergent functions in flowering plants. A total of 3,187 NAC transcription factors that clustered into six major groups were used in the phylogenetic analysis. Many orthologous groups were found in the monocot and eudicot lineages, but only five orthologous groups were found between P. patens and each representative taxa of flowering plants. These groups were called basal orthologous groups and likely expanded into more recent taxa to cope with their environmental needs. This analysis on the angiosperm NAC family represents an effort to grasp the evolutionary and functional diversity within this gene family while providing a basis for further functional research on vascular plant gene families.

Evaluating genome-wide DNA methylation changes in mice by Methylation Specific Digital Karyotyping

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Maruoka Shuichiro

2008-12-01

Full Text Available Abstract Background The study of genome-wide DNA methylation changes has become more accessible with the development of various array-based technologies though when studying species other than human the choice of applications are limited and not always within reach. In this study, we adapted and tested the applicability of Methylation Specific Digital Karyotyping (MSDK, a non-array based method, for the prospective analysis of epigenetic changes after perinatal nutritional modifications in a mouse model of allergic airway disease. MSDK is a sequenced based method that allows a comprehensive and unbiased methylation profiling. The method generates 21 base pairs long sequence tags derived from specific locations in the genome. The resulting tag frequencies determine in a quantitative manner the methylation level of the corresponding loci. Results Genomic DNA from whole lung was isolated and subjected to MSDK analysis using the methylation-sensitive enzyme Not I as the mapping enzyme and Nla III as the fragmenting enzyme. In a pair wise comparison of the generated mouse MSDK libraries we identified 158 loci that are significantly differentially methylated (P-value = 0.05 after perinatal dietary changes in our mouse model. Quantitative methylation specific PCR and sequence analysis of bisulfate modified genomic DNA confirmed changes in methylation at specific loci. Differences in genomic MSDK tag counts for a selected set of genes, correlated well with changes in transcription levels as measured by real-time PCR. Furthermore serial analysis of gene expression profiling demonstrated a dramatic difference in expressed transcripts in mice exposed to perinatal nutritional changes. Conclusion The genome-wide methylation survey applied in this study allowed for an unbiased methylation profiling revealing subtle changes in DNA methylation in mice maternally exposed to dietary changes in methyl-donor content. The MSDK method is applicable for mouse models

Comparing genome-wide chromatin profiles using ChIP-chip or ChIP-seq

NARCIS (Netherlands)

Johannes, F.; Wardenaar, R.; Colome-Tatche, M.; Mousson, F.; de Graaf, P.; Mokry, M.; Guryev, V.; Timmers, H.T.; Cuppen, E.; Jansen, R.

2010-01-01

MOTIVATION: ChIP-chip and ChIP-seq technologies provide genome-wide measurements of various types of chromatin marks at an unprecedented resolution. With ChIP samples collected from different tissue types and/or individuals, we can now begin to characterize stochastic or systematic changes in

A hyperactive transcriptional state marks genome reactivation at the mitosis–G1 transition

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Hsiung, Chris C.-S.; Bartman, Caroline R.; Huang, Peng; Ginart, Paul; Stonestrom, Aaron J.; Keller, Cheryl A.; Face, Carolyne; Jahn, Kristen S.; Evans, Perry; Sankaranarayanan, Laavanya; Giardine, Belinda; Hardison, Ross C.; Raj, Arjun; Blobel, Gerd A.

2016-01-01

During mitosis, RNA polymerase II (Pol II) and many transcription factors dissociate from chromatin, and transcription ceases globally. Transcription is known to restart in bulk by telophase, but whether de novo transcription at the mitosis–G1 transition is in any way distinct from later in interphase remains unknown. We tracked Pol II occupancy genome-wide in mammalian cells progressing from mitosis through late G1. Unexpectedly, during the earliest rounds of transcription at the mitosis–G1 transition, ∼50% of active genes and distal enhancers exhibit a spike in transcription, exceeding levels observed later in G1 phase. Enhancer–promoter chromatin contacts are depleted during mitosis and restored rapidly upon G1 entry but do not spike. Of the chromatin-associated features examined, histone H3 Lys27 acetylation levels at individual loci in mitosis best predict the mitosis–G1 transcriptional spike. Single-molecule RNA imaging supports that the mitosis–G1 transcriptional spike can constitute the maximum transcriptional activity per DNA copy throughout the cell division cycle. The transcriptional spike occurs heterogeneously and propagates to cell-to-cell differences in mature mRNA expression. Our results raise the possibility that passage through the mitosis–G1 transition might predispose cells to diverge in gene expression states. PMID:27340175

Combined genome-wide expression profiling and targeted RNA interference in primary mouse macrophages reveals perturbation of transcriptional networks associated with interferon signalling

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Craigon Marie

2009-08-01

Full Text Available Abstract Background Interferons (IFNs are potent antiviral cytokines capable of reprogramming the macrophage phenotype through the induction of interferon-stimulated genes (ISGs. Here we have used targeted RNA interference to suppress the expression of a number of key genes associated with IFN signalling in murine macrophages prior to stimulation with interferon-gamma. Genome-wide changes in transcript abundance caused by siRNA activity were measured using exon-level microarrays in the presence or absence of IFNγ. Results Transfection of murine bone-marrow derived macrophages (BMDMs with a non-targeting (control siRNA and 11 sequence-specific siRNAs was performed using a cationic lipid transfection reagent (Lipofectamine2000 prior to stimulation with IFNγ. Total RNA was harvested from cells and gene expression measured on Affymetrix GeneChip Mouse Exon 1.0 ST Arrays. Network-based analysis of these data revealed six siRNAs to cause a marked shift in the macrophage transcriptome in the presence or absence IFNγ. These six siRNAs targeted the Ifnb1, Irf3, Irf5, Stat1, Stat2 and Nfkb2 transcripts. The perturbation of the transcriptome by the six siRNAs was highly similar in each case and affected the expression of over 600 downstream transcripts. Regulated transcripts were clustered based on co-expression into five major groups corresponding to transcriptional networks associated with the type I and II IFN response, cell cycle regulation, and NF-KB signalling. In addition we have observed a significant non-specific immune stimulation of cells transfected with siRNA using Lipofectamine2000, suggesting use of this reagent in BMDMs, even at low concentrations, is enough to induce a type I IFN response. Conclusion Our results provide evidence that the type I IFN response in murine BMDMs is dependent on Ifnb1, Irf3, Irf5, Stat1, Stat2 and Nfkb2, and that siRNAs targeted to these genes results in perturbation of key transcriptional networks associated

Regulatory hotspots in the malaria parasite genome dictate transcriptional variation.

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Joseph M Gonzales

2008-09-01

Full Text Available The determinants of transcriptional regulation in malaria parasites remain elusive. The presence of a well-characterized gene expression cascade shared by different Plasmodium falciparum strains could imply that transcriptional regulation and its natural variation do not contribute significantly to the evolution of parasite drug resistance. To clarify the role of transcriptional variation as a source of stain-specific diversity in the most deadly malaria species and to find genetic loci that dictate variations in gene expression, we examined genome-wide expression level polymorphisms (ELPs in a genetic cross between phenotypically distinct parasite clones. Significant variation in gene expression is observed through direct co-hybridizations of RNA from different P. falciparum clones. Nearly 18% of genes were regulated by a significant expression quantitative trait locus. The genetic determinants of most of these ELPs resided in hotspots that are physically distant from their targets. The most prominent regulatory locus, influencing 269 transcripts, coincided with a Chromosome 5 amplification event carrying the drug resistance gene, pfmdr1, and 13 other genes. Drug selection pressure in the Dd2 parental clone lineage led not only to a copy number change in the pfmdr1 gene but also to an increased copy number of putative neighboring regulatory factors that, in turn, broadly influence the transcriptional network. Previously unrecognized transcriptional variation, controlled by polymorphic regulatory genes and possibly master regulators within large copy number variants, contributes to sweeping phenotypic evolution in drug-resistant malaria parasites.

Genome-wide transcriptomic responses of the seagrasses Zostera marina and Nanozostera noltii under a simulated heatwave confirm functional types

NARCIS (Netherlands)

Franssen, Susanne U.; Gu, Jenny; Winters, Gidon; Huylmans, Ann-Kathrin; Wienpahl, Isabell; Sparwel, Maximiliane; Coyer, James; Olsen, Jeanine; Reusch, Thorsten; Bornberg-Bauer, Erich

Genome-wide transcription analysis between related species occurring in overlapping ranges can provide insights into the molecular basis underlying different ecological niches. The co-occurring seagrass species, Zostera marina and Nanozostera noltii, are found in marine coastal environments

Genome-wide identification of KANADI1 target genes.

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Paz Merelo

Full Text Available Plant organ development and polarity establishment is mediated by the action of several transcription factors. Among these, the KANADI (KAN subclade of the GARP protein family plays important roles in polarity-associated processes during embryo, shoot and root patterning. In this study, we have identified a set of potential direct target genes of KAN1 through a combination of chromatin immunoprecipitation/DNA sequencing (ChIP-Seq and genome-wide transcriptional profiling using tiling arrays. Target genes are over-represented for genes involved in the regulation of organ development as well as in the response to auxin. KAN1 affects directly the expression of several genes previously shown to be important in the establishment of polarity during lateral organ and vascular tissue development. We also show that KAN1 controls through its target genes auxin effects on organ development at different levels: transport and its regulation, and signaling. In addition, KAN1 regulates genes involved in the response to abscisic acid, jasmonic acid, brassinosteroids, ethylene, cytokinins and gibberellins. The role of KAN1 in organ polarity is antagonized by HD-ZIPIII transcription factors, including REVOLUTA (REV. A comparison of their target genes reveals that the REV/KAN1 module acts in organ patterning through opposite regulation of shared targets. Evidence of mutual repression between closely related family members is also shown.

Genomic selection: genome-wide prediction in plant improvement.

Science.gov (United States)

Desta, Zeratsion Abera; Ortiz, Rodomiro

2014-09-01

Association analysis is used to measure relations between markers and quantitative trait loci (QTL). Their estimation ignores genes with small effects that trigger underpinning quantitative traits. By contrast, genome-wide selection estimates marker effects across the whole genome on the target population based on a prediction model developed in the training population (TP). Whole-genome prediction models estimate all marker effects in all loci and capture small QTL effects. Here, we review several genomic selection (GS) models with respect to both the prediction accuracy and genetic gain from selection. Phenotypic selection or marker-assisted breeding protocols can be replaced by selection, based on whole-genome predictions in which phenotyping updates the model to build up the prediction accuracy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Genome-Wide Comparative Functional Analyses Reveal Adaptations of Salmonella sv. Newport to a Plant Colonization Lifestyle

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Marcos H. de Moraes

2018-05-01

Full Text Available Outbreaks of salmonellosis linked to the consumption of vegetables have been disproportionately associated with strains of serovar Newport. We tested the hypothesis that strains of sv. Newport have evolved unique adaptations to persistence in plants that are not shared by strains of other Salmonella serovars. We used a genome-wide mutant screen to compare growth in tomato fruit of a sv. Newport strain from an outbreak traced to tomatoes, and a sv. Typhimurium strain from animals. Most genes in the sv. Newport strain that were selected during persistence in tomatoes were shared with, and similarly selected in, the sv. Typhimurium strain. Many of their functions are linked to central metabolism, including amino acid biosynthetic pathways, iron acquisition, and maintenance of cell structure. One exception was a greater need for the core genes involved in purine metabolism in sv. Typhimurium than in sv. Newport. We discovered a gene, papA, that was unique to sv. Newport and contributed to the strain’s fitness in tomatoes. The papA gene was present in about 25% of sv. Newport Group III genomes and generally absent from other Salmonella genomes. Homologs of papA were detected in the genomes of Pantoea, Dickeya, and Pectobacterium, members of the Enterobacteriacea family that can colonize both plants and animals.

Targeted genome regulation via synthetic programmable transcriptional regulators

KAUST Repository

Piatek, Agnieszka Anna

2016-04-19

Regulation of gene transcription controls cellular functions and coordinates responses to developmental, physiological and environmental cues. Precise and efficient molecular tools are needed to characterize the functions of single and multiple genes in linear and interacting pathways in a native context. Modular DNA-binding domains from zinc fingers (ZFs) and transcriptional activator-like proteins (TALE) are amenable to bioengineering to bind DNA target sequences of interest. As a result, ZF and TALE proteins were used to develop synthetic programmable transcription factors. However, these systems are limited by the requirement to re-engineer proteins for each new target sequence. The clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR associated 9 (Cas9) genome editing tool was recently repurposed for targeted transcriptional regulation by inactivation of the nuclease activity of Cas9. Due to the facile engineering, simplicity, precision and amenability to library construction, the CRISPR/Cas9 system is poised to revolutionize the functional genomics field across diverse eukaryotic species. In this review, we discuss the development of synthetic customizable transcriptional regulators and provide insights into their current and potential applications, with special emphasis on plant systems, in characterization of gene functions, elucidation of molecular mechanisms and their biotechnological applications. © 2016 Informa UK Limited, trading as Taylor & Francis Group

Genome-wide comparative transcriptome analysis of CMS-D2 and its maintainer and restorer lines in upland cotton.

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Wu, Jianyong; Zhang, Meng; Zhang, Bingbing; Zhang, Xuexian; Guo, Liping; Qi, Tingxiang; Wang, Hailin; Zhang, Jinfa; Xing, Chaozhu

2017-06-08

Cytoplasmic male sterility (CMS) conferred by the cytoplasm from Gossypium harknessii (D2) is an important system for hybrid seed production in Upland cotton (G. hirsutum). The male sterility of CMS-D2 (i.e., A line) can be restored to fertility by a restorer (i.e., R line) carrying the restorer gene Rf1 transferred from the D2 nuclear genome. However, the molecular mechanisms of CMS-D2 and its restoration are poorly understood. In this study, a genome-wide comparative transcriptome analysis was performed to identify differentially expressed genes (DEGs) in flower buds among the isogenic fertile R line and sterile A line derived from a backcross population (BC 8 F 1 ) and the recurrent parent, i.e., the maintainer (B line). A total of 1464 DEGs were identified among the three isogenic lines, and the Rf1-carrying Chr_D05 and its homeologous Chr_A05 had more DEGs than other chromosomes. The results of GO and KEGG enrichment analysis showed differences in circadian rhythm between the fertile and sterile lines. Eleven DEGs were selected for validation using qRT-PCR, confirming the accuracy of the RNA-seq results. Through genome-wide comparative transcriptome analysis, the differential expression profiles of CMS-D2 and its maintainer and restorer lines in Upland cotton were identified. Our results provide an important foundation for further studies into the molecular mechanisms of the interactions between the restorer gene Rf1 and the CMS-D2 cytoplasm.

Coordination of genomic structure and transcription by the main bacterial nucleoid-associated protein HU

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Berger, Michael; Farcas, Anca; Geertz, Marcel; Zhelyazkova, Petya; Brix, Klaudia; Travers, Andrew; Muskhelishvili, Georgi

2010-01-01

The histone-like protein HU is a highly abundant DNA architectural protein that is involved in compacting the DNA of the bacterial nucleoid and in regulating the main DNA transactions, including gene transcription. However, the coordination of the genomic structure and function by HU is poorly understood. Here, we address this question by comparing transcript patterns and spatial distributions of RNA polymerase in Escherichia coli wild-type and hupA/B mutant cells. We demonstrate that, in mutant cells, upregulated genes are preferentially clustered in a large chromosomal domain comprising the ribosomal RNA operons organized on both sides of OriC. Furthermore, we show that, in parallel to this transcription asymmetry, mutant cells are also impaired in forming the transcription foci—spatially confined aggregations of RNA polymerase molecules transcribing strong ribosomal RNA operons. Our data thus implicate HU in coordinating the global genomic structure and function by regulating the spatial distribution of RNA polymerase in the nucleoid. PMID:20010798

Genome-wide conserved non-coding microsatellite (CNMS) marker-based integrative genetical genomics for quantitative dissection of seed weight in chickpea.

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Bajaj, Deepak; Saxena, Maneesha S; Kujur, Alice; Das, Shouvik; Badoni, Saurabh; Tripathi, Shailesh; Upadhyaya, Hari D; Gowda, C L L; Sharma, Shivali; Singh, Sube; Tyagi, Akhilesh K; Parida, Swarup K

2015-03-01

Phylogenetic footprinting identified 666 genome-wide paralogous and orthologous CNMS (conserved non-coding microsatellite) markers from 5'-untranslated and regulatory regions (URRs) of 603 protein-coding chickpea genes. The (CT)n and (GA)n CNMS carrying CTRMCAMV35S and GAGA8BKN3 regulatory elements, respectively, are abundant in the chickpea genome. The mapped genic CNMS markers with robust amplification efficiencies (94.7%) detected higher intraspecific polymorphic potential (37.6%) among genotypes, implying their immense utility in chickpea breeding and genetic analyses. Seventeen differentially expressed CNMS marker-associated genes showing strong preferential and seed tissue/developmental stage-specific expression in contrasting genotypes were selected to narrow down the gene targets underlying seed weight quantitative trait loci (QTLs)/eQTLs (expression QTLs) through integrative genetical genomics. The integration of transcript profiling with seed weight QTL/eQTL mapping, molecular haplotyping, and association analyses identified potential molecular tags (GAGA8BKN3 and RAV1AAT regulatory elements and alleles/haplotypes) in the LOB-domain-containing protein- and KANADI protein-encoding transcription factor genes controlling the cis-regulated expression for seed weight in the chickpea. This emphasizes the potential of CNMS marker-based integrative genetical genomics for the quantitative genetic dissection of complex seed weight in chickpea. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

A genome-wide association study identified AFF1 as a susceptibility locus for systemic lupus eyrthematosus in Japanese.

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Yukinori Okada

2012-01-01

Full Text Available Systemic lupus erythematosus (SLE is an autoimmune disease that causes multiple organ damage. Although recent genome-wide association studies (GWAS have contributed to discovery of SLE susceptibility genes, few studies has been performed in Asian populations. Here, we report a GWAS for SLE examining 891 SLE cases and 3,384 controls and multi-stage replication studies examining 1,387 SLE cases and 28,564 controls in Japanese subjects. Considering that expression quantitative trait loci (eQTLs have been implicated in genetic risks for autoimmune diseases, we integrated an eQTL study into the results of the GWAS. We observed enrichments of cis-eQTL positive loci among the known SLE susceptibility loci (30.8% compared to the genome-wide SNPs (6.9%. In addition, we identified a novel association of a variant in the AF4/FMR2 family, member 1 (AFF1 gene at 4q21 with SLE susceptibility (rs340630; P = 8.3×10(-9, odds ratio = 1.21. The risk A allele of rs340630 demonstrated a cis-eQTL effect on the AFF1 transcript with enhanced expression levels (P<0.05. As AFF1 transcripts were prominently expressed in CD4(+ and CD19(+ peripheral blood lymphocytes, up-regulation of AFF1 may cause the abnormality in these lymphocytes, leading to disease onset.

A genome-wide survey on basic helix-loop-helix transcription factors in giant panda.

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Chunwang Dang

Full Text Available The giant panda (Ailuropoda melanoleuca is a critically endangered mammalian species. Studies on functions of regulatory proteins involved in developmental processes would facilitate understanding of specific behavior in giant panda. The basic helix-loop-helix (bHLH proteins play essential roles in a wide range of developmental processes in higher organisms. bHLH family members have been identified in over 20 organisms, including fruit fly, zebrafish, mouse and human. Our present study identified 107 bHLH family members being encoded in giant panda genome. Phylogenetic analyses revealed that they belong to 44 bHLH families with 46, 25, 15, 4, 11 and 3 members in group A, B, C, D, E and F, respectively, while the remaining 3 members were assigned into "orphan". Compared to mouse, the giant panda does not encode seven bHLH proteins namely Beta3a, Mesp2, Sclerax, S-Myc, Hes5 (or Hes6, EBF4 and Orphan 1. These results provide useful background information for future studies on structure and function of bHLH proteins in the regulation of giant panda development.

Genome-wide identification and characterization of WRKY gene family in peanut

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Hui eSong

2016-04-01

Full Text Available WRKY, an important transcription factor family, is widely distributed in the plant kingdom. Many reports focused on analysis of phylogenetic relationship and biological function of WRKY protein at the whole genome level in different plant species. However, little is known about WRKY proteins in the genome of Arachis species and their response to salicylic acid (SA and jasmonic acid (JA treatment. In this study, we identified 77 and 75 WRKY proteins from the two wild ancestral diploid genomes of cultivated tetraploid peanut, Arachis duranensis and Arachis ipaënsis, using bioinformatics approaches. Most peanut WRKY coding genes were located on A. duranensis chromosome A6 and A. ipaënsis chromosome B3, while the least number of WRKY genes was found in chromosome 9. The WRKY orthologous gene pairs in A. duranensis and A. ipaënsis chromosomes were highly syntenic. Our analysis indicated that segmental duplication events played a major role in AdWRKY and AiWRKY genes, and strong purifying selection was observed in gene duplication pairs. Furthermore, we translate the knowledge gained from the genome-wide analysis result of wild ancestral peanut to cultivated peanut to reveal that gene activities of specific cultivated peanut WRKY gene were changed due to SA and JA treatment. Peanut WRKY7, 8 and 13 genes were down-regulated, whereas WRKY1 and 12 genes were up-regulated with SA and JA treatment. These results could provide valuable information for peanut improvement.

Genome-Wide Identification and Characterization of WRKY Gene Family in Peanut.

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Song, Hui; Wang, Pengfei; Lin, Jer-Young; Zhao, Chuanzhi; Bi, Yuping; Wang, Xingjun

2016-01-01

WRKY, an important transcription factor family, is widely distributed in the plant kingdom. Many reports focused on analysis of phylogenetic relationship and biological function of WRKY protein at the whole genome level in different plant species. However, little is known about WRKY proteins in the genome of Arachis species and their response to salicylic acid (SA) and jasmonic acid (JA) treatment. In this study, we identified 77 and 75 WRKY proteins from the two wild ancestral diploid genomes of cultivated tetraploid peanut, Arachis duranensis and Arachis ipaënsis, using bioinformatics approaches. Most peanut WRKY coding genes were located on A. duranensis chromosome A6 and A. ipaënsis chromosome B3, while the least number of WRKY genes was found in chromosome 9. The WRKY orthologous gene pairs in A. duranensis and A. ipaënsis chromosomes were highly syntenic. Our analysis indicated that segmental duplication events played a major role in AdWRKY and AiWRKY genes, and strong purifying selection was observed in gene duplication pairs. Furthermore, we translate the knowledge gained from the genome-wide analysis result of wild ancestral peanut to cultivated peanut to reveal that gene activities of specific cultivated peanut WRKY gene were changed due to SA and JA treatment. Peanut WRKY7, 8 and 13 genes were down-regulated, whereas WRKY1 and 12 genes were up-regulated with SA and JA treatment. These results could provide valuable information for peanut improvement.

Genome-wide data-mining of candidate human splice translational efficiency polymorphisms (STEPs and an online database.

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Christopher A Raistrick

2010-10-01

Full Text Available Variation in pre-mRNA splicing is common and in some cases caused by genetic variants in intronic splicing motifs. Recent studies into the insulin gene (INS discovered a polymorphism in a 5' non-coding intron that influences the likelihood of intron retention in the final mRNA, extending the 5' untranslated region and maintaining protein quality. Retention was also associated with increased insulin levels, suggesting that such variants--splice translational efficiency polymorphisms (STEPs--may relate to disease phenotypes through differential protein expression. We set out to explore the prevalence of STEPs in the human genome and validate this new category of protein quantitative trait loci (pQTL using publicly available data.Gene transcript and variant data were collected and mined for candidate STEPs in motif regions. Sequences from transcripts containing potential STEPs were analysed for evidence of splice site recognition and an effect in expressed sequence tags (ESTs. 16 publicly released genome-wide association data sets of common diseases were searched for association to candidate polymorphisms with HapMap frequency data. Our study found 3324 candidate STEPs lying in motif sequences of 5' non-coding introns and further mining revealed 170 with transcript evidence of intron retention. 21 potential STEPs had EST evidence of intron retention or exon extension, as well as population frequency data for comparison.Results suggest that the insulin STEP was not a unique example and that many STEPs may occur genome-wide with potentially causal effects in complex disease. An online database of STEPs is freely accessible at http://dbstep.genes.org.uk/.

Comparative genomics of metabolic capacities of regulons controlled by cis-regulatory RNA motifs in bacteria.

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Sun, Eric I; Leyn, Semen A; Kazanov, Marat D; Saier, Milton H; Novichkov, Pavel S; Rodionov, Dmitry A

2013-09-02

In silico comparative genomics approaches have been efficiently used for functional prediction and reconstruction of metabolic and regulatory networks. Riboswitches are metabolite-sensing structures often found in bacterial mRNA leaders controlling gene expression on transcriptional or translational levels.An increasing number of riboswitches and other cis-regulatory RNAs have been recently classified into numerous RNA families in the Rfam database. High conservation of these RNA motifs provides a unique advantage for their genomic identification and comparative analysis. A comparative genomics approach implemented in the RegPredict tool was used for reconstruction and functional annotation of regulons controlled by RNAs from 43 Rfam families in diverse taxonomic groups of Bacteria. The inferred regulons include ~5200 cis-regulatory RNAs and more than 12000 target genes in 255 microbial genomes. All predicted RNA-regulated genes were classified into specific and overall functional categories. Analysis of taxonomic distribution of these categories allowed us to establish major functional preferences for each analyzed cis-regulatory RNA motif family. Overall, most RNA motif regulons showed predictable functional content in accordance with their experimentally established effector ligands. Our results suggest that some RNA motifs (including thiamin pyrophosphate and cobalamin riboswitches that control the cofactor metabolism) are widespread and likely originated from the last common ancestor of all bacteria. However, many more analyzed RNA motifs are restricted to a narrow taxonomic group of bacteria and likely represent more recent evolutionary innovations. The reconstructed regulatory networks for major known RNA motifs substantially expand the existing knowledge of transcriptional regulation in bacteria. The inferred regulons can be used for genetic experiments, functional annotations of genes, metabolic reconstruction and evolutionary analysis. The obtained genome-wide

Genome-wide comparative in silico analysis of the RNA helicase gene family in Zea mays and Glycine max: a comparison with Arabidopsis and Oryza sativa.

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Xu, Ruirui; Zhang, Shizhong; Huang, Jinguang; Zheng, Chengchao

2013-01-01

RNA helicases are enzymes that are thought to unwind double-stranded RNA molecules in an energy-dependent fashion through the hydrolysis of NTP. RNA helicases are associated with all processes involving RNA molecules, including nuclear transcription, editing, splicing, ribosome biogenesis, RNA export, and organelle gene expression. The involvement of RNA helicase in response to stress and in plant growth and development has been reported previously. While their importance in Arabidopsis and Oryza sativa has been partially studied, the function of RNA helicase proteins is poorly understood in Zea mays and Glycine max. In this study, we identified a total of RNA helicase genes in Arabidopsis and other crop species genome by genome-wide comparative in silico analysis. We classified the RNA helicase genes into three subfamilies according to the structural features of the motif II region, such as DEAD-box, DEAH-box and DExD/H-box, and different species showed different patterns of alternative splicing. Secondly, chromosome location analysis showed that the RNA helicase protein genes were distributed across all chromosomes with different densities in the four species. Thirdly, phylogenetic tree analyses identified the relevant homologs of DEAD-box, DEAH-box and DExD/H-box RNA helicase proteins in each of the four species. Fourthly, microarray expression data showed that many of these predicted RNA helicase genes were expressed in different developmental stages and different tissues under normal growth conditions. Finally, real-time quantitative PCR analysis showed that the expression levels of 10 genes in Arabidopsis and 13 genes in Zea mays were in close agreement with the microarray expression data. To our knowledge, this is the first report of a comparative genome-wide analysis of the RNA helicase gene family in Arabidopsis, Oryza sativa, Zea mays and Glycine max. This study provides valuable information for understanding the classification and putative functions of

Transcriptional and Genomic Targets of Neural Stem Cells for Functional Recovery after Hemorrhagic Stroke

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Le Zhang

2017-01-01

Full Text Available Hemorrhagic stroke is a life-threatening disease characterized by a sudden rupture of cerebral blood vessels, and it is widely believed that neural cell death occurs after exposure to blood metabolites or subsequently damaged cells. Neural stem cells (NSCs, which maintain neurogenesis and are found in subgranular zone and subventricular zone, are thought to be an endogenous neuroprotective mechanism for these brain injuries. However, due to the complexity of NSCs and their microenvironment, current strategies cannot satisfactorily enhance functional recovery after hemorrhagic stroke. It is well known that transcriptional and genomic pathways play important roles in ensuring the normal functions of NSCs, including proliferation, migration, differentiation, and neural reconnection. Recently, emerging evidence from the use of new technologies such as next-generation sequencing and transcriptome profiling has provided insight into our understanding of genomic function and regulation of NSCs. In the present article, we summarize and present the current data on the control of NSCs at both the transcriptional and genomic levels. Using bioinformatics methods, we sought to predict novel therapeutic targets of endogenous neurogenesis and exogenous NSC transplantation for functional recovery after hemorrhagic stroke, which could also advance our understanding of its pathophysiology.

Comparison of HapMap and 1000 Genomes Reference Panels in a Large-Scale Genome-Wide Association Study

DEFF Research Database (Denmark)

de Vries, Paul S; Sabater-Lleal, Maria; Chasman, Daniel I

2017-01-01

An increasing number of genome-wide association (GWA) studies are now using the higher resolution 1000 Genomes Project reference panel (1000G) for imputation, with the expectation that 1000G imputation will lead to the discovery of additional associated loci when compared to HapMap imputation. In...

A differential genome-wide transcriptome analysis: impact of cellular copper on complex biological processes like aging and development.

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Jörg Servos

Full Text Available The regulation of cellular copper homeostasis is crucial in biology. Impairments lead to severe dysfunctions and are known to affect aging and development. Previously, a loss-of-function mutation in the gene encoding the copper-sensing and copper-regulated transcription factor GRISEA of the filamentous fungus Podospora anserina was reported to lead to cellular copper depletion and a pleiotropic phenotype with hypopigmentation of the mycelium and the ascospores, affected fertility and increased lifespan by approximately 60% when compared to the wild type. This phenotype is linked to a switch from a copper-dependent standard to an alternative respiration leading to both a reduced generation of reactive oxygen species (ROS and of adenosine triphosphate (ATP. We performed a genome-wide comparative transcriptome analysis of a wild-type strain and the copper-depleted grisea mutant. We unambiguously assigned 9,700 sequences of the transcriptome in both strains to the more than 10,600 predicted and annotated open reading frames of the P. anserina genome indicating 90% coverage of the transcriptome. 4,752 of the transcripts differed significantly in abundance with 1,156 transcripts differing at least 3-fold. Selected genes were investigated by qRT-PCR analyses. Apart from this general characterization we analyzed the data with special emphasis on molecular pathways related to the grisea mutation taking advantage of the available complete genomic sequence of P. anserina. This analysis verified but also corrected conclusions from earlier data obtained by single gene analysis, identified new candidates of factors as part of the cellular copper homeostasis system including target genes of transcription factor GRISEA, and provides a rich reference source of quantitative data for further in detail investigations. Overall, the present study demonstrates the importance of systems biology approaches also in cases were mutations in single genes are analyzed to

Genome-wide screen of ovary-specific DNA methylation in polycystic ovary syndrome.

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Yu, Ying-Ying; Sun, Cui-Xiang; Liu, Yin-Kun; Li, Yan; Wang, Li; Zhang, Wei

2015-07-01

To compare genome-wide DNA methylation profiles in ovary tissue from women with polycystic ovary syndrome (PCOS) and healthy controls. Case-control study matched for age and body mass index. University-affiliated hospital. Ten women with PCOS who underwent ovarian drilling to induce ovulation and 10 healthy women who were undergoing laparoscopic sterilization, hysterectomy for benign conditions, diagnostic laparoscopy for pelvic pain, or oophorectomy for nonovarian indications. None. Genome-wide DNA methylation patterns determined by immunoprecipitation and microarray (MeDIP-chip) analysis. The methylation levels were statistically significantly higher in CpG island shores (CGI shores), which lie outside of core promoter regions, and lower within gene bodies in women with PCOS relative to the controls. In addition, high CpG content promoters were the most frequently hypermethylated promoters in PCOS ovaries but were more often hypomethylated in controls. Second, 872 CGIs, specifically methylated in PCOS, represented 342 genes that could be associated with various molecular functions, including protein binding, hormone activity, and transcription regulator activity. Finally, methylation differences were validated in seven genes by methylation-specific polymerase chain reaction. These genes correlated to several functional families related to the pathogenesis of PCOS and may be potential biomarkers for this disease. Our results demonstrated that epigenetic modification differs between PCOS and normal ovaries, which may help to further understand the pathophysiology of this disease. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Multi-targeted priming for genome-wide gene expression assays

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Adomas Aleksandra B

2010-08-01

Full Text Available Abstract Background Complementary approaches to assaying global gene expression are needed to assess gene expression in regions that are poorly assayed by current methodologies. A key component of nearly all gene expression assays is the reverse transcription of transcribed sequences that has traditionally been performed by priming the poly-A tails on many of the transcribed genes in eukaryotes with oligo-dT, or by priming RNA indiscriminately with random hexamers. We designed an algorithm to find common sequence motifs that were present within most protein-coding genes of Saccharomyces cerevisiae and of Neurospora crassa, but that were not present within their ribosomal RNA or transfer RNA genes. We then experimentally tested whether degenerately priming these motifs with multi-targeted primers improved the accuracy and completeness of transcriptomic assays. Results We discovered two multi-targeted primers that would prime a preponderance of genes in the genomes of Saccharomyces cerevisiae and Neurospora crassa while avoiding priming ribosomal RNA or transfer RNA. Examining the response of Saccharomyces cerevisiae to nitrogen deficiency and profiling Neurospora crassa early sexual development, we demonstrated that using multi-targeted primers in reverse transcription led to superior performance of microarray profiling and next-generation RNA tag sequencing. Priming with multi-targeted primers in addition to oligo-dT resulted in higher sensitivity, a larger number of well-measured genes and greater power to detect differences in gene expression. Conclusions Our results provide the most complete and detailed expression profiles of the yeast nitrogen starvation response and N. crassa early sexual development to date. Furthermore, our multi-targeting priming methodology for genome-wide gene expression assays provides selective targeting of multiple sequences and counter-selection against undesirable sequences, facilitating a more complete and

A hyperactive transcriptional state marks genome reactivation at the mitosis-G1 transition.

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Hsiung, Chris C-S; Bartman, Caroline R; Huang, Peng; Ginart, Paul; Stonestrom, Aaron J; Keller, Cheryl A; Face, Carolyne; Jahn, Kristen S; Evans, Perry; Sankaranarayanan, Laavanya; Giardine, Belinda; Hardison, Ross C; Raj, Arjun; Blobel, Gerd A

2016-06-15

During mitosis, RNA polymerase II (Pol II) and many transcription factors dissociate from chromatin, and transcription ceases globally. Transcription is known to restart in bulk by telophase, but whether de novo transcription at the mitosis-G1 transition is in any way distinct from later in interphase remains unknown. We tracked Pol II occupancy genome-wide in mammalian cells progressing from mitosis through late G1. Unexpectedly, during the earliest rounds of transcription at the mitosis-G1 transition, ∼50% of active genes and distal enhancers exhibit a spike in transcription, exceeding levels observed later in G1 phase. Enhancer-promoter chromatin contacts are depleted during mitosis and restored rapidly upon G1 entry but do not spike. Of the chromatin-associated features examined, histone H3 Lys27 acetylation levels at individual loci in mitosis best predict the mitosis-G1 transcriptional spike. Single-molecule RNA imaging supports that the mitosis-G1 transcriptional spike can constitute the maximum transcriptional activity per DNA copy throughout the cell division cycle. The transcriptional spike occurs heterogeneously and propagates to cell-to-cell differences in mature mRNA expression. Our results raise the possibility that passage through the mitosis-G1 transition might predispose cells to diverge in gene expression states. © 2016 Hsiung et al.; Published by Cold Spring Harbor Laboratory Press.

New families of human regulatory RNA structures identified by comparative analysis of vertebrate genomes.

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Parker, Brian J; Moltke, Ida; Roth, Adam; Washietl, Stefan; Wen, Jiayu; Kellis, Manolis; Breaker, Ronald; Pedersen, Jakob Skou

2011-11-01

Regulatory RNA structures are often members of families with multiple paralogous instances across the genome. Family members share functional and structural properties, which allow them to be studied as a whole, facilitating both bioinformatic and experimental characterization. We have developed a comparative method, EvoFam, for genome-wide identification of families of regulatory RNA structures, based on primary sequence and secondary structure similarity. We apply EvoFam to a 41-way genomic vertebrate alignment. Genome-wide, we identify 220 human, high-confidence families outside protein-coding regions comprising 725 individual structures, including 48 families with known structural RNA elements. Known families identified include both noncoding RNAs, e.g., miRNAs and the recently identified MALAT1/MEN β lincRNA family; and cis-regulatory structures, e.g., iron-responsive elements. We also identify tens of new families supported by strong evolutionary evidence and other statistical evidence, such as GO term enrichments. For some of these, detailed analysis has led to the formulation of specific functional hypotheses. Examples include two hypothesized auto-regulatory feedback mechanisms: one involving six long hairpins in the 3'-UTR of MAT2A, a key metabolic gene that produces the primary human methyl donor S-adenosylmethionine; the other involving a tRNA-like structure in the intron of the tRNA maturation gene POP1. We experimentally validate the predicted MAT2A structures. Finally, we identify potential new regulatory networks, including large families of short hairpins enriched in immunity-related genes, e.g., TNF, FOS, and CTLA4, which include known transcript destabilizing elements. Our findings exemplify the diversity of post-transcriptional regulation and provide a resource for further characterization of new regulatory mechanisms and families of noncoding RNAs.

Correlation of microRNA levels during hypoxia with predicted target mRNAs through genome-wide microarray analysis

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Page Grier P

2009-03-01

Full Text Available Abstract Background Low levels of oxygen in tissues, seen in situations such as chronic lung disease, necrotic tumors, and high altitude exposures, initiate a signaling pathway that results in active transcription of genes possessing a hypoxia response element (HRE. The aim of this study was to investigate whether a change in miRNA expression following hypoxia could account for changes in the cellular transcriptome based on currently available miRNA target prediction tools. Methods To identify changes induced by hypoxia, we conducted mRNA- and miRNA-array-based experiments in HT29 cells, and performed comparative analysis of the resulting data sets based on multiple target prediction algorithms. To date, few studies have investigated an environmental perturbation for effects on genome-wide miRNA levels, or their consequent influence on mRNA output. Results Comparison of miRNAs with predicted mRNA targets indicated a lower level of concordance than expected. We did, however, find preliminary evidence of combinatorial regulation of mRNA expression by miRNA. Conclusion Target prediction programs and expression profiling techniques do not yet adequately represent the complexity of miRNA-mediated gene repression, and new methods may be required to better elucidate these pathways. Our data suggest the physiologic impact of miRNAs on cellular transcription results from a multifaceted network of miRNA and mRNA relationships, working together in an interconnected system and in context of hundreds of RNA species. The methods described here for comparative analysis of cellular miRNA and mRNA will be useful for understanding genome wide regulatory responsiveness and refining miRNA predictive algorithms.

Vitamin D receptor signaling and its therapeutic implications: Genome-wide and structural view.

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Carlberg, Carsten; Molnár, Ferdinand

2015-05-01

Vitamin D3 is one of the few natural compounds that has, via its metabolite 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) and the transcription factor vitamin D receptor (VDR), a direct effect on gene regulation. For efficiently applying the therapeutic and disease-preventing potential of 1,25(OH)2D3 and its synthetic analogs, the key steps in vitamin D signaling need to be understood. These are the different types of molecular interactions with the VDR, such as (i) the complex formation of VDR with genomic DNA, (ii) the interaction of VDR with its partner transcription factors, (iii) the binding of 1,25(OH)2D3 or its synthetic analogs within the ligand-binding pocket of the VDR, and (iv) the resulting conformational change on the surface of the VDR leading to a change of the protein-protein interaction profile of the receptor with other proteins. This review will present the latest genome-wide insight into vitamin D signaling, and will discuss its therapeutic implications.

Effects of in ovo electroporation on endogenous gene expression: genome-wide analysis

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Chambers David

2011-04-01

Full Text Available Abstract Background In ovo electroporation is a widely used technique to study gene function in developmental biology. Despite the widespread acceptance of this technique, no genome-wide analysis of the effects of in ovo electroporation, principally the current applied across the tissue and exogenous vector DNA introduced, on endogenous gene expression has been undertaken. Here, the effects of electric current and expression of a GFP-containing construct, via electroporation into the midbrain of Hamburger-Hamilton stage 10 chicken embryos, are analysed by microarray. Results Both current alone and in combination with exogenous DNA expression have a small but reproducible effect on endogenous gene expression, changing the expression of the genes represented on the array by less than 0.1% (current and less than 0.5% (current + DNA, respectively. The subset of genes regulated by electric current and exogenous DNA span a disparate set of cellular functions. However, no genes involved in the regional identity were affected. In sharp contrast to this, electroporation of a known transcription factor, Dmrt5, caused a much greater change in gene expression. Conclusions These findings represent the first systematic genome-wide analysis of the effects of in ovo electroporation on gene expression during embryonic development. The analysis reveals that this process has minimal impact on the genetic basis of cell fate specification. Thus, the study demonstrates the validity of the in ovo electroporation technique to study gene function and expression during development. Furthermore, the data presented here can be used as a resource to refine the set of transcriptional responders in future in ovo electroporation studies of specific gene function.

GWAMA: software for genome-wide association meta-analysis

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Mägi Reedik

2010-05-01

Full Text Available Abstract Background Despite the recent success of genome-wide association studies in identifying novel loci contributing effects to complex human traits, such as type 2 diabetes and obesity, much of the genetic component of variation in these phenotypes remains unexplained. One way to improving power to detect further novel loci is through meta-analysis of studies from the same population, increasing the sample size over any individual study. Although statistical software analysis packages incorporate routines for meta-analysis, they are ill equipped to meet the challenges of the scale and complexity of data generated in genome-wide association studies. Results We have developed flexible, open-source software for the meta-analysis of genome-wide association studies. The software incorporates a variety of error trapping facilities, and provides a range of meta-analysis summary statistics. The software is distributed with scripts that allow simple formatting of files containing the results of each association study and generate graphical summaries of genome-wide meta-analysis results. Conclusions The GWAMA (Genome-Wide Association Meta-Analysis software has been developed to perform meta-analysis of summary statistics generated from genome-wide association studies of dichotomous phenotypes or quantitative traits. Software with source files, documentation and example data files are freely available online at http://www.well.ox.ac.uk/GWAMA.

Whole genome transcription profiling of Anaplasma phagocytophilum in human and tick host cells by tiling array analysis

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Chavez Adela

2008-07-01

Full Text Available Abstract Background Anaplasma phagocytophilum (Ap is an obligate intracellular bacterium and the agent of human granulocytic anaplasmosis, an emerging tick-borne disease. Ap alternately infects ticks and mammals and a variety of cell types within each. Understanding the biology behind such versatile cellular parasitism may be derived through the use of tiling microarrays to establish high resolution, genome-wide transcription profiles of the organism as it infects cell lines representative of its life cycle (tick; ISE6 and pathogenesis (human; HL-60 and HMEC-1. Results Detailed, host cell specific transcriptional behavior was revealed. There was extensive differential Ap gene transcription between the tick (ISE6 and the human (HL-60 and HMEC-1 cell lines, with far fewer differentially transcribed genes between the human cell lines, and all disproportionately represented by membrane or surface proteins. There were Ap genes exclusively transcribed in each cell line, apparent human- and tick-specific operons and paralogs, and anti-sense transcripts that suggest novel expression regulation processes. Seven virB2 paralogs (of the bacterial type IV secretion system showed human or tick cell dependent transcription. Previously unrecognized genes and coding sequences were identified, as were the expressed p44/msp2 (major surface proteins paralogs (of 114 total, through elevated signal produced to the unique hypervariable region of each – 2/114 in HL-60, 3/114 in HMEC-1, and none in ISE6. Conclusion Using these methods, whole genome transcription profiles can likely be generated for Ap, as well as other obligate intracellular organisms, in any host cells and for all stages of the cell infection process. Visual representation of comprehensive transcription data alongside an annotated map of the genome renders complex transcription into discernable patterns.

Genome-wide transcriptional response of Silurana (Xenopus tropicalis to infection with the deadly chytrid fungus.

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Erica Bree Rosenblum

Full Text Available Emerging infectious diseases are of great concern for both wildlife and humans. Several highly virulent fungal pathogens have recently been discovered in natural populations, highlighting the need for a better understanding of fungal-vertebrate host-pathogen interactions. Because most fungal pathogens are not fatal in the absence of other predisposing conditions, host-pathogen dynamics for deadly fungal pathogens are of particular interest. The chytrid fungus Batrachochytrium dendrobatidis (hereafter Bd infects hundreds of species of frogs in the wild. It is found worldwide and is a significant contributor to the current global amphibian decline. However, the mechanism by which Bd causes death in amphibians, and the response of the host to Bd infection, remain largely unknown. Here we use whole-genome microarrays to monitor the transcriptional responses to Bd infection in the model frog species, Silurana (Xenopus tropicalis, which is susceptible to chytridiomycosis. To elucidate the immune response to Bd and evaluate the physiological effects of chytridiomycosis, we measured gene expression changes in several tissues (liver, skin, spleen following exposure to Bd. We detected a strong transcriptional response for genes involved in physiological processes that can help explain some clinical symptoms of chytridiomycosis at the organismal level. However, we detected surprisingly little evidence of an immune response to Bd exposure, suggesting that this susceptible species may not be mounting efficient innate and adaptive immune responses against Bd. The weak immune response may be partially explained by the thermal conditions of the experiment, which were optimal for Bd growth. However, many immune genes exhibited decreased expression in Bd-exposed frogs compared to control frogs, suggesting a more complex effect of Bd on the immune system than simple temperature-mediated immune suppression. This study generates important baseline data for ongoing

Genome-Wide Identification and Expression Analysis of WRKY Gene Family in Capsicum annuum L.

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Diao, Wei-Ping; Snyder, John C; Wang, Shu-Bin; Liu, Jin-Bing; Pan, Bao-Gui; Guo, Guang-Jun; Wei, Ge

2016-01-01

The WRKY family of transcription factors is one of the most important families of plant transcriptional regulators with members regulating multiple biological processes, especially in regulating defense against biotic and abiotic stresses. However, little information is available about WRKYs in pepper (Capsicum annuum L.). The recent release of completely assembled genome sequences of pepper allowed us to perform a genome-wide investigation for pepper WRKY proteins. In the present study, a total of 71 WRKY genes were identified in the pepper genome. According to structural features of their encoded proteins, the pepper WRKY genes (CaWRKY) were classified into three main groups, with the second group further divided into five subgroups. Genome mapping analysis revealed that CaWRKY were enriched on four chromosomes, especially on chromosome 1, and 15.5% of the family members were tandemly duplicated genes. A phylogenetic tree was constructed depending on WRKY domain' sequences derived from pepper and Arabidopsis. The expression of 21 selected CaWRKY genes in response to seven different biotic and abiotic stresses (salt, heat shock, drought, Phytophtora capsici, SA, MeJA, and ABA) was evaluated by quantitative RT-PCR; Some CaWRKYs were highly expressed and up-regulated by stress treatment. Our results will provide a platform for functional identification and molecular breeding studies of WRKY genes in pepper.

Zipper plot: visualizing transcriptional activity of genomic regions.

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Avila Cobos, Francisco; Anckaert, Jasper; Volders, Pieter-Jan; Everaert, Celine; Rombaut, Dries; Vandesompele, Jo; De Preter, Katleen; Mestdagh, Pieter

2017-05-02

Reconstructing transcript models from RNA-sequencing (RNA-seq) data and establishing these as independent transcriptional units can be a challenging task. Current state-of-the-art tools for long non-coding RNA (lncRNA) annotation are mainly based on evolutionary constraints, which may result in false negatives due to the overall limited conservation of lncRNAs. To tackle this problem we have developed the Zipper plot, a novel visualization and analysis method that enables users to simultaneously interrogate thousands of human putative transcription start sites (TSSs) in relation to various features that are indicative for transcriptional activity. These include publicly available CAGE-sequencing, ChIP-sequencing and DNase-sequencing datasets. Our method only requires three tab-separated fields (chromosome, genomic coordinate of the TSS and strand) as input and generates a report that includes a detailed summary table, a Zipper plot and several statistics derived from this plot. Using the Zipper plot, we found evidence of transcription for a set of well-characterized lncRNAs and observed that fewer mono-exonic lncRNAs have CAGE peaks overlapping with their TSSs compared to multi-exonic lncRNAs. Using publicly available RNA-seq data, we found more than one hundred cases where junction reads connected protein-coding gene exons with a downstream mono-exonic lncRNA, revealing the need for a careful evaluation of lncRNA 5'-boundaries. Our method is implemented using the statistical programming language R and is freely available as a webtool.

Genome-wide investigation and expression profiling of AP2/ERF transcription factor superfamily in foxtail millet (Setaria italica L.).

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Lata, Charu; Mishra, Awdhesh Kumar; Muthamilarasan, Mehanathan; Bonthala, Venkata Suresh; Khan, Yusuf; Prasad, Manoj

2014-01-01

The APETALA2/ethylene-responsive element binding factor (AP2/ERF) family is one of the largest transcription factor (TF) families in plants that includes four major sub-families, namely AP2, DREB (dehydration responsive element binding), ERF (ethylene responsive factors) and RAV (Related to ABI3/VP). AP2/ERFs are known to play significant roles in various plant processes including growth and development and biotic and abiotic stress responses. Considering this, a comprehensive genome-wide study was conducted in foxtail millet (Setaria italica L.). A total of 171 AP2/ERF genes were identified by systematic sequence analysis and were physically mapped onto nine chromosomes. Phylogenetic analysis grouped AP2/ERF genes into six classes (I to VI). Duplication analysis revealed that 12 (∼7%) SiAP2/ERF genes were tandem repeated and 22 (∼13%) were segmentally duplicated. Comparative physical mapping between foxtail millet AP2/ERF genes and its orthologs of sorghum (18 genes), maize (14 genes), rice (9 genes) and Brachypodium (6 genes) showed the evolutionary insights of AP2/ERF gene family and also the decrease in orthology with increase in phylogenetic distance. The evolutionary significance in terms of gene-duplication and divergence was analyzed by estimating synonymous and non-synonymous substitution rates. Expression profiling of candidate AP2/ERF genes against drought, salt and phytohormones revealed insights into their precise and/or overlapping expression patterns which could be responsible for their functional divergence in foxtail millet. The study showed that the genes SiAP2/ERF-069, SiAP2/ERF-103 and SiAP2/ERF-120 may be considered as potential candidate genes for further functional validation as well for utilization in crop improvement programs for stress resistance since these genes were up-regulated under drought and salinity stresses in ABA dependent manner. Altogether the present study provides new insights into evolution, divergence and systematic

Genome-wide investigation and expression profiling of AP2/ERF transcription factor superfamily in foxtail millet (Setaria italica L..

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Charu Lata

Full Text Available The APETALA2/ethylene-responsive element binding factor (AP2/ERF family is one of the largest transcription factor (TF families in plants that includes four major sub-families, namely AP2, DREB (dehydration responsive element binding, ERF (ethylene responsive factors and RAV (Related to ABI3/VP. AP2/ERFs are known to play significant roles in various plant processes including growth and development and biotic and abiotic stress responses. Considering this, a comprehensive genome-wide study was conducted in foxtail millet (Setaria italica L.. A total of 171 AP2/ERF genes were identified by systematic sequence analysis and were physically mapped onto nine chromosomes. Phylogenetic analysis grouped AP2/ERF genes into six classes (I to VI. Duplication analysis revealed that 12 (∼7% SiAP2/ERF genes were tandem repeated and 22 (∼13% were segmentally duplicated. Comparative physical mapping between foxtail millet AP2/ERF genes and its orthologs of sorghum (18 genes, maize (14 genes, rice (9 genes and Brachypodium (6 genes showed the evolutionary insights of AP2/ERF gene family and also the decrease in orthology with increase in phylogenetic distance. The evolutionary significance in terms of gene-duplication and divergence was analyzed by estimating synonymous and non-synonymous substitution rates. Expression profiling of candidate AP2/ERF genes against drought, salt and phytohormones revealed insights into their precise and/or overlapping expression patterns which could be responsible for their functional divergence in foxtail millet. The study showed that the genes SiAP2/ERF-069, SiAP2/ERF-103 and SiAP2/ERF-120 may be considered as potential candidate genes for further functional validation as well for utilization in crop improvement programs for stress resistance since these genes were up-regulated under drought and salinity stresses in ABA dependent manner. Altogether the present study provides new insights into evolution, divergence and

Genome-wide function of H2B ubiquitylation in promoter and genic regions.

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Batta, Kiran; Zhang, Zhenhai; Yen, Kuangyu; Goffman, David B; Pugh, B Franklin

2011-11-01

Nucleosomal organization in and around genes may contribute substantially to transcriptional regulation. The contribution of histone modifications to genome-wide nucleosomal organization has not been systematically evaluated. In the present study, we examine the role of H2BK123 ubiquitylation, a key regulator of several histone modifications, on nucleosomal organization at promoter, genic, and transcription termination regions in Saccharomyces cerevisiae. Using high-resolution MNase chromatin immunoprecipitation and sequencing (ChIP-seq), we map nucleosome positioning and occupancy in mutants of the H2BK123 ubiquitylation pathway. We found that H2B ubiquitylation-mediated nucleosome formation and/or stability inhibits the assembly of the transcription machinery at normally quiescent promoters, whereas ubiquitylation within highly active gene bodies promotes transcription elongation. This regulation does not proceed through ubiquitylation-regulated histone marks at H3K4, K36, and K79. Our findings suggest that mechanistically similar functions of H2B ubiquitylation (nucleosome assembly) elicit different functional outcomes on genes depending on its positional context in promoters (repressive) versus transcribed regions (activating).

Genome Binding and Gene Regulation by Stem Cell Transcription Factors

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J.H. Brandsma (Johan)

2016-01-01

markdownabstractNearly all cells of an individual organism contain the same genome. However, each cell type transcribes a different set of genes due to the presence of different sets of cell type-specific transcription factors. Such transcription factors bind to regulatory regions such as promoters

Comparative genomics and stx phage characterization of LEE-negative Shiga toxin-producing Escherichia coli

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Susan Renee Steyert

2012-11-01

Full Text Available Infection by Escherichia coli and Shigella species are among the leading causes of death due to diarrheal disease in the world. Shiga toxin producing Escherichia coli (STEC that do not encode the locus of enterocyte effacement (LEE-negative STEC often possess Shiga toxin gene variants and have been isolated from humans and a variety of animal sources. In this study, we compare the genomes of nine LEE-negative STEC harboring various stx alleles with four complete reference LEE-positive STEC isolates. Compared to a representative collection of prototype E. coli and Shigella isolates representing each of the pathotypes, the whole genome phylogeny demonstrated that these isolates are diverse. Whole genome comparative analysis of the 13 genomes revealed that in addition to the absence of the LEE pathogenicity island, phage encoded genes including non-LEE encoded effectors, were absent from all nine LEE-negative STEC genomes. Several plasmid-encoded virulence factors reportedly identified in LEE-negative STEC isolates were identified in only a subset of the nine LEE-negative isolates further confirming the diversity of this group. In combination with whole genome analysis, we characterized the lambdoid phages harboring the various stx alleles and determined their genomic insertion sites. Although the integrase gene sequence corresponded with genomic location, it was not correlated with stx variant, further highlighting the mosaic nature of these phages. The transcription of these phages in different genomic backgrounds was examined. Expression of the Shiga toxin genes, stx1 and/or stx2, as well as the Q genes, were examined with quantitative reverse transcriptase polymerase chain reaction (qRT-PCR assays. A wide range of basal and induced toxin induction was observed. Overall, this is a first significant foray into the genome space of this unexplored group of emerging and divergent pathogens.

Gramene database: Navigating plant comparative genomics resources

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Parul Gupta

2016-11-01

Full Text Available Gramene (http://www.gramene.org is an online, open source, curated resource for plant comparative genomics and pathway analysis designed to support researchers working in plant genomics, breeding, evolutionary biology, system biology, and metabolic engineering. It exploits phylogenetic relationships to enrich the annotation of genomic data and provides tools to perform powerful comparative analyses across a wide spectrum of plant species. It consists of an integrated portal for querying, visualizing and analyzing data for 44 plant reference genomes, genetic variation data sets for 12 species, expression data for 16 species, curated rice pathways and orthology-based pathway projections for 66 plant species including various crops. Here we briefly describe the functions and uses of the Gramene database.

RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome

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Dewey Colin N

2011-08-01

Full Text Available Abstract Background RNA-Seq is revolutionizing the way transcript abundances are measured. A key challenge in transcript quantification from RNA-Seq data is the handling of reads that map to multiple genes or isoforms. This issue is particularly important for quantification with de novo transcriptome assemblies in the absence of sequenced genomes, as it is difficult to determine which transcripts are isoforms of the same gene. A second significant issue is the design of RNA-Seq experiments, in terms of the number of reads, read length, and whether reads come from one or both ends of cDNA fragments. Results We present RSEM, an user-friendly software package for quantifying gene and isoform abundances from single-end or paired-end RNA-Seq data. RSEM outputs abundance estimates, 95% credibility intervals, and visualization files and can also simulate RNA-Seq data. In contrast to other existing tools, the software does not require a reference genome. Thus, in combination with a de novo transcriptome assembler, RSEM enables accurate transcript quantification for species without sequenced genomes. On simulated and real data sets, RSEM has superior or comparable performance to quantification methods that rely on a reference genome. Taking advantage of RSEM's ability to effectively use ambiguously-mapping reads, we show that accurate gene-level abundance estimates are best obtained with large numbers of short single-end reads. On the other hand, estimates of the relative frequencies of isoforms within single genes may be improved through the use of paired-end reads, depending on the number of possible splice forms for each gene. Conclusions RSEM is an accurate and user-friendly software tool for quantifying transcript abundances from RNA-Seq data. As it does not rely on the existence of a reference genome, it is particularly useful for quantification with de novo transcriptome assemblies. In addition, RSEM has enabled valuable guidance for cost

Comparing Mycobacterium tuberculosis genomes using genome topology networks.

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Jiang, Jianping; Gu, Jianlei; Zhang, Liang; Zhang, Chenyi; Deng, Xiao; Dou, Tonghai; Zhao, Guoping; Zhou, Yan

2015-02-14

Over the last decade, emerging research methods, such as comparative genomic analysis and phylogenetic study, have yielded new insights into genotypes and phenotypes of closely related bacterial strains. Several findings have revealed that genomic structural variations (SVs), including gene gain/loss, gene duplication and genome rearrangement, can lead to different phenotypes among strains, and an investigation of genes affected by SVs may extend our knowledge of the relationships between SVs and phenotypes in microbes, especially in pathogenic bacteria. In this work, we introduce a 'Genome Topology Network' (GTN) method based on gene homology and gene locations to analyze genomic SVs and perform phylogenetic analysis. Furthermore, the concept of 'unfixed ortholog' has been proposed, whose members are affected by SVs in genome topology among close species. To improve the precision of 'unfixed ortholog' recognition, a strategy to detect annotation differences and complete gene annotation was applied. To assess the GTN method, a set of thirteen complete M. tuberculosis genomes was analyzed as a case study. GTNs with two different gene homology-assigning methods were built, the Clusters of Orthologous Groups (COG) method and the orthoMCL clustering method, and two phylogenetic trees were constructed accordingly, which may provide additional insights into whole genome-based phylogenetic analysis. We obtained 24 unfixable COG groups, of which most members were related to immunogenicity and drug resistance, such as PPE-repeat proteins (COG5651) and transcriptional regulator TetR gene family members (COG1309). The GTN method has been implemented in PERL and released on our website. The tool can be downloaded from http://homepage.fudan.edu.cn/zhouyan/gtn/ , and allows re-annotating the 'lost' genes among closely related genomes, analyzing genes affected by SVs, and performing phylogenetic analysis. With this tool, many immunogenic-related and drug resistance-related genes

Genome-wide DNA polymorphism analyses using VariScan

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Vilella Albert J

2006-09-01

Full Text Available Abstract Background DNA sequence polymorphisms analysis can provide valuable information on the evolutionary forces shaping nucleotide variation, and provides an insight into the functional significance of genomic regions. The recent ongoing genome projects will radically improve our capabilities to detect specific genomic regions shaped by natural selection. Current available methods and software, however, are unsatisfactory for such genome-wide analysis. Results We have developed methods for the analysis of DNA sequence polymorphisms at the genome-wide scale. These methods, which have been tested on a coalescent-simulated and actual data files from mouse and human, have been implemented in the VariScan software package version 2.0. Additionally, we have also incorporated a graphical-user interface. The main features of this software are: i exhaustive population-genetic analyses including those based on the coalescent theory; ii analysis adapted to the shallow data generated by the high-throughput genome projects; iii use of genome annotations to conduct a comprehensive analyses separately for different functional regions; iv identification of relevant genomic regions by the sliding-window and wavelet-multiresolution approaches; v visualization of the results integrated with current genome annotations in commonly available genome browsers. Conclusion VariScan is a powerful and flexible suite of software for the analysis of DNA polymorphisms. The current version implements new algorithms, methods, and capabilities, providing an important tool for an exhaustive exploratory analysis of genome-wide DNA polymorphism data.

A novel statistic for genome-wide interaction analysis.

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Xuesen Wu

2010-09-01

Full Text Available Although great progress in genome-wide association studies (GWAS has been made, the significant SNP associations identified by GWAS account for only a few percent of the genetic variance, leading many to question where and how we can find the missing heritability. There is increasing interest in genome-wide interaction analysis as a possible source of finding heritability unexplained by current GWAS. However, the existing statistics for testing interaction have low power for genome-wide interaction analysis. To meet challenges raised by genome-wide interactional analysis, we have developed a novel statistic for testing interaction between two loci (either linked or unlinked. The null distribution and the type I error rates of the new statistic for testing interaction are validated using simulations. Extensive power studies show that the developed statistic has much higher power to detect interaction than classical logistic regression. The results identified 44 and 211 pairs of SNPs showing significant evidence of interactions with FDR<0.001 and 0.001genome-wide interaction analysis is a valuable tool for finding remaining missing heritability unexplained by the current GWAS, and the developed novel statistic is able to search significant interaction between SNPs across the genome. Real data analysis showed that the results of genome-wide interaction analysis can be replicated in two independent studies.

Genome-wide development and deployment of informative intron-spanning and intron-length polymorphism markers for genomics-assisted breeding applications in chickpea.

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Srivastava, Rishi; Bajaj, Deepak; Sayal, Yogesh K; Meher, Prabina K; Upadhyaya, Hari D; Kumar, Rajendra; Tripathi, Shailesh; Bharadwaj, Chellapilla; Rao, Atmakuri R; Parida, Swarup K

2016-11-01

The discovery and large-scale genotyping of informative gene-based markers is essential for rapid delineation of genes/QTLs governing stress tolerance and yield component traits in order to drive genetic enhancement in chickpea. A genome-wide 119169 and 110491 ISM (intron-spanning markers) from 23129 desi and 20386 kabuli protein-coding genes and 7454 in silico InDel (insertion-deletion) (1-45-bp)-based ILP (intron-length polymorphism) markers from 3283 genes were developed that were structurally and functionally annotated on eight chromosomes and unanchored scaffolds of chickpea. A much higher amplification efficiency (83%) and intra-specific polymorphic potential (86%) detected by these markers than that of other sequence-based genetic markers among desi and kabuli chickpea accessions was apparent even by a cost-effective agarose gel-based assay. The genome-wide physically mapped 1718 ILP markers assayed a wider level of functional genetic diversity (19-81%) and well-defined phylogenetics among domesticated chickpea accessions. The gene-derived 1424 ILP markers were anchored on a high-density (inter-marker distance: 0.65cM) desi intra-specific genetic linkage map/functional transcript map (ICC 4958×ICC 2263) of chickpea. This reference genetic map identified six major genomic regions harbouring six robust QTLs mapped on five chromosomes, which explained 11-23% seed weight trait variation (7.6-10.5 LOD) in chickpea. The integration of high-resolution QTL mapping with differential expression profiling detected six including one potential serine carboxypeptidase gene with ILP markers (linked tightly to the major seed weight QTLs) exhibiting seed-specific expression as well as pronounced up-regulation especially in seeds of high (ICC 4958) as compared to low (ICC 2263) seed weight mapping parental accessions. The marker information generated in the present study was made publicly accessible through a user-friendly web-resource, "Chickpea ISM-ILP Marker Database

Identification of genome-specific transcripts in wheat–rye translocation lines

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Tong Geon Lee

2015-09-01

Full Text Available Studying gene expression in wheat–rye translocation lines is complicated due to the presence of homeologs in hexaploid wheat and high levels of synteny between wheat and rye genomes (Naranjo and Fernandez-Rueda, 1991 [1]; Devos et al., 1995 [2]; Lee et al., 2010 [3]; Lee et al., 2013 [4]. To overcome limitations of current gene expression studies on wheat–rye translocation lines and identify genome-specific transcripts, we developed a custom Roche NimbleGen Gene Expression microarray that contains probes derived from the sequence of hexaploid wheat, diploid rye and diploid progenitors of hexaploid wheat genome (Lee et al., 2014. Using the array developed, we identified genome-specific transcripts in a wheat–rye translocation line (Lee et al., 2014. Expression data are deposited in the NCBI Gene Expression Omnibus (GEO under accession number GSE58678. Here we report the details of the methods used in the array workflow and data analysis.

Comparative Transcriptional Analyses of Francisella tularensis and Francisella novicida.

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Siva T Sarva

Full Text Available Francisella tularensis is composed of a number of subspecies with varied geographic distribution, host ranges, and virulence. In view of these marked differences, comparative functional genomics may elucidate some of the molecular mechanism(s behind these differences. In this study a shared probe microarray was designed that could be used to compare the transcriptomes of Francisella tularensis subsp. tularensis Schu S4 (Ftt, Francisella tularensis subsp. holarctica OR960246 (Fth, Francisella tularensis subsp. holarctica LVS (LVS, and Francisella novicida U112 (Fn. To gain insight into expression differences that may be related to the differences in virulence of these subspecies, transcriptomes were measured from each strain grown in vitro under identical conditions, utilizing a shared probe microarray. The human avirulent Fn strain exhibited high levels of transcription of genes involved in general metabolism, which are pseudogenes in the human virulent Ftt and Fth strains, consistent with the process of genome decay in the virulent strains. Genes encoding an efflux system (emrA2 cluster of genes, siderophore (fsl operon, acid phosphatase, LPS synthesis, polyamine synthesis, and citrulline ureidase were all highly expressed in Ftt when compared to Fn, suggesting that some of these may contribute to the relative high virulence of Ftt. Genes expressed at a higher level in Ftt when compared to the relatively less virulent Fth included genes encoding isochorismatases, cholylglycine hydrolase, polyamine synthesis, citrulline ureidase, Type IV pilus subunit, and the Francisella Pathogenicity Island protein PdpD. Fth and LVS had very few expression differences, consistent with the derivation of LVS from Fth. This study demonstrated that a shared probe microarray designed to detect transcripts in multiple species/subspecies of Francisella enabled comparative transcriptional analyses that may highlight critical differences that underlie the relative

Genome-wide association of mediator and RNA polymerase II in wild-type and mediator mutant yeast.

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Paul, Emily; Zhu, Z Iris; Landsman, David; Morse, Randall H

2015-01-01

Mediator is a large, multisubunit complex that is required for essentially all mRNA transcription in eukaryotes. In spite of the importance of Mediator, the range of its targets and how it is recruited to these is not well understood. Previous work showed that in Saccharomyces cerevisiae, Mediator contributes to transcriptional activation by two distinct mechanisms, one depending on the tail module triad and favoring SAGA-regulated genes, and the second occurring independently of the tail module and favoring TFIID-regulated genes. Here, we use chromatin immunoprecipitation sequencing (ChIP-seq) to show that dependence on tail module subunits for Mediator recruitment and polymerase II (Pol II) association occurs preferentially at SAGA-regulated over TFIID-regulated genes on a genome-wide scale. We also show that recruitment of tail module subunits to active gene promoters continues genome-wide when Mediator integrity is compromised in med17 temperature-sensitive (ts) yeast, demonstrating the modular nature of the Mediator complex in vivo. In addition, our data indicate that promoters exhibiting strong and stable occupancy by Mediator have a wide range of activity and are enriched for targets of the Tup1-Cyc8 repressor complex. We also identify a number of strong Mediator occupancy peaks that overlap dubious open reading frames (ORFs) and are likely to include previously unrecognized upstream activator sequences. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Transcriptional and phylogenetic analysis of five complete ambystomatid salamander mitochondrial genomes.

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Samuels, Amy K; Weisrock, David W; Smith, Jeramiah J; France, Katherine J; Walker, John A; Putta, Srikrishna; Voss, S Randal

2005-04-11

We report on a study that extended mitochondrial transcript information from a recent EST project to obtain complete mitochondrial genome sequence for 5 tiger salamander complex species (Ambystoma mexicanum, A. t. tigrinum, A. andersoni, A. californiense, and A. dumerilii). We describe, for the first time, aspects of mitochondrial transcription in a representative amphibian, and then use complete mitochondrial sequence data to examine salamander phylogeny at both deep and shallow levels of evolutionary divergence. The available mitochondrial ESTs for A. mexicanum (N=2481) and A. t. tigrinum (N=1205) provided 92% and 87% coverage of the mitochondrial genome, respectively. Complete mitochondrial sequences for all species were rapidly obtained by using long distance PCR and DNA sequencing. A number of genome structural characteristics (base pair length, base composition, gene number, gene boundaries, codon usage) were highly similar among all species and to other distantly related salamanders. Overall, mitochondrial transcription in Ambystoma approximated the pattern observed in other vertebrates. We inferred from the mapping of ESTs onto mtDNA that transcription occurs from both heavy and light strand promoters and continues around the entire length of the mtDNA, followed by post-transcriptional processing. However, the observation of many short transcripts corresponding to rRNA genes indicates that transcription may often terminate prematurely to bias transcription of rRNA genes; indeed an rRNA transcription termination signal sequence was observed immediately following the 16S rRNA gene. Phylogenetic analyses of salamander family relationships consistently grouped Ambystomatidae in a clade containing Cryptobranchidae and Hynobiidae, to the exclusion of Salamandridae. This robust result suggests a novel alternative hypothesis because previous studies have consistently identified Ambystomatidae and Salamandridae as closely related taxa. Phylogenetic analyses of tiger

In vivo genome-wide profiling of RNA secondary structure reveals novel regulatory features.

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Ding, Yiliang; Tang, Yin; Kwok, Chun Kit; Zhang, Yu; Bevilacqua, Philip C; Assmann, Sarah M

2014-01-30

RNA structure has critical roles in processes ranging from ligand sensing to the regulation of translation, polyadenylation and splicing. However, a lack of genome-wide in vivo RNA structural data has limited our understanding of how RNA structure regulates gene expression in living cells. Here we present a high-throughput, genome-wide in vivo RNA structure probing method, structure-seq, in which dimethyl sulphate methylation of unprotected adenines and cytosines is identified by next-generation sequencing. Application of this method to Arabidopsis thaliana seedlings yielded the first in vivo genome-wide RNA structure map at nucleotide resolution for any organism, with quantitative structural information across more than 10,000 transcripts. Our analysis reveals a three-nucleotide periodic repeat pattern in the structure of coding regions, as well as a less-structured region immediately upstream of the start codon, and shows that these features are strongly correlated with translation efficiency. We also find patterns of strong and weak secondary structure at sites of alternative polyadenylation, as well as strong secondary structure at 5' splice sites that correlates with unspliced events. Notably, in vivo structures of messenger RNAs annotated for stress responses are poorly predicted in silico, whereas mRNA structures of genes related to cell function maintenance are well predicted. Global comparison of several structural features between these two categories shows that the mRNAs associated with stress responses tend to have more single-strandedness, longer maximal loop length and higher free energy per nucleotide, features that may allow these RNAs to undergo conformational changes in response to environmental conditions. Structure-seq allows the RNA structurome and its biological roles to be interrogated on a genome-wide scale and should be applicable to any organism.

Genome-Wide Mapping of Collier In Vivo Binding Sites Highlights Its Hierarchical Position in Different Transcription Regulatory Networks.

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Mathilde de Taffin

Full Text Available Collier, the single Drosophila COE (Collier/EBF/Olf-1 transcription factor, is required in several developmental processes, including head patterning and specification of muscle and neuron identity during embryogenesis. To identify direct Collier (Col targets in different cell types, we used ChIP-seq to map Col binding sites throughout the genome, at mid-embryogenesis. In vivo Col binding peaks were associated to 415 potential direct target genes. Gene Ontology analysis revealed a strong enrichment in proteins with DNA binding and/or transcription-regulatory properties. Characterization of a selection of candidates, using transgenic CRM-reporter assays, identified direct Col targets in dorso-lateral somatic muscles and specific neuron types in the central nervous system. These data brought new evidence that Col direct control of the expression of the transcription regulators apterous and eyes-absent (eya is critical to specifying neuronal identities. They also showed that cross-regulation between col and eya in muscle progenitor cells is required for specification of muscle identity, revealing a new parallel between the myogenic regulatory networks operating in Drosophila and vertebrates. Col regulation of eya, both in specific muscle and neuronal lineages, may illustrate one mechanism behind the evolutionary diversification of Col biological roles.

Genome-Wide Mapping of Collier In Vivo Binding Sites Highlights Its Hierarchical Position in Different Transcription Regulatory Networks

Science.gov (United States)

Dubois, Laurence; Bataillé, Laetitia; Painset, Anaïs; Le Gras, Stéphanie; Jost, Bernard; Crozatier, Michèle; Vincent, Alain

2015-01-01

Collier, the single Drosophila COE (Collier/EBF/Olf-1) transcription factor, is required in several developmental processes, including head patterning and specification of muscle and neuron identity during embryogenesis. To identify direct Collier (Col) targets in different cell types, we used ChIP-seq to map Col binding sites throughout the genome, at mid-embryogenesis. In vivo Col binding peaks were associated to 415 potential direct target genes. Gene Ontology analysis revealed a strong enrichment in proteins with DNA binding and/or transcription-regulatory properties. Characterization of a selection of candidates, using transgenic CRM-reporter assays, identified direct Col targets in dorso-lateral somatic muscles and specific neuron types in the central nervous system. These data brought new evidence that Col direct control of the expression of the transcription regulators apterous and eyes-absent (eya) is critical to specifying neuronal identities. They also showed that cross-regulation between col and eya in muscle progenitor cells is required for specification of muscle identity, revealing a new parallel between the myogenic regulatory networks operating in Drosophila and vertebrates. Col regulation of eya, both in specific muscle and neuronal lineages, may illustrate one mechanism behind the evolutionary diversification of Col biological roles. PMID:26204530

Whole-genome transcriptional analysis of heavy metal stresses inCaulobacter crescentus

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Hu, Ping; Brodie, Eoin L.; Suzuki, Yohey; McAdams, Harley H.; Andersen, Gary L.

2005-09-21

The bacterium Caulobacter crescentus and related stalkbacterial species are known for their distinctive ability to live in lownutrient environments, a characteristic of most heavy metal contaminatedsites. Caulobacter crescentus is a model organism for studying cell cycleregulation with well developed genetics. We have identified the pathwaysresponding to heavy metal toxicity in C. crescentus to provide insightsfor possible application of Caulobacter to environmental restoration. Weexposed C. crescentus cells to four heavy metals (chromium, cadmium,selenium and uranium) and analyzed genome wide transcriptional activitiespost exposure using a Affymetrix GeneChip microarray. C. crescentusshowed surprisingly high tolerance to uranium, a possible mechanism forwhich may be formation of extracellular calcium-uranium-phosphateprecipitates. The principal response to these metals was protectionagainst oxidative stress (up-regulation of manganese-dependent superoxidedismutase, sodA). Glutathione S-transferase, thioredoxin, glutaredoxinsand DNA repair enzymes responded most strongly to cadmium and chromate.The cadmium and chromium stress response also focused on reducing theintracellular metal concentration, with multiple efflux pumps employed toremove cadmium while a sulfate transporter was down-regulated to reducenon-specific uptake of chromium. Membrane proteins were also up-regulatedin response to most of the metals tested. A two-component signaltransduction system involved in the uranium response was identified.Several differentially regulated transcripts from regions previously notknown to encode proteins were identified, demonstrating the advantage ofevaluating the transcriptome using whole genome microarrays.

Comparative genomic analysis of pathogenic and probiotic Enterococcus faecalis isolates, and their transcriptional responses to growth in human urine.

Directory of Open Access Journals (Sweden)

Heidi C Vebø

Full Text Available Urinary tract infection (UTI is the most common infection caused by enterococci, and Enterococcus faecalis accounts for the majority of enterococcal infections. Although a number of virulence related traits have been established, no comprehensive genomic or transcriptomic studies have been conducted to investigate how to distinguish pathogenic from non-pathogenic E. faecalis in their ability to cause UTI. In order to identify potential genetic traits or gene regulatory features that distinguish pathogenic from non-pathogenic E. faecalis with respect to UTI, we have performed comparative genomic analysis, and investigated growth capacity and transcriptome profiling in human urine in vitro. Six strains of different origins were cultivated and all grew readily in human urine. The three strains chosen for transcriptional analysis showed an overall similar response with respect to energy and nitrogen metabolism, stress mechanism, cell envelope modifications, and trace metal acquisition. Our results suggest that citrate and aspartate are significant for growth of E. faecalis in human urine, and manganese appear to be a limiting factor. The majority of virulence factors were either not differentially regulated or down-regulated. Notably, a significant up-regulation of genes involved in biofilm formation was observed. Strains from different origins have similar capacity to grow in human urine. The overall similar transcriptional responses between the two pathogenic and the probiotic strain suggest that the pathogenic potential of a certain E. faecalis strain may to a great extent be determined by presence of fitness and virulence factors, rather than the level of expression of such traits.

The transcriptionally active regions in the genome of Bacillus subtilis

DEFF Research Database (Denmark)

Rasmussen, Simon; Nielsen, Henrik Bjørn; Jarmer, Hanne Østergaard

2009-01-01

The majority of all genes have so far been identified and annotated systematically through in silico gene finding. Here we report the finding of 3662 strand-specific transcriptionally active regions (TARs) in the genome of Bacillus subtilis by the use of tiling arrays. We have measured the genome...

Genome-wide methylation analysis identifies genes silenced in non-seminoma cell lines.

Science.gov (United States)

Noor, Dzul Azri Mohamed; Jeyapalan, Jennie N; Alhazmi, Safiah; Carr, Matthew; Squibb, Benjamin; Wallace, Claire; Tan, Christopher; Cusack, Martin; Hughes, Jaime; Reader, Tom; Shipley, Janet; Sheer, Denise; Scotting, Paul J

2016-01-01

Silencing of genes by DNA methylation is a common phenomenon in many types of cancer. However, the genome-wide effect of DNA methylation on gene expression has been analysed in relatively few cancers. Germ cell tumours (GCTs) are a complex group of malignancies. They are unique in developing from a pluripotent progenitor cell. Previous analyses have suggested that non-seminomas exhibit much higher levels of DNA methylation than seminomas. The genomic targets that are methylated, the extent to which this results in gene silencing and the identity of the silenced genes most likely to play a role in the tumours' biology have not yet been established. In this study, genome-wide methylation and expression analysis of GCT cell lines was combined with gene expression data from primary tumours to address this question. Genome methylation was analysed using the Illumina infinium HumanMethylome450 bead chip system and gene expression was analysed using Affymetrix GeneChip Human Genome U133 Plus 2.0 arrays. Regulation by methylation was confirmed by demethylation using 5-aza-2-deoxycytidine and reverse transcription-quantitative PCR. Large differences in the level of methylation of the CpG islands of individual genes between tumour cell lines correlated well with differential gene expression. Treatment of non-seminoma cells with 5-aza-2-deoxycytidine verified that methylation of all genes tested played a role in their silencing in yolk sac tumour cells and many of these genes were also differentially expressed in primary tumours. Genes silenced by methylation in the various GCT cell lines were identified. Several pluripotency-associated genes were identified as a major functional group of silenced genes.

Predicting transcription factor binding sites using local over-representation and comparative genomics

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Touzet Hélène

2006-08-01

Full Text Available Abstract Background Identifying cis-regulatory elements is crucial to understanding gene expression, which highlights the importance of the computational detection of overrepresented transcription factor binding sites (TFBSs in coexpressed or coregulated genes. However, this is a challenging problem, especially when considering higher eukaryotic organisms. Results We have developed a method, named TFM-Explorer, that searches for locally overrepresented TFBSs in a set of coregulated genes, which are modeled by profiles provided by a database of position weight matrices. The novelty of the method is that it takes advantage of spatial conservation in the sequence and supports multiple species. The efficiency of the underlying algorithm and its robustness to noise allow weak regulatory signals to be detected in large heterogeneous data sets. Conclusion TFM-Explorer provides an efficient way to predict TFBS overrepresentation in related sequences. Promising results were obtained in a variety of examples in human, mouse, and rat genomes. The software is publicly available at http://bioinfo.lifl.fr/TFM-Explorer.

Transcription Restores DNA Repair to Heterochromatin, Determining Regional Mutation Rates in Cancer Genomes

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Christina L. Zheng

2014-11-01

Full Text Available Somatic mutations in cancer are more frequent in heterochromatic and late-replicating regions of the genome. We report that regional disparities in mutation density are virtually abolished within transcriptionally silent genomic regions of cutaneous squamous cell carcinomas (cSCCs arising in an XPC−/− background. XPC−/− cells lack global genome nucleotide excision repair (GG-NER, thus establishing differential access of DNA repair machinery within chromatin-rich regions of the genome as the primary cause for the regional disparity. Strikingly, we find that increasing levels of transcription reduce mutation prevalence on both strands of gene bodies embedded within H3K9me3-dense regions, and only to those levels observed in H3K9me3-sparse regions, also in an XPC-dependent manner. Therefore, transcription appears to reduce mutation prevalence specifically by relieving the constraints imposed by chromatin structure on DNA repair. We model this relationship among transcription, chromatin state, and DNA repair, revealing a new, personalized determinant of cancer risk.

Comparative Genome Analysis of Enterobacter cloacae

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Liu, Wing-Yee; Wong, Chi-Fat; Chung, Karl Ming-Kar; Jiang, Jing-Wei; Leung, Frederick Chi-Ching

2013-01-01

The Enterobacter cloacae species includes an extremely diverse group of bacteria that are associated with plants, soil and humans. Publication of the complete genome sequence of the plant growth-promoting endophytic E. cloacae subsp. cloacae ENHKU01 provided an opportunity to perform the first comparative genome analysis between strains of this dynamic species. Examination of the pan-genome of E. cloacae showed that the conserved core genome retains the general physiological and survival genes of the species, while genomic factors in plasmids and variable regions determine the virulence of the human pathogenic E. cloacae strain; additionally, the diversity of fimbriae contributes to variation in colonization and host determination of different E. cloacae strains. Comparative genome analysis further illustrated that E. cloacae strains possess multiple mechanisms for antagonistic action against other microorganisms, which involve the production of siderophores and various antimicrobial compounds, such as bacteriocins, chitinases and antibiotic resistance proteins. The presence of Type VI secretion systems is expected to provide further fitness advantages for E. cloacae in microbial competition, thus allowing it to survive in different environments. Competition assays were performed to support our observations in genomic analysis, where E. cloacae subsp. cloacae ENHKU01 demonstrated antagonistic activities against a wide range of plant pathogenic fungal and bacterial species. PMID:24069314

Genome-wide study of correlations between genomic features and their relationship with the regulation of gene expression.

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Kravatsky, Yuri V; Chechetkin, Vladimir R; Tchurikov, Nikolai A; Kravatskaya, Galina I

2015-02-01

The broad class of tasks in genetics and epigenetics can be reduced to the study of various features that are distributed over the genome (genome tracks). The rapid and efficient processing of the huge amount of data stored in the genome-scale databases cannot be achieved without the software packages based on the analytical criteria. However, strong inhomogeneity of genome tracks hampers the development of relevant statistics. We developed the criteria for the assessment of genome track inhomogeneity and correlations between two genome tracks. We also developed a software package, Genome Track Analyzer, based on this theory. The theory and software were tested on simulated data and were applied to the study of correlations between CpG islands and transcription start sites in the Homo sapiens genome, between profiles of protein-binding sites in chromosomes of Drosophila melanogaster, and between DNA double-strand breaks and histone marks in the H. sapiens genome. Significant correlations between transcription start sites on the forward and the reverse strands were observed in genomes of D. melanogaster, Caenorhabditis elegans, Mus musculus, H. sapiens, and Danio rerio. The observed correlations may be related to the regulation of gene expression in eukaryotes. Genome Track Analyzer is freely available at http://ancorr.eimb.ru/. © The Author 2015. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Genome-wide analysis of replication timing by next-generation sequencing with E/L Repli-seq.

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Marchal, Claire; Sasaki, Takayo; Vera, Daniel; Wilson, Korey; Sima, Jiao; Rivera-Mulia, Juan Carlos; Trevilla-García, Claudia; Nogues, Coralin; Nafie, Ebtesam; Gilbert, David M

2018-05-01

This protocol is an extension to: Nat. Protoc. 6, 870-895 (2014); doi:10.1038/nprot.2011.328; published online 02 June 2011Cycling cells duplicate their DNA content during S phase, following a defined program called replication timing (RT). Early- and late-replicating regions differ in terms of mutation rates, transcriptional activity, chromatin marks and subnuclear position. Moreover, RT is regulated during development and is altered in diseases. Here, we describe E/L Repli-seq, an extension of our Repli-chip protocol. E/L Repli-seq is a rapid, robust and relatively inexpensive protocol for analyzing RT by next-generation sequencing (NGS), allowing genome-wide assessment of how cellular processes are linked to RT. Briefly, cells are pulse-labeled with BrdU, and early and late S-phase fractions are sorted by flow cytometry. Labeled nascent DNA is immunoprecipitated from both fractions and sequenced. Data processing leads to a single bedGraph file containing the ratio of nascent DNA from early versus late S-phase fractions. The results are comparable to those of Repli-chip, with the additional benefits of genome-wide sequence information and an increased dynamic range. We also provide computational pipelines for downstream analyses, for parsing phased genomes using single-nucleotide polymorphisms (SNPs) to analyze RT allelic asynchrony, and for direct comparison to Repli-chip data. This protocol can be performed in up to 3 d before sequencing, and requires basic cellular and molecular biology skills, as well as a basic understanding of Unix and R.

Ebolavirus comparative genomics

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Jun, Se-Ran; Leuze, Michael R.; Nookaew, Intawat; Uberbacher, Edward C.; Land, Miriam; Zhang, Qian; Wanchai, Visanu; Chai, Juanjuan; Nielsen, Morten; Trolle, Thomas; Lund, Ole; Buzard, Gregory S.; Pedersen, Thomas D.; Wassenaar, Trudy M.; Ussery, David W.

2015-01-01

The 2014 Ebola outbreak in West Africa is the largest documented for this virus. To examine the dynamics of this genome, we compare more than 100 currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms a distinct group from all other sequenced viral genomes. All filovirus genomes sequenced to date encode proteins with similar functions and gene order, although there is considerable divergence in sequences between the three genera Ebolavirus, Cuevavirus and Marburgvirus within the family Filoviridae. Whereas all ebolavirus genomes are quite similar (multiple sequences of the same strain are often identical), variation is most common in the intergenic regions and within specific areas of the genes encoding the glycoprotein (GP), nucleoprotein (NP) and polymerase (L). We predict regions that could contain epitope-binding sites, which might be good vaccine targets. This information, combined with glycosylation sites and experimentally determined epitopes, can identify the most promising regions for the development of therapeutic strategies. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). PMID:26175035

New developments of RNAi in Paracoccidioides brasiliensis: prospects for high-throughput, genome-wide, functional genomics.

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Tercio Goes

2014-10-01

Full Text Available The Fungal Genome Initiative of the Broad Institute, in partnership with the Paracoccidioides research community, has recently sequenced the genome of representative isolates of this human-pathogen dimorphic fungus: Pb18 (S1, Pb03 (PS2 and Pb01. The accomplishment of future high-throughput, genome-wide, functional genomics will rely upon appropriate molecular tools and straightforward techniques to streamline the generation of stable loss-of-function phenotypes. In the past decades, RNAi has emerged as the most robust genetic technique to modulate or to suppress gene expression in diverse eukaryotes, including fungi. These molecular tools and techniques, adapted for RNAi, were up until now unavailable for P. brasiliensis.In this paper, we report Agrobacterium tumefaciens mediated transformation of yeast cells for high-throughput applications with which higher transformation frequencies of 150±24 yeast cell transformants per 1×106 viable yeast cells were obtained. Our approach is based on a bifunctional selective marker fusion protein consisted of the Streptoalloteichus hindustanus bleomycin-resistance gene (Shble and the intrinsically fluorescent monomeric protein mCherry which was codon-optimized for heterologous expression in P. brasiliensis. We also report successful GP43 gene knock-down through the expression of intron-containing hairpin RNA (ihpRNA from a Gateway-adapted cassette (cALf which was purpose-built for gene silencing in a high-throughput manner. Gp43 transcript levels were reduced by 73.1±22.9% with this approach.We have a firm conviction that the genetic transformation technique and the molecular tools herein described will have a relevant contribution in future Paracoccidioides spp. functional genomics research.

Genome accessibility is widely preserved and locally modulated during mitosis.

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Hsiung, Chris C-S; Morrissey, Christapher S; Udugama, Maheshi; Frank, Christopher L; Keller, Cheryl A; Baek, Songjoon; Giardine, Belinda; Crawford, Gregory E; Sung, Myong-Hee; Hardison, Ross C; Blobel, Gerd A

2015-02-01

Mitosis entails global alterations to chromosome structure and nuclear architecture, concomitant with transient silencing of transcription. How cells transmit transcriptional states through mitosis remains incompletely understood. While many nuclear factors dissociate from mitotic chromosomes, the observation that certain nuclear factors and chromatin features remain associated with individual loci during mitosis originated the hypothesis that such mitotically retained molecular signatures could provide transcriptional memory through mitosis. To understand the role of chromatin structure in mitotic memory, we performed the first genome-wide comparison of DNase I sensitivity of chromatin in mitosis and interphase, using a murine erythroblast model. Despite chromosome condensation during mitosis visible by microscopy, the landscape of chromatin accessibility at the macromolecular level is largely unaltered. However, mitotic chromatin accessibility is locally dynamic, with individual loci maintaining none, some, or all of their interphase accessibility. Mitotic reduction in accessibility occurs primarily within narrow, highly DNase hypersensitive sites that frequently coincide with transcription factor binding sites, whereas broader domains of moderate accessibility tend to be more stable. In mitosis, proximal promoters generally maintain their accessibility more strongly, whereas distal regulatory elements tend to lose accessibility. Large domains of DNA hypomethylation mark a subset of promoters that retain accessibility during mitosis and across many cell types in interphase. Erythroid transcription factor GATA1 exerts site-specific changes in interphase accessibility that are most pronounced at distal regulatory elements, but has little influence on mitotic accessibility. We conclude that features of open chromatin are remarkably stable through mitosis, but are modulated at the level of individual genes and regulatory elements. © 2015 Hsiung et al.; Published by

A Web-Based Comparative Genomics Tutorial for Investigating Microbial Genomes

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Michael Strong

2009-12-01

Full Text Available As the number of completely sequenced microbial genomes continues to rise at an impressive rate, it is important to prepare students with the skills necessary to investigate microorganisms at the genomic level. As a part of the core curriculum for first-year graduate students in the biological sciences, we have implemented a web-based tutorial to introduce students to the fields of comparative and functional genomics. The tutorial focuses on recent computational methods for identifying functionally linked genes and proteins on a genome-wide scale and was used to introduce students to the Rosetta Stone, Phylogenetic Profile, conserved Gene Neighbor, and Operon computational methods. Students learned to use a number of publicly available web servers and databases to identify functionally linked genes in the Escherichia coli genome, with emphasis on genome organization and operon structure. The overall effectiveness of the tutorial was assessed based on student evaluations and homework assignments. The tutorial is available to other educators at http://www.doe-mbi.ucla.edu/~strong/m253.php.

A genome-wide characterization of microRNA genes in maize.

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Lifang Zhang

2009-11-01

Full Text Available MicroRNAs (miRNAs are small, non-coding RNAs that play essential roles in plant growth, development, and stress response. We conducted a genome-wide survey of maize miRNA genes, characterizing their structure, expression, and evolution. Computational approaches based on homology and secondary structure modeling identified 150 high-confidence genes within 26 miRNA families. For 25 families, expression was verified by deep-sequencing of small RNA libraries that were prepared from an assortment of maize tissues. PCR-RACE amplification of 68 miRNA transcript precursors, representing 18 families conserved across several plant species, showed that splice variation and the use of alternative transcriptional start and stop sites is common within this class of genes. Comparison of sequence variation data from diverse maize inbred lines versus teosinte accessions suggest that the mature miRNAs are under strong purifying selection while the flanking sequences evolve equivalently to other genes. Since maize is derived from an ancient tetraploid, the effect of whole-genome duplication on miRNA evolution was examined. We found that, like protein-coding genes, duplicated miRNA genes underwent extensive gene-loss, with approximately 35% of ancestral sites retained as duplicate homoeologous miRNA genes. This number is higher than that observed with protein-coding genes. A search for putative miRNA targets indicated bias towards genes in regulatory and metabolic pathways. As maize is one of the principal models for plant growth and development, this study will serve as a foundation for future research into the functional roles of miRNA genes.

Long-term in vitro, cell-type-specific genome-wide reprogramming of gene expression

International Nuclear Information System (INIS)

Hakelien, Anne-Mari; Gaustad, Kristine G.; Taranger, Christel K.; Skalhegg, Bjorn S.; Kuentziger, Thomas; Collas, Philippe

2005-01-01

We demonstrate a cell extract-based, genome-wide and heritable reprogramming of gene expression in vitro. Kidney epithelial 293T cells have previously been shown to take on T cell properties following a brief treatment with an extract of Jurkat T cells. We show here that 293T cells exposed for 1 h to a Jurkat cell extract undergo genome-wide, target cell-type-specific and long-lasting transcriptional changes. Microarray analyses indicate that on any given week after extract treatment, ∼2500 genes are upregulated >3-fold, of which ∼900 are also expressed in Jurkat cells. Concomitantly, ∼1500 genes are downregulated or repressed, of which ∼500 are also downregulated in Jurkat cells. Gene expression changes persist for over 30 passages (∼80 population doublings) in culture. Target cell-type specificity of these changes is shown by the lack of activation or repression of Jurkat-specific genes by extracts of 293T cells or carcinoma cells. Quantitative RT-PCR analysis confirms the long-term transcriptional activation of genes involved in key T cell functions. Additionally, growth of cells in suspended aggregates, expression of CD3 and CD28 T cell surface markers, and interleukin-2 secretion by 293T cells treated with extract of adult peripheral blood T cells illustrate a functional nuclear reprogramming. Therefore, target cell-type-specific and heritable changes in gene expression, and alterations in cell function, can be promoted by extracts derived from transformed cells as well as from adult primary cells

Genome-wide association study of multiplex schizophrenia pedigrees

DEFF Research Database (Denmark)

Levinson, Douglas F; Shi, Jianxin; Wang, Kai

2012-01-01

The authors used a genome-wide association study (GWAS) of multiply affected families to investigate the association of schizophrenia to common single-nucleotide polymorphisms (SNPs) and rare copy number variants (CNVs).......The authors used a genome-wide association study (GWAS) of multiply affected families to investigate the association of schizophrenia to common single-nucleotide polymorphisms (SNPs) and rare copy number variants (CNVs)....

CRISPR-Cas9-Mediated Genome Editing and Transcriptional Control in Yarrowia lipolytica.

Science.gov (United States)

Schwartz, Cory; Wheeldon, Ian

2018-01-01

The discovery and adaptation of RNA-guided nucleases has resulted in the rapid development of efficient, scalable, and easily accessible synthetic biology tools for targeted genome editing and transcriptional control. In these systems, for example CRISPR-Cas9 from Streptococcus pyogenes, a protein with nuclease activity is targeted to a specific nucleotide sequence by a short RNA molecule, whereupon binding it cleaves the targeted nucleotide strand. To extend this genome-editing ability to the industrially important oleaginous yeast Yarrowia lipolytica, we developed a set of easily usable and effective CRISPR-Cas9 episomal vectors. In this protocols chapter, we first present a method by which arbitrary protein-coding genes can be disrupted via indel formation after CRISPR-Cas9 targeting. A second method demonstrates how the same CRISPR-Cas9 system can be used to induce markerless gene cassette integration into the genome by inducing homologous recombination after DNA cleavage by Cas9. Finally, we describe how a catalytically inactive form of Cas9 fused to a transcriptional repressor can be used to control transcription of native genes in Y. lipolytica. The CRISPR-Cas9 tools and strategies described here greatly increase the types of genome editing and transcriptional control that can be achieved in Y. lipolytica, and promise to facilitate more advanced engineering of this important oleaginous host.

The Intertwined Roles of DNA Damage and Transcription

OpenAIRE

Di Palo, Giacomo

2016-01-01

DNA damage and transcription are two interconnected events. Transcription can induce damage and scheduled DNA damage can be required for transcription. Here, we analyzed genome-wide distribution of 8oxodG-marked oxidative DNA damage obtained by OxiDIP-Seq, and we found a correlation with transcription of protein coding genes.

Genome-wide identification of significant aberrations in cancer genome.

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Yuan, Xiguo; Yu, Guoqiang; Hou, Xuchu; Shih, Ie-Ming; Clarke, Robert; Zhang, Junying; Hoffman, Eric P; Wang, Roger R; Zhang, Zhen; Wang, Yue

2012-07-27

Somatic Copy Number Alterations (CNAs) in human genomes are present in almost all human cancers. Systematic efforts to characterize such structural variants must effectively distinguish significant consensus events from random background aberrations. Here we introduce Significant Aberration in Cancer (SAIC), a new method for characterizing and assessing the statistical significance of recurrent CNA units. Three main features of SAIC include: (1) exploiting the intrinsic correlation among consecutive probes to assign a score to each CNA unit instead of single probes; (2) performing permutations on CNA units that preserve correlations inherent in the copy number data; and (3) iteratively detecting Significant Copy Number Aberrations (SCAs) and estimating an unbiased null distribution by applying an SCA-exclusive permutation scheme. We test and compare the performance of SAIC against four peer methods (GISTIC, STAC, KC-SMART, CMDS) on a large number of simulation datasets. Experimental results show that SAIC outperforms peer methods in terms of larger area under the Receiver Operating Characteristics curve and increased detection power. We then apply SAIC to analyze structural genomic aberrations acquired in four real cancer genome-wide copy number data sets (ovarian cancer, metastatic prostate cancer, lung adenocarcinoma, glioblastoma). When compared with previously reported results, SAIC successfully identifies most SCAs known to be of biological significance and associated with oncogenes (e.g., KRAS, CCNE1, and MYC) or tumor suppressor genes (e.g., CDKN2A/B). Furthermore, SAIC identifies a number of novel SCAs in these copy number data that encompass tumor related genes and may warrant further studies. Supported by a well-grounded theoretical framework, SAIC has been developed and used to identify SCAs in various cancer copy number data sets, providing useful information to study the landscape of cancer genomes. Open-source and platform-independent SAIC software is

Genome-wide nucleosome map and cytosine methylation levels of an ancient human genome

DEFF Research Database (Denmark)

Pedersen, Jakob Skou; Valen, Eivind; Velazquez, Amhed Missael Vargas

2014-01-01

Epigenetic information is available from contemporary organisms, but is difficult to track back in evolutionary time. Here, we show that genome-wide epigenetic information can be gathered directly from next-generation sequence reads of DNA isolated from ancient remains. Using the genome sequence...... data generated from hair shafts of a 4000-yr-old Paleo-Eskimo belonging to the Saqqaq culture, we generate the first ancient nucleosome map coupled with a genome-wide survey of cytosine methylation levels. The validity of both nucleosome map and methylation levels were confirmed by the recovery...

Genome-wide DNA methylation maps in follicular lymphoma cells determined by methylation-enriched bisulfite sequencing.

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Jeong-Hyeon Choi

Full Text Available BACKGROUND: Follicular lymphoma (FL is a form of non-Hodgkin's lymphoma (NHL that arises from germinal center (GC B-cells. Despite the significant advances in immunotherapy, FL is still not curable. Beyond transcriptional profiling and genomics datasets, there currently is no epigenome-scale dataset or integrative biology approach that can adequately model this disease and therefore identify novel mechanisms and targets for successful prevention and treatment of FL. METHODOLOGY/PRINCIPAL FINDINGS: We performed methylation-enriched genome-wide bisulfite sequencing of FL cells and normal CD19(+ B-cells using 454 sequencing technology. The methylated DNA fragments were enriched with methyl-binding proteins, treated with bisulfite, and sequenced using the Roche-454 GS FLX sequencer. The total number of bases covered in the human genome was 18.2 and 49.3 million including 726,003 and 1.3 million CpGs in FL and CD19(+ B-cells, respectively. 11,971 and 7,882 methylated regions of interest (MRIs were identified respectively. The genome-wide distribution of these MRIs displayed significant differences between FL and normal B-cells. A reverse trend in the distribution of MRIs between the promoter and the gene body was observed in FL and CD19(+ B-cells. The MRIs identified in FL cells also correlated well with transcriptomic data and ChIP-on-Chip analyses of genome-wide histone modifications such as tri-methyl-H3K27, and tri-methyl-H3K4, indicating a concerted epigenetic alteration in FL cells. CONCLUSIONS/SIGNIFICANCE: This study is the first to provide a large scale and comprehensive analysis of the DNA methylation sequence composition and distribution in the FL epigenome. These integrated approaches have led to the discovery of novel and frequent targets of aberrant epigenetic alterations. The genome-wide bisulfite sequencing approach developed here can be a useful tool for profiling DNA methylation in clinical samples.

Conflict Resolution in the Genome: How Transcription and Replication Make It Work.

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Hamperl, Stephan; Cimprich, Karlene A

2016-12-01

The complex machineries involved in replication and transcription translocate along the same DNA template, often in opposing directions and at different rates. These processes routinely interfere with each other in prokaryotes, and mounting evidence now suggests that RNA polymerase complexes also encounter replication forks in higher eukaryotes. Indeed, cells rely on numerous mechanisms to avoid, tolerate, and resolve such transcription-replication conflicts, and the absence of these mechanisms can lead to catastrophic effects on genome stability and cell viability. In this article, we review the cellular responses to transcription-replication conflicts and highlight how these inevitable encounters shape the genome and impact diverse cellular processes. Copyright © 2016 Elsevier Inc. All rights reserved.

New families of human regulatory RNA structures identified by comparative analysis of vertebrate genomes

DEFF Research Database (Denmark)

Parker, Brian John; Moltke, Ida; Roth, Adam

2011-01-01

a comparative method, EvoFam, for genome-wide identification of families of regulatory RNA structures, based on primary sequence and secondary structure similarity. We apply EvoFam to a 41-way genomic vertebrate alignment. Genome-wide, we identify 220 human, high-confidence families outside protein...

Comprehensive evaluation of genome-wide 5-hydroxymethylcytosine profiling approaches in human DNA.

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Skvortsova, Ksenia; Zotenko, Elena; Luu, Phuc-Loi; Gould, Cathryn M; Nair, Shalima S; Clark, Susan J; Stirzaker, Clare

2017-01-01

The discovery that 5-methylcytosine (5mC) can be oxidized to 5-hydroxymethylcytosine (5hmC) by the ten-eleven translocation (TET) proteins has prompted wide interest in the potential role of 5hmC in reshaping the mammalian DNA methylation landscape. The gold-standard bisulphite conversion technologies to study DNA methylation do not distinguish between 5mC and 5hmC. However, new approaches to mapping 5hmC genome-wide have advanced rapidly, although it is unclear how the different methods compare in accurately calling 5hmC. In this study, we provide a comparative analysis on brain DNA using three 5hmC genome-wide approaches, namely whole-genome bisulphite/oxidative bisulphite sequencing (WG Bis/OxBis-seq), Infinium HumanMethylation450 BeadChip arrays coupled with oxidative bisulphite (HM450K Bis/OxBis) and antibody-based immunoprecipitation and sequencing of hydroxymethylated DNA (hMeDIP-seq). We also perform loci-specific TET-assisted bisulphite sequencing (TAB-seq) for validation of candidate regions. We show that whole-genome single-base resolution approaches are advantaged in providing precise 5hmC values but require high sequencing depth to accurately measure 5hmC, as this modification is commonly in low abundance in mammalian cells. HM450K arrays coupled with oxidative bisulphite provide a cost-effective representation of 5hmC distribution, at CpG sites with 5hmC levels >~10%. However, 5hmC analysis is restricted to the genomic location of the probes, which is an important consideration as 5hmC modification is commonly enriched at enhancer elements. Finally, we show that the widely used hMeDIP-seq method provides an efficient genome-wide profile of 5hmC and shows high correlation with WG Bis/OxBis-seq 5hmC distribution in brain DNA. However, in cell line DNA with low levels of 5hmC, hMeDIP-seq-enriched regions are not detected by WG Bis/OxBis or HM450K, either suggesting misinterpretation of 5hmC calls by hMeDIP or lack of sensitivity of the latter methods. We

Adiponectin Concentrations: A Genome-wide Association Study

OpenAIRE

Jee, Sun Ha; Sull, Jae Woong; Lee, Jong-Eun; Shin, Chol; Park, Jongkeun; Kimm, Heejin; Cho, Eun-Young; Shin, Eun-Soon; Yun, Ji Eun; Park, Ji Wan; Kim, Sang Yeun; Lee, Sun Ju; Jee, Eun Jung; Baik, Inkyung; Kao, Linda

2010-01-01

Adiponectin is associated with obesity and insulin resistance. To date, there has been no genome-wide association study (GWAS) of adiponectin levels in Asians. Here we present a GWAS of a cohort of Korean volunteers. A total of 4,001 subjects were genotyped by using a genome-wide marker panel in a two-stage design (979 subjects initially and 3,022 in a second stage). Another 2,304 subjects were used for follow-up replication studies with selected markers. In the discovery phase, the top SNP a...

Genome-wide indel markers shared by diverse Asian rice cultivars compared to Japanese rice cultivar ?Koshihikari?

OpenAIRE

Yonemaru, Jun-ichi; Choi, Sun Hee; Sakai, Hiroaki; Ando, Tsuyu; Shomura, Ayahiko; Yano, Masahiro; Wu, Jianzhong; Fukuoka, Shuichi

2015-01-01

Insertion-deletion (indel) polymorphisms, such as simple sequence repeats, have been widely used as DNA markers to identify QTLs and genes and to facilitate rice breeding. Recently, next-generation sequencing has produced deep sequences that allow genome-wide detection of indels. These polymorphisms can potentially be used to develop high-accuracy polymerase chain reaction (PCR)-based markers. Here, re-sequencing of 5 indica, 2 aus, and 3 tropical japonica cultivars and Japanese elite cultiva...

Genomic dissection of conserved transcriptional regulation in intestinal epithelial cells.

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Colin R Lickwar

2017-08-01

Full Text Available The intestinal epithelium serves critical physiologic functions that are shared among all vertebrates. However, it is unknown how the transcriptional regulatory mechanisms underlying these functions have changed over the course of vertebrate evolution. We generated genome-wide mRNA and accessible chromatin data from adult intestinal epithelial cells (IECs in zebrafish, stickleback, mouse, and human species to determine if conserved IEC functions are achieved through common transcriptional regulation. We found evidence for substantial common regulation and conservation of gene expression regionally along the length of the intestine from fish to mammals and identified a core set of genes comprising a vertebrate IEC signature. We also identified transcriptional start sites and other putative regulatory regions that are differentially accessible in IECs in all 4 species. Although these sites rarely showed sequence conservation from fish to mammals, surprisingly, they drove highly conserved IEC expression in a zebrafish reporter assay. Common putative transcription factor binding sites (TFBS found at these sites in multiple species indicate that sequence conservation alone is insufficient to identify much of the functionally conserved IEC regulatory information. Among the rare, highly sequence-conserved, IEC-specific regulatory regions, we discovered an ancient enhancer upstream from her6/HES1 that is active in a distinct population of Notch-positive cells in the intestinal epithelium. Together, these results show how combining accessible chromatin and mRNA datasets with TFBS prediction and in vivo reporter assays can reveal tissue-specific regulatory information conserved across 420 million years of vertebrate evolution. We define an IEC transcriptional regulatory network that is shared between fish and mammals and establish an experimental platform for studying how evolutionarily distilled regulatory information commonly controls IEC development

TIGER: Toolbox for integrating genome-scale metabolic models, expression data, and transcriptional regulatory networks

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Jensen Paul A

2011-09-01

Full Text Available Abstract Background Several methods have been developed for analyzing genome-scale models of metabolism and transcriptional regulation. Many of these methods, such as Flux Balance Analysis, use constrained optimization to predict relationships between metabolic flux and the genes that encode and regulate enzyme activity. Recently, mixed integer programming has been used to encode these gene-protein-reaction (GPR relationships into a single optimization problem, but these techniques are often of limited generality and lack a tool for automating the conversion of rules to a coupled regulatory/metabolic model. Results We present TIGER, a Toolbox for Integrating Genome-scale Metabolism, Expression, and Regulation. TIGER converts a series of generalized, Boolean or multilevel rules into a set of mixed integer inequalities. The package also includes implementations of existing algorithms to integrate high-throughput expression data with genome-scale models of metabolism and transcriptional regulation. We demonstrate how TIGER automates the coupling of a genome-scale metabolic model with GPR logic and models of transcriptional regulation, thereby serving as a platform for algorithm development and large-scale metabolic analysis. Additionally, we demonstrate how TIGER's algorithms can be used to identify inconsistencies and improve existing models of transcriptional regulation with examples from the reconstructed transcriptional regulatory network of Saccharomyces cerevisiae. Conclusion The TIGER package provides a consistent platform for algorithm development and extending existing genome-scale metabolic models with regulatory networks and high-throughput data.

Genome-Wide Association Studies Suggest Limited Immune Gene Enrichment in Schizophrenia Compared to 5 Autoimmune Diseases

DEFF Research Database (Denmark)

Pouget, Jennie G; Gonçalves, Vanessa F; Spain, Sarah L

2016-01-01

There has been intense debate over the immunological basis of schizophrenia, and the potential utility of adjunct immunotherapies. The major histocompatibility complex is consistently the most powerful region of association in genome-wide association studies (GWASs) of schizophrenia and has been...... in immune genes contributes to schizophrenia. We show that there is no enrichment of immune loci outside of the MHC region in the largest genetic study of schizophrenia conducted to date, in contrast to 5 diseases of known immune origin. Among 108 regions of the genome previously associated...

Genome wide binding (ChIP-Seq of murine Bapx1 and Sox9 proteins in vivo and in vitro

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Sumantra Chatterjee

2016-12-01

Full Text Available This work pertains to GEO submission GSE36672, in vivo and in vitro genome wide binding (ChIP-Seq of Bapx1/Nkx3.2 and Sox9 proteins. We have previously shown that data from a genome wide binding assay combined with transcriptional profiling is an insightful means to divulge the mechanisms directing cell type specification and the generation of tissues and subsequent organs [1]. Our earlier work identified the role of the DNA-binding homeodomain containing protein Bapx1/Nkx3.2 in midgestation murine embryos. Microarray analysis of EGFP-tagged cells (both wildtype and null was integrated using ChIP-Seq analysis of Bapx1/Nkx3.2 and Sox9 DNA-binding proteins in living tissue.

Discovering transcription factor binding sites in highly repetitive regions of genomes with multi-read analysis of ChIP-Seq data.

Science.gov (United States)

Chung, Dongjun; Kuan, Pei Fen; Li, Bo; Sanalkumar, Rajendran; Liang, Kun; Bresnick, Emery H; Dewey, Colin; Keleş, Sündüz

2011-07-01

Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) is rapidly replacing chromatin immunoprecipitation combined with genome-wide tiling array analysis (ChIP-chip) as the preferred approach for mapping transcription-factor binding sites and chromatin modifications. The state of the art for analyzing ChIP-seq data relies on using only reads that map uniquely to a relevant reference genome (uni-reads). This can lead to the omission of up to 30% of alignable reads. We describe a general approach for utilizing reads that map to multiple locations on the reference genome (multi-reads). Our approach is based on allocating multi-reads as fractional counts using a weighted alignment scheme. Using human STAT1 and mouse GATA1 ChIP-seq datasets, we illustrate that incorporation of multi-reads significantly increases sequencing depths, leads to detection of novel peaks that are not otherwise identifiable with uni-reads, and improves detection of peaks in mappable regions. We investigate various genome-wide characteristics of peaks detected only by utilization of multi-reads via computational experiments. Overall, peaks from multi-read analysis have similar characteristics to peaks that are identified by uni-reads except that the majority of them reside in segmental duplications. We further validate a number of GATA1 multi-read only peaks by independent quantitative real-time ChIP analysis and identify novel target genes of GATA1. These computational and experimental results establish that multi-reads can be of critical importance for studying transcription factor binding in highly repetitive regions of genomes with ChIP-seq experiments.

Discovering transcription factor binding sites in highly repetitive regions of genomes with multi-read analysis of ChIP-Seq data.

Directory of Open Access Journals (Sweden)

Dongjun Chung

2011-07-01

Full Text Available Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq is rapidly replacing chromatin immunoprecipitation combined with genome-wide tiling array analysis (ChIP-chip as the preferred approach for mapping transcription-factor binding sites and chromatin modifications. The state of the art for analyzing ChIP-seq data relies on using only reads that map uniquely to a relevant reference genome (uni-reads. This can lead to the omission of up to 30% of alignable reads. We describe a general approach for utilizing reads that map to multiple locations on the reference genome (multi-reads. Our approach is based on allocating multi-reads as fractional counts using a weighted alignment scheme. Using human STAT1 and mouse GATA1 ChIP-seq datasets, we illustrate that incorporation of multi-reads significantly increases sequencing depths, leads to detection of novel peaks that are not otherwise identifiable with uni-reads, and improves detection of peaks in mappable regions. We investigate various genome-wide characteristics of peaks detected only by utilization of multi-reads via computational experiments. Overall, peaks from multi-read analysis have similar characteristics to peaks that are identified by uni-reads except that the majority of them reside in segmental duplications. We further validate a number of GATA1 multi-read only peaks by independent quantitative real-time ChIP analysis and identify novel target genes of GATA1. These computational and experimental results establish that multi-reads can be of critical importance for studying transcription factor binding in highly repetitive regions of genomes with ChIP-seq experiments.

Nencki Genomics Database--Ensembl funcgen enhanced with intersections, user data and genome-wide TFBS motifs.

Science.gov (United States)

Krystkowiak, Izabella; Lenart, Jakub; Debski, Konrad; Kuterba, Piotr; Petas, Michal; Kaminska, Bozena; Dabrowski, Michal

2013-01-01

We present the Nencki Genomics Database, which extends the functionality of Ensembl Regulatory Build (funcgen) for the three species: human, mouse and rat. The key enhancements over Ensembl funcgen include the following: (i) a user can add private data, analyze them alongside the public data and manage access rights; (ii) inside the database, we provide efficient procedures for computing intersections between regulatory features and for mapping them to the genes. To Ensembl funcgen-derived data, which include data from ENCODE, we add information on conserved non-coding (putative regulatory) sequences, and on genome-wide occurrence of transcription factor binding site motifs from the current versions of two major motif libraries, namely, Jaspar and Transfac. The intersections and mapping to the genes are pre-computed for the public data, and the result of any procedure run on the data added by the users is stored back into the database, thus incrementally increasing the body of pre-computed data. As the Ensembl funcgen schema for the rat is currently not populated, our database is the first database of regulatory features for this frequently used laboratory animal. The database is accessible without registration using the mysql client: mysql -h database.nencki-genomics.org -u public. Registration is required only to add or access private data. A WSDL webservice provides access to the database from any SOAP client, including the Taverna Workbench with a graphical user interface.

Genome-Wide Mapping of Transcriptional Regulation and Metabolism Describes Information-Processing Units in Escherichia coli

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Daniela Ledezma-Tejeida

2017-08-01

Full Text Available In the face of changes in their environment, bacteria adjust gene expression levels and produce appropriate responses. The individual layers of this process have been widely studied: the transcriptional regulatory network describes the regulatory interactions that produce changes in the metabolic network, both of which are coordinated by the signaling network, but the interplay between them has never been described in a systematic fashion. Here, we formalize the process of detection and processing of environmental information mediated by individual transcription factors (TFs, utilizing a concept termed genetic sensory response units (GENSOR units, which are composed of four components: (1 a signal, (2 signal transduction, (3 genetic switch, and (4 a response. We used experimentally validated data sets from two databases to assemble a GENSOR unit for each of the 189 local TFs of Escherichia coli K-12 contained in the RegulonDB database. Further analysis suggested that feedback is a common occurrence in signal processing, and there is a gradient of functional complexity in the response mediated by each TF, as opposed to a one regulator/one pathway rule. Finally, we provide examples of other GENSOR unit applications, such as hypothesis generation, detailed description of cellular decision making, and elucidation of indirect regulatory mechanisms.

Human Metapneumovirus Induces Formation of Inclusion Bodies for Efficient Genome Replication and Transcription.

Science.gov (United States)

Cifuentes-Muñoz, Nicolás; Branttie, Jean; Slaughter, Kerri Beth; Dutch, Rebecca Ellis

2017-12-15

Human metapneumovirus (HMPV) causes significant upper and lower respiratory disease in all age groups worldwide. The virus possesses a negative-sense single-stranded RNA genome of approximately 13.3 kb encapsidated by multiple copies of the nucleoprotein (N), giving rise to helical nucleocapsids. In addition, copies of the phosphoprotein (P) and the large RNA polymerase (L) decorate the viral nucleocapsids. After viral attachment, endocytosis, and fusion mediated by the viral glycoproteins, HMPV nucleocapsids are released into the cell cytoplasm. To visualize the subsequent steps of genome transcription and replication, a fluorescence in situ hybridization (FISH) protocol was established to detect different viral RNA subpopulations in infected cells. The FISH probes were specific for detection of HMPV positive-sense RNA (+RNA) and viral genomic RNA (vRNA). Time course analysis of human bronchial epithelial BEAS-2B cells infected with HMPV revealed the formation of inclusion bodies (IBs) from early times postinfection. HMPV IBs were shown to be cytoplasmic sites of active transcription and replication, with the translation of viral proteins being closely associated. Inclusion body formation was consistent with an actin-dependent coalescence of multiple early replicative sites. Time course quantitative reverse transcription-PCR analysis suggested that the coalescence of inclusion bodies is a strategy to efficiently replicate and transcribe the viral genome. These results provide a better understanding of the steps following HMPV entry and have important clinical implications. IMPORTANCE Human metapneumovirus (HMPV) is a recently discovered pathogen that affects human populations of all ages worldwide. Reinfections are common throughout life, but no vaccines or antiviral treatments are currently available. In this work, a spatiotemporal analysis of HMPV replication and transcription in bronchial epithelial cell-derived immortal cells was performed. HMPV was shown to

Genome-wide expressions in autologous eutopic and ectopic endometrium of fertile women with endometriosis.

Science.gov (United States)

Khan, Meraj A; Sengupta, Jayasree; Mittal, Suneeta; Ghosh, Debabrata

2012-09-24

In order to obtain a lead of the pathophysiology of endometriosis, genome-wide expressional analyses of eutopic and ectopic endometrium have earlier been reported, however, the effects of stages of severity and phases of menstrual cycle on expressional profiles have not been examined. The effect of genetic heterogeneity and fertility history on transcriptional activity was also not considered. In the present study, a genome-wide expression analysis of autologous, paired eutopic and ectopic endometrial samples obtained from fertile women (n=18) suffering from moderate (stage 3; n=8) or severe (stage 4; n=10) ovarian endometriosis during proliferative (n=13) and secretory (n=5) phases of menstrual cycle was performed. Individual pure RNA samples were subjected to Agilent's Whole Human Genome 44K microarray experiments. Microarray data were validated (Pcopy numbers by performing real time RT-PCR of seven (7) arbitrarily selected genes in all samples. The data obtained were subjected to differential expression (DE) and differential co-expression (DC) analyses followed by networks and enrichment analysis, and gene set enrichment analysis (GSEA). The reproducibility of prediction based on GSEA implementation of DC results was assessed by examining the relative expressions of twenty eight (28) selected genes in RNA samples obtained from fresh pool of eutopic and ectopic samples from confirmed ovarian endometriosis patients with stages 3 and 4 (n=4/each) during proliferative and secretory (n=4/each) phases. Higher clustering effect of pairing (cluster distance, cd=0.1) in samples from same individuals on expressional arrays among eutopic and ectopic samples was observed as compared to that of clinical stages of severity (cd=0.5) and phases of menstrual cycle (cd=0.6). Post hoc analysis revealed anomaly in the expressional profiles of several genes associated with immunological, neuracrine and endocrine functions and gynecological cancers however with no overt oncogenic

Genome-wide mapping of DNA strand breaks.

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Frédéric Leduc

Full Text Available Determination of cellular DNA damage has so far been limited to global assessment of genome integrity whereas nucleotide-level mapping has been restricted to specific loci by the use of specific primers. Therefore, only limited DNA sequences can be studied and novel regions of genomic instability can hardly be discovered. Using a well-characterized yeast model, we describe a straightforward strategy to map genome-wide DNA strand breaks without compromising nucleotide-level resolution. This technique, termed "damaged DNA immunoprecipitation" (dDIP, uses immunoprecipitation and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin end-labeling (TUNEL to capture DNA at break sites. When used in combination with microarray or next-generation sequencing technologies, dDIP will allow researchers to map genome-wide DNA strand breaks as well as other types of DNA damage and to establish a clear profiling of altered genes and/or intergenic sequences in various experimental conditions. This mapping technique could find several applications for instance in the study of aging, genotoxic drug screening, cancer, meiosis, radiation and oxidative DNA damage.

ChIP on SNP-chip for genome-wide analysis of human histone H4 hyperacetylation

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Porter Christopher J

2007-09-01

Full Text Available Abstract Background SNP microarrays are designed to genotype Single Nucleotide Polymorphisms (SNPs. These microarrays report hybridization of DNA fragments and therefore can be used for the purpose of detecting genomic fragments. Results Here, we demonstrate that a SNP microarray can be effectively used in this way to perform chromatin immunoprecipitation (ChIP on chip as an alternative to tiling microarrays. We illustrate this novel application by mapping whole genome histone H4 hyperacetylation in human myoblasts and myotubes. We detect clusters of hyperacetylated histone H4, often spanning across up to 300 kilobases of genomic sequence. Using complementary genome-wide analyses of gene expression by DNA microarray we demonstrate that these clusters of hyperacetylated histone H4 tend to be associated with expressed genes. Conclusion The use of a SNP array for a ChIP-on-chip application (ChIP on SNP-chip will be of great value to laboratories whose interest is the determination of general rules regarding the relationship of specific chromatin modifications to transcriptional status throughout the genome and to examine the asymmetric modification of chromatin at heterozygous loci.

Identification of a novel FGFRL1 MicroRNA target site polymorphism for bone mineral density in meta-analyses of genome-wide association studies

NARCIS (Netherlands)

T. Niu (Tianhua); N. Liu (Ning); M. Zhao (Ming); G. Xie (Guie); L. Zhang (Lei); J. Li (Jian); Y.-F. Pei (Yu-Fang); H. Shen (Hui); X. Fu (Xiaoying); H. He (Hao); S. Lu (Shan); X. Chen (Xiangding); L. Tan (Lijun); T.-L. Yang (Tie-Lin); Y. Guo (Yan); P.J. Leo (Paul); E.L. Duncan (Emma); J. Shen (Jie); Y.-F. Guo (Yan-fang); G.C. Nicholson (Geoffrey); R.L. Prince (Richard L.); J.A. Eisman (John); G. Jones (Graeme); P.N. Sambrook (Philip); X. Hu (Xiang); P.M. Das (Partha M.); Q. Tian (Qing); X.-Z. Zhu (Xue-Zhen); C.J. Papasian (Christopher J.); M.A. Brown (Matthew); A.G. Uitterlinden (André); Y.-P. Wang (Yu-Ping); S. Xiang (Shuanglin); H.-W. Deng

2015-01-01

textabstractMicroRNAs (miRNAs) are critical post-transcriptional regulators. Based on a previous genome-wide association (GWA) scan, we conducted a polymorphism in microRNAs' Target Sites (poly-miRTS)-centric multistage meta-analysis for lumbar spine (LS)-, total hip (HIP)-, and femoral neck

MicroScope: a platform for microbial genome annotation and comparative genomics.

Science.gov (United States)

Vallenet, D; Engelen, S; Mornico, D; Cruveiller, S; Fleury, L; Lajus, A; Rouy, Z; Roche, D; Salvignol, G; Scarpelli, C; Médigue, C

2009-01-01

The initial outcome of genome sequencing is the creation of long text strings written in a four letter alphabet. The role of in silico sequence analysis is to assist biologists in the act of associating biological knowledge with these sequences, allowing investigators to make inferences and predictions that can be tested experimentally. A wide variety of software is available to the scientific community, and can be used to identify genomic objects, before predicting their biological functions. However, only a limited number of biologically interesting features can be revealed from an isolated sequence. Comparative genomics tools, on the other hand, by bringing together the information contained in numerous genomes simultaneously, allow annotators to make inferences based on the idea that evolution and natural selection are central to the definition of all biological processes. We have developed the MicroScope platform in order to offer a web-based framework for the systematic and efficient revision of microbial genome annotation and comparative analysis (http://www.genoscope.cns.fr/agc/microscope). Starting with the description of the flow chart of the annotation processes implemented in the MicroScope pipeline, and the development of traditional and novel microbial annotation and comparative analysis tools, this article emphasizes the essential role of expert annotation as a complement of automatic annotation. Several examples illustrate the use of implemented tools for the review and curation of annotations of both new and publicly available microbial genomes within MicroScope's rich integrated genome framework. The platform is used as a viewer in order to browse updated annotation information of available microbial genomes (more than 440 organisms to date), and in the context of new annotation projects (117 bacterial genomes). The human expertise gathered in the MicroScope database (about 280,000 independent annotations) contributes to improve the quality of

Genome-Wide Transcription Study of Cryptococcus neoformans H99 Clinical Strain versus Environmental Strains.

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Elaheh Movahed

Full Text Available The infection of Cryptococcus neoformans is acquired through the inhalation of desiccated yeast cells and basidiospores originated from the environment, particularly from bird's droppings and decaying wood. Three environmental strains of C. neoformans originated from bird droppings (H4, S48B and S68B and C. neoformans reference clinical strain (H99 were used for intranasal infection in C57BL/6 mice. We showed that the H99 strain demonstrated higher virulence compared to H4, S48B and S68B strains. To examine if gene expression contributed to the different degree of virulence among these strains, a genome-wide microarray study was performed to inspect the transcriptomic profiles of all four strains. Our results revealed that out of 7,419 genes (22,257 probes examined, 65 genes were significantly up-or down-regulated in H99 versus H4, S48B and S68B strains. The up-regulated genes in H99 strain include Hydroxymethylglutaryl-CoA synthase (MVA1, Mitochondrial matrix factor 1 (MMF1, Bud-site-selection protein 8 (BUD8, High affinity glucose transporter 3 (SNF3 and Rho GTPase-activating protein 2 (RGA2. Pathway annotation using DAVID bioinformatics resource showed that metal ion binding and sugar transmembrane transporter activity pathways were highly expressed in the H99 strain. We suggest that the genes and pathways identified may possibly play crucial roles in the fungal pathogenesis.

PReMod: a database of genome-wide mammalian cis-regulatory module predictions.

Science.gov (United States)

Ferretti, Vincent; Poitras, Christian; Bergeron, Dominique; Coulombe, Benoit; Robert, François; Blanchette, Mathieu

2007-01-01

We describe PReMod, a new database of genome-wide cis-regulatory module (CRM) predictions for both the human and the mouse genomes. The prediction algorithm, described previously in Blanchette et al. (2006) Genome Res., 16, 656-668, exploits the fact that many known CRMs are made of clusters of phylogenetically conserved and repeated transcription factors (TF) binding sites. Contrary to other existing databases, PReMod is not restricted to modules located proximal to genes, but in fact mostly contains distal predicted CRMs (pCRMs). Through its web interface, PReMod allows users to (i) identify pCRMs around a gene of interest; (ii) identify pCRMs that have binding sites for a given TF (or a set of TFs) or (iii) download the entire dataset for local analyses. Queries can also be refined by filtering for specific chromosomal regions, for specific regions relative to genes or for the presence of CpG islands. The output includes information about the binding sites predicted within the selected pCRMs, and a graphical display of their distribution within the pCRMs. It also provides a visual depiction of the chromosomal context of the selected pCRMs in terms of neighboring pCRMs and genes, all of which are linked to the UCSC Genome Browser and the NCBI. PReMod: http://genomequebec.mcgill.ca/PReMod.

DNA Microarrays: a Powerful Genomic Tool for Biomedical and Clinical Research

OpenAIRE

Trevino, Victor; Falciani, Francesco; Barrera-Saldaña, Hugo A

2007-01-01

Among the many benefits of the Human Genome Project are new and powerful tools such as the genome-wide hybridization devices referred to as microarrays. Initially designed to measure gene transcriptional levels, microarray technologies are now used for comparing other genome features among individuals and their tissues and cells. Results provide valuable information on disease subcategories, disease prognosis, and treatment outcome. Likewise, they reveal differences in genetic makeup, regulat...

pcaGoPromoter--an R package for biological and regulatory interpretation of principal components in genome-wide gene expression data

DEFF Research Database (Denmark)

Hansen, Morten; Gerds, Thomas Alexander; Nielsen, Ole Haagen

2012-01-01

Analyzing data obtained from genome-wide gene expression experiments is challenging due to the quantity of variables, the need for multivariate analyses, and the demands of managing large amounts of data. Here we present the R package pcaGoPromoter, which facilitates the interpretation of genome.......g., cell cycle progression and the predicted involvement of expected transcription factors, including E2F. In addition, unexpected results, e.g., cholesterol synthesis in serum-depleted cells and NF-¿B activation in inhibitor treated cells, were noted. In summary, the pcaGoPromoter R package provides...

Genome-wide Analyses Identify KIF5A as a Novel ALS Gene

NARCIS (Netherlands)

Nicolas, Aude; Kenna, Kevin P.; Renton, Alan E.; Ticozzi, Nicola; Faghri, Faraz; Chia, Ruth; Dominov, Janice A.; Kenna, Brendan J.; Nalls, Mike A.; Keagle, Pamela; Rivera, Alberto M.; van Rheenen, Wouter; Murphy, Natalie A.; van Vugt, Joke J.F.A.; Geiger, Joshua T.; van der Spek, Rick; Pliner, Hannah A.; Smith, Bradley N.; Marangi, Giuseppe; Topp, Simon D.; Abramzon, Yevgeniya; Gkazi, Athina Soragia; Eicher, John D.; Kenna, Aoife; Logullo, Francesco O.; Simone, Isabella L.; Logroscino, Giancarlo; Salvi, Fabrizio; Bartolomei, Ilaria; Borghero, Giuseppe; Murru, Maria Rita; Costantino, Emanuela; Pani, Carla; Puddu, Roberta; Caredda, Carla; Piras, Valeria; Tranquilli, Stefania; Cuccu, Stefania; Corongiu, Daniela; Melis, Maurizio; Milia, Antonio; Marrosu, Francesco; Marrosu, Maria Giovanna; Floris, Gianluca; Cannas, Antonino; Capasso, Margherita; Caponnetto, Claudia; Mancardi, Gianluigi; Origone, Paola; Mandich, Paola; Conforti, Francesca L.; Cavallaro, Sebastiano; Mora, Gabriele; Marinou, Kalliopi; Sideri, Riccardo; Penco, Silvana; Mosca, Lorena; Lunetta, Christian; Pinter, Giuseppe Lauria; Corbo, Massimo; Riva, Nilo; Carrera, Paola; Volanti, Paolo; Mandrioli, Jessica; Fini, Nicola; Fasano, Antonio; Tremolizzo, Lucio; Arosio, Alessandro; Ferrarese, Carlo; Trojsi, Francesca; Tedeschi, Gioacchino; Monsurrò, Maria Rosaria; Piccirillo, Giovanni; Femiano, Cinzia; Ticca, Anna; Ortu, Enzo; La Bella, Vincenzo; Spataro, Rossella; Colletti, Tiziana; Sabatelli, Mario; Zollino, Marcella; Conte, Amelia; Luigetti, Marco; Lattante, Serena; Marangi, Giuseppe; Santarelli, Marialuisa; Petrucci, Antonio; Pugliatti, Maura; Pirisi, Angelo; Parish, Leslie D.; Occhineri, Patrizia; Giannini, Fabio; Battistini, Stefania; Ricci, Claudia; Benigni, Michele; Cau, Tea B.; Loi, Daniela; Calvo, Andrea; Moglia, Cristina; Brunetti, Maura; Barberis, Marco; Restagno, Gabriella; Casale, Federico; Marrali, Giuseppe; Fuda, Giuseppe; Ossola, Irene; Cammarosano, Stefania; Canosa, Antonio; Ilardi, Antonio; Manera, Umberto; Grassano, Maurizio; Tanel, Raffaella; Pisano, Fabrizio; Mora, Gabriele; Calvo, Andrea; Mazzini, Letizia; Riva, Nilo; Mandrioli, Jessica; Caponnetto, Claudia; Battistini, Stefania; Volanti, Paolo; La Bella, Vincenzo; Conforti, Francesca L.; Borghero, Giuseppe; Messina, Sonia; Simone, Isabella L.; Trojsi, Francesca; Salvi, Fabrizio; Logullo, Francesco O.; D'Alfonso, Sandra; Corrado, Lucia; Capasso, Margherita; Ferrucci, Luigi; Harms, Matthew B.; Goldstein, David B.; Shneider, Neil A.; Goutman, Stephen A.; Simmons, Zachary; Miller, Timothy M.; Chandran, Siddharthan; Pal, Suvankar; Manousakis, George; Appel, Stanley H.; Simpson, Ericka; Wang, Leo; Baloh, Robert H.; Gibson, Summer B.; Bedlack, Richard; Lacomis, David; Sareen, Dhruv; Sherman, Alexander; Bruijn, Lucie; Penny, Michelle; Moreno, Cristiane de Araujo Martins; Kamalakaran, Sitharthan; Goldstein, David B.; Allen, Andrew S.; Appel, Stanley; Baloh, Robert H.; Bedlack, Richard S.; Boone, Braden E.; Brown, Robert; Carulli, John P.; Chesi, Alessandra; Chung, Wendy K.; Cirulli, Elizabeth T.; Cooper, Gregory M.; Couthouis, Julien; Day-Williams, Aaron G.; Dion, Patrick A.; Gibson, Summer B.; Gitler, Aaron D.; Glass, Jonathan D.; Goldstein, David B.; Han, Yujun; Harms, Matthew B.; Harris, Tim; Hayes, Sebastian D.; Jones, Angela L.; Keebler, Jonathan; Krueger, Brian J.; Lasseigne, Brittany N.; Levy, Shawn E.; Lu, Yi Fan; Maniatis, Tom; McKenna-Yasek, Diane; Miller, Timothy M.; Myers, Richard M.; Petrovski, Slavé; Pulst, Stefan M.; Raphael, Alya R.; Ravits, John M.; Ren, Zhong; Rouleau, Guy A.; Sapp, Peter C.; Shneider, Neil A.; Simpson, Ericka; Sims, Katherine B.; Staropoli, John F.; Waite, Lindsay L.; Wang, Quanli; Wimbish, Jack R.; Xin, Winnie W.; Gitler, Aaron D.; Harris, Tim; Myers, Richard M.; Phatnani, Hemali; Kwan, Justin; Sareen, Dhruv; Broach, James R.; Simmons, Zachary; Arcila-Londono, Ximena; Lee, Edward B.; Van Deerlin, Vivianna M.; Shneider, Neil A.; Fraenkel, Ernest; Ostrow, Lyle W.; Baas, Frank; Zaitlen, Noah; Berry, James D.; Malaspina, Andrea; Fratta, Pietro; Cox, Gregory A.; Thompson, Leslie M.; Finkbeiner, Steve; Dardiotis, Efthimios; Miller, Timothy M.; Chandran, Siddharthan; Pal, Suvankar; Hornstein, Eran; MacGowan, Daniel J.L.; Heiman-Patterson, Terry D.; Hammell, Molly G.; Patsopoulos, Nikolaos A.; Dubnau, Joshua; Nath, Avindra; Phatnani, Hemali; Musunuri, Rajeeva Lochan; Evani, Uday Shankar; Abhyankar, Avinash; Zody, Michael C.; Kaye, Julia; Finkbeiner, Steven; Wyman, Stacia K.; LeNail, Alexander; Lima, Leandro; Fraenkel, Ernest; Rothstein, Jeffrey D.; Svendsen, Clive N.; Thompson, Leslie M.; Van Eyk, Jenny; Maragakis, Nicholas J.; Berry, James D.; Glass, Jonathan D.; Miller, Timothy M.; Kolb, Stephen J.; Baloh, Robert H.; Cudkowicz, Merit; Baxi, Emily; Kaye, Julia; Finkbeiner, Steven; Wyman, Stacia K.; Finkbeiner, Steven; LeNail, Alex; Lima, Leandro; Fraenkel, Ernest; Fraenkel, Ernest; Svendsen, Clive N.; Svendsen, Clive N.; Thompson, Leslie M.; Thompson, Leslie M.; Van Eyk, Jennifer E.; Berry, James D.; Berry, James D.; Miller, Timothy M.; Kolb, Stephen J.; Cudkowicz, Merit; Cudkowicz, Merit; Baxi, Emily; Benatar, Michael; Taylor, J. Paul; Wu, Gang; Rampersaud, Evadnie; Wuu, Joanne; Rademakers, Rosa; Züchner, Stephan; Schule, Rebecca; McCauley, Jacob; Hussain, Sumaira; Cooley, Anne; Wallace, Marielle; Clayman, Christine; Barohn, Richard; Statland, Jeffrey; Ravits, John M.; Swenson, Andrea; Jackson, Carlayne; Trivedi, Jaya; Khan, Shaida; Katz, Jonathan; Jenkins, Liberty; Burns, Ted; Gwathmey, Kelly; Caress, James; McMillan, Corey; Elman, Lauren; Pioro, Erik P.; Heckmann, Jeannine; So, Yuen; Walk, David; Maiser, Samuel; Zhang, Jinghui; Benatar, Michael; Taylor, J. Paul; Taylor, J. Paul; Rampersaud, Evadnie; Wu, Gang; Wuu, Joanne; Silani, Vincenzo; Ticozzi, Nicola; Gellera, Cinzia; Ratti, Antonia; Taroni, Franco; Lauria, Giuseppe; Verde, Federico; Fogh, Isabella; Tiloca, Cinzia; Comi, Giacomo P.; Sorarù, Gianni; Cereda, Cristina; D'Alfonso, Sandra; Corrado, Lucia; De Marchi, Fabiola; Corti, Stefania; Ceroni, Mauro; Mazzini, Letizia; Siciliano, Gabriele; Filosto, Massimiliano; Inghilleri, Maurizio; Peverelli, Silvia; Colombrita, Claudia; Poletti, Barbara; Maderna, Luca; Del Bo, Roberto; Gagliardi, Stella; Querin, Giorgia; Bertolin, Cinzia; Pensato, Viviana; Castellotti, Barbara; Lauria, Giuseppe; Verde, Federico; Fogh, Isabella; Tiloca, Cinzia; Fogh, Isabella; Comi, Giacomo P.; Sorarù, Gianni; Cereda, Cristina; Camu, William; Mouzat, Kevin; Lumbroso, Serge; Corcia, Philippe; Meininger, Vincent; Besson, Gérard; Lagrange, Emmeline; Clavelou, Pierre; Guy, Nathalie; Couratier, Philippe; Vourch, Patrick; Danel, Véronique; Bernard, Emilien; Lemasson, Gwendal; Corcia, Philippe; Laaksovirta, Hannu; Myllykangas, Liisa; Jansson, Lilja; Valori, Miko; Ealing, John; Hamdalla, Hisham; Rollinson, Sara; Pickering-Brown, Stuart; Orrell, Richard W.; Sidle, Katie C.; Malaspina, Andrea; Hardy, John; Singleton, Andrew B.; Johnson, Janel O.; Arepalli, Sampath; Sapp, Peter C.; McKenna-Yasek, Diane; Polak, Meraida; Asress, Seneshaw; Al-Sarraj, Safa; King, Andrew; Troakes, Claire; Vance, Caroline; de Belleroche, Jacqueline; Baas, Frank; ten Asbroek, Anneloor L.M.A.; Muñoz-Blanco, José Luis; Hernandez, Dena G.; Ding, Jinhui; Gibbs, J. Raphael; Scholz, Sonja W.; Scholz, Sonja W.; Floeter, Mary Kay; Campbell, Roy H.; Landi, Francesco; Bowser, Robert; Pulst, Stefan M.; Ravits, John M.; MacGowan, Daniel J.L.; Kirby, Janine; Pioro, Erik P.; Pamphlett, Roger; Broach, James; Gerhard, Glenn; Dunckley, Travis L.; Brady, Christopher B.; Brady, Christopher B.; Kowall, Neil W.; Troncoso, Juan C.; Le Ber, Isabelle; Mouzat, Kevin; Lumbroso, Serge; Mouzat, Kevin; Lumbroso, Serge; Heiman-Patterson, Terry D.; Heiman-Patterson, Terry D.; Kamel, Freya; Van Den Bosch, Ludo; Van Den Bosch, Ludo; Baloh, Robert H.; Strom, Tim M.; Meitinger, Thomas; Strom, Tim M.; Shatunov, Aleksey; Van Eijk, Kristel R.; de Carvalho, Mamede; de Carvalho, Mamede; Kooyman, Maarten; Middelkoop, Bas; Moisse, Matthieu; McLaughlin, Russell; Van Es, Michael A.; Weber, Markus; Boylan, Kevin B.; Van Blitterswijk, Marka; Rademakers, Rosa; Morrison, Karen; Basak, A. Nazli; Mora, Jesús S.; Drory, Vivian; Shaw, Pamela; Turner, Martin R.; Talbot, Kevin; Hardiman, Orla; Williams, Kelly L.; Fifita, Jennifer A.; Nicholson, Garth A.; Blair, Ian P.; Nicholson, Garth A.; Rouleau, Guy A.; Esteban-Pérez, Jesús; García-Redondo, Alberto; Al-Chalabi, Ammar; Al Kheifat, Ahmad; Al-Chalabi, Ammar; Andersen, Peter M.; Basak, A. Nazli; Blair, Ian P.; Chio, Adriano; Cooper-Knock, Jonathan; Corcia, Philippe; Couratier, Philippe; de Carvalho, Mamede; Dekker, Annelot; Drory, Vivian; Redondo, Alberto Garcia; Gotkine, Marc; Hardiman, Orla; Hide, Winston; Iacoangeli, Alfredo; Glass, Jonathan D.; Kenna, Kevin P.; Kiernan, Matthew; Kooyman, Maarten; Landers, John E.; McLaughlin, Russell; Middelkoop, Bas; Mill, Jonathan; Neto, Miguel Mitne; Moisse, Matthieu; Pardina, Jesus Mora; Morrison, Karen; Newhouse, Stephen; Pinto, Susana; Pulit, Sara; Robberecht, Wim; Shatunov, Aleksey; Shaw, Pamela; Shaw, Chris; Silani, Vincenzo; Sproviero, William; Tazelaar, Gijs; Ticozzi, Nicola; Van Damme, Philip; van den Berg, Leonard; van der Spek, Rick; Van Eijk, Kristel R.; Van Es, Michael A.; van Rheenen, Wouter; van Vugt, Joke J.F.A.; Veldink, Jan H.; Weber, Markus; Williams, Kelly L.; Van Damme, Philip; Robberecht, Wim; Zatz, Mayana; Robberecht, Wim; Bauer, Denis C.; Twine, Natalie A.; Rogaeva, Ekaterina; Zinman, Lorne; Ostrow, Lyle W.; Maragakis, Nicholas J.; Rothstein, Jeffrey D.; Simmons, Zachary; Cooper-Knock, Johnathan; Brice, Alexis; Goutman, Stephen A.; Feldman, Eva L.; Gibson, Summer B.; Taroni, Franco; Ratti, Antonia; Ratti, Antonia; Gellera, Cinzia; Van Damme, Philip; Robberecht, Wim; Fratta, Pietro; Sabatelli, Mario; Lunetta, Christian; Ludolph, Albert C.; Andersen, Peter M.; Weishaupt, Jochen H.; Camu, William; Trojanowski, John Q.; Van Deerlin, Vivianna M.; Brown, Robert H.; van den Berg, Leonard; Veldink, Jan H.; Harms, Matthew B.; Glass, Jonathan D.; Stone, David J.; Tienari, Pentti; Silani, Vincenzo; Silani, Vincenzo; Chiò, Adriano; Shaw, Christopher E.; Chiò, Adriano; Traynor, Bryan J.; Landers, John E.; Traynor, Bryan J.

2018-01-01

To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494

From the Beauty of Genomic Landscapes to the Strength of Transcriptional Mechanisms.

Science.gov (United States)

Natoli, Gioacchino

2016-03-24

Genomic analyses are commonly used to infer trends and broad rules underlying transcriptional control. The innovative approach by Tong et al. to interrogate genomic datasets allows extracting mechanistic information on the specific regulation of individual genes. Copyright © 2016 Elsevier Inc. All rights reserved.

Novel transcripts discovered by mining genomic DNA from defined regions of bovine chromosome 6

Directory of Open Access Journals (Sweden)

Eberlein Annett

2009-04-01

Full Text Available Abstract Background Linkage analyses strongly suggest a number of QTL for production, health and conformation traits in the middle part of bovine chromosome 6 (BTA6. The identification of the molecular background underlying the genetic variation at the QTL and subsequent functional studies require a well-annotated gene sequence map of the critical QTL intervals. To complete the sequence map of the defined subchromosomal regions on BTA6 poorly covered with comparative gene information, we focused on targeted isolation of transcribed sequences from bovine bacterial artificial chromosome (BAC clones mapped to the QTL intervals. Results Using the method of exon trapping, 92 unique exon trapping sequences (ETS were discovered in a chromosomal region of poor gene coverage. Sequence identity to the current NCBI sequence assembly for BTA6 was detected for 91% of unique ETS. Comparative sequence similarity search revealed that 11% of the isolated ETS displayed high similarity to genomic sequences located on the syntenic chromosomes of the human and mouse reference genome assemblies. Nearly a third of the ETS identified similar equivalent sequences in genomic sequence scaffolds from the alternative Celera-based sequence assembly of the human genome. Screening gene, EST, and protein databases detected 17% of ETS with identity to known transcribed sequences. Expression analysis of a subset of the ETS showed that most ETS (84% displayed a distinctive expression pattern in a multi-tissue panel of a lactating cow verifying their existence in the bovine transcriptome. Conclusion The results of our study demonstrate that the exon trapping method based on region-specific BAC clones is very useful for targeted screening for novel transcripts located within a defined chromosomal region being deficiently endowed with annotated gene information. The majority of identified ETS represents unknown noncoding sequences in intergenic regions on BTA6 displaying a

Sandwich corrected standard errors in family-based genome-wide association studies

NARCIS (Netherlands)

Minica, C.C.; Dolan, C.V.; Kampert, M.M.D.; Boomsma, D.I.; Vink, J.M.

2015-01-01

Given the availability of genotype and phenotype data collected in family members, the question arises which estimator ensures the most optimal use of such data in genome-wide scans. Using simulations, we compared the Unweighted Least Squares (ULS) and Maximum Likelihood (ML) procedures. The former

Genome Wide Identification of Orthologous ZIP Genes Associated with Zinc and Iron Translocation in Setaria italica.

Science.gov (United States)

Alagarasan, Ganesh; Dubey, Mahima; Aswathy, Kumar S; Chandel, Girish

2017-01-01

Genes in the ZIP family encode transcripts to store and transport bivalent metal micronutrient, particularly iron (Fe) and or zinc (Zn). These transcripts are important for a variety of functions involved in the developmental and physiological processes in many plant species, including most, if not all, Poaceae plant species and the model species Arabidopsis. Here, we present the report of a genome wide investigation of orthologous ZIP genes in Setaria italica and the identification of 7 single copy genes. RT-PCR shows 4 of them could be used to increase the bio-availability of zinc and iron content in grains. Of 36 ZIP members, 25 genes have traces of signal peptide based sub-cellular localization, as compared to those of plant species studied previously, yet translocation of ions remains unclear. In silico analysis of gene structure and protein nature suggests that these two were preeminent in shaping the functional diversity of the ZIP gene family in S. italica . NAC, bZIP and bHLH are the predominant Fe and Zn responsive transcription factors present in SiZIP genes. Together, our results provide new insights into the signal peptide based/independent iron and zinc translocation in the plant system and allowed identification of ZIP genes that may be involved in the zinc and iron absorption from the soil, and thus transporting it to the cereal grain underlying high micronutrient accumulation.

Maternal experience with predation risk influences genome-wide embryonic gene expression in threespined sticklebacks (Gasterosteus aculeatus).

Science.gov (United States)

Mommer, Brett C; Bell, Alison M

2014-01-01

There is growing evidence for nongenetic effects of maternal experience on offspring. For example, previous studies have shown that female threespined stickleback fish (Gasterosteus aculeatus) exposed to predation risk produce offspring with altered behavior, metabolism and stress physiology. Here, we investigate the effect of maternal exposure to predation risk on the embryonic transcriptome in sticklebacks. Using RNA-sequencing we compared genome-wide transcription in three day post-fertilization embryos of predator-exposed and control mothers. There were hundreds of differentially expressed transcripts between embryos of predator-exposed mothers and embryos of control mothers including several non-coding RNAs. Gene Ontology analysis revealed biological pathways involved in metabolism, epigenetic inheritance, and neural proliferation and differentiation that differed between treatments. Interestingly, predation risk is associated with an accelerated life history in many vertebrates, and several of the genes and biological pathways that were identified in this study suggest that maternal exposure to predation risk accelerates the timing of embryonic development. Consistent with this hypothesis, embryos of predator-exposed mothers were larger than embryos of control mothers. These findings point to some of the molecular mechanisms that might underlie maternal effects.

Maternal experience with predation risk influences genome-wide embryonic gene expression in threespined sticklebacks (Gasterosteus aculeatus.

Directory of Open Access Journals (Sweden)

Brett C Mommer

Full Text Available There is growing evidence for nongenetic effects of maternal experience on offspring. For example, previous studies have shown that female threespined stickleback fish (Gasterosteus aculeatus exposed to predation risk produce offspring with altered behavior, metabolism and stress physiology. Here, we investigate the effect of maternal exposure to predation risk on the embryonic transcriptome in sticklebacks. Using RNA-sequencing we compared genome-wide transcription in three day post-fertilization embryos of predator-exposed and control mothers. There were hundreds of differentially expressed transcripts between embryos of predator-exposed mothers and embryos of control mothers including several non-coding RNAs. Gene Ontology analysis revealed biological pathways involved in metabolism, epigenetic inheritance, and neural proliferation and differentiation that differed between treatments. Interestingly, predation risk is associated with an accelerated life history in many vertebrates, and several of the genes and biological pathways that were identified in this study suggest that maternal exposure to predation risk accelerates the timing of embryonic development. Consistent with this hypothesis, embryos of predator-exposed mothers were larger than embryos of control mothers. These findings point to some of the molecular mechanisms that might underlie maternal effects.

Transcription profile of Escherichia coli: genomic SELEX search for regulatory targets of transcription factors.

Science.gov (United States)

Ishihama, Akira; Shimada, Tomohiro; Yamazaki, Yukiko

2016-03-18

Bacterial genomes are transcribed by DNA-dependent RNA polymerase (RNAP), which achieves gene selectivity through interaction with sigma factors that recognize promoters, and transcription factors (TFs) that control the activity and specificity of RNAP holoenzyme. To understand the molecular mechanisms of transcriptional regulation, the identification of regulatory targets is needed for all these factors. We then performed genomic SELEX screenings of targets under the control of each sigma factor and each TF. Here we describe the assembly of 156 SELEX patterns of a total of 116 TFs performed in the presence and absence of effector ligands. The results reveal several novel concepts: (i) each TF regulates more targets than hitherto recognized; (ii) each promoter is regulated by more TFs than hitherto recognized; and (iii) the binding sites of some TFs are located within operons and even inside open reading frames. The binding sites of a set of global regulators, including cAMP receptor protein, LeuO and Lrp, overlap with those of the silencer H-NS, suggesting that certain global regulators play an anti-silencing role. To facilitate sharing of these accumulated SELEX datasets with the research community, we compiled a database, 'Transcription Profile of Escherichia coli' (www.shigen.nig.ac.jp/ecoli/tec/). © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Genome-wide differential gene expression in children exposed to air pollution in the Czech Republic

DEFF Research Database (Denmark)

van Leeuwen, D M; van Herwijnen, M H M; Pedersen, Marie

2006-01-01

The Teplice area in the Czech Republic is a mining district where elevated levels of air pollution including airborne carcinogens, have been demonstrated, especially during winter time. This environmental exposure can impact human health; in particular children may be more vulnerable. To study....... This suggests an effect of air pollution on the primary structural unit of the condensed DNA. In addition, several other pathways were modulated. Based on the results of this study, we suggest that transcriptomic analysis represents a promising biomarker for environmental carcinogenesis....... the impact of air pollution in children at the transcriptional level, peripheral blood cells were subjected to whole genome response analysis, in order to identify significantly modulated biological pathways and processes as a result of exposure. Using genome-wide oligonucleotide microarrays, we investigated...

Genome-wide screening and identification of antigens for rickettsial vaccine development

Science.gov (United States)

The capacity to identify immunogens for vaccine development by genome-wide screening has been markedly enhanced by the availability of complete microbial genome sequences coupled to rapid proteomic and bioinformatic analysis. Critical to this genome-wide screening is in vivo testing in the context o...

Genome-wide identification and characterization of R2R3MYB family in Rosaceae.

Science.gov (United States)

González, Máximo; Carrasco, Basilio; Salazar, Erika

2016-09-01

Transcription factors R2R3MYB family have been associated with the control of secondary metabolites, development of structures, cold tolerance and response to biotic and abiotic stress, among others. In recent years, genomes of Rosaceae botanical family are available. Although this information has been used to study the karyotype evolution of these species from an ancestral genome, there are no studies that treat the evolution and diversity of gene families present in these species or in the botanical family. Here we present the first comparative study of the R2R3MYB subfamily of transcription factors in three species of Rosaceae family (Malus domestica, Prunus persica and Fragaria vesca). We described 186, 98 and 86 non-redundant gene models for apple, peach and strawberry, respectively. In this research, we analyzed the intron-exon structure and genomic distribution of R2R3MYB families mentioned above. The phylogenetic comparisons revealed putative functions of some R2R3MYB transcription factors. This analysis found 44 functional subgroups, seven of which were unique for Rosaceae. In addition, our results showed a highly collinearity among some genes revealing the existence of conserved gene models between the three species studied. Although some gene models in these species have been validated under several approaches, more research in the Rosaceae family is necessary to determine gene expression patterns in specific tissues and development stages to facilitate understanding of the regulatory and biochemical mechanism in this botanical family.

Chromatin immunoprecipitation (ChIP) of plant transcription factors followed by sequencing (ChIP-SEQ) or hybridization to whole genome arrays (ChIP-CHIP)

NARCIS (Netherlands)

Kaufmann, K.; Muiño, J.M.; Østerås, M.; Farinelli, L.; Krajewski, P.; Angenent, G.C.

2010-01-01

Chromatin immunoprecipitation (ChIP) is a powerful technique to study interactions between transcription factors (TFs) and DNA in vivo. For genome-wide de novo discovery of TF-binding sites, the DNA that is obtained in ChIP experiments needs to be processed for sequence identification. The sequences

A genome-wide longitudinal transcriptome analysis of the aging model Podospora anserina.

Science.gov (United States)

Philipp, Oliver; Hamann, Andrea; Servos, Jörg; Werner, Alexandra; Koch, Ina; Osiewacz, Heinz D

2013-01-01

Aging of biological systems is controlled by various processes which have a potential impact on gene expression. Here we report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina. Total RNA of three individuals of defined age were pooled and analyzed by SuperSAGE (serial analysis of gene expression). A bioinformatics analysis identified different molecular pathways to be affected during aging. While the abundance of transcripts linked to ribosomes and to the proteasome quality control system were found to decrease during aging, those associated with autophagy increase, suggesting that autophagy may act as a compensatory quality control pathway. Transcript profiles associated with the energy metabolism including mitochondrial functions were identified to fluctuate during aging. Comparison of wild-type transcripts, which are continuously down-regulated during aging, with those down-regulated in the long-lived, copper-uptake mutant grisea, validated the relevance of age-related changes in cellular copper metabolism. Overall, we (i) present a unique age-related data set of a longitudinal study of the experimental aging model P. anserina which represents a reference resource for future investigations in a variety of organisms, (ii) suggest autophagy to be a key quality control pathway that becomes active once other pathways fail, and (iii) present testable predictions for subsequent experimental investigations.

A genome-wide longitudinal transcriptome analysis of the aging model Podospora anserina.

Directory of Open Access Journals (Sweden)

Oliver Philipp

Full Text Available Aging of biological systems is controlled by various processes which have a potential impact on gene expression. Here we report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina. Total RNA of three individuals of defined age were pooled and analyzed by SuperSAGE (serial analysis of gene expression. A bioinformatics analysis identified different molecular pathways to be affected during aging. While the abundance of transcripts linked to ribosomes and to the proteasome quality control system were found to decrease during aging, those associated with autophagy increase, suggesting that autophagy may act as a compensatory quality control pathway. Transcript profiles associated with the energy metabolism including mitochondrial functions were identified to fluctuate during aging. Comparison of wild-type transcripts, which are continuously down-regulated during aging, with those down-regulated in the long-lived, copper-uptake mutant grisea, validated the relevance of age-related changes in cellular copper metabolism. Overall, we (i present a unique age-related data set of a longitudinal study of the experimental aging model P. anserina which represents a reference resource for future investigations in a variety of organisms, (ii suggest autophagy to be a key quality control pathway that becomes active once other pathways fail, and (iii present testable predictions for subsequent experimental investigations.

A genome-wide association study identifies protein quantitative trait loci (pQTLs.

Directory of Open Access Journals (Sweden)

David Melzer

2008-05-01

Full Text Available There is considerable evidence that human genetic variation influences gene expression. Genome-wide studies have revealed that mRNA levels are associated with genetic variation in or close to the gene coding for those mRNA transcripts - cis effects, and elsewhere in the genome - trans effects. The role of genetic variation in determining protein levels has not been systematically assessed. Using a genome-wide association approach we show that common genetic variation influences levels of clinically relevant proteins in human serum and plasma. We evaluated the role of 496,032 polymorphisms on levels of 42 proteins measured in 1200 fasting individuals from the population based InCHIANTI study. Proteins included insulin, several interleukins, adipokines, chemokines, and liver function markers that are implicated in many common diseases including metabolic, inflammatory, and infectious conditions. We identified eight Cis effects, including variants in or near the IL6R (p = 1.8x10(-57, CCL4L1 (p = 3.9x10(-21, IL18 (p = 6.8x10(-13, LPA (p = 4.4x10(-10, GGT1 (p = 1.5x10(-7, SHBG (p = 3.1x10(-7, CRP (p = 6.4x10(-6 and IL1RN (p = 7.3x10(-6 genes, all associated with their respective protein products with effect sizes ranging from 0.19 to 0.69 standard deviations per allele. Mechanisms implicated include altered rates of cleavage of bound to unbound soluble receptor (IL6R, altered secretion rates of different sized proteins (LPA, variation in gene copy number (CCL4L1 and altered transcription (GGT1. We identified one novel trans effect that was an association between ABO blood group and tumour necrosis factor alpha (TNF-alpha levels (p = 6.8x10(-40, but this finding was not present when TNF-alpha was measured using a different assay , or in a second study, suggesting an assay-specific association. Our results show that protein levels share some of the features of the genetics of gene expression. These include the presence of strong genetic effects in cis

Quality control and conduct of genome-wide association meta-analyses

DEFF Research Database (Denmark)

Winkler, Thomas W; Day, Felix R; Croteau-Chonka, Damien C

2014-01-01

Rigorous organization and quality control (QC) are necessary to facilitate successful genome-wide association meta-analyses (GWAMAs) of statistics aggregated across multiple genome-wide association studies. This protocol provides guidelines for (i) organizational aspects of GWAMAs, and for (ii) QC...

Genome-wide association study of pathological gambling.

Science.gov (United States)

Lang, M; Leménager, T; Streit, F; Fauth-Bühler, M; Frank, J; Juraeva, D; Witt, S H; Degenhardt, F; Hofmann, A; Heilmann-Heimbach, S; Kiefer, F; Brors, B; Grabe, H-J; John, U; Bischof, A; Bischof, G; Völker, U; Homuth, G; Beutel, M; Lind, P A; Medland, S E; Slutske, W S; Martin, N G; Völzke, H; Nöthen, M M; Meyer, C; Rumpf, H-J; Wurst, F M; Rietschel, M; Mann, K F

2016-08-01

Pathological gambling is a behavioural addiction with negative economic, social, and psychological consequences. Identification of contributing genes and pathways may improve understanding of aetiology and facilitate therapy and prevention. Here, we report the first genome-wide association study of pathological gambling. Our aims were to identify pathways involved in pathological gambling, and examine whether there is a genetic overlap between pathological gambling and alcohol dependence. Four hundred and forty-five individuals with a diagnosis of pathological gambling according to the Diagnostic and Statistical Manual of Mental Disorders were recruited in Germany, and 986 controls were drawn from a German general population sample. A genome-wide association study of pathological gambling comprising single marker, gene-based, and pathway analyses, was performed. Polygenic risk scores were generated using data from a German genome-wide association study of alcohol dependence. No genome-wide significant association with pathological gambling was found for single markers or genes. Pathways for Huntington's disease (P-value=6.63×10(-3)); 5'-adenosine monophosphate-activated protein kinase signalling (P-value=9.57×10(-3)); and apoptosis (P-value=1.75×10(-2)) were significant. Polygenic risk score analysis of the alcohol dependence dataset yielded a one-sided nominal significant P-value in subjects with pathological gambling, irrespective of comorbid alcohol dependence status. The present results accord with previous quantitative formal genetic studies which showed genetic overlap between non-substance- and substance-related addictions. Furthermore, pathway analysis suggests shared pathology between Huntington's disease and pathological gambling. This finding is consistent with previous imaging studies. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

High-resolution transcription atlas of the mitotic cell cycle in budding yeast

DEFF Research Database (Denmark)

Granovskaia, Marina V; Jensen, Lars J; Ritchie, Matthew E

2010-01-01

Extensive transcription of non-coding RNAs has been detected in eukaryotic genomes and is thought to constitute an additional layer in the regulation of gene expression. Despite this role, their transcription through the cell cycle has not been studied; genome-wide approaches have only focused on...

Elucidating the transcription cycle of the UV-inducible hyperthermophilic archaeal virus SSV1 by DNA microarrays

International Nuclear Information System (INIS)

Froels, Sabrina; Gordon, Paul M.K.; Panlilio, Mayi Arcellana; Schleper, Christa; Sensen, Christoph W.

2007-01-01

The spindle-shaped Sulfolobus virus SSV1 was the first of a series of unusual and uniquely shaped viruses isolated from hyperthermophilic Archaea. Using whole-genome microarrays we show here that the circular 15.5 kb DNA genome of SSV1 exhibits a chronological regulation of its transcription upon UV irradiation, reminiscent to the life cycles of bacteriophages and eukaryotic viruses. The transcriptional cycle starts with a small UV-specific transcript and continues with early transcripts on both its flanks. The late transcripts appear after the onset of viral replication and are extended to their full lengths towards the end of the approximately 8.5 h cycle. While we detected only small differences in genome-wide analysis of the host Sulfolobus solfataricus comparing infected versus uninfected strains, we found a marked difference with respect to the strength and speed of the general UV response of the host. Models for the regulation of the virus cycle, and putative functions of genes in SSV1 are presented

Genome-wide identification of significant aberrations in cancer genome

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Yuan Xiguo

2012-07-01

Full Text Available Abstract Background Somatic Copy Number Alterations (CNAs in human genomes are present in almost all human cancers. Systematic efforts to characterize such structural variants must effectively distinguish significant consensus events from random background aberrations. Here we introduce Significant Aberration in Cancer (SAIC, a new method for characterizing and assessing the statistical significance of recurrent CNA units. Three main features of SAIC include: (1 exploiting the intrinsic correlation among consecutive probes to assign a score to each CNA unit instead of single probes; (2 performing permutations on CNA units that preserve correlations inherent in the copy number data; and (3 iteratively detecting Significant Copy Number Aberrations (SCAs and estimating an unbiased null distribution by applying an SCA-exclusive permutation scheme. Results We test and compare the performance of SAIC against four peer methods (GISTIC, STAC, KC-SMART, CMDS on a large number of simulation datasets. Experimental results show that SAIC outperforms peer methods in terms of larger area under the Receiver Operating Characteristics curve and increased detection power. We then apply SAIC to analyze structural genomic aberrations acquired in four real cancer genome-wide copy number data sets (ovarian cancer, metastatic prostate cancer, lung adenocarcinoma, glioblastoma. When compared with previously reported results, SAIC successfully identifies most SCAs known to be of biological significance and associated with oncogenes (e.g., KRAS, CCNE1, and MYC or tumor suppressor genes (e.g., CDKN2A/B. Furthermore, SAIC identifies a number of novel SCAs in these copy number data that encompass tumor related genes and may warrant further studies. Conclusions Supported by a well-grounded theoretical framework, SAIC has been developed and used to identify SCAs in various cancer copy number data sets, providing useful information to study the landscape of cancer genomes

Distinct Contributions of Replication and Transcription to Mutation Rate Variation of Human Genomes

KAUST Repository

Cui, Peng; Ding, Feng; Lin, Qiang; Zhang, Lingfang; Li, Ang; Zhang, Zhang; Hu, Songnian; Yu, Jun

2012-01-01

Here, we evaluate the contribution of two major biological processes—DNA replication and transcription—to mutation rate variation in human genomes. Based on analysis of the public human tissue transcriptomics data, high-resolution replicating map of Hela cells and dbSNP data, we present significant correlations between expression breadth, replication time in local regions and SNP density. SNP density of tissue-specific (TS) genes is significantly higher than that of housekeeping (HK) genes. TS genes tend to locate in late-replicating genomic regions and genes in such regions have a higher SNP density compared to those in early-replication regions. In addition, SNP density is found to be positively correlated with expression level among HK genes. We conclude that the process of DNA replication generates stronger mutational pressure than transcription-associated biological processes do, resulting in an increase of mutation rate in TS genes while having weaker effects on HK genes. In contrast, transcription-associated processes are mainly responsible for the accumulation of mutations in highly-expressed HK genes.

Distinct Contributions of Replication and Transcription to Mutation Rate Variation of Human Genomes

KAUST Repository

Cui, Peng

2012-03-23

Here, we evaluate the contribution of two major biological processes—DNA replication and transcription—to mutation rate variation in human genomes. Based on analysis of the public human tissue transcriptomics data, high-resolution replicating map of Hela cells and dbSNP data, we present significant correlations between expression breadth, replication time in local regions and SNP density. SNP density of tissue-specific (TS) genes is significantly higher than that of housekeeping (HK) genes. TS genes tend to locate in late-replicating genomic regions and genes in such regions have a higher SNP density compared to those in early-replication regions. In addition, SNP density is found to be positively correlated with expression level among HK genes. We conclude that the process of DNA replication generates stronger mutational pressure than transcription-associated biological processes do, resulting in an increase of mutation rate in TS genes while having weaker effects on HK genes. In contrast, transcription-associated processes are mainly responsible for the accumulation of mutations in highly-expressed HK genes.

Comprehensive analysis of genome-wide DNA methylation across human polycystic ovary syndrome ovary granulosa cell.

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Xu, Jiawei; Bao, Xiao; Peng, Zhaofeng; Wang, Linlin; Du, Linqing; Niu, Wenbin; Sun, Yingpu

2016-05-10

Polycystic ovary syndrome (PCOS) affects approximately 7% of the reproductive-age women. A growing body of evidence indicated that epigenetic mechanisms contributed to the development of PCOS. The role of DNA modification in human PCOS ovary granulosa cell is still unknown in PCOS progression. Global DNA methylation and hydroxymethylation were detected between PCOS' and controls' granulosa cell. Genome-wide DNA methylation was profiled to investigate the putative function of DNA methylaiton. Selected genes expressions were analyzed between PCOS' and controls' granulosa cell. Our results showed that the granulosa cell global DNA methylation of PCOS patients was significant higher than the controls'. The global DNA hydroxymethylation showed low level and no statistical difference between PCOS and control. 6936 differentially methylated CpG sites were identified between control and PCOS-obesity. 12245 differential methylated CpG sites were detected between control and PCOS-nonobesity group. 5202 methylated CpG sites were significantly differential between PCOS-obesity and PCOS-nonobesity group. Our results showed that DNA methylation not hydroxymethylation altered genome-wide in PCOS granulosa cell. The different methylation genes were enriched in development protein, transcription factor activity, alternative splicing, sequence-specific DNA binding and embryonic morphogenesis. YWHAQ, NCF2, DHRS9 and SCNA were up-regulation in PCOS-obesity patients with no significance different between control and PCOS-nonobesity patients, which may be activated by lower DNA methylaiton. Global and genome-wide DNA methylation alteration may contribute to different genes expression and PCOS clinical pathology.

eRNAs promote transcription by establishing chromatin accessibility at defined genomic loci

DEFF Research Database (Denmark)

Mousavi, Kambiz; Zare, Hossein; Dell'orso, Stefania

2013-01-01

)RNA acted to activate the downstream myogenic genes. The deployment of transcriptional machinery to appropriate loci is contingent on chromatin accessibility, a rate-limiting step preceding Pol II assembly. By nuclease sensitivity assay, we found that eRNAs regulate genomic access of the transcriptional...... complex to defined regulatory regions. In conclusion, our data suggest that eRNAs contribute to establishing a cell-type-specific transcriptional circuitry by directing chromatin-remodeling events....

Integrative Genomics Reveals Mechanisms of Copy Number Alterations Responsible for Transcriptional Deregulation in Colorectal Cancer

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Camps, Jordi; Nguyen, Quang Tri; Padilla-Nash, Hesed M.; Knutsen, Turid; McNeil, Nicole E.; Wangsa, Danny; Hummon, Amanda B.; Grade, Marian; Ried, Thomas; Difilippantonio, Michael J.

2016-01-01

To evaluate the mechanisms and consequences of chromosomal aberrations in colorectal cancer (CRC), we used a combination of spectral karyotyping, array comparative genomic hybridization (aCGH), and array-based global gene expression profiling on 31 primary carcinomas and 15 established cell lines. Importantly, aCGH showed that the genomic profiles of primary tumors are recapitulated in the cell lines. We revealed a preponderance of chromosome breakpoints at sites of copy number variants (CNVs) in the CRC cell lines, a novel mechanism of DNA breakage in cancer. The integration of gene expression and aCGH led to the identification of 157 genes localized within high-level copy number changes whose transcriptional deregulation was significantly affected across all of the samples, thereby suggesting that these genes play a functional role in CRC. Genomic amplification at 8q24 was the most recurrent event and led to the overexpression of MYC and FAM84B. Copy number dependent gene expression resulted in deregulation of known cancer genes such as APC, FGFR2, and ERBB2. The identification of only 36 genes whose localization near a breakpoint could account for their observed deregulated expression demonstrates that the major mechanism for transcriptional deregulation in CRC is genomic copy number changes resulting from chromosomal aberrations. PMID:19691111

Genome-wide transcriptional responses to carbon starvation in nongrowing Lactococcus lactis

NARCIS (Netherlands)

Ercan, O.; Wels, M.; Smid, E.J.; Kleerebezem, M.

2015-01-01

This paper describes the transcriptional adaptations of nongrowing, retentostat cultures of Lactococcus lactis to starvation. Near-zero-growth cultures (µ = 0.0001 h-1) obtained by extended retentostat cultivation were exposed to starvation by termination of the medium supply for 24 h, followed by a

The genomes and comparative genomics of Lactobacillus delbrueckii phages.

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Riipinen, Katja-Anneli; Forsman, Päivi; Alatossava, Tapani

2011-07-01

Lactobacillus delbrueckii phages are a great source of genetic diversity. Here, the genome sequences of Lb. delbrueckii phages LL-Ku, c5 and JCL1032 were analyzed in detail, and the genetic diversity of Lb. delbrueckii phages belonging to different taxonomic groups was explored. The lytic isometric group b phages LL-Ku (31,080 bp) and c5 (31,841 bp) showed a minimum nucleotide sequence identity of 90% over about three-fourths of their genomes. The genomic locations of their lysis modules were unique, and the genomes featured several putative overlapping transcription units of genes. LL-Ku and c5 virions displayed peptidoglycan hydrolytic activity associated with a ~36-kDa protein similar in size to the endolysin. Unexpectedly, the 49,433-bp genome of the prolate phage JCL1032 (temperate, group c) revealed a conserved gene order within its structural genes. Lb. delbrueckii phages representing groups a (a phage LL-H), b and c possessed only limited protein sequence homology. Genomic comparison of LL-Ku and c5 suggested that diversification of Lb. delbrueckii phages is mainly due to insertions, deletions and recombination. For the first time, the complete genome sequences of group b and c Lb. delbrueckii phages are reported.

Genome-wide analysis of the AP2/ERF family in Musa species reveals divergence and neofunctionalisation during evolution.

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Lakhwani, Deepika; Pandey, Ashutosh; Dhar, Yogeshwar Vikram; Bag, Sumit Kumar; Trivedi, Prabodh Kumar; Asif, Mehar Hasan

2016-01-06

AP2/ERF domain containing transcription factor super family is one of the important regulators in the plant kingdom. The involvement of AP2/ERF family members has been elucidated in various processes associated with plant growth, development as well as in response to hormones, biotic and abiotic stresses. In this study, we carried out genome-wide analysis to identify members of AP2/ERF family in Musa acuminata (A genome) and Musa balbisiana (B genome) and changes leading to neofunctionalisation of genes. Analysis identified 265 and 318 AP2/ERF encoding genes in M. acuminata and M. balbisiana respectively which were further classified into ERF, DREB, AP2, RAV and Soloist groups. Comparative analysis indicated that AP2/ERF family has undergone duplication, loss and divergence during evolution and speciation of the Musa A and B genomes. We identified nine genes which are up-regulated during fruit ripening and might be components of the regulatory machinery operating during ethylene-dependent ripening in banana. Tissue-specific expression analysis of the genes suggests that different regulatory mechanisms might be involved in peel and pulp ripening process through recruiting specific ERFs in these tissues. Analysis also suggests that MaRAV-6 and MaERF026 have structurally diverged from their M. balbisiana counterparts and have attained new functions during ripening.

Comparative Genomics of Carp Herpesviruses

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Kurobe, Tomofumi; Gatherer, Derek; Cunningham, Charles; Korf, Ian; Fukuda, Hideo; Hedrick, Ronald P.; Waltzek, Thomas B.

2013-01-01

Three alloherpesviruses are known to cause disease in cyprinid fish: cyprinid herpesviruses 1 and 3 (CyHV1 and CyHV3) in common carp and koi and cyprinid herpesvirus 2 (CyHV2) in goldfish. We have determined the genome sequences of CyHV1 and CyHV2 and compared them with the published CyHV3 sequence. The CyHV1 and CyHV2 genomes are 291,144 and 290,304 bp, respectively, in size, and thus the CyHV3 genome, at 295,146 bp, remains the largest recorded among the herpesviruses. Each of the three genomes consists of a unique region flanked at each terminus by a sizeable direct repeat. The CyHV1, CyHV2, and CyHV3 genomes are predicted to contain 137, 150, and 155 unique, functional protein-coding genes, respectively, of which six, four, and eight, respectively, are duplicated in the terminal repeat. The three viruses share 120 orthologous genes in a largely colinear arrangement, of which up to 55 are also conserved in the other member of the genus Cyprinivirus, anguillid herpesvirus 1. Twelve genes are conserved convincingly in all sequenced alloherpesviruses, and two others are conserved marginally. The reference CyHV3 strain has been reported to contain five fragmented genes that are presumably nonfunctional. The CyHV2 strain has two fragmented genes, and the CyHV1 strain has none. CyHV1, CyHV2, and CyHV3 have five, six, and five families of paralogous genes, respectively. One family unique to CyHV1 is related to cellular JUNB, which encodes a transcription factor involved in oncogenesis. To our knowledge, this is the first time that JUNB-related sequences have been reported in a herpesvirus. PMID:23269803

A genome-wide gene expression signature of environmental geography in leukocytes of Moroccan Amazighs.

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Youssef Idaghdour

2008-04-01

Full Text Available The different environments that humans experience are likely to impact physiology and disease susceptibility. In order to estimate the magnitude of the impact of environment on transcript abundance, we examined gene expression in peripheral blood leukocyte samples from 46 desert nomadic, mountain agrarian and coastal urban Moroccan Amazigh individuals. Despite great expression heterogeneity in humans, as much as one third of the leukocyte transcriptome was found to be associated with differences among regions. Genome-wide polymorphism analysis indicates that genetic differentiation in the total sample is limited and is unlikely to explain the expression divergence. Methylation profiling of 1,505 CpG sites suggests limited contribution of methylation to the observed differences in gene expression. Genetic network analysis further implies that specific aspects of immune function are strongly affected by regional factors and may influence susceptibility to respiratory and inflammatory disease. Our results show a strong genome-wide gene expression signature of regional population differences that presumably include lifestyle, geography, and biotic factors, implying that these can play at least as great a role as genetic divergence in modulating gene expression variation in humans.

Genome-wide Association Study Implicates PARD3B-based AIDS Restriction

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Nelson, George W.; Lautenberger, James A.; Chinn, Leslie; McIntosh, Carl; Johnson, Randall C.; Sezgin, Efe; Kessing, Bailey; Malasky, Michael; Hendrickson, Sher L.; Pontius, Joan; Tang, Minzhong; An, Ping; Winkler, Cheryl A.; Limou, Sophie; Le Clerc, Sigrid; Delaneau, Olivier; Zagury, Jean-François; Schuitemaker, Hanneke; van Manen, Daniëlle; Bream, Jay H.; Gomperts, Edward D.; Buchbinder, Susan; Goedert, James J.; Kirk, Gregory D.; O'Brien, Stephen J.

2011-01-01

Background. Host genetic variation influences human immunodeficiency virus (HIV) infection and progression to AIDS. Here we used clinically well-characterized subjects from 5 pretreatment HIV/AIDS cohorts for a genome-wide association study to identify gene associations with rate of AIDS progression. Methods.  European American HIV seroconverters (n = 755) were interrogated for single-nucleotide polymorphisms (SNPs) (n = 700,022) associated with progression to AIDS 1987 (Cox proportional hazards regression analysis, co-dominant model). Results.  Association with slower progression was observed for SNPs in the gene PARD3B. One of these, rs11884476, reached genome-wide significance (relative hazard = 0.3; P =3. 370 × 10−9) after statistical correction for 700,022 SNPs and contributes 4.52% of the overall variance in AIDS progression in this study. Nine of the top-ranked SNPs define a PARD3B haplotype that also displays significant association with progression to AIDS (hazard ratio, 0.3; P = 3.220 × 10−8). One of these SNPs, rs10185378, is a predicted exonic splicing enhancer; significant alteration in the expression profile of PARD3B splicing transcripts was observed in B cell lines with alternate rs10185378 genotypes. This SNP was typed in European cohorts of rapid progressors and was found to be protective for AIDS 1993 definition (odds ratio, 0.43, P = .025). Conclusions. These observations suggest a potential unsuspected pathway of host genetic influence on the dynamics of AIDS progression. PMID:21502085

Genome-wide investigation and transcriptome analysis of the WRKY gene family in Gossypium.

Science.gov (United States)

Ding, Mingquan; Chen, Jiadong; Jiang, Yurong; Lin, Lifeng; Cao, YueFen; Wang, Minhua; Zhang, Yuting; Rong, Junkang; Ye, Wuwei

2015-02-01

WRKY transcription factors play important roles in various stress responses in diverse plant species. In cotton, this family has not been well studied, especially in relation to fiber development. Here, the genomes and transcriptomes of Gossypium raimondii and Gossypium arboreum were investigated to identify fiber development related WRKY genes. This represents the first comprehensive comparative study of WRKY transcription factors in both diploid A and D cotton species. In total, 112 G. raimondii and 109 G. arboreum WRKY genes were identified. No significant gene structure or domain alterations were detected between the two species, but many SNPs distributed unequally in exon and intron regions. Physical mapping revealed that the WRKY genes in G. arboreum were not located in the corresponding chromosomes of G. raimondii, suggesting great chromosome rearrangement in the diploid cotton genomes. The cotton WRKY genes, especially subgroups I and II, have expanded through multiple whole genome duplications and tandem duplications compared with other plant species. Sequence comparison showed many functionally divergent sites between WRKY subgroups, while the genes within each group are under strong purifying selection. Transcriptome analysis suggested that many WRKY genes participate in specific fiber development processes such as fiber initiation, elongation and maturation with different expression patterns between species. Complex WRKY gene expression such as differential Dt and At allelic gene expression in G. hirsutum and alternative splicing events were also observed in both diploid and tetraploid cottons during fiber development process. In conclusion, this study provides important information on the evolution and function of WRKY gene family in cotton species.

Genome-wide patterns of copy number variation in the diversified chicken genomes using next-generation sequencing.

Science.gov (United States)

Yi, Guoqiang; Qu, Lujiang; Liu, Jianfeng; Yan, Yiyuan; Xu, Guiyun; Yang, Ning

2014-11-07

Copy number variation (CNV) is important and widespread in the genome, and is a major cause of disease and phenotypic diversity. Herein, we performed a genome-wide CNV analysis in 12 diversified chicken genomes based on whole genome sequencing. A total of 8,840 CNV regions (CNVRs) covering 98.2 Mb and representing 9.4% of the chicken genome were identified, ranging in size from 1.1 to 268.8 kb with an average of 11.1 kb. Sequencing-based predictions were confirmed at a high validation rate by two independent approaches, including array comparative genomic hybridization (aCGH) and quantitative PCR (qPCR). The Pearson's correlation coefficients between sequencing and aCGH results ranged from 0.435 to 0.755, and qPCR experiments revealed a positive validation rate of 91.71% and a false negative rate of 22.43%. In total, 2,214 (25.0%) predicted CNVRs span 2,216 (36.4%) RefSeq genes associated with specific biological functions. Besides two previously reported copy number variable genes EDN3 and PRLR, we also found some promising genes with potential in phenotypic variation. Two genes, FZD6 and LIMS1, related to disease susceptibility/resistance are covered by CNVRs. The highly duplicated SOCS2 may lead to higher bone mineral density. Entire or partial duplication of some genes like POPDC3 may have great economic importance in poultry breeding. Our results based on extensive genetic diversity provide a more refined chicken CNV map and genome-wide gene copy number estimates, and warrant future CNV association studies for important traits in chickens.

Genome-wide analysis and identification of stress-responsive genes of the NAM-ATAF1,2-CUC2 transcription factor family in apple.

Science.gov (United States)

Su, Hongyan; Zhang, Shizhong; Yuan, Xiaowei; Chen, Changtian; Wang, Xiao-Fei; Hao, Yu-Jin

2013-10-01

NAC (NAM, ATAF1,2, and CUC2) proteins constitute one of the largest families of plant-specific transcription factors. To date, little is known about the NAC genes in the apple (Malus domestica). In this study, a total of 180 NAC genes were identified in the apple genome and were phylogenetically clustered into six groups (I-VI) with the NAC genes from Arabidopsis and rice. The predicted apple NAC genes were distributed across all of 17 chromosomes at various densities. Additionally, the gene structure and motif compositions of the apple NAC genes were analyzed. Moreover, the expression of 29 selected apple NAC genes was analyzed in different tissues and under different abiotic stress conditions. All of the selected genes, with the exception of four genes, were expressed in at least one of the tissues tested, which indicates that the NAC genes are involved in various aspects of the physiological and developmental processes of the apple. Encouragingly, 17 of the selected genes were found to respond to one or more of the abiotic stress treatments, and these 17 genes included not only the expected 7 genes that were clustered with the well-known stress-related marker genes in group IV but also 10 genes located in other subgroups, none of which contains members that have been reported to be stress-related. To the best of our knowledge, this report describes the first genome-wide analysis of the apple NAC gene family, and the results should provide valuable information for understanding the classification and putative functions of this family. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Genome-wide scans for delineation of candidate genes regulating seed-protein content in chickpea

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Hari Deo eUpadhyaya

2016-03-01

Full Text Available Identification of potential genes/alleles governing complex seed-protein content (SPC trait is essential in marker-assisted breeding for quality trait improvement of chickpea. Henceforth, the present study utilized an integrated genomics-assisted breeding strategy encompassing trait association analysis, selective genotyping in traditional bi-parental mapping population and differential expression profiling for the first-time to understand the complex genetic architecture of quantitative SPC trait in chickpea. For GWAS (genome-wide association study, high-throughput genotyping information of 16376 genome-based SNPs (single nucleotide polymorphism discovered from a structured population of 336 sequenced desi and kabuli accessions [with 150-200 kb LD (linkage disequilibrium decay] was utilized. This led to identification of seven most effective genomic loci (genes associated [10 to 20% with 41% combined PVE (phenotypic variation explained] with SPC trait in chickpea. Regardless of the diverse desi and kabuli genetic backgrounds, a comparable level of association potential of the identified seven genomic loci with SPC trait was observed. Five SPC-associated genes were validated successfully in parental accessions and homozygous individuals of an intra-specific desi RIL (recombinant inbred line mapping population (ICC 12299 x ICC 4958 by selective genotyping. The seed-specific expression, including differential up-regulation (> 4-fold of six SPC-associated genes particularly in accessions, parents and homozygous individuals of the aforementioned mapping population with high level of contrasting seed-protein content (21-22% was evident. Collectively, the integrated genomic approach delineated diverse naturally occurring novel functional SNP allelic variants in six potential candidate genes regulating SPC trait in chickpea. Of these, a non-synonymous SNP allele-carrying zinc finger transcription factor gene exhibiting strong association with SPC trait

Reconstructing transcriptional regulatory networks through genomics data

OpenAIRE

Sun, Ning; Zhao, Hongyu

2009-01-01

One central problem in biology is to understand how gene expression is regulated under different conditions. Microarray gene expression data and other high throughput data have made it possible to dissect transcriptional regulatory networks at the genomics level. Owing to the very large number of genes that need to be studied, the relatively small number of data sets available, the noise in the data and the different natures of the distinct data types, network inference presents great challen...

Whole genome duplications and expansion of the vertebrate GATA transcription factor gene family

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Bowerman Bruce

2009-08-01

Full Text Available Abstract Background GATA transcription factors influence many developmental processes, including the specification of embryonic germ layers. The GATA gene family has significantly expanded in many animal lineages: whereas diverse cnidarians have only one GATA transcription factor, six GATA genes have been identified in many vertebrates, five in many insects, and eleven to thirteen in Caenorhabditis nematodes. All bilaterian animal genomes have at least one member each of two classes, GATA123 and GATA456. Results We have identified one GATA123 gene and one GATA456 gene from the genomic sequence of two invertebrate deuterostomes, a cephalochordate (Branchiostoma floridae and a hemichordate (Saccoglossus kowalevskii. We also have confirmed the presence of six GATA genes in all vertebrate genomes, as well as additional GATA genes in teleost fish. Analyses of conserved sequence motifs and of changes to the exon-intron structure, and molecular phylogenetic analyses of these deuterostome GATA genes support their origin from two ancestral deuterostome genes, one GATA 123 and one GATA456. Comparison of the conserved genomic organization across vertebrates identified eighteen paralogous gene families linked to multiple vertebrate GATA genes (GATA paralogons, providing the strongest evidence yet for expansion of vertebrate GATA gene families via genome duplication events. Conclusion From our analysis, we infer the evolutionary birth order and relationships among vertebrate GATA transcription factors, and define their expansion via multiple rounds of whole genome duplication events. As the genomes of four independent invertebrate deuterostome lineages contain single copy GATA123 and GATA456 genes, we infer that the 0R (pre-genome duplication invertebrate deuterostome ancestor also had two GATA genes, one of each class. Synteny analyses identify duplications of paralogous chromosomal regions (paralogons, from single ancestral vertebrate GATA123 and GATA456

Genome-wide association study of clinical dimensions of schizophrenia

DEFF Research Database (Denmark)

Fanous, Ayman H; Zhou, Baiyu; Aggen, Steven H

2012-01-01

Multiple sources of evidence suggest that genetic factors influence variation in clinical features of schizophrenia. The authors present the first genome-wide association study (GWAS) of dimensional symptom scores among individuals with schizophrenia.......Multiple sources of evidence suggest that genetic factors influence variation in clinical features of schizophrenia. The authors present the first genome-wide association study (GWAS) of dimensional symptom scores among individuals with schizophrenia....

REVIEW: Genome-wide findings in schizophrenia and the role of gene-environment interplay.

Science.gov (United States)

Van Winkel, Ruud; Esquivel, Gabriel; Kenis, Gunter; Wichers, Marieke; Collip, Dina; Peerbooms, Odette; Rutten, Bart; Myin-Germeys, Inez; Van Os, Jim

2010-10-01

The recent advent of genome-wide mass-marker technology has resulted in renewed optimism to unravel the genetic architecture of psychotic disorders. Genome-wide association studies have identified a number of common polymorphisms robustly associated with schizophrenia, in ZNF804A, transcription factor 4, major histocompatibility complex, and neurogranin. In addition, copy number variants (CNVs) in 1q21.1, 2p16.3, 15q11.2, 15q13.3, 16p11.2, and 22q11.2 were convincingly implicated in schizophrenia risk. Furthermore, these studies have suggested considerable genetic overlap with bipolar disorder (particularly for common polymorphisms) and neurodevelopmental disorders such as autism (particularly for CNVs). The influence of these risk variants on relevant intermediate phenotypes needs further study. In addition, there is a need for etiological models of psychosis integrating genetic risk with environmental factors associated with the disorder, focusing specifically on environmental impact on gene expression (epigenetics) and convergence of genes and environment on common biological pathways bringing about larger effects than those of genes or environment in isolation (gene-environment interaction). Collaborative efforts that bring together expertise in statistics, genetics, epidemiology, experimental psychiatry, brain imaging, and clinical psychiatry will be required to succeed in this challenging task. © 2010 Blackwell Publishing Ltd.

Genome-wide analysis of the SBP-box gene family in Chinese cabbage (Brassica rapa subsp. pekinensis).

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Tan, Hua-Wei; Song, Xiao-Ming; Duan, Wei-Ke; Wang, Yan; Hou, Xi-Lin

2015-11-01

The SQUAMOSA PROMOTER BINDING PROTEIN (SBP)-box gene family contains highly conserved plant-specific transcription factors that play an important role in plant development, especially in flowering. Chinese cabbage (Brassica rapa subsp. pekinensis) is a leafy vegetable grown worldwide and is used as a model crop for research in genome duplication. The present study aimed to characterize the SBP-box transcription factor genes in Chinese cabbage. Twenty-nine SBP-box genes were identified in the Chinese cabbage genome and classified into six groups. We identified 23 orthologous and 5 co-orthologous SBP-box gene pairs between Chinese cabbage and Arabidopsis. An interaction network among these genes was constructed. Sixteen SBP-box genes were expressed more abundantly in flowers than in other tissues, suggesting their involvement in flowering. We show that the MiR156/157 family members may regulate the coding regions or 3'-UTR regions of Chinese cabbage SBP-box genes. As SBP-box genes were found to potentially participate in some plant development pathways, quantitative real-time PCR analysis was performed and showed that Chinese cabbage SBP-box genes were also sensitive to the exogenous hormones methyl jasmonic acid and salicylic acid. The SBP-box genes have undergone gene duplication and loss, evolving a more refined regulation for diverse stimulation in plant tissues. Our comprehensive genome-wide analysis provides insights into the SBP-box gene family of Chinese cabbage.

GWIS: Genome-Wide Inferred Statistics for Functions of Multiple Phenotypes

NARCIS (Netherlands)

Nieuwboer, H.A.; Pool, R.; Dolan, C.V.; Boomsma, D.I.; Nivard, M.G.

2016-01-01

Here we present a method of genome-wide inferred study (GWIS) that provides an approximation of genome-wide association study (GWAS) summary statistics for a variable that is a function of phenotypes for which GWAS summary statistics, phenotypic means, and covariances are available. A GWIS can be

Genome-wide identification and function analyses of heat shock transcription factors in potato

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Ruimin eTang

2016-04-01

Full Text Available Heat shock transcription factors (Hsfs play vital roles in the regulation of tolerance to various stresses in living organisms. To dissect the mechanisms of the Hsfs in potato adaptation to abiotic stresses, genome and transcriptome analyses of Hsf gene family were investigated in Solanum tuberosum L. Twenty-seven StHsf members were identified by bioinformatics and phylogenetic analyses and were classified into A, B and C groups according to their structural and phylogenetic features. StHsfs in the same class shared similar gene structures and conserved motifs. The chromosomal location analysis showed that 27 Hsfs were located in 10 of 12 chromosomes (except chromosome 1 and chromosome 5 and that 18 of these genes formed 9 paralogous pairs. Expression profiles of StHsfs in 12 different organs and tissues uncovered distinct spatial expression patterns of these genes and their potential roles in the process of growth and development. Promoter and quantitative real-time polymerase chain reaction (qRT-PCR detections of StHsfs were conducted and demonstrated that these genes were all responsive to various stresses. StHsf004, StHsf007, StHsf009, StHsf014 and StHsf019 were constitutively expressed under non-stress conditions, and some specific Hsfs became the predominant Hsfs in response to different abiotic stresses, indicating their important and diverse regulatory roles in adverse conditions. A co-expression network between StHsfs and StHsf-co-expressed genes was generated based on the publicly-available potato transcriptomic databases and identified key candidate StHsfs for further functional studies.

Evidence for site-specific occupancy of the mitochondrial genome by nuclear transcription factors.

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Georgi K Marinov

Full Text Available Mitochondria contain their own circular genome, with mitochondria-specific transcription and replication systems and corresponding regulatory proteins. All of these proteins are encoded in the nuclear genome and are post-translationally imported into mitochondria. In addition, several nuclear transcription factors have been reported to act in mitochondria, but there has been no comprehensive mapping of their occupancy patterns and it is not clear how many other factors may also be found in mitochondria. Here we address these questions by using ChIP-seq data from the ENCODE, mouseENCODE and modENCODE consortia for 151 human, 31 mouse and 35 C. elegans factors. We identified 8 human and 3 mouse transcription factors with strong localized enrichment over the mitochondrial genome that was usually associated with the corresponding recognition sequence motif. Notably, these sites of occupancy are often the sites with highest ChIP-seq signal intensity within both the nuclear and mitochondrial genomes and are thus best explained as true binding events to mitochondrial DNA, which exist in high copy number in each cell. We corroborated these findings by immunocytochemical staining evidence for mitochondrial localization. However, we were unable to find clear evidence for mitochondrial binding in ENCODE and other publicly available ChIP-seq data for most factors previously reported to localize there. As the first global analysis of nuclear transcription factors binding in mitochondria, this work opens the door to future studies that probe the functional significance of the phenomenon.

Genomic context drives transcription of insertion sequences in the bacterial endosymbiont Wolbachia wVulC.

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Cerveau, Nicolas; Gilbert, Clément; Liu, Chao; Garrett, Roger A; Grève, Pierre; Bouchon, Didier; Cordaux, Richard

2015-06-10

Transposable elements (TEs) are DNA pieces that are present in almost all the living world at variable genomic density. Due to their mobility and density, TEs are involved in a large array of genomic modifications. In eukaryotes, TE expression has been studied in detail in several species. In prokaryotes, studies of IS expression are generally linked to particular copies that induce a modification of neighboring gene expression. Here we investigated global patterns of IS transcription in the Alphaproteobacterial endosymbiont Wolbachia wVulC, using both RT-PCR and bioinformatic analyses. We detected several transcriptional promoters in all IS groups. Nevertheless, only one of the potentially functional IS groups possesses a promoter located upstream of the transposase gene, that could lead up to the production of a functional protein. We found that the majority of IS groups are expressed whatever their functional status. RT-PCR analyses indicate that the transcription of two IS groups lacking internal promoters upstream of the transposase start codon may be driven by the genomic environment. We confirmed this observation with the transcription analysis of individual copies of one IS group. These results suggest that the genomic environment is important for IS expression and it could explain, at least partly, copy number variability of the various IS groups present in the wVulC genome and, more generally, in bacterial genomes. Copyright © 2015 Elsevier B.V. All rights reserved.

Genome-Wide Analysis of Host Responses to Four Different Types of Microorganisms in Bombyx Mori (Lepidoptera: Bombycidae).

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Cheng, Tingcai; Lin, Ping; Huang, Lulin; Wu, Yuqian; Jin, Shengkai; Liu, Chun; Xia, Qingyou

2016-01-01

Several pathogenic microorganisms have been used to investigate the genome-wide transcriptional responses of Bombyx mori to infection. However, studies have so far each focused on one microorganism, and systematic genome-wide comparison of transcriptional responses to different pathogenic microorganisms has not been undertaken. Here, we surveyed transcriptional responses of B. mori to its natural bacterial, viral, and fungal pathogens, Bacillus bombyseptieus, B. mori nucleopolyhedrovirus (BmNPV), and Beauveria bassiana, respectively, and to nonpathogenic Escherichia coli, by microarray analysis. In total, the expression of 2,436, 1,804, 1,743, and 912 B. mori genes was modulated by infection with B. bombyseptieus, BmNPV, B. bassiana, and E. coli, respectively. Notably, the expression of 620, 400, 177, or 165 of these genes was only modulated by infection with B. bombyseptieus, BmNPV, B. bassiana, or E. coli, respectively. In contrast to the expression of genes related to juvenile hormone synthesis and metabolism, that of genes encoding juvenile hormone binding proteins was microorganism-specific. Three basal metabolic pathways were modulated by infection with any of the four microorganisms, and 3, 14, 5, and 2 metabolic pathways were specifically modulated by infection with B. bombyseptieus, BmNPV, B. bassiana, and E. coli, respectively. Interestingly, BmNPV infection modulated the JAK/STAT signaling pathway, whereas both the Imd and Toll signaling pathways were modulated by infection with B. bombyseptieus, B. bassiana, or E. coli These results elucidate potential molecular mechanisms of the host response to different microorganisms, and provide a foundation for further work on host-pathogen interaction. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

A deeper look into transcription regulatory code by preferred pair distance templates for transcription factor binding sites

KAUST Repository

Kulakovskiy, Ivan V.

2011-08-18

Motivation: Modern experimental methods provide substantial information on protein-DNA recognition. Studying arrangements of transcription factor binding sites (TFBSs) of interacting transcription factors (TFs) advances understanding of the transcription regulatory code. Results: We constructed binding motifs for TFs forming a complex with HIF-1α at the erythropoietin 3\\'-enhancer. Corresponding TFBSs were predicted in the segments around transcription start sites (TSSs) of all human genes. Using the genome-wide set of regulatory regions, we observed several strongly preferred distances between hypoxia-responsive element (HRE) and binding sites of a particular cofactor protein. The set of preferred distances was called as a preferred pair distance template (PPDT). PPDT dramatically depended on the TF and orientation of its binding sites relative to HRE. PPDT evaluated from the genome-wide set of regulatory sequences was used to detect significant PPDT-consistent binding site pairs in regulatory regions of hypoxia-responsive genes. We believe PPDT can help to reveal the layout of eukaryotic regulatory segments. © The Author 2011. Published by Oxford University Press. All rights reserved.

On the analysis of genome-wide association studies in family-based designs: a universal, robust analysis approach and an application to four genome-wide association studies.

Directory of Open Access Journals (Sweden)

Sungho Won

2009-11-01

Full Text Available For genome-wide association studies in family-based designs, we propose a new, universally applicable approach. The new test statistic exploits all available information about the association, while, by virtue of its design, it maintains the same robustness against population admixture as traditional family-based approaches that are based exclusively on the within-family information. The approach is suitable for the analysis of almost any trait type, e.g. binary, continuous, time-to-onset, multivariate, etc., and combinations of those. We use simulation studies to verify all theoretically derived properties of the approach, estimate its power, and compare it with other standard approaches. We illustrate the practical implications of the new analysis method by an application to a lung-function phenotype, forced expiratory volume in one second (FEV1 in 4 genome-wide association studies.

Genome-wide analysis of miRNA and mRNA transcriptomes during amelogenesis.

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Yin, Kaifeng; Hacia, Joseph G; Zhong, Zhe; Paine, Michael L

2014-11-19

In the rodent incisor during amelogenesis, as ameloblast cells transition from secretory stage to maturation stage, their morphology and transcriptome profiles change dramatically. Prior whole genome transcriptome analysis has given a broad picture of the molecular activities dominating both stages of amelogenesis, but this type of analysis has not included miRNA transcript profiling. In this study, we set out to document which miRNAs and corresponding target genes change significantly as ameloblasts transition from secretory- to maturation-stage amelogenesis. Total RNA samples from both secretory- and maturation-stage rat enamel organs were subjected to genome-wide miRNA and mRNA transcript profiling. We identified 59 miRNAs that were differentially expressed at the maturation stage relative to the secretory stage of enamel development (False Discovery Rate (FDR)<0.05, fold change (FC)≥1.8). In parallel, transcriptome profiling experiments identified 1,729 mRNA transcripts that were differentially expressed in the maturation stage compared to the secretory stage (FDR<0.05, FC≥1.8). Based on bioinformatics analyses, 5.8% (629 total) of these differentially expressed genes (DEGS) were highlighted as being the potential targets of 59 miRNAs that were differentially expressed in the opposite direction, in the same tissue samples. Although the number of predicted target DEGs was not higher than baseline expectations generated by examination of stably expressed miRNAs, Gene Ontology (GO) analysis showed that these 629 DEGS were enriched for ion transport, pH regulation, calcium handling, endocytotic, and apoptotic activities. Seven differentially expressed miRNAs (miR-21, miR-31, miR-488, miR-153, miR-135b, miR-135a and miR298) in secretory- and/or maturation-stage enamel organs were confirmed by in situ hybridization. Further, we used luciferase reporter assays to provide evidence that two of these differentially expressed miRNAs, miR-153 and miR-31, are potential

Genome-wide Escherichia coli stress response and improved tolerance towards industrially relevant chemicals

DEFF Research Database (Denmark)

Rau, Martin Holm; Calero Valdayo, Patricia; Lennen, Rebecca

2016-01-01

Economically viable biobased production of bulk chemicals and biofuels typically requires high product titers. During microbial bioconversion this often leads to product toxicity, and tolerance is therefore a critical element in the engineering of production strains. Here, a systems biology...... approach was employed to understand the chemical stress response of Escherichia coli, including a genome-wide screen for mutants with increased fitness during chemical stress. Twelve chemicals with significant production potential were selected, consisting of organic solvent-like chemicals (butanol......, hydroxy-γ-butyrolactone, 1,4-butanediol, furfural), organic acids (acetate, itaconic acid, levulinic acid, succinic acid), amino acids (serine, threonine) and membrane-intercalating chemicals (decanoic acid, geraniol). The transcriptional response towards these chemicals revealed large overlaps...

Genome-Wide Association Study (GWAS) and Genome-Wide Environment Interaction Study (GWEIS) of Depressive Symptoms in African American and Hispanic/Latina Women

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Dunn, Erin C.; Wiste, Anna; Radmanesh, Farid; Almli, Lynn M.; Gogarten, Stephanie M.; Sofer, Tamar; Faul, Jessica D.; Kardia, Sharon L.R.; Smith, Jennifer A.; Weir, David R.; Zhao, Wei; Soare, Thomas W.; Mirza, Saira S.; Hek, Karin; Tiemeier, Henning W.; Goveas, Joseph S.; Sarto, Gloria E.; Snively, Beverly M.; Cornelis, Marilyn; Koenen, Karestan C.; Kraft, Peter; Purcell, Shaun; Ressler, Kerry J.; Rosand, Jonathan; Wassertheil-Smoller, Sylvia; Smoller, Jordan W.

2016-01-01

Background Genome-wide association studies (GWAS) have been unable to identify variants linked to depression. We hypothesized that examining depressive symptoms and considering gene-environment interaction (G×E) might improve efficiency for gene discovery. We therefore conducted a GWAS and genome-wide environment interaction study (GWEIS) of depressive symptoms. Methods Using data from the SHARe cohort of the Women’s Health Initiative, comprising African Americans (n=7179) and Hispanics/Latinas (n=3138), we examined genetic main effects and G×E with stressful life events and social support. We also conducted a heritability analysis using genome-wide complex trait analysis (GCTA). Replication was attempted in four independent cohorts. Results No SNPs achieved genome-wide significance for main effects in either discovery sample. The top signals in African Americans were rs73531535 (located 20kb from GPR139, p=5.75×10−8) and rs75407252 (intronic to CACNA2D3, p=6.99×10−7). In Hispanics/Latinas, the top signals were rs2532087 (located 27kb from CD38, p=2.44×10−7) and rs4542757 (intronic to DCC, p=7.31×10−7). In the GWEIS with stressful life events, one interaction signal was genome-wide significant in African Americans (rs4652467; p=4.10×10−10; located 14kb from CEP350). This interaction was not observed in a smaller replication cohort. Although heritability estimates for depressive symptoms and stressful life events were each less than 10%, they were strongly genetically correlated (rG=0.95), suggesting that common variation underlying depressive symptoms and stressful life event exposure, though modest on their own, were highly overlapping in this sample. Conclusions Our results underscore the need for larger samples, more GWEIS, and greater investigation into genetic and environmental determinants of depressive symptoms in minorities. PMID:27038408

Genome-wide analysis of Tol2 transposon reintegration in zebrafish.

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Kondrychyn, Igor; Garcia-Lecea, Marta; Emelyanov, Alexander; Parinov, Sergey; Korzh, Vladimir

2009-09-08

Tol2, a member of the hAT family of transposons, has become a useful tool for genetic manipulation of model animals, but information about its interactions with vertebrate genomes is still limited. Furthermore, published reports on Tol2 have mainly been based on random integration of the transposon system after co-injection of a plasmid DNA harboring the transposon and a transposase mRNA. It is important to understand how Tol2 would behave upon activation after integration into the genome. We performed a large-scale enhancer trap (ET) screen and generated 338 insertions of the Tol2 transposon-based ET cassette into the zebrafish genome. These insertions were generated by remobilizing the transposon from two different donor sites in two transgenic lines. We found that 39% of Tol2 insertions occurred in transcription units, mostly into introns. Analysis of the transposon target sites revealed no strict specificity at the DNA sequence level. However, Tol2 was prone to target AT-rich regions with weak palindromic consensus sequences centered at the insertion site. Our systematic analysis of sequential remobilizations of the Tol2 transposon from two independent sites within a vertebrate genome has revealed properties such as a tendency to integrate into transcription units and into AT-rich palindrome-like sequences. This information will influence the development of various applications involving DNA transposons and Tol2 in particular.

Ebolavirus comparative genomics

DEFF Research Database (Denmark)

Jun, Se-Ran; Leuze, Michael R.; Nookaew, Intawat

2015-01-01

The 2014 Ebola outbreak in West Africa is the largest documented for this virus. To examine the dynamics of this genome, we compare more than 100 currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms...

Genome-Wide Investigation of WRKY Transcription Factors Involved in Terminal Drought Stress Response in Common Bean.

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Wu, Jing; Chen, Jibao; Wang, Lanfen; Wang, Shumin

2017-01-01

WRKY transcription factor plays a key role in drought stress. However, the characteristics of the WRKY gene family in the common bean ( Phaseolus vulgaris L.) are unknown. In this study, we identified 88 complete WRKY proteins from the draft genome sequence of the "G19833" common bean. The predicted genes were non-randomly distributed in all chromosomes. Basic information, amino acid motifs, phylogenetic tree and the expression patterns of PvWRKY genes were analyzed, and the proteins were classified into groups 1, 2, and 3. Group 2 was further divided into five subgroups: 2a, 2b, 2c, 2d, and 2e. Finally, we detected 19 WRKY genes that were responsive to drought stress using qRT-PCR; 11 were down-regulated, and 8 were up-regulated under drought stress. This study comprehensively examines WRKY proteins in the common bean, a model food legume, and it provides a foundation for the functional characterization of the WRKY family and opportunities for understanding the mechanisms of drought stress tolerance in this plant.

ChloroMitoCU: Codon patterns across organelle genomes for functional genomics and evolutionary applications.

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Sablok, Gaurav; Chen, Ting-Wen; Lee, Chi-Ching; Yang, Chi; Gan, Ruei-Chi; Wegrzyn, Jill L; Porta, Nicola L; Nayak, Kinshuk C; Huang, Po-Jung; Varotto, Claudio; Tang, Petrus

2017-06-01

Organelle genomes are widely thought to have arisen from reduction events involving cyanobacterial and archaeal genomes, in the case of chloroplasts, or α-proteobacterial genomes, in the case of mitochondria. Heterogeneity in base composition and codon preference has long been the subject of investigation of topics ranging from phylogenetic distortion to the design of overexpression cassettes for transgenic expression. From the overexpression point of view, it is critical to systematically analyze the codon usage patterns of the organelle genomes. In light of the importance of codon usage patterns in the development of hyper-expression organelle transgenics, we present ChloroMitoCU, the first-ever curated, web-based reference catalog of the codon usage patterns in organelle genomes. ChloroMitoCU contains the pre-compiled codon usage patterns of 328 chloroplast genomes (29,960 CDS) and 3,502 mitochondrial genomes (49,066 CDS), enabling genome-wide exploration and comparative analysis of codon usage patterns across species. ChloroMitoCU allows the phylogenetic comparison of codon usage patterns across organelle genomes, the prediction of codon usage patterns based on user-submitted transcripts or assembled organelle genes, and comparative analysis with the pre-compiled patterns across species of interest. ChloroMitoCU can increase our understanding of the biased patterns of codon usage in organelle genomes across multiple clades. ChloroMitoCU can be accessed at: http://chloromitocu.cgu.edu.tw/. © The Author 2017. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Construction of a genomic library of the human cytomegalovirus genome and analysis of late transcription of its inverted internal repeat region

International Nuclear Information System (INIS)

Silva, K.F.S.T.

1989-01-01

The investigations described in this dissertation were designed to determine the transcriptionally active DNA sequences of IIR region and to identify the viral mRNA transcribed from the transcriptionally most active DNA sequences of that region during late phase of HCMV Towne infection. Preliminary transcriptional studies which included the hybridization of a southern blot of XbaI digested entire HCMV genome to 32 P-labelled late phase infected cell A + RNA, indicated that late viral transcripts homologous to XbaI Q fragment of IIR region were very highly abundant while XbaI Q fragment showed a very low transcriptional activity. To facilitate further analysis of late transcription of IIR region, the entire DNA sequences of IIR region were molecularly cloned as U, S, and H BamHI fragments in pACYC-184 plasmid vector. In addition, to be used in future studies on other regions of the genome, except for y and c' smaller fragments the entire 240 kb HCMV genome was cloned as BamHI fragments in the same vector. Furthermore, the U, S, and H BamHI fragments were mapped with six other restriction enzymes in order to use that mapping data in subsequent transcriptional analysis of the IIR region. Further localization of transcriptionally active DNA sequences within IIR region was achieved by hybridization of southern blots of restricted U, S, and H BamHI fragments with 3' 32 P-labelled infected cell late A + RNA. The 1.5 kb EcooRI subfragments of S BamHI fragment and the adjoining 0.72 kb XhoI subfragment of H BamHI fragment revealed the highest level of transcription, although the remainder of the S fragment was also transcribed at a substantial level. The U fragment and the remainder of the H fragment was transcribed at a very low level

Improved reproducibility in genome-wide DNA methylation analysis for PAXgene® fixed samples compared to restored FFPE DNA

DEFF Research Database (Denmark)

Andersen, Gitte Brinch; Hager, Henrik; Hansen, Lise Lotte

2014-01-01

Chip. Quantitative DNA methylation analysis demonstrated that the methylation profile in PAXgene-fixed tissues showed, in comparison with restored FFPE samples, a higher concordance with the profile detected in frozen samples. We demonstrate, for the first time, that DNA from PAXgene conserved tissue performs better......Formalin fixation has been the standard method for conservation of clinical specimens for decades. However, a major drawback is the high degradation of nucleic acids, which complicates its use in genome-wide analyses. Unbiased identification of biomarkers, however, requires genome-wide studies......, precluding the use of the valuable archives of specimens with long-term follow-up data. Therefore, restoration protocols for DNA from formalin-fixed and paraffin-embedded (FFPE) samples have been developed, although they are cost-intensive and time-consuming. An alternative to FFPE and snap...

Genome-wide comparative analysis of 20 miniature inverted-repeat transposable element families in Brassica rapa and B. oleracea.

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Perumal Sampath

Full Text Available Miniature inverted-repeat transposable elements (MITEs are ubiquitous, non-autonomous class II transposable elements. Here, we conducted genome-wide comparative analysis of 20 MITE families in B. rapa, B. oleracea, and Arabidopsis thaliana. A total of 5894 and 6026 MITE members belonging to the 20 families were found in the whole genome pseudo-chromosome sequences of B. rapa and B. oleracea, respectively. Meanwhile, only four of the 20 families, comprising 573 members, were identified in the Arabidopsis genome, indicating that most of the families were activated in the Brassica genus after divergence from Arabidopsis. Copy numbers varied from 4 to 1459 for each MITE family, and there was up to 6-fold variation between B. rapa and B. oleracea. In particular, analysis of intact members showed that whereas eleven families were present in similar copy numbers in B. rapa and B. oleracea, nine families showed copy number variation ranging from 2- to 16-fold. Four of those families (BraSto-3, BraTo-3, 4, 5 were more abundant in B. rapa, and the other five (BraSto-1, BraSto-4, BraTo-1, 7 and BraHAT-1 were more abundant in B. oleracea. Overall, 54% and 51% of the MITEs resided in or within 2 kb of a gene in the B. rapa and B. oleracea genomes, respectively. Notably, 92 MITEs were found within the CDS of annotated genes, suggesting that MITEs might play roles in diversification of genes in the recently triplicated Brassica genome. MITE insertion polymorphism (MIP analysis of 289 MITE members showed that 52% and 23% were polymorphic at the inter- and intra-species levels, respectively, indicating that there has been recent MITE activity in the Brassica genome. These recently activated MITE families with abundant MIP will provide useful resources for molecular breeding and identification of novel functional genes arising from MITE insertion.

Genome-wide identification of Pseudomonas aeruginosa virulence-related genes using a Caenorhabditis elegans infection model.

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Rhonda L Feinbaum

Full Text Available Pseudomonas aeruginosa strain PA14 is an opportunistic human pathogen capable of infecting a wide range of organisms including the nematode Caenorhabditis elegans. We used a non-redundant transposon mutant library consisting of 5,850 clones corresponding to 75% of the total and approximately 80% of the non-essential PA14 ORFs to carry out a genome-wide screen for attenuation of PA14 virulence in C. elegans. We defined a functionally diverse 180 mutant set (representing 170 unique genes necessary for normal levels of virulence that included both known and novel virulence factors. Seven previously uncharacterized virulence genes (ABC transporters PchH and PchI, aminopeptidase PepP, ATPase/molecular chaperone ClpA, cold shock domain protein PA0456, putative enoyl-CoA hydratase/isomerase PA0745, and putative transcriptional regulator PA14_27700 were characterized with respect to pigment production and motility and all but one of these mutants exhibited pleiotropic defects in addition to their avirulent phenotype. We examined the collection of genes required for normal levels of PA14 virulence with respect to occurrence in P. aeruginosa strain-specific genomic regions, location on putative and known genomic islands, and phylogenetic distribution across prokaryotes. Genes predominantly contributing to virulence in C. elegans showed neither a bias for strain-specific regions of the P. aeruginosa genome nor for putatively horizontally transferred genomic islands. Instead, within the collection of virulence-related PA14 genes, there was an overrepresentation of genes with a broad phylogenetic distribution that also occur with high frequency in many prokaryotic clades, suggesting that in aggregate the genes required for PA14 virulence in C. elegans are biased towards evolutionarily conserved genes.

Genome-wide identification of Pseudomonas aeruginosa virulence-related genes using a Caenorhabditis elegans infection model.

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Feinbaum, Rhonda L; Urbach, Jonathan M; Liberati, Nicole T; Djonovic, Slavica; Adonizio, Allison; Carvunis, Anne-Ruxandra; Ausubel, Frederick M

2012-01-01

Pseudomonas aeruginosa strain PA14 is an opportunistic human pathogen capable of infecting a wide range of organisms including the nematode Caenorhabditis elegans. We used a non-redundant transposon mutant library consisting of 5,850 clones corresponding to 75% of the total and approximately 80% of the non-essential PA14 ORFs to carry out a genome-wide screen for attenuation of PA14 virulence in C. elegans. We defined a functionally diverse 180 mutant set (representing 170 unique genes) necessary for normal levels of virulence that included both known and novel virulence factors. Seven previously uncharacterized virulence genes (ABC transporters PchH and PchI, aminopeptidase PepP, ATPase/molecular chaperone ClpA, cold shock domain protein PA0456, putative enoyl-CoA hydratase/isomerase PA0745, and putative transcriptional regulator PA14_27700) were characterized with respect to pigment production and motility and all but one of these mutants exhibited pleiotropic defects in addition to their avirulent phenotype. We examined the collection of genes required for normal levels of PA14 virulence with respect to occurrence in P. aeruginosa strain-specific genomic regions, location on putative and known genomic islands, and phylogenetic distribution across prokaryotes. Genes predominantly contributing to virulence in C. elegans showed neither a bias for strain-specific regions of the P. aeruginosa genome nor for putatively horizontally transferred genomic islands. Instead, within the collection of virulence-related PA14 genes, there was an overrepresentation of genes with a broad phylogenetic distribution that also occur with high frequency in many prokaryotic clades, suggesting that in aggregate the genes required for PA14 virulence in C. elegans are biased towards evolutionarily conserved genes.

Genome-Wide Identification of Polycomb Target Genes Reveals a Functional Association of Pho with Scm in Bombyx mori

OpenAIRE

Li, Zhiqing; Cheng, Daojun; Mon, Hiroaki; Tatsuke, Tsuneyuki; Zhu, Li; Xu, Jian; Lee, Jae Man; Xia, Qingyou; Kusakabe, Takahiro

2012-01-01

Polycomb group (PcG) proteins are evolutionarily conserved chromatin modifiers and act together in three multimeric complexes, Polycomb repressive complex 1 (PRC1), Polycomb repressive complex 2 (PRC2), and Pleiohomeotic repressive complex (PhoRC), to repress transcription of the target genes. Here, we identified Polycomb target genes in Bombyx mori with holocentric centromere using genome-wide expression screening based on the knockdown of BmSCE, BmESC, BmPHO, or BmSCM gene, which represent ...

Transcription-associated mutational pressure in the Parvovirus B19 genome: Reactivated genomes contribute to the variability of viral populations.

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Khrustalev, Vladislav Victorovich; Ermalovich, Marina Anatolyevna; Hübschen, Judith M; Khrustaleva, Tatyana Aleksandrovna

2017-12-21

In this study we used non-overlapping parts of the two long open reading frames coding for nonstructural (NS) and capsid (VP) proteins of all available sequences of the Parvovirus B19 subgenotype 1a genome and found out that the rates of A to G, C to T and A to T mutations are higher in the first long reading frame (NS) of the virus than in the second one (VP). This difference in mutational pressure directions for two parts of the same viral genome can be explained by the fact of transcription of just the first long reading frame during the lifelong latency in nonerythroid cells. Adenine deamination (producing A to G and A to T mutations) and cytosine deamination (producing C to T mutations) occur more frequently in transcriptional bubbles formed by DNA "plus" strand of the first open reading frame. These mutations can be inherited only in case of reactivation of the infectious virus due to the help of Adenovirus that allows latent Parvovirus B19 to start transcription of the second reading frame and then to replicate its genome by the rolling circle mechanism using the specific origin. Results of this study provide evidence that the genomes reactivated from latency make significant contributions to the variability of Parvovirus B19. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Genome-Wide Breast Cancer Scan in African Americans

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2010-06-01

SNPs from the African American breast cancer scan to COGs , a European collaborative study which is has designed a SNP array with that will be genotyped...Award Number: W81XWH-08-1-0383 TITLE: A Genome-wide Breast Cancer Scan in African Americans PRINCIPAL INVESTIGATOR: Christopher A...SUBTITLE A Genome-wide Breast Cancer Scan in African Americans 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-08-1-0383 5c. PROGRAM

Genome-wide binding and transcriptome analysis of human farnesoid X receptor in primary human hepatocytes.

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Le Zhan

Full Text Available Farnesoid X receptor (FXR, NR1H4 is a ligand-activated transcription factor, belonging to the nuclear receptor superfamily. FXR is highly expressed in the liver and is essential in regulating bile acid homeostasis. FXR deficiency is implicated in numerous liver diseases and mice with modulation of FXR have been used as animal models to study liver physiology and pathology. We have reported genome-wide binding of FXR in mice by chromatin immunoprecipitation - deep sequencing (ChIP-seq, with results indicating that FXR may be involved in regulating diverse pathways in liver. However, limited information exists for the functions of human FXR and the suitability of using murine models to study human FXR functions.In the current study, we performed ChIP-seq in primary human hepatocytes (PHHs treated with a synthetic FXR agonist, GW4064 or DMSO control. In parallel, RNA deep sequencing (RNA-seq and RNA microarray were performed for GW4064 or control treated PHHs and wild type mouse livers, respectively.ChIP-seq showed similar profiles of genome-wide FXR binding in humans and mice in terms of motif analysis and pathway prediction. However, RNA-seq and microarray showed more different transcriptome profiles between PHHs and mouse livers upon GW4064 treatment.In summary, we have established genome-wide human FXR binding and transcriptome profiles. These results will aid in determining the human FXR functions, as well as judging to what level the mouse models could be used to study human FXR functions.

Genome Wide Identification of Orthologous ZIP Genes Associated with Zinc and Iron Translocation in Setaria italica

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Ganesh Alagarasan

2017-05-01

Full Text Available Genes in the ZIP family encode transcripts to store and transport bivalent metal micronutrient, particularly iron (Fe and or zinc (Zn. These transcripts are important for a variety of functions involved in the developmental and physiological processes in many plant species, including most, if not all, Poaceae plant species and the model species Arabidopsis. Here, we present the report of a genome wide investigation of orthologous ZIP genes in Setaria italica and the identification of 7 single copy genes. RT-PCR shows 4 of them could be used to increase the bio-availability of zinc and iron content in grains. Of 36 ZIP members, 25 genes have traces of signal peptide based sub-cellular localization, as compared to those of plant species studied previously, yet translocation of ions remains unclear. In silico analysis of gene structure and protein nature suggests that these two were preeminent in shaping the functional diversity of the ZIP gene family in S. italica. NAC, bZIP and bHLH are the predominant Fe and Zn responsive transcription factors present in SiZIP genes. Together, our results provide new insights into the signal peptide based/independent iron and zinc translocation in the plant system and allowed identification of ZIP genes that may be involved in the zinc and iron absorption from the soil, and thus transporting it to the cereal grain underlying high micronutrient accumulation.

Genome-wide decoding of hierarchical modular structure of transcriptional regulation by cis-element and expression clustering.

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Leyfer, Dmitriy; Weng, Zhiping

2005-09-01

A holistic approach to the study of cellular processes is identifying both gene-expression changes and regulatory elements promoting such changes. Cellular regulatory processes can be viewed as transcriptional modules (TMs), groups of coexpressed genes regulated by groups of transcription factors (TFs). We set out to devise a method that would identify TMs while avoiding arbitrary thresholds on TM sizes and number. Assuming that gene expression is determined by TFs that bind to the gene's promoter, clustering of genes based on TF binding sites (cis-elements) should create gene groups similar to those obtained by gene expression clustering. Intersections between the expression and cis-element-based gene clusters reveal TMs. Statistical significance assigned to each TM allows identification of regulatory units of any size. Our method correctly identifies the number and sizes of TMs on simulated datasets. We demonstrate that yeast experimental TMs are biologically relevant by comparing them with MIPS and GO categories. Our modules are in statistically significant agreement with TMs from other research groups. This work suggests that there is no preferential division of biological processes into regulatory units; each degree of partitioning exhibits a slice of biological network revealing hierarchical modular organization of transcriptional regulation.

Novel applications of array comparative genomic hybridization in molecular diagnostics.

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Cheung, Sau W; Bi, Weimin

2018-05-31

In 2004, the implementation of array comparative genomic hybridization (array comparative genome hybridization [CGH]) into clinical practice marked a new milestone for genetic diagnosis. Array CGH and single-nucleotide polymorphism (SNP) arrays enable genome-wide detection of copy number changes in a high resolution, and therefore microarray has been recognized as the first-tier test for patients with intellectual disability or multiple congenital anomalies, and has also been applied prenatally for detection of clinically relevant copy number variations in the fetus. Area covered: In this review, the authors summarize the evolution of array CGH technology from their diagnostic laboratory, highlighting exonic SNP arrays developed in the past decade which detect small intragenic copy number changes as well as large DNA segments for the region of heterozygosity. The applications of array CGH to human diseases with different modes of inheritance with the emphasis on autosomal recessive disorders are discussed. Expert commentary: An exonic array is a powerful and most efficient clinical tool in detecting genome wide small copy number variants in both dominant and recessive disorders. However, whole-genome sequencing may become the single integrated platform for detection of copy number changes, single-nucleotide changes as well as balanced chromosomal rearrangements in the near future.

Genome-wide association studies and resting heart rate

DEFF Research Database (Denmark)

Oskari Kilpeläinen, Tuomas

2016-01-01

Genome-wide association studies (GWASs) have revolutionized the search for genetic variants regulating resting heart rate. In the last 10 years, GWASs have led to the identification of at least 21 novel heart rate loci. These discoveries have provided valuable insights into the mechanisms...... and pathways that regulate heart rate and link heart rate to cardiovascular morbidity and mortality. GWASs capture majority of genetic variation in a population sample by utilizing high-throughput genotyping chips measuring genotypes for up to several millions of SNPs across the genome in thousands...... of individuals. This allows the identification of the strongest heart rate associated signals at genome-wide level. While GWASs provide robust statistical evidence of the association of a given genetic locus with heart rate, they are only the starting point for detailed follow-up studies to locate the causal...

Genome-wide comparative analysis of ABC systems in the Bdellovibrio-and-like organisms.

Science.gov (United States)

Li, Nan; Chen, Huan; Williams, Henry N

2015-05-10

Bdellovibrio-and-like organisms (BALOs) are gram-negative, predatory bacteria with wide variations in genome sizes and GC content and ecological habitats. The ATP-binding cassette (ABC) systems have been identified in several prokaryotes, fungi and plants and have a role in transport of materials in and out of cells and in cellular processes. However, knowledge of the ABC systems of BALOs remains obscure. A total of 269 putative ABC proteins were identified in BALOs. The genes encoding these ABC systems occupy nearly 1.3% of the gene content in freshwater Bdellovibrio strains and about 0.7% in their saltwater counterparts. The proteins found belong to 25 ABC system families based on their structural characteristics and functions. Among these, 16 families function as importers, 6 as exporters and 3 are involved in various cellular processes. Eight of these 25 ABC system families were deduced to be the core set of ABC systems conserved in all BALOs. All Bacteriovorax strains have 28 or less ABC systems. On the contrary, the freshwater Bdellovibrio strains have more ABC systems, typically around 51. In the genome of Bdellovibrio exovorus JSS (CP003537.1), 53 putative ABC systems were detected, representing the highest number among all the BALO genomes examined in this study. Unexpected high numbers of ABC systems involved in cellular processes were found in all BALOs. Phylogenetic analysis suggests that the majority of ABC proteins can be assigned into many separate families with high bootstrap supports (>50%). In this study, a general framework of sequence-structure-function connections for the ABC systems in BALOs was revealed providing novel insights for future investigations. Copyright © 2015 Elsevier B.V. All rights reserved.

Genome-wide analysis of protein-protein interactions and involvement of viral proteins in SARS-CoV replication.

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Ji'an Pan

Full Text Available Analyses of viral protein-protein interactions are an important step to understand viral protein functions and their underlying molecular mechanisms. In this study, we adopted a mammalian two-hybrid system to screen the genome-wide intraviral protein-protein interactions of SARS coronavirus (SARS-CoV and therefrom revealed a number of novel interactions which could be partly confirmed by in vitro biochemical assays. Three pairs of the interactions identified were detected in both directions: non-structural protein (nsp 10 and nsp14, nsp10 and nsp16, and nsp7 and nsp8. The interactions between the multifunctional nsp10 and nsp14 or nsp16, which are the unique proteins found in the members of Nidovirales with large RNA genomes including coronaviruses and toroviruses, may have important implication for the mechanisms of replication/transcription complex assembly and functions of these viruses. Using a SARS-CoV replicon expressing a luciferase reporter under the control of a transcription regulating sequence, it has been shown that several viral proteins (N, X and SUD domains of nsp3, and nsp12 provided in trans stimulated the replicon reporter activity, indicating that these proteins may regulate coronavirus replication and transcription. Collectively, our findings provide a basis and platform for further characterization of the functions and mechanisms of coronavirus proteins.

Genome-wide characterization of the WRKY gene family in radish (Raphanus sativus L.) reveals its critical functions under different abiotic stresses.

Science.gov (United States)

Karanja, Bernard Kinuthia; Fan, Lianxue; Xu, Liang; Wang, Yan; Zhu, Xianwen; Tang, Mingjia; Wang, Ronghua; Zhang, Fei; Muleke, Everlyne M'mbone; Liu, Liwang

2017-11-01

The radish WRKY gene family was genome-widely identified and played critical roles in response to multiple abiotic stresses. The WRKY is among the largest transcription factors (TFs) associated with multiple biological activities for plant survival, including control response mechanisms against abiotic stresses such as heat, salinity, and heavy metals. Radish is an important root vegetable crop and therefore characterization and expression pattern investigation of WRKY transcription factors in radish is imperative. In the present study, 126 putative WRKY genes were retrieved from radish genome database. Protein sequence and annotation scrutiny confirmed that RsWRKY proteins possessed highly conserved domains and zinc finger motif. Based on phylogenetic analysis results, RsWRKYs candidate genes were divided into three groups (Group I, II and III) with the number 31, 74, and 20, respectively. Additionally, gene structure analysis revealed that intron-exon patterns of the WRKY genes are highly conserved in radish. Linkage map analysis indicated that RsWRKY genes were distributed with varying densities over nine linkage groups. Further, RT-qPCR analysis illustrated the significant variation of 36 RsWRKY genes under one or more abiotic stress treatments, implicating that they might be stress-responsive genes. In total, 126 WRKY TFs were identified from the R. sativus genome wherein, 35 of them showed abiotic stress-induced expression patterns. These results provide a genome-wide characterization of RsWRKY TFs and baseline for further functional dissection and molecular evolution investigation, specifically for improving abiotic stress resistances with an ultimate goal of increasing yield and quality of radish.

Adiponectin Concentrations: A Genome-wide Association Study

Science.gov (United States)

Jee, Sun Ha; Sull, Jae Woong; Lee, Jong-Eun; Shin, Chol; Park, Jongkeun; Kimm, Heejin; Cho, Eun-Young; Shin, Eun-Soon; Yun, Ji Eun; Park, Ji Wan; Kim, Sang Yeun; Lee, Sun Ju; Jee, Eun Jung; Baik, Inkyung; Kao, Linda; Yoon, Sungjoo Kim; Jang, Yangsoo; Beaty, Terri H.

2010-01-01

Adiponectin is associated with obesity and insulin resistance. To date, there has been no genome-wide association study (GWAS) of adiponectin levels in Asians. Here we present a GWAS of a cohort of Korean volunteers. A total of 4,001 subjects were genotyped by using a genome-wide marker panel in a two-stage design (979 subjects initially and 3,022 in a second stage). Another 2,304 subjects were used for follow-up replication studies with selected markers. In the discovery phase, the top SNP associated with mean log adiponectin was rs3865188 in CDH13 on chromosome 16 (p = 1.69 × 10−15 in the initial sample, p = 6.58 × 10−39 in the second genome-wide sample, and p = 2.12 × 10−32 in the replication sample). The meta-analysis p value for rs3865188 in all 6,305 individuals was 2.82 × 10−83. The association of rs3865188 with high-molecular-weight adiponectin (p = 7.36 × 10−58) was even stronger in the third sample. A reporter assay that evaluated the effects of a CDH13 promoter SNP in complete linkage disequilibrium with rs3865188 revealed that the major allele increased expression 2.2-fold. This study clearly shows that genetic variants in CDH13 influence adiponectin levels in Korean adults. PMID:20887962

LASSIM-A network inference toolbox for genome-wide mechanistic modeling.

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Rasmus Magnusson

2017-06-01

with truly systems-level data. We demonstrate the power of this approach by inferring a mechanistically motivated, genome-wide model of the Th2 transcription regulatory system, which plays an important role in several immune related diseases.

Comparative genomics of vesicomyid clam (Bivalvia: Mollusca chemosynthetic symbionts

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Girguis Peter R

2008-12-01

Full Text Available Abstract Background The Vesicomyidae (Bivalvia: Mollusca are a family of clams that form symbioses with chemosynthetic gamma-proteobacteria. They exist in environments such as hydrothermal vents and cold seeps and have a reduced gut and feeding groove, indicating a large dependence on their endosymbionts for nutrition. Recently, two vesicomyid symbiont genomes were sequenced, illuminating the possible nutritional contributions of the symbiont to the host and making genome-wide evolutionary analyses possible. Results To examine the genomic evolution of the vesicomyid symbionts, a comparative genomics framework, including the existing genomic data combined with heterologous microarray hybridization results, was used to analyze conserved gene content in four vesicomyid symbiont genomes. These four symbionts were chosen to include a broad phylogenetic sampling of the vesicomyid symbionts and represent distinct chemosynthetic environments: cold seeps and hydrothermal vents. Conclusion The results of this comparative genomics analysis emphasize the importance of the symbionts' chemoautotrophic metabolism within their hosts. The fact that these symbionts appear to be metabolically capable autotrophs underscores the extent to which the host depends on them for nutrition and reveals the key to invertebrate colonization of these challenging environments.

Genome-wide identification and characterization of the bHLH gene family in tomato.

Science.gov (United States)

Sun, Hua; Fan, Hua-Jie; Ling, Hong-Qing

2015-01-22

The basic helix-loop-helix (bHLH) proteins are a large superfamily of transcription factors, and play a central role in a wide range of metabolic, physiological, and developmental processes in higher organisms. Tomato is an important vegetable crop, and its genome sequence has been published recently. However, the bHLH gene family of tomato has not been systematically identified and characterized yet. In this study, we identified 159 bHLH protein-encoding genes (SlbHLH) in tomato genome and analyzed their structures. Although bHLH domains were conserved among the bHLH proteins between tomato and Arabidopsis, the intron sequences and distribution of tomato bHLH genes were extremely different compared with Arabidopsis. The gene duplication analysis showed that 58.5% and 6.3% of SlbHLH genes belonged to low-stringency and high-stringency duplication, respectively, indicating that the SlbHLH genes are mainly generated via short low-stringency region duplication in tomato. Subsequently, we classified the SlbHLH genes into 21 subfamilies by phylogenetic tree analysis, and predicted their possible functions by comparison with their homologous genes of Arabidopsis. Moreover, the expression profile analysis of SlbHLH genes from 10 different tissues showed that 21 SlbHLH genes exhibited tissue-specific expression. Further, we identified that 11 SlbHLH genes were associated with fruit development and ripening (eight of them associated with young fruit development and three with fruit ripening). The evolutionary analysis revealed that 92% SlbHLH genes might be evolved from ancestor(s) originated from early land plant, and 8% from algae. In this work, we systematically identified SlbHLHs by analyzing the tomato genome sequence using a set of bioinformatics approaches, and characterized their chromosomal distribution, gene structures, duplication, phylogenetic relationship and expression profiles, as well predicted their possible biological functions via comparative analysis

Comparative Genome Viewer

International Nuclear Information System (INIS)

Molineris, I.; Sales, G.

2009-01-01

The amount of information about genomes, both in the form of complete sequences and annotations, has been exponentially increasing in the last few years. As a result there is the need for tools providing a graphical representation of such information that should be comprehensive and intuitive. Visual representation is especially important in the comparative genomics field since it should provide a combined view of data belonging to different genomes. We believe that existing tools are limited in this respect as they focus on a single genome at a time (conservation histograms) or compress alignment representation to a single dimension. We have therefore developed a web-based tool called Comparative Genome Viewer (Cgv): it integrates a bidimensional representation of alignments between two regions, both at small and big scales, with the richness of annotations present in other genome browsers. We give access to our system through a web-based interface that provides the user with an interactive representation that can be updated in real time using the mouse to move from region to region and to zoom in on interesting details.

Simultaneous genome-wide inference of physical, genetic, regulatory, and functional pathway components.

Directory of Open Access Journals (Sweden)

Christopher Y Park

2010-11-01

Full Text Available Biomolecular pathways are built from diverse types of pairwise interactions, ranging from physical protein-protein interactions and modifications to indirect regulatory relationships. One goal of systems biology is to bridge three aspects of this complexity: the growing body of high-throughput data assaying these interactions; the specific interactions in which individual genes participate; and the genome-wide patterns of interactions in a system of interest. Here, we describe methodology for simultaneously predicting specific types of biomolecular interactions using high-throughput genomic data. This results in a comprehensive compendium of whole-genome networks for yeast, derived from ∼3,500 experimental conditions and describing 30 interaction types, which range from general (e.g. physical or regulatory to specific (e.g. phosphorylation or transcriptional regulation. We used these networks to investigate molecular pathways in carbon metabolism and cellular transport, proposing a novel connection between glycogen breakdown and glucose utilization supported by recent publications. Additionally, 14 specific predicted interactions in DNA topological change and protein biosynthesis were experimentally validated. We analyzed the systems-level network features within all interactomes, verifying the presence of small-world properties and enrichment for recurring network motifs. This compendium of physical, synthetic, regulatory, and functional interaction networks has been made publicly available through an interactive web interface for investigators to utilize in future research at http://function.princeton.edu/bioweaver/.

easyGWAS: A Cloud-Based Platform for Comparing the Results of Genome-Wide Association Studies.

Science.gov (United States)

Grimm, Dominik G; Roqueiro, Damian; Salomé, Patrice A; Kleeberger, Stefan; Greshake, Bastian; Zhu, Wangsheng; Liu, Chang; Lippert, Christoph; Stegle, Oliver; Schölkopf, Bernhard; Weigel, Detlef; Borgwardt, Karsten M

2017-01-01

The ever-growing availability of high-quality genotypes for a multitude of species has enabled researchers to explore the underlying genetic architecture of complex phenotypes at an unprecedented level of detail using genome-wide association studies (GWAS). The systematic comparison of results obtained from GWAS of different traits opens up new possibilities, including the analysis of pleiotropic effects. Other advantages that result from the integration of multiple GWAS are the ability to replicate GWAS signals and to increase statistical power to detect such signals through meta-analyses. In order to facilitate the simple comparison of GWAS results, we present easyGWAS, a powerful, species-independent online resource for computing, storing, sharing, annotating, and comparing GWAS. The easyGWAS tool supports multiple species, the uploading of private genotype data and summary statistics of existing GWAS, as well as advanced methods for comparing GWAS results across different experiments and data sets in an interactive and user-friendly interface. easyGWAS is also a public data repository for GWAS data and summary statistics and already includes published data and results from several major GWAS. We demonstrate the potential of easyGWAS with a case study of the model organism Arabidopsis thaliana , using flowering and growth-related traits. © 2016 American Society of Plant Biologists. All rights reserved.

Modeling Ebola Virus Genome Replication and Transcription with Minigenome Systems.

Science.gov (United States)

Cressey, Tessa; Brauburger, Kristina; Mühlberger, Elke

2017-01-01

In this chapter, we describe the minigenome system for Ebola virus (EBOV), which reconstitutes EBOV polymerase activity in cells and can be used to model viral genome replication and transcription. This protocol comprises all steps including cell culture, plasmid preparation, transfection, and luciferase reporter assay readout.

Genome-wide identification and comparative analysis of conserved and novel microRNAs in grafted watermelon by high-throughput sequencing.

Science.gov (United States)

Liu, Na; Yang, Jinghua; Guo, Shaogui; Xu, Yong; Zhang, Mingfang

2013-01-01

MicroRNAs (miRNAs) are a class of endogenous small non-coding RNAs involved in the post-transcriptional gene regulation and play a critical role in plant growth, development and stresses response. However less is known about miRNAs involvement in grafting behaviors, especially with the watermelon (Citrullus lanatus L.) crop, which is one of the most important agricultural crops worldwide. Grafting method is commonly used in watermelon production in attempts to improve its adaptation to abiotic and biotic stresses, in particular to the soil-borne fusarium wilt disease. In this study, Solexa sequencing has been used to discover small RNA populations and compare miRNAs on genome-wide scale in watermelon grafting system. A total of 11,458,476, 11,614,094 and 9,339,089 raw reads representing 2,957,751, 2,880,328 and 2,964,990 unique sequences were obtained from the scions of self-grafted watermelon and watermelon grafted on-to bottle gourd and squash at two true-leaf stage, respectively. 39 known miRNAs belonging to 30 miRNA families and 80 novel miRNAs were identified in our small RNA dataset. Compared with self-grafted watermelon, 20 (5 known miRNA families and 15 novel miRNAs) and 47 (17 known miRNA families and 30 novel miRNAs) miRNAs were expressed significantly different in watermelon grafted on to bottle gourd and squash, respectively. MiRNAs expressed differentially when watermelon was grafted onto different rootstocks, suggesting that miRNAs might play an important role in diverse biological and metabolic processes in watermelon and grafting may possibly by changing miRNAs expressions to regulate plant growth and development as well as adaptation to stresses. The small RNA transcriptomes obtained in this study provided insights into molecular aspects of miRNA-mediated regulation in grafted watermelon. Obviously, this result would provide a basis for further unravelling the mechanism on how miRNAs information is exchanged between scion and rootstock in grafted

Rewiring the severe acute respiratory syndrome coronavirus (SARS-CoV) transcription circuit: Engineering a recombination-resistant genome

Science.gov (United States)

Yount, Boyd; Roberts, Rhonda S.; Lindesmith, Lisa; Baric, Ralph S.

2006-08-01

Live virus vaccines provide significant protection against many detrimental human and animal diseases, but reversion to virulence by mutation and recombination has reduced appeal. Using severe acute respiratory syndrome coronavirus as a model, we engineered a different transcription regulatory circuit and isolated recombinant viruses. The transcription network allowed for efficient expression of the viral transcripts and proteins, and the recombinant viruses replicated to WT levels. Recombinant genomes were then constructed that contained mixtures of the WT and mutant regulatory circuits, reflecting recombinant viruses that might occur in nature. Although viable viruses could readily be isolated from WT and recombinant genomes containing homogeneous transcription circuits, chimeras that contained mixed regulatory networks were invariantly lethal, because viable chimeric viruses were not isolated. Mechanistically, mixed regulatory circuits promoted inefficient subgenomic transcription from inappropriate start sites, resulting in truncated ORFs and effectively minimize viral structural protein expression. Engineering regulatory transcription circuits of intercommunicating alleles successfully introduces genetic traps into a viral genome that are lethal in RNA recombinant progeny viruses. regulation | systems biology | vaccine design

Comprehensive meta-analysis of Signal Transducers and Activators of Transcription (STAT genomic binding patterns discerns cell-specific cis-regulatory modules

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Kang Keunsoo

2013-01-01

Full Text Available Abstract Background Cytokine-activated transcription factors from the STAT (Signal Transducers and Activators of Transcription family control common and context-specific genetic programs. It is not clear to what extent cell-specific features determine the binding capacity of seven STAT members and to what degree they share genetic targets. Molecular insight into the biology of STATs was gained from a meta-analysis of 29 available ChIP-seq data sets covering genome-wide occupancy of STATs 1, 3, 4, 5A, 5B and 6 in several cell types. Results We determined that the genomic binding capacity of STATs is primarily defined by the cell type and to a lesser extent by individual family members. For example, the overlap of shared binding sites between STATs 3 and 5 in T cells is greater than that between STAT5 in T cells and non-T cells. Even for the top 1,000 highly enriched STAT binding sites, ~15% of STAT5 binding sites in mouse female liver are shared by other STATs in different cell types while in T cells ~90% of STAT5 binding sites are co-occupied by STAT3, STAT4 and STAT6. In addition, we identified 116 cis-regulatory modules (CRM, which are recognized by all STAT members across cell types defining a common JAK-STAT signature. Lastly, in liver STAT5 binding significantly coincides with binding of the cell-specific transcription factors HNF4A, FOXA1 and FOXA2 and is associated with cell-type specific gene transcription. Conclusions Our results suggest that genomic binding of STATs is primarily determined by the cell type and further specificity is achieved in part by juxtaposed binding of cell-specific transcription factors.

Uncovering transcriptional regulation of glycerol metabolism in Aspergilli through genome-wide gene expression data anlysis

DEFF Research Database (Denmark)

Salazar, Margarita Pena; Vongsangnak, Wanwipa; Panagiotou, Gianni

2009-01-01

Glycerol is catabolized by a wide range of microorganisms including Aspergillus species. To identify the transcriptional regulation of glycerol metabolism in Aspergillus, we analyzed data from triplicate batch fermentations of three different Aspergilli (Aspergillus nidulans, Aspergillus oryzae...... and Aspergillus niger) with glucose and glycerol as carbon sources. Protein comparisons and cross-analysis with gene expression data of all three species resulted in the identification of 88 genes having a conserved response across the three Aspergilli. A promoter analysis of the up-regulated genes led...... to the identification of a conserved binding site for a putative regulator to be 5′-TGCGGGGA-3′, a binding site that is similar to the binding site for Adr1 in yeast and humans. We show that this Adr1 consensus binding sequence was over-represented on promoter regions of several genes in A. nidulans, A. oryzae and A...

Genome-wide analysis of Tol2 transposon reintegration in zebrafish

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Parinov Sergey

2009-09-01

Full Text Available Abstract Background Tol2, a member of the hAT family of transposons, has become a useful tool for genetic manipulation of model animals, but information about its interactions with vertebrate genomes is still limited. Furthermore, published reports on Tol2 have mainly been based on random integration of the transposon system after co-injection of a plasmid DNA harboring the transposon and a transposase mRNA. It is important to understand how Tol2 would behave upon activation after integration into the genome. Results We performed a large-scale enhancer trap (ET screen and generated 338 insertions of the Tol2 transposon-based ET cassette into the zebrafish genome. These insertions were generated by remobilizing the transposon from two different donor sites in two transgenic lines. We found that 39% of Tol2 insertions occurred in transcription units, mostly into introns. Analysis of the transposon target sites revealed no strict specificity at the DNA sequence level. However, Tol2 was prone to target AT-rich regions with weak palindromic consensus sequences centered at the insertion site. Conclusion Our systematic analysis of sequential remobilizations of the Tol2 transposon from two independent sites within a vertebrate genome has revealed properties such as a tendency to integrate into transcription units and into AT-rich palindrome-like sequences. This information will influence the development of various applications involving DNA transposons and Tol2 in particular.

Genome-wide profiling of DNA-binding proteins using barcode-based multiplex Solexa sequencing.

Science.gov (United States)

Raghav, Sunil Kumar; Deplancke, Bart

2012-01-01

Chromatin immunoprecipitation (ChIP) is a commonly used technique to detect the in vivo binding of proteins to DNA. ChIP is now routinely paired to microarray analysis (ChIP-chip) or next-generation sequencing (ChIP-Seq) to profile the DNA occupancy of proteins of interest on a genome-wide level. Because ChIP-chip introduces several biases, most notably due to the use of a fixed number of probes, ChIP-Seq has quickly become the method of choice as, depending on the sequencing depth, it is more sensitive, quantitative, and provides a greater binding site location resolution. With the ever increasing number of reads that can be generated per sequencing run, it has now become possible to analyze several samples simultaneously while maintaining sufficient sequence coverage, thus significantly reducing the cost per ChIP-Seq experiment. In this chapter, we provide a step-by-step guide on how to perform multiplexed ChIP-Seq analyses. As a proof-of-concept, we focus on the genome-wide profiling of RNA Polymerase II as measuring its DNA occupancy at different stages of any biological process can provide insights into the gene regulatory mechanisms involved. However, the protocol can also be used to perform multiplexed ChIP-Seq analyses of other DNA-binding proteins such as chromatin modifiers and transcription factors.

Genomic consequences of selection and genome-wide association mapping in soybean.

Science.gov (United States)

Wen, Zixiang; Boyse, John F; Song, Qijian; Cregan, Perry B; Wang, Dechun

2015-09-03

Crop improvement always involves selection of specific alleles at genes controlling traits of agronomic importance, likely resulting in detectable signatures of selection within the genome of modern soybean (Glycine max L. Merr.). The identification of these signatures of selection is meaningful from the perspective of evolutionary biology and for uncovering the genetic architecture of agronomic traits. To this end, two populations of soybean, consisting of 342 landraces and 1062 improved lines, were genotyped with the SoySNP50K Illumina BeadChip containing 52,041 single nucleotide polymorphisms (SNPs), and systematically phenotyped for 9 agronomic traits. A cross-population composite likelihood ratio (XP-CLR) method was used to screen the signals of selective sweeps. A total of 125 candidate selection regions were identified, many of which harbored genes potentially involved in crop improvement. To further investigate whether these candidate regions were in fact enriched for genes affected by selection, genome-wide association studies (GWAS) were conducted on 7 selection traits targeted in soybean breeding (grain yield, plant height, lodging, maturity date, seed coat color, seed protein and oil content) and 2 non-selection traits (pubescence and flower color). Major genomic regions associated with selection traits overlapped with candidate selection regions, whereas no overlap of this kind occurred for the non-selection traits, suggesting that the selection sweeps identified are associated with traits of agronomic importance. Multiple novel loci and refined map locations of known loci related to these traits were also identified. These findings illustrate that comparative genomic analyses, especially when combined with GWAS, are a promising approach to dissect the genetic architecture of complex traits.

Genome-wide analysis of regions similar to promoters of histone genes

KAUST Repository

Chowdhary, Rajesh; Bajic, Vladimir B.; Dong, Difeng; Wong, Limsoon; Liu, Jun S

2010-01-01

of histone and histone-coregulated gene transcription initiation. While these hypotheses still remain to be verified, we believe that these form a useful resource for researchers to further explore regulation of human histone genes and human genome

Meta-analysis of genome-wide association from genomic prediction models

Science.gov (United States)

A limitation of many genome-wide association studies (GWA) in animal breeding is that there are many loci with small effect sizes; thus, larger sample sizes (N) are required to guarantee suitable power of detection. To increase sample size, results from different GWA can be combined in a meta-analys...

GenHtr: a tool for comparative assessment of genetic heterogeneity in microbial genomes generated by massive short-read sequencing

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Yu GongXin

2010-10-01

Full Text Available Abstract Background Microevolution is the study of short-term changes of alleles within a population and their effects on the phenotype of organisms. The result of the below-species-level evolution is heterogeneity, where populations consist of subpopulations with a large number of structural variations. Heterogeneity analysis is thus essential to our understanding of how selective and neutral forces shape bacterial populations over a short period of time. The Solexa Genome Analyzer, a next-generation sequencing platform, allows millions of short sequencing reads to be obtained with great accuracy, allowing for the ability to study the dynamics of the bacterial population at the whole genome level. The tool referred to as GenHtr was developed for genome-wide heterogeneity analysis. Results For particular bacterial strains, GenHtr relies on a set of Solexa short reads on given bacteria pathogens and their isogenic reference genome to identify heterogeneity sites, the chromosomal positions with multiple variants of genes in the bacterial population, and variations that occur in large gene families. GenHtr accomplishes this by building and comparatively analyzing genome-wide heterogeneity genotypes for both the newly sequenced genomes (using massive short-read sequencing and their isogenic reference (using simulated data. As proof of the concept, this approach was applied to SRX007711, the Solexa sequencing data for a newly sequenced Staphylococcus aureus subsp. USA300 cell line, and demonstrated that it could predict such multiple variants. They include multiple variants of genes critical in pathogenesis, e.g. genes encoding a LysR family transcriptional regulator, 23 S ribosomal RNA, and DNA mismatch repair protein MutS. The heterogeneity results in non-synonymous and nonsense mutations, leading to truncated proteins for both LysR and MutS. Conclusion GenHtr was developed for genome-wide heterogeneity analysis. Although it is much more time

A universal genomic coordinate translator for comparative genomics.

Science.gov (United States)

Zamani, Neda; Sundström, Görel; Meadows, Jennifer R S; Höppner, Marc P; Dainat, Jacques; Lantz, Henrik; Haas, Brian J; Grabherr, Manfred G

2014-06-30

Genomic duplications constitute major events in the evolution of species, allowing paralogous copies of genes to take on fine-tuned biological roles. Unambiguously identifying the orthology relationship between copies across multiple genomes can be resolved by synteny, i.e. the conserved order of genomic sequences. However, a comprehensive analysis of duplication events and their contributions to evolution would require all-to-all genome alignments, which increases at N2 with the number of available genomes, N. Here, we introduce Kraken, software that omits the all-to-all requirement by recursively traversing a graph of pairwise alignments and dynamically re-computing orthology. Kraken scales linearly with the number of targeted genomes, N, which allows for including large numbers of genomes in analyses. We first evaluated the method on the set of 12 Drosophila genomes, finding that orthologous correspondence computed indirectly through a graph of multiple synteny maps comes at minimal cost in terms of sensitivity, but reduces overall computational runtime by an order of magnitude. We then used the method on three well-annotated mammalian genomes, human, mouse, and rat, and show that up to 93% of protein coding transcripts have unambiguous pairwise orthologous relationships across the genomes. On a nucleotide level, 70 to 83% of exons match exactly at both splice junctions, and up to 97% on at least one junction. We last applied Kraken to an RNA-sequencing dataset from multiple vertebrates and diverse tissues, where we confirmed that brain-specific gene family members, i.e. one-to-many or many-to-many homologs, are more highly correlated across species than single-copy (i.e. one-to-one homologous) genes. Not limited to protein coding genes, Kraken also identifies thousands of newly identified transcribed loci, likely non-coding RNAs that are consistently transcribed in human, chimpanzee and gorilla, and maintain significant correlation of expression levels across

Revisiting the classification of curtoviruses based on genome-wide pairwise identity

KAUST Repository

Varsani, Arvind; Martin, Darren Patrick; Navas-Castillo, Jesú s; Moriones, Enrique; Herná ndez-Zepeda, Cecilia; Idris, Ali; Murilo Zerbini, F.; Brown, Judith K.

2014-01-01

Members of the genus Curtovirus (family Geminiviridae) are important pathogens of many wild and cultivated plant species. Until recently, relatively few full curtovirus genomes have been characterised. However, with the 19 full genome sequences now available in public databases, we revisit the proposed curtovirus species and strain classification criteria. Using pairwise identities coupled with phylogenetic evidence, revised species and strain demarcation guidelines have been instituted. Specifically, we have established 77% genome-wide pairwise identity as a species demarcation threshold and 94% genome-wide pairwise identity as a strain demarcation threshold. Hence, whereas curtovirus sequences with >77% genome-wide pairwise identity would be classified as belonging to the same species, those sharing >94% identity would be classified as belonging to the same strain. We provide step-by-step guidelines to facilitate the classification of newly discovered curtovirus full genome sequences and a set of defined criteria for naming new species and strains. The revision yields three curtovirus species: Beet curly top virus (BCTV), Spinach severe surly top virus (SpSCTV) and Horseradish curly top virus (HrCTV). © 2014 Springer-Verlag Wien.

Revisiting the classification of curtoviruses based on genome-wide pairwise identity

KAUST Repository

Varsani, Arvind

2014-01-25

Members of the genus Curtovirus (family Geminiviridae) are important pathogens of many wild and cultivated plant species. Until recently, relatively few full curtovirus genomes have been characterised. However, with the 19 full genome sequences now available in public databases, we revisit the proposed curtovirus species and strain classification criteria. Using pairwise identities coupled with phylogenetic evidence, revised species and strain demarcation guidelines have been instituted. Specifically, we have established 77% genome-wide pairwise identity as a species demarcation threshold and 94% genome-wide pairwise identity as a strain demarcation threshold. Hence, whereas curtovirus sequences with >77% genome-wide pairwise identity would be classified as belonging to the same species, those sharing >94% identity would be classified as belonging to the same strain. We provide step-by-step guidelines to facilitate the classification of newly discovered curtovirus full genome sequences and a set of defined criteria for naming new species and strains. The revision yields three curtovirus species: Beet curly top virus (BCTV), Spinach severe surly top virus (SpSCTV) and Horseradish curly top virus (HrCTV). © 2014 Springer-Verlag Wien.

Genome-wide identification of coding and non-coding conserved sequence tags in human and mouse genomes

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Maggi Giorgio P

2008-06-01

Full Text Available Abstract Background The accurate detection of genes and the identification of functional regions is still an open issue in the annotation of genomic sequences. This problem affects new genomes but also those of very well studied organisms such as human and mouse where, despite the great efforts, the inventory of genes and regulatory regions is far from complete. Comparative genomics is an effective approach to address this problem. Unfortunately it is limited by the computational requirements needed to perform genome-wide comparisons and by the problem of discriminating between conserved coding and non-coding sequences. This discrimination is often based (thus dependent on the availability of annotated proteins. Results In this paper we present the results of a comprehensive comparison of human and mouse genomes performed with a new high throughput grid-based system which allows the rapid detection of conserved sequences and accurate assessment of their coding potential. By detecting clusters of coding conserved sequences the system is also suitable to accurately identify potential gene loci. Following this analysis we created a collection of human-mouse conserved sequence tags and carefully compared our results to reliable annotations in order to benchmark the reliability of our classifications. Strikingly we were able to detect several potential gene loci supported by EST sequences but not corresponding to as yet annotated genes. Conclusion Here we present a new system which allows comprehensive comparison of genomes to detect conserved coding and non-coding sequences and the identification of potential gene loci. Our system does not require the availability of any annotated sequence thus is suitable for the analysis of new or poorly annotated genomes.

Genome-wide Anaplasma phagocytophilum AnkA-DNA interactions are enriched in intergenic regions and gene promoters and correlate with infection-induced differential gene expression.

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J Stephen Dumler

2016-09-01

Full Text Available Anaplasma phagocytophilum, an obligate intracellular prokaryote, infects neutrophils and alters cardinal functions via reprogrammed transcription. Large contiguous regions of neutrophil chromosomes are differentially expressed during infection. Secreted A. phagocytophilum effector AnkA transits into the neutrophil or granulocyte nucleus to complex with DNA in heterochromatin across all chromosomes. AnkA binds to gene promoters to dampen cis-transcription and also has features of matrix attachment region (MAR-binding proteins that regulate three-dimensional chromatin architecture and coordinate transcriptional programs encoded in topologically-associated chromatin domains. We hypothesize that identification of additional AnkA binding sites will better delineate how A. phagocytophilum infection results in reprogramming of the neutrophil genome. Using AnkA-binding ChIP-seq, we showed that AnkA binds broadly throughout all chromosomes in a reproducible pattern, especially at: i intergenic regions predicted to be matrix attachment regions (MARs; ii within predicted lamina-associated domains; and iii at promoters ≤3,000 bp upstream of transcriptional start sites. These findings provide genome-wide support for AnkA as a regulator of cis-gene transcription. Moreover, the dominant mark of AnkA in distal intergenic regions known to be AT-enriched, coupled with frequent enrichment in the nuclear lamina, provides strong support for its role as a MAR-binding protein and genome re-organizer. AnkA must be considered a prime candidate to promote neutrophil reprogramming and subsequent functional changes that belie improved microbial fitness and pathogenicity.

a potential source of spurious associations in genome-wide ...

Indian Academy of Sciences (India)

2010-04-01

Apr 1, 2010 ... Genome-wide association studies (GWAS) examine the entire human genome with the goal of identifying genetic variants. (usually single nucleotide polymorphisms (SNPs)) that are associated with phenotypic traits such as disease status and drug response. The discordance of significantly associated ...

Genome-wide association study of smoking initiation and current smoking

DEFF Research Database (Denmark)

Vink, Jacqueline M; Smit, August B; de Geus, Eco J C

2009-01-01

For the identification of genes associated with smoking initiation and current smoking, genome-wide association analyses were carried out in 3497 subjects. Significant genes that replicated in three independent samples (n = 405, 5810, and 1648) were visualized into a biologically meaningful network......) and cell-adhesion molecules (e.g., CDH23). We conclude that a network-based genome-wide association approach can identify genes influencing smoking behavior....

Revised genomic structure of the human ghrelin gene and identification of novel exons, alternative splice variants and natural antisense transcripts

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Herington Adrian C

2007-08-01

Full Text Available Abstract Background Ghrelin is a multifunctional peptide hormone expressed in a range of normal tissues and pathologies. It has been reported that the human ghrelin gene consists of five exons which span 5 kb of genomic DNA on chromosome 3 and includes a 20 bp non-coding first exon (20 bp exon 0. The availability of bioinformatic tools enabling comparative analysis and the finalisation of the human genome prompted us to re-examine the genomic structure of the ghrelin locus. Results We have demonstrated the presence of an additional novel exon (exon -1 and 5' extensions to exon 0 and 1 using comparative in silico analysis and have demonstrated their existence experimentally using RT-PCR and 5' RACE. A revised exon-intron structure demonstrates that the human ghrelin gene spans 7.2 kb and consists of six rather than five exons. Several ghrelin gene-derived splice forms were detected in a range of human tissues and cell lines. We have demonstrated ghrelin gene-derived mRNA transcripts that do not code for ghrelin, but instead may encode the C-terminal region of full-length preproghrelin (C-ghrelin, which contains the coding region for obestatin and a transcript encoding obestatin-only. Splice variants that differed in their 5' untranslated regions were also found, suggesting a role of these regions in the post-transcriptional regulation of preproghrelin translation. Finally, several natural antisense transcripts, termed ghrelinOS (ghrelin opposite strand transcripts, were demonstrated via orientation-specific RT-PCR, 5' RACE and in silico analysis of ESTs and cloned amplicons. Conclusion The sense and antisense alternative transcripts demonstrated in this study may function as non-coding regulatory RNA, or code for novel protein isoforms. This is the first demonstration of putative obestatin and C-ghrelin specific transcripts and these findings suggest that these ghrelin gene-derived peptides may also be produced independently of preproghrelin

Comparative genomics reveals insights into avian genome evolution and adaptation

DEFF Research Database (Denmark)

Zhang, Guojie; Li, Cai; Li, Qiye

2014-01-01

Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, ...

A genome-wide association study of aging.

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Walter, Stefan; Atzmon, Gil; Demerath, Ellen W; Garcia, Melissa E; Kaplan, Robert C; Kumari, Meena; Lunetta, Kathryn L; Milaneschi, Yuri; Tanaka, Toshiko; Tranah, Gregory J; Völker, Uwe; Yu, Lei; Arnold, Alice; Benjamin, Emelia J; Biffar, Reiner; Buchman, Aron S; Boerwinkle, Eric; Couper, David; De Jager, Philip L; Evans, Denis A; Harris, Tamara B; Hoffmann, Wolfgang; Hofman, Albert; Karasik, David; Kiel, Douglas P; Kocher, Thomas; Kuningas, Maris; Launer, Lenore J; Lohman, Kurt K; Lutsey, Pamela L; Mackenbach, Johan; Marciante, Kristin; Psaty, Bruce M; Reiman, Eric M; Rotter, Jerome I; Seshadri, Sudha; Shardell, Michelle D; Smith, Albert V; van Duijn, Cornelia; Walston, Jeremy; Zillikens, M Carola; Bandinelli, Stefania; Baumeister, Sebastian E; Bennett, David A; Ferrucci, Luigi; Gudnason, Vilmundur; Kivimaki, Mika; Liu, Yongmei; Murabito, Joanne M; Newman, Anne B; Tiemeier, Henning; Franceschini, Nora

2011-11-01

Human longevity and healthy aging show moderate heritability (20%-50%). We conducted a meta-analysis of genome-wide association studies from 9 studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium for 2 outcomes: (1) all-cause mortality, and (2) survival free of major disease or death. No single nucleotide polymorphism (SNP) was a genome-wide significant predictor of either outcome (p < 5 × 10(-8)). We found 14 independent SNPs that predicted risk of death, and 8 SNPs that predicted event-free survival (p < 10(-5)). These SNPs are in or near genes that are highly expressed in the brain (HECW2, HIP1, BIN2, GRIA1), genes involved in neural development and function (KCNQ4, LMO4, GRIA1, NETO1) and autophagy (ATG4C), and genes that are associated with risk of various diseases including cancer and Alzheimer's disease. In addition to considerable overlap between the traits, pathway and network analysis corroborated these findings. These findings indicate that variation in genes involved in neurological processes may be an important factor in regulating aging free of major disease and achieving longevity. Copyright © 2011 Elsevier Inc. All rights reserved.

Gigwa-Genotype investigator for genome-wide analyses.

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Sempéré, Guilhem; Philippe, Florian; Dereeper, Alexis; Ruiz, Manuel; Sarah, Gautier; Larmande, Pierre

2016-06-06

Exploring the structure of genomes and analyzing their evolution is essential to understanding the ecological adaptation of organisms. However, with the large amounts of data being produced by next-generation sequencing, computational challenges arise in terms of storage, search, sharing, analysis and visualization. This is particularly true with regards to studies of genomic variation, which are currently lacking scalable and user-friendly data exploration solutions. Here we present Gigwa, a web-based tool that provides an easy and intuitive way to explore large amounts of genotyping data by filtering it not only on the basis of variant features, including functional annotations, but also on genotype patterns. The data storage relies on MongoDB, which offers good scalability properties. Gigwa can handle multiple databases and may be deployed in either single- or multi-user mode. In addition, it provides a wide range of popular export formats. The Gigwa application is suitable for managing large amounts of genomic variation data. Its user-friendly web interface makes such processing widely accessible. It can either be simply deployed on a workstation or be used to provide a shared data portal for a given community of researchers.

Genome-Wide Association Identifies Multiple Genomic Regions Associated with Susceptibility to and Control of Ovine Lentivirus

Science.gov (United States)

2012-10-17

to varying degrees of dyspnea (respiratory distress), cachexia (body condition wasting), mastitis , arthritis, and/or encephalitis [5,6]. One of the...General Transcription Factor IIH, polypeptide 5), the gene order does not agree with other mammal genomes including cow , human, dog, and mouse, and it may

Genome-wide association yields new sequence variants at seven loci that associate with measures of obesity

DEFF Research Database (Denmark)

Thorleifsson, Gudmar; Walters, G Bragi; Gudbjartsson, Daniel F

2009-01-01

Obesity results from the interaction of genetic and environmental factors. To search for sequence variants that affect variation in two common measures of obesity, weight and body mass index (BMI), both of which are highly heritable, we performed a genome-wide association (GWA) study with 305......,846 SNPs typed in 25,344 Icelandic, 2,998 Dutch, 1,890 European Americans and 1,160 African American subjects and combined the results with previously published results from the Diabetes Genetics Initiative (DGI) on 3,024 Scandinavians. We selected 43 variants in 19 regions for follow-up in 5,586 Danish...... individuals and compared the results to a genome-wide study on obesity-related traits from the GIANT consortium. In total, 29 variants, some correlated, in 11 chromosomal regions reached a genome-wide significance threshold of P

Genome-wide comparison of paired fresh frozen and formalin-fixed paraffin-embedded gliomas by custom BAC and oligonucleotide array comparative genomic hybridization: facilitating analysis of archival gliomas.

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Mohapatra, Gayatry; Engler, David A; Starbuck, Kristen D; Kim, James C; Bernay, Derek C; Scangas, George A; Rousseau, Audrey; Batchelor, Tracy T; Betensky, Rebecca A; Louis, David N

2011-04-01

Array comparative genomic hybridization (aCGH) is a powerful tool for detecting DNA copy number alterations (CNA). Because diffuse malignant gliomas are often sampled by small biopsies, formalin-fixed paraffin-embedded (FFPE) blocks are often the only tissue available for genetic analysis; FFPE tissues are also needed to study the intratumoral heterogeneity that characterizes these neoplasms. In this paper, we present a combination of evaluations and technical advances that provide strong support for the ready use of oligonucleotide aCGH on FFPE diffuse gliomas. We first compared aCGH using bacterial artificial chromosome (BAC) arrays in 45 paired frozen and FFPE gliomas, and demonstrate a high concordance rate between FFPE and frozen DNA in an individual clone-level analysis of sensitivity and specificity, assuring that under certain array conditions, frozen and FFPE DNA can perform nearly identically. However, because oligonucleotide arrays offer advantages to BAC arrays in genomic coverage and practical availability, we next developed a method of labeling DNA from FFPE tissue that allows efficient hybridization to oligonucleotide arrays. To demonstrate utility in FFPE tissues, we applied this approach to biphasic anaplastic oligoastrocytomas and demonstrate CNA differences between DNA obtained from the two components. Therefore, BAC and oligonucleotide aCGH can be sensitive and specific tools for detecting CNAs in FFPE DNA, and novel labeling techniques enable the routine use of oligonucleotide arrays for FFPE DNA. In combination, these advances should facilitate genome-wide analysis of rare, small and/or histologically heterogeneous gliomas from FFPE tissues.

Insights into the Pathogenesis of Anaplastic Large-Cell Lymphoma through Genome-wide DNA Methylation Profiling

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Melanie R. Hassler

2016-10-01

Full Text Available Aberrant DNA methylation patterns in malignant cells allow insight into tumor evolution and development and can be used for disease classification. Here, we describe the genome-wide DNA methylation signatures of NPM-ALK-positive (ALK+ and NPM-ALK-negative (ALK− anaplastic large-cell lymphoma (ALCL. We find that ALK+ and ALK− ALCL share common DNA methylation changes for genes involved in T cell differentiation and immune response, including TCR and CTLA-4, without an ALK-specific impact on tumor DNA methylation in gene promoters. Furthermore, we uncover a close relationship between global ALCL DNA methylation patterns and those in distinct thymic developmental stages and observe tumor-specific DNA hypomethylation in regulatory regions that are enriched for conserved transcription factor binding motifs such as AP1. Our results indicate similarity between ALCL tumor cells and thymic T cell subsets and a direct relationship between ALCL oncogenic signaling and DNA methylation through transcription factor induction and occupancy.

Sequencing and Comparative Analysis of the Straw Mushroom (Volvariella volvacea) Genome

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Bao, Dapeng; Gong, Ming; Zheng, Huajun; Chen, Mingjie; Zhang, Liang; Wang, Hong; Jiang, Jianping; Wu, Lin; Zhu, Yongqiang; Zhu, Gang; Zhou, Yan; Li, Chuanhua; Wang, Shengyue; Zhao, Yan; Zhao, Guoping; Tan, Qi

2013-01-01

Volvariella volvacea, the edible straw mushroom, is a highly nutritious food source that is widely cultivated on a commercial scale in many parts of Asia using agricultural wastes (rice straw, cotton wastes) as growth substrates. However, developments in V. volvacea cultivation have been limited due to a low biological efficiency (i.e. conversion of growth substrate to mushroom fruit bodies), sensitivity to low temperatures, and an unclear sexuality pattern that has restricted the breeding of improved strains. We have now sequenced the genome of V. volvacea and assembled it into 62 scaffolds with a total genome size of 35.7 megabases (Mb), containing 11,084 predicted gene models. Comparative analyses were performed with the model species in basidiomycete on mating type system, carbohydrate active enzymes, and fungal oxidative lignin enzymes. We also studied transcriptional regulation of the response to low temperature (4°C). We found that the genome of V. volvacea has many genes that code for enzymes, which are involved in the degradation of cellulose, hemicellulose, and pectin. The molecular genetics of the mating type system in V. volvacea was also found to be similar to the bipolar system in basidiomycetes, suggesting that it is secondary homothallism. Sensitivity to low temperatures could be due to the lack of the initiation of the biosynthesis of unsaturated fatty acids, trehalose and glycogen biosyntheses in this mushroom. Genome sequencing of V. volvacea has improved our understanding of the biological characteristics related to the degradation of the cultivating compost consisting of agricultural waste, the sexual reproduction mechanism, and the sensitivity to low temperatures at the molecular level which in turn will enable us to increase the industrial production of this mushroom. PMID:23526973

Sequencing and comparative analysis of the straw mushroom (Volvariella volvacea genome.

Directory of Open Access Journals (Sweden)

Dapeng Bao

Full Text Available Volvariella volvacea, the edible straw mushroom, is a highly nutritious food source that is widely cultivated on a commercial scale in many parts of Asia using agricultural wastes (rice straw, cotton wastes as growth substrates. However, developments in V. volvacea cultivation have been limited due to a low biological efficiency (i.e. conversion of growth substrate to mushroom fruit bodies, sensitivity to low temperatures, and an unclear sexuality pattern that has restricted the breeding of improved strains. We have now sequenced the genome of V. volvacea and assembled it into 62 scaffolds with a total genome size of 35.7 megabases (Mb, containing 11,084 predicted gene models. Comparative analyses were performed with the model species in basidiomycete on mating type system, carbohydrate active enzymes, and fungal oxidative lignin enzymes. We also studied transcriptional regulation of the response to low temperature (4°C. We found that the genome of V. volvacea has many genes that code for enzymes, which are involved in the degradation of cellulose, hemicellulose, and pectin. The molecular genetics of the mating type system in V. volvacea was also found to be similar to the bipolar system in basidiomycetes, suggesting that it is secondary homothallism. Sensitivity to low temperatures could be due to the lack of the initiation of the biosynthesis of unsaturated fatty acids, trehalose and glycogen biosyntheses in this mushroom. Genome sequencing of V. volvacea has improved our understanding of the biological characteristics related to the degradation of the cultivating compost consisting of agricultural waste, the sexual reproduction mechanism, and the sensitivity to low temperatures at the molecular level which in turn will enable us to increase the industrial production of this mushroom.

Genome-wide identification of regulatory elements and reconstruction of gene regulatory networks of the green alga Chlamydomonas reinhardtii under carbon deprivation.

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Flavia Vischi Winck

Full Text Available The unicellular green alga Chlamydomonas reinhardtii is a long-established model organism for studies on photosynthesis and carbon metabolism-related physiology. Under conditions of air-level carbon dioxide concentration [CO2], a carbon concentrating mechanism (CCM is induced to facilitate cellular carbon uptake. CCM increases the availability of carbon dioxide at the site of cellular carbon fixation. To improve our understanding of the transcriptional control of the CCM, we employed FAIRE-seq (formaldehyde-assisted Isolation of Regulatory Elements, followed by deep sequencing to determine nucleosome-depleted chromatin regions of algal cells subjected to carbon deprivation. Our FAIRE data recapitulated the positions of known regulatory elements in the promoter of the periplasmic carbonic anhydrase (Cah1 gene, which is upregulated during CCM induction, and revealed new candidate regulatory elements at a genome-wide scale. In addition, time series expression patterns of 130 transcription factor (TF and transcription regulator (TR genes were obtained for cells cultured under photoautotrophic condition and subjected to a shift from high to low [CO2]. Groups of co-expressed genes were identified and a putative directed gene-regulatory network underlying the CCM was reconstructed from the gene expression data using the recently developed IOTA (inner composition alignment method. Among the candidate regulatory genes, two members of the MYB-related TF family, Lcr1 (Low-CO 2 response regulator 1 and Lcr2 (Low-CO2 response regulator 2, may play an important role in down-regulating the expression of a particular set of TF and TR genes in response to low [CO2]. The results obtained provide new insights into the transcriptional control of the CCM and revealed more than 60 new candidate regulatory genes. Deep sequencing of nucleosome-depleted genomic regions indicated the presence of new, previously unknown regulatory elements in the C. reinhardtii genome

DMS-Seq for In Vivo Genome-wide Mapping of Protein-DNA Interactions and Nucleosome Centers.

Science.gov (United States)

Umeyama, Taichi; Ito, Takashi

2017-10-03

Protein-DNA interactions provide the basis for chromatin structure and gene regulation. Comprehensive identification of protein-occupied sites is thus vital to an in-depth understanding of genome function. Dimethyl sulfate (DMS) is a chemical probe that has long been used to detect footprints of DNA-bound proteins in vitro and in vivo. Here, we describe a genomic footprinting method, dimethyl sulfate sequencing (DMS-seq), which exploits the cell-permeable nature of DMS to obviate the need for nuclear isolation. This feature makes DMS-seq simple in practice and removes the potential risk of protein re-localization during nuclear isolation. DMS-seq successfully detects transcription factors bound to cis-regulatory elements and non-canonical chromatin particles in nucleosome-free regions. Furthermore, an unexpected preference of DMS confers on DMS-seq a unique potential to directly detect nucleosome centers without using genetic manipulation. We expect that DMS-seq will serve as a characteristic method for genome-wide interrogation of in vivo protein-DNA interactions. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Rodent malaria parasites : genome organization & comparative genomics

NARCIS (Netherlands)

Kooij, Taco W.A.

2006-01-01

The aim of the studies described in this thesis was to investigate the genome organization of rodent malaria parasites (RMPs) and compare the organization and gene content of the genomes of RMPs and the human malaria parasite P. falciparum. The release of the complete genome sequence of P.

Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

Science.gov (United States)

Aranda, Manuel; DeSalvo, Michael K; Bayer, Till; Medina, Monica; Voolstra, Christian R

2012-09-21

Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization). Our results showed that the current microarray platform for A. palmata is able to provide biological relevant information for a wide variety of coral species covering both the complex clade as well the robust clade. Analysis of the fraction of highly diverged genes showed a significantly higher amount of genes without annotation corroborating previous findings that point towards a higher rate of divergence for taxonomically restricted genes. Among the genes with annotation, we found many mitochondrial genes to be highly diverged in M. faveolata when compared to A. palmata, while the majority of nuclear encoded genes maintained an average divergence rate. The use of present microarray platforms for transcriptional analyses in different coral species will greatly enhance the understanding of the molecular basis of stress and health and highlight evolutionary differences between scleractinian coral species. On a genomic basis, we show that cDNA arrays can be used to identify patterns of divergence. Mitochondrion-encoded genes seem to have diverged faster than nuclear encoded genes in robust corals. Accordingly, this

DOT1L and H3K79 Methylation in Transcription and Genomic Stability.

Science.gov (United States)

Wood, Katherine; Tellier, Michael; Murphy, Shona

2018-02-27

The organization of eukaryotic genomes into chromatin provides challenges for the cell to accomplish basic cellular functions, such as transcription, DNA replication and repair of DNA damage. Accordingly, a range of proteins modify and/or read chromatin states to regulate access to chromosomal DNA. Yeast Dot1 and the mammalian homologue DOT1L are methyltransferases that can add up to three methyl groups to histone H3 lysine 79 (H3K79). H3K79 methylation is implicated in several processes, including transcription elongation by RNA polymerase II, the DNA damage response and cell cycle checkpoint activation. DOT1L is also an important drug target for treatment of mixed lineage leukemia (MLL)-rearranged leukemia where aberrant transcriptional activation is promoted by DOT1L mislocalisation. This review summarizes what is currently known about the role of Dot1/DOT1L and H3K79 methylation in transcription and genomic stability.

DOT1L and H3K79 Methylation in Transcription and Genomic Stability

Directory of Open Access Journals (Sweden)

Katherine Wood

2018-02-01

Full Text Available The organization of eukaryotic genomes into chromatin provides challenges for the cell to accomplish basic cellular functions, such as transcription, DNA replication and repair of DNA damage. Accordingly, a range of proteins modify and/or read chromatin states to regulate access to chromosomal DNA. Yeast Dot1 and the mammalian homologue DOT1L are methyltransferases that can add up to three methyl groups to histone H3 lysine 79 (H3K79. H3K79 methylation is implicated in several processes, including transcription elongation by RNA polymerase II, the DNA damage response and cell cycle checkpoint activation. DOT1L is also an important drug target for treatment of mixed lineage leukemia (MLL-rearranged leukemia where aberrant transcriptional activation is promoted by DOT1L mislocalisation. This review summarizes what is currently known about the role of Dot1/DOT1L and H3K79 methylation in transcription and genomic stability.

Defining functional DNA elements in the human genome

Science.gov (United States)

Kellis, Manolis; Wold, Barbara; Snyder, Michael P.; Bernstein, Bradley E.; Kundaje, Anshul; Marinov, Georgi K.; Ward, Lucas D.; Birney, Ewan; Crawford, Gregory E.; Dekker, Job; Dunham, Ian; Elnitski, Laura L.; Farnham, Peggy J.; Feingold, Elise A.; Gerstein, Mark; Giddings, Morgan C.; Gilbert, David M.; Gingeras, Thomas R.; Green, Eric D.; Guigo, Roderic; Hubbard, Tim; Kent, Jim; Lieb, Jason D.; Myers, Richard M.; Pazin, Michael J.; Ren, Bing; Stamatoyannopoulos, John A.; Weng, Zhiping; White, Kevin P.; Hardison, Ross C.

2014-01-01

With the completion of the human genome sequence, attention turned to identifying and annotating its functional DNA elements. As a complement to genetic and comparative genomics approaches, the Encyclopedia of DNA Elements Project was launched to contribute maps of RNA transcripts, transcriptional regulator binding sites, and chromatin states in many cell types. The resulting genome-wide data reveal sites of biochemical activity with high positional resolution and cell type specificity that facilitate studies of gene regulation and interpretation of noncoding variants associated with human disease. However, the biochemically active regions cover a much larger fraction of the genome than do evolutionarily conserved regions, raising the question of whether nonconserved but biochemically active regions are truly functional. Here, we review the strengths and limitations of biochemical, evolutionary, and genetic approaches for defining functional DNA segments, potential sources for the observed differences in estimated genomic coverage, and the biological implications of these discrepancies. We also analyze the relationship between signal intensity, genomic coverage, and evolutionary conservation. Our results reinforce the principle that each approach provides complementary information and that we need to use combinations of all three to elucidate genome function in human biology and disease. PMID:24753594

Genome-wide association study of Tourette's syndrome

NARCIS (Netherlands)

Scharf, J. M.; Yu, D.; Mathews, C. A.; Neale, B. M.; Stewart, S. E.; Fagerness, J. A.; Evans, P.; Gamazon, E.; Edlund, C. K.; Service, S. K.; Tikhomirov, A.; Osiecki, L.; Illmann, C.; Pluzhnikov, A.; Konkashbaev, A.; Davis, L. K.; Han, B.; Crane, J.; Moorjani, P.; Crenshaw, A. T.; Parkin, M. A.; Reus, V. I.; Lowe, T. L.; Rangel-Lugo, M.; Chouinard, S.; Dion, Y.; Girard, S.; Cath, D. C.; Smit, J. H.; King, R. A.; Fernandez, T. V.; Leckman, J. F.; Kidd, K. K.; Kidd, J. R.; Pakstis, A. J.; State, M. W.; Herrera, L. D.; Romero, R.; Fournier, E.; Sandor, P.; Barr, C. L.; Phan, N.; Gross-Tsur, V.; Benarroch, F.; Pollak, Y.; Budman, C. L.; Bruun, R. D.; Erenberg, G.; Naarden, A. L.; Hoekstra, P. J.

2013-01-01

Tourette's syndrome (TS) is a developmental disorder that has one of the highest familial recurrence rates among neuropsychiatric diseases with complex inheritance. However, the identification of definitive TS susceptibility genes remains elusive. Here, we report the first genome-wide association

Embryonic stem cell-like features of testicular carcinoma in situ revealed by genome-wide gene expression profiling.

Science.gov (United States)

Almstrup, Kristian; Hoei-Hansen, Christina E; Wirkner, Ute; Blake, Jonathon; Schwager, Christian; Ansorge, Wilhelm; Nielsen, John E; Skakkebaek, Niels E; Rajpert-De Meyts, Ewa; Leffers, Henrik

2004-07-15

Carcinoma in situ (CIS) is the common precursor of histologically heterogeneous testicular germ cell tumors (TGCTs), which in recent decades have markedly increased and now are the most common malignancy of young men. Using genome-wide gene expression profiling, we identified >200 genes highly expressed in testicular CIS, including many never reported in testicular neoplasms. Expression was further verified by semiquantitative reverse transcription-PCR and in situ hybridization. Among the highest expressed genes were NANOG and POU5F1, and reverse transcription-PCR revealed possible changes in their stoichiometry on progression into embryonic carcinoma. We compared the CIS expression profile with patterns reported in embryonic stem cells (ESCs), which revealed a substantial overlap that may be as high as 50%. We also demonstrated an over-representation of expressed genes in regions of 17q and 12, reported as unstable in cultured ESCs. The close similarity between CIS and ESCs explains the pluripotency of CIS. Moreover, the findings are consistent with an early prenatal origin of TGCTs and thus suggest that etiologic factors operating in utero are of primary importance for the incidence trends of TGCTs. Finally, some of the highly expressed genes identified in this study are promising candidates for new diagnostic markers for CIS and/or TGCTs.

Epigenomics of Total Acute Sleep Deprivation in Relation to Genome-Wide DNA Methylation Profiles and RNA Expression

OpenAIRE

Nilsson, Emil K.; Bostr?m, Adrian E.; Mwinyi, Jessica; Schi?th, Helgi B.

2016-01-01

Abstract Despite an established link between sleep deprivation and epigenetic processes in humans, it remains unclear to what extent sleep deprivation modulates DNA methylation. We performed a within-subject randomized blinded study with 16 healthy subjects to examine the effect of one night of total sleep deprivation (TSD) on the genome-wide methylation profile in blood compared with that in normal sleep. Genome-wide differences in methylation between both conditions were assessed by applyin...

OrthoVenn: a web server for genome wide comparison and annotation of orthologous clusters across multiple species

Science.gov (United States)

Genome wide analysis of orthologous clusters is an important component of comparative genomics studies. Identifying the overlap among orthologous clusters can enable us to elucidate the function and evolution of proteins across multiple species. Here, we report a web platform named OrthoVenn that i...

Systematic discovery of regulatory motifs in Fusarium graminearum by comparing four Fusarium genomes

Directory of Open Access Journals (Sweden)

Kistler Corby

2010-03-01

Full Text Available Abstract Background Fusarium graminearum (Fg, a major fungal pathogen of cultivated cereals, is responsible for billions of dollars in agriculture losses. There is a growing interest in understanding the transcriptional regulation of this organism, especially the regulation of genes underlying its pathogenicity. The generation of whole genome sequence assemblies for Fg and three closely related Fusarium species provides a unique opportunity for such a study. Results Applying comparative genomics approaches, we developed a computational pipeline to systematically discover evolutionarily conserved regulatory motifs in the promoter, downstream and the intronic regions of Fg genes, based on the multiple alignments of sequenced Fusarium genomes. Using this method, we discovered 73 candidate regulatory motifs in the promoter regions. Nearly 30% of these motifs are highly enriched in promoter regions of Fg genes that are associated with a specific functional category. Through comparison to Saccharomyces cerevisiae (Sc and Schizosaccharomyces pombe (Sp, we observed conservation of transcription factors (TFs, their binding sites and the target genes regulated by these TFs related to pathways known to respond to stress conditions or phosphate metabolism. In addition, this study revealed 69 and 39 conserved motifs in the downstream regions and the intronic regions, respectively, of Fg genes. The top intronic motif is the splice donor site. For the downstream regions, we noticed an intriguing absence of the mammalian and Sc poly-adenylation signals among the list of conserved motifs. Conclusion This study provides the first comprehensive list of candidate regulatory motifs in Fg, and underscores the power of comparative genomics in revealing functional elements among related genomes. The conservation of regulatory pathways among the Fusarium genomes and the two yeast species reveals their functional significance, and provides new insights in their

Genome-Wide Meta-Analysis of Longitudinal Alcohol Consumption Across Youth and Early Adulthood.

Science.gov (United States)

Adkins, Daniel E; Clark, Shaunna L; Copeland, William E; Kennedy, Martin; Conway, Kevin; Angold, Adrian; Maes, Hermine; Liu, Youfang; Kumar, Gaurav; Erkanli, Alaattin; Patkar, Ashwin A; Silberg, Judy; Brown, Tyson H; Fergusson, David M; Horwood, L John; Eaves, Lindon; van den Oord, Edwin J C G; Sullivan, Patrick F; Costello, E J

2015-08-01

The public health burden of alcohol is unevenly distributed across the life course, with levels of use, abuse, and dependence increasing across adolescence and peaking in early adulthood. Here, we leverage this temporal patterning to search for common genetic variants predicting developmental trajectories of alcohol consumption. Comparable psychiatric evaluations measuring alcohol consumption were collected in three longitudinal community samples (N=2,126, obs=12,166). Consumption-repeated measurements spanning adolescence and early adulthood were analyzed using linear mixed models, estimating individual consumption trajectories, which were then tested for association with Illumina 660W-Quad genotype data (866,099 SNPs after imputation and QC). Association results were combined across samples using standard meta-analysis methods. Four meta-analysis associations satisfied our pre-determined genome-wide significance criterion (FDR<0.1) and six others met our 'suggestive' criterion (FDR<0.2). Genome-wide significant associations were highly biological plausible, including associations within GABA transporter 1, SLC6A1 (solute carrier family 6, member 1), and exonic hits in LOC100129340 (mitofusin-1-like). Pathway analyses elaborated single marker results, indicating significant enriched associations to intuitive biological mechanisms, including neurotransmission, xenobiotic pharmacodynamics, and nuclear hormone receptors (NHR). These findings underscore the value of combining longitudinal behavioral data and genome-wide genotype information in order to study developmental patterns and improve statistical power in genomic studies.

PeakAnalyzer: Genome-wide annotation of chromatin binding and modification loci

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Tammoja Kairi

2010-08-01

Full Text Available Abstract Background Functional genomic studies involving high-throughput sequencing and tiling array applications, such as ChIP-seq and ChIP-chip, generate large numbers of experimentally-derived signal peaks across the genome under study. In analyzing these loci to determine their potential regulatory functions, areas of signal enrichment must be considered relative to proximal genes and regulatory elements annotated throughout the target genome Regions of chromatin association by transcriptional regulators should be distinguished as individual binding sites in order to enhance downstream analyses, such as the identification of known and novel consensus motifs. Results PeakAnalyzer is a set of high-performance utilities for the automated processing of experimentally-derived peak regions and annotation of genomic loci. The programs can accurately subdivide multimodal regions of signal enrichment into distinct subpeaks corresponding to binding sites or chromatin modifications, retrieve genomic sequences encompassing the computed subpeak summits, and identify positional features of interest such as intersection with exon/intron gene components, proximity to up- or downstream transcriptional start sites and cis-regulatory elements. The software can be configured to run either as a pipeline component for high-throughput analyses, or as a cross-platform desktop application with an intuitive user interface. Conclusions PeakAnalyzer comprises a number of utilities essential for ChIP-seq and ChIP-chip data analysis. High-performance implementations are provided for Unix pipeline integration along with a GUI version for interactive use. Source code in C++ and Java is provided, as are native binaries for Linux, Mac OS X and Windows systems.

Genome-Wide Meta-Analysis of Sciatica in Finnish Population.

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Lemmelä, Susanna; Solovieva, Svetlana; Shiri, Rahman; Benner, Christian; Heliövaara, Markku; Kettunen, Johannes; Anttila, Verneri; Ripatti, Samuli; Perola, Markus; Seppälä, Ilkka; Juonala, Markus; Kähönen, Mika; Salomaa, Veikko; Viikari, Jorma; Raitakari, Olli T; Lehtimäki, Terho; Palotie, Aarno; Viikari-Juntura, Eira; Husgafvel-Pursiainen, Kirsti

2016-01-01

Sciatica or the sciatic syndrome is a common and often disabling low back disorder in the working-age population. It has a relatively high heritability but poorly understood molecular mechanisms. The Finnish population is a genetic isolate where small founder population and bottleneck events have led to enrichment of certain rare and low frequency variants. We performed here the first genome-wide association (GWAS) and meta-analysis of sciatica. The meta-analysis was conducted across two GWAS covering 291 Finnish sciatica cases and 3671 controls genotyped and imputed at 7.7 million autosomal variants. The most promising loci (psciatica patients and 18,489 controls. We identified five intragenic variants, with relatively low frequencies, at two novel loci associated with sciatica at genome-wide significance. These included chr9:14344410:I (rs71321981) at 9p22.3 (NFIB gene; p = 1.30x10-8, MAF = 0.08) and four variants at 15q21.2: rs145901849, rs80035109, rs190200374 and rs117458827 (MYO5A; p = 1.34x10-8, MAF = 0.06; p = 2.32x10-8, MAF = 0.07; p = 3.85x10-8, MAF = 0.06; p = 4.78x10-8, MAF = 0.07, respectively). The most significant association in the meta-analysis, a single base insertion rs71321981 within the regulatory region of the transcription factor NFIB, replicated in an independent Finnish population sample (p = 0.04). Despite identifying 15q21.2 as a promising locus, we were not able to replicate it. It was differentiated; the lead variants within 15q21.2 were more frequent in Finland (6-7%) than in other European populations (1-2%). Imputation accuracies of the three significantly associated variants (chr9:14344410:I, rs190200374, and rs80035109) were validated by genotyping. In summary, our results suggest a novel locus, 9p22.3 (NFIB), which may be involved in susceptibility to sciatica. In addition, another locus, 15q21.2, emerged as a promising one, but failed to replicate.

Genome analysis and comparative genomics of a Giardia intestinalis assemblage E isolate

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Andersson Jan O

2010-10-01

Full Text Available Abstract Background Giardia intestinalis is a protozoan parasite that causes diarrhea in a wide range of mammalian species. To further understand the genetic diversity between the Giardia intestinalis species, we have performed genome sequencing and analysis of a wild-type Giardia intestinalis sample from the assemblage E group, isolated from a pig. Results We identified 5012 protein coding genes, the majority of which are conserved compared to the previously sequenced genomes of the WB and GS strains in terms of microsynteny and sequence identity. Despite this, there is an unexpectedly large number of chromosomal rearrangements and several smaller structural changes that are present in all chromosomes. Novel members of the VSP, NEK Kinase and HCMP gene families were identified, which may reveal possible mechanisms for host specificity and new avenues for antigenic variation. We used comparative genomics of the three diverse Giardia intestinalis isolates P15, GS and WB to define a core proteome for this species complex and to identify lineage-specific genes. Extensive analyses of polymorphisms in the core proteome of Giardia revealed differential rates of divergence among cellular processes. Conclusions Our results indicate that despite a well conserved core of genes there is significant genome variation between Giardia isolates, both in terms of gene content, gene polymorphisms, structural chromosomal variations and surface molecule repertoires. This study improves the annotation of the Giardia genomes and enables the identification of functionally important variation.

Genome-wide occupancy profile of mediator and the Srb8-11 module reveals interactions with coding regions

DEFF Research Database (Denmark)

Zhu, Xuefeng; Wirén, Marianna; Sinha, Indranil

2006-01-01

Mediator exists in a free form containing the Med12, Med13, CDK8, and CycC subunits (the Srb8-11 module) and a smaller form, which lacks these four subunits and associates with RNA polymerase II (Pol II), forming a holoenzyme. We use chromatin immunoprecipitation (ChIP) and DNA microarrays...... to investigate genome-wide localization of Mediator and the Srb8-11 module in fission yeast. Mediator and the Srb8-11 module display similar binding patterns, and interactions with promoters and upstream activating sequences correlate with increased transcription activity. Unexpectedly, Mediator also interacts...... with the downstream coding region of many genes. These interactions display a negative bias for positions closer to the 5' ends of open reading frames (ORFs) and appear functionally important, because downregulation of transcription in a temperature-sensitive med17 mutant strain correlates with increased Mediator...

Genome-wide linkage analysis for human longevity

DEFF Research Database (Denmark)

Beekman, Marian; Blanché, Hélène; Perola, Markus

2013-01-01

Clear evidence exists for heritability of human longevity, and much interest is focused on identifying genes associated with longer lives. To identify such longevity alleles, we performed the largest genome-wide linkage scan thus far reported. Linkage analyses included 2118 nonagenarian Caucasian...

Hierarchical role for transcription factors and chromatin structure in genome organization along adipogenesis

DEFF Research Database (Denmark)

Sarusi Portuguez, Avital; Schwartz, Michal; Siersbaek, Rasmus

2017-01-01

The three dimensional folding of mammalian genomes is cell type specific and difficult to alter suggesting that it is an important component of gene regulation. However, given the multitude of chromatin-associating factors, the mechanisms driving the colocalization of active chromosomal domains...... by PPARγ and Lpin1, undergoes orchestrated reorganization during adipogenesis. Coupling the dynamics of genome architecture with multiple chromatin datasets indicated that among all the transcription factors (TFs) tested, RXR is central to genome reorganization at the beginning of adipogenesis...

Genome-wide strategies identify downstream target genes of chick connective tissue-associated transcription factors.

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Orgeur, Mickael; Martens, Marvin; Leonte, Georgeta; Nassari, Sonya; Bonnin, Marie-Ange; Börno, Stefan T; Timmermann, Bernd; Hecht, Jochen; Duprez, Delphine; Stricker, Sigmar

2018-03-29

Connective tissues support organs and play crucial roles in development, homeostasis and fibrosis, yet our understanding of their formation is still limited. To gain insight into the molecular mechanisms of connective tissue specification, we selected five zinc-finger transcription factors - OSR1, OSR2, EGR1, KLF2 and KLF4 - based on their expression patterns and/or known involvement in connective tissue subtype differentiation. RNA-seq and ChIP-seq profiling of chick limb micromass cultures revealed a set of common genes regulated by all five transcription factors, which we describe as a connective tissue core expression set. This common core was enriched with genes associated with axon guidance and myofibroblast signature, including fibrosis-related genes. In addition, each transcription factor regulated a specific set of signalling molecules and extracellular matrix components. This suggests a concept whereby local molecular niches can be created by the expression of specific transcription factors impinging on the specification of local microenvironments. The regulatory network established here identifies common and distinct molecular signatures of limb connective tissue subtypes, provides novel insight into the signalling pathways governing connective tissue specification, and serves as a resource for connective tissue development. © 2018. Published by The Company of Biologists Ltd.

Genome-wide characterization of the SiDof gene family in foxtail millet (Setaria italica).

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Zhang, Li; Liu, Baoling; Zheng, Gewen; Zhang, Aiying; Li, Runzhi

2017-01-01

Dof (DNA binding with one finger) proteins, which constitute a class of transcription factors found exclusively in plants, are involved in numerous physiological and biochemical reactions affecting growth and development. A genome-wide analysis of SiDof genes was performed in this study. Thirty five SiDof genes were identified and those genes were unevenly distributed across nine chromosomes in the Seteria italica genome. Protein lengths, molecular weights, and theoretical isoelectric points of SiDofs all vary greatly. Gene structure analysis demonstrated that most SiDof genes lack introns. Phylogenetic analysis of SiDof proteins and Dof proteins from Arabidopsis thaliana, rice, sorghum, and Setaria viridis revealed six major groups. Analysis of RNA-Seq data indicated that SiDof gene expression levels varied across roots, stems, leaves, and spike. In addition, expression profiling of SiDof genes in response to stress suggested that SiDof 7 and SiDof 15 are involved in drought stress signalling. Overall, this study could provide novel information on SiDofs for further investigation in foxtail millet. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genome-wide association studies (GWAS) of adiposity

DEFF Research Database (Denmark)

Oskari Kilpeläinen, Tuomas; Ingelsson, Erik

2016-01-01

Adiposity is strongly heritable and one of the leading risk factors for type 2 diabetes, cardiovascular disease, cancer, and premature death. In the past 8 years, genome-wide association studies (GWAS) have greatly increased our understanding of the genes and biological pathways that regulate...

Genome-wide annotation of the soybean WRKY family and functional characterization of genes involved in response to Phakopsora pachyrhizi infection.

Science.gov (United States)

Bencke-Malato, Marta; Cabreira, Caroline; Wiebke-Strohm, Beatriz; Bücker-Neto, Lauro; Mancini, Estefania; Osorio, Marina B; Homrich, Milena S; Turchetto-Zolet, Andreia Carina; De Carvalho, Mayra C C G; Stolf, Renata; Weber, Ricardo L M; Westergaard, Gastón; Castagnaro, Atílio P; Abdelnoor, Ricardo V; Marcelino-Guimarães, Francismar C; Margis-Pinheiro, Márcia; Bodanese-Zanettini, Maria Helena

2014-09-10

Many previous studies have shown that soybean WRKY transcription factors are involved in the plant response to biotic and abiotic stresses. Phakopsora pachyrhizi is the causal agent of Asian Soybean Rust, one of the most important soybean diseases. There are evidences that WRKYs are involved in the resistance of some soybean genotypes against that fungus. The number of WRKY genes already annotated in soybean genome was underrepresented. In the present study, a genome-wide annotation of the soybean WRKY family was carried out and members involved in the response to P. pachyrhizi were identified. As a result of a soybean genomic databases search, 182 WRKY-encoding genes were annotated and 33 putative pseudogenes identified. Genes involved in the response to P. pachyrhizi infection were identified using superSAGE, RNA-Seq of microdissected lesions and microarray experiments. Seventy-five genes were differentially expressed during fungal infection. The expression of eight WRKY genes was validated by RT-qPCR. The expression of these genes in a resistant genotype was earlier and/or stronger compared with a susceptible genotype in response to P. pachyrhizi infection. Soybean somatic embryos were transformed in order to overexpress or silence WRKY genes. Embryos overexpressing a WRKY gene were obtained, but they were unable to convert into plants. When infected with P. pachyrhizi, the leaves of the silenced transgenic line showed a higher number of lesions than the wild-type plants. The present study reports a genome-wide annotation of soybean WRKY family. The participation of some members in response to P. pachyrhizi infection was demonstrated. The results contribute to the elucidation of gene function and suggest the manipulation of WRKYs as a strategy to increase fungal resistance in soybean plants.

Meta-analysis of Genome-Wide Association Studies for Extraversion

DEFF Research Database (Denmark)

van den Berg, Stéphanie M; de Moor, Marleen H M; Verweij, K. J. H.

2016-01-01

small sample sizes of those studies. Here, we report on a large meta-analysis of GWA studies for extraversion in 63,030 subjects in 29 cohorts. Extraversion item data from multiple personality inventories were harmonized across inventories and cohorts. No genome-wide significant associations were found...... at the single nucleotide polymorphism (SNP) level but there was one significant hit at the gene level for a long non-coding RNA site (LOC101928162). Genome-wide complex trait analysis in two large cohorts showed that the additive variance explained by common SNPs was not significantly different from zero...

CoryneRegNet: an ontology-based data warehouse of corynebacterial transcription factors and regulatory networks.

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Baumbach, Jan; Brinkrolf, Karina; Czaja, Lisa F; Rahmann, Sven; Tauch, Andreas

2006-02-14

The application of DNA microarray technology in post-genomic analysis of bacterial genome sequences has allowed the generation of huge amounts of data related to regulatory networks. This data along with literature-derived knowledge on regulation of gene expression has opened the way for genome-wide reconstruction of transcriptional regulatory networks. These large-scale reconstructions can be converted into in silico models of bacterial cells that allow a systematic analysis of network behavior in response to changing environmental conditions. CoryneRegNet was designed to facilitate the genome-wide reconstruction of transcriptional regulatory networks of corynebacteria relevant in biotechnology and human medicine. During the import and integration process of data derived from experimental studies or literature knowledge CoryneRegNet generates links to genome annotations, to identified transcription factors and to the corresponding cis-regulatory elements. CoryneRegNet is based on a multi-layered, hierarchical and modular concept of transcriptional regulation and was implemented by using the relational database management system MySQL and an ontology-based data structure. Reconstructed regulatory networks can be visualized by using the yFiles JAVA graph library. As an application example of CoryneRegNet, we have reconstructed the global transcriptional regulation of a cellular module involved in SOS and stress response of corynebacteria. CoryneRegNet is an ontology-based data warehouse that allows a pertinent data management of regulatory interactions along with the genome-scale reconstruction of transcriptional regulatory networks. These models can further be combined with metabolic networks to build integrated models of cellular function including both metabolism and its transcriptional regulation.

Multimode drug inducible CRISPR/Cas9 devices for transcriptional activation and genome editing

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Lu, Jia; Zhao, Chen; Zhao, Yingze; Zhang, Jingfang; Zhang, Yue; Chen, Li; Han, Qiyuan; Ying, Yue; Peng, Shuai; Ai, Runna; Wang, Yu

2018-01-01

Abstract Precise investigation and manipulation of dynamic biological processes often requires molecular modulation in a controlled inducible manner. The clustered, regularly interspaced, short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) has emerged as a versatile tool for targeted gene editing and transcriptional programming. Here, we designed and vigorously optimized a series of Hybrid drug Inducible CRISPR/Cas9 Technologies (HIT) for transcriptional activation by grafting a mutated human estrogen receptor (ERT2) to multiple CRISPR/Cas9 systems, which renders them 4-hydroxytamoxifen (4-OHT) inducible for the access of genome. Further, extra functionality of simultaneous genome editing was achieved with one device we named HIT2. Optimized terminal devices herein delivered advantageous performances in comparison with several existing designs. They exerted selective, titratable, rapid and reversible response to drug induction. In addition, these designs were successfully adapted to an orthogonal Cas9. HIT systems developed in this study can be applied for controlled modulation of potentially any genomic loci in multiple modes. PMID:29237052

Genome wide identification of aberrant alternative splicing events in myotonic dystrophy type 2.

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Perfetti, Alessandra; Greco, Simona; Fasanaro, Pasquale; Bugiardini, Enrico; Cardani, Rosanna; Garcia-Manteiga, Jose M; Manteiga, Jose M Garcia; Riba, Michela; Cittaro, Davide; Stupka, Elia; Meola, Giovanni; Martelli, Fabio

2014-01-01

Myotonic dystrophy type 2 (DM2) is a genetic, autosomal dominant disease due to expansion of tetraplet (CCTG) repetitions in the first intron of the ZNF9/CNBP gene. DM2 is a multisystemic disorder affecting the skeletal muscle, the heart, the eye and the endocrine system. According to the proposed pathological mechanism, the expanded tetraplets have an RNA toxic effect, disrupting the splicing of many mRNAs. Thus, the identification of aberrantly spliced transcripts is instrumental for our understanding of the molecular mechanisms underpinning the disease. The aim of this study was the identification of new aberrant alternative splicing events in DM2 patients. By genome wide analysis of 10 DM2 patients and 10 controls (CTR), we identified 273 alternative spliced exons in 218 genes. While many aberrant splicing events were already identified in the past, most were new. A subset of these events was validated by qPCR assays in 19 DM2 and 15 CTR subjects. To gain insight into the molecular pathways involving the identified aberrantly spliced genes, we performed a bioinformatics analysis with Ingenuity system. This analysis indicated a deregulation of development, cell survival, metabolism, calcium signaling and contractility. In conclusion, our genome wide analysis provided a database of aberrant splicing events in the skeletal muscle of DM2 patients. The affected genes are involved in numerous pathways and networks important for muscle physio-pathology, suggesting that the identified variants may contribute to DM2 pathogenesis.

The Glyphosate-Based Herbicide Roundup Does not Elevate Genome-Wide Mutagenesis of Escherichia coli.

Science.gov (United States)

Tincher, Clayton; Long, Hongan; Behringer, Megan; Walker, Noah; Lynch, Michael

2017-10-05

Mutations induced by pollutants may promote pathogen evolution, for example by accelerating mutations conferring antibiotic resistance. Generally, evaluating the genome-wide mutagenic effects of long-term sublethal pollutant exposure at single-nucleotide resolution is extremely difficult. To overcome this technical barrier, we use the mutation accumulation/whole-genome sequencing (MA/WGS) method as a mutagenicity test, to quantitatively evaluate genome-wide mutagenesis of Escherichia coli after long-term exposure to a wide gradient of the glyphosate-based herbicide (GBH) Roundup Concentrate Plus. The genome-wide mutation rate decreases as GBH concentration increases, suggesting that even long-term GBH exposure does not compromise the genome stability of bacteria. Copyright © 2017 Tincher et al.

Genome-wide comparison of paired fresh frozen and formalin-fixed paraffin-embedded gliomas by custom BAC and oligonucleotide array comparative genomic hybridization: facilitating analysis of archival gliomas

Science.gov (United States)

Mohapatra, Gayatry; Engler, David A.; Starbuck, Kristen D.; Kim, James C.; Bernay, Derek C.; Scangas, George A.; Rousseau, Audrey; Batchelor, Tracy T.; Betensky, Rebecca A.; Louis, David N.

2010-01-01

Molecular genetic analysis of cancer is rapidly evolving as a result of improvement in genomic technologies and the growing applicability of such analyses to clinical oncology. Array based comparative genomic hybridization (aCGH) is a powerful tool for detecting DNA copy number alterations (CNA), particularly in solid tumors, and has been applied to the study of malignant gliomas. In the clinical setting, however, gliomas are often sampled by small biopsies and thus formalin-fixed paraffin-embedded (FFPE) blocks are often the only tissue available for genetic analysis, especially for rare types of gliomas. Moreover, the biological basis for the marked intratumoral heterogeneity in gliomas is most readily addressed in FFPE material. Therefore, for gliomas, the ability to use DNA from FFPE tissue is essential for both clinical and research applications. In this study, we have constructed a custom bacterial artificial chromosome (BAC) array and show excellent sensitivity and specificity for detecting CNAs in a panel of paired frozen and FFPE glioma samples. Our study demonstrates a high concordance rate between CNAs detected in FFPE compared to frozen DNA. We have also developed a method of labeling DNA from FFPE tissue that allows efficient hybridization to oligonucleotide arrays. This labeling technique was applied to a panel of biphasic anaplastic oligoastrocytomas (AOA) to identify genetic changes unique to each component. Together, results from these studies suggest that BAC and oligonucleotide aCGH are sensitive tools for detecting CNAs in FFPE DNA, and can enable genome-wide analysis of rare, small and/or histologically heterogeneous gliomas. PMID:21080181

Genome-wide expression analysis of salt-stressed diploid and autotetraploid Paulownia tomentosa.

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Zhenli Zhao

Full Text Available Paulownia tomentosa is a fast-growing tree species with multiple uses. It is grown worldwide, but is native to China, where it is widely cultivated in saline regions. We previously confirmed that autotetraploid P. tomentosa plants are more stress-tolerant than the diploid plants. However, the molecular mechanism underlying P. tomentosa salinity tolerance has not been fully characterized. Using the complete Paulownia fortunei genome as a reference, we applied next-generation RNA-sequencing technology to analyze the effects of salt stress on diploid and autotetraploid P. tomentosa plants. We generated 175 million clean reads and identified 15,873 differentially expressed genes (DEGs from four P. tomentosa libraries (two diploid and two autotetraploid. Functional annotations of the differentially expressed genes using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases revealed that plant hormone signal transduction and photosynthetic activities are vital for plant responses to high-salt conditions. We also identified several transcription factors, including members of the AP2/EREBP, bHLH, MYB, and NAC families. Quantitative real-time PCR analysis validated the expression patterns of eight differentially expressed genes. Our findings and the generated transcriptome data may help to accelerate the genetic improvement of cultivated P. tomentosa and other plant species for enhanced growth in saline soils.

RNA-Seq-Based Transcript Structure Analysis with TrBorderExt.

Science.gov (United States)

Wang, Yejun; Sun, Ming-An; White, Aaron P

2018-01-01

RNA-Seq has become a routine strategy for genome-wide gene expression comparisons in bacteria. Despite lower resolution in transcript border parsing compared with dRNA-Seq, TSS-EMOTE, Cappable-seq, Term-seq, and others, directional RNA-Seq still illustrates its advantages: low cost, quantification and transcript border analysis with a medium resolution (±10-20 nt). To facilitate mining of directional RNA-Seq datasets especially with respect to transcript structure analysis, we developed a tool, TrBorderExt, which can parse transcript start sites and termination sites accurately in bacteria. A detailed protocol is described in this chapter for how to use the software package step by step to identify bacterial transcript borders from raw RNA-Seq data. The package was developed with Perl and R programming languages, and is accessible freely through the website: http://www.szu-bioinf.org/TrBorderExt .

Genome-wide and gene-based association studies of anxiety disorders in European and African American samples.

Directory of Open Access Journals (Sweden)

Takeshi Otowa

Full Text Available Anxiety disorders (ADs are common mental disorders caused by a combination of genetic and environmental factors. Since ADs are highly comorbid with each other, partially due to shared genetic basis, studying AD phenotypes in a coordinated manner may be a powerful strategy for identifying potential genetic loci for ADs. To detect these loci, we performed genome-wide association studies (GWAS of ADs. In addition, as a complementary approach to single-locus analysis, we also conducted gene- and pathway-based analyses. GWAS data were derived from the control sample of the Molecular Genetics of Schizophrenia (MGS project (2,540 European American and 849 African American subjects genotyped on the Affymetrix GeneChip 6.0 array. We applied two phenotypic approaches: (1 categorical case-control comparisons (CC based upon psychiatric diagnoses, and (2 quantitative phenotypic factor scores (FS derived from a multivariate analysis combining information across the clinical phenotypes. Linear and logistic models were used to analyse the association with ADs using FS and CC traits, respectively. At the single locus level, no genome-wide significant association was found. A trans-population gene-based meta-analysis across both ethnic subsamples using FS identified three genes (MFAP3L on 4q32.3, NDUFAB1 and PALB2 on 16p12 with genome-wide significance (false discovery rate (FDR] <5%. At the pathway level, several terms such as transcription regulation, cytokine binding, and developmental process were significantly enriched in ADs (FDR <5%. Our approaches studying ADs as quantitative traits and utilizing the full GWAS data may be useful in identifying susceptibility genes and pathways for ADs.

Genome-wide analysis of Polycomb targets in Drosophila

Energy Technology Data Exchange (ETDEWEB)

Schwartz, Yuri B.; Kahn, Tatyana G.; Nix, David A.; Li,Xiao-Yong; Bourgon, Richard; Biggin, Mark; Pirrotta, Vincenzo

2006-04-01

Polycomb Group (PcG) complexes are multiprotein assemblages that bind to chromatin and establish chromatin states leading to epigenetic silencing. PcG proteins regulate homeotic genes in flies and vertebrates but little is known about other PcG targets and the role of the PcG in development, differentiation and disease. We have determined the distribution of the PcG proteins PC, E(Z) and PSC and of histone H3K27 trimethylation in the Drosophila genome. At more than 200 PcG target genes, binding sites for the three PcG proteins colocalize to presumptive Polycomb Response Elements (PREs). In contrast, H3 me3K27 forms broad domains including the entire transcription unit and regulatory regions. PcG targets are highly enriched in genes encoding transcription factors but receptors, signaling proteins, morphogens and regulators representing all major developmental pathways are also included.

Genome wide gene expression regulation by HIP1 Protein Interactor, HIPPI: Prediction and validation

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Lahiri Ansuman

2011-09-01

Full Text Available Abstract Background HIP1 Protein Interactor (HIPPI is a pro-apoptotic protein that induces Caspase8 mediated apoptosis in cell. We have shown earlier that HIPPI could interact with a specific 9 bp sequence motif, defined as the HIPPI binding site (HBS, present in the upstream promoter of Caspase1 gene and regulate its expression. We also have shown that HIPPI, without any known nuclear localization signal, could be transported to the nucleus by HIP1, a NLS containing nucleo-cytoplasmic shuttling protein. Thus our present work aims at the investigation of the role of HIPPI as a global transcription regulator. Results We carried out genome wide search for the presence of HBS in the upstream sequences of genes. Our result suggests that HBS was predominantly located within 2 Kb upstream from transcription start site. Transcription factors like CREBP1, TBP, OCT1, EVI1 and P53 half site were significantly enriched in the 100 bp vicinity of HBS indicating that they might co-operate with HIPPI for transcription regulation. To illustrate the role of HIPPI on transcriptome, we performed gene expression profiling by microarray. Exogenous expression of HIPPI in HeLa cells resulted in up-regulation of 580 genes (p HIP1 was knocked down. HIPPI-P53 interaction was necessary for HIPPI mediated up-regulation of Caspase1 gene. Finally, we analyzed published microarray data obtained with post mortem brains of Huntington's disease (HD patients to investigate the possible involvement of HIPPI in HD pathogenesis. We observed that along with the transcription factors like CREB, P300, SREBP1, Sp1 etc. which are already known to be involved in HD, HIPPI binding site was also significantly over-represented in the upstream sequences of genes altered in HD. Conclusions Taken together, the results suggest that HIPPI could act as an important transcription regulator in cell regulating a vast array of genes, particularly transcription factors and at least, in part, play a

NSD1 mutations generate a genome-wide DNA methylation signature.

LENUS (Irish Health Repository)

Choufani, S

2015-12-22

Sotos syndrome (SS) represents an important human model system for the study of epigenetic regulation; it is an overgrowth\\/intellectual disability syndrome caused by mutations in a histone methyltransferase, NSD1. As layered epigenetic modifications are often interdependent, we propose that pathogenic NSD1 mutations have a genome-wide impact on the most stable epigenetic mark, DNA methylation (DNAm). By interrogating DNAm in SS patients, we identify a genome-wide, highly significant NSD1(+\\/-)-specific signature that differentiates pathogenic NSD1 mutations from controls, benign NSD1 variants and the clinically overlapping Weaver syndrome. Validation studies of independent cohorts of SS and controls assigned 100% of these samples correctly. This highly specific and sensitive NSD1(+\\/-) signature encompasses genes that function in cellular morphogenesis and neuronal differentiation, reflecting cardinal features of the SS phenotype. The identification of SS-specific genome-wide DNAm alterations will facilitate both the elucidation of the molecular pathophysiology of SS and the development of improved diagnostic testing.

A Herpesviral Immediate Early Protein Promotes Transcription Elongation of Viral Transcripts.

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Fox, Hannah L; Dembowski, Jill A; DeLuca, Neal A

2017-06-13

Herpes simplex virus 1 (HSV-1) genes are transcribed by cellular RNA polymerase II (RNA Pol II). While four viral immediate early proteins (ICP4, ICP0, ICP27, and ICP22) function in some capacity in viral transcription, the mechanism by which ICP22 functions remains unclear. We observed that the FACT complex (comprised of SSRP1 and Spt16) was relocalized in infected cells as a function of ICP22. ICP22 was also required for the association of FACT and the transcription elongation factors SPT5 and SPT6 with viral genomes. We further demonstrated that the FACT complex interacts with ICP22 throughout infection. We therefore hypothesized that ICP22 recruits cellular transcription elongation factors to viral genomes for efficient transcription elongation of viral genes. We reevaluated the phenotype of an ICP22 mutant virus by determining the abundance of all viral mRNAs throughout infection by transcriptome sequencing (RNA-seq). The accumulation of almost all viral mRNAs late in infection was reduced compared to the wild type, regardless of kinetic class. Using chromatin immunoprecipitation sequencing (ChIP-seq), we mapped the location of RNA Pol II on viral genes and found that RNA Pol II levels on the bodies of viral genes were reduced in the ICP22 mutant compared to wild-type virus. In contrast, the association of RNA Pol II with transcription start sites in the mutant was not reduced. Taken together, our results indicate that ICP22 plays a role in recruiting elongation factors like the FACT complex to the HSV-1 genome to allow for efficient viral transcription elongation late in viral infection and ultimately infectious virion production. IMPORTANCE HSV-1 interacts with many cellular proteins throughout productive infection. Here, we demonstrate the interaction of a viral protein, ICP22, with a subset of cellular proteins known to be involved in transcription elongation. We determined that ICP22 is required to recruit the FACT complex and other transcription

Development and Integration of Genome-Wide Polymorphic Microsatellite Markers onto a Reference Linkage Map for Constructing a High-Density Genetic Map of Chickpea.

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Yash Paul Khajuria

Full Text Available The identification of informative in silico polymorphic genomic and genic microsatellite markers by comparing the genome and transcriptome sequences of crop genotypes is a rapid, cost-effective and non-laborious approach for large-scale marker validation and genotyping applications, including construction of high-density genetic maps. We designed 1494 markers, including 1016 genomic and 478 transcript-derived microsatellite markers showing in-silico fragment length polymorphism between two parental genotypes (Cicer arietinum ICC4958 and C. reticulatum PI489777 of an inter-specific reference mapping population. High amplification efficiency (87%, experimental validation success rate (81% and polymorphic potential (55% of these microsatellite markers suggest their effective use in various applications of chickpea genetics and breeding. Intra-specific polymorphic potential (48% detected by microsatellite markers in 22 desi and kabuli chickpea genotypes was lower than inter-specific polymorphic potential (59%. An advanced, high-density, integrated and inter-specific chickpea genetic map (ICC4958 x PI489777 having 1697 map positions spanning 1061.16 cM with an average inter-marker distance of 0.625 cM was constructed by assigning 634 novel informative transcript-derived and genomic microsatellite markers on eight linkage groups (LGs of our prior documented, 1063 marker-based genetic map. The constructed genome map identified 88, including four major (7-23 cM longest high-resolution genomic regions on LGs 3, 5 and 8, where the maximum number of novel genomic and genic microsatellite markers were specifically clustered within 1 cM genetic distance. It was for the first time in chickpea that in silico FLP analysis at genome-wide level was carried out and such a large number of microsatellite markers were identified, experimentally validated and further used in genetic mapping. To best of our knowledge, in the presently constructed genetic map, we mapped

Comparative genomics of toxigenic and non-toxigenic Staphylococcus hyicus

DEFF Research Database (Denmark)

Leekitcharoenphon, Pimlapas; Pamp, Sünje Johanna; Andresen, Lars Ole

2016-01-01

The most common causative agent of exudative epidermitis (EE) in pigs is Staphylococcus hyicus. S. hyicus can be grouped into toxigenic and non-toxigenic strains based on their ability to cause EE in pigs and specific virulence genes have been identified. A genome wide comparison between non......-toxigenic and toxigenic strains has never been performed. In this study, we sequenced eleven toxigenic and six non-toxigenic S. hyicus strains and performed comparative genomic and phylogenetic analysis. Our analyses revealed two genomic regions encoding genes that were predominantly found in toxigenic strains...... (polymorphic toxin) and was associated with the gene encoding ExhA. A clear differentiation between toxigenic and non-toxigenic strains based on genomic and phylogenetic analyses was not apparent. The results of this study support the observation that exfoliative toxins of S. hyicus and S. aureus are located...

Genome-Wide Association Study and Linkage Analysis of the Healthy Aging Index

DEFF Research Database (Denmark)

Minster, Ryan L; Sanders, Jason L; Singh, Jatinder

2015-01-01

BACKGROUND: The Healthy Aging Index (HAI) is a tool for measuring the extent of health and disease across multiple systems. METHODS: We conducted a genome-wide association study and a genome-wide linkage analysis to map quantitative trait loci associated with the HAI and a modified HAI weighted...

GEM System: automatic prototyping of cell-wide metabolic pathway models from genomes

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Nakayama Yoichi

2006-03-01

Full Text Available Abstract Background Successful realization of a "systems biology" approach to analyzing cells is a grand challenge for our understanding of life. However, current modeling approaches to cell simulation are labor-intensive, manual affairs, and therefore constitute a major bottleneck in the evolution of computational cell biology. Results We developed the Genome-based Modeling (GEM System for the purpose of automatically prototyping simulation models of cell-wide metabolic pathways from genome sequences and other public biological information. Models generated by the GEM System include an entire Escherichia coli metabolism model comprising 968 reactions of 1195 metabolites, achieving 100% coverage when compared with the KEGG database, 92.38% with the EcoCyc database, and 95.06% with iJR904 genome-scale model. Conclusion The GEM System prototypes qualitative models to reduce the labor-intensive tasks required for systems biology research. Models of over 90 bacterial genomes are available at our web site.

A comparison of multivariate genome-wide association methods

DEFF Research Database (Denmark)

Galesloot, Tessel E; Van Steen, Kristel; Kiemeney, Lambertus A L M

2014-01-01

Joint association analysis of multiple traits in a genome-wide association study (GWAS), i.e. a multivariate GWAS, offers several advantages over analyzing each trait in a separate GWAS. In this study we directly compared a number of multivariate GWAS methods using simulated data. We focused on six...... methods that are implemented in the software packages PLINK, SNPTEST, MultiPhen, BIMBAM, PCHAT and TATES, and also compared them to standard univariate GWAS, analysis of the first principal component of the traits, and meta-analysis of univariate results. We simulated data (N = 1000) for three...... for scenarios with an opposite sign of genetic and residual correlation. All multivariate analyses resulted in a higher power than univariate analyses, even when only one of the traits was associated with the QTL. Hence, use of multivariate GWAS methods can be recommended, even when genetic correlations between...

A system-level model for the microbial regulatory genome.

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Brooks, Aaron N; Reiss, David J; Allard, Antoine; Wu, Wei-Ju; Salvanha, Diego M; Plaisier, Christopher L; Chandrasekaran, Sriram; Pan, Min; Kaur, Amardeep; Baliga, Nitin S

2014-07-15

Microbes can tailor transcriptional responses to diverse environmental challenges despite having streamlined genomes and a limited number of regulators. Here, we present data-driven models that capture the dynamic interplay of the environment and genome-encoded regulatory programs of two types of prokaryotes: Escherichia coli (a bacterium) and Halobacterium salinarum (an archaeon). The models reveal how the genome-wide distributions of cis-acting gene regulatory elements and the conditional influences of transcription factors at each of those elements encode programs for eliciting a wide array of environment-specific responses. We demonstrate how these programs partition transcriptional regulation of genes within regulons and operons to re-organize gene-gene functional associations in each environment. The models capture fitness-relevant co-regulation by different transcriptional control mechanisms acting across the entire genome, to define a generalized, system-level organizing principle for prokaryotic gene regulatory networks that goes well beyond existing paradigms of gene regulation. An online resource (http://egrin2.systemsbiology.net) has been developed to facilitate multiscale exploration of conditional gene regulation in the two prokaryotes. © 2014 The Authors. Published under the terms of the CC BY 4.0 license.

Genome-wide divergence, haplotype distribution and population demographic histories for Gossypium hirsutum and Gossypium barbadense as revealed by genome-anchored SNPs

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Use of 10,129 singleton SNPs of known genomic location in tetraploid cotton provided unique opportunities to characterize genome-wide diversity among 440 Gossypium hirsutum and 219 G. barbadense cultivars and landrace accessions of widespread origin. Using the SNPs distributed genome-wide, we exami...

Transcriptional profiling of nitrogen fixation and the role of NifA in the diazotrophic endophyte Azoarcus sp. strain BH72.

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Abhijit Sarkar

Full Text Available BACKGROUND: The model endophyte Azoarcus sp. strain BH72 is known to contribute fixed nitrogen to its host Kallar grass and also expresses nitrogenase genes endophytically in rice seedlings. Availability of nitrogen is a signal regulating the transcription of nitrogenase genes. Therefore, we analysed global transcription in response to differences in the nitrogen source. METHODOLOGY/PRINCIPAL FINDINGS: A DNA microarray, comprising 70-mer oligonucleotides representing 3989 open reading frames of the genome of strain BH72, was used for transcriptome studies. Transcription profiles of cells grown microaerobically on N2 versus ammonium were compared. Expression of 7.2% of the genes was significantly up-regulated, and 5.8% down-regulated upon N2 fixation, respectively. A parallel genome-wide prediction of σ(54-type promoter elements mapped to the upstream region of 38 sequences of which 36 were modulated under the N2 response. In addition to modulation of genes related to N2 fixation, the expressions of gene clusters that might be related to plant-microbe interaction and of several transcription factors were significantly enhanced. While comparing under N2-fixation conditions the transcriptome of wild type with a nifLA(- insertion mutant, NifA being the essential transcriptional activator for nif genes, 24.5% of the genome was found to be affected in expression. A genome-wide prediction of 29 NifA binding sequences matched to 25 of the target genes whose expression was differential during microarray analysis, some of which were putatively negatively regulated by NifA. For selected genes, differential expression was corroborated by real time RT-PCR studies. CONCLUSION/SIGNIFICANCE: Our data suggest that life under conditions of nitrogen fixation is an important part of the lifestyle of strain BH72 in roots, as a wide range of genes far beyond the nif regulon is modulated. Moreover, the NifA regulon in strain BH72 appears to encompass a wider range of

Meta-analysis of 32 genome-wide linkage studies of schizophrenia

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Ng, MYM; Levinson, DF; Faraone, SV; Suarez, BK; DeLisi, LE; Arinami, T; Riley, B; Paunio, T; Pulver, AE; Irmansyah; Holmans, PA; Escamilla, M; Wildenauer, DB; Williams, NM; Laurent, C; Mowry, BJ; Brzustowicz, LM; Maziade, M; Sklar, P; Garver, DL; Abecasis, GR; Lerer, B; Fallin, MD; Gurling, HMD; Gejman, PV; Lindholm, E; Moises, HW; Byerley, W; Wijsman, EM; Forabosco, P; Tsuang, MT; Hwu, H-G; Okazaki, Y; Kendler, KS; Wormley, B; Fanous, A; Walsh, D; O’Neill, FA; Peltonen, L; Nestadt, G; Lasseter, VK; Liang, KY; Papadimitriou, GM; Dikeos, DG; Schwab, SG; Owen, MJ; O’Donovan, MC; Norton, N; Hare, E; Raventos, H; Nicolini, H; Albus, M; Maier, W; Nimgaonkar, VL; Terenius, L; Mallet, J; Jay, M; Godard, S; Nertney, D; Alexander, M; Crowe, RR; Silverman, JM; Bassett, AS; Roy, M-A; Mérette, C; Pato, CN; Pato, MT; Roos, J Louw; Kohn, Y; Amann-Zalcenstein, D; Kalsi, G; McQuillin, A; Curtis, D; Brynjolfson, J; Sigmundsson, T; Petursson, H; Sanders, AR; Duan, J; Jazin, E; Myles-Worsley, M; Karayiorgou, M; Lewis, CM

2009-01-01

A genome scan meta-analysis (GSMA) was carried out on 32 independent genome-wide linkage scan analyses that included 3255 pedigrees with 7413 genotyped cases affected with schizophrenia (SCZ) or related disorders. The primary GSMA divided the autosomes into 120 bins, rank-ordered the bins within each study according to the most positive linkage result in each bin, summed these ranks (weighted for study size) for each bin across studies and determined the empirical probability of a given summed rank (PSR) by simulation. Suggestive evidence for linkage was observed in two single bins, on chromosomes 5q (142-168 Mb) and 2q (103-134 Mb). Genome-wide evidence for linkage was detected on chromosome 2q (119-152 Mb) when bin boundaries were shifted to the middle of the previous bins. The primary analysis met empirical criteria for ‘aggregate’ genome-wide significance, indicating that some or all of 10 bins are likely to contain loci linked to SCZ, including regions of chromosomes 1, 2q, 3q, 4q, 5q, 8p and 10q. In a secondary analysis of 22 studies of European-ancestry samples, suggestive evidence for linkage was observed on chromosome 8p (16-33 Mb). Although the newer genome-wide association methodology has greater power to detect weak associations to single common DNA sequence variants, linkage analysis can detect diverse genetic effects that segregate in families, including multiple rare variants within one locus or several weakly associated loci in the same region. Therefore, the regions supported by this meta-analysis deserve close attention in future studies. PMID:19349958

Genome-wide association study in Finnish twins highlights the connection between nicotine addiction and neurotrophin signaling pathway.

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Hällfors, Jenni; Palviainen, Teemu; Surakka, Ida; Gupta, Richa; Buchwald, Jadwiga; Raevuori, Anu; Ripatti, Samuli; Korhonen, Tellervo; Jousilahti, Pekka; Madden, Pamela A F; Kaprio, Jaakko; Loukola, Anu

2018-03-13

The heritability of nicotine dependence based on family studies is substantial. Nevertheless, knowledge of the underlying genetic architecture remains meager. Our aim was to identify novel genetic variants responsible for interindividual differences in smoking behavior. We performed a genome-wide association study on 1715 ever smokers ascertained from the population-based Finnish Twin Cohort enriched for heavy smoking. Data imputation used the 1000 Genomes Phase I reference panel together with a whole genome sequence-based Finnish reference panel. We analyzed three measures of nicotine addiction-smoking quantity, nicotine dependence and nicotine withdrawal. We annotated all genome-wide significant SNPs for their functional potential. First, we detected genome-wide significant association on 16p12 with smoking quantity (P = 8.5 × 10 -9 ), near CLEC19A. The lead-SNP stands 22 kb from a binding site for NF-κB transcription factors, which play a role in the neurotrophin signaling pathway. However, the signal was not replicated in an independent Finnish population-based sample, FINRISK (n = 6763). Second, nicotine withdrawal showed association on 2q21 in an intron of TMEM163 (P = 2.1 × 10 -9 ), and on 11p15 (P = 6.6 × 10 -8 ) in an intron of AP2A2, and P = 4.2 × 10 -7 for a missense variant in MUC6, both involved in the neurotrophin signaling pathway). Third, association was detected on 3p22.3 for maximum number of cigarettes smoked per day (P = 3.1 × 10 -8 ) near STAC. Associating CLEC19A and TMEM163 SNPs were annotated to influence gene expression or methylation. The neurotrophin signaling pathway has previously been associated with smoking behavior. Our findings further support the role in nicotine addiction. © 2018 The Authors. Addiction Biology published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.

The genome-wide early temporal response of Saccharomyces cerevisiae to oxidative stress induced by cumene hydroperoxide.

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Wei Sha

Full Text Available Oxidative stress is a well-known biological process that occurs in all respiring cells and is involved in pathophysiological processes such as aging and apoptosis. Oxidative stress agents include peroxides such as hydrogen peroxide, cumene hydroperoxide, and linoleic acid hydroperoxide, the thiol oxidant diamide, and menadione, a generator of superoxide, amongst others. The present study analyzed the early temporal genome-wide transcriptional response of Saccharomyces cerevisiae to oxidative stress induced by the aromatic peroxide cumene hydroperoxide. The accurate dataset obtained, supported by the use of temporal controls, biological replicates and well controlled growth conditions, provided a detailed picture of the early dynamics of the process. We identified a set of genes previously not implicated in the oxidative stress response, including several transcriptional regulators showing a fast transient response, suggesting a coordinated process in the transcriptional reprogramming. We discuss the role of the glutathione, thioredoxin and reactive oxygen species-removing systems, the proteasome and the pentose phosphate pathway. A data-driven clustering of the expression patterns identified one specific cluster that mostly consisted of genes known to be regulated by the Yap1p and Skn7p transcription factors, emphasizing their mediator role in the transcriptional response to oxidants. Comparison of our results with data reported for hydrogen peroxide identified 664 genes that specifically respond to cumene hydroperoxide, suggesting distinct transcriptional responses to these two peroxides. Genes up-regulated only by cumene hydroperoxide are mainly related to the cell membrane and cell wall, and proteolysis process, while those down-regulated only by this aromatic peroxide are involved in mitochondrial function.

Genome-wide association study of Tourette Syndrome

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Scharf, Jeremiah M.; Yu, Dongmei; Mathews, Carol A.; Neale, Benjamin M.; Stewart, S. Evelyn; Fagerness, Jesen A; Evans, Patrick; Gamazon, Eric; Edlund, Christopher K.; Service, Susan; Tikhomirov, Anna; Osiecki, Lisa; Illmann, Cornelia; Pluzhnikov, Anna; Konkashbaev, Anuar; Davis, Lea K; Han, Buhm; Crane, Jacquelyn; Moorjani, Priya; Crenshaw, Andrew T.; Parkin, Melissa A.; Reus, Victor I.; Lowe, Thomas L.; Rangel-Lugo, Martha; Chouinard, Sylvain; Dion, Yves; Girard, Simon; Cath, Danielle C; Smit, Jan H; King, Robert A.; Fernandez, Thomas; Leckman, James F.; Kidd, Kenneth K.; Kidd, Judith R.; Pakstis, Andrew J.; State, Matthew; Herrera, Luis Diego; Romero, Roxana; Fournier, Eduardo; Sandor, Paul; Barr, Cathy L; Phan, Nam; Gross-Tsur, Varda; Benarroch, Fortu; Pollak, Yehuda; Budman, Cathy L.; Bruun, Ruth D.; Erenberg, Gerald; Naarden, Allan L; Lee, Paul C; Weiss, Nicholas; Kremeyer, Barbara; Berrío, Gabriel Bedoya; Campbell, Desmond; Silgado, Julio C. Cardona; Ochoa, William Cornejo; Restrepo, Sandra C. Mesa; Muller, Heike; Duarte, Ana V. Valencia; Lyon, Gholson J; Leppert, Mark; Morgan, Jubel; Weiss, Robert; Grados, Marco A.; Anderson, Kelley; Davarya, Sarah; Singer, Harvey; Walkup, John; Jankovic, Joseph; Tischfield, Jay A.; Heiman, Gary A.; Gilbert, Donald L.; Hoekstra, Pieter J.; Robertson, Mary M.; Kurlan, Roger; Liu, Chunyu; Gibbs, J. Raphael; Singleton, Andrew; Hardy, John; Strengman, Eric; Ophoff, Roel; Wagner, Michael; Moessner, Rainald; Mirel, Daniel B.; Posthuma, Danielle; Sabatti, Chiara; Eskin, Eleazar; Conti, David V.; Knowles, James A.; Ruiz-Linares, Andres; Rouleau, Guy A.; Purcell, Shaun; Heutink, Peter; Oostra, Ben A.; McMahon, William; Freimer, Nelson; Cox, Nancy J.; Pauls, David L.

2012-01-01

Tourette Syndrome (TS) is a developmental disorder that has one of the highest familial recurrence rates among neuropsychiatric diseases with complex inheritance. However, the identification of definitive TS susceptibility genes remains elusive. Here, we report the first genome-wide association study (GWAS) of TS in 1285 cases and 4964 ancestry-matched controls of European ancestry, including two European-derived population isolates, Ashkenazi Jews from North America and Israel, and French Canadians from Quebec, Canada. In a primary meta-analysis of GWAS data from these European ancestry samples, no markers achieved a genome-wide threshold of significance (p<5 × 10−8); the top signal was found in rs7868992 on chromosome 9q32 within COL27A1 (p=1.85 × 10−6). A secondary analysis including an additional 211 cases and 285 controls from two closely-related Latin-American population isolates from the Central Valley of Costa Rica and Antioquia, Colombia also identified rs7868992 as the top signal (p=3.6 × 10−7 for the combined sample of 1496 cases and 5249 controls following imputation with 1000 Genomes data). This study lays the groundwork for the eventual identification of common TS susceptibility variants in larger cohorts and helps to provide a more complete understanding of the full genetic architecture of this disorder. PMID:22889924

Genome-wide analysis of regions similar to promoters of histone genes

KAUST Repository

Chowdhary, Rajesh

2010-05-28

Background: The purpose of this study is to: i) develop a computational model of promoters of human histone-encoding genes (shortly histone genes), an important class of genes that participate in various critical cellular processes, ii) use the model so developed to identify regions across the human genome that have similar structure as promoters of histone genes; such regions could represent potential genomic regulatory regions, e.g. promoters, of genes that may be coregulated with histone genes, and iii/ identify in this way genes that have high likelihood of being coregulated with the histone genes.Results: We successfully developed a histone promoter model using a comprehensive collection of histone genes. Based on leave-one-out cross-validation test, the model produced good prediction accuracy (94.1% sensitivity, 92.6% specificity, and 92.8% positive predictive value). We used this model to predict across the genome a number of genes that shared similar promoter structures with the histone gene promoters. We thus hypothesize that these predicted genes could be coregulated with histone genes. This hypothesis matches well with the available gene expression, gene ontology, and pathways data. Jointly with promoters of the above-mentioned genes, we found a large number of intergenic regions with similar structure as histone promoters.Conclusions: This study represents one of the most comprehensive computational analyses conducted thus far on a genome-wide scale of promoters of human histone genes. Our analysis suggests a number of other human genes that share a high similarity of promoter structure with the histone genes and thus are highly likely to be coregulated, and consequently coexpressed, with the histone genes. We also found that there are a large number of intergenic regions across the genome with their structures similar to promoters of histone genes. These regions may be promoters of yet unidentified genes, or may represent remote control regions that

A Genome-Wide Methylation Study of Severe Vitamin D Deficiency in African American Adolescents

NARCIS (Netherlands)

Zhu, Haidong; Wang, Xiaoling; Shi, Huidong; Su, Shaoyong; Harshfield, Gregory A.; Gutin, Bernard; Snieder, Harold; Dong, Yanbin

Objectives To test the hypothesis that changes in DNA methylation are involved in vitamin D deficiency-related immune cell regulation using an unbiased genome-wide approach combined with a genomic and epigenomic integrative approach. Study design We performed a genome-wide methylation scan using the

Assembly of the Lactuca sativa, L. cv. Tizian draft genome sequence reveals differences within major resistance complex 1 as compared to the cv. Salinas reference genome.

Science.gov (United States)

Verwaaijen, Bart; Wibberg, Daniel; Nelkner, Johanna; Gordin, Miriam; Rupp, Oliver; Winkler, Anika; Bremges, Andreas; Blom, Jochen; Grosch, Rita; Pühler, Alfred; Schlüter, Andreas

2018-02-10

Lettuce (Lactuca sativa, L.) is an important annual plant of the family Asteraceae (Compositae). The commercial lettuce cultivar Tizian has been used in various scientific studies investigating the interaction of the plant with phytopathogens or biological control agents. Here, we present the de novo draft genome sequencing and gene prediction for this specific cultivar derived from transcriptome sequence data. The assembled scaffolds amount to a size of 2.22 Gb. Based on RNAseq data, 31,112 transcript isoforms were identified. Functional predictions for these transcripts were determined within the GenDBE annotation platform. Comparison with the cv. Salinas reference genome revealed a high degree of sequence similarity on genome and transcriptome levels, with an average amino acid identity of 99%. Furthermore, it was observed that two large regions are either missing or are highly divergent within the cv. Tizian genome compared to cv. Salinas. One of these regions covers the major resistance complex 1 region of cv. Salinas. The cv. Tizian draft genome sequence provides a valuable resource for future functional and transcriptome analyses focused on this lettuce cultivar. Copyright © 2017 Elsevier B.V. All rights reserved.