Expressed sequence tag analysis of adult human lens for the NEIBank Project: over 2000 non-redundant transcripts, novel genes and splice variants.

PubMed

Wistow, Graeme; Bernstein, Steven L; Wyatt, M Keith; Behal, Amita; Touchman, Jeffrey W; Bouffard, Gerald; Smith, Don; Peterson, Katherine

2002-06-15

To explore the expression profile of the human lens and to provide a resource for microarray studies, expressed sequence tag (EST) analysis has been performed on cDNA libraries from adult lenses. A cDNA library was constructed from two adult (40 year old) human lenses. Over two thousand clones were sequenced from the unamplified, un-normalized library. The library was then normalized and a further 2200 sequences were obtained. All the data were analyzed using GRIST (GRouping and Identification of Sequence Tags), a procedure for gene identification and clustering. The lens library (by) contains a low percentage of non-mRNA contaminants and a high fraction (over 75%) of apparently full length cDNA clones. Approximately 2000 reads from the unamplified library yields 810 clusters, potentially representing individual genes expressed in the lens. After normalization, the content of crystallins and other abundant cDNAs is markedly reduced and a similar number of reads from this library (fs) yields 1455 unique groups of which only two thirds correspond to named genes in GenBank. Among the most abundant cDNAs is one for a novel gene related to glutamine synthetase, which was designated "lengsin" (LGS). Analyses of ESTs also reveal examples of alternative transcripts, including a major alternative splice form for the lens specific membrane protein MP19. Variant forms for other transcripts, including those encoding the apoptosis inhibitor Livin and the armadillo repeat protein ARVCF, are also described. The lens cDNA libraries are a resource for gene discovery, full length cDNAs for functional studies and microarrays. The discovery of an abundant, novel transcript, lengsin, and a major novel splice form of MP19 reflect the utility of unamplified libraries constructed from dissected tissue. Many novel transcripts and splice forms are represented, some of which may be candidates for genetic diseases.

[Construction of forward and reverse subtracted cDNA libraries between muscle tissue of Meishan and Landrace pigs].

PubMed

Xu, De-Quan; Zhang, Yi-Bing; Xiong, Yuan-Zhu; Gui, Jian-Fang; Jiang, Si-Wen; Su, Yu-Hong

2003-07-01

Using suppression subtractive hybridization (SSH) technique, forward and reverse subtracted cDNA libraries were constructed between Longissimus muscles from Meishan and Landrace pigs. A housekeeping gene, G3PDH, was used to estimate the efficiency of subtractive cDNA. In two cDNA libraries, G3PDH was subtracted very efficiently at appropriate 2(10) and 2(5) folds, respectively, indicating that some differentially expressed genes were also enriched at the same folds and the two subtractive cDNA libraries were very successful. A total of 709 and 673 positive clones were isolated from forward and reverse subtracted cDNA libraries, respectively. Analysis of PCR showed that most of all plasmids in the clones contained 150-750 bp inserts. The construction of subtractive cDNA libraries between muscle tissue from different pig breeds laid solid foundations for isolating and identifying the genes determining muscle growth and meat quality, which will be important to understand the mechanism of muscle growth, determination of meat quality and practice of molecular breeding.

Balancing gene expression without library construction via a reusable sRNA pool.

PubMed

Ghodasara, Amar; Voigt, Christopher A

2017-07-27

Balancing protein expression is critical when optimizing genetic systems. Typically, this requires library construction to vary the genetic parts controlling each gene, which can be expensive and time-consuming. Here, we develop sRNAs corresponding to 15nt 'target' sequences that can be inserted upstream of a gene. The targeted gene can be repressed from 1.6- to 87-fold by controlling sRNA expression using promoters of different strength. A pool is built where six sRNAs are placed under the control of 16 promoters that span a ∼103-fold range of strengths, yielding ∼107 combinations. This pool can simultaneously optimize up to six genes in a system. This requires building only a single system-specific construct by placing a target sequence upstream of each gene and transforming it with the pre-built sRNA pool. The resulting library is screened and the top clone is sequenced to determine the promoter controlling each sRNA, from which the fold-repression of the genes can be inferred. The system is then rebuilt by rationally selecting parts that implement the optimal expression of each gene. We demonstrate the versatility of this approach by using the same pool to optimize a metabolic pathway (β-carotene) and genetic circuit (XNOR logic gate). © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Toward functional genomics in bacteria: Analysis of gene expression in Escherichia coli from a bacterial artificial chromosome library of Bacillus cereus

PubMed Central

Rondon, Michelle R.; Raffel, Sandra J.; Goodman, Robert M.; Handelsman, Jo

1999-01-01

As the study of microbes moves into the era of functional genomics, there is an increasing need for molecular tools for analysis of a wide diversity of microorganisms. Currently, biological study of many prokaryotes of agricultural, medical, and fundamental scientific interest is limited by the lack of adequate genetic tools. We report the application of the bacterial artificial chromosome (BAC) vector to prokaryotic biology as a powerful approach to address this need. We constructed a BAC library in Escherichia coli from genomic DNA of the Gram-positive bacterium Bacillus cereus. This library provides 5.75-fold coverage of the B. cereus genome, with an average insert size of 98 kb. To determine the extent of heterologous expression of B. cereus genes in the library, we screened it for expression of several B. cereus activities in the E. coli host. Clones expressing 6 of 10 activities tested were identified in the library, namely, ampicillin resistance, zwittermicin A resistance, esculin hydrolysis, hemolysis, orange pigment production, and lecithinase activity. We analyzed selected BAC clones genetically to identify rapidly specific B. cereus loci. These results suggest that BAC libraries will provide a powerful approach for studying gene expression from diverse prokaryotes. PMID:10339608

A part toolbox to tune genetic expression in Bacillus subtilis

PubMed Central

Guiziou, Sarah; Sauveplane, Vincent; Chang, Hung-Ju; Clerté, Caroline; Declerck, Nathalie; Jules, Matthieu; Bonnet, Jerome

2016-01-01

Libraries of well-characterised components regulating gene expression levels are essential to many synthetic biology applications. While widely available for the Gram-negative model bacterium Escherichia coli, such libraries are lacking for the Gram-positive model Bacillus subtilis, a key organism for basic research and biotechnological applications. Here, we engineered a genetic toolbox comprising libraries of promoters, Ribosome Binding Sites (RBS), and protein degradation tags to precisely tune gene expression in B. subtilis. We first designed a modular Expression Operating Unit (EOU) facilitating parts assembly and modifications and providing a standard genetic context for gene circuits implementation. We then selected native, constitutive promoters of B. subtilis and efficient RBS sequences from which we engineered three promoters and three RBS sequence libraries exhibiting ∼14 000-fold dynamic range in gene expression levels. We also designed a collection of SsrA proteolysis tags of variable strength. Finally, by using fluorescence fluctuation methods coupled with two-photon microscopy, we quantified the absolute concentration of GFP in a subset of strains from the library. Our complete promoters and RBS sequences library comprising over 135 constructs enables tuning of GFP concentration over five orders of magnitude, from 0.05 to 700 μM. This toolbox of regulatory components will support many research and engineering applications in B. subtilis. PMID:27402159

Formation of Nitrogenase NifDK Tetramers in the Mitochondria of Saccharomyces cerevisiae

PubMed Central

2017-01-01

Transferring the prokaryotic enzyme nitrogenase into a eukaryotic host with the final aim of developing N2 fixing cereal crops would revolutionize agricultural systems worldwide. Targeting it to mitochondria has potential advantages because of the organelle’s high O2 consumption and the presence of bacterial-type iron–sulfur cluster biosynthetic machinery. In this study, we constructed 96 strains of Saccharomyces cerevisiae in which transcriptional units comprising nine Azotobacter vinelandii nif genes (nifHDKUSMBEN) were integrated into the genome. Two combinatorial libraries of nif gene clusters were constructed: a library of mitochondrial leading sequences consisting of 24 clusters within four subsets of nif gene expression strength, and an expression library of 72 clusters with fixed mitochondrial leading sequences and nif expression levels assigned according to factorial design. In total, 29 promoters and 18 terminators were combined to adjust nif gene expression levels. Expression and mitochondrial targeting was confirmed at the protein level as immunoblot analysis showed that Nif proteins could be efficiently accumulated in mitochondria. NifDK tetramer formation, an essential step of nitrogenase assembly, was experimentally proven both in cell-free extracts and in purified NifDK preparations. This work represents a first step toward obtaining functional nitrogenase in the mitochondria of a eukaryotic cell. PMID:28221768

Synthetic Biology Toolbox for Controlling Gene Expression in the Cyanobacterium Synechococcus sp. strain PCC 7002

DOE Office of Scientific and Technical Information (OSTI.GOV)

Markley, Andrew L.; Begemann, Matthew B.; Clarke, Ryan E.

The application of synthetic biology requires characterized tools to precisely control gene expression. This toolbox of genetic parts previously did not exist for the industrially promising cyanobacterium, Synechococcus sp. strain PCC 7002. To address this gap, two orthogonal constitutive promoter libraries, one based on a cyanobacterial promoter and the other ported from Escherichia coli, were built and tested in PCC 7002. The libraries demonstrated 3 and 2.5 log dynamic ranges, respectively, but correlated poorly with E. coli expression levels. These promoter libraries were then combined to create and optimize a series of IPTG inducible cassettes. The resultant induction system hadmore » a 48-fold dynamic range and was shown to out-perform P trc constructs. Finally, a RBS library was designed and tested in PCC 7002. The presented synthetic biology toolbox will enable accelerated engineering of PCC 7002.« less

Synthetic Biology Toolbox for Controlling Gene Expression in the Cyanobacterium Synechococcus sp. strain PCC 7002

DOE PAGES

Markley, Andrew L.; Begemann, Matthew B.; Clarke, Ryan E.; ...

2014-09-12

The application of synthetic biology requires characterized tools to precisely control gene expression. This toolbox of genetic parts previously did not exist for the industrially promising cyanobacterium, Synechococcus sp. strain PCC 7002. To address this gap, two orthogonal constitutive promoter libraries, one based on a cyanobacterial promoter and the other ported from Escherichia coli, were built and tested in PCC 7002. The libraries demonstrated 3 and 2.5 log dynamic ranges, respectively, but correlated poorly with E. coli expression levels. These promoter libraries were then combined to create and optimize a series of IPTG inducible cassettes. The resultant induction system hadmore » a 48-fold dynamic range and was shown to out-perform P trc constructs. Finally, a RBS library was designed and tested in PCC 7002. The presented synthetic biology toolbox will enable accelerated engineering of PCC 7002.« less

High-throughput and reliable protocols for animal microRNA library cloning.

PubMed

Xiao, Caide

2011-01-01

MicroRNAs are short single-stranded RNA molecules (18-25 nucleotides). Because of their ability to silence gene expressions, they can be used to diagnose and treat tumors. Experimental construction of microRNA libraries was the most important step to identify microRNAs from animal tissues. Although there are many commercial kits with special protocols to construct microRNA libraries, this chapter provides the most reliable, high-throughput, and affordable protocols for microRNA library construction. The high-throughput capability of our protocols came from a double concentration (3 and 15%, thickness 1.5 mm) polyacrylamide gel electrophoresis (PAGE), which could directly extract microRNA-size RNAs from up to 400 μg total RNA (enough for two microRNA libraries). The reliability of our protocols was assured by a third PAGE, which selected PCR products of microRNA-size RNAs ligated with 5' and 3' linkers by a miRCat™ kit. Also, a MathCAD program was provided to automatically search short RNAs inserted between 5' and 3' linkers from thousands of sequencing text files.

A new method for the construction of a mutant library with a predictable occurrence rate using Poisson distribution.

PubMed

Seong, Ki Moon; Park, Hweon; Kim, Seong Jung; Ha, Hyo Nam; Lee, Jae Yung; Kim, Joon

2007-06-01

A yeast transcriptional activator, Gcn4p, induces the expression of genes that are involved in amino acid and purine biosynthetic pathways under amino acid starvation. Gcn4p has an acidic activation domain in the central region and a bZIP domain in the C-terminus that is divided into the DNA-binding motif and dimerization leucine zipper motif. In order to identify amino acids in the DNA-binding motif of Gcn4p which are involved in transcriptional activation, we constructed mutant libraries in the DNA-binding motif through an innovative application of random mutagenesis. Mutant library made by oligonucleotides which were mutated randomly using the Poisson distribution showed that the actual mutation frequency was in good agreement with expected values. This method could save the time and effort to create a mutant library with a predictable mutation frequency. Based on the studies using the mutant libraries constructed by the new method, the specific residues of the DNA-binding domain in Gcn4p appear to be involved in the transcriptional activities on a conserved binding site.

Secretory Overexpression of Bacillus thermocatenulatus Lipase in Saccharomyces cerevisiae Using Combinatorial Library Strategy.

PubMed

Kajiwara, Shota; Yamada, Ryosuke; Ogino, Hiroyasu

2018-04-10

Simple and cost-effective lipase expression host microorganisms are highly desirable. A combinatorial library strategy is used to improve the secretory expression of lipase from Bacillus thermocatenulatus (BTL2) in the culture supernatant of Saccharomyces cerevisiae. A plasmid library including expression cassettes composed of sequences encoding one of each 15 promoters, 15 secretion signals, and 15 terminators derived from yeast species, S. cerevisiae, Pichia pastoris, and Hansenula polymorpha, is constructed. The S. cerevisiae transformant YPH499/D4, comprising H. polymorpha GAP promoter, S. cerevisiae SAG1 secretion signal, and P. pastoris AOX1 terminator, is selected by high-throughput screening. This transformant expresses BTL2 extra-cellularly with a 130-fold higher than the control strain, comprising S. cerevisiae PGK1 promoter, S. cerevisiae α-factor secretion signal, and S. cerevisiae PGK1 terminator, after cultivation for 72 h. This combinatorial library strategy holds promising potential for application in the optimization of the secretory expression of proteins in yeast. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Analysis of expressed sequence tags from the four main developmental stages of Trypanosoma congolense

PubMed Central

Helm, Jared R.; Hertz-Fowler, Christiane; Aslett, Martin; Berriman, Matthew; Sanders, Mandy; Quail, Michael A.; Soares, Marcelo B.; Bonaldo, Maria F.; Sakurai, Tatsuya; Inoue, Noboru; Donelson, John E.

2009-01-01

Trypanosoma congolense is one of the most economically important pathogens of livestock in Africa. Culture-derived parasites of each of the three main insect stages of the T. congolense life cycle, i.e., the procyclic, epimastigote and metacyclic stages, and bloodstream stage parasites isolated from infected mice, were used to construct stage-specific cDNA libraries and expressed sequence tags (ESTs or cDNA clones) in each library were sequenced. Thirteen EST clusters encoding different variant surface glycoproteins (VSGs) were detected in the metacyclic library and twenty-six VSG EST clusters were found in the bloodstream library, six of which are shared by the metacyclic library. Rare VSG ESTs are present in the epimastigote library, and none were detected in the procyclic library. ESTs encoding enzymes that catalyze oxidative phosphorylation and amino acid metabolism are about twice as abundant in the procyclic and epimastigote stages as in the metacyclic and bloodstream stages. In contrast, ESTs encoding enzymes involved in glycolysis, the citric acid cycle and nucleotide metabolism are about the same in all four developmental stages. Cysteine proteases, kinases and phosphatases are the most abundant enzyme groups represented by the ESTs. All four libraries contain T. congolense-specific expressed sequences not present in the T. brucei and T. cruzi genomes. Normalized cDNA libraries were constructed from the metacyclic and bloodstream stages, and found to be further enriched for T. congolense-specific ESTs. Given that cultured T. congolense offers an experimental advantage over other African trypanosome species, these ESTs provide a basis for further investigation of the molecular properties of these four developmental stages, especially the epimastigote and metacyclic stages for which it is difficult to obtain large quantities of organisms. The T. congolense EST databases are available at: http://www.sanger.ac.uk/Projects/T_congolense/EST_index.shtml. PMID:19559733

Genome-Wide Tuning of Protein Expression Levels to Rapidly Engineer Microbial Traits.

PubMed

Freed, Emily F; Winkler, James D; Weiss, Sophie J; Garst, Andrew D; Mutalik, Vivek K; Arkin, Adam P; Knight, Rob; Gill, Ryan T

2015-11-20

The reliable engineering of biological systems requires quantitative mapping of predictable and context-independent expression over a broad range of protein expression levels. However, current techniques for modifying expression levels are cumbersome and are not amenable to high-throughput approaches. Here we present major improvements to current techniques through the design and construction of E. coli genome-wide libraries using synthetic DNA cassettes that can tune expression over a ∼10(4) range. The cassettes also contain molecular barcodes that are optimized for next-generation sequencing, enabling rapid and quantitative tracking of alleles that have the highest fitness advantage. We show these libraries can be used to determine which genes and expression levels confer greater fitness to E. coli under different growth conditions.

Construction and application of EST library from Setaria italica in response to dehydration stress.

PubMed

Zhang, Jinpeng; Liu, Tingsong; Fu, Junjie; Zhu, Yun; Jia, Jinping; Zheng, Jun; Zhao, Yinhe; Zhang, Ying; Wang, Guoying

2007-07-01

Foxtail millet is a gramineous crop with low water requirement. Despite its high water use efficiency, less attention has been paid to the molecular genetics of foxtail millet. This article reports the construction of subtracted cDNA libraries from foxtail millet seedlings under dehydration stress and the expression profile analysis of 1947 UniESTs from the subtracted cDNA libraries by a cDNA microarray. The results showed that 95 and 57 ESTs were upregulated by dehydration stress, respectively, in roots and shoots of seedlings and that 10 and 27 ESTs were downregulated, respectively, in roots and shoots. The expression profile analysis showed that genes induced in foxtail millet roots were different from those in shoots during dehydration stress and that the early response to dehydration stress in foxtail millet roots was the activation of the glycolysis metabolism. Moreover, protein degradation pathway may also play a pivotal role in drought-tolerant responses of foxtail millet. Finally, Northern blot analysis validated well the cDNA microarray data.

Writing DNA with GenoCAD.

PubMed

Czar, Michael J; Cai, Yizhi; Peccoud, Jean

2009-07-01

Chemical synthesis of custom DNA made to order calls for software streamlining the design of synthetic DNA sequences. GenoCAD (www.genocad.org) is a free web-based application to design protein expression vectors, artificial gene networks and other genetic constructs composed of multiple functional blocks called genetic parts. By capturing design strategies in grammatical models of DNA sequences, GenoCAD guides the user through the design process. By successively clicking on icons representing structural features or actual genetic parts, complex constructs composed of dozens of functional blocks can be designed in a matter of minutes. GenoCAD automatically derives the construct sequence from its comprehensive libraries of genetic parts. Upon completion of the design process, users can download the sequence for synthesis or further analysis. Users who elect to create a personal account on the system can customize their workspace by creating their own parts libraries, adding new parts to the libraries, or reusing designs to quickly generate sets of related constructs.

A transposase strategy for creating libraries of circularly permuted proteins.

PubMed

Mehta, Manan M; Liu, Shirley; Silberg, Jonathan J

2012-05-01

A simple approach for creating libraries of circularly permuted proteins is described that is called PERMutation Using Transposase Engineering (PERMUTE). In PERMUTE, the transposase MuA is used to randomly insert a minitransposon that can function as a protein expression vector into a plasmid that contains the open reading frame (ORF) being permuted. A library of vectors that express different permuted variants of the ORF-encoded protein is created by: (i) using bacteria to select for target vectors that acquire an integrated minitransposon; (ii) excising the ensemble of ORFs that contain an integrated minitransposon from the selected vectors; and (iii) circularizing the ensemble of ORFs containing integrated minitransposons using intramolecular ligation. Construction of a Thermotoga neapolitana adenylate kinase (AK) library using PERMUTE revealed that this approach produces vectors that express circularly permuted proteins with distinct sequence diversity from existing methods. In addition, selection of this library for variants that complement the growth of Escherichia coli with a temperature-sensitive AK identified functional proteins with novel architectures, suggesting that PERMUTE will be useful for the directed evolution of proteins with new functions.

A transposase strategy for creating libraries of circularly permuted proteins

PubMed Central

Mehta, Manan M.; Liu, Shirley; Silberg, Jonathan J.

2012-01-01

A simple approach for creating libraries of circularly permuted proteins is described that is called PERMutation Using Transposase Engineering (PERMUTE). In PERMUTE, the transposase MuA is used to randomly insert a minitransposon that can function as a protein expression vector into a plasmid that contains the open reading frame (ORF) being permuted. A library of vectors that express different permuted variants of the ORF-encoded protein is created by: (i) using bacteria to select for target vectors that acquire an integrated minitransposon; (ii) excising the ensemble of ORFs that contain an integrated minitransposon from the selected vectors; and (iii) circularizing the ensemble of ORFs containing integrated minitransposons using intramolecular ligation. Construction of a Thermotoga neapolitana adenylate kinase (AK) library using PERMUTE revealed that this approach produces vectors that express circularly permuted proteins with distinct sequence diversity from existing methods. In addition, selection of this library for variants that complement the growth of Escherichia coli with a temperature-sensitive AK identified functional proteins with novel architectures, suggesting that PERMUTE will be useful for the directed evolution of proteins with new functions. PMID:22319214

Generation of a total of 6483 expressed sequence tags from 60 day-old bovine whole fetus and fetal placenta.

PubMed

Oishi, M; Gohma, H; Lejukole, H Y; Taniguchi, Y; Yamada, T; Suzuki, K; Shinkai, H; Uenishi, H; Yasue, H; Sasaki, Y

2004-05-01

Expressed sequence tags (ESTs) generated based on characterization of clones isolated randomly from cDNA libraries are used to study gene expression profiles in specific tissues and to provide useful information for characterizing tissue physiology. In this study, two directionally cloned cDNA libraries were constructed from 60 day-old bovine whole fetus and fetal placenta. We have characterized 5357 and 1126 clones, and then identified 3464 and 795 unique sequences for the fetus and placenta cDNA libraries: 1851 and 504 showed homology to already identified genes, and 1613 and 291 showed no significant matches to any of the sequences in DNA databases, respectively. Further, we found 94 unique sequences overlapping in both the fetus and the placenta, leading to a catalog of 4165 genes expressed in 60 day-old fetus and placenta. The catalog is used to examine expression profile of genes in 60 day-old bovine fetus and placenta.

SAGE analysis of early oogenesis in the silkworm, Bombyx mori.

PubMed

Funaguma, Shunsuke; Hashimoto, Shin-ichi; Suzuki, Yutaka; Omuro, Naoko; Sugano, Sumio; Mita, Kazuei; Katsuma, Susumu; Shimada, Toru

2007-02-01

To identify genes involved in the differentiation of Bombyx cystoblast, we constructed two 3' long serial analysis of gene expression (Long SAGE) libraries from stage 1-3 or stage 2-3 egg chambers and compared their gene expression profiles. In both libraries, the most frequent tags were derived from the same novel transcript. The transcript does not have any open reading frame capable of encoding a protein with over 100 amino acids in length. RNA blot analysis revealed that this transcript is specifically and abundantly expressed in the Bombyx ovary, mainly the germ line cells in the ovarioles. These results suggest that Bombyx oogenesis may be regulated by a previously unidentified non-coding RNA. Comparison of the gene expression profiles between the stage 1-3 and stage 2-3 egg chamber libraries revealed that 272 tags were significantly more abundant in stage 1-3 egg chambers (p<0.05 and at least two-fold change) than in library 2. Among the differentially expressed transcripts were the sequences that correspond to ATP synthase subunit d (3.1-fold enriched) and ATP synthase coupling factor 6 (9.1-fold enriched), suggesting that they are involved in regulation of cell cycle of cystocytes.

A genome-wide inducible phenotypic screen identifies antisense RNA constructs silencing Escherichia coli essential genes

PubMed Central

Meng, Jia; Kanzaki, Gregory; Meas, Diane; Lam, Christopher K.; Crummer, Heather; Tain, Justina; Xu, H. Howard

2013-01-01

Regulated antisense RNA (asRNA) expression has been employed successfully in Gram-positive bacteria for genome-wide essential gene identification and drug target determination. However, there have been no published reports describing the application of asRNA gene silencing for comprehensive analyses of essential genes in Gram-negative bacteria. In this study, we report the first genome-wide identification of asRNA constructs for essential genes in Escherichia coli. We screened 250,000 library transformants for conditional growth-inhibitory recombinant clones from two shot-gun genomic libraries of E. coli using a paired-termini expression vector (pHN678). After sequencing plasmid inserts of 675 confirmed inducer-sensitive cell clones, we identified 152 separate asRNA constructs of which 134 inserts came from essential genes while 18 originated from non-essential genes (but share operons with essential genes). Among the 79 individual essential genes silenced by these asRNA constructs, 61 genes (77%) engage in processes related to protein synthesis. The cell-based assays of an asRNA clone targeting fusA (encoding elongation factor G) showed that the induced cells were sensitized 12 fold to fusidic acid, a known specific inhibitor. Our results demonstrate the utility of the paired-termini expression vector and feasibility of large-scale gene silencing in E. coli using regulated asRNA expression. PMID:22268863

Exploitation of rolling circle amplification for the construction of large phage-display antibody libraries.

PubMed

Shahsavarian, Melody A; Le Minoux, Damien; Matti, Kalyankumar M; Kaveri, Srini; Lacroix-Desmazes, Sébastien; Boquet, Didier; Friboulet, Alain; Avalle, Bérangère; Padiolleau-Lefèvre, Séverine

2014-05-01

Phage display antibody libraries have proven to have a significant role in the discovery of therapeutic antibodies and polypeptides with desired biological and physicochemical properties. Obtaining a large and diverse phage display antibody library, however, is always a challenging task. Various steps of this technique can still undergo optimization in order to obtain an efficient library. In the construction of a single chain fragment variable (scFv) phage display library, the cloning of the scFv fragments into a phagemid vector is of crucial importance. An efficient restriction enzyme digestion of the scFv DNA leads to its proper ligation with the phagemid followed by its successful cloning and expression. Here, we are reporting a different approach to enhance the efficiency of the restriction enzyme digestion step. We have exploited rolling circle amplification (RCA) to produce a long strand of DNA with tandem repeats of scFv sequences, which is found to be highly susceptible to restriction digestion. With this important modification, we are able to construct a large phage display antibody library of naive SJL/J mice. The size of the library is estimated as ~10(8) clones. The number of clones containing a scFv fragment is estimated at 90%. Hence, the present results could considerably aid the utilization of the phage-display technique in order to get an efficiently large antibody library. Copyright © 2014 Elsevier B.V. All rights reserved.

Differential cDNA cloning by enzymatic degrading subtraction (EDS).

PubMed Central

Zeng, J; Gorski, R A; Hamer, D

1994-01-01

We describe a new method, called enzymatic degrading subtraction (EDS), for the construction of subtractive libraries from PCR amplified cDNA. The novel features of this method are that i) the tester DNA is blocked by thionucleotide incorporation; ii) the rate of hybridization is accelerated by phenol-emulsion reassociation; and iii) the driver cDNA and hybrid molecules are enzymatically removed by digestion with exonucleases III and VII rather than by physical partitioning. We demonstrate the utility of EDS by constructing a subtractive library enriched for cDNAs expressed in adult but not in embryonic rat brains. Images PMID:7971268

Dominant genetics using a yeast genomic library under the control of a strong inducible promoter.

PubMed

Ramer, S W; Elledge, S J; Davis, R W

1992-12-01

In Saccharomyces cerevisiae, numerous genes have been identified by selection from high-copy-number libraries based on "multicopy suppression" or other phenotypic consequences of overexpression. Although fruitful, this approach suffers from two major drawbacks. First, high copy number alone may not permit high-level expression of tightly regulated genes. Conversely, other genes expressed in proportion to dosage cannot be identified if their products are toxic at elevated levels. This work reports construction of a genomic DNA expression library for S. cerevisiae that circumvents both limitations by fusing randomly sheared genomic DNA to the strong, inducible yeast GAL1 promoter, which can be regulated by carbon source. The library obtained contains 5 x 10(7) independent recombinants, representing a breakpoint at every base in the yeast genome. This library was used to examine aberrant gene expression in S. cerevisiae. A screen for dominant activators of yeast mating response identified eight genes that activate the pathway in the absence of exogenous mating pheromone, including one previously unidentified gene. One activator was a truncated STE11 gene lacking approximately 1000 base pairs of amino-terminal coding sequence. In two different clones, the same GAL1 promoter-proximal ATG is in-frame with the coding sequence of STE11, suggesting that internal initiation of translation there results in production of a biologically active, truncated STE11 protein. Thus this library allows isolation based on dominant phenotypes of genes that might have been difficult or impossible to isolate from high-copy-number libraries.

An anti-tumor protein produced by Trichinella spiralis and identified by screening a T7 phage display library, induces apoptosis in human hepatoma H7402 cells

USDA-ARS?s Scientific Manuscript database

Trichinella spiralis infection confers effective resistance to tumor cell expansion. In this study, a T7 phage cDNA display library was constructed to express genes encoded by T. spiralis. Organic phase multi-cell screening was used to sort through candidate proteins in a transfected human chronic m...

Construction of cDNA expression library of watermelon for isolation of ClWRKY1 transcription factors gene involved in resistance to Fusarium wilt.

PubMed

Yang, Bing-Yan; Huo, Xiu-Ai; Li, Peng-Fei; Wang, Cui-Xia; Duan, Hui-Jun

2014-08-01

Full-length cDNAs are very important for genome annotation and functional analysis of genes. The number of full-length cDNAs from watermelon remains limited. Here we report first the construction of a full-length enriched cDNA library from Fusarium wilt stressed watermelon (Citrullus lanatus Thunb.) cultivar PI296341 root tissues using the SMART method. The titer of primary cDNA library and amplified library was 2.21 x 10(6) and 2.0 x 10(10) pfu/ml, respectively and the rate of recombinant was above 85%. The size of insert fragment ranged from 0.3 to 2.0 kb. In this study, we first cloned a gene named ClWRKY1, which was 1981 bp long and encoded a protein consisting of 394 amino acids. It contained two characteristic WRKY domains and two zinc finger motifs. Quantitative real-time PCR showed that ClWRKY1 expression levels reached maximum level at 12 h after inoculation with Fusarium oxysporum f. sp. niveum. The full-length cDNA library of watermelon root tissues is not only essential for the cloning of genes which are known, but also an initial key for the screening and cloning of new genes that might be involved in resistance to Fusarium wilt.

Genome-Wide Analysis of Differentially Expressed Genes Relevant to Rhizome Formation in Lotus Root (Nelumbo nucifera Gaertn)

PubMed Central

Yin, Jingjing; Li, Liangjun; Chen, Xuehao

2013-01-01

Lotus root is a popular wetland vegetable which produces edible rhizome. At the molecular level, the regulation of rhizome formation is very complex, which has not been sufficiently addressed in research. In this study, to identify differentially expressed genes (DEGs) in lotus root, four libraries (L1 library: stolon stage, L2 library: initial swelling stage, L3 library: middle swelling stage, L4: later swelling stage) were constructed from the rhizome development stages. High-throughput tag-sequencing technique was used which is based on Solexa Genome Analyzer Platform. Approximately 5.0 million tags were sequenced, and 4542104, 4474755, 4777919, and 4750348 clean tags including 151282, 137476, 215872, and 166005 distinct tags were obtained after removal of low quality tags from each library respectively. More than 43% distinct tags were unambiguous tags mapping to the reference genes, and 40% were unambiguous tag-mapped genes. From L1, L2, L3, and L4, total 20471, 18785, 23448, and 21778 genes were annotated, after mapping their functions in existing databases. Profiling of gene expression in L1/L2, L2/L3, and L3/L4 libraries were different among most of the selected 20 DEGs. Most of the DEGs in L1/L2 libraries were relevant to fiber development and stress response, while in L2/L3 and L3/L4 libraries, major of the DEGs were involved in metabolism of energy and storage. All up-regulated transcriptional factors in four libraries and 14 important rhizome formation-related genes in four libraries were also identified. In addition, the expression of 9 genes from identified DEGs was performed by qRT-PCR method. In a summary, this study provides a comprehensive understanding of gene expression during the rhizome formation in lotus root. PMID:23840598

Combinatorial Screening for Transgenic Yeasts with High Cellulase Activities in Combination with a Tunable Expression System

PubMed Central

Ito, Yoichiro; Yamanishi, Mamoru; Ikeuchi, Akinori; Imamura, Chie; Matsuyama, Takashi

2015-01-01

Combinatorial screening used together with a broad library of gene expression cassettes is expected to produce a powerful tool for the optimization of the simultaneous expression of multiple enzymes. Recently, we proposed a highly tunable protein expression system that utilized multiple genome-integrated target genes to fine-tune enzyme expression in yeast cells. This tunable system included a library of expression cassettes each composed of three gene-expression control elements that in different combinations produced a wide range of protein expression levels. In this study, four gene expression cassettes with graded protein expression levels were applied to the expression of three cellulases: cellobiohydrolase 1, cellobiohydrolase 2, and endoglucanase 2. After combinatorial screening for transgenic yeasts simultaneously secreting these three cellulases, we obtained strains with higher cellulase expressions than a strain harboring three cellulase-expression constructs within one high-performance gene expression cassette. These results show that our method will be of broad use throughout the field of metabolic engineering. PMID:26692026

Paramyosin from the parasitic mite Sarcoptes scabiei: cDNA cloning and heterologous expression.

PubMed

Mattsson, J G; Ljunggren, E L; Bergström, K

2001-05-01

The burrowing mite Sarcoptes scabiei is the causative agent of the highly contagious disease sarcoptic mange or scabies. So far, there is no in vitro propagation system for S. scabiei available, and mites used for various purposes must be isolated from infected hosts. Lack of parasite-derived material has limited the possibilities to study several aspects of scabies, including pathogenesis and immunity. It has also hampered the development of high performance serological assays. We have now constructed an S. scabiei cDNA expression library with mRNA purified from mites isolated from red foxes. Immunoscreening of the library enabled us to clone a full-length cDNA coding for a 102.5 kDa protein. Sequence similarity searches identified the protein as a paramyosin. Recombinant S. scabiei paramyosin expressed in Escherichia coli was recognized by sera from dogs and swine infected with S. scabiei. We also designed a small paramyosin construct of about 17 kDa that included the N-terminal part, an evolutionary variable part of the helical core, and the C-terminal part of the molecule. The miniaturized protein was efficiently expressed in E. coli and was recognized by sera from immunized rabbits. These data demonstrate that the cDNA library can assist in the isolation of important S. scabiei antigens and that recombinant proteins can be useful for the study of scabies.

Harvesting of novel polyhydroxyalkanaote (PHA) synthase encoding genes from a soil metagenome library using phenotypic screening.

PubMed

Schallmey, Marcus; Ly, Anh; Wang, Chunxia; Meglei, Gabriela; Voget, Sonja; Streit, Wolfgang R; Driscoll, Brian T; Charles, Trevor C

2011-08-01

We previously reported the construction of metagenomic libraries in the IncP cosmid vector pRK7813, enabling heterologous expression of these broad-host-range libraries in multiple bacterial hosts. Expressing these libraries in Sinorhizobium meliloti, we have successfully complemented associated phenotypes of polyhydroxyalkanoate synthesis mutants. DNA sequence analysis of three clones indicates that the complementing genes are homologous to, but substantially different from, known polyhydroxyalkanaote synthase-encoding genes. Thus we have demonstrated the ability to isolate diverse genes for polyhydroxyalkanaote synthesis by functional complementation of defined mutants. Such genes might be of use in the engineering of more efficient systems for the industrial production of bioplastics. The use of functional complementation will also provide a vehicle to probe the genetics of polyhydroxyalkanaote metabolism and its relation to carbon availability in complex microbial assemblages. 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

A database of expressed genes from the new world screwworm, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae)

USDA-ARS?s Scientific Manuscript database

We used an expressed sequence tag and 454 pyrosequencing approach to initiate a study of the genome of the New World Screwworm, Cochliomyia hominivorax (Coquerel). Two normalized cDNA libraries were constructed from RNA isolated from embryos and 2nd instar larvae from the Panama 95 strain. Approxima...

Cloning of a Gene Whose Expression is Increased in Scrapie and in Senile Plaques in Human Brain

NASA Astrophysics Data System (ADS)

Wietgrefe, S.; Zupancic, M.; Haase, A.; Chesebro, B.; Race, R.; Frey, W.; Rustan, T.; Friedman, R. L.

1985-12-01

A complementary DNA library was constructed from messenger RNA's extracted from the brains of mice infected with the scrapie agent. The library was differentially screened with the objectives of finding clones that might be used as markers of infection and finding clones of genes whose increased expression might be correlated with the pathological changes common to scrapie and Alzheimer's disease. A gene was identified whose expression is increased in scrapie. The complementary DNA corresponding to this gene hybridized preferentially and focally to cells in the brains of scrapie-infected animals. The cloned DNA also hybridized to the neuritic plaques found with increased frequency in brains of patients with Alzheimer's disease.

Construction of a cDNA library for sea cucumber Acaudina leucoprocta and differential expression of ferritin peptide

NASA Astrophysics Data System (ADS)

Zhou, Jun; Hou, Fujing; Li, Ye; Su, Xiurong; Li, Taiwu; Jin, Chunhua

2016-07-01

Acaudina leucoprocta is an edible sea cucumber of economic interest that is widely distributed in China. Little information is available concerning the molecular genetics of this species although such knowledge would contribute to a better understanding of the optimal conditions for its aquaculture and its mechanisms of defense against disease. Therefore, we constructed a cDNA library and, based on bioinformatics analysis of the sequences, the functions of 75% of the cDNAs were identified, including those involved in cell structure, energy metabolism, mitochondrial function, and signal transduction pathways. Approximately 25% of genes in the library were unmatched. The gene for A. leucoprocta ferritin was also cloned. The predicted amino-acid sequence of ferritin displayed significant homology with other sea-cucumber counterparts but indicated that it was a new member of the ferritin family. Semiquantitative real-time RT-PCR indicated the highest levels of ferritin mRNA expression in the intestine. A polyclonal antibody of ferritin was also produced. These data provide a set of molecular tools essential for further studies of the functions of ferritin protein in A. leucoprocta.

Identification and functional analysis of a new glyphosate resistance gene from a fungus cDNA library.

PubMed

Tao, Bo; Shao, Bai-Hui; Qiao, Yu-Xin; Wang, Xiao-Qin; Chang, Shu-Jun; Qiu, Li-Juan

2017-08-01

Glyphosate is a widely used broad spectrum herbicide; however, this limits its use once crops are planted. If glyphosate-resistant crops are grown, glyphosate can be used for weed control in crops. While several glyphosate resistance genes are used in commercial glyphosate tolerant crops, there is interest in identifying additional genes for glyphosate tolerance. This research constructed a high-quality cDNA library form the glyphosate-resistant fungus Aspergillus oryzae RIB40 to identify genes that may confer resistance to glyphosate. Using a medium containing glyphosate (120mM), we screened several clones from the library. Based on a nucleotide sequence analysis, we identified a gene of unknown function (GenBank accession number: XM_001826835.2) that encoded a hypothetical 344-amino acid protein. The gene was named MFS40. Its ORF was amplified to construct an expression vector, pGEX-4T-1-MFS40, to express the protein in Escherichia coli BL21. The gene conferred glyphosate tolerance to E. coli ER2799 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Generation and analysis of the improved human HAL9/10 antibody phage display libraries.

PubMed

Kügler, Jonas; Wilke, Sonja; Meier, Doris; Tomszak, Florian; Frenzel, André; Schirrmann, Thomas; Dübel, Stefan; Garritsen, Henk; Hock, Björn; Toleikis, Lars; Schütte, Mark; Hust, Michael

2015-02-19

Antibody phage display is a proven key technology that allows the generation of human antibodies for diagnostics and therapy. From naive antibody gene libraries - in theory - antibodies against any target can be selected. Here we describe the design, construction and characterization of an optimized antibody phage display library. The naive antibody gene libraries HAL9 and HAL10, with a combined theoretical diversity of 1.5×10(10) independent clones, were constructed from 98 healthy donors using improved phage display vectors. In detail, most common phagemids employed for antibody phage display are using a combined His/Myc tag for detection and purification. We show that changing the tag order to Myc/His improved the production of soluble antibodies, but did not affect antibody phage display. For several published antibody libraries, the selected number of kappa scFvs were lower compared to lambda scFvs, probably due to a lower kappa scFv or Fab expression rate. Deletion of a phenylalanine at the end of the CL linker sequence in our new phagemid design increased scFv production rate and frequency of selected kappa antibodies significantly. The HAL libraries and 834 antibodies selected against 121 targets were analyzed regarding the used germline V-genes, used V-gene combinations and CDR-H3/-L3 length and composition. The amino acid diversity and distribution in the CDR-H3 of the initial library was retrieved in the CDR-H3 of selected antibodies showing that all CDR-H3 amino acids occurring in the human antibody repertoire can be functionally used and is not biased by E. coli expression or phage selection. Further, the data underline the importance of CDR length variations. The highly diverse universal antibody gene libraries HAL9/10 were constructed using an optimized scFv phagemid vector design. Analysis of selected antibodies revealed that the complete amino acid diversity in the CDR-H3 was also found in selected scFvs showing the functionality of the naive CDR-H3 diversity.

Construction and EST sequencing of full-length, drought stress cDNA libraries for common beans (Phaseolus vulgaris L.)

PubMed Central

2011-01-01

Background Common bean is an important legume crop with only a moderate number of short expressed sequence tags (ESTs) made with traditional methods. The goal of this research was to use full-length cDNA technology to develop ESTs that would overlap with the beginning of open reading frames and therefore be useful for gene annotation of genomic sequences. The library was also constructed to represent genes expressed under drought, low soil phosphorus and high soil aluminum toxicity. We also undertook comparisons of the full-length cDNA library to two previous non-full clone EST sets for common bean. Results Two full-length cDNA libraries were constructed: one for the drought tolerant Mesoamerican genotype BAT477 and the other one for the acid-soil tolerant Andean genotype G19833 which has been selected for genome sequencing. Plants were grown in three soil types using deep rooting cylinders subjected to drought and non-drought stress and tissues were collected from both roots and above ground parts. A total of 20,000 clones were selected robotically, half from each library. Then, nearly 10,000 clones from the G19833 library were sequenced with an average read length of 850 nucleotides. A total of 4,219 unigenes were identified consisting of 2,981 contigs and 1,238 singletons. These were functionally annotated with gene ontology terms and placed into KEGG pathways. Compared to other EST sequencing efforts in common bean, about half of the sequences were novel or represented the 5' ends of known genes. Conclusions The present full-length cDNA libraries add to the technological toolbox available for common bean and our sequencing of these clones substantially increases the number of unique EST sequences available for the common bean genome. All of this should be useful for both functional gene annotation, analysis of splice site variants and intron/exon boundary determination by comparison to soybean genes or with common bean whole-genome sequences. In addition the library has a large number of transcription factors and will be interesting for discovery and validation of drought or abiotic stress related genes in common bean. PMID:22118559

Developing a Synthetic Biology Toolkit for Comamonas testosteroni, an Emerging Cellular Chassis for Bioremediation.

PubMed

Tang, Qiang; Lu, Ting; Liu, Shuang-Jiang

2018-06-12

Synthetic biology is rapidly evolving into a new phase that emphasizes real-world applications such as environmental remediation. Recently, Comamonas testosteroni has become a promising chassis for bioremediation due to its natural pollutant-degrading capacity; however, its application is hindered by the lack of fundamental gene expression tools. Here, we present a synthetic biology toolkit that enables rapid creation of functional gene circuits in C. testosteroni. We first built a shuttle system that allows efficient circuit construction in E. coli and necessary phenotypic testing in C. testosteroni. Then, we tested a set of wildtype inducible promoters, and further used a hybrid strategy to create engineered promoters to expand expression strength and dynamics. Additionally, we tested the T7 RNA Polymerase-P T7 promoter system and reduced its leaky expression through promoter mutation for gene expression. By coupling random library construction with FACS screening, we further developed a synthetic T7 promoter library to confer a wider range of expression strength and dynamic characteristics. This study provides a set of valuable tools to engineer gene circuits in C. testosteroni, facilitating the establishment of the organism as a useful microbial chassis for bioremediation purposes.

Generation of thermostable Moloney murine leukemia virus reverse transcriptase variants using site saturation mutagenesis library and cell-free protein expression system.

PubMed

Katano, Yuta; Li, Tongyang; Baba, Misato; Nakamura, Miyo; Ito, Masaaki; Kojima, Kenji; Takita, Teisuke; Yasukawa, Kiyoshi

2017-12-01

We attempted to increase the thermostability of Moloney murine leukemia virus (MMLV) reverse transcriptase (RT). The eight-site saturation mutagenesis libraries corresponding to Ala70-Arg469 in the whole MMLV RT (Thr24-Leu671), in each of which 1 out of 50 amino acid residues was replaced with other amino acid residue, were constructed. Seven-hundred and sixty eight MMLV RT clones were expressed using a cell-free protein expression system, and their thermostabilities were assessed by the temperature of thermal treatment at which they retained cDNA synthesis activity. One clone D200C was selected as the most thermostable variant. The highest temperature of thermal treatment at which D200C exhibited cDNA synthesis activity was 57ºC, which was higher than for WT (53ºC). Our results suggest that a combination of site saturation mutagenesis library and cell-free protein expression system might be useful for generation of thermostable MMLV RT in a short period of time for expression and selection.

The construction of an EST database for Bombyx mori and its application

PubMed Central

Mita, Kazuei; Morimyo, Mitsuoki; Okano, Kazuhiro; Koike, Yoshiko; Nohata, Junko; Kawasaki, Hideki; Kadono-Okuda, Keiko; Yamamoto, Kimiko; Suzuki, Masataka G.; Shimada, Toru; Goldsmith, Marian R.; Maeda, Susumu

2003-01-01

To build a foundation for the complete genome analysis of Bombyx mori, we have constructed an EST database. Because gene expression patterns deeply depend on tissues as well as developmental stages, we analyzed many cDNA libraries prepared from various tissues and different developmental stages to cover the entire set of Bombyx genes. So far, the Bombyx EST database contains 35,000 ESTs from 36 cDNA libraries, which are grouped into ≈11,000 nonredundant ESTs with the average length of 1.25 kb. The comparison with FlyBase suggests that the present EST database, SilkBase, covers >55% of all genes of Bombyx. The fraction of library-specific ESTs in each cDNA library indicates that we have not yet reached saturation, showing the validity of our strategy for constructing an EST database to cover all genes. To tackle the coming saturation problem, we have checked two methods, subtraction and normalization, to increase coverage and decrease the number of housekeeping genes, resulting in a 5–11% increase of library-specific ESTs. The identification of a number of genes and comprehensive cloning of gene families have already emerged from the SilkBase search. Direct links of SilkBase with FlyBase and WormBase provide ready identification of candidate Lepidoptera-specific genes. PMID:14614147

An efficient strategy for cell-based antibody library selection using an integrated vector system.

PubMed

Yoon, Hyerim; Song, Jin Myung; Ryu, Chun Jeih; Kim, Yeon-Gu; Lee, Eun Kyo; Kang, Sunghyun; Kim, Sang Jick

2012-09-18

Cell panning of phage-displayed antibody library is a powerful tool for the development of therapeutic and imaging agents since disease-related cell surface proteins in native complex conformation can be directly targeted. Here, we employed a strategy taking advantage of an integrated vector system which allows rapid conversion of scFv-displaying phage into scFv-Fc format for efficient cell-based scFv library selection on a tetraspanin protein, CD9. A mouse scFv library constructed by using a phagemid vector, pDR-D1 was subjected to cell panning against stable CD9 transfectant, and the scFv repertoire from the enriched phage pool was directly transferred to a mammalian cassette vector, pDR-OriP-Fc1. The resulting constructs enabled transient expression of enough amounts of scFv-Fcs in HEK293E cells, and flow cytometric screening of binders for CD9 transfectant could be performed simply by using the culture supernatants. All three clones selected from the screening showed correct CD9-specificity. They could immunoprecipitate CD9 molecules out of the transfectant cell lysate and correctly stain endogenous CD9 expression on cancer cell membrane. Furthermore, competition assay with a known anti-CD9 monoclonal antibody (mAb) suggested that the binding epitopes of some of them overlap with that of the mAb which resides within the large extracellular loop of CD9. This study demonstrates that scFv-Fc from mammalian transient expression can be chosen as a reliable format for rapid screening and validation in cell-based scFv library selection, and the strategy described here will be applicable to efficient discovery of antibodies to diverse cell-surface targets.

A genome-wide inducible phenotypic screen identifies antisense RNA constructs silencing Escherichia coli essential genes.

PubMed

Meng, Jia; Kanzaki, Gregory; Meas, Diane; Lam, Christopher K; Crummer, Heather; Tain, Justina; Xu, H Howard

2012-04-01

Regulated antisense RNA (asRNA) expression has been employed successfully in Gram-positive bacteria for genome-wide essential gene identification and drug target determination. However, there have been no published reports describing the application of asRNA gene silencing for comprehensive analyses of essential genes in Gram-negative bacteria. In this study, we report the first genome-wide identification of asRNA constructs for essential genes in Escherichia coli. We screened 250 000 library transformants for conditional growth inhibitory recombinant clones from two shotgun genomic libraries of E. coli using a paired-termini expression vector (pHN678). After sequencing plasmid inserts of 675 confirmed inducer sensitive cell clones, we identified 152 separate asRNA constructs of which 134 inserts came from essential genes, while 18 originated from nonessential genes (but share operons with essential genes). Among the 79 individual essential genes silenced by these asRNA constructs, 61 genes (77%) engage in processes related to protein synthesis. The cell-based assays of an asRNA clone targeting fusA (encoding elongation factor G) showed that the induced cells were sensitized 12-fold to fusidic acid, a known specific inhibitor. Our results demonstrate the utility of the paired-termini expression vector and feasibility of large-scale gene silencing in E. coli using regulated asRNA expression. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Identification of transcripts related to high egg production in the chicken hypothalamus and pituitary gland.

PubMed

Shiue, Yow-Ling; Chen, Lih-Ren; Chen, Chih-Feng; Chen, Yi-Ling; Ju, Jhy-Phen; Chao, Ching-Hsien; Lin, Yuan-Ping; Kuo, Yu-Ming; Tang, Pin-Chi; Lee, Yen-Pai

2006-09-15

To identify transcripts related to high egg production expressed specifically in the hypothalamus and pituitary gland of the chicken, two subtracted cDNA libraries were constructed. Two divergently selected strains of Taiwan Country Chickens (TCCs), B (sire line) and L2 (dam line) were used; they had originated from a single population and were further subjected (since 1982) to selection for egg production to 40 wk of age and body weight/comb size, respectively. A total of 324 and 370 clones were identified from the L2-B (L2-subtract-B) and the B-L2 subtracted cDNA libraries, respectively. After sequencing and annotation, 175 and 136 transcripts that represented 53 known and 65 unknown non-redundant sequences were characterized in the L2-B subtracted cDNA library. Quantitative reverse-transcription (RT)-PCR was used to screen the mRNA expression levels of 32 randomly selected transcripts in another 78 laying hens from five different strains. These strains included the two original strains (B and L2) used to construct the subtracted cDNA libraries and an additional three commercial strains, i.e., Black- and Red-feather TCCs and Single-Comb White Leghorn (WL) layer. The mRNA expression levels of 16 transcripts were significantly higher in the L2 than in the B strain, whereas the mRNA expression levels of nine transcripts, BDH, NCAM1, PCDHA@, PGDS, PLAG1, PRL, SAR1A, SCG2 and STMN2, were significantly higher in two high egg production strains, L2 and Single-Comb WL; this indicated their usefulness as molecular markers of high egg production.

Illumina Unamplified Indexed Library Construction: An Automated Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hack, Christopher A.; Sczyrba, Alexander; Cheng, Jan-Fang

Manual library construction is a limiting factor in Illumina sequencing. Constructing libraries by hand is costly, time-consuming, low-throughput, and ergonomically hazardous, and constructing multiple libraries introduces risk of library failure due to pipetting errors. The ability to construct multiple libraries simultaneously in automated fashion represents significant cost and time savings. Here we present a strategy to construct up to 96 unamplified indexed libraries using Illumina TruSeq reagents and a Biomek FX robotic platform. We also present data to indicate that this library construction method has little or no risk of cross-contamination between samples.

Construction of high-quality Caco-2 three-frame cDNA library and its application to yeast two-hybrid for the human astrovirus protein-protein interaction.

PubMed

Zhao, Wei; Li, Xin; Liu, Wen-Hui; Zhao, Jian; Jin, Yi-Ming; Sui, Ting-Ting

2014-09-01

Human epithelial colorectal adenocarcinoma (Caco-2) cells are widely used as an in vitro model of the human small intestinal mucosa. Caco-2 cells are host cells of the human astrovirus (HAstV) and other enteroviruses. High quality cDNA libraries are pertinent resources and critical tools for protein-protein interaction research, but are currently unavailable for Caco-2 cells. To construct a three-open reading frame, full length-expression cDNA library from the Caco-2 cell line for application to HAstV protein-protein interaction screening, total RNA was extracted from Caco-2 cells. The switching mechanism at the 5' end of the RNA transcript technique was used for cDNA synthesis. Double-stranded cDNA was digested by Sfi I and ligated to reconstruct a pGADT7-Sfi I three-frame vector. The ligation mixture was transformed into Escherichia coli HST08 premium electro cells by electroporation to construct the primary cDNA library. The library capacity was 1.0×10(6)clones. Gel electrophoresis results indicated that the fragments ranged from 0.5kb to 4.2kb. Randomly picked clones show that the recombination rate was 100%. The three-frame primary cDNA library plasmid mixture (5×10(5)cfu) was also transformed into E. coli HST08 premium electro cells, and all clones were harvested to amplify the cDNA library. To detect the sufficiency of the cDNA library, HAstV capsid protein as bait was screened and tested against the Caco-2 cDNA library by a yeast two-hybrid (Y2H) system. A total of 20 proteins were found to interact with the capsid protein. These results showed that a high-quality three-frame cDNA library from Caco-2 cells was successfully constructed. This library was efficient for the application to the Y2H system, and could be used for future research. Copyright © 2014 Elsevier B.V. All rights reserved.

A Blumeria graminisf.sp. hordei BAC library--contig building and microsynteny studies.

PubMed

Pedersen, Carsten; Wu, Boqian; Giese, Henriette

2002-11-01

A bacterial artificial chromosome (BAC) library of Blumeria graminis f.sp. hordei, containing 12,000 clones with an average insert size of 41 kb, was constructed. The library represents about three genome equivalents and BAC-end sequencing showed a high content of repetitive sequences, making contig-building difficult. To identify overlapping clones, several strategies were used: colony hybridisation, PCR screening, fingerprinting techniques and the use of single-copy expressed sequence tags. The latter proved to be the most efficient method for identification of overlapping clones. Two contigs, at or close to avirulence loci, were constructed. Single nucleotide polymorphism (SNP) markers were developed from BAC-end sequences to link the contigs to the genetic maps. Two other BAC contigs were used to study microsynteny between B. graminis and two other ascomycetes, Neurospora crassa and Aspergillus fumigatus. The library provides an invaluable tool for the isolation of avirulence genes from B. graminis and for the study of gene synteny between this fungus and other fungi.

Phage display peptide libraries: deviations from randomness and correctives

PubMed Central

Ryvkin, Arie; Ashkenazy, Haim; Weiss-Ottolenghi, Yael; Piller, Chen; Pupko, Tal; Gershoni, Jonathan M

2018-01-01

Abstract Peptide-expressing phage display libraries are widely used for the interrogation of antibodies. Affinity selected peptides are then analyzed to discover epitope mimetics, or are subjected to computational algorithms for epitope prediction. A critical assumption for these applications is the random representation of amino acids in the initial naïve peptide library. In a previous study, we implemented next generation sequencing to evaluate a naïve library and discovered severe deviations from randomness in UAG codon over-representation as well as in high G phosphoramidite abundance causing amino acid distribution biases. In this study, we demonstrate that the UAG over-representation can be attributed to the burden imposed on the phage upon the assembly of the recombinant Protein 8 subunits. This was corrected by constructing the libraries using supE44-containing bacteria which suppress the UAG driven abortive termination. We also demonstrate that the overabundance of G stems from variant synthesis-efficiency and can be corrected using compensating oligonucleotide-mixtures calibrated by mass spectroscopy. Construction of libraries implementing these correctives results in markedly improved libraries that display random distribution of amino acids, thus ensuring that enriched peptides obtained in biopanning represent a genuine selection event, a fundamental assumption for phage display applications. PMID:29420788

Libraries of Synthetic TALE-Activated Promoters: Methods and Applications.

PubMed

Schreiber, T; Tissier, A

2016-01-01

The discovery of proteins with programmable DNA-binding specificities triggered a whole array of applications in synthetic biology, including genome editing, regulation of transcription, and epigenetic modifications. Among those, transcription activator-like effectors (TALEs) due to their natural function as transcription regulators, are especially well-suited for the development of orthogonal systems for the control of gene expression. We describe here the construction and testing of libraries of synthetic TALE-activated promoters which are under the control of a single TALE with a given DNA-binding specificity. These libraries consist of a fixed DNA-binding element for the TALE, a TATA box, and variable sequences of 19 bases upstream and 43 bases downstream of the DNA-binding element. These libraries were cloned using a Golden Gate cloning strategy making them usable as standard parts in a modular cloning system. The broad range of promoter activities detected and the versatility of these promoter libraries make them valuable tools for applications in the fine-tuning of expression in metabolic engineering projects or in the design and implementation of regulatory circuits. © 2016 Elsevier Inc. All rights reserved.

A variety of human monoclonal antibodies against epidermal growth factor receptor isolated from a phage antibody library.

PubMed

Kurosawa, Gene; Kondo, Mariko; Kurosawa, Yoshikazu

2016-11-04

When the technology for constructing human antibody (Ab) libraries using a phage-display system was developed, many researchers in Ab-related fields anticipated that it would be widely applied to the development of pharmaceutical drugs against various diseases, including cancers. However, successful examples of such applications are very limited. Moreover, researchers who utilize phage-display technology now show divergent ways of thinking about phage Ab libraries. For example, there is debate about what should be the source of V H and V L genes for the construction of libraries to cover the whole repertoire of Abs present in the human body. In the immune system, the introduction of mutations into V genes followed by selection based on binding activity, termed Ab maturation, is required for the production of Abs exhibiting high affinity to the antigen (Ag). Therefore, introduction of mutations and selection are required for isolation of Abs with high affinity after isolation of clones from phage Ab libraries. We constructed a large human Ab library termed AIMS, developed a screening method termed ICOS, and succeeded in isolating many human monoclonal Abs (mAbs) that specifically and strongly bind to various tumor-associated Ags. Eight anti-EGFR mAbs were included, which we characterized. These mAbs showed various different activities against EGFR-expressing cancer cells. In this paper, we describe these data and discuss the possibility and necessity that the mAbs isolated from the AIMS library might be developed as therapeutic drugs against cancers without introduction of mutations. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Update of the Diatom EST Database: a new tool for digital transcriptomics

PubMed Central

Maheswari, Uma; Mock, Thomas; Armbrust, E. Virginia; Bowler, Chris

2009-01-01

The Diatom Expressed Sequence Tag (EST) Database was constructed to provide integral access to ESTs from these ecologically and evolutionarily interesting microalgae. It has now been updated with 130 000 Phaeodactylum tricornutum ESTs from 16 cDNA libraries and 77 000 Thalassiosira pseudonana ESTs from seven libraries, derived from cells grown in different nutrient and stress regimes. The updated relational database incorporates results from statistical analyses such as log-likelihood ratios and hierarchical clustering, which help to identify differentially expressed genes under different conditions, and allow similarities in gene expression in different libraries to be investigated in a functional context. The database also incorporates links to the recently sequenced genomes of P. tricornutum and T. pseudonana, enabling an easy cross-talk between the expression pattern of diatom orthologs and the genome browsers. These improvements will facilitate exploration of diatom responses to conditions of ecological relevance and will aid gene function identification of diatom-specific genes and in silico gene prediction in this largely unexplored class of eukaryotes. The updated Diatom EST Database is available at http://www.biologie.ens.fr/diatomics/EST3. PMID:19029140

Methods for transforming and expression screening of filamentous fungal cells with a DNA library

DOEpatents

Teter, Sarah; Lamsa, Michael; Cherry, Joel; Ward, Connie

2015-06-02

The present invention relates to methods for expression screening of filamentous fungal transformants, comprising: (a) isolating single colony transformants of a DNA library introduced into E. coli; (b) preparing DNA from each of the single colony E. coli transformants; (c) introducing a sample of each of the DNA preparations of step (b) into separate suspensions of protoplasts of a filamentous fungus to obtain transformants thereof, wherein each transformant contains one or more copies of an individual polynucleotide from the DNA library; (d) growing the individual filamentous fungal transformants of step (c) on selective growth medium, thereby permitting growth of the filamentous fungal transformants, while suppressing growth of untransformed filamentous fungi; and (e) measuring activity or a property of each polypeptide encoded by the individual polynucleotides. The present invention also relates to isolated polynucleotides encoding polypeptides of interest obtained by such methods, to nucleic acid constructs, expression vectors, and recombinant host cells comprising the isolated polynucleotides, and to methods of producing the polypeptides encoded by the isolated polynucleotides.

[Construction and analysis of a forward and reverse subtractive cDNA library from leaves and stem of Polygonum sibiricum Laxm. under salt stress].

PubMed

Liu, Guan-Jun; Liu, Ming-Kun; Xu, Zhi-Ru; Yan, Xiu-Feng; Wei, Zhi-Gang; Yang, Chuan-Ping

2009-04-01

Using cDNAs prepared from the leaves and stems of Polygonum sibiricum Laxm. treated with NaHCO3 stress for 48 h as testers and cDNAs from unstressed P. sibiricum leaves and stems as drivers library, suppression subtractive hybridization (SSH) was employed to construct a cDNA subtracted library, which contained 2 282 valid sequences including 598 ESTs in the stems forward SSH library and 490 ESTs in the stem reverse SSH library, 627 ESTs in the leaf forward SSH library and 567 in the leaf reverse SSH library. According to the functional catalogue of MIPs and the comparison of the reverse and forward SSH libraries of the stem and leaf, the responses to NaHCO3 stress were different between leaf and stem, except for the same trend in cell rescue defense and transport facilitation. The trend in the metabolism, energy, photosynthesis, protein synthesis, transcription, and signal transduction was opposite. RT-PCR analysis demonstrated that the expression of 12 putative stress related genes in the NaHCO3-treated leaves and stems was different from that in the untreated leaves and stems. This indicated that different mechanisms might be responsible for reactions of leaf and stem in P. sibiricum. The results from this study are useful in understanding the molecular mechanism of saline-alkali tolerance in P. sibiricum.

Micropreparative capillary gel electrophoresis of DNA: rapid expressed sequence tag library construction.

PubMed

Shi, Liang; Khandurina, Julia; Ronai, Zsolt; Li, Bi-Yu; Kwan, Wai King; Wang, Xun; Guttman, András

2003-01-01

A capillary gel electrophoresis based automated DNA fraction collection technique was developed to support a novel DNA fragment-pooling strategy for expressed sequence tag (EST) library construction. The cDNA population is first cleaved by BsaJ I and EcoR I restriction enzymes, and then subpooled by selective ligation with specific adapters followed by polymerase chain reaction (PCR) amplification and labeling. Combination of this cDNA fingerprinting method with high-resolution capillary gel electrophoresis separation and precise fractionation of individual cDNA transcript representatives avoids redundant fragment selection and concomitant repetitive sequencing of abundant transcripts. Using a computer-controlled capillary electrophoresis device the transcript representatives were separated by their size and fractions were automatically collected in every 30 s into 96-well plates. The high resolving power of the sieving matrix ensured sequencing grade separation of the DNA fragments (i.e., single-base resolution) and successful fraction collection. Performance and precision of the fraction collection procedure was validated by PCR amplification of the collected DNA fragments followed by capillary electrophoresis analysis for size and purity verification. The collected and PCR-amplified transcript representatives, ranging up to several hundred base pairs, were then sequenced to create an EST library.

Versatile P(acman) BAC Libraries for Transgenesis Studies in Drosophila melanogaster

DOE Office of Scientific and Technical Information (OSTI.GOV)

Venken, Koen J.T.; Carlson, Joseph W.; Schulze, Karen L.

2009-04-21

We constructed Drosophila melanogaster BAC libraries with 21-kb and 83-kb inserts in the P(acman) system. Clones representing 12-fold coverage and encompassing more than 95percent of annotated genes were mapped onto the reference genome. These clones can be integrated into predetermined attP sites in the genome using Phi C31 integrase to rescue mutations. They can be modified through recombineering, for example to incorporate protein tags and assess expression patterns.

A novel helper phage enabling construction of genome-scale ORF-enriched phage display libraries.

PubMed

Gupta, Amita; Shrivastava, Nimisha; Grover, Payal; Singh, Ajay; Mathur, Kapil; Verma, Vaishali; Kaur, Charanpreet; Chaudhary, Vijay K

2013-01-01

Phagemid-based expression of cloned genes fused to the gIIIP coding sequence and rescue using helper phages, such as VCSM13, has been used extensively for constructing large antibody phage display libraries. However, for randomly primed cDNA and gene fragment libraries, this system encounters reading frame problems wherein only one of 18 phages display the translated foreign peptide/protein fused to phagemid-encoded gIIIP. The elimination of phages carrying out-of-frame inserts is vital in order to improve the quality of phage display libraries. In this study, we designed a novel helper phage, AGM13, which carries trypsin-sensitive sites within the linker regions of gIIIP. This renders the phage highly sensitive to trypsin digestion, which abolishes its infectivity. For open reading frame (ORF) selection, the phagemid-borne phages are rescued using AGM13, so that clones with in-frame inserts express fusion proteins with phagemid-encoded trypsin-resistant gIIIP, which becomes incorporated into the phages along with a few copies of AGM13-encoded trypsin-sensitive gIIIP. In contrast, clones with out-of-frame inserts produce phages carrying only AGM13-encoded trypsin-sensitive gIIIP. Trypsin treatment of the phage population renders the phages with out-of-frame inserts non-infectious, whereas phages carrying in-frame inserts remain fully infectious and can hence be enriched by infection. This strategy was applied efficiently at a genome scale to generate an ORF-enriched whole genome fragment library from Mycobacterium tuberculosis, in which nearly 100% of the clones carried in-frame inserts after selection. The ORF-enriched libraries were successfully used for identification of linear and conformational epitopes for monoclonal antibodies specific to mycobacterial proteins.

Non-enzymatic hydrolysis of RNA in workers of the ant Nylanderia pubens

USDA-ARS?s Scientific Manuscript database

During preparation of total RNA from Nylanderia pubens (Forel) workers for use in expression library construction, severe RNA degradation consistently occurred that was masked by spectrophotometric analysis but clearly evident by microfluidic-based assay. Although not specifically identified, the ...

A highly functional synthetic phage display library containing over 40 billion human antibody clones.

PubMed

Weber, Marcel; Bujak, Emil; Putelli, Alessia; Villa, Alessandra; Matasci, Mattia; Gualandi, Laura; Hemmerle, Teresa; Wulhfard, Sarah; Neri, Dario

2014-01-01

Several synthetic antibody phage display libraries have been created and used for the isolation of human monoclonal antibodies. The performance of antibody libraries, which is usually measured in terms of their ability to yield high-affinity binding specificities against target proteins of interest, depends both on technical aspects (such as library size and quality of cloning) and on design features (which influence the percentage of functional clones in the library and their ability to be used for practical applications). Here, we describe the design, construction and characterization of a combinatorial phage display library, comprising over 40 billion human antibody clones in single-chain fragment variable (scFv) format. The library was designed with the aim to obtain highly stable antibody clones, which can be affinity-purified on protein A supports, even when used in scFv format. The library was found to be highly functional, as >90% of randomly selected clones expressed the corresponding antibody. When selected against more than 15 antigens from various sources, the library always yielded specific and potent binders, at a higher frequency compared to previous antibody libraries. To demonstrate library performance in practical biomedical research projects, we isolated the human antibody G5, which reacts both against human and murine forms of the alternatively spliced BCD segment of tenascin-C, an extracellular matrix component frequently over-expressed in cancer and in chronic inflammation. The new library represents a useful source of binding specificities, both for academic research and for the development of antibody-based therapeutics.

A Highly Functional Synthetic Phage Display Library Containing over 40 Billion Human Antibody Clones

PubMed Central

Weber, Marcel; Bujak, Emil; Putelli, Alessia; Villa, Alessandra; Matasci, Mattia; Gualandi, Laura; Hemmerle, Teresa; Wulhfard, Sarah; Neri, Dario

2014-01-01

Several synthetic antibody phage display libraries have been created and used for the isolation of human monoclonal antibodies. The performance of antibody libraries, which is usually measured in terms of their ability to yield high-affinity binding specificities against target proteins of interest, depends both on technical aspects (such as library size and quality of cloning) and on design features (which influence the percentage of functional clones in the library and their ability to be used for practical applications). Here, we describe the design, construction and characterization of a combinatorial phage display library, comprising over 40 billion human antibody clones in single-chain fragment variable (scFv) format. The library was designed with the aim to obtain highly stable antibody clones, which can be affinity-purified on protein A supports, even when used in scFv format. The library was found to be highly functional, as >90% of randomly selected clones expressed the corresponding antibody. When selected against more than 15 antigens from various sources, the library always yielded specific and potent binders, at a higher frequency compared to previous antibody libraries. To demonstrate library performance in practical biomedical research projects, we isolated the human antibody G5, which reacts both against human and murine forms of the alternatively spliced BCD segment of tenascin-C, an extracellular matrix component frequently over-expressed in cancer and in chronic inflammation. The new library represents a useful source of binding specificities, both for academic research and for the development of antibody-based therapeutics. PMID:24950200

Cloning and expression of clt genes encoding milk-clotting proteases from Myxococcus xanthus 422.

PubMed

Poza, M; Prieto-Alcedo, M; Sieiro, C; Villa, T G

2004-10-01

The screening of a gene library of the milk-clotting strain Myxococcus xanthus 422 constructed in Escherichia coli allowed the description of eight positive clones containing 26 open reading frames. Only three of them (cltA, cltB, and cltC) encoded proteins that exhibited intracellular milk-clotting ability in E. coli, Saccharomyces cerevisiae, and Pichia pastoris expression systems.

A Novel Approach to the Elucidation of the Mechanism of Development of Androgen-Independent Growth of Prostate Cancer

DTIC Science & Technology

2001-01-01

with 1.0 with differential hybridization to the two probes. Phage plaques corresponding ml of RIPA buffer with protease inhibitors (PBS, 1% NP40, 0.5...hybridized to radiolabeled probe prepared from plaque-purified phage . at 10,000 X g for 20 min; supernatants were collected and centrifuged again to...Screening. Lambda phage plaques from the primary unamplified Differential expression screening of cDNA libraries constructed CWR22 library were plated

Generation of dTALEs and Libraries of Synthetic TALE-Activated Promoters for Engineering of Gene Regulatory Networks in Plants.

PubMed

Schreiber, Tom; Tissier, Alain

2017-01-01

Transcription factors with programmable DNA-binding specificity constitute valuable tools for the design of orthogonal gene regulatory networks for synthetic biology. Transcription activator-like effectors (TALEs), as natural transcription regulators, were used to design, build, and test libraries of synthetic TALE-activated promoters (STAPs) that show a broad range of expression levels in plants. In this chapter, we present protocols for the construction of artificial TALEs and corresponding STAPs.

Linkage of Recognition and Replication Functions by Assembling Combinatorial Antibody Fab Libraries Along Phage Surfaces

NASA Astrophysics Data System (ADS)

Kang, Angray S.; Barbas, Carlos F.; Janda, Kim D.; Benkovic, Stephen J.; Lerner, Richard A.

1991-05-01

We describe a method based on a phagemid vector with helper phage rescue for the construction and rapid analysis of combinatorial antibody Fab libraries. This approach should allow the generation and selection of many monoclonal antibodies. Antibody genes are expressed in concert with phage morphogenesis, thereby allowing incorporation of functional Fab molecules along the surface of filamentous phage. The power of the method depends upon the linkage of recognition and replication functions and is not limited to antibody molecules.

Cloning and characterization of a novel α-amylase from a fecal microbial metagenome.

PubMed

Xu, Bo; Yang, Fuya; Xiong, Caiyun; Li, Junjun; Tang, Xianghua; Zhou, Junpei; Xie, Zhenrong; Ding, Junmei; Yang, Yunjuan; Huang, Zunxi

2014-04-01

To isolate novel and useful microbial enzymes from uncultured gastrointestinal microorganisms, a fecal microbial metagenomic library of the pygmy loris was constructed. The library was screened for amylolytic activity, and 8 of 50,000 recombinant clones showed amylolytic activity. Subcloning and sequence analysis of a positive clone led to the identification a novel gene (amyPL) coding for α-amylase. AmyPL was expressed in Escherichia coli BL21 (DE3) and the purified AmyPL was enzymatically characterized. This study is the first to report the molecular and biochemical characterization of a novel α-amylase from a gastrointestinal metagenomic library.

Construction of a cDNA library from female adult of Toxocara canis, and analysis of EST and immune-related genes expressions.

PubMed

Zhou, Rongqiong; Xia, Qingyou; Huang, Hancheng; Lai, Min; Wang, Zhenxin

2011-10-01

Toxocara canis is a widespread intestinal nematode parasite of dogs, which can also cause disease in humans. We employed an expressed sequence tag (EST) strategy in order to study gene-expression including development, digestion and reproduction of T. canis. ESTs provided a rapid way to identify genes, particularly in organisms for which we have very little molecular information. In this study, a cDNA library was constructed from a female adult of T. canis and 215 high-quality ESTs from 5'-ends of the cDNA clones representing 79 unigenes were obtained. The titer of the primary cDNA library was 1.83×10(6)pfu/mL with a recombination rate of 99.33%. Most of the sequences ranged from 300 to 900bp with an average length of 656bp. Cluster analysis of these ESTs allowed identification of 79 unique sequences containing 28 contigs and 51 singletons. BLASTX searches revealed that 18 unigenes (22.78% of the total) or 70 ESTs (32.56% of the total) were novel genes that had no significant matches to any protein sequences in the public databases. The rest of the 61 unigenes (77.22% of the total) or 145 ESTs (67.44% of the total) were closely matched to the known genes or sequences deposited in the public databases. These genes were classified into seven groups based on their known or putative biological functions. We also confirmed the gene expression patterns of several immune-related genes using RT-PCR examination. This work will provide a valuable resource for the further investigations in the stage-, sex- and tissue-specific gene transcription or expression. Copyright © 2011. Published by Elsevier Inc.

Construction of cDNA library and preliminary analysis of expressed sequence tags from Siberian tiger

PubMed Central

Liu, Chang-Qing; Lu, Tao-Feng; Feng, Bao-Gang; Liu, Dan; Guan, Wei-Jun; Ma, Yue-Hui

2010-01-01

In this study we successfully constructed a full-length cDNA library from Siberian tiger, Panthera tigris altaica, the most well-known wild Animal. Total RNA was extracted from cultured Siberian tiger fibroblasts in vitro. The titers of primary and amplified libraries were 1.30×106 pfu/ml and 1.62×109 pfu/ml respectively. The proportion of recombinants from unamplified library was 90.5% and average length of exogenous inserts was 1.13 kb. A total of 282 individual ESTs with sizes ranging from 328 to 1,142bps were then analyzed the BLASTX score revealed that 53.9% of the sequences were classified as strong match, 38.6% as nominal and 7.4% as weak match. 28.0% of them were found to be related to enzyme/catalytic protein, 20.9% ESTs to metabolism, 13.1% ESTs to transport, 12.1% ESTs to signal transducer/cell communication, 9.9% ESTs to structure protein, 3.9% ESTs to immunity protein/defense metabolism, 3.2% ESTs to cell cycle, and 8.9 ESTs classified as novel genes. These results demonstrated that the reliability and representativeness of the cDNA library attained to the requirements of a standard cDNA library. This library provided a useful platform for the functional genomic research of Siberian tigers. PMID:20941376

Distinct profiles of expressed sequence tags during intestinal regeneration in the sea cucumber Holothuria glaberrima

PubMed Central

Rojas-Cartagena, Carmencita; Ortíz-Pineda, Pablo; Ramírez-Gómez, Francisco; Suárez-Castillo, Edna C.; Matos-Cruz, Vanessa; Rodríguez, Carlos; Ortíz-Zuazaga, Humberto; García-Arrarás, José E.

2010-01-01

Repair and regeneration are key processes for tissue maintenance, and their disruption may lead to disease states. Little is known about the molecular mechanisms that underline the repair and regeneration of the digestive tract. The sea cucumber Holothuria glaberrima represents an excellent model to dissect and characterize the molecular events during intestinal regeneration. To study the gene expression profile, cDNA libraries were constructed from normal, 3-day, and 7-day regenerating intestines of H. glaberrima. Clones were randomly sequenced and queried against the nonredundant protein database at the National Center for Biotechnology Information. RT-PCR analyses were made of several genes to determine their expression profile during intestinal regeneration. A total of 5,173 sequences from three cDNA libraries were obtained. About 46.2, 35.6, and 26.2% of the sequences for the normal, 3-days, and 7-days cDNA libraries, respectively, shared significant similarity with known sequences in the protein database of GenBank but only present 10% of similarity among them. Analysis of the libraries in terms of functional processes, protein domains, and most common sequences suggests that a differential expression profile is taking place during the regeneration process. Further examination of the expressed sequence tag dataset revealed that 12 putative genes are differentially expressed at significant level (R > 6). Experimental validation by RT-PCR analysis reveals that at least three genes (unknown C-4677-1, melanotransferrin, and centaurin) present a differential expression during regeneration. These findings strongly suggest that the gene expression profile varies among regeneration stages and provide evidence for the existence of differential gene expression. PMID:17579180

A compact, in vivo screen of all 6-mers reveals drivers of tissue-specific expression and guides synthetic regulatory element design.

PubMed

Smith, Robin P; Riesenfeld, Samantha J; Holloway, Alisha K; Li, Qiang; Murphy, Karl K; Feliciano, Natalie M; Orecchia, Lorenzo; Oksenberg, Nir; Pollard, Katherine S; Ahituv, Nadav

2013-07-18

Large-scale annotation efforts have improved our ability to coarsely predict regulatory elements throughout vertebrate genomes. However, it is unclear how complex spatiotemporal patterns of gene expression driven by these elements emerge from the activity of short, transcription factor binding sequences. We describe a comprehensive promoter extension assay in which the regulatory potential of all 6 base-pair (bp) sequences was tested in the context of a minimal promoter. To enable this large-scale screen, we developed algorithms that use a reverse-complement aware decomposition of the de Bruijn graph to design a library of DNA oligomers incorporating every 6-bp sequence exactly once. Our library multiplexes all 4,096 unique 6-mers into 184 double-stranded 15-bp oligomers, which is sufficiently compact for in vivo testing. We injected each multiplexed construct into zebrafish embryos and scored GFP expression in 15 tissues at two developmental time points. Twenty-seven constructs produced consistent expression patterns, with the majority doing so in only one tissue. Functional sequences are enriched near biologically relevant genes, match motifs for developmental transcription factors, and are required for enhancer activity. By concatenating tissue-specific functional sequences, we generated completely synthetic enhancers for the notochord, epidermis, spinal cord, forebrain and otic lateral line, and show that short regulatory sequences do not always function modularly. This work introduces a unique in vivo catalog of short, functional regulatory sequences and demonstrates several important principles of regulatory element organization. Furthermore, we provide resources for designing compact, reverse-complement aware k-mer libraries.

Identification of differentially-expressed genes potentially implicated in drought response in pitaya (Hylocereus undatus) by suppression subtractive hybridization and cDNA microarray analysis.

PubMed

Fan, Qing-Jie; Yan, Feng-Xia; Qiao, Guang; Zhang, Bing-Xue; Wen, Xiao-Peng

2014-01-01

Drought is one of the most severe threats to the growth, development and yield of plant. In order to unravel the molecular basis underlying the high tolerance of pitaya (Hylocereus undatus) to drought stress, suppression subtractive hybridization (SSH) and cDNA microarray approaches were firstly combined to identify the potential important or novel genes involved in the plant responses to drought stress. The forward (drought over drought-free) and reverse (drought-free over drought) suppression subtractive cDNA libraries were constructed using in vitro shoots of cultivar 'Zihonglong' exposed to drought stress and drought-free (control). A total of 2112 clones, among which half were from either forward or reverse SSH library, were randomly picked up to construct a pitaya cDNA microarray. Microarray analysis was carried out to verify the expression fluctuations of this set of clones upon drought treatment compared with the controls. A total of 309 expressed sequence tags (ESTs), 153 from forward library and 156 from reverse library, were obtained, and 138 unique ESTs were identified after sequencing by clustering and blast analyses, which included genes that had been previously reported as responsive to water stress as well as some functionally unknown genes. Thirty six genes were mapped to 47 KEGG pathways, including carbohydrate metabolism, lipid metabolism, energy metabolism, nucleotide metabolism, and amino acid metabolism of pitaya. Expression analysis of the selected ESTs by reverse transcriptase polymerase chain reaction (RT-PCR) corroborated the results of differential screening. Moreover, time-course expression patterns of these selected ESTs further confirmed that they were closely responsive to drought treatment. Among the differentially expressed genes (DEGs), many are related to stress tolerances including drought tolerance. Thereby, the mechanism of drought tolerance of this pitaya genotype is a very complex physiological and biochemical process, in which multiple metabolism pathways and many genes were implicated. The data gained herein provide an insight into the mechanism underlying the drought stress tolerance of pitaya, as well as may facilitate the screening of candidate genes for drought tolerance. © 2013 Elsevier B.V. All rights reserved.

Library Construction from Subnanogram DNA for Pelagic Sea Water and Deep-Sea Sediments

PubMed Central

Hirai, Miho; Nishi, Shinro; Tsuda, Miwako; Sunamura, Michinari; Takaki, Yoshihiro; Nunoura, Takuro

2017-01-01

Shotgun metagenomics is a low biased technology for assessing environmental microbial diversity and function. However, the requirement for a sufficient amount of DNA and the contamination of inhibitors in environmental DNA leads to difficulties in constructing a shotgun metagenomic library. We herein examined metagenomic library construction from subnanogram amounts of input environmental DNA from subarctic surface water and deep-sea sediments using two library construction kits: the KAPA Hyper Prep Kit and Nextera XT DNA Library Preparation Kit, with several modifications. The influence of chemical contaminants associated with these environmental DNA samples on library construction was also investigated. Overall, shotgun metagenomic libraries were constructed from 1 pg to 1 ng of input DNA using both kits without harsh library microbial contamination. However, the libraries constructed from 1 pg of input DNA exhibited larger biases in GC contents, k-mers, or small subunit (SSU) rRNA gene compositions than those constructed from 10 pg to 1 ng DNA. The lower limit of input DNA for low biased library construction in this study was 10 pg. Moreover, we revealed that technology-dependent biases (physical fragmentation and linker ligation vs. tagmentation) were larger than those due to the amount of input DNA. PMID:29187708

Construction and characterization of a normalized cDNA library of Nannochloropsis oculata (Eustigmatophyceae)

NASA Astrophysics Data System (ADS)

Yu, Jianzhong; Ma, Xiaolei; Pan, Kehou; Yang, Guanpin; Yu, Wengong

2010-07-01

We constructed and characterized a normalized cDNA library of Nannochloropsis oculata CS-179, and obtained 905 nonredundant sequences (NRSs) ranging from 431-1 756 bp in length. Among them, 496 were very similar to nonredundant ones in the GenBank ( E ≤1.0e-05), and 349 ESTs had significant hits with the clusters of eukaryotic orthologous groups (KOG). Bases G and/or C at the third position of codons of 14 amino acid residues suggested a strong bias in the conserved domain of 362 NRSs (>60%). We also identified the unigenes encoding phosphorus and nitrogen transporters, suggesting that N. oculata could efficiently transport and metabolize phosphorus and nitrogen, and recognized the unigenes that involved in biosynthesis and storage of both fatty acids and polyunsaturated fatty acids (PUFAs), which will facilitate the demonstration of eicosapentaenoic acid (EPA) biosynthesis pathway of N. oculata. In comparison with the original cDNA library, the normalized library significantly increased the efficiencies of random sequencing and rarely expressed genes discovering, and decreased the frequency of abundant gene sequences.

Construction and characterization of a highly reactive chicken-derived single-chain variable fragment (scFv) antibody against Staphylococcus aureus developed with the T7 phage display system.

PubMed

Li, Jingquan; Xu, Yongping; Wang, Xitao; Li, Yuan; Wang, Lili; Li, Xiaoyu

2016-06-01

The purpose of this study was to construct a single-chain variable fragment (scFv) antibody from chicken egg yolk immunoglobulin (IgY) by means of genetic engineering and subsequent panning for a specific antibody against Staphylococcus aureus. We amplified the scFv using blood and spleen obtained from 100-day-old Roman chickens immunized with inactivated S. aureus and subsequently constructed a T7 phage display antibody library using phage display technology. Four non-repeated blood scFv and 6 spleen scFv were obtained following 3 rounds of panning of the T7 phage display antibody library, enzyme-linked immunosorbent assay and sequencing. These 10 scFv were cloned into the prokaryotic expression vector pCold I with expression induced at a low temperature. Four soluble proteins were obtained. Among them, soluble protein SFV6 derived from the spleen showed good reactivity against S. aureus using indirect ELISA and produced a particularly strong antibacterial effect in vitro. We were successful in isolating a highly specific scFv antibody against S. aureus from the spleen phage display library. This study provides a simple and rapid method for the quick preparation of a large number of antibodies against S. aureus and provides the foundation for the positioning of antibodies in the organism and the study of the antibacterial mechanism through which the antibody functions. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification of gene fragments related to nitrogen deficiency in Eichhornia crassipes (Pontederiaceae).

PubMed

Fu, Minghui; Jiang, Lihua; Li, Yuanmei; Yan, Guohua; Zheng, Lijun; Jinping, Peng

2014-12-01

Eichhornia crassipes is an aquatic plant native to the Amazon River Basin. It has become a serious weed in freshwater habitats in rivers, lakes and reservoirs both in tropical and warm temperate areas worldwide. Some research has stated that it can be used for water phytoremediation, due to its strong assimilation of nitrogen and phosphorus, and the accumulation of heavy metals, and its growth and spread may play an important role in environmental ecology. In order to explore the molecular mechanism of E. crassipes to responses to nitrogen deficiency, we constructed forward and reversed subtracted cDNA libraries for E. crassipes roots under nitrogen deficient condition using a suppressive subtractive hybridization (SSH) method. The forward subtraction included 2,100 clones, and the reversed included 2,650 clones. One thousand clones were randomly selected from each library for sequencing. About 737 (527 unigenes) clones from the forward library and 757 (483 unigenes) clones from the reversed library were informative. Sequence BlastX analysis showed that there were more transporters and adenosylhomocysteinase-like proteins in E. crassipes cultured in nitrogen deficient medium; while, those cultured in nitrogen replete medium had more proteins such as UBR4-like e3 ubiquitin-protein ligase and fasciclin-like arabinogalactan protein 8-like, as well as more cytoskeletal proteins, including actin and tubulin. Cluster of Orthologous Group (COG) analysis also demonstrated that in the forward library, the most ESTs were involved in coenzyme transportation and metabolism. In the reversed library, cytoskeletal ESTs were the most abundant. Gene Ontology (GO) analysis categories demonstrated that unigenes involved in binding, cellular process and electron carrier were the most differentially expressed unigenes between the forward and reversed libraries. All these results suggest that E. crassipes can respond to different nitrogen status by efficiently regulating and controlling some transporter gene expressions, certain metabolism processes, specific signal transduction pathways and cytoskeletal construction.

Screening and analyzing genes associated with Amur tiger placental development.

PubMed

Li, Q; Lu, T F; Liu, D; Hu, P F; Sun, B; Ma, J Z; Wang, W J; Wang, K F; Zhang, W X; Chen, J; Guan, W J; Ma, Y H; Zhang, M H

2014-09-26

The Amur tiger is a unique endangered species in the world, and thus, protection of its genetic resources is extremely important. In this study, an Amur tiger placenta cDNA library was constructed using the SMART cDNA Library Construction kit. A total of 508 colonies were sequenced, in which 205 (76%) genes were annotated and mapped to 74 KEGG pathways, including 29 metabolism, 29 genetic information processing, 4 environmental information processing, 7 cell motility, and 5 organismal system pathways. Additionally, PLAC8, PEG10 and IGF-II were identified after screening genes from the expressed sequence tags, and they were associated with placental development. These findings could lay the foundation for future functional genomic studies of the Amur tiger.

De novo Transcriptome Assembly of Common Wild Rice (Oryza rufipogon Griff.) and Discovery of Drought-Response Genes in Root Tissue Based on Transcriptomic Data.

PubMed

Tian, Xin-Jie; Long, Yan; Wang, Jiao; Zhang, Jing-Wen; Wang, Yan-Yan; Li, Wei-Min; Peng, Yu-Fa; Yuan, Qian-Hua; Pei, Xin-Wu

2015-01-01

The perennial O. rufipogon (common wild rice), which is considered to be the ancestor of Asian cultivated rice species, contains many useful genetic resources, including drought resistance genes. However, few studies have identified the drought resistance and tissue-specific genes in common wild rice. In this study, transcriptome sequencing libraries were constructed, including drought-treated roots (DR) and control leaves (CL) and roots (CR). Using Illumina sequencing technology, we generated 16.75 million bases of high-quality sequence data for common wild rice and conducted de novo assembly and annotation of genes without prior genome information. These reads were assembled into 119,332 unigenes with an average length of 715 bp. A total of 88,813 distinct sequences (74.42% of unigenes) significantly matched known genes in the NCBI NT database. Differentially expressed gene (DEG) analysis showed that 3617 genes were up-regulated and 4171 genes were down-regulated in the CR library compared with the CL library. Among the DEGs, 535 genes were expressed in roots but not in shoots. A similar comparison between the DR and CR libraries showed that 1393 genes were up-regulated and 315 genes were down-regulated in the DR library compared with the CR library. Finally, 37 genes that were specifically expressed in roots were screened after comparing the DEGs identified in the above-described analyses. This study provides a transcriptome sequence resource for common wild rice plants and establishes a digital gene expression profile of wild rice plants under drought conditions using the assembled transcriptome data as a reference. Several tissue-specific and drought-stress-related candidate genes were identified, representing a fully characterized transcriptome and providing a valuable resource for genetic and genomic studies in plants.

Model-based reconstruction of synthetic promoter library in Corynebacterium glutamicum.

PubMed

Zhang, Shuanghong; Liu, Dingyu; Mao, Zhitao; Mao, Yufeng; Ma, Hongwu; Chen, Tao; Zhao, Xueming; Wang, Zhiwen

2018-05-01

To develop an efficient synthetic promoter library for fine-tuned expression of target genes in Corynebacterium glutamicum. A synthetic promoter library for C. glutamicum was developed based on conserved sequences of the - 10 and - 35 regions. The synthetic promoter library covered a wide range of strengths, ranging from 1 to 193% of the tac promoter. 68 promoters were selected and sequenced for correlation analysis between promoter sequence and strength with a statistical model. A new promoter library was further reconstructed with improved promoter strength and coverage based on the results of correlation analysis. Tandem promoter P70 was finally constructed with increased strength by 121% over the tac promoter. The promoter library developed in this study showed a great potential for applications in metabolic engineering and synthetic biology for the optimization of metabolic networks. To the best of our knowledge, this is the first reconstruction of synthetic promoter library based on statistical analysis of C. glutamicum.

Programming gene expression with combinatorial promoters

PubMed Central

Cox, Robert Sidney; Surette, Michael G; Elowitz, Michael B

2007-01-01

Promoters control the expression of genes in response to one or more transcription factors (TFs). The architecture of a promoter is the arrangement and type of binding sites within it. To understand natural genetic circuits and to design promoters for synthetic biology, it is essential to understand the relationship between promoter function and architecture. We constructed a combinatorial library of random promoter architectures. We characterized 288 promoters in Escherichia coli, each containing up to three inputs from four different TFs. The library design allowed for multiple −10 and −35 boxes, and we observed varied promoter strength over five decades. To further analyze the functional repertoire, we defined a representation of promoter function in terms of regulatory range, logic type, and symmetry. Using these results, we identified heuristic rules for programming gene expression with combinatorial promoters. PMID:18004278

SAGE ANALYSIS OF TRANSCRIPTOME RESPONSES IN ARABIDOPSIS ROOTS EXPOSED TO 2,4,6-TRINITROTOLUENE

EPA Science Inventory

Serial Analysis of Gene Expression (SAGE) was used to profile transcript levels in Arabidopsis thaliana roots and assess their responses to 2,4,6-trinitrotoluene (TNT) exposure. SAGE libraries representing control and TNT-exposed seedling root transcripts were constructed, and ea...

Genetic Regulation in the Aiptasia pallida Symbiosis - Performance Report, Year 1.

DTIC Science & Technology

1997-02-01

and symbiotic zooxanthellae is one developed for serial analysis of gene expression (SAGE). We initially tested the SAGE protocol with cDNA generated...technically difficult. We are now focusing on constructing representative cDNA libraries from cultured and symbiotic zooxanthellae and will sequence

Nematicidal protease genes screened from a soil metagenomic library to control Radopholus similis mediated by Pseudomonas fluorescens pf36.

PubMed

Chen, Deqiang; Wang, Dongwei; Xu, Chunling; Chen, Chun; Li, Junyi; Wu, Wenjia; Huang, Xin; Xie, Hui

2018-04-01

Controlling Radopholus similis, an important phytopathogenic nematode, is a challenge worldwide. Herein, we constructed a metagenomic fosmid library from the rhizosphere soil of banana plants, and six clones with protease activity were obtained by functionally screening the library. Furthermore, subclones were constructed using the six clones, and three protease genes with nematicidal activity were identified: pase1, pase4, and pase6. The pase4 gene was successfully cloned and expressed, demonstrating that the protease PASE4 could effectively degrade R. similis tissues and result in nematode death. Additionally, we isolated a predominant R. similis-associated bacterium, Pseudomonas fluorescens (pf36), from 10 R. similis populations with different hosts. The pase4 gene was successfully introduced into the pf36 strain by vector transformation and conjugative transposition, and two genetically modified strains were obtained: p4MCS-pf36 and p4Tn5-pf36. p4MCS-pf36 had significantly higher protease expression and nematicidal activity (p < 0.05) than p4Tn5-pf36 in a microtiter plate assay, whereas p4Tn5-pf36 was superior to p4MCS-pf36 in terms of genetic stability and controlling R. similis in growth pot tests. This study confirmed that R. similis is inhibited by the associated bacterium pf36-mediated expression of nematicidal proteases. Herein, a novel approach is provided for the study and development of efficient, environmentally friendly, and sustainable biocontrol techniques against phytonematodes.

Heterologous viral expression systems in fosmid vectors increase the functional analysis potential of metagenomic libraries.

PubMed

Terrón-González, L; Medina, C; Limón-Mortés, M C; Santero, E

2013-01-01

The extraordinary potential of metagenomic functional analyses to identify activities of interest present in uncultured microorganisms has been limited by reduced gene expression in surrogate hosts. We have developed vectors and specialized E. coli strains as improved metagenomic DNA heterologous expression systems, taking advantage of viral components that prevent transcription termination at metagenomic terminators. One of the systems uses the phage T7 RNA-polymerase to drive metagenomic gene expression, while the other approach uses the lambda phage transcription anti-termination protein N to limit transcription termination. A metagenomic library was constructed and functionally screened to identify genes conferring carbenicillin resistance to E. coli. The use of these enhanced expression systems resulted in a 6-fold increase in the frequency of carbenicillin resistant clones. Subcloning and sequence analysis showed that, besides β-lactamases, efflux pumps are not only able contribute to carbenicillin resistance but may in fact be sufficient by themselves to convey carbenicillin resistance.

[Cloning, expression and characterization of a novel esterase from marine sediment microbial metagenomic library].

PubMed

Xu, Shiqing; Hu, Yongfei; Yuan, Aihua; Zhu, Baoli

2010-07-01

To clone, express and characterize a novel esterase from marine sediment microbial metagenomic library. Using esterase segregation agar containing tributyrin, we obtained esterase positive fosmid clone FL10 from marine sediment microbial metagenomic library. This fosmid was partially digested with Sau3A I to construct the sublibrary, from which the esterase positive subclone pFLS10 was obtained. The full length of the esterase gene was amplified and cloned into the expressing vector pET28a, and the recombinant plasmid was transformed into E. coli BL21 cells. We analyse the enzyme activity and study the characterization of the esterase after its expression and purification. An ORF (Open Reading Frame) of 924 bp was identified from the subclone pFLS10. Sequence analysis indicated that it showed 71% amino acid identity to esterase (ADA70030) from a marine sediment metagenomic library. The esterase is a novel low-temperature-active esterase and had highest lipolytic activity to the substrate of 4-nitrophenyl butyrate (C4). The optimum temperature of the esterase was 20 degrees C, the optimum pH was 7.5. The esterase in this study had good thermostability at 20 degrees C and good pH stability at pH8 -10. Significant increase in lipolytic activity was observed with addition of K+ and Mg2+, while decrease with Mn2+ etc. We obtained the novel esterase gene fls10 from the marine sediment microbial metagenomic library. The esterase had good thermostability and high lipolytic activity at low temperature and under basic conditions, which laid a basis for industrial application.

Construction and Evaluation of Normalized cDNA Libraries Enriched with Full-Length Sequences for Rapid Discovery of New Genes from Sisal (Agave sisalana Perr.) Different Developmental Stages

PubMed Central

Zhou, Wen-Zhao; Zhang, Yan-Mei; Lu, Jun-Ying; Li, Jun-Feng

2012-01-01

To provide a resource of sisal-specific expressed sequence data and facilitate this powerful approach in new gene research, the preparation of normalized cDNA libraries enriched with full-length sequences is necessary. Four libraries were produced with RNA pooled from Agave sisalana multiple tissues to increase efficiency of normalization and maximize the number of independent genes by SMART™ method and the duplex-specific nuclease (DSN). This procedure kept the proportion of full-length cDNAs in the subtracted/normalized libraries and dramatically enhanced the discovery of new genes. Sequencing of 3875 cDNA clones of libraries revealed 3320 unigenes with an average insert length about 1.2 kb, indicating that the non-redundancy of libraries was about 85.7%. These unigene functions were predicted by comparing their sequences to functional domain databases and extensively annotated with Gene Ontology (GO) terms. Comparative analysis of sisal unigenes and other plant genomes revealed that four putative MADS-box genes and knotted-like homeobox (knox) gene were obtained from a total of 1162 full-length transcripts. Furthermore, real-time PCR showed that the characteristics of their transcripts mainly depended on the tight expression regulation of a number of genes during the leaf and flower development. Analysis of individual library sequence data indicated that the pooled-tissue approach was highly effective in discovering new genes and preparing libraries for efficient deep sequencing. PMID:23202944

Isolation and expression of a Bacillus cereus gene encoding benzil reductase.

PubMed

Maruyama, R; Nishizawa, M; Itoi, Y; Ito, S; Inoue, M

2001-12-20

Benzil was reduced stereospecifically to (S)-benzoin by Bacillus cereus strain Tim-r01. To isolate the gene responsible for asymmetric reduction, we constructed a library consisting of Escherichia coli clones that harbored plasmids expressing Bacillus cereus genes. The library was screened using the halo formation assay, and one clone showed benzil reduction to (S)-benzoin. Thus, this clone seemed to carry a plasmid encoding a Bacillus cereus benzil reductase. The deduced amino acid sequence had marked homologies to the Bacillus subtilis yueD protein (41% identity), the yeast open reading frame YIR036C protein (31%), and the mammalian sepiapterin reductases (28% to 30%), suggesting that benzil reductase is a novel short-chain de-hydrogenases/ reductase. Copyright 2001 John Wiley & Sons, Inc.

Identifying differentially expressed genes in leaves of Glycine tomentella in the presence of the fungal pathogen Phakopsora pachyrhizi

USDA-ARS?s Scientific Manuscript database

Transcription profiles of Glycine tomentella genotypes having different responses to soybean rust, caused by the fungal pathogen Phakopsora pachyrhizi, were compared using suppression subtractive hybridization (SSH). Four cDNA libraries were constructed from infected and non-infected leaves of resis...

A Polymerase Chain Reaction-Based Method for Isolating Clones from a Complimentary DNA Library in Sheep

PubMed Central

Friis, Thor Einar; Stephenson, Sally; Xiao, Yin; Whitehead, Jon

2014-01-01

The sheep (Ovis aries) is favored by many musculoskeletal tissue engineering groups as a large animal model because of its docile temperament and ease of husbandry. The size and weight of sheep are comparable to humans, which allows for the use of implants and fixation devices used in human clinical practice. The construction of a complimentary DNA (cDNA) library can capture the expression of genes in both a tissue- and time-specific manner. cDNA libraries have been a consistent source of gene discovery ever since the technology became commonplace more than three decades ago. Here, we describe the construction of a cDNA library using cells derived from sheep bones based on the pBluescript cDNA kit. Thirty clones were picked at random and sequenced. This led to the identification of a novel gene, C12orf29, which our initial experiments indicate is involved in skeletal biology. We also describe a polymerase chain reaction-based cDNA clone isolation method that allows the isolation of genes of interest from a cDNA library pool. The techniques outlined here can be applied in-house by smaller tissue engineering groups to generate tools for biomolecular research for large preclinical animal studies and highlights the power of standard cDNA library protocols to uncover novel genes. PMID:24447069

Construction of a High-Quality Yeast Two-Hybrid Library and Its Application in Identification of Interacting Proteins with Brn1 in Curvularia lunata.

PubMed

Gao, Jin-Xin; Jing, Jing; Yu, Chuan-Jin; Chen, Jie

2015-06-01

Curvularia lunata is an important maize foliar fungal pathogen that distributes widely in maize growing area in China, and several key pathogenic factors have been isolated. An yeast two-hybrid (Y2H) library is a very useful platform to further unravel novel pathogenic factors in C. lunata. To construct a high-quality full length-expression cDNA library from the C. lunata for application to pathogenesis-related protein-protein interaction screening, total RNA was extracted. The SMART (Switching Mechanism At 5' end of the RNA Transcript) technique was used for cDNA synthesis. Double-stranded cDNA was ligated into the pGADT7-Rec vector with Herring Testes Carrier DNA using homologous recombination method. The ligation mixture was transformed into competent yeast AH109 cells to construct the primary cDNA library. Eventually, a high qualitative library was successfully established according to an evaluation on quality. The transformation efficiency was about 6.39 ×10(5) transformants/3 μg pGADT7-Rec. The titer of the primary cDNA library was 2.5×10(8) cfu/mL. The numbers for the cDNA library was 2.46×10(5). Randomly picked clones show that the recombination rate was 88.24%. Gel electrophoresis results indicated that the fragments ranged from 0.4 kb to 3.0 kb. Melanin synthesis protein Brn1 (1,3,8-hydroxynaphthalene reductase) was used as a "bait" to test the sufficiency of the Y2H library. As a result, a cDNA clone encoding VelB protein that was known to be involved in the regulation of diverse cellular processes, including control of secondary metabolism containing melanin and toxin production in many filamentous fungi was identified. Further study on the exact role of the VelB gene is underway.

Stability-Diversity Tradeoffs Impose Fundamental Constraints on Selection of Synthetic Human VH/VL Single-Domain Antibodies from In Vitro Display Libraries

PubMed Central

Henry, Kevin A.; Kim, Dae Young; Kandalaft, Hiba; Lowden, Michael J.; Yang, Qingling; Schrag, Joseph D.; Hussack, Greg; MacKenzie, C. Roger; Tanha, Jamshid

2017-01-01

Human autonomous VH/VL single-domain antibodies (sdAbs) are attractive therapeutic molecules, but often suffer from suboptimal stability, solubility and affinity for cognate antigens. Most commonly, human sdAbs have been isolated from in vitro display libraries constructed via synthetic randomization of rearranged VH/VL domains. Here, we describe the design and characterization of three novel human VH/VL sdAb libraries through a process of: (i) exhaustive biophysical characterization of 20 potential VH/VL sdAb library scaffolds, including assessment of expression yield, aggregation resistance, thermostability and tolerance to complementarity-determining region (CDR) substitutions; (ii) in vitro randomization of the CDRs of three VH/VL sdAb scaffolds, with tailored amino acid representation designed to promote solubility and expressibility; and (iii) systematic benchmarking of the three VH/VL libraries by panning against five model antigens. We isolated ≥1 antigen-specific human sdAb against four of five targets (13 VHs and 7 VLs in total); these were predominantly monomeric, had antigen-binding affinities ranging from 5 nM to 12 µM (average: 2–3 µM), but had highly variable expression yields (range: 0.1–19 mg/L). Despite our efforts to identify the most stable VH/VL scaffolds, selection of antigen-specific binders from these libraries was unpredictable (overall success rate for all library-target screens: ~53%) with a high attrition rate of sdAbs exhibiting false positive binding by ELISA. By analyzing VH/VL sdAb library sequence composition following selection for monomeric antibody expression (binding to protein A/L followed by amplification in bacterial cells), we found that some VH/VL sdAbs had marked growth advantages over others, and that the amino acid composition of the CDRs of this set of sdAbs was dramatically restricted (bias toward Asp and His and away from aromatic and hydrophobic residues). Thus, CDR sequence clearly dramatically impacts the stability of human autonomous VH/VL immunoglobulin domain folds, and sequence-stability tradeoffs must be taken into account during the design of such libraries. PMID:29375542

The construction of cDNA library and the screening of related antigen of ascitic tumor cells of ovarian cancer.

PubMed

Hou, Q; Chen, K; Shan, Z

2015-01-01

To construct the cDNA library of the ascites tumor cells of ovarian cancer, which can be used to screen the related antigen for the early diagnosis of ovarian cancer and therapeutic targets of immune treatment. Four cases of ovarian serous cystadenocarcinoma, two cases of ovarian mucinous cystadenocarcinoma, and two cases of ovarian endometrial carcinoma in patients with ascitic tumor cells which were used to construct the cDNA library. To screen the ovarian cancer antigen gene, evaluate the enzyme, and analyze nucleotide sequence, serological analysis of recombinant tumor cDNA expression libraries (SEREX) and suppression subtractive hybridization technique (SSH) techniques were utilized. The detection method of recombinant expression-based serological mini-arrays (SMARTA) was used to detect the ovarian cancer antigen and the positive reaction of 105 cases of ovarian cancer patients and 105 normal women's autoantibodies correspondingly in serum. After two rounds of serologic screening and glycosides sequencing analysis, 59 candidates of ovarian cancer antigen gene fragments were finally identified, which corresponded to 50 genes. They were then divided into six categories: (1) the homologous genes which related to the known ovarian cancer genes, such as BARD 1 gene, etc; (2) the homologous genes which were associated with other tumors, such as TM4SFI gene, etc; (3) the genes which were expressed in a special organization, such as ILF3, FXR1 gene, etc; (4) the genes which were the same with some protein genes of special function, such as TIZ, ClD gene; (5) the homologous genes which possessed the same source with embryonic genes, such as PKHD1 gene, etc; (6) the remaining genes were the unknown genes without the homologous sequence in the gene pool, such as OV-189 genes. SEREX technology combined with SSH method is an effective research strategy which can filter tumor antigen with high specific character; the corresponding autoantibodies of TM4SFl, ClD, TIZ, BARDI, FXRI, and OV-189 gene's recombinant antigen in serum can be regarded as the biomarkers which are used to diagnose ovarian cancer. The combination of multiple antigen detection can improve diagnostic efficiency.

BrAD-seq: Breath Adapter Directional sequencing: a streamlined, ultra-simple and fast library preparation protocol for strand specific mRNA library construction.

PubMed

Townsley, Brad T; Covington, Michael F; Ichihashi, Yasunori; Zumstein, Kristina; Sinha, Neelima R

2015-01-01

Next Generation Sequencing (NGS) is driving rapid advancement in biological understanding and RNA-sequencing (RNA-seq) has become an indispensable tool for biology and medicine. There is a growing need for access to these technologies although preparation of NGS libraries remains a bottleneck to wider adoption. Here we report a novel method for the production of strand specific RNA-seq libraries utilizing the terminal breathing of double-stranded cDNA to capture and incorporate a sequencing adapter. Breath Adapter Directional sequencing (BrAD-seq) reduces sample handling and requires far fewer enzymatic steps than most available methods to produce high quality strand-specific RNA-seq libraries. The method we present is optimized for 3-prime Digital Gene Expression (DGE) libraries and can easily extend to full transcript coverage shotgun (SHO) type strand-specific libraries and is modularized to accommodate a diversity of RNA and DNA input materials. BrAD-seq offers a highly streamlined and inexpensive option for RNA-seq libraries.

MISSION LentiPlex pooled shRNA library screening in mammalian cells.

PubMed

Coussens, Matthew J; Corman, Courtney; Fischer, Ashley L; Sago, Jack; Swarthout, John

2011-12-21

RNA interference (RNAi) is an intrinsic cellular mechanism for the regulation of gene expression. Harnessing the innate power of this system enables us to knockdown gene expression levels in loss of gene function studies. There are two main methods for performing RNAi. The first is the use of small interfering RNAs (siRNAs) that are chemically synthesized, and the second utilizes short-hairpin RNAs (shRNAs) encoded within plasmids. The latter can be transfected into cells directly or packaged into replication incompetent lentiviral particles. The main advantages of using lentiviral shRNAs is the ease of introduction into a wide variety of cell types, their ability to stably integrate into the genome for long term gene knockdown and selection, and their efficacy in conducting high-throughput loss of function screens. To facilitate this we have created the LentiPlex pooled shRNA library. The MISSION LentiPlex Human shRNA Pooled Library is a genome-wide lentiviral pool produced using a proprietary process. The library consists of over 75,000 shRNA constructs from the TRC collection targeting 15,000+ human genes. Each library is tested for shRNA representation before product release to ensure robust library coverage. The library is provided in a ready-to-use lentiviral format at titers of at least 5 x 10(8) TU/ml via p24 assay and is pre-divided into ten subpools of approximately 8,000 shRNA constructs each. Amplification and sequencing primers are also provided for downstream target identification. Previous studies established a synergistic antitumor activity of TRAIL when combined with Paclitaxel in A549 cells, a human lung carcinoma cell line. In this study we demonstrate the application of a pooled LentiPlex shRNA library to rapidly conduct a positive selection screen for genes involved in the cytotoxicity of A549 cells when exposed to TRAIL and Paclitaxel. One barrier often encountered with high-throughput screens is the cost and difficulty in deconvolution; we also detail a cost-effective polyclonal approach utilizing traditional sequencing.

The carnegie protein trap library: a versatile tool for Drosophila developmental studies.

PubMed

Buszczak, Michael; Paterno, Shelley; Lighthouse, Daniel; Bachman, Julia; Planck, Jamie; Owen, Stephenie; Skora, Andrew D; Nystul, Todd G; Ohlstein, Benjamin; Allen, Anna; Wilhelm, James E; Murphy, Terence D; Levis, Robert W; Matunis, Erika; Srivali, Nahathai; Hoskins, Roger A; Spradling, Allan C

2007-03-01

Metazoan physiology depends on intricate patterns of gene expression that remain poorly known. Using transposon mutagenesis in Drosophila, we constructed a library of 7404 protein trap and enhancer trap lines, the Carnegie collection, to facilitate gene expression mapping at single-cell resolution. By sequencing the genomic insertion sites, determining splicing patterns downstream of the enhanced green fluorescent protein (EGFP) exon, and analyzing expression patterns in the ovary and salivary gland, we found that 600-900 different genes are trapped in our collection. A core set of 244 lines trapped different identifiable protein isoforms, while insertions likely to act as GFP-enhancer traps were found in 256 additional genes. At least 8 novel genes were also identified. Our results demonstrate that the Carnegie collection will be useful as a discovery tool in diverse areas of cell and developmental biology and suggest new strategies for greatly increasing the coverage of the Drosophila proteome with protein trap insertions.

Cloning, annotation and expression analysis of mycoparasitism-related genes in Trichoderma harzianum 88.

PubMed

Yao, Lin; Yang, Qian; Song, Jinzhu; Tan, Chong; Guo, Changhong; Wang, Li; Qu, Lianhai; Wang, Yun

2013-04-01

Trichoderma harzianum 88, a filamentous soil fungus, is an effective biocontrol agent against several plant pathogens. High-throughput sequencing was used here to study the mycoparasitism mechanisms of T. harzianum 88. Plate confrontation tests of T. harzianum 88 against plant pathogens were conducted, and a cDNA library was constructed from T. harzianum 88 mycelia in the presence of plant pathogen cell walls. Randomly selected transcripts from the cDNA library were compared with eukaryotic plant and fungal genomes. Of the 1,386 transcripts sequenced, the most abundant Gene Ontology (GO) classification group was "physiological process". Differential expression of 19 genes was confirmed by real-time RT-PCR at different mycoparasitism stages against plant pathogens. Gene expression analysis revealed the transcription of various genes involved in mycoparasitism of T. harzianum 88. Our study provides helpful insights into the mechanisms of T. harzianum 88-plant pathogen interactions.

Construction of a full-length cDNA Library from Chinese oak silkworm pupa and identification of a KK-42-binding protein gene in relation to pupa-diapause termination.

PubMed

Li, Yu-Ping; Xia, Run-Xi; Wang, Huan; Li, Xi-Sheng; Liu, Yan-Qun; Wei, Zhao-Jun; Lu, Cheng; Xiang, Zhong-Huai

2009-06-24

In this study we successfully constructed a full-length cDNA library from Chinese oak silkworm, Antheraea pernyi, the most well-known wild silkworm used for silk production and insect food. Total RNA was extracted from a single fresh female pupa at the diapause stage. The titer of the library was 5 x 10(5) cfu/ml and the proportion of recombinant clones was approximately 95%. Expressed sequence tag (EST) analysis was used to characterize the library. A total of 175 clustered ESTs consisting of 24 contigs and 151 singlets were generated from 250 effective sequences. Of the 175 unigenes, 97 (55.4%) were known genes but only five from A. pernyi, 37 (21.2%) were known ESTs without function annotation, and 41 (23.4%) were novel ESTs. By EST sequencing, a gene coding KK-42-binding protein in A. pernyi (named as ApKK42-BP; GenBank accession no. FJ744151) was identified and characterized. Protein sequence analysis showed that ApKK42-BP was not a membrane protein but an extracellular protein with a signal peptide at position 1-18, and contained two putative conserved domains, abhydro_lipase and abhydrolase_1, suggesting it may be a member of lipase superfamily. Expression analysis based on number of ESTs showed that ApKK42-BP was an abundant gene in the period of diapause stage, suggesting it may also be involved in pupa-diapause termination.

Construction of a full-length cDNA Library from Chinese oak silkworm pupa and identification of a KK-42-binding protein gene in relation to pupa-diapause termination

PubMed Central

Li, Yu-Ping; Xia, Run-Xi; Wang, Huan; Li, Xi-Sheng; Liu, Yan-Qun; Wei, Zhao-Jun; Lu, Cheng; Xiang, Zhong-Huai

2009-01-01

In this study we successfully constructed a full-length cDNA library from Chinese oak silkworm, Antheraea pernyi, the most well-known wild silkworm used for silk production and insect food. Total RNA was extracted from a single fresh female pupa at the diapause stage. The titer of the library was 5 × 105 cfu/ml and the proportion of recombinant clones was approximately 95%. Expressed sequence tag (EST) analysis was used to characterize the library. A total of 175 clustered ESTs consisting of 24 contigs and 151 singlets were generated from 250 effective sequences. Of the 175 unigenes, 97 (55.4%) were known genes but only five from A. pernyi, 37 (21.2%) were known ESTs without function annotation, and 41 (23.4%) were novel ESTs. By EST sequencing, a gene coding KK-42-binding protein in A. pernyi (named as ApKK42-BP; GenBank accession no. FJ744151) was identified and characterized. Protein sequence analysis showed that ApKK42-BP was not a membrane protein but an extracellular protein with a signal peptide at position 1-18, and contained two putative conserved domains, abhydro_lipase and abhydrolase_1, suggesting it may be a member of lipase superfamily. Expression analysis based on number of ESTs showed that ApKK42-BP was an abundant gene in the period of diapause stage, suggesting it may also be involved in pupa-diapause termination. PMID:19564928

Comprehensive transcriptome profiling reveals long noncoding RNA expression and alternative splicing regulation during fruit development and ripening in kiwifruit (Actinidia chinensis)

USDA-ARS?s Scientific Manuscript database

Genomic and transcriptomic data on kiwifruit (Actinidia chinensis) in public databases are very limited despite its nutritional and economic value. Previously, we have constructed and sequenced nine fruit RNA-Seq libraries of A. chinensis cv. 'Hongyang' at immature, mature, and postharvest ripening...

Characterization and expression analysis of a banana gene encoding 1-aminocyclopropane-1-carboxylate oxidase.

PubMed

Huang, P L; Do, Y Y; Huang, F C; Thay, T S; Chang, T W

1997-04-01

A cDNA encoding the banana 1-aminocyclopropane-1-carboxylate (ACC) oxidase has previously been isolated from a cDNA library that was constructed by extracting poly(A)+ RNA from peels of ripening banana. This cDNA, designated as pMAO2, has 1,199 bp and contains an open reading frame of 318 amino acids. In order to identify ripening-related promoters of the banana ACC oxidase gene, pMAO2 was used as a probe to screen a banana genomic library constructed in the lambda EMBL3 vector. The banana ACC oxidase MAO2 gene has four exons and three introns, with all of the boundaries between these introns and exons sharing a consensus dinucleotide sequence of GT-AG. The expression of MAO2 gene in banana begins after the onset of ripening (stage 2) and continuous into later stages of the ripening process. The accumulation of MAO2 mRNA can be induced by 1 microliter/l exogenous ethylene, and it reached steady state level when 100 microliters/l exogenous ethylene was present.

Genomics approach to the environmental community of microorganisms

NASA Astrophysics Data System (ADS)

Kawarabayasi, Y.; Maruyama, A.

2004-12-01

It was indicated by microscopic observation or comparison of 16S rDNA sequence that many extremophiles were surviving in many hydrothermal environments. But it is generally said that over 99% of total microbes are now uncultivable. Thus, we planned to identify uncultivable microbes through direct sequencing of environmental DNA. At first, shotgun plasmid libraries were directly constructed with the DNA molecules prepared from mixed microbes collected from low-temperature hydrothermal water at RM24 in the Southern East Pacific Rise (S-EPR). It was shown that the sequences of some number of clones indicated the similar feature to the intron in eukaryote or tandem repetitive sequence identified in some human familiar diseases. The results indicated that many microorganisms with eukaryotic feature were dominant in low temperature water of S-EPR. Secondly, shotgun plasmid libraries were constructed from the environmental DNA prepared from Beppu hot springs. The ORFs were easily identified all clones determined entire sequence. Thus it can be said that hot springs is good resources for searching novel genes. At last, the mixed microbes isolated from Suiyo seamount were used for construction of shotgun library. The clones in this library contained the ORFs. From some clones in hot spring and Suiyo sample, aminoacyl-tRNA synthatase, which is generally present in all organisms, was isolated by similarity. The phylogenetic analysis of aminoacyl-tRNA synthetase identified indicated that novel and unidentified microorganisms should be present in hot spring or Suiyo seamount. The novel genes identified from Suiyo seamount were also utilized for expression in E. coli. Some gene products were successfully obtained from the E. coli cells as soluble proteins. Some protein indicated the thermostability up to 70_E#8249;C, meaning that the original host cell of this gene should be stable up to the same temperature. Our work indicates that environmental genomics, including the direct cloning, sequencing of environmental DNA and expression of gene identified, is powerful approach to collect novel uncultivable microbes or novel active genes.

Construction of a Full-Length Enriched cDNA Library and Preliminary Analysis of Expressed Sequence Tags from Bengal Tiger Panthera tigris tigris

PubMed Central

Liu, Changqing; Liu, Dan; Guo, Yu; Lu, Taofeng; Li, Xiangchen; Zhang, Minghai; Ma, Jianzhang; Ma, Yuehui; Guan, Weijun

2013-01-01

In this study, a full-length enriched cDNA library was successfully constructed from Bengal tiger, Panthera tigris tigris, the most well-known wild Animal. Total RNA was extracted from cultured Bengal tiger fibroblasts in vitro. The titers of primary and amplified libraries were 1.28 × 106 pfu/mL and 1.56 × 109 pfu/mL respectively. The percentage of recombinants from unamplified library was 90.2% and average length of exogenous inserts was 0.98 kb. A total of 212 individual ESTs with sizes ranging from 356 to 1108 bps were then analyzed. The BLASTX score revealed that 48.1% of the sequences were classified as a strong match, 45.3% as nominal and 6.6% as a weak match. Among the ESTs with known putative function, 26.4% ESTs were found to be related to all kinds of metabolisms, 19.3% ESTs to information storage and processing, 11.3% ESTs to posttranslational modification, protein turnover, chaperones, 11.3% ESTs to transport, 9.9% ESTs to signal transducer/cell communication, 9.0% ESTs to structure protein, 3.8% ESTs to cell cycle, and only 6.6% ESTs classified as novel genes. By EST sequencing, a full-length gene coding ferritin was identified and characterized. The recombinant plasmid pET32a-TAT-Ferritin was constructed, coded for the TAT-Ferritin fusion protein with two 6× His-tags in N and C-terminal. After BCA assay, the concentration of soluble Trx-TAT-Ferritin recombinant protein was 2.32 ± 0.12 mg/mL. These results demonstrated that the reliability and representativeness of the cDNA library attained to the requirements of a standard cDNA library. This library provided a useful platform for the functional genome and transcriptome research of Bengal tigers. PMID:23708105

Construction of a full-length enriched cDNA library and preliminary analysis of expressed sequence tags from Bengal Tiger Panthera tigris tigris.

PubMed

Liu, Changqing; Liu, Dan; Guo, Yu; Lu, Taofeng; Li, Xiangchen; Zhang, Minghai; Ma, Jianzhang; Ma, Yuehui; Guan, Weijun

2013-05-24

In this study, a full-length enriched cDNA library was successfully constructed from Bengal tiger, Panthera tigris tigris, the most well-known wild Animal. Total RNA was extracted from cultured Bengal tiger fibroblasts in vitro. The titers of primary and amplified libraries were 1.28 × 106 pfu/mL and 1.56 × 109 pfu/mL respectively. The percentage of recombinants from unamplified library was 90.2% and average length of exogenous inserts was 0.98 kb. A total of 212 individual ESTs with sizes ranging from 356 to 1108 bps were then analyzed. The BLASTX score revealed that 48.1% of the sequences were classified as a strong match, 45.3% as nominal and 6.6% as a weak match. Among the ESTs with known putative function, 26.4% ESTs were found to be related to all kinds of metabolisms, 19.3% ESTs to information storage and processing, 11.3% ESTs to posttranslational modification, protein turnover, chaperones, 11.3% ESTs to transport, 9.9% ESTs to signal transducer/cell communication, 9.0% ESTs to structure protein, 3.8% ESTs to cell cycle, and only 6.6% ESTs classified as novel genes. By EST sequencing, a full-length gene coding ferritin was identified and characterized. The recombinant plasmid pET32a-TAT-Ferritin was constructed, coded for the TAT-Ferritin fusion protein with two 6× His-tags in N and C-terminal. After BCA assay, the concentration of soluble Trx-TAT-Ferritin recombinant protein was 2.32 ± 0.12 mg/mL. These results demonstrated that the reliability and representativeness of the cDNA library attained to the requirements of a standard cDNA library. This library provided a useful platform for the functional genome and transcriptome research of Bengal tigers.

MytiBase: a knowledgebase of mussel (M. galloprovincialis) transcribed sequences

PubMed Central

Venier, Paola; De Pittà, Cristiano; Bernante, Filippo; Varotto, Laura; De Nardi, Barbara; Bovo, Giuseppe; Roch, Philippe; Novoa, Beatriz; Figueras, Antonio; Pallavicini, Alberto; Lanfranchi, Gerolamo

2009-01-01

Background Although Bivalves are among the most studied marine organisms due to their ecological role, economic importance and use in pollution biomonitoring, very little information is available on the genome sequences of mussels. This study reports the functional analysis of a large-scale Expressed Sequence Tag (EST) sequencing from different tissues of Mytilus galloprovincialis (the Mediterranean mussel) challenged with toxic pollutants, temperature and potentially pathogenic bacteria. Results We have constructed and sequenced seventeen cDNA libraries from different Mediterranean mussel tissues: gills, digestive gland, foot, anterior and posterior adductor muscle, mantle and haemocytes. A total of 24,939 clones were sequenced from these libraries generating 18,788 high-quality ESTs which were assembled into 2,446 overlapping clusters and 4,666 singletons resulting in a total of 7,112 non-redundant sequences. In particular, a high-quality normalized cDNA library (Nor01) was constructed as determined by the high rate of gene discovery (65.6%). Bioinformatic screening of the non-redundant M. galloprovincialis sequences identified 159 microsatellite-containing ESTs. Clusters, consensuses, related similarities and gene ontology searches have been organized in a dedicated, searchable database . Conclusion We defined the first species-specific catalogue of M. galloprovincialis ESTs including 7,112 unique transcribed sequences. Putative microsatellite markers were identified. This annotated catalogue represents a valuable platform for expression studies, marker validation and genetic linkage analysis for investigations in the biology of Mediterranean mussels. PMID:19203376

Identification of antigens by monoclonal antibody PD4 and its expression in Escherichia coli

PubMed Central

Ning, Jin-Ying; Sun, Guo-Xun; Huang, Su; Ma, Hong; An, Ping; Meng, Lin; Song, Shu-Mei; Wu, Jian; Shou, Cheng-Chao

2003-01-01

AIM: To clone and express the antigen of monoclonal antibody (MAb) PD4 for further investigation of its function. METHODS: MGC803 cDNA expression library was constructed and screened with PD4 as probes to clone the antigen. After failed in the library screening, immunoprecipitation and SDS-polyacrylamide gel electrophoresis were applied to purify the antigen for sequence analysis. The antigen coming from Mycoplasma hyorhinis (M. hyorhinis) was further confirmed with Western blot analysis by infecting M. hyorhinis -free HeLa cells and eliminating the M. hyorhinis from MGC803 cells. The full p37 gene was cloned by PCR and expressed successfully in Escherichia coli after site-directed mutations. Immunofluorescence assay was used to demonstrate if p37 protein could directly bind to gastric tumor cell AGS. RESULTS: The cDNA library constructed with MGC803 cells was screened by MAb PD4 as probes. Unfortunately, the positive clones identified with MAb PD4 were also reacted with unrelated antibodies. Then, immunoprecipitation was performed and the purified antigen was identified to be a membrane protein of Mycoplasma hyorhinis (M. hyorhinis) by sequencing of N-terminal amino acid residues. The membrane protein was intensively verified with Western blot by eliminating M. hyorhinis from MGC803 cells and by infecting M. hyorhinis-free HeLa cells. The full p37 gene was cloned and expressed successfully in Escherichia coli after site-directed mutations. Immunofluorescence demonstrated that p37 protein could directly bind to gastric tumor cell AGS. CONCLUSION: The antigen recognized by MAb PD4 is from M. hyorhinis, which suggests the actions involved in MAb PD4 is possibly mediated by p37 protein or M. hyorhinis. As p37 protein can bind directly to tumor cells, the pathogenic role of p37 involved in tumorigenesis justifies further investigation. PMID:14562370

Construction of a complementary DNA library for Parelaphostrongylus tenuis and identification of a potentially sero-diagnostic recombinant antigen.

PubMed

Ogunremi, Oladele; Benjamin, Jane; MacDonald, Lily; Schimpf, Robert

2008-12-01

Newly developed serological tests for diagnosing parelaphostrongylosis in cervids, using the excretory-secretory products (ES) of the infective larvae of Parelaphostrongylus tenuis in enzyme-linked immunosorbent assays (ELISAs), have demonstrable superiority over the traditional method of larval recovery and microscopic identification. To generate a source of ELISA antigen by genetic engineering, we created a complementary DNA (cDNA) expression library by the reverse transcription of mRNA of P. tenuis adult worms, and ligation with the vector lambda-ZAP II. The library was screened using antisera produced in mice by immunization with a somatic antigen preparation of adult worms. Seventeen clones were isolated, sequenced, and checked for similarity to other DNA sequences in GenBank. A previously identified parasite gene encoding an aspartyl protease inhibitor (API) was isolated from the cDNA library, subcloned and expressed using the pET expression vector to produce a glutathione S transferase (GST)-His-S.Tag-P. tenuis API fusion protein (molecular weight = 63 kDa). An enzyme-linked immunosorbent assay utilizing the API fusion protein as the coating antigen was used to serologically diagnose all white-tailed deer (WTD, 10 out of 10) that had been inoculated with 6 - 150 L3 P. tenuis, indicating that the antigen may be a useful serodiagnostic antigen for P. tenuis infection in this cervid species.

Rule-Based Design of Plant Expression Vectors Using GenoCAD.

PubMed

Coll, Anna; Wilson, Mandy L; Gruden, Kristina; Peccoud, Jean

2015-01-01

Plant synthetic biology requires software tools to assist on the design of complex multi-genic expression plasmids. Here a vector design strategy to express genes in plants is formalized and implemented as a grammar in GenoCAD, a Computer-Aided Design software for synthetic biology. It includes a library of plant biological parts organized in structural categories and a set of rules describing how to assemble these parts into large constructs. Rules developed here are organized and divided into three main subsections according to the aim of the final construct: protein localization studies, promoter analysis and protein-protein interaction experiments. The GenoCAD plant grammar guides the user through the design while allowing users to customize vectors according to their needs. Therefore the plant grammar implemented in GenoCAD will help plant biologists take advantage of methods from synthetic biology to design expression vectors supporting their research projects.

Quantifying and resolving multiple vector transformants in S. cerevisiae plasmid libraries.

PubMed

Scanlon, Thomas C; Gray, Elizabeth C; Griswold, Karl E

2009-11-20

In addition to providing the molecular machinery for transcription and translation, recombinant microbial expression hosts maintain the critical genotype-phenotype link that is essential for high throughput screening and recovery of proteins encoded by plasmid libraries. It is known that Escherichia coli cells can be simultaneously transformed with multiple unique plasmids and thusly complicate recombinant library screening experiments. As a result of their potential to yield misleading results, bacterial multiple vector transformants have been thoroughly characterized in previous model studies. In contrast to bacterial systems, there is little quantitative information available regarding multiple vector transformants in yeast. Saccharomyces cerevisiae is the most widely used eukaryotic platform for cell surface display, combinatorial protein engineering, and other recombinant library screens. In order to characterize the extent and nature of multiple vector transformants in this important host, plasmid-born gene libraries constructed by yeast homologous recombination were analyzed by DNA sequencing. It was found that up to 90% of clones in yeast homologous recombination libraries may be multiple vector transformants, that on average these clones bear four or more unique mutant genes, and that these multiple vector cells persist as a significant proportion of library populations for greater than 24 hours during liquid outgrowth. Both vector concentration and vector to insert ratio influenced the library proportion of multiple vector transformants, but their population frequency was independent of transformation efficiency. Interestingly, the average number of plasmids born by multiple vector transformants did not vary with their library population proportion. These results highlight the potential for multiple vector transformants to dominate yeast libraries constructed by homologous recombination. The previously unrecognized prevalence and persistence of multiply transformed yeast cells have important implications for yeast library screens. The quantitative information described herein should increase awareness of this issue, and the rapid sequencing approach developed for these studies should be widely useful for identifying multiple vector transformants and avoiding complications associated with cells that have acquired more than one unique plasmid.

Gene Expression Differences in Infected and Noninfected Middle Ear Complementary DNA Libraries

PubMed Central

Kerschner, Joseph E.; Horsey, Edward; Ahmed, Azad; Erbe, Christy; Khampang, Pawjai; Cioffi, Joseph; Hu, Fen Ze; Post, James Christopher; Ehrlich, Garth D.

2010-01-01

Objectives To investigate genetic differences in middle ear mucosa (MEM) with nontypeable Haemophilus influenzae (NTHi) infection. Genetic upregulation and downregulation occurs in MEM during otitis media (OM) pathogenesis. A comprehensive assessment of these genetic differences using the techniques of complementary DNA (cDNA) library creation has not been performed. Design The cDNA libraries were constructed from NTHi-infected and noninfected chinchilla MEM. Random clones were picked, sequenced bidirectionally, and submitted to the National Center for Biotechnology Information (NCBI) Expressed Sequence Tags database, where they were assigned accession numbers. These numbers were used with the basic local alignment search tool (BLAST) to align clones against the nonredundant nucleotide database at NCBI. Results Analysis with the Web-based statistical program FatiGO identified several biological processes with significant differences in numbers of represented genes. Processes involved in immune, stress, and wound responses were more prevalent in the NTHi-infected library. S100 calcium-binding protein A9 (S100A9); secretory leukoprotease inhibitor (SLPI); β2-microglobulin (B2M); ferritin, heavy-chain polypeptide 1 (FTH1); and S100 calcium-binding protein A8 (S100A8) were expressed at significantly higher levels in the NTHi-infected library. Calcium-binding proteins S100A9 and S100A8 serve as markers for inflammation and have antibacterial effects. Secretory leukoprotease inhibitor is an antibacterial protein that inhibits stimuli-induced MUC1, MUC2, and MUC5AC production. Conclusions A number of genes demonstrate changes during the pathogenesis of OM, including SLPI, which has an impact on mucin gene expression; this expression is known to be an important regulator in OM. The techniques described herein provide a framework for future investigations to more thoroughly understand molecular changes in the middle ear, which will likely be important in developing new therapeutic and intervention strategies. PMID:19153305

Construction and analysis of cDNA libraries from the antennae of Batocera horsfieldi and expression pattern of putative odorant binding proteins

USDA-ARS?s Scientific Manuscript database

In the natural environment, the longhorned beetle, Batocera horsfieldi (Hope) (Coleoptera: Cerambycidae), finds it’s maturation-feeding and host plants by using chemical cues. In this study, we described the identification and characterization of four new cDNAs that encode Minus-C odorant binding pr...

Expressed sequence tag analysis of adult human optic nerve for NEIBank: Identification of cell type and tissue markers

PubMed Central

Bernstein, Steven L; Guo, Yan; Peterson, Katherine; Wistow, Graeme

2009-01-01

Background The optic nerve is a pure white matter central nervous system (CNS) tract with an isolated blood supply, and is widely used in physiological studies of white matter response to various insults. We examined the gene expression profile of human optic nerve (ON) and, through the NEIBANK online resource, to provide a resource of sequenced verified cDNA clones. An un-normalized cDNA library was constructed from pooled human ON tissues and was used in expressed sequence tag (EST) analysis. Location of an abundant oligodendrocyte marker was examined by immunofluorescence. Quantitative real time polymerase chain reaction (qRT-PCR) and Western analysis were used to compare levels of expression for key calcium channel protein genes and protein product in primate and rodent ON. Results Our analyses revealed a profile similar in many respects to other white matter related tissues, but significantly different from previously available ON cDNA libraries. The previous libraries were found to include specific markers for other eye tissues, suggesting contamination. Immune/inflammatory markers were abundant in the new ON library. The oligodendrocyte marker QKI was abundant at the EST level. Immunofluorescence revealed that this protein is a useful oligodendrocyte cell-type marker in rodent and primate ONs. L-type calcium channel EST abundance was found to be particularly low. A qRT-PCR-based comparative mammalian species analysis reveals that L-type calcium channel expression levels are significantly lower in primate than in rodent ON, which may help account for the class-specific difference in responsiveness to calcium channel blocking agents. Several known eye disease genes are abundantly expressed in ON. Many genes associated with normal axonal function, mRNAs associated with axonal transport, inflammation and neuroprotection are observed. Conclusion We conclude that the new cDNA library is a faithful representation of human ON and EST data provide an initial overview of gene expression patterns in this tissue. The data provide clues for tissue-specific and species-specific properties of human ON that will help in design of therapeutic models. PMID:19778450

Stability-Diversity Tradeoffs Impose Fundamental Constraints on Selection of Synthetic Human VH/VL Single-Domain Antibodies from In Vitro Display Libraries.

PubMed

Henry, Kevin A; Kim, Dae Young; Kandalaft, Hiba; Lowden, Michael J; Yang, Qingling; Schrag, Joseph D; Hussack, Greg; MacKenzie, C Roger; Tanha, Jamshid

2017-01-01

Human autonomous V H /V L single-domain antibodies (sdAbs) are attractive therapeutic molecules, but often suffer from suboptimal stability, solubility and affinity for cognate antigens. Most commonly, human sdAbs have been isolated from in vitro display libraries constructed via synthetic randomization of rearranged V H /V L domains. Here, we describe the design and characterization of three novel human V H /V L sdAb libraries through a process of: (i) exhaustive biophysical characterization of 20 potential V H /V L sdAb library scaffolds, including assessment of expression yield, aggregation resistance, thermostability and tolerance to complementarity-determining region (CDR) substitutions; (ii) in vitro randomization of the CDRs of three V H /V L sdAb scaffolds, with tailored amino acid representation designed to promote solubility and expressibility; and (iii) systematic benchmarking of the three V H /V L libraries by panning against five model antigens. We isolated ≥1 antigen-specific human sdAb against four of five targets (13 V H s and 7 V L s in total); these were predominantly monomeric, had antigen-binding affinities ranging from 5 nM to 12 µM (average: 2-3 µM), but had highly variable expression yields (range: 0.1-19 mg/L). Despite our efforts to identify the most stable V H /V L scaffolds, selection of antigen-specific binders from these libraries was unpredictable (overall success rate for all library-target screens: ~53%) with a high attrition rate of sdAbs exhibiting false positive binding by ELISA. By analyzing V H /V L sdAb library sequence composition following selection for monomeric antibody expression (binding to protein A/L followed by amplification in bacterial cells), we found that some V H /V L sdAbs had marked growth advantages over others, and that the amino acid composition of the CDRs of this set of sdAbs was dramatically restricted (bias toward Asp and His and away from aromatic and hydrophobic residues). Thus, CDR sequence clearly dramatically impacts the stability of human autonomous V H /V L immunoglobulin domain folds, and sequence-stability tradeoffs must be taken into account during the design of such libraries.

Comparative Analysis of Expressed Genes from Cacao Meristems Infected by Moniliophthora perniciosa

PubMed Central

Gesteira, Abelmon S.; Micheli, Fabienne; Carels, Nicolas; Da Silva, Aline C.; Gramacho, Karina P.; Schuster, Ivan; Macêdo, Joci N.; Pereira, Gonçalo A. G.; Cascardo, Júlio C. M.

2007-01-01

Background and Aims Witches' broom disease is caused by the hemibiotrophic basidiomycete Moniliophthora perniciosa, and is one of the most important diseases of cacao in the western hemisphere. Because very little is known about the global process of such disease development, expressed sequence tags (ESTs) were used to identify genes expressed during the Theobroma cacao–Moniliophthora perniciosa interaction. Methods Two cDNA libraries corresponding to the resistant (RT) and susceptible (SP) cacao–M. perniciosa interactions were constructed from total RNA, using the DB SMART Creator cDNA library kit (Clontech). Clones were randomly selected, sequenced from the 5′ end and analysed using bioinformatics tools including in silico analysis of the differential gene expression. Key Results A total of 6884 ESTs were generated from the RT and SP cDNA libraries. These ESTs were composed of 2585 singlets and 341 contigs for a total of 2926 non-redundant sequences. The redundancy of the libraries was low and their specificity high when compared with the few other cacao libraries already published. Sequence analysis allowed the assignment of a putative functional category for 54 % of sequences, whereas approx. 22 % of sequences corresponded to unknown function and approx. 24 % of sequences did not show any significant similarity with other proteins present in the database. Despite the similar overall distribution of the sequences in functional categories between the two libraries, qualitative differences were observed. Genes involved during the defence response to pathogen infection or in programmed cell death were identified, such as pathogenesis related-proteins, trypsin inhibitor or oxalate oxidase, and some of them showed an in silico differential expression between the resistant and the susceptible interactions. Conclusions As far as is known this is the first EST resource from the cacao–M. perniciosa interaction and it is believed that it will provide a significant contribution to the understanding of the molecular mechanisms of the resistance and susceptibility of cacao to M. perniciosa, to develop strategies to control witches broom, and as a source of polymorphism for molecular marker development and marker-assisted selection. PMID:17557832

Construction of BAC Libraries from Flow-Sorted Chromosomes.

PubMed

Šafář, Jan; Šimková, Hana; Doležel, Jaroslav

2016-01-01

Cloned DNA libraries in bacterial artificial chromosome (BAC) are the most widely used form of large-insert DNA libraries. BAC libraries are typically represented by ordered clones derived from genomic DNA of a particular organism. In the case of large eukaryotic genomes, whole-genome libraries consist of a hundred thousand to a million clones, which make their handling and screening a daunting task. The labor and cost of working with whole-genome libraries can be greatly reduced by constructing a library derived from a smaller part of the genome. Here we describe construction of BAC libraries from mitotic chromosomes purified by flow cytometric sorting. Chromosome-specific BAC libraries facilitate positional gene cloning, physical mapping, and sequencing in complex plant genomes.

GenoCAD Plant Grammar to Design Plant Expression Vectors for Promoter Analysis.

PubMed

Coll, Anna; Wilson, Mandy L; Gruden, Kristina; Peccoud, Jean

2016-01-01

With the rapid advances in prediction tools for discovery of new promoters and their cis-elements, there is a need to improve plant expression methodologies in order to facilitate a high-throughput functional validation of these promoters in planta. The promoter-reporter analysis is an indispensible approach for characterization of plant promoters. It requires the design of complex plant expression vectors, which can be challenging. Here, we describe the use of a plant grammar implemented in GenoCAD that will allow the users to quickly design constructs for promoter analysis experiments but also for other in planta functional studies. The GenoCAD plant grammar includes a library of plant biological parts organized in structural categories to facilitate their use and management and a set of rules that guides the process of assembling these biological parts into large constructs.

An Automated Pipeline for Engineering Many-Enzyme Pathways: Computational Sequence Design, Pathway Expression-Flux Mapping, and Scalable Pathway Optimization.

PubMed

Halper, Sean M; Cetnar, Daniel P; Salis, Howard M

2018-01-01

Engineering many-enzyme metabolic pathways suffers from the design curse of dimensionality. There are an astronomical number of synonymous DNA sequence choices, though relatively few will express an evolutionary robust, maximally productive pathway without metabolic bottlenecks. To solve this challenge, we have developed an integrated, automated computational-experimental pipeline that identifies a pathway's optimal DNA sequence without high-throughput screening or many cycles of design-build-test. The first step applies our Operon Calculator algorithm to design a host-specific evolutionary robust bacterial operon sequence with maximally tunable enzyme expression levels. The second step applies our RBS Library Calculator algorithm to systematically vary enzyme expression levels with the smallest-sized library. After characterizing a small number of constructed pathway variants, measurements are supplied to our Pathway Map Calculator algorithm, which then parameterizes a kinetic metabolic model that ultimately predicts the pathway's optimal enzyme expression levels and DNA sequences. Altogether, our algorithms provide the ability to efficiently map the pathway's sequence-expression-activity space and predict DNA sequences with desired metabolic fluxes. Here, we provide a step-by-step guide to applying the Pathway Optimization Pipeline on a desired multi-enzyme pathway in a bacterial host.

Annual Program: Library Services and Construction Act, 1987-1988.

ERIC Educational Resources Information Center

South Carolina State Library, Columbia.

This report presents the 1978-1988 annual Library Services and Construction Act (LSCA) program for the South Carolina State Library. This program includes fiscal information and project descriptions for the following LCSA projects under Title I-Library Services: (1) Projects IA-General Administration; (2) IB-Library Interpretation; (3) IIA-General…

tCRISPRi: tunable and reversible, one-step control of gene expression

NASA Astrophysics Data System (ADS)

Li, Xin-Tian; Jun, Yonggun; Erickstad, Michael J.; Brown, Steven D.; Parks, Adam; Court, Donald L.; Jun, Suckjoon

2016-12-01

The ability to control the level of gene expression is a major quest in biology. A widely used approach employs deletion of a nonessential gene of interest (knockout), or multi-step recombineering to move a gene of interest under a repressible promoter (knockdown). However, these genetic methods are laborious, and limited for quantitative study. Here, we report a tunable CRISPR-cas system, “tCRISPRi”, for precise and continuous titration of gene expression by more than 30-fold. Our tCRISPRi system employs various previous advancements into a single strain: (1) We constructed a new strain containing a tunable arabinose operon promoter PBAD to quantitatively control the expression of CRISPR-(d)Cas protein over two orders of magnitude in a plasmid-free system. (2) tCRISPRi is reversible, and gene expression is repressed under knockdown conditions. (3) tCRISPRi shows significantly less than 10% leaky expression. (4) Most important from a practical perspective, construction of tCRISPRi to target a new gene requires only one-step of oligo recombineering. Our results show that tCRISPRi, in combination with recombineering, provides a simple and easy-to-implement tool for gene expression control, and is ideally suited for construction of both individual strains and high-throughput tunable knockdown libraries.

Screening and identification of human ZnT8-specific single-chain variable fragment (scFv) from type 1 diabetes phage display library.

PubMed

Wu, Qian; Wang, Xiaodong; Gu, Yong; Zhang, Xiao; Qin, Yao; Chen, Heng; Xu, Xinyu; Yang, Tao; Zhang, Mei

2016-07-01

Zinc transporter 8 (ZnT8) is a major autoantigen and a predictive marker in type 1 diabetes (T1D). To investigate ZnT8-specific antibodies, a phage display library from T1D was constructed and single-chain antibodies against ZnT8 were screened and identified. Human T1D single-chain variable fragment (scFv) phage display library consists of approximately 1×10(8) clones. After four rounds of bio-panning, seven unique clones were positive by phage ELISA. Among them, C27 and C22, which demonstrated the highest affinity to ZnT8, were expressed in Escherichia coli Top10F' and then purified by affinity chromatography. C27 and C22 specifically bound ZnT8 N/C fusion protein and ZnT8 C terminal dimer with one Arg325Trp mutation. The specificity to human islet cells of these scFvs were further confirmed by immunohistochemistry. In conclusion, we have successfully constructed a T1D phage display antibody library and identified two ZnT8-specific scFv clones, C27 and C22. These ZnT8-specific scFvs are potential agents in immunodiagnostic and immunotherapy of T1D.

Construction of C35 gene bait recombinants and T47D cell cDNA library.

PubMed

Yin, Kun; Xu, Chao; Zhao, Gui-Hua; Liu, Ye; Xiao, Ting; Zhu, Song; Yan, Ge

2017-11-20

C35 is a novel tumor biomarker associated with metastasis progression. To investigate the interaction factors of C35 in its high expressed breast cancer cell lines, we constructed bait recombinant plasmids of C35 gene and T47D cell cDNA library for yeast two-hybrid screening. Full length C35 sequences were subcloned using RT-PCR from cDNA template extracted from T47D cells. Based on functional domain analysis, the full-length C35 1-348bp was also truncated into two fragments C351-153bp and C35154-348bp to avoid auto-activation. The three kinds of C35 genes were successfully amplified and inserted into pGBKT7 to construct bait recombinant plasmids pGBKT7-C351-348bp, pGBKT7-C351-153bp and pGBKT7-C35154-348bp, then transformed into Y187 yeast cells by the lithium acetate method. Auto-activation and toxicity of C35 baits were detected using nutritional deficient medium and X-α-Gal assays. The T47D cell ds cDNA was generated by SMART TM technology and the library was constructed using in vivo recombination-mediated cloning in the AH109 yeast strain using a pGADT7-Rec plasmid. The transformed Y187/pGBKT7-C351-348bp line was intensively inhibited while the truncated Y187/pGBKT7-C35 lines had no auto-activation and toxicity in yeast cells. The titer of established cDNA library was 2 × 10 7 pfu/mL with high transformation efficiency of 1.4 × 10 6 , and the insert size of ds cDNA was distributed homogeneously between 0.5-2.0 kb. Our research generated a T47D cell cDNA library with high titer, and the constructed two C35 "baits" contained a respective functional immunoreceptor tyrosine based activation motif (ITAM) and the conserved last four amino acids Cys-Ile-Leu-Val (CILV) motif, and therefore laid a foundation for screening the C35 interaction factors in a BC cell line.

Engineering improved bio-jet fuel tolerance in Escherichia coli using a transgenic library from the hydrocarbon-degrader Marinobacter aquaeolei.

PubMed

Tomko, Timothy A; Dunlop, Mary J

2015-01-01

Recent metabolic engineering efforts have generated microorganisms that can produce biofuels, including bio-jet fuels, however these fuels are often toxic to cells, limiting production yields. There are natural examples of microorganisms that have evolved mechanisms for tolerating hydrocarbon-rich environments, such as those that thrive near natural oil seeps and in oil-polluted waters. Using genomic DNA from the hydrocarbon-degrading microbe Marinobacter aquaeolei, we constructed a transgenic library that we expressed in Escherichia coli. We exposed cells to inhibitory levels of pinene, a monoterpene that can serve as a jet fuel precursor with chemical properties similar to existing tactical fuels. Using a sequential strategy with a fosmid library followed by a plasmid library, we were able to isolate a region of DNA from the M. aquaeolei genome that conferred pinene tolerance when expressed in E. coli. We determined that a single gene, yceI, was responsible for the tolerance improvements. Overexpression of this gene placed no additional burden on the host. We also tested tolerance to other monoterpenes and showed that yceI selectively improves tolerance. The genomes of hydrocarbon-tolerant microbes represent a rich resource for tolerance engineering. Using a transgenic library, we were able to identify a single gene that improves E. coli's tolerance to the bio-jet fuel precursor pinene.

Peanut gene expression profiling in developing seeds at different reproduction stages during Aspergillus parasiticus infection

PubMed Central

Guo, Baozhu; Chen, Xiaoping; Dang, Phat; Scully, Brian T; Liang, Xuanqiang; Holbrook, C Corley; Yu, Jiujiang; Culbreath, Albert K

2008-01-01

Background Peanut (Arachis hypogaea L.) is an important crop economically and nutritionally, and is one of the most susceptible host crops to colonization of Aspergillus parasiticus and subsequent aflatoxin contamination. Knowledge from molecular genetic studies could help to devise strategies in alleviating this problem; however, few peanut DNA sequences are available in the public database. In order to understand the molecular basis of host resistance to aflatoxin contamination, a large-scale project was conducted to generate expressed sequence tags (ESTs) from developing seeds to identify resistance-related genes involved in defense response against Aspergillus infection and subsequent aflatoxin contamination. Results We constructed six different cDNA libraries derived from developing peanut seeds at three reproduction stages (R5, R6 and R7) from a resistant and a susceptible cultivated peanut genotypes, 'Tifrunner' (susceptible to Aspergillus infection with higher aflatoxin contamination and resistant to TSWV) and 'GT-C20' (resistant to Aspergillus with reduced aflatoxin contamination and susceptible to TSWV). The developing peanut seed tissues were challenged by A. parasiticus and drought stress in the field. A total of 24,192 randomly selected cDNA clones from six libraries were sequenced. After removing vector sequences and quality trimming, 21,777 high-quality EST sequences were generated. Sequence clustering and assembling resulted in 8,689 unique EST sequences with 1,741 tentative consensus EST sequences (TCs) and 6,948 singleton ESTs. Functional classification was performed according to MIPS functional catalogue criteria. The unique EST sequences were divided into twenty-two categories. A similarity search against the non-redundant protein database available from NCBI indicated that 84.78% of total ESTs showed significant similarity to known proteins, of which 165 genes had been previously reported in peanuts. There were differences in overall expression patterns in different libraries and genotypes. A number of sequences were expressed throughout all of the libraries, representing constitutive expressed sequences. In order to identify resistance-related genes with significantly differential expression, a statistical analysis to estimate the relative abundance (R) was used to compare the relative abundance of each gene transcripts in each cDNA library. Thirty six and forty seven unique EST sequences with threshold of R > 4 from libraries of 'GT-C20' and 'Tifrunner', respectively, were selected for examination of temporal gene expression patterns according to EST frequencies. Nine and eight resistance-related genes with significant up-regulation were obtained in 'GT-C20' and 'Tifrunner' libraries, respectively. Among them, three genes were common in both genotypes. Furthermore, a comparison of our EST sequences with other plant sequences in the TIGR Gene Indices libraries showed that the percentage of peanut EST matched to Arabidopsis thaliana, maize (Zea mays), Medicago truncatula, rapeseed (Brassica napus), rice (Oryza sativa), soybean (Glycine max) and wheat (Triticum aestivum) ESTs ranged from 33.84% to 79.46% with the sequence identity ≥ 80%. These results revealed that peanut ESTs are more closely related to legume species than to cereal crops, and more homologous to dicot than to monocot plant species. Conclusion The developed ESTs can be used to discover novel sequences or genes, to identify resistance-related genes and to detect the differences among alleles or markers between these resistant and susceptible peanut genotypes. Additionally, this large collection of cultivated peanut EST sequences will make it possible to construct microarrays for gene expression studies and for further characterization of host resistance mechanisms. It will be a valuable genomic resource for the peanut community. The 21,777 ESTs have been deposited to the NCBI GenBank database with accession numbers ES702769 to ES724546. PMID:18248674

The Carnegie Protein Trap Library: A Versatile Tool for Drosophila Developmental Studies

PubMed Central

Buszczak, Michael; Paterno, Shelley; Lighthouse, Daniel; Bachman, Julia; Planck, Jamie; Owen, Stephenie; Skora, Andrew D.; Nystul, Todd G.; Ohlstein, Benjamin; Allen, Anna; Wilhelm, James E.; Murphy, Terence D.; Levis, Robert W.; Matunis, Erika; Srivali, Nahathai; Hoskins, Roger A.; Spradling, Allan C.

2007-01-01

Metazoan physiology depends on intricate patterns of gene expression that remain poorly known. Using transposon mutagenesis in Drosophila, we constructed a library of 7404 protein trap and enhancer trap lines, the Carnegie collection, to facilitate gene expression mapping at single-cell resolution. By sequencing the genomic insertion sites, determining splicing patterns downstream of the enhanced green fluorescent protein (EGFP) exon, and analyzing expression patterns in the ovary and salivary gland, we found that 600–900 different genes are trapped in our collection. A core set of 244 lines trapped different identifiable protein isoforms, while insertions likely to act as GFP-enhancer traps were found in 256 additional genes. At least 8 novel genes were also identified. Our results demonstrate that the Carnegie collection will be useful as a discovery tool in diverse areas of cell and developmental biology and suggest new strategies for greatly increasing the coverage of the Drosophila proteome with protein trap insertions. PMID:17194782

Identification of differentially expressed genes in human lung squamous cell carcinoma using suppression subtractive hybridization.

PubMed

Sun, Wenyue; Zhang, Kaitai; Zhang, Xinyu; Lei, Wendong; Xiao, Ting; Ma, Jinfang; Guo, Suping; Shao, Shujuan; Zhang, Husheng; Liu, Yan; Yuan, Jinsong; Hu, Zhi; Ma, Ying; Feng, Xiaoli; Hu, Songnian; Zhou, Jun; Cheng, Shujun; Gao, Yanning

2004-08-20

Lung cancer is one of the major causes of cancer-related deaths. Over the past decade, much has been known about the molecular changes associated with lung carcinogenesis; however, our understanding to lung tumorigenesis is still incomplete. To identify genes that are differentially expressed in squamous cell carcinoma (SCC) of the lung, we compared the expression profiles between primarily cultured SCC tumor cells and bronchial epithelial cells derived from morphologically normal bronchial epithelium of the same patient. Using suppression subtractive hybridization (SSH), two cDNA libraries containing up- and down-regulated genes in the tumor cells were constructed, named as LCTP and LCBP. The two libraries comprise 258 known genes and 133 unknown genes in total. The known up-regulated genes in the library LCTP represented a variety of functional groups; including metabolism-, cell adhesion and migration-, signal transduction-, and anti-apoptosis-related genes. Using semi-quantitative reverse transcription-polymerase chain reaction, seven genes chosen randomly from the LCTP were analyzed in the tumor tissue paired with its corresponding adjacent normal lung tissue derived from 16 cases of the SCC. Among them, the IQGAP1, RAP1GDS1, PAICS, MLF1, and MARK1 genes showed a consistent expression pattern with that of the SSH analysis. Identification and further characterization of these genes may allow a better understanding of lung carcinogenesis.

Gene expression profile of human Down syndrome leukocytes.

PubMed

Malagó, Wilson; Sommer, César A; Del Cistia Andrade, Camillo; Soares-Costa, Andrea; Abrao Possik, Patricia; Cassago, Alexandre; Santejo Silveira, Henrique C; Henrique-Silva, Flavio

2005-08-01

Identification of differences in the gene expression patterns of Down syndrome and normal leukocytes. We constructed the first Down syndrome leukocyte serial analysis of gene expression (SAGE) library from a 28 year-old patient. This library was analyzed and compared with a normal leukocyte SAGE library using the eSAGE software. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to validate the results. We found that a large number of unidentified transcripts were overexpressed in Down syndrome leukocytes and some transcripts coding for growth factors (e.g. interleukin 8, IL-8), ribosomaproteins (e.g. L13a, L29, and L37), and transcription factors (e.g., Jun B, Jun D, and C/EBP beta) were underexpressed. The SAGE data were successfully validated for the genes IL-8, CXCR4, BCL2A1, L13a, L29, L37, and GTF3A using RT-PCR. Our analysis identified significant changes in the expression pattern of Down syndrome leukocytes compared with normal ones, including key regulators of growth and proliferation, ribosomal proteins, and a large number of overexpressed transcripts that were not matched in UniGene clusters and that may represent novel genes related to Down syndrome. This study offers a new insight into transcriptional changes in Down syndrome leukocytes and indicates candidate genes for further investigations into the molecular mechanism of Down syndrome pathology.

Design and construction of a first-generation high-throughput integrated robotic molecular biology platform for bioenergy applications.

PubMed

Hughes, Stephen R; Butt, Tauseef R; Bartolett, Scott; Riedmuller, Steven B; Farrelly, Philip

2011-08-01

The molecular biological techniques for plasmid-based assembly and cloning of gene open reading frames are essential for elucidating the function of the proteins encoded by the genes. High-throughput integrated robotic molecular biology platforms that have the capacity to rapidly clone and express heterologous gene open reading frames in bacteria and yeast and to screen large numbers of expressed proteins for optimized function are an important technology for improving microbial strains for biofuel production. The process involves the production of full-length complementary DNA libraries as a source of plasmid-based clones to express the desired proteins in active form for determination of their functions. Proteins that were identified by high-throughput screening as having desired characteristics are overexpressed in microbes to enable them to perform functions that will allow more cost-effective and sustainable production of biofuels. Because the plasmid libraries are composed of several thousand unique genes, automation of the process is essential. This review describes the design and implementation of an automated integrated programmable robotic workcell capable of producing complementary DNA libraries, colony picking, isolating plasmid DNA, transforming yeast and bacteria, expressing protein, and performing appropriate functional assays. These operations will allow tailoring microbial strains to use renewable feedstocks for production of biofuels, bioderived chemicals, fertilizers, and other coproducts for profitable and sustainable biorefineries. Published by Elsevier Inc.

Annual Program. Library Services and Construction Act, 1988-1989.

ERIC Educational Resources Information Center

South Carolina State Library, Columbia.

This report presents the 1988-1989 annual Library Services and Construction Act (LSCA) program for the South Carolina State Library. This program includes fiscal information and project descriptions for the following LSCA projects under Title I Library Services: (1) I-A, General Administration; (2) I-B, Library Interpretation; (3) II-A, General…

Assignment of chromosomal locus and evidence for alternatively spliced mRNAs of a human sperm membrane protein (hSMP-1).

PubMed

Wang, H; Miao, S; Chen, D; Wang, L; Koide, S S

1999-10-06

The gene (HSD-1) coding a human sperm membrane protein (hSMP-1) was isolated from a human testis cDNA expression library using antibodies found in the serum of an infertile woman. HSD-1 was localized to a single locus on chromosome 9 and assigned to band 9p12-p13 by fluorescent in situ hybridization (FISH) mapping and DAPI (4,6-diamidino-2-phenylindole) banding, using rat/human somatic cell hybrids and metaphase chromosomes of human lymphocytes. In rescreening a testis lambdagt10 cDNA expression library, the full-length cDNA (HSD-1) and several truncated cDNAs with heterologous regions were isolated from positive clones. The heterology consisted of deletion, insertion and alteration of the 5'-end. These heterologous truncated fragments may be produced by alternative splicing of mRNAs. Two recombinant prokaryotic expression vectors were constructed with one of the heterologous fragment (clone #26) with and without the alternative 5'-end. Escherichia coli transfected with the construct containing the alternative 5'-end failed to produce the recombinant product, whereas those transfected with the vector lacking the 5'-end produced hSMP-1. DNASIS analysis of the structure of #26 mRNA suggests that the 5'-end has a stable secondary configuration that may maintain the mRNA in an inactivated state, whereby hindering its translation and preventing the expression of the gene.

Characterization of skin ulceration syndrome associated microRNAs in sea cucumber Apostichopus japonicus by deep sequencing.

PubMed

Li, Chenghua; Feng, Weida; Qiu, Lihua; Xia, Changge; Su, Xiurong; Jin, Chunhua; Zhou, Tingting; Zeng, Yuan; Li, Taiwu

2012-08-01

MicroRNAs (miRNAs) constitute a family of small RNA species which have been demonstrated to be one of key effectors in mediating host-pathogen interaction. In this study, two haemocytes miRNA libraries were constructed with deep sequenced by illumina Hiseq2000 from healthy (L1) and skin ulceration syndrome Apostichopus japonicus (L2). The high throughput solexa sequencing resulted in 9,579,038 and 7,742,558 clean data from L1 and L2, respectively. Sequences analysis revealed that 40 conserved miRNAs were found in both libraries, in which let-7 and mir-125 were speculated to be clustered together and expressed accordingly. Eighty-six miRNA candidates were also identified by reference genome search and stem-loop structure prediction. Importantly, mir-31 and mir-2008 displayed significant differential expression between the two libraries according to FPKM model, which might be considered as promising targets for elucidating the intrinsic mechanism of skin ulceration syndrome outbreak in the species. Copyright © 2012 Elsevier Ltd. All rights reserved.

From Genes to Protein Mechanics on a Chip

PubMed Central

Milles, Lukas F.; Verdorfer, Tobias; Pippig, Diana A.; Nash, Michael A.; Gaub, Hermann E.

2014-01-01

Single-molecule force spectroscopy enables mechanical testing of individual proteins, however low experimental throughput limits the ability to screen constructs in parallel. We describe a microfluidic platform for on-chip protein expression and measurement of single-molecule mechanical properties. We constructed microarrays of proteins covalently attached to a chip surface, and found that a single cohesin-modified cantilever that bound to the terminal dockerin-tag of each protein remained stable over thousands of pulling cycles. The ability to synthesize and mechanically probe protein libraries presents new opportunities for high-throughput mechanical phenotyping. PMID:25194847

Analysis of expressed sequence tags from Prunus mume flower and fruit and development of simple sequence repeat markers

PubMed Central

2010-01-01

Background Expressed Sequence Tag (EST) has been a cost-effective tool in molecular biology and represents an abundant valuable resource for genome annotation, gene expression, and comparative genomics in plants. Results In this study, we constructed a cDNA library of Prunus mume flower and fruit, sequenced 10,123 clones of the library, and obtained 8,656 expressed sequence tag (EST) sequences with high quality. The ESTs were assembled into 4,473 unigenes composed of 1,492 contigs and 2,981 singletons and that have been deposited in NCBI (accession IDs: GW868575 - GW873047), among which 1,294 unique ESTs were with known or putative functions. Furthermore, we found 1,233 putative simple sequence repeats (SSRs) in the P. mume unigene dataset. We randomly tested 42 pairs of PCR primers flanking potential SSRs, and 14 pairs were identified as true-to-type SSR loci and could amplify polymorphic bands from 20 individual plants of P. mume. We further used the 14 EST-SSR primer pairs to test the transferability on peach and plum. The result showed that nearly 89% of the primer pairs produced target PCR bands in the two species. A high level of marker polymorphism was observed in the plum species (65%) and low in the peach (46%), and the clustering analysis of the three species indicated that these SSR markers were useful in the evaluation of genetic relationships and diversity between and within the Prunus species. Conclusions We have constructed the first cDNA library of P. mume flower and fruit, and our data provide sets of molecular biology resources for P. mume and other Prunus species. These resources will be useful for further study such as genome annotation, new gene discovery, gene functional analysis, molecular breeding, evolution and comparative genomics between Prunus species. PMID:20626882

T7 lytic phage-displayed peptide libraries: construction and diversity characterization.

PubMed

Krumpe, Lauren R H; Mori, Toshiyuki

2014-01-01

In this chapter, we describe the construction of T7 bacteriophage (phage)-displayed peptide libraries and the diversity analyses of random amino acid sequences obtained from the libraries. We used commercially available reagents, Novagen's T7Select system, to construct the libraries. Using a combination of biotinylated extension primer and streptavidin-coupled magnetic beads, we were able to prepare library DNA without applying gel purification, resulting in extremely high ligation efficiencies. Further, we describe the use of bioinformatics tools to characterize library diversity. Amino acid frequency and positional amino acid diversity and hydropathy are estimated using the REceptor LIgand Contacts website http://relic.bio.anl.gov. Peptide net charge analysis and peptide hydropathy analysis are conducted using the Genetics Computer Group Wisconsin Package computational tools. A comprehensive collection of the estimated number of recombinants and titers of T7 phage-displayed peptide libraries constructed in our lab is included.

Preparing and Analyzing Expressed Sequence Tags (ESTs) Library for the Mammary Tissue of Local Turkish Kivircik Sheep

PubMed Central

Omeroglu Ulu, Zehra; Ulu, Salih; Un, Cemal; Ozdem Oztabak, Kemal; Altunatmaz, Kemal

2017-01-01

Kivircik sheep is an important local Turkish sheep according to its meat quality and milk productivity. The aim of this study was to analyze gene expression profiles of both prenatal and postnatal stages for the Kivircik sheep. Therefore, two different cDNA libraries, which were taken from the same Kivircik sheep mammary gland tissue at prenatal and postnatal stages, were constructed. Total 3072 colonies which were randomly selected from the two libraries were sequenced for developing a sheep ESTs collection. We used Phred/Phrap computer programs for analysis of the raw EST and readable EST sequences were assembled with the CAP3 software. Putative functions of all unique sequences and statistical analysis were determined by Geneious software. Total 422 ESTs have over 80% similarity to known sequences of other organisms in NCBI classified by Panther database for the Gene Ontology (GO) category. By comparing gene expression profiles, we observed some putative genes that may be relative to reproductive performance or play important roles in milk synthesis and secretion. A total of 2414 ESTs have been deposited to the NCBI GenBank database (GW996847–GW999260). EST data in this study have provided a new source of information to functional genome studies of sheep. PMID:28239610

Flow cytometric purification of Colletotrichum higginsianum biotrophic hyphae from Arabidopsis leaves for stage-specific transcriptome analysis.

PubMed

Takahara, Hiroyuki; Dolf, Andreas; Endl, Elmar; O'Connell, Richard

2009-08-01

Generation of stage-specific cDNA libraries is a powerful approach to identify pathogen genes that are differentially expressed during plant infection. Biotrophic pathogens develop specialized infection structures inside living plant cells, but sampling the transcriptome of these structures is problematic due to the low ratio of fungal to plant RNA, and the lack of efficient methods to isolate them from infected plants. Here we established a method, based on fluorescence-activated cell sorting (FACS), to purify the intracellular biotrophic hyphae of Colletotrichum higginsianum from homogenates of infected Arabidopsis leaves. Specific selection of viable hyphae using a fluorescent vital marker provided intact RNA for cDNA library construction. Pilot-scale sequencing showed that the library was enriched with plant-induced and pathogenicity-related fungal genes, including some encoding small, soluble secreted proteins that represent candidate fungal effectors. The high purity of the hyphae (94%) prevented contamination of the library by sequences derived from host cells or other fungal cell types. RT-PCR confirmed that genes identified in the FACS-purified hyphae were also expressed in planta. The method has wide applicability for isolating the infection structures of other plant pathogens, and will facilitate cell-specific transcriptome analysis via deep sequencing and microarray hybridization, as well as proteomic analyses.

Generation and analysis of expressed sequence tags from a cDNA library of the fruiting body of Ganoderma lucidum

PubMed Central

2010-01-01

Background Little genomic or trancriptomic information on Ganoderma lucidum (Lingzhi) is known. This study aims to discover the transcripts involved in secondary metabolite biosynthesis and developmental regulation of G. lucidum using an expressed sequence tag (EST) library. Methods A cDNA library was constructed from the G. lucidum fruiting body. Its high-quality ESTs were assembled into unique sequences with contigs and singletons. The unique sequences were annotated according to sequence similarities to genes or proteins available in public databases. The detection of simple sequence repeats (SSRs) was preformed by online analysis. Results A total of 1,023 clones were randomly selected from the G. lucidum library and sequenced, yielding 879 high-quality ESTs. These ESTs showed similarities to a diverse range of genes. The sequences encoding squalene epoxidase (SE) and farnesyl-diphosphate synthase (FPS) were identified in this EST collection. Several candidate genes, such as hydrophobin, MOB2, profilin and PHO84 were detected for the first time in G. lucidum. Thirteen (13) potential SSR-motif microsatellite loci were also identified. Conclusion The present study demonstrates a successful application of EST analysis in the discovery of transcripts involved in the secondary metabolite biosynthesis and the developmental regulation of G. lucidum. PMID:20230644

Transcriptome analysis of Schistosoma mansoni larval development using serial analysis of gene expression (SAGE).

PubMed

Taft, A S; Vermeire, J J; Bernier, J; Birkeland, S R; Cipriano, M J; Papa, A R; McArthur, A G; Yoshino, T P

2009-04-01

Infection of the snail, Biomphalaria glabrata, by the free-swimming miracidial stage of the human blood fluke, Schistosoma mansoni, and its subsequent development to the parasitic sporocyst stage is critical to establishment of viable infections and continued human transmission. We performed a genome-wide expression analysis of the S. mansoni miracidia and developing sporocyst using Long Serial Analysis of Gene Expression (LongSAGE). Five cDNA libraries were constructed from miracidia and in vitro cultured 6- and 20-day-old sporocysts maintained in sporocyst medium (SM) or in SM conditioned by previous cultivation with cells of the B. glabrata embryonic (Bge) cell line. We generated 21 440 SAGE tags and mapped 13 381 to the S. mansoni gene predictions (v4.0e) either by estimating theoretical 3' UTR lengths or using existing 3' EST sequence data. Overall, 432 transcripts were found to be differentially expressed amongst all 5 libraries. In total, 172 tags were differentially expressed between miracidia and 6-day conditioned sporocysts and 152 were differentially expressed between miracidia and 6-day unconditioned sporocysts. In addition, 53 and 45 tags, respectively, were differentially expressed in 6-day and 20-day cultured sporocysts, due to the effects of exposure to Bge cell-conditioned medium.

A synthetic promoter library for constitutive gene expression in Lactobacillus plantarum.

PubMed

Rud, Ida; Jensen, Peter Ruhdal; Naterstad, Kristine; Axelsson, Lars

2006-04-01

A synthetic promoter library (SPL) for Lactobacillus plantarum has been developed, which generalizes the approach for obtaining synthetic promoters. The consensus sequence, derived from rRNA promoters extracted from the L. plantarum WCFS1 genome, was kept constant, and the non-consensus sequences were randomized. Construction of the SPL was performed in a vector (pSIP409) previously developed for high-level, inducible gene expression in L. plantarum and Lactobacillus sakei. A wide range of promoter strengths was obtained with the approach, covering 3-4 logs of expression levels in small increments of activity. The SPL was evaluated for the ability to drive beta-glucuronidase (GusA) and aminopeptidase N (PepN) expression. Protein production from the synthetic promoters was constitutive, and the most potent promoters gave high protein production with levels comparable to those of native rRNA promoters, and production of PepN protein corresponding to approximately 10-15 % of the total cellular protein. High correlation was obtained between the activities of promoters when tested in L. sakei and L. plantarum, which indicates the potential of the SPL for other Lactobacillus species. The SPL enables fine-tuning of stable gene expression for various applications in L. plantarum.

Deep learning of the regulatory grammar of yeast 5′ untranslated regions from 500,000 random sequences

PubMed Central

Groves, Benjamin; Kuchina, Anna; Rosenberg, Alexander B.; Jojic, Nebojsa; Fields, Stanley; Seelig, Georg

2017-01-01

Our ability to predict protein expression from DNA sequence alone remains poor, reflecting our limited understanding of cis-regulatory grammar and hampering the design of engineered genes for synthetic biology applications. Here, we generate a model that predicts the protein expression of the 5′ untranslated region (UTR) of mRNAs in the yeast Saccharomyces cerevisiae. We constructed a library of half a million 50-nucleotide-long random 5′ UTRs and assayed their activity in a massively parallel growth selection experiment. The resulting data allow us to quantify the impact on protein expression of Kozak sequence composition, upstream open reading frames (uORFs), and secondary structure. We trained a convolutional neural network (CNN) on the random library and showed that it performs well at predicting the protein expression of both a held-out set of the random 5′ UTRs as well as native S. cerevisiae 5′ UTRs. The model additionally was used to computationally evolve highly active 5′ UTRs. We confirmed experimentally that the great majority of the evolved sequences led to higher protein expression rates than the starting sequences, demonstrating the predictive power of this model. PMID:29097404

Genomic resources for Myzus persicae: EST sequencing, SNP identification, and microarray design

PubMed Central

Ramsey, John S; Wilson, Alex CC; de Vos, Martin; Sun, Qi; Tamborindeguy, Cecilia; Winfield, Agnese; Malloch, Gaynor; Smith, Dawn M; Fenton, Brian; Gray, Stewart M; Jander, Georg

2007-01-01

Background The green peach aphid, Myzus persicae (Sulzer), is a world-wide insect pest capable of infesting more than 40 plant families, including many crop species. However, despite the significant damage inflicted by M. persicae in agricultural systems through direct feeding damage and by its ability to transmit plant viruses, limited genomic information is available for this species. Results Sequencing of 16 M. persicae cDNA libraries generated 26,669 expressed sequence tags (ESTs). Aphids for library construction were raised on Arabidopsis thaliana, Nicotiana benthamiana, Brassica oleracea, B. napus, and Physalis floridana (with and without Potato leafroll virus infection). The M. persicae cDNA libraries include ones made from sexual and asexual whole aphids, guts, heads, and salivary glands. In silico comparison of cDNA libraries identified aphid genes with tissue-specific expression patterns, and gene expression that is induced by feeding on Nicotiana benthamiana. Furthermore, 2423 genes that are novel to science and potentially aphid-specific were identified. Comparison of cDNA data from three aphid lineages identified single nucleotide polymorphisms that can be used as genetic markers and, in some cases, may represent functional differences in the protein products. In particular, non-conservative amino acid substitutions in a highly expressed gut protease may be of adaptive significance for M. persicae feeding on different host plants. The Agilent eArray platform was used to design an M. persicae oligonucleotide microarray representing over 10,000 unique genes. Conclusion New genomic resources have been developed for M. persicae, an agriculturally important insect pest. These include previously unknown sequence data, a collection of expressed genes, molecular markers, and a DNA microarray that can be used to study aphid gene expression. These resources will help elucidate the adaptations that allow M. persicae to develop compatible interactions with its host plants, complementing ongoing work illuminating plant molecular responses to phloem-feeding insects. PMID:18021414

Spectrum-based method to generate good decoy libraries for spectral library searching in peptide identifications.

PubMed

Cheng, Chia-Ying; Tsai, Chia-Feng; Chen, Yu-Ju; Sung, Ting-Yi; Hsu, Wen-Lian

2013-05-03

As spectral library searching has received increasing attention for peptide identification, constructing good decoy spectra from the target spectra is the key to correctly estimating the false discovery rate in searching against the concatenated target-decoy spectral library. Several methods have been proposed to construct decoy spectral libraries. Most of them construct decoy peptide sequences and then generate theoretical spectra accordingly. In this paper, we propose a method, called precursor-swap, which directly constructs decoy spectral libraries directly at the "spectrum level" without generating decoy peptide sequences by swapping the precursors of two spectra selected according to a very simple rule. Our spectrum-based method does not require additional efforts to deal with ion types (e.g., a, b or c ions), fragment mechanism (e.g., CID, or ETD), or unannotated peaks, but preserves many spectral properties. The precursor-swap method is evaluated on different spectral libraries and the results of obtained decoy ratios show that it is comparable to other methods. Notably, it is efficient in time and memory usage for constructing decoy libraries. A software tool called Precursor-Swap-Decoy-Generation (PSDG) is publicly available for download at http://ms.iis.sinica.edu.tw/PSDG/.

NOAA Photo Library - Credits

Science.gov Websites

NOAA Photo Library Banner Takes you to the Top Page Takes you to the About this Site page. Takes . Skip Theberge (NOAA Central Library) -- Collection development, site content, image digitization, and database construction. Kristin Ward (NOAA Central Library) -- HTML page construction Without the generosity

Scaling up the 454 Titanium Library Construction and Pooling of Barcoded Libraries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phung, Wilson; Hack, Christopher; Shapiro, Harris

2009-03-23

We have been developing a high throughput 454 library construction process at the Joint Genome Institute to meet the needs of de novo sequencing a large number of microbial and eukaryote genomes, EST, and metagenome projects. We have been focusing efforts in three areas: (1) modifying the current process to allow the construction of 454 standard libraries on a 96-well format; (2) developing a robotic platform to perform the 454 library construction; and (3) designing molecular barcodes to allow pooling and sorting of many different samples. In the development of a high throughput process to scale up the number ofmore » libraries by adapting the process to a 96-well plate format, the key process change involves the replacement of gel electrophoresis for size selection with Solid Phase Reversible Immobilization (SPRI) beads. Although the standard deviation of the insert sizes increases, the overall quality sequence and distribution of the reads in the genome has not changed. The manual process of constructing 454 shotgun libraries on 96-well plates is a time-consuming, labor-intensive, and ergonomically hazardous process; we have been experimenting to program a BioMek robot to perform the library construction. This will not only enable library construction to be completed in a single day, but will also minimize any ergonomic risk. In addition, we have implemented a set of molecular barcodes (AKA Multiple Identifiers or MID) and a pooling process that allows us to sequence many targets simultaneously. Here we will present the testing of pooling a set of selected fosmids derived from the endomycorrhizal fungus Glomus intraradices. By combining the robotic library construction process and the use of molecular barcodes, it is now possible to sequence hundreds of fosmids that represent a minimal tiling path of this genome. Here we present the progress and the challenges of developing these scaled-up processes.« less

Isolation and expression analysis of cDNAs that are associated with alternate bearing in Olea europaea L. cv. Ayvalık

PubMed Central

2013-01-01

Background Olive cDNA libraries to isolate candidate genes that can help enlightening the molecular mechanism of periodicity and / or fruit production were constructed and analyzed. For this purpose, cDNA libraries from the leaves of trees in “on year” and in “off year” in July (when fruits start to appear) and in November (harvest time) were constructed. Randomly selected 100 positive clones from each library were analyzed with respect to sequence and size. A fruit-flesh cDNA library was also constructed and characterized to confirm the reliability of each library’s temporal and spatial properties. Results Quantitative real-time RT-PCR (qRT-PCR) analyses of the cDNA libraries confirmed cDNA molecules that are associated with different developmental stages (e. g. “on year” leaves in July, “off year” leaves in July, leaves in November) and fruits. Hence, a number of candidate cDNAs associated with “on year” and “off year” were isolated. Comparison of the detected cDNAs to the current EST database of GenBank along with other non - redundant databases of NCBI revealed homologs of previously described genes along with several unknown cDNAs. Of around 500 screened cDNAs, 48 cDNA elements were obtained after eliminating ribosomal RNA sequences. These independent transcripts were analyzed using BLAST searches (cutoff E-value of 1.0E-5) against the KEGG and GenBank nucleotide databases and 37 putative transcripts corresponding to known gene functions were annotated with gene names and Gene Ontology (GO) terms. Transcripts in the biological process were found to be related with metabolic process (27%), cellular process (23%), response to stimulus (17%), localization process (8.5%), multicellular organismal process (6.25%), developmental process (6.25%) and reproduction (4.2%). Conclusions A putative P450 monooxigenase expressed fivefold more in the “on year” than that of “off year” leaves in July. Two putative dehydrins expressed significantly more in “on year” leaves than that of “off year” leaves in November. Homologs of UDP – glucose epimerase, acyl - CoA binding protein, triose phosphate isomerase and a putative nuclear core anchor protein were significant in fruits only, while a homolog of an embryo binding protein / small GTPase regulator was detected in “on year” leaves only. One of the two unknown cDNAs was specific to leaves in July while the other was detected in all of the libraries except fruits. KEGG pathway analyses for the obtained sequences correlated with essential metabolisms such as galactose metabolism, amino sugar and nucleotide sugar metabolisms and photosynthesis. Detailed analysis of the results presents candidate cDNAs that can be used to dissect further the genetic basis of fruit production and / or alternate bearing which causes significant economical loss for olive growers. PMID:23552171

Engineering emergent multicellular behavior through synthetic adhesion

NASA Astrophysics Data System (ADS)

Glass, David; Riedel-Kruse, Ingmar

In over a decade, synthetic biology has developed increasingly robust gene networks within single cells, but constructed very few systems that demonstrate multicellular spatio-temporal dynamics. We are filling this gap in synthetic biology's toolbox by developing an E. coli self-assembly platform based on modular cell-cell adhesion. We developed a system in which adhesive selectivity is provided by a library of outer membrane-displayed peptides with intra-library specificities, while affinity is provided by consistent expression across the entire library. We further provide a biophysical model to help understand the parameter regimes in which this tool can be used to self-assemble into cellular clusters, filaments, or meshes. The combined platform will enable future development of synthetic multicellular systems for use in consortia-based metabolic engineering, in living materials, and in controlled study of minimal multicellular systems. Stanford Bio-X Bowes Fellowship.

Deep sequencing of small RNA libraries reveals dynamic expression patterns of microRNAs in multiple developmental stages of Bactrocera dorsalis.

PubMed

Huang, Y; Dou, W; Liu, B; Wei, D; Liao, C Y; Smagghe, G; Wang, J-J

2014-10-01

In eukaryotes, microRNAs (miRNAs) are small, conserved, noncoding RNAs that have emerged as critical regulators of gene expression. The oriental fruit fly Bactrocera dorsalis is one of the most economically important fruit fly pests in East Asia and the Pacific. Although transcriptome analyses have greatly enriched our knowledge of its structural genes, little is known about post-transcriptional regulation by miRNAs in this dipteran species. In this study, small RNA libraries corresponding to four B. dorsalis developmental stages (eggs, larvae, pupae and adults) were constructed and sequenced. Approximately 30.7 million reads of 18-30 nucleotides were obtained, with 123 known miRNAs and 60 novel miRNAs identified amongst these libraries. More than half of the miRNAs were stage-specific during the four developmental stages. A set of miRNAs was found to be up- or down-regulated during development by comparison of their reads at different developmental stages. Moreover, a small part of miRNAs owned both miR-#-3p and miR-#-5p types, with enormously variable miR-#-3p/miR-#-5p ratios in the same library and amongst different developmental stages for each miRNA. Taking these findings together, the current study has uncovered a number of miRNAs and provided insights into their possible involvement in developmental regulation by expression profiling of miRNAs. Further analyses of the expression and function of these miRNAs could increase our understanding of regulatory networks in this insect and lead to novel approaches for its control. © 2014 The Royal Entomological Society.

Semirational Approach for Ultrahigh Poly(3-hydroxybutyrate) Accumulation in Escherichia coli by Combining One-Step Library Construction and High-Throughput Screening.

PubMed

Li, Teng; Ye, Jianwen; Shen, Rui; Zong, Yeqing; Zhao, Xuejin; Lou, Chunbo; Chen, Guo-Qiang

2016-11-18

As a product of a multistep enzymatic reaction, accumulation of poly(3-hydroxybutyrate) (PHB) in Escherichia coli (E. coli) can be achieved by overexpression of the PHB synthesis pathway from a native producer involving three genes phbC, phbA, and phbB. Pathway optimization by adjusting expression levels of the three genes can influence properties of the final product. Here, we reported a semirational approach for highly efficient PHB pathway optimization in E. coli based on a phbCAB operon cloned from the native producer Ralstonia entropha (R. entropha). Rationally designed ribosomal binding site (RBS) libraries with defined strengths for each of the three genes were constructed based on high or low copy number plasmids in a one-pot reaction by an oligo-linker mediated assembly (OLMA) method. Strains with desired properties were evaluated and selected by three different methodologies, including visual selection, high-throughput screening, and detailed in-depth analysis. Applying this approach, strains accumulating 0%-92% PHB contents in cell dry weight (CDW) were achieved. PHB with various weight-average molecular weights (M w ) of 2.7-6.8 × 10 6 were also efficiently produced in relatively high contents. These results suggest that the semirational approach combining library design, construction, and proper screening is an efficient way to optimize PHB and other multienzyme pathways.

Improving microbial fitness in the mammalian gut by in vivo temporal functional metagenomics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yaung, Stephanie J.; Deng, Luxue; Li, Ning

Elucidating functions of commensal microbial genes in the mammalian gut is challenging because many commensals are recalcitrant to laboratory cultivation and genetic manipulation. We present Temporal FUnctional Metagenomics sequencing (TFUMseq), a platform to functionally mine bacterial genomes for genes that contribute to fitness of commensal bacteria in vivo. Our approach uses metagenomic DNA to construct large-scale heterologous expression libraries that are tracked over time in vivo by deep sequencing and computational methods. To demonstrate our approach, we built a TFUMseq plasmid library using the gut commensal Bacteroides thetaiotaomicron (Bt) and introduced Escherichia coli carrying this library into germfree mice. Populationmore » dynamics of library clones revealed Bt genes conferring significant fitness advantages in E. coli over time, including carbohydrate utilization genes, with a Bt galactokinase central to early colonization, and subsequent dominance by a Bt glycoside hydrolase enabling sucrose metabolism coupled with co-evolution of the plasmid library and E. coli genome driving increased galactose utilization. Here, our findings highlight the utility of functional metagenomics for engineering commensal bacteria with improved properties, including expanded colonization capabilities in vivo.« less

Improving microbial fitness in the mammalian gut by in vivo temporal functional metagenomics

DOE PAGES

Yaung, Stephanie J.; Deng, Luxue; Li, Ning; ...

2015-03-11

Elucidating functions of commensal microbial genes in the mammalian gut is challenging because many commensals are recalcitrant to laboratory cultivation and genetic manipulation. We present Temporal FUnctional Metagenomics sequencing (TFUMseq), a platform to functionally mine bacterial genomes for genes that contribute to fitness of commensal bacteria in vivo. Our approach uses metagenomic DNA to construct large-scale heterologous expression libraries that are tracked over time in vivo by deep sequencing and computational methods. To demonstrate our approach, we built a TFUMseq plasmid library using the gut commensal Bacteroides thetaiotaomicron (Bt) and introduced Escherichia coli carrying this library into germfree mice. Populationmore » dynamics of library clones revealed Bt genes conferring significant fitness advantages in E. coli over time, including carbohydrate utilization genes, with a Bt galactokinase central to early colonization, and subsequent dominance by a Bt glycoside hydrolase enabling sucrose metabolism coupled with co-evolution of the plasmid library and E. coli genome driving increased galactose utilization. Here, our findings highlight the utility of functional metagenomics for engineering commensal bacteria with improved properties, including expanded colonization capabilities in vivo.« less

Biochemical and genetic analysis of the yeast proteome with a movable ORF collection

PubMed Central

Gelperin, Daniel M.; White, Michael A.; Wilkinson, Martha L.; Kon, Yoshiko; Kung, Li A.; Wise, Kevin J.; Lopez-Hoyo, Nelson; Jiang, Lixia; Piccirillo, Stacy; Yu, Haiyuan; Gerstein, Mark; Dumont, Mark E.; Phizicky, Eric M.; Snyder, Michael; Grayhack, Elizabeth J.

2005-01-01

Functional analysis of the proteome is an essential part of genomic research. To facilitate different proteomic approaches, a MORF (moveable ORF) library of 5854 yeast expression plasmids was constructed, each expressing a sequence-verified ORF as a C-terminal ORF fusion protein, under regulated control. Analysis of 5573 MORFs demonstrates that nearly all verified ORFs are expressed, suggests the authenticity of 48 ORFs characterized as dubious, and implicates specific processes including cytoskeletal organization and transcriptional control in growth inhibition caused by overexpression. Global analysis of glycosylated proteins identifies 109 new confirmed N-linked and 345 candidate glycoproteins, nearly doubling the known yeast glycome. PMID:16322557

Construction of a virtual combinatorial library using SMILES strings to discover potential structure-diverse PPAR modulators.

PubMed

Liao, Chenzhong; Liu, Bing; Shi, Leming; Zhou, Jiaju; Lu, Xian-Ping

2005-07-01

Based on the structural characters of PPAR modulators, a virtual combinatorial library containing 1226,625 compounds was constructed using SMILES strings. Selected ADME filters were employed to compel compounds having poor drug-like properties from this library. This library was converted to sdf and mol2 files by CONCORD 4.0, and was then docked to PPARgamma by DOCK 4.0 to identify new chemical entities that may be potential drug leads against type 2 diabetes and other metabolic diseases. The method to construct virtual combinatorial library using SMILES strings was further visualized by Visual Basic.net that can facilitate the needs of generating other type virtual combinatorial libraries.

Bioprospecting for Genes that Confer Biofuel Tolerance to Escherichia Coli Using a Genomic Library Approach

NASA Astrophysics Data System (ADS)

Tomko, Timothy

Microorganisms are capable of producing advanced biofuels that can be used as 'drop-in' alternatives to conventional liquid fuels. However, vital physiological processes and membrane properties are often disrupted by the presence of biofuel and limit the production yields. In order to make microbial biofuels a competitive fuel source, finding mechanisms for improving resistance to the toxic effects of biofuel production is vital. This investigation aims to identify resistance mechanisms from microorganisms that have evolved to withstand hydrocarbon-rich environments, such as those that thrive near natural oil seeps and in oil-polluted waters. First, using genomic DNA from Marinobacter aquaeolei, we constructed a transgenic library that we expressed in Escherichia coli. We exposed cells to inhibitory levels of pinene, a monoterpene that can serve as a jet fuel precursor with chemical properties similar to existing tactical fuels. Using a sequential strategy of a fosmid library followed by a plasmid library, we were able to isolate a region of DNA from the M. aquaeolei genome that conferred pinene tolerance when expressed in E. coli. We determined that a single gene, yceI, was responsible for the tolerance improvements. Overexpression of this gene placed no additional burden on the host. We also tested tolerance to other monoterpenes and showed that yceI selectively improves tolerance. Additionally, we used genomic DNA from Pseudomonas putida KT2440, which has innate solvent-tolerance properties, to create transgenic libraries in an E. coli host. We exposed cells containing the library to pinene, selecting for genes that improved tolerance. Importantly, we found that expressing the sigma factor RpoD from P. putida greatly expanded the diversity of tolerance genes recovered. With low expression of rpoDP. putida, we isolated a single pinene tolerance gene; with increased expression of the sigma factor our selection experiments returned multiple distinct tolerance mechanisms, including some that have been previously documented and also new mechanisms. Interestingly, high levels of rpoDP. putida, induction resulted in decreased diversity. We found that the tolerance levels provided by some genes are highly sensitive to the level of induction of rpoD P. putida,, while others provide tolerance across a wide range of rpoDP. putida, levels. This method for unlocking diversity in tolerance screening using heterologous sigma factor expression was applicable to both plasmid and fosmid-based transgenic libraries. These results suggest that by controlling the expression of appropriate heterologous sigma factors, we can greatly increase the searchable genomic space within transgenic libraries. This dissertation describes a method of effectively screening genomic DNA from multiple organisms for genes to mitigate biofuel stress and shows how tolerance genes can improve bacterial growth in the presence of toxic biofuel compounds. These identified genes can be targeted in future studies as candidates for use in biofuel production strains to increase biofuel yields.

EMMA: An Extensible Mammalian Modular Assembly Toolkit for the Rapid Design and Production of Diverse Expression Vectors.

PubMed

Martella, Andrea; Matjusaitis, Mantas; Auxillos, Jamie; Pollard, Steven M; Cai, Yizhi

2017-07-21

Mammalian plasmid expression vectors are critical reagents underpinning many facets of research across biology, biomedical research, and the biotechnology industry. Traditional cloning methods often require laborious manual design and assembly of plasmids using tailored sequential cloning steps. This process can be protracted, complicated, expensive, and error-prone. New tools and strategies that facilitate the efficient design and production of bespoke vectors would help relieve a current bottleneck for researchers. To address this, we have developed an extensible mammalian modular assembly kit (EMMA). This enables rapid and efficient modular assembly of mammalian expression vectors in a one-tube, one-step golden-gate cloning reaction, using a standardized library of compatible genetic parts. The high modularity, flexibility, and extensibility of EMMA provide a simple method for the production of functionally diverse mammalian expression vectors. We demonstrate the value of this toolkit by constructing and validating a range of representative vectors, such as transient and stable expression vectors (transposon based vectors), targeting vectors, inducible systems, polycistronic expression cassettes, fusion proteins, and fluorescent reporters. The method also supports simple assembly combinatorial libraries and hierarchical assembly for production of larger multigenetic cargos. In summary, EMMA is compatible with automated production, and novel genetic parts can be easily incorporated, providing new opportunities for mammalian synthetic biology.

Texas State Library: Library Services and Construction Act. Annual Report, FFY 1977.

ERIC Educational Resources Information Center

Texas State Library, Austin. Dept. of Library Development.

Texas State Library activities for 1977 which were funded under the Library Services and Construction Act (LSCA) are reported, including administrative expenses for LSCA; administrative tape conversion--to duplicate books recorded on open reel tapes to cassettes for use by the blind; continuing education and consulting for librarians; special…

Current and future resources for functional metagenomics.

PubMed

Lam, Kathy N; Cheng, Jiujun; Engel, Katja; Neufeld, Josh D; Charles, Trevor C

2015-01-01

Functional metagenomics is a powerful experimental approach for studying gene function, starting from the extracted DNA of mixed microbial populations. A functional approach relies on the construction and screening of metagenomic libraries-physical libraries that contain DNA cloned from environmental metagenomes. The information obtained from functional metagenomics can help in future annotations of gene function and serve as a complement to sequence-based metagenomics. In this Perspective, we begin by summarizing the technical challenges of constructing metagenomic libraries and emphasize their value as resources. We then discuss libraries constructed using the popular cloning vector, pCC1FOS, and highlight the strengths and shortcomings of this system, alongside possible strategies to maximize existing pCC1FOS-based libraries by screening in diverse hosts. Finally, we discuss the known bias of libraries constructed from human gut and marine water samples, present results that suggest bias may also occur for soil libraries, and consider factors that bias metagenomic libraries in general. We anticipate that discussion of current resources and limitations will advance tools and technologies for functional metagenomics research.

Identification and characterization of a chitin deacetylase from a metagenomic library of deep-sea sediments of the Arctic Ocean.

PubMed

Liu, Jinlin; Jia, Zhijuan; Li, Sha; Li, Yan; You, Qiang; Zhang, Chunyan; Zheng, Xiaotong; Xiong, Guomei; Zhao, Jin; Qi, Chao; Yang, Jihong

2016-09-15

The chemical and biological compositions of deep-sea sediments are interesting because of the underexplored diversity when it comes to bioprospecting. The special geographical location and climates make Arctic Ocean a unique ocean area containing an abundance of microbial resources. A metagenomic library was constructed based on the deep-sea sediments of Arctic Ocean. Part of insertion fragments of this library were sequenced. A chitin deacetylase gene, cdaYJ, was identified and characterized. A metagenomic library with 2750 clones was obtained and ten clones were sequenced. Results revealed several interesting genes, including a chitin deacetylase coding sequence, cdaYJ. The CdaYJ is homologous to some known chitin deacetylases and contains conserved chitin deacetylase active sites. CdaYJ protein exhibits a long N-terminal and a relative short C-terminal. Phylogenetic analysis revealed that CdaYJ showed highest homology to CDAs from Alphaproteobacteria. The cdaYJ gene was subcloned into the pET-28a vector and the recombinant CdaYJ (rCdaYJ) was expressed in Escherichia coli BL21 (DE3). rCdaYJ showed a molecular weight of 43kDa, and exhibited deacetylation activity by using p-nitroacetanilide as substrate. The optimal pH and temperature of rCdaYJ were tested as pH7.4 and 28°C, respectively. The construction of metagenomic library of the Arctic deep-sea sediments provides us an opportunity to look into the microbial communities and exploiting valuable gene resources. A chitin deacetylase CdaYJ was identified from the library. It showed highest deacetylation activity under slight alkaline and low temperature conditions. CdaYJ might be a candidate chitin deacetylase that possesses industrial and pharmaceutical potentials. Copyright © 2016 Elsevier B.V. All rights reserved.

Small RNA profiling reveals important roles for miRNAs in Arabidopsis response to Bacillus velezensis FZB42.

PubMed

Xie, Shanshan; Jiang, Haiyang; Xu, Zhilan; Xu, Qianqian; Cheng, Beijiu

2017-09-20

Bacillus velezensis FZB42 (previously classified as Bacillus amyloliquefaciens FZB42) has been confirmed to successfully colonize plant roots and enhance defense response against pathogen infection. This study indicated that FZB42 inoculation enhanced Arabidopsis defense response against Pseudomonas syringae DC3000 through inducing the expression of PR1, PDF1.2 and stomata closure. To further clarify the induced defense response at miRNA level, sRNA libraries from Arabidopsis roots inoculated with FZB42 and control were constructed and sequenced. The reads of 21nt and 24nt in length were the most abundant groups in FZB42-treated library and control library, respectively. 234 known miRNAs and 16 novel miRNAs were identified. Among them, 11 known miRNAs and 4 novel miRNAs were differentially expressed after FZB42 inoculation. Moreover cis-elements (TC-rich repeats, TCA-element and CGTCA-motif) associated with plant defense were also found in the promoters of these miRNAs. Additionally, 141 mRNAs were predicted as potential targets of these differentially expressed miRNAs. GO annotations of the target genes indicated their potential roles in polyamine biosynthetic process and intracellular protein transport biological process, which may contribute to increased defense response. Our findings indicated that Bacillus velezensis FZB42 inoculation altered the expression of Arabidopsis miRNAs and their target genes, which were associated with defense response. Copyright © 2017 Elsevier B.V. All rights reserved.

An optimized protocol for generation and analysis of Ion Proton sequencing reads for RNA-Seq.

PubMed

Yuan, Yongxian; Xu, Huaiqian; Leung, Ross Ka-Kit

2016-05-26

Previous studies compared running cost, time and other performance measures of popular sequencing platforms. However, comprehensive assessment of library construction and analysis protocols for Proton sequencing platform remains unexplored. Unlike Illumina sequencing platforms, Proton reads are heterogeneous in length and quality. When sequencing data from different platforms are combined, this can result in reads with various read length. Whether the performance of the commonly used software for handling such kind of data is satisfactory is unknown. By using universal human reference RNA as the initial material, RNaseIII and chemical fragmentation methods in library construction showed similar result in gene and junction discovery number and expression level estimated accuracy. In contrast, sequencing quality, read length and the choice of software affected mapping rate to a much larger extent. Unspliced aligner TMAP attained the highest mapping rate (97.27 % to genome, 86.46 % to transcriptome), though 47.83 % of mapped reads were clipped. Long reads could paradoxically reduce mapping in junctions. With reference annotation guide, the mapping rate of TopHat2 significantly increased from 75.79 to 92.09 %, especially for long (>150 bp) reads. Sailfish, a k-mer based gene expression quantifier attained highly consistent results with that of TaqMan array and highest sensitivity. We provided for the first time, the reference statistics of library preparation methods, gene detection and quantification and junction discovery for RNA-Seq by the Ion Proton platform. Chemical fragmentation performed equally well with the enzyme-based one. The optimal Ion Proton sequencing options and analysis software have been evaluated.

Microaspiration of esophageal gland cells and cDNA library construction for identifying parasitism genes of plant-parasitic nematodes.

PubMed

Hussey, Richard S; Huang, Guozhong; Allen, Rex

2011-01-01

Identifying parasitism genes encoding proteins secreted from a plant-parasitic nematode's esophageal gland cells and injected through its stylet into plant tissue is the key to understanding the molecular basis of nematode parasitism of plants. Parasitism genes have been cloned by directly microaspirating the cytoplasm from the esophageal gland cells of different parasitic stages of cyst or root-knot nematodes to provide mRNA to create a gland cell-specific cDNA library by long-distance reverse-transcriptase polymerase chain reaction. cDNA clones are sequenced and deduced protein sequences with a signal peptide for secretion are identified for high-throughput in situ hybridization to confirm gland-specific expression.

Construction and characterization of a bacterial artificial chromosome library for hexaploid wheat line 92R137

USDA-ARS?s Scientific Manuscript database

For map-based cloning of genes conferring important traits in the hexaploid wheat line 92R137, a bacterial artificial chromosome (BAC) library, including two sub libraries, was constructed using the genomic DNA of 92R137 digested with restriction enzymes HindIII and BamHI. The BAC library was compos...

Efficient preparation of shuffled DNA libraries through recombination (Gateway) cloning.

PubMed

Lehtonen, Soili I; Taskinen, Barbara; Ojala, Elina; Kukkurainen, Sampo; Rahikainen, Rolle; Riihimäki, Tiina A; Laitinen, Olli H; Kulomaa, Markku S; Hytönen, Vesa P

2015-01-01

Efficient and robust subcloning is essential for the construction of high-diversity DNA libraries in the field of directed evolution. We have developed a more efficient method for the subcloning of DNA-shuffled libraries by employing recombination cloning (Gateway). The Gateway cloning procedure was performed directly after the gene reassembly reaction, without additional purification and amplification steps, thus simplifying the conventional DNA shuffling protocols. Recombination-based cloning, directly from the heterologous reassembly reaction, conserved the high quality of the library and reduced the time required for the library construction. The described method is generally compatible for the construction of DNA-shuffled gene libraries. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

T-vector and in vivo recombination as tools to construct a large antibody library of breast cancer.

PubMed

Lv, Yong-Gang; Wang, Ting; Yuan, Shi-Fang; Li, Nan-Lin; Chen, Jiang-Hao; Zhao, Ai-Zhi; Ling, Rui; Wang, Ling

2010-06-01

The emergence of phage antibody libraries is an important advance in the field of antibody engineering. It provides a useful methodology to produce human antibodies and has the potential to replace traditional hybridoma technology. In our research, we used T-vector and in vivo recombination to construct a large antibody library from breast cancer patients. The use of T-vector considerably increased the cloning efficiency, and the diversity of the library could be increased easily using in vivo recombination. Taken together, a combination of these two techniques might be valuable in constructing a large antibody library.

Characterization of Transcriptional Complexity during Adipose Tissue Development in Bovines of Different Ages and Sexes

PubMed Central

Zhou, Yang; Sun, Jiajie; Li, Congjun; Wang, Yanhong; Li, Lan; Cai, Hanfang; Lan, Xianyong; Lei, Chuzhao; Zhao, Xin; Chen, Hong

2014-01-01

Background Adipose tissue has long been recognized to play an extremely important role in development. In bovines, it not only serves a fundamental function but also plays a key role in the quality of beef and, consequently, has drawn much public attention. Age and sex are two key factors that affect the development of adipose tissue, and there has not yet been a global study detailing the effects of these two factors on expressional differences of adipose tissues. Results In this study, total RNA from the back fat of fetal bovines, adult bulls, adult heifers and adult steers were used to construct libraries for Illumina next-generation sequencing. We detected the expression levels of 12,233 genes, with over 3,000 differently expressed genes when comparing fetal and adult patterns and an average of 1000 differently expressed genes when comparing adult patterns. Multiple Gene Ontology terms and pathways were found to be significantly enriched for these differentially expressed genes. Of the 12,233 detected genes, a total of 4,753 genes (38.85%) underwent alternative splicing events, and over 50% were specifically expressed in each library. Over 4,000 novel transcript units were discovered for one library, whereas only approximately 30% were considered to have coding ability, which supplied a large amount of information for the lncRNA study. Additionally, we detected 56,564 (fetal bovine), 65,154 (adult bull), 78,061 (adult heifer) and 86,965 (adult steer) putative single nucleotide polymorphisms located in coding regions of the four pooled libraries. Conclusion Here, we present, for the first time, a complete dataset involving the spatial and temporal transcriptome of bovine adipose tissue using RNA-seq. These data will facilitate the understanding of the effects of age and sex on the development of adipose tissue and supply essential information towards further studies on the genomes of beef cattle and other related mammals. PMID:24983926

Transcriptome Analysis of Gene Expression during Chinese Water Chestnut Storage Organ Formation

PubMed Central

Chen, Sainan; Wang, Yan; Yu, Meizhen; Chen, Xuehao; Li, Liangjun; Yin, Jingjing

2016-01-01

The product organ (storage organ; corm) of the Chinese water chestnut has become a very popular food in Asian countries because of its unique nutritional value. Corm formation is a complex biological process, and extensive whole genome analysis of transcripts during corm development has not been carried out. In this study, four corm libraries at different developmental stages were constructed, and gene expression was identified using a high-throughput tag sequencing technique. Approximately 4.9 million tags were sequenced, and 4,371,386, 4,372,602, 4,782,494, and 5,276,540 clean tags, including 119,676, 110,701, 100,089, and 101,239 distinct tags, respectively, were obtained after removal of low-quality tags from each library. More than 39% of the distinct tags were unambiguous and could be mapped to reference genes, while 40% were unambiguous tag-mapped genes. After mapping their functions in existing databases, a total of 11,592, 10,949, 10,585, and 7,111 genes were annotated from the B1, B2, B3, and B4 libraries, respectively. Analysis of the differentially expressed genes (DEGs) in B1/B2, B2/B3, and B3/B4 libraries showed that most of the DEGs at the B1/B2 stages were involved in carbohydrate and hormone metabolism, while the majority of DEGs were involved in energy metabolism and carbohydrate metabolism at the B2/B3 and B3/B4 stages. All of the upregulated transcription factors and 9 important genes related to product organ formation in the above four stages were also identified. The expression changes of nine of the identified DEGs were validated using a quantitative PCR approach. This study provides a comprehensive understanding of gene expression during corm formation in the Chinese water chestnut. PMID:27716802

Fabulous Facilities: New Constructions and Renovations.

ERIC Educational Resources Information Center

American Libraries, 1997

1997-01-01

Renovation and construction projects in 18 public and academic libraries across the United States are showcased, with 23 photographs illustrating library interiors and exteriors. Discussion centers on architecture, costs, technology infrastructure and equipment, preservation of old facilities, furniture, and library functions. (AEF)

Specific GFP-binding artificial proteins (αRep): a new tool for in vitro to live cell applications

PubMed Central

Chevrel, Anne; Urvoas, Agathe; de la Sierra-Gallay, Ines Li; Aumont-Nicaise, Magali; Moutel, Sandrine; Desmadril, Michel; Perez, Franck; Gautreau, Alexis; van Tilbeurgh, Herman; Minard, Philippe; Valerio-Lepiniec, Marie

2015-01-01

A family of artificial proteins, named αRep, based on a natural family of helical repeat was previously designed. αRep members are efficiently expressed, folded and extremely stable proteins. A large αRep library was constructed creating proteins with a randomized interaction surface. In the present study, we show that the αRep library is an efficient source of tailor-made specific proteins with direct applications in biochemistry and cell biology. From this library, we selected by phage display αRep binders with nanomolar dissociation constants against the GFP. The structures of two independent αRep binders in complex with the GFP target were solved by X-ray crystallography revealing two totally different binding modes. The affinity of the selected αReps for GFP proved sufficient for practically useful applications such as pull-down experiments. αReps are disulfide free proteins and are efficiently and functionally expressed in eukaryotic cells: GFP-specific αReps are clearly sequestrated by their cognate target protein addressed to various cell compartments. These results suggest that αRep proteins with tailor-made specificity can be selected and used in living cells to track, modulate or interfere with intracellular processes. PMID:26182430

Functional genomics to discover antibiotic resistance genes: The paradigm of resistance to colistin mediated by ethanolamine phosphotransferase in Shewanella algae MARS 14.

PubMed

Telke, Amar A; Rolain, Jean-Marc

2015-12-01

Shewanella algae MARS 14 is a colistin-resistant clinical isolate retrieved from bronchoalveolar lavage of a hospitalised patient. A functional genomics strategy was employed to discover the molecular support for colistin resistance in S. algae MARS 14. A pZE21 MCS-1 plasmid-based genomic expression library was constructed in Escherichia coli TOP10. The estimated library size was 1.30×10(8) bp. Functional screening of colistin-resistant clones was carried out on Luria-Bertani agar containing 8 mg/L colistin. Five colistin-resistant clones were obtained after complete screening of the genomic expression library. Analysis of DNA sequencing results found a unique gene in all selected clones. Amino acid sequence analysis of this unique gene using the Integrated Microbial Genomes (IMG) and KEGG databases revealed that this gene encodes ethanolamine phosphotransferase (EptA, or so-called PmrC). Reverse transcription PCR analysis indicated that resistance to colistin in S. algae MARS 14 was associated with overexpression of EptA (27-fold increase), which plays a crucial role in the arrangement of outer membrane lipopolysaccharide. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

High efficiency family shuffling based on multi-step PCR and in vivo DNA recombination in yeast: statistical and functional analysis of a combinatorial library between human cytochrome P450 1A1 and 1A2.

PubMed

Abécassis, V; Pompon, D; Truan, G

2000-10-15

The design of a family shuffling strategy (CLERY: Combinatorial Libraries Enhanced by Recombination in Yeast) associating PCR-based and in vivo recombination and expression in yeast is described. This strategy was tested using human cytochrome P450 CYP1A1 and CYP1A2 as templates, which share 74% nucleotide sequence identity. Construction of highly shuffled libraries of mosaic structures and reduction of parental gene contamination were two major goals. Library characterization involved multiprobe hybridization on DNA macro-arrays. The statistical analysis of randomly selected clones revealed a high proportion of chimeric genes (86%) and a homogeneous representation of the parental contribution among the sequences (55.8 +/- 2.5% for parental sequence 1A2). A microtiter plate screening system was designed to achieve colorimetric detection of polycyclic hydrocarbon hydroxylation by transformed yeast cells. Full sequences of five randomly picked and five functionally selected clones were analyzed. Results confirmed the shuffling efficiency and allowed calculation of the average length of sequence exchange and mutation rates. The efficient and statistically representative generation of mosaic structures by this type of family shuffling in a yeast expression system constitutes a novel and promising tool for structure-function studies and tuning enzymatic activities of multicomponent eucaryote complexes involving non-soluble enzymes.

Expression, Gene Cloning, and Characterization of Five Novel Phytases from Four Basidiomycete Fungi: Peniophora lycii, Agrocybe pediades, a Ceriporia sp., and Trametes pubescens

PubMed Central

Lassen, Søren F.; Breinholt, Jens; Østergaard, Peter R.; Brugger, Roland; Bischoff, Andrea; Wyss, Markus; Fuglsang, Claus C.

2001-01-01

Phytases catalyze the hydrolysis of phosphomonoester bonds of phytate (myo-inositol hexakisphosphate), thereby creating lower forms of myo-inositol phosphates and inorganic phosphate. In this study, cDNA expression libraries were constructed from four basidiomycete fungi (Peniophora lycii, Agrocybe pediades, a Ceriporia sp., and Trametes pubescens) and screened for phytase activity in yeast. One full-length phytase-encoding cDNA was isolated from each library, except for the Ceriporia sp. library where two different phytase-encoding cDNAs were found. All five phytases were expressed in Aspergillus oryzae, purified, and characterized. The phytases revealed temperature optima between 40 and 60°C and pH optima at 5.0 to 6.0, except for the P. lycii phytase, which has a pH optimum at 4.0 to 5.0. They exhibited specific activities in the range of 400 to 1,200 U · mg, of protein−1 and were capable of hydrolyzing phytate down to myo-inositol monophosphate. Surprisingly, 1H nuclear magnetic resonance analysis of the hydrolysis of phytate by all five basidiomycete phytases showed a preference for initial attack at the 6-phosphate group of phytic acid, a characteristic that was believed so far not to be seen with fungal phytases. Accordingly, the basidiomycete phytases described here should be grouped as 6-phytases (EC 3.1.3.26). PMID:11571175

L.S.C.A. Library Services & Construction Act Report for 1994. Information Partners for the 21st Century.

ERIC Educational Resources Information Center

Michigan Library, Lansing.

This annual report, consisting of 16 district summaries, demonstrates how federal Library Services and Construction Act (LSCA) funds have supported a wide range of 1994 projects to improve services in Michigan libraries. Most often these projects involved getting connected to the Internet, making the library accessible to the handicapped,…

Library Services and Construction Act (LSCA). South Carolina State-Administration Annual Program, 1992-1993.

ERIC Educational Resources Information Center

South Carolina State Library, Columbia.

Supporting documentation for the grant and use of Federal Library Services and Construction Act (LSCA) funds in South Carolina is presented in this annual program. Under Title I, Library Services, the bulk of the grant money is planned for the following projects: (1) general administration (Project I-A); (2) library interpretation (Project I-B);…

Library Services and Construction Act (LSCA). Texas State-Administered Annual Program FY 1993.

ERIC Educational Resources Information Center

Texas State Library, Austin. Dept. of Library Development.

The documentation required under the Federal Library Services and Construction Act for the 1993 annual program of the Texas State Library is assembled. Under Title I, Public Library Services to Areas Without Services, the state plans total expenditures of $12,066,877, including $5,019,151 in federal funds and $7,047,726 in state funds for services…

Current and future resources for functional metagenomics

PubMed Central

Lam, Kathy N.; Cheng, Jiujun; Engel, Katja; Neufeld, Josh D.; Charles, Trevor C.

2015-01-01

Functional metagenomics is a powerful experimental approach for studying gene function, starting from the extracted DNA of mixed microbial populations. A functional approach relies on the construction and screening of metagenomic libraries—physical libraries that contain DNA cloned from environmental metagenomes. The information obtained from functional metagenomics can help in future annotations of gene function and serve as a complement to sequence-based metagenomics. In this Perspective, we begin by summarizing the technical challenges of constructing metagenomic libraries and emphasize their value as resources. We then discuss libraries constructed using the popular cloning vector, pCC1FOS, and highlight the strengths and shortcomings of this system, alongside possible strategies to maximize existing pCC1FOS-based libraries by screening in diverse hosts. Finally, we discuss the known bias of libraries constructed from human gut and marine water samples, present results that suggest bias may also occur for soil libraries, and consider factors that bias metagenomic libraries in general. We anticipate that discussion of current resources and limitations will advance tools and technologies for functional metagenomics research. PMID:26579102

A Diversity-Oriented Library of Fluorophore-Modified Receptors Constructed from a Chemical Library of Synthetic Fluorophores.

PubMed

Nakano, Shun; Tamura, Tomoki; Das, Raj Kumar; Nakata, Eiji; Chang, Young-Tae; Morii, Takashi

2017-11-16

The practical application of biosensors can be determined by evaluating the sensing ability of fluorophore-modified derivatives of a receptor with appropriate recognition characteristics for target molecules. One of the key determinants for successfully obtaining a useful biosensor is wide variation in the fluorophores attached to a given receptor. Thus, using a larger fluorophore-modified receptor library provides a higher probability of obtaining a practically useful biosensor. However, no effective method has yet been developed for constructing such a diverse library of fluorophore-modified receptors. Herein, we report a method for constructing fluorophore-modified receptors by using a chemical library of synthetic fluorophores with a thiol-reactive group. This library was converted into a library of fluorophore-modified adenosine-binding ribonucleopeptide (RNP) receptors by introducing the fluorophores to the Rev peptide of the RNP complex by alkylation of the thiol group. This method enabled the construction of 263 fluorophore-modified ATP-binding RNP receptors and allowed the selection of suitable receptor-based fluorescent sensors that target ATP. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Health sciences library building projects: 1994 survey.

PubMed Central

Ludwig, L

1995-01-01

Designing and building new or renovated space is time consuming and requires politically sensitive discussions concerning a number of both long-term and immediate planning issues. The Medical Library Association's fourth annual survey of library building projects identified ten health sciences libraries that are planning, expanding, or constructing new facilities. Two projects are in predesign stages, four represent new construction, and four involve renovations to existing libraries. The Texas Medical Association Library, the King Faisal Specialist Hospital and Research Centre Library, and the Northwestern University Galter Health Sciences Library illustrate how these libraries are being designed for the future and take into account areas of change produced by new information technologies, curricular trends, and new ways to deliver library services. Images PMID:7599586

Partial characterization of normal and Haemophilus influenzae-infected mucosal complementary DNA libraries in chinchilla middle ear mucosa.

PubMed

Kerschner, Joseph E; Erdos, Geza; Hu, Fen Ze; Burrows, Amy; Cioffi, Joseph; Khampang, Pawjai; Dahlgren, Margaret; Hayes, Jay; Keefe, Randy; Janto, Benjamin; Post, J Christopher; Ehrlich, Garth D

2010-04-01

We sought to construct and partially characterize complementary DNA (cDNA) libraries prepared from the middle ear mucosa (MEM) of chinchillas to better understand pathogenic aspects of infection and inflammation, particularly with respect to leukotriene biogenesis and response. Chinchilla MEM was harvested from controls and after middle ear inoculation with nontypeable Haemophilus influenzae. RNA was extracted to generate cDNA libraries. Randomly selected clones were subjected to sequence analysis to characterize the libraries and to provide DNA sequence for phylogenetic analyses. Reverse transcription-polymerase chain reaction of the RNA pools was used to generate cDNA sequences corresponding to genes associated with leukotriene biosynthesis and metabolism. Sequence analysis of 921 randomly selected clones from the uninfected MEM cDNA library produced approximately 250,000 nucleotides of almost entirely novel sequence data. Searches of the GenBank database with the Basic Local Alignment Search Tool provided for identification of 515 unique genes expressed in the MEM and not previously described in chinchillas. In almost all cases, the chinchilla cDNA sequences displayed much greater homology to human or other primate genes than with rodent species. Genes associated with leukotriene metabolism were present in both normal and infected MEM. Based on both phylogenetic comparisons and gene expression similarities with humans, chinchilla MEM appears to be an excellent model for the study of middle ear inflammation and infection. The higher degree of sequence similarity between chinchillas and humans compared to chinchillas and rodents was unexpected. The cDNA libraries from normal and infected chinchilla MEM will serve as useful molecular tools in the study of otitis media and should yield important information with respect to middle ear pathogenesis.

Partial Characterization of Normal and Haemophilus influenzae–Infected Mucosal Complementary DNA Libraries in Chinchilla Middle Ear Mucosa

PubMed Central

Kerschner, Joseph E.; Erdos, Geza; Hu, Fen Ze; Burrows, Amy; Cioffi, Joseph; Khampang, Pawjai; Dahlgren, Margaret; Hayes, Jay; Keefe, Randy; Janto, Benjamin; Post, J. Christopher; Ehrlich, Garth D.

2010-01-01

Objectives We sought to construct and partially characterize complementary DNA (cDNA) libraries prepared from the middle ear mucosa (MEM) of chinchillas to better understand pathogenic aspects of infection and inflammation, particularly with respect to leukotriene biogenesis and response. Methods Chinchilla MEM was harvested from controls and after middle ear inoculation with nontypeable Haemophilus influenzae. RNA was extracted to generate cDNA libraries. Randomly selected clones were subjected to sequence analysis to characterize the libraries and to provide DNA sequence for phylogenetic analyses. Reverse transcription–polymerase chain reaction of the RNA pools was used to generate cDNA sequences corresponding to genes associated with leukotriene biosynthesis and metabolism. Results Sequence analysis of 921 randomly selected clones from the uninfected MEM cDNA library produced approximately 250,000 nucleotides of almost entirely novel sequence data. Searches of the GenBank database with the Basic Local Alignment Search Tool provided for identification of 515 unique genes expressed in the MEM and not previously described in chinchillas. In almost all cases, the chinchilla cDNA sequences displayed much greater homology to human or other primate genes than with rodent species. Genes associated with leukotriene metabolism were present in both normal and infected MEM. Conclusions Based on both phylogenetic comparisons and gene expression similarities with humans, chinchilla MEM appears to be an excellent model for the study of middle ear inflammation and infection. The higher degree of sequence similarity between chinchillas and humans compared to chinchillas and rodents was unexpected. The cDNA libraries from normal and infected chinchilla MEM will serve as useful molecular tools in the study of otitis media and should yield important information with respect to middle ear pathogenesis. PMID:20433028

Characterization and comparative profiling of the small RNA transcriptomes in the Hemipteran insect Nilaparvata lugens.

PubMed

Zha, Wenjun; Zhou, Lei; Li, Sanhe; Liu, Kai; Yang, Guocai; Chen, Zhijun; Liu, Kai; Xu, Huashan; Li, Peide; Hussain, Saddam; You, Aiqing

2016-12-20

MicroRNAs (miRNAs) are a group of small RNAs involved in various biological processes through negative regulation of mRNAs at the post-transcriptional level. The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the most serious and destructive insect pests of rice. In the present study, two small RNA libraries of virulent N. lugens populations (Biotype I survives on susceptive rice variety TN1 and Biotype Y survives on moderately resistant rice variety YHY15) were constructed and sequenced using the high-throughput sequencing technology in order to identify the relationship between miRNAs of N.lugens and adaptation of BPH pests to rice resistance. In total 15,758,632 and 11,442,592 reads, corresponding to 3,144,026 and 2,550,049 unique sequences, were obtained in the two libraries (BPH-TN1 and BPH-YHY15 libraries), respectively. A total of 41 potential novel miRNAs were predicted in the two libraries, and 26 miRNAs showed significantly differential expression between two libraries. All miRNAs were significantly up-regulated in the BPH-TN1 library. Target genes likely regulated by these differentially expressed miRNAs were predicted using computational prediction. The functional annotation of target genes performed by Gene Ontology enrichment (GO) and Kyoto Encyclopedia of Genes and Genomes pathway analysis (KEGG) indicated that a majority of differential miRNAs were involved in "Metabolism" pathway. These results provided an understanding of the role of miRNAs in BPH to adaptability of BPH on rice resistance, and will be useful in developing new control strategies for host defense against BPH. Copyright © 2016 Elsevier B.V. All rights reserved.

A fusion-protein approach enabling mammalian cell production of tumor targeting protein domains for therapeutic development.

PubMed

Hu, Jia; Chen, Xiang; Zhang, Xuhua; Yuan, Xiaopeng; Yang, Mingjuan; Dai, Hui; Yang, Wei; Zhou, Qinghua; Wen, Weihong; Wang, Qirui; Qin, Weijun; Zhao, Aizhi

2018-05-01

A single chain Fv fragment (scFv) is a fusion of the variable regions of heavy (V H ) and light (V L ) chains of immunoglobulins. They are important elements of chimeric antigen receptors for cancer therapy. We sought to produce a panel of 16 extracellular protein domains of tumor markers for use in scFv yeast library screenings. A series of vectors comprising various combinations of expression elements was made, but expression was unpredictable and more than half of the protein domains could not be produced using any of the constructs. Here we describe a novel fusion expression system based on mouse TEM7 (tumor endothelial marker 7), which could facilitate protein expression. With this approach we could produce all but one of the tumor marker domains that could not otherwise be expressed. In addition, we demonstrated that the tumor associated antigen hFZD10 produced as a fusion protein with mTEM7 could be used to enrich scFv antibodies from a yeast display library. Collectively our study demonstrates the potential of specific fusion proteins based on mTEM7 in enabling mammalian cell production of tumor targeting protein domains for therapeutic development. © 2018 The Protein Society.

Construction and analysis of the cDNA subtraction library of yeast and mycelial phases of Sporothrix globosa isolated in China: identification of differentially expressed genes*

PubMed Central

Hu, Qing-bi; He, Yu; Zhou, Xun

2015-01-01

Species included in the Sporothrix schenckii complex are temperature-dependent with dimorphic growth and cause sporotrichosis that is characterized by chronic and fatal lymphocutaneous lesions. The putative species included in the Sporothrix complex are S. brasiliensis, S. globosa, S. mexicana, S. pallida, S. schenckii, and S. lurei. S. globosa is the causal agent of sporotrichosis in China, and its pathogenicity appears to be closely related to the dimorphic transition, i.e. from the mycelial to the yeast phase, it adapts to changing environmental conditions. To determine the molecular mechanisms of the switching process that mediates the dimorphic transition of S. globosa, suppression subtractive hybridization (SSH) was used to prepare a complementary DNA (cDNA) subtraction library from the yeast and mycelial phases. Bioinformatics analysis was performed to profile the relationship between differently expressed genes and the dimorphic transition. Two genes that were expressed at higher levels by the yeast form were selected, and their differential expression levels were verified using a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). It is believed that these differently expressed genes are involved in the pathogenesis of S. globosa infection in China. PMID:26642182

Construction of a scFv Library with Synthetic, Non-combinatorial CDR Diversity.

PubMed

Bai, Xuelian; Shim, Hyunbo

2017-01-01

Many large synthetic antibody libraries have been designed, constructed, and successfully generated high-quality antibodies suitable for various demanding applications. While synthetic antibody libraries have many advantages such as optimized framework sequences and a broader sequence landscape than natural antibodies, their sequence diversities typically are generated by random combinatorial synthetic processes which cause the incorporation of many undesired CDR sequences. Here, we describe the construction of a synthetic scFv library using oligonucleotide mixtures that contain predefined, non-combinatorially synthesized CDR sequences. Each CDR is first inserted to a master scFv framework sequence and the resulting single-CDR libraries are subjected to a round of proofread panning. The proofread CDR sequences are assembled to produce the final scFv library with six diversified CDRs.

Development of High Throughput Process for Constructing 454 Titanium and Illumina Libraries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deshpande, Shweta; Hack, Christopher; Tang, Eric

2010-05-28

We have developed two processes with the Biomek FX robot to construct 454 titanium and Illumina libraries in order to meet the increasing library demands. All modifications in the library construction steps were made to enable the adaptation of the entire processes to work with the 96-well plate format. The key modifications include the shearing of DNA with Covaris E210 and the enzymatic reaction cleaning and fragment size selection with SPRI beads and magnetic plate holders. The construction of 96 Titanium libraries takes about 8 hours from sheared DNA to ssDNA recovery. The processing of 96 Illumina libraries takes lessmore » time than that of the Titanium library process. Although both processes still require manual transfer of plates from robot to other work stations such as thermocyclers, these robotic processes represent about 12- to 24-folds increase of library capacity comparing to the manual processes. To enable the sequencing of many libraries in parallel, we have also developed sets of molecular barcodes for both library types. The requirements for the 454 library barcodes include 10 bases, 40-60percent GC, no consecutive same base, and no less than 3 bases difference between barcodes. We have used 96 of the resulted 270 barcodes to construct libraries and pool to test the ability of accurately assigning reads to the right samples. When allowing 1 base error occurred in the 10 base barcodes, we could assign 99.6percent of the total reads and 100percent of them were uniquely assigned. As for the Illumina barcodes, the requirements include 4 bases, balanced GC, and at least 2 bases difference between barcodes. We have begun to assess the ability to assign reads after pooling different number of libraries. We will discuss the progress and the challenges of these scale-up processes.« less

Immune-Related Transcriptome of Coptotermes formosanus Shiraki Workers: The Defense Mechanism

PubMed Central

Hussain, Abid; Li, Yi-Feng; Cheng, Yu; Liu, Yang; Chen, Chuan-Cheng; Wen, Shuo-Yang

2013-01-01

Formosan subterranean termites, Coptotermes formosanus Shiraki, live socially in microbial-rich habitats. To understand the molecular mechanism by which termites combat pathogenic microbes, a full-length normalized cDNA library and four Suppression Subtractive Hybridization (SSH) libraries were constructed from termite workers infected with entomopathogenic fungi (Metarhizium anisopliae and Beauveria bassiana), Gram-positive Bacillus thuringiensis and Gram-negative Escherichia coli, and the libraries were analyzed. From the high quality normalized cDNA library, 439 immune-related sequences were identified. These sequences were categorized as pattern recognition receptors (47 sequences), signal modulators (52 sequences), signal transducers (137 sequences), effectors (39 sequences) and others (164 sequences). From the SSH libraries, 27, 17, 22 and 15 immune-related genes were identified from each SSH library treated with M. anisopliae, B. bassiana, B. thuringiensis and E. coli, respectively. When the normalized cDNA library was compared with the SSH libraries, 37 immune-related clusters were found in common; 56 clusters were identified in the SSH libraries, and 259 were identified in the normalized cDNA library. The immune-related gene expression pattern was further investigated using quantitative real time PCR (qPCR). Important immune-related genes were characterized, and their potential functions were discussed based on the integrated analysis of the results. We suggest that normalized cDNA and SSH libraries enable us to discover functional genes transcriptome. The results remarkably expand our knowledge about immune-inducible genes in C. formosanus Shiraki and enable the future development of novel control strategies for the management of Formosan subterranean termites. PMID:23874972

Construction of an agglutination tool: recombinant Fab fragments biotinylated in vitro.

PubMed

Czerwinski, Marcin; Krop-Watorek, Anna; Wasniowska, Kazimiera; Smolarek, Dorota; Spitalnik, Steven L

2009-11-30

The pComb3H vector system is used for constructing and panning recombinant antibody libraries. It allows for expression of monovalent Fab fragments, either on the surface of M13 phage, or in the form of soluble proteins secreted into the periplasmic space of bacteria. We constructed a modified pComb3H vector containing cDNA encoding for a 23-amino acid fragment of the Escherichia coli biotin carboxy carrier protein (BCCP), which is an acceptor sequence for biotinylation. The vector was used to express the Fab fragment recognizing human glycophorin A. The purified Fab fragment containing this biotin acceptor sequence was effectively biotinylated in vitro using biotin ligase (BirA). The specificity and avidity of the biotinylated Fab fragments were similar to the previously produced, unmodified Fab fragments. An avidin-alkaline phosphatase conjugate was used to detect the recombinant Fab fragments, instead of secondary antibody. In addition, when biotinylated Fab fragments were mixed with avidin, red blood cells were directly agglutinated.

Mining the metagenome of activated biomass of an industrial wastewater treatment plant by a novel method.

PubMed

Sharma, Nandita; Tanksale, Himgouri; Kapley, Atya; Purohit, Hemant J

2012-12-01

Metagenomic libraries herald the era of magnifying the microbial world, tapping into the vast metabolic potential of uncultivated microbes, and enhancing the rate of discovery of novel genes and pathways. In this paper, we describe a method that facilitates the extraction of metagenomic DNA from activated sludge of an industrial wastewater treatment plant and its use in mining the metagenome via library construction. The efficiency of this method was demonstrated by the large representation of the bacterial genome in the constructed metagenomic libraries and by the functional clones obtained. The BAC library represented 95.6 times the bacterial genome, while, the pUC library represented 41.7 times the bacterial genome. Twelve clones in the BAC library demonstrated lipolytic activity, while four clones demonstrated dioxygenase activity. Four clones in pUC library tested positive for cellulase activity. This method, using FTA cards, not only can be used for library construction, but can also store the metagenome at room temperature.

Screening for single-chain variable fragment antibodies against multiple Cry1 toxins from an immunized mouse phage display antibody library.

PubMed

Dong, Sa; Bo, Zongyi; Zhang, Cunzheng; Feng, Jianguo; Liu, Xianjin

2018-04-01

Single-chain variable fragment (scFv) is a kind of antibody that possess only one chain of the complete antibody while maintaining the antigen-specific binding abilities and can be expressed in prokaryotic system. In this study, scFvs against Cry1 toxins were screened out from an immunized mouse phage displayed antibody library, which was successfully constructed with capacity of 6.25 × 10 7  CFU/mL. Using the mixed and alternative antigen coating strategy and after four rounds of affinity screening, seven positive phage-scFvs against Cry1 toxins were selected and characterized. Among them, clone scFv-3H9 (MG214869) showing relative stable and high binding abilities to six Cry1 toxins was selected for expression and purification. SDS-PAGE indicated that the scFv-3H9 fragments approximately 27 kDa were successfully expressed in Escherichia coli HB2151 strain. The purified scFv-3H9 was used to establish the double antibody sandwich enzyme-linked immunosorbent assay method (DAS-ELISA) for detecting six Cry1 toxins, of which the lowest detectable limits (LOD) and the lowest quantitative limits (LOQ) were 3.14-11.07 and 8.22-39.44 ng mL -1 , respectively, with the correlation coefficient higher than 0.997. The average recoveries of Cry1 toxins from spiked rice leaf samples were ranged from 84 to 95%, with coefficient of variation (CV) less than 8.2%, showing good accuracy for the multi-residue determination of six Cry1 toxins in agricultural samples. This research suggested that the constructed phage display antibody library based on the animal which was immunized with the mixture of several antigens under the same category can be used for the quick and effective screening of generic antibodies.

LSCA Builds Michigan Libraries.

ERIC Educational Resources Information Center

Michigan Library, Lansing.

This report highlights 19 of the 48 recently completed public library construction projects in Michigan which received partial funding from the 1983 Emergency Jobs Act. The grants were administered under Title II of the Library Services and Construction Act (LSCA). Introductory material includes listings of the State of Michigan Legislative…

Microsatellite DNA library for Caiman latirostris.

PubMed

Zucoloto, Rodrigo Barban; Verdade, Luciano Martins; Coutinho, Luiz Lehmann

2002-12-15

New genetic markers were characterized for the broad-snouted caiman (Caiman latirostris) by constructing libraries enriched for microsatellite DNA. Construction and characterization of these libraries are described in the present study. One microsatellite marker was developed from a (ACC-TGG)(n)enriched microsatellite DNA library, and 12 microsatellite markers were developed from a (AC-TG)(n)enriched microsatellite DNA library. These markers were tested in wild-caught animals, and these tests resulted in ten new polymorphic microsatellites for C. latirostris. Copyright 2002 Wiley-Liss, Inc.

Sequence evaluation of four specific cDNA libraries for developmental genomics of sunflower.

PubMed

Tamborindeguy, C; Ben, C; Liboz, T; Gentzbittel, L

2004-04-01

Four different cDNA libraries were constructed from sunflower protoplasts growing under embryogenic and non-embryogenic conditions: one standard library from each condition and two subtractive libraries in opposite sense. A total of 22,876 cDNA clones were obtained and 4800 ESTs were sequenced, giving rise to 2479 high quality ESTs representing an unigene set of 1502 sequences. This set was compared with ESTs represented in public databases using the programs BLASTN and BLASTX, and its members were classified according to putative function using the catalog in the Kyoto Encyclopedia of Genes and Genomes (KEGG). Some 33% of sequences failed to align with existing plant ESTs and therefore represent putative novel genes. The libraries show a low level of redundancy and, on average, 50% of the present ESTs have not been previously reported for sunflower. Several potentially interesting genes were identified, based on their homology with genes involved in animal zygotic division or plant embryogenesis. We also identified two ESTs that show significantly different levels of expression under embryogenic and non-embryogenic conditions. The libraries described here represent an original and valuable resource for the discovery of yet unknown genes putatively involved in dicot embryogenesis and improving our knowledge of the mechanisms involved in polarity acquisition by plant embryos.

Method for construction of normalized cDNA libraries

DOEpatents

Soares, Marcelo B.; Efstratiadis, Argiris

1998-01-01

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to appropriate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. This invention also provides normalized cDNA libraries generated by the above-described method and uses of the generated libraries.

Method for construction of normalized cDNA libraries

DOEpatents

Soares, M.B.; Efstratiadis, A.

1998-11-03

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3` noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to appropriate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. This invention also provides normalized cDNA libraries generated by the above-described method and uses of the generated libraries. 19 figs.

The Use of EST Expression Matrixes for the Quality Control of Gene Expression Data

PubMed Central

Milnthorpe, Andrew T.; Soloviev, Mikhail

2012-01-01

EST expression profiling provides an attractive tool for studying differential gene expression, but cDNA libraries' origins and EST data quality are not always known or reported. Libraries may originate from pooled or mixed tissues; EST clustering, EST counts, library annotations and analysis algorithms may contain errors. Traditional data analysis methods, including research into tissue-specific gene expression, assume EST counts to be correct and libraries to be correctly annotated, which is not always the case. Therefore, a method capable of assessing the quality of expression data based on that data alone would be invaluable for assessing the quality of EST data and determining their suitability for mRNA expression analysis. Here we report an approach to the selection of a small generic subset of 244 UniGene clusters suitable for identification of the tissue of origin for EST libraries and quality control of the expression data using EST expression information alone. We created a small expression matrix of UniGene IDs using two rounds of selection followed by two rounds of optimisation. Our selection procedures differ from traditional approaches to finding “tissue-specific” genes and our matrix yields consistency high positive correlation values for libraries with confirmed tissues of origin and can be applied for tissue typing and quality control of libraries as small as just a few hundred total ESTs. Furthermore, we can pick up tissue correlations between related tissues e.g. brain and peripheral nervous tissue, heart and muscle tissues and identify tissue origins for a few libraries of uncharacterised tissue identity. It was possible to confirm tissue identity for some libraries which have been derived from cancer tissues or have been normalised. Tissue matching is affected strongly by cancer progression or library normalisation and our approach may potentially be applied for elucidating the stage of normalisation in normalised libraries or for cancer staging. PMID:22412959

Analysis of differentially expressed genes between fluoride-sensitive and fluoride-endurable individuals in midgut of silkworm, Bombyx mori.

PubMed

Qian, Heying; Li, Gang; He, Qingling; Zhang, Huaguang; Xu, Anying

2016-08-15

Fluoride tolerance is an economically important trait of silkworm. Near-isogenic lines (NILs) of the dominant endurance to fluoride (Def) gene in Bombyx mori has been constructed before. Here, we analyzed the gene expression profiles of midgut of fluoride-sensitive and fluoride-endurable individuals of Def NILs by using high-throughput Illumina sequencing technology and bioinformatics tools, and identified differentially expressed genes between these individuals. A total of 3,612,399 and 3,567,631 clean tags for the libraries of fluoride-endurable and fluoride-sensitive individuals were obtained, which corresponded to 32,933 and 43,976 distinct clean tags, respectively. Analysis of differentially expressed genes indicates that 241 genes are differentially expressed between the two libraries. Among the 241 genes, 30 are up-regulated and 211 are down-regulated in fluoride-endurable individuals. Pathway enrichment analysis demonstrates that genes related to ribosomes, pancreatic secretion, steroid biosynthesis, glutathione metabolism, steroid biosynthesis, and glycerolipid metabolism are down-regulated in fluoride-endurable individuals. qRT-PCR was conducted to confirm the results of the DGE. The present study analyzed differential expression of related genes and tried to find out whether the crucial genes were related to fluoride detoxification which might elucidate fluoride effect and provide a new way in the fluorosis research. Copyright © 2016 Elsevier B.V. All rights reserved.

Preservation Concerns in Construction and Remodeling of Libraries: Planning for Preservation.

ERIC Educational Resources Information Center

Trinkley, Michael

To help libraries and other holdings institutions better incorporate preservation concerns in construction, renovation, and routine maintenance, various techniques are presented that allow preservation concerns to be integrated. The following topics are considered: (1) site selection; (2) design of the building envelope; (3) the library interior;…

The Construction of Infrastructure for Library's Digital Document Telecommunications.

ERIC Educational Resources Information Center

Changxing, Ying; Zuzao, Lin

This paper discusses the construction of the infrastructure for libraries' digital document telecommunications. The first section describes the topologies of the library LAN (Local Area Network) cabling system, including the main characteristics of the LAN and three classical topologies typically used with LANs, i.e., the bus, star, and ring…

Differentially expressed genes of Coptotermes formosanus (Isoptera: Rhinotermitidae) challenged by chemical insecticides.

PubMed

Zhang, Yi; Zhao, Yuanyuan; Qiu, Xuehong; Han, Richou

2013-08-01

Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) termites are harmful social insects to wood constructions. The current control methods heavily depend on the chemical insecticides with increasing resistance. Analysis of the differentially expressed genes mediated by chemical insecticides will contribute to the understanding of the termite resistance to chemicals and to the establishment of alternative control measures. In the present article, a full-length cDNA library was constructed from the termites induced by a mixture of commonly used insecticides (0.01% sulfluramid and 0.01% triflumuron) for 24 h, by using the RNA ligase-mediated Rapid Amplification cDNA End method. Fifty-eight differentially expressed clones were obtained by polymerase chain reaction and confirmed by dot-blot hybridization. Forty-six known sequences were obtained, which clustered into 33 unique sequences grouped in 6 contigs and 27 singlets. Sixty-seven percent (22) of the sequences had counterpart genes from other organisms, whereas 33% (11) were undescribed. A Gene Ontology analysis classified 33 unique sequences into different functional categories. In general, most of the differential expression genes were involved in binding and catalytic activity.

cDNA library construction of two human Demodexspecies.

PubMed

Niu, DongLing; Wang, RuiLing; Zhao, YaE; Yang, Rui; Hu, Li; Lei, YuYang; Dan, WeiChao

2017-06-01

The research of Demodex, a type of pathogen causing various dermatoses in animals and human beings, is lacking at RNA level. This study aims at extracting RNA and constructing cDNA library for Demodex. First, P. cuniculiand D. farinaewere mixed to establish homogenization method for RNA extraction. Second, D. folliculorumand D. breviswere collected and preserved in Trizol, which were mixed with D. farinaerespectively to extract RNA. Finally, cDNA library was constructed and its quality was assessed. The results indicated that for D. folliculorum& D. farinae, the recombination rate of cDNA library was 90.67% and the library titer was 7.50 × 104 pfu/ml. 17 of the 59 positive clones were predicted to be of D. folliculorum; For D. brevis& D. farinae, the recombination rate was 90.96% and the library titer was 7.85 x104 pfu/ml. 40 of the 59 positive clones were predicted to be of D. brevis. Further detection by specific primers demonstrated that mtDNA cox1, cox3and ATP6 detected from cDNA libraries had 96.52%-99.73% identities with the corresponding sequences in GenBank. In conclusion, the cDNA libraries constructed for Demodexmixed with D. farinaewere successful and could satisfy the requirements for functional genes detection.

Development of EST-SSR markers for Elaeocarpus photiniifolia (Elaeocarpaceae), an endemic taxon of the Bonin Islands.

PubMed

Sugai, Kyoko; Setsuko, Suzuki; Uchiyama, Kentaro; Murakami, Noriaki; Kato, Hidetoshi; Yoshimaru, Hiroshi

2012-02-01

Expressed sequence tag (EST)-derived microsatellite markers were developed for Elaeocarpus photiniifolia, an endemic taxon of the Bonin Islands. Initially, a complementary DNA (cDNA) library was constructed by de novo pyrosequencing of total RNA extracted from a seedling. A total of 267 primer pairs were designed from the library. Of the 48 tested loci, 25 loci were polymorphic among 41 individuals representing the entire geographical range of the species, with the number of alleles per locus and expected heterozygosity ranging from two to 14 and 0.09 to 0.86, respectively. Most loci were transferable to a related species, E. sylvestris. The developed markers will be useful for evaluating the genetic structure of E. photiniifolia.

Next-generation sequencing library construction on a surface.

PubMed

Feng, Kuan; Costa, Justin; Edwards, Jeremy S

2018-05-30

Next-generation sequencing (NGS) has revolutionized almost all fields of biology, agriculture and medicine, and is widely utilized to analyse genetic variation. Over the past decade, the NGS pipeline has been steadily improved, and the entire process is currently relatively straightforward. However, NGS instrumentation still requires upfront library preparation, which can be a laborious process, requiring significant hands-on time. Herein, we present a simple but robust approach to streamline library preparation by utilizing surface bound transposases to construct DNA libraries directly on a flowcell surface. The surface bound transposases directly fragment genomic DNA while simultaneously attaching the library molecules to the flowcell. We sequenced and analysed a Drosophila genome library generated by this surface tagmentation approach, and we showed that our surface bound library quality was comparable to the quality of the library from a commercial kit. In addition to the time and cost savings, our approach does not require PCR amplification of the library, which eliminates potential problems associated with PCR duplicates. We described the first study to construct libraries directly on a flowcell. We believe our technique could be incorporated into the existing Illumina sequencing pipeline to simplify the workflow, reduce costs, and improve data quality.

Comparative characterization of random-sequence proteins consisting of 5, 12, and 20 kinds of amino acids

PubMed Central

Tanaka, Junko; Doi, Nobuhide; Takashima, Hideaki; Yanagawa, Hiroshi

2010-01-01

Screening of functional proteins from a random-sequence library has been used to evolve novel proteins in the field of evolutionary protein engineering. However, random-sequence proteins consisting of the 20 natural amino acids tend to aggregate, and the occurrence rate of functional proteins in a random-sequence library is low. From the viewpoint of the origin of life, it has been proposed that primordial proteins consisted of a limited set of amino acids that could have been abundantly formed early during chemical evolution. We have previously found that members of a random-sequence protein library constructed with five primitive amino acids show high solubility (Doi et al., Protein Eng Des Sel 2005;18:279–284). Although such a library is expected to be appropriate for finding functional proteins, the functionality may be limited, because they have no positively charged amino acid. Here, we constructed three libraries of 120-amino acid, random-sequence proteins using alphabets of 5, 12, and 20 amino acids by preselection using mRNA display (to eliminate sequences containing stop codons and frameshifts) and characterized and compared the structural properties of random-sequence proteins arbitrarily chosen from these libraries. We found that random-sequence proteins constructed with the 12-member alphabet (including five primitive amino acids and positively charged amino acids) have higher solubility than those constructed with the 20-member alphabet, though other biophysical properties are very similar in the two libraries. Thus, a library of moderate complexity constructed from 12 amino acids may be a more appropriate resource for functional screening than one constructed from 20 amino acids. PMID:20162614

Characterization of resistance to pine wood nematode infection in Pinus thunbergii using suppression subtractive hybridization.

PubMed

Hirao, Tomonori; Fukatsu, Eitaro; Watanabe, Atsushi

2012-01-24

Pine wilt disease is caused by the pine wood nematode, Bursaphelenchus xylophilus, which threatens pine forests and forest ecosystems worldwide and causes serious economic losses. In the 40 years since the pathogen was identified, the physiological changes occurring as the disease progresses have been characterized using anatomical and biochemical methods, and resistant trees have been selected via breeding programs. However, no studies have assessed the molecular genetics, e.g. transcriptional changes, associated with infection-induced physiological changes in resistant or susceptible trees. We constructed seven subtractive suppression hybridization (SSH) cDNA libraries using time-course sampling of trees inoculated with pine wood nematode at 1, 3, or 7 days post-inoculation (dpi) in susceptible trees and at 1, 3, 7, or 14 dpi in resistant trees. A total of 3,299 sequences was obtained from these cDNA libraries, including from 138 to 315 non-redundant sequences in susceptible SSH libraries and from 351 to 435 in resistant SSH libraries. Using Gene Ontology hierarchy, those non-redundant sequences were classified into 15 subcategories of the biological process Gene Ontology category and 17 subcategories of the molecular function category. The transcriptional components revealed by the Gene Ontology classification clearly differed between resistant and susceptible libraries. Some transcripts were discriminative: expression of antimicrobial peptide and putative pathogenesis-related genes (e.g., PR-1b, 2, 3, 4, 5, 6) was much higher in susceptible trees than in resistant trees at every time point, whereas expression of PR-9, PR-10, and cell wall-related genes (e.g., for hydroxyproline-rich glycoprotein precursor and extensin) was higher in resistant trees than in susceptible trees at 7 and 14 dpi. Following inoculation with pine wood nematode, there were marked differences between resistant and susceptible trees in transcript diversity and the timing and level of transcripts expressed in common; in particular, expression of stress response and defense genes differed. This study provided new insight into the differences in the physiological changes between resistant and susceptible trees that have been observed in anatomical and biochemical studies.

Evidence of accelerated evolution and ectodermal-specific expression of presumptive BDS toxin cDNAs from Anemonia viridis.

PubMed

Nicosia, Aldo; Maggio, Teresa; Mazzola, Salvatore; Cuttitta, Angela

2013-10-30

Anemonia viridis is a widespread and extensively studied Mediterranean species of sea anemone from which a large number of polypeptide toxins, such as blood depressing substances (BDS) peptides, have been isolated. The first members of this class, BDS-1 and BDS-2, are polypeptides belonging to the β-defensin fold family and were initially described for their antihypertensive and antiviral activities. BDS-1 and BDS-2 are 43 amino acid peptides characterised by three disulfide bonds that act as neurotoxins affecting Kv3.1, Kv3.2 and Kv3.4 channel gating kinetics. In addition, BDS-1 inactivates the Nav1.7 and Nav1.3 channels. The development of a large dataset of A. viridis expressed sequence tags (ESTs) and the identification of 13 putative BDS-like cDNA sequences has attracted interest, especially as scientific and diagnostic tools. A comparison of BDS cDNA sequences showed that the untranslated regions are more conserved than the protein-coding regions. Moreover, the KA/KS ratios calculated for all pairwise comparisons showed values greater than 1, suggesting mechanisms of accelerated evolution. The structures of the BDS homologs were predicted by molecular modelling. All toxins possess similar 3D structures that consist of a triple-stranded antiparallel β-sheet and an additional small antiparallel β-sheet located downstream of the cleavage/maturation site; however, the orientation of the triple-stranded β-sheet appears to differ among the toxins. To characterise the spatial expression profile of the putative BDS cDNA sequences, tissue-specific cDNA libraries, enriched for BDS transcripts, were constructed. In addition, the proper amplification of ectodermal or endodermal markers ensured the tissue specificity of each library. Sequencing randomly selected clones from each library revealed ectodermal-specific expression of ten BDS transcripts, while transcripts of BDS-8, BDS-13, BDS-14 and BDS-15 failed to be retrieved, likely due to under-representation in our cDNA libraries. The calculation of the relative abundance of BDS transcripts in the cDNA libraries revealed that BDS-1, BDS-3, BDS-4, BDS-5 and BDS-6 are the most represented transcripts.

A new helper phage for improved monovalent display of Fab molecules.

PubMed

Beaber, John W; Tam, Eric M; Lao, Llewelyn S; Rondon, Isaac J

2012-02-28

Phage display technology is a powerful tool for the identification of novel antibodies for drug discovery. Phage display libraries have been constructed with massive diversity, but their use may be hindered by limited antibody display levels when rescued with the M13KO7 helper phage. Variants of M13KO7 have been constructed previously that increase the levels of display of rescued phage, but all produce phage that display multiple copies of the antibody fragment on their surface and have reduced titer and infectivity. In this study, we describe a new helper phage, XP5, which increased the display level of Fab molecules more than two-fold compared to phage rescued with M13KO7. XP5 uses a combination of ribosome binding site spacing alterations and rare codon clusters to reduce the expression of pIII from the helper phage. This reduction in pIII expression leads to an increase in the incorporation of pIII-Fab fusions during phage rescue. The rescued phage displayed a single copy of the Fab molecule, preventing any avidity effects during the selection process. This also suggests that the percentage of the population of phage displaying a Fab molecule is increased when rescued with XP5. Additionally, the phage titers and infectivity are comparable to libraries rescued with M13KO7. After two rounds of panning we observed a nearly 5-fold increase in the number of antigen binding Fab molecules compared to panning conducted with the same library rescued with M13KO7. The nature of the mutations in XP5 makes it a universal substitute for M13KO7 in pIII-based phage display, compatible with most phagemids and bacterial strains. Copyright © 2011 Elsevier B.V. All rights reserved.

From the Cover: A polymer library approach to suicide gene therapy for cancer

NASA Astrophysics Data System (ADS)

Anderson, Daniel G.; Peng, Weidan; Akinc, Akin; Hossain, Naushad; Kohn, Anat; Padera, Robert; Langer, Robert; Sawicki, Janet A.

2004-11-01

Optimal gene therapy for cancer must (i) deliver DNA to tumor cells with high efficiency, (ii) induce minimal toxicity, and (iii) avoid gene expression in healthy tissues. To this end, we generated a library of >500 degradable, poly(-amino esters) for potential use as nonviral DNA vectors. Using high-throughput methods, we screened this library in vitro for transfection efficiency and cytotoxicity. We tested the best performing polymer, C32, in mice for toxicity and DNA delivery after intratumor and i.m. injection. C32 delivered DNA intratumorally 4-fold better than one of the best commercially available reagents, jetPEI (polyethyleneimine), and 26-fold better than naked DNA. Conversely, the highest transfection levels after i.m. administration were achieved with naked DNA, followed by polyethyleneimine; transfection was rarely observed with C32. Additionally, polyethyleneimine induced significant local toxicity after i.m. injection, whereas C32 demonstrated no toxicity. Finally, we used C32 to deliver a DNA construct encoding the A chain of diphtheria toxin (DT-A) to xenografts derived from LNCaP human prostate cancer cells. This construct regulates toxin expression both at the transcriptional level by the use of a chimeric-modified enhancer/promoter sequence of the human prostate-specific antigen gene and by DNA recombination mediated by Flp recombinase. C32 delivery of the A chain of diphtheria toxin DNA to LNCaP xenografts suppressed tumor growth and even caused 40% of tumors to regress in size. Because C32 transfects tumors locally at high levels, transfects healthy muscle poorly, and displays no toxicity, it may provide a vehicle for the local treatment of cancer. prostate | cationic polymers

Identification of differentially expressed genes in the zebrafish hypothalamus - pituitary axis

PubMed Central

Toro, Sabrina; Wegner, Jeremy; Muller, Marc; Westerfield, Monte; Varga, Zoltan M.

2009-01-01

The vertebrate hypothalamic-pituitary axis (HP) is the main link between the central nervous system and endocrine system. Although several signal pathways and regulatory genes have been implicated in adenohypophysis ontogenesis, little is known about hypothalamic and neurohypophysial development or when the HP matures and becomes functional. To identify markers of the HP, we constructed subtractive cDNA libraries between adult zebrafish hypothalamus and pituitary. We identified previously published genes and ESTs and novel zebrafish genes, some of which were predicted by genomic database analysis. We also analyzed expression patterns of these genes and found that several are expressed in the embryonic and larval hypothalamus, neurohypophysis, and/or adenohypophysis. Expression at these stages makes these genes useful markers to study HP maturation and function. PMID:19166982

Estimating P-coverage of biosynthetic pathways in DNA libraries and screening by genetic selection: biotin biosynthesis in the marine microorganism Chromohalobacter.

PubMed

Kim, Eun Jin; Angell, Scott; Janes, Jeff; Watanabe, Coran M H

2008-06-01

Traditional approaches to natural product discovery involve cell-based screening of natural product extracts followed by compound isolation and characterization. Their importance notwithstanding, continued mining leads to depletion of natural resources and the reisolation of previously identified metabolites. Metagenomic strategies aimed at localizing the biosynthetic cluster genes and expressing them in surrogate hosts offers one possible alternative. A fundamental question that naturally arises when pursuing such a strategy is, how large must the genomic library be to effectively represent the genome of an organism(s) and the biosynthetic gene clusters they harbor? Such an issue is certainly augmented in the absence of expensive robotics to expedite colony picking and/or screening of clones. We have developed an algorism, named BPC (biosynthetic pathway coverage), supported by molecular simulations to deduce the number of BAC clones required to achieve proper coverage of the genome and their respective biosynthetic pathways. The strategy has been applied to the construction of a large-insert BAC library from a marine microorganism, Hon6 (isolated from Honokohau, Maui) thought to represent a new species. The genomic library is constructed with a BAC yeast shuttle vector pClasper lacZ paving the way for the culturing of libraries in both prokaryotic and eukaryotic hosts. Flow cytometric methods are utilized to estimate the genome size of the organism and BPC implemented to assess P-coverage or percent coverage. A genetic selection strategy is illustrated, applications of which could expedite screening efforts in the identification and localization of biosynthetic pathways from marine microbial consortia, offering a powerful complement to genome sequencing and degenerate probe strategies. Implementing this approach, we report on the biotin biosynthetic pathway from the marine microorganism Hon6.

LSCA (Library Services and Construction Act, Title I) Special Project Reports, Fiscal Year 1976.

ERIC Educational Resources Information Center

Massachusetts State Board of Library Commissioners, Boston.

This collection of reports provides the objectives, background information, project descriptions, and evaluations for 16 public library programs funded through the Library Services and Construction Act in Massachusetts during FY 1976. The projects reflect the efforts being made by librarians to provide services to segments of their population who…

Method for construction of normalized cDNA libraries

DOEpatents

Soares, Marcelo B.; Efstratiadis, Argiris

1996-01-01

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.

Method for construction of normalized cDNA libraries

DOEpatents

Soares, M.B.; Efstratiadis, A.

1996-01-09

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form. The method comprises: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3` noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.

Construction of human antibody gene libraries and selection of antibodies by phage display.

PubMed

Frenzel, André; Kügler, Jonas; Wilke, Sonja; Schirrmann, Thomas; Hust, Michael

2014-01-01

Antibody phage display is the most commonly used in vitro selection technology and has yielded thousands of useful antibodies for research, diagnostics, and therapy.The prerequisite for successful generation and development of human recombinant antibodies using phage display is the construction of a high-quality antibody gene library. Here, we describe the methods for the construction of human immune and naive scFv gene libraries.The success also depends on the panning strategy for the selection of binders from these libraries. In this article, we describe a panning strategy that is high-throughput compatible and allows parallel selection in microtiter plates.

An insight into the sialome of Glossina morsitans morsitans

PubMed Central

2010-01-01

Background Blood feeding evolved independently in worms, arthropods and mammals. Among the adaptations to this peculiar diet, these animals developed an armament of salivary molecules that disarm their host's anti-bleeding defenses (hemostasis), inflammatory and immune reactions. Recent sialotranscriptome analyses (from the Greek sialo = saliva) of blood feeding insects and ticks have revealed that the saliva contains hundreds of polypeptides, many unique to their genus or family. Adult tsetse flies feed exclusively on vertebrate blood and are important vectors of human and animal diseases. Thus far, only limited information exists regarding the Glossina sialome, or any other fly belonging to the Hippoboscidae. Results As part of the effort to sequence the genome of Glossina morsitans morsitans, several organ specific, high quality normalized cDNA libraries have been constructed, from which over 20,000 ESTs from an adult salivary gland library were sequenced. These ESTs have been assembled using previously described ESTs from the fat body and midgut libraries of the same fly, thus totaling 62,251 ESTs, which have been assembled into 16,743 clusters (8,506 of which had one or more EST from the salivary gland library). Coding sequences were obtained for 2,509 novel proteins, 1,792 of which had at least one EST expressed in the salivary glands. Despite library normalization, 59 transcripts were overrepresented in the salivary library indicating high levels of expression. This work presents a detailed analysis of the salivary protein families identified. Protein expression was confirmed by 2D gel electrophoresis, enzymatic digestion and mass spectrometry. Concurrently, an initial attempt to determine the immunogenic properties of selected salivary proteins was undertaken. Conclusions The sialome of G. m. morsitans contains over 250 proteins that are possibly associated with blood feeding. This set includes alleles of previously described gene products, reveals new evidence that several salivary proteins are multigenic and identifies at least seven new polypeptide families unique to Glossina. Most of these proteins have no known function and thus, provide a discovery platform for the identification of novel pharmacologically active compounds, innovative vector-based vaccine targets, and immunological markers of vector exposure. PMID:20353571

Comparison of the efficiency of antibody selection from semi-synthetic scFv and non-immune Fab phage display libraries against protein targets for rapid development of diagnostic immunoassays.

PubMed

Chan, Conrad E Z; Chan, Annie H Y; Lim, Angeline P C; Hanson, Brendon J

2011-10-28

Rapid development of diagnostic immunoassays against novel emerging or genetically modified pathogens in an emergency situation is dependent on the timely isolation of specific antibodies. Non-immune antibody phage display libraries are an efficient in vitro method for selecting monoclonal antibodies and hence ideal in these circumstances. Such libraries can be constructed from a variety of sources e.g. B cell cDNA or synthetically generated, and use a variety of antibody formats, typically scFv or Fab. However, antibody source and format can impact on the quality of antibodies generated and hence the effectiveness of this methodology for the timely production of antibodies. We have carried out a comparative screening of two antibody libraries, a semi-synthetic scFv library and a human-derived Fab library against the protective antigen toxin component of Bacillus anthracis and the epsilon toxin of Clostridium botulinum. We have shown that while the synthetic library produced a diverse collection of specific scFv-phage, these contained a high frequency of unnatural amber stops and glycosylation sites which limited their conversion to IgG, and also a high number which lost specificity when expressed as IgG. In contrast, these limitations were overcome by the use of a natural human library. Antibodies from both libraries could be used to develop sandwich ELISA assays with similar sensitivity. However, the ease and speed with which full-length IgG could be generated from the human-derived Fab library makes screening this type of library the preferable method for rapid antibody generation for diagnostic assay development. Copyright © 2011 Elsevier B.V. All rights reserved.

Long-range transcriptional interference in E. coli used to construct a dual positive selection system for genetic switches

PubMed Central

Hoffmann, Stefan A.; Kruse, Sabrina M.; Arndt, Katja M.

2016-01-01

Abstract We have investigated transcriptional interference between convergent genes in E. coli and demonstrate substantial interference for inter-promoter distances of as far as 3 kb. Interference can be elicited by both strong σ70 dependent and T7 promoters. In the presented design, a strong promoter driving gene expression of a ‘forward’ gene interferes with the expression of a ‘reverse’ gene by a weak promoter. This arrangement allows inversely correlated gene expression without requiring further regulatory components. Thus, modulation of the activity of the strong promoter alters expression of both the forward and the reverse gene. We used this design to develop a dual selection system for conditional operator site binding, allowing positive selection both for binding and for non-binding to DNA. This study demonstrates the utility of this novel system using the Lac repressor as a model protein for conditional DNA binding, and spectinomycin and chloramphenicol resistance genes as positive selection markers in liquid culture. Randomized LacI libraries were created and subjected to subsequent dual selection, but mispairing IPTG and selection cues in respect to the wild-type LacI response, allowing the isolation of a LacI variant with a reversed IPTG response within three rounds of library generation and dual selection. PMID:26932362

Differential expression of the lethal gene Luteus-Pa in cacao of the Parinari series.

PubMed

Rehem, B C; Almeida, A-A F; Figueiredo, G S F; Gesteira, A S; Santos, S C; Corrêa, R X; Yamada, M M; Valle, R R

2016-02-22

The recessive lethal character Luteus-Pa is found in cacao (Theobroma cacao) genotypes of the Parinari series (Pa) and is characterized by expression of leaf chlorosis and seedling death. Several genotypes of the Pa series are bearers of the gene responsible for the expression of the Luteus-Pa character, which can be used as a tool for determining relationships between genotypes of this group. To evaluate this phenomenon, we analyzed the differential expression of genes between mutant seedlings and wild-type hybrid Pa 30 x 169 seedlings, with the aim of elucidating the possible lethal mechanisms of the homozygous recessive character Luteus-Pa. Plant material was harvested from leaves of wild and mutant seedlings at different periods to construct a subtractive library and perform quantitative analysis using real-time PCR. The 649 sequences obtained from the subtractive library had an average length of 500 bp, forming 409 contigs. The probable proteins encoded were grouped into 10 functional categories. Data from ESTs identified genes associated with Rubisco, peroxidases, and other proteins and enzymes related to carbon assimilation, respiration, and photosystem 2. Mutant seedlings were characterized by synthesizing defective PsbO and PsbA proteins, which were overexpressed from 15 to 20 days after seedling emergence.

Identification of Useful Nanobodies by Phage Display of Immune Single Domain Libraries Derived from Camelid Heavy Chain Antibodies.

PubMed

Romao, Ema; Morales-Yanez, Francisco; Hu, Yaozhong; Crauwels, Maxine; De Pauw, Pieter; Hassanzadeh, Gholamreza Ghassanzadeh; Devoogdt, Nick; Ackaert, Chloe; Vincke, Cecile; Muyldermans, Serge

2016-01-01

The discovery of functional heavy chain-only antibodies devoid of light chains in sera of camelids and sharks in the early nineties provided access to the generation of minimal-sized, single-domain, in vivo affinity-matured, recombinant antigenbinding fragments, also known as Nanobodies. Recombinant DNA technology and adaptation of phage display vectors form the basis to construct large naïve, synthetic or medium sized immune libraries from where multiple Nanobodies have been retrieved. Alternative selection methods (i.e. bacterial display, bacterial two-hybrid, Cis-display and ribosome display) have also been developed to identify Nanobodies. The antigen affinity, stability, expression yields and structural details of the Nanobodies have been determined by standard technology. Nanobodies were subsequently engineered for higher stability and affinity, to have a sequence closer to that of human immunoglobulin domains, or to add designed effector functions. Antigen specific Nanobodies recognizing with high affinity their cognate antigen were retrieved from various libraries. High expression yields are obtained from microorganisms, even when expressed in the cytoplasm. The purified Nanobodies are shown to possess beneficial biochemical and biophysical properties. The crystal structure of Nanobody::antigen complexes reveal the preference of Nanobodies for cavities on the antigen surface. Thanks to the properties described above, Nanobodies became a highly valued and versatile tool for biomolecular research. Moreover, numerous diagnostic and therapeutic Nanobody-based applications have been developed in the past decade. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Phylogenetic and gene expression analysis of cyanobacteria and diatoms in the twilight waters of the temperate northeast Pacific Ocean.

PubMed

Gao, Weimin; Shi, Xu; Wu, Jieying; Jin, Yuguang; Zhang, Weiwen; Meldrum, Deirdre R

2011-11-01

In this study, to explore the microbial community structure and its functionality in the deep-sea environments, we initially performed a 16S ribosomal RNA (rRNA)-based community structure analyses for microbial communities in the sea water collected from sites of 765-790 m in depth in the Pacific Ocean. Interestingly, in the clone library we detected the presence of both photoautotrophic bacteria such as cyanobacteria and photoheterotrophic bacteria, such as Chloroflexus sp. To further explore the existence and diversity of possible light-utilizing microorganisms, we then constructed and analyzed a 23S rRNA plastid gene cloning library. The results showed that the majority of this cloning library was occupied by oxygenic photoautotrophic organisms, such as diatoms Thalassiosira spp. and cyanobacterium Synechococcus sp. In addition, the diversity of these oxygenic photoautotrophic organisms was very limited. Moreover, both reverse-transcription PCR and quantitative reverse-transcription PCR approaches had been employed to detect expression of the genes involved in protein synthesis and photosynthesis of photoautotrophic organisms, and the positive results were obtained. The possible mechanisms underlying the existence of very limited diversity of photosynthetic organisms at this depth of ocean, as well as the positive detection of rRNA and mRNA of diatom and cyanobacteria, were discussed.

EcoFlex: A Multifunctional MoClo Kit for E. coli Synthetic Biology.

PubMed

Moore, Simon J; Lai, Hung-En; Kelwick, Richard J R; Chee, Soo Mei; Bell, David J; Polizzi, Karen Marie; Freemont, Paul S

2016-10-21

Golden Gate cloning is a prominent DNA assembly tool in synthetic biology for the assembly of plasmid constructs often used in combinatorial pathway optimization, with a number of assembly kits developed specifically for yeast and plant-based expression. However, its use for synthetic biology in commonly used bacterial systems such as Escherichia coli has surprisingly been overlooked. Here, we introduce EcoFlex a simplified modular package of DNA parts for a variety of applications in E. coli, cell-free protein synthesis, protein purification and hierarchical assembly of transcription units based on the MoClo assembly standard. The kit features a library of constitutive promoters, T7 expression, RBS strength variants, synthetic terminators, protein purification tags and fluorescence proteins. We validate EcoFlex by assembling a 68-part containing (20 genes) plasmid (31 kb), characterize in vivo and in vitro library parts, and perform combinatorial pathway assembly, using pooled libraries of either fluorescent proteins or the biosynthetic genes for the antimicrobial pigment violacein as a proof-of-concept. To minimize pathway screening, we also introduce a secondary module design site to simplify MoClo pathway optimization. In summary, EcoFlex provides a standardized and multifunctional kit for a variety of applications in E. coli synthetic biology.

Selection and expression of recombinant single domain antibodies from a hyper-immunized library against the hapten azoxystrobin.

PubMed

Makvandi-Nejad, Shokouh; Fjällman, Ted; Arbabi-Ghahroudi, Mehdi; MacKenzie, C Roger; Hall, J Christopher

2011-10-28

Three V(H)Hs against the model hapten, azoxystrobin (MW 403), were isolated from a hyper-immunized phage-displayed V(H)H library. This library was constructed by isolating the V(H)H-coding genes from the lymphocytes collected from a Llama glama that was immunized with azoxystrobin conjugated to bovine serum albumin (BSA). Six rounds of panning were performed against azoxystrobin conjugated to either ovalbumin (OVA) or rabbit serum albumin (RSA) to enrich clones containing V(H)Hs specific to the hapten. After screening 95 clones, three V(H)Hs (A27, A72, and A85) with different amino acid sequences were identified, expressed in soluble format in Escherichia coli HB2151, and purified using nickel-immobilized metal affinity chromatography. Competitive inhibition enzyme-linked immunosorbent assay (CI-ELISA) showed that A27 and A85 were specific to azoxystrobin while A72 was not. The IC(50) values of A27 and A85 V(H)Hs were 7.2 and 2.0μM, respectively. To our knowledge A85 is one of the highest affinity V(H)Hs that has yet been isolated against a hydrophobic hapten such as azoxystrobin. Copyright © 2011 Elsevier B.V. All rights reserved.

Transcriptomic analysis of Ruditapes philippinarum hemocytes reveals cytoskeleton disruption after in vitro Vibrio tapetis challenge.

PubMed

Brulle, Franck; Jeffroy, Fanny; Madec, Stéphanie; Nicolas, Jean-Louis; Paillard, Christine

2012-10-01

The Manila clam, Ruditapes philippinarum, is an economically-important, commercial shellfish; harvests are diminished in some European waters by a pathogenic bacterium, Vibrio tapetis, that causes Brown Ring disease. To identify molecular characteristics associated with susceptibility or resistance to Brown Ring disease, Suppression Subtractive Hybridization (SSH) analyzes were performed to construct cDNA libraries enriched in up- or down-regulated transcripts from clam immune cells, hemocytes, after a 3-h in vitro challenge with cultured V. tapetis. Nine hundred and ninety eight sequences from the two libraries were sequenced, and an in silico analysis identified 235 unique genes. BLAST and "Gene ontology" classification analyzes revealed that 60.4% of the Expressed Sequence Tags (ESTs) have high similarities with genes involved in various physiological functions, such as immunity, apoptosis and cytoskeleton organization; whereas, 39.6% remain unidentified. From the 235 unique genes, we selected 22 candidates based upon physiological function and redundancy in the libraries. Then, Real-Time PCR analysis identified 3 genes related to cytoskeleton organization showing significant variation in expression attributable to V. tapetis exposure. Disruption in regulation of these genes is consistent with the etiologic agent of Brown Ring disease in Manila clams. Copyright © 2012 Elsevier Ltd. All rights reserved.

Coral life history and symbiosis: Functional genomic resources for two reef building Caribbean corals, Acropora palmata and Montastraea faveolata

PubMed Central

Schwarz, Jodi A; Brokstein, Peter B; Voolstra, Christian; Terry, Astrid Y; Miller, David J; Szmant, Alina M; Coffroth, Mary Alice; Medina, Mónica

2008-01-01

Background Scleractinian corals are the foundation of reef ecosystems in tropical marine environments. Their great success is due to interactions with endosymbiotic dinoflagellates (Symbiodinium spp.), with which they are obligately symbiotic. To develop a foundation for studying coral biology and coral symbiosis, we have constructed a set of cDNA libraries and generated and annotated ESTs from two species of corals, Acropora palmata and Montastraea faveolata. Results We generated 14,588 (Ap) and 3,854 (Mf) high quality ESTs from five life history/symbiosis stages (spawned eggs, early-stage planula larvae, late-stage planula larvae either infected with symbionts or uninfected, and adult coral). The ESTs assembled into a set of primarily stage-specific clusters, producing 4,980 (Ap), and 1,732 (Mf) unigenes. The egg stage library, relative to the other developmental stages, was enriched in genes functioning in cell division and proliferation, transcription, signal transduction, and regulation of protein function. Fifteen unigenes were identified as candidate symbiosis-related genes as they were expressed in all libraries constructed from the symbiotic stages and were absent from all of the non symbiotic stages. These include several DNA interacting proteins, and one highly expressed unigene (containing 17 cDNAs) with no significant protein-coding region. A significant number of unigenes (25) encode potential pattern recognition receptors (lectins, scavenger receptors, and others), as well as genes that may function in signaling pathways involved in innate immune responses (toll-like signaling, NFkB p105, and MAP kinases). Comparison between the A. palmata and an A. millepora EST dataset identified ferritin as a highly expressed gene in both datasets that appears to be undergoing adaptive evolution. Five unigenes appear to be restricted to the Scleractinia, as they had no homology to any sequences in the nr databases nor to the non-scleractinian cnidarians Nematostella vectensis and Hydra magnipapillata. Conclusion Partial sequencing of 5 cDNA libraries each for A. palmata and M. faveolata has produced a rich set of candidate genes (4,980 genes from A. palmata, and 1,732 genes from M. faveolata) that we can use as a starting point for examining the life history and symbiosis of these two species, as well as to further expand the dataset of cnidarian genes for comparative genomics and evolutionary studies. PMID:18298846

Coral Life History and Symbiosis: functional genomic resources for two reef building Caribbean corals, Acropora palmata and Montastraea faveolata

DOE PAGES

Schwarz, Jodi A.; Brokstein, Peter B.; Voolstra, Christian R.; ...

2008-02-25

Scleractinian corals are the foundation of reef ecosystems in tropical marine environments. Their great success is due to interactions with endosymbiotic dinoflagellates (Symbiodinium spp.), with which they are obligately symbiotic. To develop a foundation for studying coral biology and coral symbiosis, we have constructed a set of cDNA libraries and generated and annotated ESTs from two species of corals, Acropora palmata and Montastraea faveolata. Here we generated 14,588 (Ap) and 3,854 (Mf) high quality ESTs from five life history/symbiosis stages (spawned eggs, early-stage planula larvae, late-stage planula larvae either infected with symbionts or uninfected, and adult coral). The ESTs assembledmore » into a set of primarily stage-specific clusters, producing 4,980 (Ap), and 1,732 (Mf) unigenes. The egg stage library, relative to the other developmental stages, was enriched in genes functioning in cell division and proliferation, transcription, signal transduction, and regulation of protein function. Fifteen unigenes were identified as candidate symbiosis-related genes as they were expressed in all libraries constructed from the symbiotic stages and were absent from all of the non symbiotic stages. These include several DNA interacting proteins, and one highly expressed unigene (containing 17 cDNAs) with no significant protein-coding region. A significant number of unigenes (25) encode potential pattern recognition receptors (lectins, scavenger receptors, and others), as well as genes that may function in signaling pathways involved in innate immune responses (toll-like signaling, NFkB p105, and MAP kinases). Comparison between the A. palmata and an A. millepora EST dataset identified ferritin as a highly expressed gene in both datasets that appears to be undergoing adaptive evolution. Five unigenes appear to be restricted to the Scleractinia, as they had no homology to any sequences in the nr databases nor to the non-scleractinian cnidarians Nematostella vectensis and Hydra magnipapillata. In conclusion, partial sequencing of 5 cDNA libraries each for A. palmata and M. faveolata has produced a rich set of candidate genes (4,980 genes from A. palmata, and 1,732 genes from M. faveolata) that we can use as a starting point for examining the life history and symbiosis of these two species, as well as to further expand the dataset of cnidarian genes for comparative genomics and evolutionary studies.« less

Coral Life History and Symbiosis: functional genomic resources for two reef building Caribbean corals, Acropora palmata and Montastraea faveolata

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwarz, Jodi A.; Brokstein, Peter B.; Voolstra, Christian R.

Scleractinian corals are the foundation of reef ecosystems in tropical marine environments. Their great success is due to interactions with endosymbiotic dinoflagellates (Symbiodinium spp.), with which they are obligately symbiotic. To develop a foundation for studying coral biology and coral symbiosis, we have constructed a set of cDNA libraries and generated and annotated ESTs from two species of corals, Acropora palmata and Montastraea faveolata. Here we generated 14,588 (Ap) and 3,854 (Mf) high quality ESTs from five life history/symbiosis stages (spawned eggs, early-stage planula larvae, late-stage planula larvae either infected with symbionts or uninfected, and adult coral). The ESTs assembledmore » into a set of primarily stage-specific clusters, producing 4,980 (Ap), and 1,732 (Mf) unigenes. The egg stage library, relative to the other developmental stages, was enriched in genes functioning in cell division and proliferation, transcription, signal transduction, and regulation of protein function. Fifteen unigenes were identified as candidate symbiosis-related genes as they were expressed in all libraries constructed from the symbiotic stages and were absent from all of the non symbiotic stages. These include several DNA interacting proteins, and one highly expressed unigene (containing 17 cDNAs) with no significant protein-coding region. A significant number of unigenes (25) encode potential pattern recognition receptors (lectins, scavenger receptors, and others), as well as genes that may function in signaling pathways involved in innate immune responses (toll-like signaling, NFkB p105, and MAP kinases). Comparison between the A. palmata and an A. millepora EST dataset identified ferritin as a highly expressed gene in both datasets that appears to be undergoing adaptive evolution. Five unigenes appear to be restricted to the Scleractinia, as they had no homology to any sequences in the nr databases nor to the non-scleractinian cnidarians Nematostella vectensis and Hydra magnipapillata. In conclusion, partial sequencing of 5 cDNA libraries each for A. palmata and M. faveolata has produced a rich set of candidate genes (4,980 genes from A. palmata, and 1,732 genes from M. faveolata) that we can use as a starting point for examining the life history and symbiosis of these two species, as well as to further expand the dataset of cnidarian genes for comparative genomics and evolutionary studies.« less

Dual genetic selection of synthetic riboswitches in Escherichia coli.

PubMed

Nomura, Yoko; Yokobayashi, Yohei

2014-01-01

This chapter describes a genetic selection strategy to engineer synthetic riboswitches that can chemically regulate gene expression in Escherichia coli. Riboswitch libraries are constructed by randomizing the nucleotides that potentially comprise an expression platform and fused to the hybrid selection/screening marker tetA-gfpuv. Iterative ON and OFF selections are performed under appropriate conditions that favor the survival or the growth of the cells harboring the desired riboswitches. After the selection, rapid screening of individual riboswitch clones is performed by measuring GFPuv fluorescence without subcloning. This optimized dual genetic selection strategy can be used to rapidly develop synthetic riboswitches without detailed computational design or structural knowledge.

Retroviral expression screening of oncogenes in natural killer cell leukemia.

PubMed

Choi, Young Lim; Moriuchi, Ryozo; Osawa, Mitsujiro; Iwama, Atsushi; Makishima, Hideki; Wada, Tomoaki; Kisanuki, Hiroyuki; Kaneda, Ruri; Ota, Jun; Koinuma, Koji; Ishikawa, Madoka; Takada, Shuji; Yamashita, Yoshihiro; Oshimi, Kazuo; Mano, Hiroyuki

2005-08-01

Aggressive natural killer cell leukemia (ANKL) is an intractable malignancy that is characterized by the outgrowth of NK cells. To identify transforming genes in ANKL, we constructed a retroviral cDNA expression library from an ANKL cell line KHYG-1. Infection of 3T3 cells with recombinant retroviruses yielded 33 transformed foci. Nucleotide sequencing of the DNA inserts recovered from these foci revealed that 31 of them encoded KRAS2 with a glycine-to-alanine mutation at codon 12. Mutation-specific PCR analysis indicated that the KRAS mutation was present only in KHYG-1 cells, not in another ANKL cell line or in clinical specimens (n=8).

One library to make them all: streamlining the creation of yeast libraries via a SWAp-Tag strategy.

PubMed

Yofe, Ido; Weill, Uri; Meurer, Matthias; Chuartzman, Silvia; Zalckvar, Einat; Goldman, Omer; Ben-Dor, Shifra; Schütze, Conny; Wiedemann, Nils; Knop, Michael; Khmelinskii, Anton; Schuldiner, Maya

2016-04-01

The yeast Saccharomyces cerevisiae is ideal for systematic studies relying on collections of modified strains (libraries). Despite the significance of yeast libraries and the immense variety of available tags and regulatory elements, only a few such libraries exist, as their construction is extremely expensive and laborious. To overcome these limitations, we developed a SWAp-Tag (SWAT) method that enables one parental library to be modified easily and efficiently to give rise to an endless variety of libraries of choice. To showcase the versatility of the SWAT approach, we constructed and investigated a library of ∼1,800 strains carrying SWAT-GFP modules at the amino termini of endomembrane proteins and then used it to create two new libraries (mCherry and seamless GFP). Our work demonstrates how the SWAT method allows fast and effortless creation of yeast libraries, opening the door to new ways of systematically studying cell biology.

Building a New Library or Renovating an Old: Some Things To Consider.

ERIC Educational Resources Information Center

McCabe, Gerard B.

This article provides suggestions for librarians who are planning for the construction of new library buildings or the renovation or conversion of older buildings. The recommendations are based on practical experience gained by a Director of University Libraries in the planning and construction of Tompkins-McCaw and James Branch Cabell Libraries…

Libraries 2000: Allocation Plan for FY1995 LSCA Funds, Library Service and Construction Act. An Annual Outline and Description of Projects in Idaho Eligible under LSCA Titles I, II, and III.

ERIC Educational Resources Information Center

Idaho State Library, Boise.

The Idaho allocation plan for funds from the Library Service and Construction Act continues the emphasis on priorities listed in fiscal year 1994 and those that were described in the statewide plan for the years 1994 through 1998. These priorities are: (1) advocate for the creation of library districts with adequate tax support to serve the…

Libraries 2000: Allocation Plan for FY1997 LSCA Funds, Library Services and Construction Act. An Annual Outline and Description of Projects in Idaho Eligible under LSCA Titles I, II, and III.

ERIC Educational Resources Information Center

Idaho State Library, Boise.

The Idaho allocation plan for funds from the Library Service and Construction Act (LSCA) continues the emphasis on priorities described in the statewide plan for years 1994-1998. These priorities are: (1) advocate for the creation of library districts with adequate tax support to serve the state's entire population; (2) strengthen cooperation and…

From genes to protein mechanics on a chip.

PubMed

Otten, Marcus; Ott, Wolfgang; Jobst, Markus A; Milles, Lukas F; Verdorfer, Tobias; Pippig, Diana A; Nash, Michael A; Gaub, Hermann E

2014-11-01

Single-molecule force spectroscopy enables mechanical testing of individual proteins, but low experimental throughput limits the ability to screen constructs in parallel. We describe a microfluidic platform for on-chip expression, covalent surface attachment and measurement of single-molecule protein mechanical properties. A dockerin tag on each protein molecule allowed us to perform thousands of pulling cycles using a single cohesin-modified cantilever. The ability to synthesize and mechanically probe protein libraries enables high-throughput mechanical phenotyping.

Chemical Library Screening for Potential Therapeutics Using Novel Cell Based Models of ALS

DTIC Science & Technology

2017-06-01

Major Task 1, Subtask 1. Our first major activity in year 1 was the design and engineering of a custom inducible plasmid for expressing fluorescently...back to that construct. Other achievements during this first major activity derived from investigating why Broccoli RNA aptamer did not fold...These are outlined below in the CHANGES/PROBLEMS section. Major Task 1, Subtask 2. Our second major activity in year 1 was to generate human neural

[Screening and identification of anoikis-resistant gene UBCH7 in esophageal cancer cells].

PubMed

Yang, Yang; Wang, Bo-Shi; Wang, Xiao-Min; Zhang, Yu; Wang, Ming-Rong; Jia, Xue-Mei

2012-02-01

Anoikis is a kind of programmed cell death induced by loss of extracellular matrix (ECM) adhesion, which is one of key factors for homestasis. Resistance to anoikis is required for tumor cell metastasis. We have previously shown several anoikis-resistance genes in esophageal squamous cell carcinoma (ESCC). In order to find novel anoikis-resistant genes in ESCC, we constructed retroviral cDNA library using total RNA from ESCC cell lines. NIH 3T3 cells, which are sensitive to anoikis, were infected with the library constructed. The cells were cultured in soft agar, and the clones which can survive in detached states were selected. The cDNAs inserted into the anoikis-resistant NIH3T3 clones were amplified using retroviral specific primers. Sequencing analysis showed that a cDNA fragment inserted into the anoikis-resistant clone contains full coding sequence (ORF) of human UBCH7/UBE2L3 gene. By infection with retrovirus encoding UBCH7 ORF (pMSCV-UBCH7), forced expression of UBCH7 increased the anoikis-resistance of NIH3T3 cells. More importantly, knockdown of UBCH7 expression by siRNA transfection reduced the anoikis-resistant ability of esophageal cancer MLuC1 cells. The data suggest that UBCH7/UBE2L3 gene would be involved in anoikis-resistance in ESCC.

A large scale analysis of cDNA in Arabidopsis thaliana: generation of 12,028 non-redundant expressed sequence tags from normalized and size-selected cDNA libraries.

PubMed

Asamizu, E; Nakamura, Y; Sato, S; Tabata, S

2000-06-30

For comprehensive analysis of genes expressed in the model dicotyledonous plant, Arabidopsis thaliana, expressed sequence tags (ESTs) were accumulated. Normalized and size-selected cDNA libraries were constructed from aboveground organs, flower buds, roots, green siliques and liquid-cultured seedlings, respectively, and a total of 14,026 5'-end ESTs and 39,207 3'-end ESTs were obtained. The 3'-end ESTs could be clustered into 12,028 non-redundant groups. Similarity search of the non-redundant ESTs against the public non-redundant protein database indicated that 4816 groups show similarity to genes of known function, 1864 to hypothetical genes, and the remaining 5348 are novel sequences. Gene coverage by the non-redundant ESTs was analyzed using the annotated genomic sequences of approximately 10 Mb on chromosomes 3 and 5. A total of 923 regions were hit by at least one EST, among which only 499 regions were hit by the ESTs deposited in the public database. The result indicates that the EST source generated in this project complements the EST data in the public database and facilitates new gene discovery.

Characterization of gonadal transcriptomes from the turbot (Scophthalmus maximus).

PubMed

Hu, Yulong; Huang, Meng; Wang, Weiji; Guan, Jiantao; Kong, Jie

2016-01-01

The mechanisms underlying sexual reproduction and sex ratio determination remains unclear in turbot, a flatfish of great commercial value. And there is limited information in the turbot database regarding genes related to the reproductive system. Here, we conducted high-throughput transcriptome profiling of turbot gonad tissues to better understand their reproductive functions and to supply essential gene sequence information for marker-assisted selection programs in the turbot industry. In this study, two gonad libraries representing sex differences in Scophthalmus maximus yielded 453 818 high-quality reads that were assembled into 24 611 contigs and 33 713 singletons by using 454 pyrosequencing, 13 936 contigs and singletons (CS) of which were annotated using BLASTx. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analyses revealed that various biological functions and processes were associated with many of the annotated CS. Expression analyses showed that 510 genes were differentially expressed in males versus females; 80% of these genes were annotated. In addition, 6484 and 6036 single nucleotide polymorphisms (SNPs) were identified in male and female libraries, respectively. This transcriptome resource will serve as the foundation for cDNA or SNP microarray construction, gene expression characterization, and sex-specific linkage mapping in turbot.

Identification of expressed genes in cDNA library of hemocytes from the RLO-challenged oyster, Crassostrea ariakensis Gould with special functional implication of three complement-related fragments (CaC1q1, CaC1q2 and CaC3).

PubMed

Xu, Ting; Xie, Jiasong; Li, Jianming; Luo, Ming; Ye, Shigen; Wu, Xinzhong

2012-06-01

A SMARTer™ cDNA library of hemocyte from Rickettsia-like organism (RLO) challenged oyster, Crassostrea ariakensis Gould was constructed. Random clones (400) were selected and single-pass sequenced, resulted in 200 unique sequences containing 96 known genes and 104 unknown genes. The 96 known genes were categorized into 11 groups based on their biological process. Furthermore, we identified and characterized three complement-related fragments (CaC1q1, CaC1q2 and CaC3). Tissue distribution analysis revealed that all of three fragments were ubiquitously expressed in all tissues studied including hemocyte, gills, mantle, digestive glands, gonads and adductor muscle, while the highest level was seen in the hemocyte. Temporal expression profile in the hemocyte monolayers reveled that the mRNA expression levels of three fragments presented huge increase after the RLO incubation at 3 h and 6 h in post-challenge, respectively. And the maximal expression levels at 3 h in post-challenge are about 256, 104 and 64 times higher than the values detected in the control of CaC1q1, CaC1q2 and CaC3, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

Transcriptional Analysis of Drought-Induced Genes in the Roots of a Tolerant Genotype of the Common Bean (Phaseolus vulgaris L.)

PubMed Central

Recchia, Gustavo Henrique; Caldas, Danielle Gregorio Gomes; Beraldo, Ana Luiza Ahern; da Silva, Márcio José; Tsai, Siu Mui

2013-01-01

In Brazil, common bean (Phaseolus vulgaris L.) productivity is severely affected by drought stress due to low technology cultivation systems. Our purpose was to identify differentially expressed genes in roots of a genotype tolerant to water deficit (BAT 477) when submitted to an interruption of irrigation during its development. A SSH library was constructed taking as “driver” the genotype Carioca 80SH (susceptible to drought). After clustering and data mining, 1572 valid reads were obtained, resulting in 1120 ESTs (expressed sequence tags). We found sequences for transcription factors, carbohydrates metabolism, proline-rich proteins, aquaporins, chaperones and ubiquitins, all of them organized according to their biological processes. Our suppressive subtractive hybridization (SSH) library was validated through RT-qPCR experiment by assessing the expression patterns of 10 selected genes in both genotypes under stressed and control conditions. Finally, the expression patterns of 31 ESTs, putatively related to drought responses, were analyzed in a time-course experiment. Our results confirmed that such genes are more expressed in the tolerant genotype during stress; however, they are not exclusive, since different levels of these transcripts were also detected in the susceptible genotype. In addition, we observed a fluctuation in gene regulation over time for both the genotypes, which seem to adopt and adapt different strategies in order to develop tolerance against this stress. PMID:23538843

Construction and characterization of normalized cDNA libraries by 454 pyrosequencing and estimation of DNA methylation levels in three distantly related termite species.

PubMed

Hayashi, Yoshinobu; Shigenobu, Shuji; Watanabe, Dai; Toga, Kouhei; Saiki, Ryota; Shimada, Keisuke; Bourguignon, Thomas; Lo, Nathan; Hojo, Masaru; Maekawa, Kiyoto; Miura, Toru

2013-01-01

In termites, division of labor among castes, categories of individuals that perform specialized tasks, increases colony-level productivity and is the key to their ecological success. Although molecular studies on caste polymorphism have been performed in termites, we are far from a comprehensive understanding of the molecular basis of this phenomenon. To facilitate future molecular studies, we aimed to construct expressed sequence tag (EST) libraries covering wide ranges of gene repertoires in three representative termite species, Hodotermopsis sjostedti, Reticulitermes speratus and Nasutitermes takasagoensis. We generated normalized cDNA libraries from whole bodies, except for guts containing microbes, of almost all castes, sexes and developmental stages and sequenced them with the 454 GS FLX titanium system. We obtained >1.2 million quality-filtered reads yielding >400 million bases for each of the three species. Isotigs, which are analogous to individual transcripts, and singletons were produced by assembling the reads and annotated using public databases. Genes related to juvenile hormone, which plays crucial roles in caste differentiation of termites, were identified from the EST libraries by BLAST search. To explore the potential for DNA methylation, which plays an important role in caste differentiation of honeybees, tBLASTn searches for DNA methyltransferases (dnmt1, dnmt2 and dnmt3) and methyl-CpG binding domain (mbd) were performed against the EST libraries. All four of these genes were found in the H. sjostedti library, while all except dnmt3 were found in R. speratus and N. takasagoensis. The ratio of the observed to the expected CpG content (CpG O/E), which is a proxy for DNA methylation level, was calculated for the coding sequences predicted from the isotigs and singletons. In all of the three species, the majority of coding sequences showed depletion of CpG O/E (less than 1), and the distributions of CpG O/E were bimodal, suggesting the presence of DNA methylation.

Construction and Characterization of Normalized cDNA Libraries by 454 Pyrosequencing and Estimation of DNA Methylation Levels in Three Distantly Related Termite Species

PubMed Central

Hayashi, Yoshinobu; Shigenobu, Shuji; Watanabe, Dai; Toga, Kouhei; Saiki, Ryota; Shimada, Keisuke; Bourguignon, Thomas; Lo, Nathan; Hojo, Masaru; Maekawa, Kiyoto; Miura, Toru

2013-01-01

In termites, division of labor among castes, categories of individuals that perform specialized tasks, increases colony-level productivity and is the key to their ecological success. Although molecular studies on caste polymorphism have been performed in termites, we are far from a comprehensive understanding of the molecular basis of this phenomenon. To facilitate future molecular studies, we aimed to construct expressed sequence tag (EST) libraries covering wide ranges of gene repertoires in three representative termite species, Hodotermopsis sjostedti , Reticulitermessperatus and Nasutitermestakasagoensis . We generated normalized cDNA libraries from whole bodies, except for guts containing microbes, of almost all castes, sexes and developmental stages and sequenced them with the 454 GS FLX titanium system. We obtained >1.2 million quality-filtered reads yielding >400 million bases for each of the three species. Isotigs, which are analogous to individual transcripts, and singletons were produced by assembling the reads and annotated using public databases. Genes related to juvenile hormone, which plays crucial roles in caste differentiation of termites, were identified from the EST libraries by BLAST search. To explore the potential for DNA methylation, which plays an important role in caste differentiation of honeybees, tBLASTn searches for DNA methyltransferases (dnmt1, dnmt2 and dnmt3) and methyl-CpG binding domain (mbd) were performed against the EST libraries. All four of these genes were found in the H . sjostedti library, while all except dnmt3 were found in R . speratus and N . takasagoensis . The ratio of the observed to the expected CpG content (CpG O/E), which is a proxy for DNA methylation level, was calculated for the coding sequences predicted from the isotigs and singletons. In all of the three species, the majority of coding sequences showed depletion of CpG O/E (less than 1), and the distributions of CpG O/E were bimodal, suggesting the presence of DNA methylation. PMID:24098800

Creating stable stem regions for loop elongation in Fcabs — Insights from combining yeast surface display, in silico loop reconstruction and molecular dynamics simulations

PubMed Central

Hasenhindl, Christoph; Lai, Balder; Delgado, Javier; Traxlmayr, Michael W.; Stadlmayr, Gerhard; Rüker, Florian; Serrano, Luis; Oostenbrink, Chris; Obinger, Christian

2014-01-01

Fcabs (Fc antigen binding) are crystallizable fragments of IgG where the C-terminal structural loops of the CH3 domain are engineered for antigen binding. For the design of libraries it is beneficial to know positions that will permit loop elongation to increase the potential interaction surface with antigen. However, the insertion of additional loop residues might impair the immunoglobulin fold. In the present work we have probed whether stabilizing mutations flanking the randomized and elongated loop region improve the quality of Fcab libraries. In detail, 13 libraries were constructed having the C-terminal part of the EF loop randomized and carrying additional residues (1, 2, 3, 5 or 10, respectively) in the absence and presence of two flanking mutations. The latter have been demonstrated to increase the thermal stability of the CH3 domain of the respective solubly expressed proteins. Assessment of the stability of the libraries expressed on the surface of yeast cells by flow cytometry demonstrated that loop elongation was considerably better tolerated in the stabilized libraries. By using in silico loop reconstruction and mimicking randomization together with MD simulations the underlying molecular dynamics were investigated. In the presence of stabilizing stem residues the backbone flexibility of the engineered EF loop as well as the fluctuation between its accessible conformations were decreased. In addition the CD loop (but not the AB loop) and most of the framework regions were rigidified. The obtained data are discussed with respect to the design of Fcabs and available data on the relation between flexibility and affinity of CDR loops in Ig-like molecules. PMID:24792385

Creating stable stem regions for loop elongation in Fcabs - insights from combining yeast surface display, in silico loop reconstruction and molecular dynamics simulations.

PubMed

Hasenhindl, Christoph; Lai, Balder; Delgado, Javier; Traxlmayr, Michael W; Stadlmayr, Gerhard; Rüker, Florian; Serrano, Luis; Oostenbrink, Chris; Obinger, Christian

2014-09-01

Fcabs (Fc antigen binding) are crystallizable fragments of IgG where the C-terminal structural loops of the CH3 domain are engineered for antigen binding. For the design of libraries it is beneficial to know positions that will permit loop elongation to increase the potential interaction surface with antigen. However, the insertion of additional loop residues might impair the immunoglobulin fold. In the present work we have probed whether stabilizing mutations flanking the randomized and elongated loop region improve the quality of Fcab libraries. In detail, 13 libraries were constructed having the C-terminal part of the EF loop randomized and carrying additional residues (1, 2, 3, 5 or 10, respectively) in the absence and presence of two flanking mutations. The latter have been demonstrated to increase the thermal stability of the CH3 domain of the respective solubly expressed proteins. Assessment of the stability of the libraries expressed on the surface of yeast cells by flow cytometry demonstrated that loop elongation was considerably better tolerated in the stabilized libraries. By using in silico loop reconstruction and mimicking randomization together with MD simulations the underlying molecular dynamics were investigated. In the presence of stabilizing stem residues the backbone flexibility of the engineered EF loop as well as the fluctuation between its accessible conformations were decreased. In addition the CD loop (but not the AB loop) and most of the framework regions were rigidified. The obtained data are discussed with respect to the design of Fcabs and available data on the relation between flexibility and affinity of CDR loops in Ig-like molecules. Copyright © 2014. Published by Elsevier B.V.

RNA-Seq analysis to capture the transcriptome landscape of a single cell

PubMed Central

Tang, Fuchou; Barbacioru, Catalin; Nordman, Ellen; Xu, Nanlan; Bashkirov, Vladimir I; Lao, Kaiqin; Surani, M. Azim

2013-01-01

We describe here a protocol for digital transcriptome analysis in a single mouse blastomere using a deep sequencing approach. An individual blastomere was first isolated and put into lysate buffer by mouth pipette. Reverse transcription was then performed directly on the whole cell lysate. After this, the free primers were removed by Exonuclease I and a poly(A) tail was added to the 3′ end of the first-strand cDNA by Terminal Deoxynucleotidyl Transferase. Then the single cell cDNAs were amplified by 20 plus 9 cycles of PCR. Then 100-200 ng of these amplified cDNAs were used to construct a sequencing library. The sequencing library can be used for deep sequencing using the SOLiD system. Compared with the cDNA microarray technique, our assay can capture up to 75% more genes expressed in early embryos. The protocol can generate deep sequencing libraries within 6 days for 16 single cell samples. PMID:20203668

Bacterial Microcolonies in Gel Beads for High-Throughput Screening of Libraries in Synthetic Biology.

PubMed

Duarte, José M; Barbier, Içvara; Schaerli, Yolanda

2017-11-17

Synthetic biologists increasingly rely on directed evolution to optimize engineered biological systems. Applying an appropriate screening or selection method for identifying the potentially rare library members with the desired properties is a crucial step for success in these experiments. Special challenges include substantial cell-to-cell variability and the requirement to check multiple states (e.g., being ON or OFF depending on the input). Here, we present a high-throughput screening method that addresses these challenges. First, we encapsulate single bacteria into microfluidic agarose gel beads. After incubation, they harbor monoclonal bacterial microcolonies (e.g., expressing a synthetic construct) and can be sorted according their fluorescence by fluorescence activated cell sorting (FACS). We determine enrichment rates and demonstrate that we can measure the average fluorescent signals of microcolonies containing phenotypically heterogeneous cells, obviating the problem of cell-to-cell variability. Finally, we apply this method to sort a pBAD promoter library at ON and OFF states.

Construction of High-Quality Camel Immune Antibody Libraries.

PubMed

Romão, Ema; Poignavent, Vianney; Vincke, Cécile; Ritzenthaler, Christophe; Muyldermans, Serge; Monsion, Baptiste

2018-01-01

Single-domain antibodies libraries of heavy-chain only immunoglobulins from camelids or shark are enriched for high-affinity antigen-specific binders by a short in vivo immunization. Thus, potent binders are readily retrieved from relatively small-sized libraries of 10 7 -10 8 individual transformants, mostly after phage display and panning on a purified target. However, the remaining drawback of this strategy arises from the need to generate a dedicated library, for nearly every envisaged target. Therefore, all the procedures that shorten and facilitate the construction of an immune library of best possible quality are definitely a step forward. In this chapter, we provide the protocol to generate a high-quality immune VHH library using the Golden Gate Cloning strategy employing an adapted phage display vector where a lethal ccdB gene has to be substituted by the VHH gene. With this procedure, the construction of the library can be shortened to less than a week starting from bleeding the animal. Our libraries exceed 10 8 individual transformants and close to 100% of the clones harbor a phage display vector having an insert with the length of a VHH gene. These libraries are also more economic to make than previous standard approaches using classical restriction enzymes and ligations. The quality of the Nanobodies that are retrieved from immune libraries obtained by Golden Gate Cloning is identical to those from immune libraries made according to the classical procedure.

Construction of Professional Identity in Novice Library Media Specialists

ERIC Educational Resources Information Center

Sandford, Deborah W.

2013-01-01

The roles of the person who works in a school library, as well as their title--librarian, teacher-librarian, library teacher, library media specialist, school librarian, library media teacher--have undergone countless revisions since the first official school libraries opened their doors in the early 1900s. Although school library media…

Encoded Library Synthesis Using Chemical Ligation and the Discovery of sEH Inhibitors from a 334-Million Member Library

NASA Astrophysics Data System (ADS)

Litovchick, Alexander; Dumelin, Christoph E.; Habeshian, Sevan; Gikunju, Diana; Guié, Marie-Aude; Centrella, Paolo; Zhang, Ying; Sigel, Eric A.; Cuozzo, John W.; Keefe, Anthony D.; Clark, Matthew A.

2015-06-01

A chemical ligation method for construction of DNA-encoded small-molecule libraries has been developed. Taking advantage of the ability of the Klenow fragment of DNA polymerase to accept templates with triazole linkages in place of phosphodiesters, we have designed a strategy for chemically ligating oligonucleotide tags using cycloaddition chemistry. We have utilized this strategy in the construction and selection of a small molecule library, and successfully identified inhibitors of the enzyme soluble epoxide hydrolase.

Tolerance of the archaeal Sac7d scaffold protein to alternative library designs: characterization of anti-immunoglobulin G Affitins.

PubMed

Béhar, Ghislaine; Bellinzoni, Marco; Maillasson, Mike; Paillard-Laurance, Lauranne; Alzari, Pedro M; He, Xuemei; Mouratou, Barbara; Pecorari, Frédéric

2013-04-01

Engineered protein scaffolds have received considerable attention as alternatives to antibodies in both basic and applied research, as they can offer superior biophysical properties often associated with a simpler molecular organization. Sac7d has been demonstrated as an effective scaffold for molecular recognition. Here, we used the initial L1 'flat surface' library constructed by randomization of 14 residues, to identify ligands specific for human immunoglobulin G. To challenge the plasticity of the Sac7d protein scaffold, we designed the alternative L2 'flat surface & loops' library whereof only 10 residues are randomized. Representative binders (Affitins) of the two libraries exhibited affinities in the low nanomolar range and were able to recognize different epitopes within human immunoglobulin G. These Affitins were stable up to pH 12 while largely conserving other favorable properties of Sac7d protein, such as high expression yields in Escherichia coli, solubility, thermal stability up to 80.7°C, and acidic stability (pH 0). In agreement with our library designs, mutagenesis study revealed two distinct binding areas, one including loops. Together, our results indicate that the Sac7d scaffold tolerates alternative library designs, which further expands the diversity of Affitins and may provide a general way to create tailored affinity tools for demanding applications.

Capturing the 'ome': the expanding molecular toolbox for RNA and DNA library construction.

PubMed

Boone, Morgane; De Koker, Andries; Callewaert, Nico

2018-04-06

All sequencing experiments and most functional genomics screens rely on the generation of libraries to comprehensively capture pools of targeted sequences. In the past decade especially, driven by the progress in the field of massively parallel sequencing, numerous studies have comprehensively assessed the impact of particular manipulations on library complexity and quality, and characterized the activities and specificities of several key enzymes used in library construction. Fortunately, careful protocol design and reagent choice can substantially mitigate many of these biases, and enable reliable representation of sequences in libraries. This review aims to guide the reader through the vast expanse of literature on the subject to promote informed library generation, independent of the application.

High-Throughput Method for Ranking the Affinity of Peptide Ligands Selected from Phage Display Libraries

PubMed Central

González-Techera, A.; Umpiérrez-Failache, M.; Cardozo, S.; Obal, G.; Pritsch, O.; Last, J. A.; Gee, S. J.; Hammock, B. D.; González-Sapienza, G.

2010-01-01

The use of phage display peptide libraries allows rapid isolation of peptide ligands for any target selector molecule. However, due to differences in peptide expression and the heterogeneity of the phage preparations, there is no easy way to compare the binding properties of the selected clones, which operates as a major “bottleneck” of the technology. Here, we present the development of a new type of library that allows rapid comparison of the relative affinity of the selected peptides in a high-throughput screening format. As a model system, a phage display peptide library constructed on a phagemid vector that contains the bacterial alkaline phosphatase gene (BAP) was selected with an antiherbicide antibody. Due to the intrinsic switching capacity of the library, the selected peptides were transferred “en masse” from the phage coat protein to BAP. This was coupled to an optimized affinity ELISA where normalized amounts of the peptide–BAP fusion allow direct comparison of the binding properties of hundreds of peptide ligands. The system was validated by plasmon surface resonance experiments using synthetic peptides, showing that the method discriminates among the affinities of the peptides within 3 orders of magnitude. In addition, the peptide–BAP protein can find direct application as a tracer reagent. PMID:18393454

Identification and Functional Annotation of Genes Differentially Expressed in the Reproductive Tissues of the Olive Tree (Olea europaea L.) through the Generation of Subtractive Libraries

PubMed Central

Zafra, Adoración; Carmona, Rosario; Traverso, José A.; Hancock, John T.; Goldman, Maria H. S.; Claros, M. Gonzalo; Hiscock, Simon J.; Alche, Juan D.

2017-01-01

The olive tree is a crop of high socio-economical importance in the Mediterranean area. Sexual reproduction in this plant is an essential process, which determines the yield. Successful fertilization is mainly favored and sometimes needed of the presence of pollen grains from a different cultivar as the olive seizes a self-incompatibility system allegedly determined of the sporophytic type. The purpose of the present study was to identify key gene products involved in the function of olive pollen and pistil, in order to help elucidate the events and signaling processes, which happen during the courtship, pollen grain germination, and fertilization in olive. The use of subtractive SSH libraries constructed using, on the one hand one specific stage of the pistil development with germinating pollen grains, and on the other hand mature pollen grains may help to reveal the specific transcripts involved in the cited events. Such libraries have also been created by subtracting vegetative mRNAs (from leaves), in order to identify reproductive sequences only. A variety of transcripts have been identified in the mature pollen grains and in the pistil at the receptive stage. Among them, those related to defense, transport and oxidative metabolism are highlighted mainly in the pistil libraries where transcripts related to stress, and response to biotic and abiotic stimulus have a prominent position. Extensive lists containing information as regard to the specific transcripts determined for each stage and tissue are provided, as well as functional classifications of these gene products. Such lists were faced up to two recent datasets obtained in olive after transcriptomic and genomic approaches. The sequences and the differential expression level of the SSH-transcripts identified here, highly matched the transcriptomic information. Moreover, the unique presence of a representative number of these transcripts has been validated by means of qPCR approaches. The construction of SSH libraries using pistil and pollen, considering the high interaction between male-female counterparts, allowed the identification of transcripts with important roles in stigma physiology. The functions of many of the transcripts obtained are intimately related, and most of them are of pivotal importance in defense, pollen-stigma interaction and signaling. PMID:28955364

MicroRNA-focused CRISPR-Cas9 Library Screen Reveals Fitness-Associated miRNAs.

PubMed

Kurata, Jessica S; Lin, Ren-Jang

2018-05-02

MicroRNAs (miRNAs) are posttranscriptional gene regulators that play important roles in the control of cell fitness, differentiation, and development. The CRISPR-Cas9 gene-editing system is composed of the Cas9 nuclease in complex with a single guide RNA (sgRNA) and directs DNA cleavage at a predetermined site. Several CRISPR-Cas9 libraries have been constructed for genome-scale knockout screens of protein function; however few libraries have included miRNA genes. Here we constructed a miRNA-focused CRISPR-Cas9 library that targets 1,594 (85%) annotated human miRNA stem-loops. The sgRNAs in our LX-miR library are designed to have high on-target and low off-target activity, and each miRNA is targeted by 4-5 sgRNAs. We used this sgRNA library to screen for miRNAs that affect cell fitness of HeLa or NCI-N87 cells by monitoring the change in frequency of each sgRNA over time. By considering the expression in the tested cells and the dysregulation of the miRNAs in cancer specimens, we identified five HeLa pro-fitness and cervical cancer up-regulated miRNAs (miR-31-5p, miR-92b-3p, miR-146b-5p, miR-151a-3p, and miR-194-5p). Similarly, we identified six NCI-N87 pro-fitness and gastric cancer up-regulated miRNAs (miR-95-3p, miR-181a-5p, miR-188-5p, miR-196b-5p, miR-584-5p, and miR-1304-3p), as well as three anti-fitness and down-regulated miRNAs (let-7a-3p, miR-100-5p, and miR-149-5p). Some of those miRNAs are known to be oncogenic or tumor-suppressive, but others are novel. Taken together, the LX-miR library is useful for genome-wide unbiased screening to identify miRNAs important for cellular fitness and likely to be useful for other functional screens. Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Proposed Extension of the Library Services and Construction Act. Hearing before the Subcommittee on Select Education of the Committee on Education and Labor.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Committee on Education and Labor.

The text of oversight hearings on proposals to extend the Library Services and Construction Act (LSCA) includes presentations on the operation of programs authorized under the act. The measure, initially passed in 1964, has provided library services for those without access to them; these included the handicapped, hospitalized, disadvantaged…

SALP, a new single-stranded DNA library preparation method especially useful for the high-throughput characterization of chromatin openness states.

PubMed

Wu, Jian; Dai, Wei; Wu, Lin; Wang, Jinke

2018-02-13

Next-generation sequencing (NGS) is fundamental to the current biological and biomedical research. Construction of sequencing library is a key step of NGS. Therefore, various library construction methods have been explored. However, the current methods are still limited by some shortcomings. This study developed a new NGS library construction method, Single strand Adaptor Library Preparation (SALP), by using a novel single strand adaptor (SSA). SSA is a double-stranded oligonucleotide with a 3' overhang of 3 random nucleotides, which can be efficiently ligated to the 3' end of single strand DNA by T4 DNA ligase. SALP can be started with any denatured DNA fragments such as those sheared by Tn5 tagmentation, enzyme digestion and sonication. When started with Tn5-tagmented chromatin, SALP can overcome a key limitation of ATAC-seq and become a high-throughput NGS library construction method, SALP-seq, which can be used to comparatively characterize the chromatin openness state of multiple cells unbiasly. In this way, this study successfully characterized the comparative chromatin openness states of four different cell lines, including GM12878, HepG2, HeLa and 293T, with SALP-seq. Similarly, this study also successfully characterized the chromatin openness states of HepG2 cells with SALP-seq by using 10 5 to 500 cells. This study developed a new NGS library construction method, SALP, by using a novel kind of single strand adaptor (SSA), which should has wide applications in the future due to its unique performance.

[Construction of human phage antibody library and screening for human monoclonal antibodies of amylin].

PubMed

Gong, Qian; Li, Chang-ying; Chang, Ji-wu; Zhu, Tie-hong

2012-06-01

To screen monoclonal antibodies to amylin from a constructed human phage antibody library and identify their antigenic specificity and combining activities. The heavy chain Fd fragment and light chain of human immunoglobulin genes were amplified from peripheral blood lymphocytes of healthy donors using RT-PCR, and then inserted into phagemid pComb3XSS to generate a human phage antibody library. The insertion of light chain or heavy chain Fd genes were identified by PCR after the digestion of Sac I, Xba I, Xho Iand Spe I. One of positive clones was analyzed by DNA sequencing. The specific anti-amylin clones were screened from antibody library against human amylin antigens and then the positive clones were determined by Phage-ELISA analysis. A Fab phage antibody library with 0.8×10(8); members was constructed with the efficacy of about 70%. DNA sequence analysis indicated V(H); gene belonged to V(H);3 gene family and V(λ); gene belonged to the V(λ); gene family. Using human amylin as panning antigen, specific anti-amylin Fab antibodies were enriched by screening the library for three times. Phage-ELISA assay showed the positive clones had very good specificity to amylin antigen. The successful construction of a phage antibody library and the identification of anti-amylin Fab antibodies provide a basis for further study and preparation of human anti-amylin antibodies.

Low-frequency chimeric yeast artificial chromosome libraries from flow-sorted human chromosomes 16 and 21.

PubMed Central

McCormick, M K; Campbell, E; Deaven, L; Moyzis, R

1993-01-01

Construction of chromosome-specific yeast artificial chromosome (YAC) libraries from sorted chromosomes was undertaken (i) to eliminate drawbacks associated with first-generation total genomic YAC libraries, such as the high frequency of chimeric YACs, and (ii) to provide an alternative method for generating chromosome-specific YAC libraries in addition to isolating such collections from a total genomic library. Chromosome-specific YAC libraries highly enriched for human chromosomes 16 and 21 were constructed. By maximizing the percentage of fragments with two ligatable ends and performing yeast transformations with less than saturating amounts of DNA in the presence of carrier DNA, YAC libraries with a low percentage of chimeric clones were obtained. The smaller number of YAC clones in these chromosome-specific libraries reduces the effort involved in PCR-based screening and allows hybridization methods to be a manageable screening approach. Images PMID:8430075

Evaluation of the capability of the PCV2 genome to encode miRNAs: lack of viral miRNA expression in an experimental infection.

PubMed

Núñez-Hernández, Fernando; Pérez, Lester J; Vera, Gonzalo; Córdoba, Sarai; Segalés, Joaquim; Sánchez, Armand; Núñez, José I

2015-05-01

Porcine circovirus type 2 (PCV2) is a ssDNA virus causing PCV2-systemic disease (PCV2-SD), one of the most important diseases in swine. MicroRNAs (miRNAs) are a new class of small non-coding RNAs that regulate gene expression post-transcriptionally. Viral miRNAs have recently been described and the number of viral miRNAs has been increasing in the past few years. In this study, small RNA libraries were constructed from two tissues of subclinically PCV2 infected pigs to explore if PCV2 can encode viral miRNAs. The deep sequencing data revealed that PCV2 does not express miRNAs in an in vivo subclinical infection.

Encoded Library Synthesis Using Chemical Ligation and the Discovery of sEH Inhibitors from a 334-Million Member Library

PubMed Central

Litovchick, Alexander; Dumelin, Christoph E.; Habeshian, Sevan; Gikunju, Diana; Guié, Marie-Aude; Centrella, Paolo; Zhang, Ying; Sigel, Eric A.; Cuozzo, John W.; Keefe, Anthony D.; Clark, Matthew A.

2015-01-01

A chemical ligation method for construction of DNA-encoded small-molecule libraries has been developed. Taking advantage of the ability of the Klenow fragment of DNA polymerase to accept templates with triazole linkages in place of phosphodiesters, we have designed a strategy for chemically ligating oligonucleotide tags using cycloaddition chemistry. We have utilized this strategy in the construction and selection of a small molecule library, and successfully identified inhibitors of the enzyme soluble epoxide hydrolase. PMID:26061191

Public Library Materials Conservation Project.

ERIC Educational Resources Information Center

Lowell, Howard P.

The Massachusetts Public Library Materials Conservation Project was a year-long program sponsored by the Massachusetts Bureau of Library Extension and conducted by the New England document Conservation Center (NEDCC) under a grant from Title I, Library Services and Construction Act. Its purposes were to provide public library administrators,…

Expressed sequence tags from heat-shocked seagrass Zostera noltii (Hornemann) from its southern distribution range.

PubMed

Massa, Sónia I; Pearson, Gareth A; Aires, Tânia; Kube, Michael; Olsen, Jeanine L; Reinhardt, Richard; Serrão, Ester A; Arnaud-Haond, Sophie

2011-09-01

Predicted global climate change threatens the distributional ranges of species worldwide. We identified genes expressed in the intertidal seagrass Zostera noltii during recovery from a simulated low tide heat-shock exposure. Five Expressed Sequence Tag (EST) libraries were compared, corresponding to four recovery times following sub-lethal temperature stress, and a non-stressed control. We sequenced and analyzed 7009 sequence reads from 30min, 2h, 4h and 24h after the beginning of the heat-shock (AHS), and 1585 from the control library, for a total of 8594 sequence reads. Among 51 Tentative UniGenes (TUGs) exhibiting significantly different expression between libraries, 19 (37.3%) were identified as 'molecular chaperones' and were over-expressed following heat-shock, while 12 (23.5%) were 'photosynthesis TUGs' generally under-expressed in heat-shocked plants. A time course analysis of expression showed a rapid increase in expression of the molecular chaperone class, most of which were heat-shock proteins; which increased from 2 sequence reads in the control library to almost 230 in the 30min AHS library, followed by a slow decrease during further recovery. In contrast, 'photosynthesis TUGs' were under-expressed 30min AHS compared with the control library, and declined progressively with recovery time in the stress libraries, with a total of 29 sequence reads 24h AHS, compared with 125 in the control. A total of 4734 TUGs were screened for EST-Single Sequence Repeats (EST-SSRs) and 86 microsatellites were identified. Copyright © 2011 Elsevier B.V. All rights reserved.

Directed combinatorial mutagenesis of Escherichia coli for complex phenotype engineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Rongming; Liang, Liya; Garst, Andrew D.

Strain engineering for industrial production requires a targeted improvement of multiple complex traits, which range from pathway flux to tolerance to mixed sugar utilization. Here, we report the use of an iterative CRISPR EnAbled Trackable genome Engineering (iCREATE) method to engineer rapid glucose and xylose co-consumption and tolerance to hydrolysate inhibitors in E. coli. Deep mutagenesis libraries were rationally designed, constructed, and screened to target ~40,000 mutations across 30 genes. These libraries included global and high-level regulators that regulate global gene expression, transcription factors that play important roles in genome-level transcription, enzymes that function in the sugar transport system, NAD(P)Hmore » metabolism, and the aldehyde reduction system. Specific mutants that conferred increased growth in mixed sugars and hydrolysate tolerance conditions were isolated, confirmed, and evaluated for changes in genome-wide expression levels. As a result, we tested the strain with positive combinatorial mutations for 3-hydroxypropionic acid (3HP) production under high furfural and high acetate hydrolysate fermentation, which demonstrated a 7- and 8-fold increase in 3HP productivity relative to the parent strain, respectively.« less

Directed combinatorial mutagenesis of Escherichia coli for complex phenotype engineering

DOE PAGES

Liu, Rongming; Liang, Liya; Garst, Andrew D.; ...

2018-03-29

Strain engineering for industrial production requires a targeted improvement of multiple complex traits, which range from pathway flux to tolerance to mixed sugar utilization. Here, we report the use of an iterative CRISPR EnAbled Trackable genome Engineering (iCREATE) method to engineer rapid glucose and xylose co-consumption and tolerance to hydrolysate inhibitors in E. coli. Deep mutagenesis libraries were rationally designed, constructed, and screened to target ~40,000 mutations across 30 genes. These libraries included global and high-level regulators that regulate global gene expression, transcription factors that play important roles in genome-level transcription, enzymes that function in the sugar transport system, NAD(P)Hmore » metabolism, and the aldehyde reduction system. Specific mutants that conferred increased growth in mixed sugars and hydrolysate tolerance conditions were isolated, confirmed, and evaluated for changes in genome-wide expression levels. As a result, we tested the strain with positive combinatorial mutations for 3-hydroxypropionic acid (3HP) production under high furfural and high acetate hydrolysate fermentation, which demonstrated a 7- and 8-fold increase in 3HP productivity relative to the parent strain, respectively.« less

CRISPR/Cas9-mediated gene knockout screens and target identification via whole-genome sequencing uncover host genes required for picornavirus infection.

PubMed

Kim, Heon Seok; Lee, Kyungjin; Bae, Sangsu; Park, Jeongbin; Lee, Chong-Kyo; Kim, Meehyein; Kim, Eunji; Kim, Minju; Kim, Seokjoong; Kim, Chonsaeng; Kim, Jin-Soo

2017-06-23

Several groups have used genome-wide libraries of lentiviruses encoding small guide RNAs (sgRNAs) for genetic screens. In most cases, sgRNA expression cassettes are integrated into cells by using lentiviruses, and target genes are statistically estimated by the readout of sgRNA sequences after targeted sequencing. We present a new virus-free method for human gene knockout screens using a genome-wide library of CRISPR/Cas9 sgRNAs based on plasmids and target gene identification via whole-genome sequencing (WGS) confirmation of authentic mutations rather than statistical estimation through targeted amplicon sequencing. We used 30,840 pairs of individually synthesized oligonucleotides to construct the genome-scale sgRNA library, collectively targeting 10,280 human genes ( i.e. three sgRNAs per gene). These plasmid libraries were co-transfected with a Cas9-expression plasmid into human cells, which were then treated with cytotoxic drugs or viruses. Only cells lacking key factors essential for cytotoxic drug metabolism or viral infection were able to survive. Genomic DNA isolated from cells that survived these challenges was subjected to WGS to directly identify CRISPR/Cas9-mediated causal mutations essential for cell survival. With this approach, we were able to identify known and novel genes essential for viral infection in human cells. We propose that genome-wide sgRNA screens based on plasmids coupled with WGS are powerful tools for forward genetics studies and drug target discovery. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Expressed sequence tags from poplar wood tissues--a comparative analysis from multiple libraries.

PubMed

Déjardin, A; Leplé, J-C; Lesage-Descauses, M-C; Costa, G; Pilate, G

2004-01-01

Xylogenesis involves successive developmental processes--cambial division, cell expansion and differentiation, cell death--each occurring along a gradient from the cambium to the pith of the stem. Taking advantage of the high level of organisation of wood tissues, we isolated cambial zone (CZ), differentiating xylem (DX) and mature xylem (MX) from both tension wood (TW) and opposite wood (OW) of bent poplars. Four different cDNA libraries were then constructed and used to generate 10,062 EST, reflecting the genes expressed in the different wood tissues. For the most abundant clusters, the EST distributions were compared between libraries in order to identify genes specific or over-represented at some specific developmental stages. They clearly showed a developmental shift between CZ and DX, whereas there is a continuity of development between DX and MX. CZ was mainly characterized by clusters of genes involved in cell cycle, protein synthesis and fate. Interestingly, two clusters with no assigned function were found specific to the cambial zone. In DX and MX, clusters were mostly involved in methylation of lignin precursors and microtubule cytoskeleton. In addition, in DX, EST from TW and OW were compared: five clusters of arabinogalactan proteins, one for sucrose synthase and one for fructokinase were specific or over-represented in TW. Moreover, a putative transcription factor and a cluster of unknown function were also identified in DX-TW. The informative comparison of multiple libraries prepared from wood tissues led to the identification of genes--some with still unknown functions--putatively involved in xylogenesis and tension wood formation.

Identification of genes differentially expressed during adventitious shoot induction in Pinus pinea cotyledons by subtractive hybridization and quantitative PCR.

PubMed

Alonso, Pablo; Cortizo, Millán; Cantón, Francisco R; Fernández, Belén; Rodríguez, Ana; Centeno, Maria L; Cánovas, Francisco M; Ordás, Ricardo J

2007-12-01

As part of a study aimed at understanding the physiological and molecular mechanisms involved in adventitious shoot bud formation in pine cotyledons, we conducted a transcriptome analysis to identify early-induced genes during the first phases of adventitious caulogenesis in Pinus pinea L. cotyledons cultured in the presence of benzyladenine. A subtractive cDNA library with more than 700 clones was constructed. Of these clones, 393 were sequenced, analyzed and grouped according to their putative function. Quantitative real-time PCR analysis was performed to confirm the differential expression of 30 candidate genes. Results are contrasted with available data for other species.

Comprehensive Long-Range Program for Library Services in Wisconsin.

ERIC Educational Resources Information Center

Wisconsin State Dept. of Public Instruction, Madison. Div. of Library Services.

The main areas of concern in this long-range development program to meet the requirements of the Library Services and Construction Act are the following: public library development and facilities, public library services for the disadvantaged, library services for the blind, physically handicapped and institutionalized persons, intertype library…

Library Buildings and Equipment Section. Management and Technology Division. Papers.

ERIC Educational Resources Information Center

International Federation of Library Associations, The Hague (Netherlands).

Papers on library buildings and equipment, which were presented at the 1983 International Federation of Library Associations (IFLA) conference, include: (1) "The Impact of Technology on Library Buildings," in which Rolf Fuhlrott (West Germany) discusses construction technology (types of building materials and library building design),…

Public Library Site Evaluation and Location: Past and Present Market-Based Modelling Tools for the Future.

ERIC Educational Resources Information Center

Koontz, Christine M.

1992-01-01

Presents a methodology for construction of location modeling for public library facilities in diverse urban environments. Historical and current research in library location is reviewed; and data collected from a survey of six library systems are analyzed according to population, spatial, library use, and library attractiveness variables. (48…

Generation, Annotation, and Analysis of a Large-Scale Expressed Sequence Tag Library from Arabidopsis pumila to Explore Salt-Responsive Genes.

PubMed

Huang, Xianzhong; Yang, Lifei; Jin, Yuhuan; Lin, Jun; Liu, Fang

2017-01-01

Arabidopsis pumila is an ephemeral plant, and a close relative of the model plant Arabidopsis thaliana , but it possesses higher photosynthetic efficiency, higher propagation rate, and higher salinity tolerance compared to those A. thaliana , thus providing a candidate plant system for gene mining for environmental adaption and salt tolerance. However, A. pumila is an under-explored resource for understanding the genetic mechanisms underlying abiotic stress adaptation. To improve our understanding of the molecular and genetic mechanisms of salt stress adaptation, more than 19,900 clones randomly selected from a cDNA library constructed previously from leaf tissue exposed to high-salinity shock were sequenced. A total of 16,014 high-quality expressed sequence tags (ESTs) were generated, which have been deposited in the dbEST GenBank under accession numbers JZ932319 to JZ948332. Clustering and assembly of these ESTs resulted in the identification of 8,835 unique sequences, consisting of 2,469 contigs and 6,366 singletons. The blastx results revealed 8,011 unigenes with significant similarity to known genes, while only 425 unigenes remained uncharacterized. Functional classification demonstrated an abundance of unigenes involved in binding, catalytic, structural or transporter activities, and in pathways of energy, carbohydrate, amino acid, or lipid metabolism. At least seven main classes of genes were related to salt-tolerance among the 8,835 unigenes. Many previously reported salt tolerance genes were also manifested in this library, for example VP1, H + -ATPase, NHX1, SOS2, SOS3, NAC, MYB, ERF, LEA, P5CS1 . In addition, 251 transcription factors were identified from the library, classified into 42 families. Lastly, changes in expression of the 12 most abundant unigenes, 12 transcription factor genes, and 19 stress-related genes in the first 24 h of exposure to high-salinity stress conditions were monitored by qRT-PCR. The large-scale EST library obtained in this study provides first-hand information on gene sequences expressed in young leaves of A. pumila exposed to salt shock. The rapid discovery of known or unknown genes related to salinity stress response in A. pumila will facilitate the understanding of complex adaptive mechanisms for ephemerals.

Differential mantle transcriptomics and characterization of growth-related genes in the diploid and triploid pearl oyster Pinctada fucata.

PubMed

Guan, Yunyan; He, Maoxian; Wu, Houbo

2017-06-01

To explore the molecular mechanism of triploidy effect in the pearl oyster Pinctada fucata, two RNA-seq libraries were constructed from the mantle tissue of diploids and triploids by Roche-454 massive parallel pyrosequencing. The identification of differential expressed genes (DEGs) between diploid and triploid may reveal the molecular mechanism of triploidy effect. In this study, 230 down-regulated and 259 up-regulated DEGs were obtained by comparison between diploid and triploid libraries. The gene ontology and KEGG pathway analysis revealed more functional activation in triploids and it may due to the duplicated gene expression in transcriptional level during whole genome duplication (WGD). To confirm the sequencing data, a set of 11 up-regulated genes related to growth and development control and regulation were analyzed by RT-qPCR in independent experiment. According to the validation and annotation of these genes, it is hypothesized that the set of up-regulated expressed genes had the correlated expression pattern involved in shell building or other interactive probable functions during triploidization. The up- regulation of growth-related genes may support the classic hypotheses of 'energy redistribution' from early research. The results provide valuable resources to understand the molecular mechanism of triploidy effect in both shell building and producing high-quality seawater pearls. Copyright © 2017 Elsevier B.V. All rights reserved.

An integrated vector system for cellular studies of phage display-derived peptides.

PubMed

Voss, Stephan D; DeGrand, Alec M; Romeo, Giulio R; Cantley, Lewis C; Frangioni, John V

2002-09-15

Peptide phage display is a method by which large numbers of diverse peptides can be screened for binding to a target of interest. Even when successful, the rate-limiting step is usually validation of peptide bioactivity using living cells. In this paper, we describe an integrated system of vectors that expedites both the screening and the characterization processes. Library construction and screening is performed using an optimized type 3 phage display vector, mJ(1), which is shown to accept peptide libraries of at least 23 amino acids in length. Peptide coding sequences are shuttled from mJ(1) into one of three families of mammalian expression vectors for cell physiological studies. The vector pAL(1) expresses phage display-derived peptides as Gal4 DNA binding domain fusion proteins for transcriptional activation studies. The vectors pG(1), pG(1)N, and pG(1)C express phage display-derived peptides as green fluorescent protein fusions targeted to the entire cell, nucleus, or cytoplasm, respectively. The vector pAP(1) expresses phage display-derived peptides as fusions to secreted placental alkaline phosphatase. Such enzyme fusions can be used as highly sensitive affinity reagents for high-throughput assays and for cloning of peptide-binding cell surface receptors. Taken together, this system of vectors should facilitate the development of phage display-derived peptides into useful biomolecules.

Efficient and simpler method to construct normalized cDNA libraries with improved representations of full-length cDNAs

DOEpatents

Soares, Marcelo Bento; Bonaldo, Maria de Fatima

1998-01-01

This invention provides a method to normalize a cDNA library comprising: (a) constructing a directionally cloned library containing cDNA inserts wherein the insert is capable of being amplified by polymerase chain reaction; (b) converting a double-stranded cDNA library into single-stranded DNA circles; (c) generating single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) by polymerase chain reaction with appropriate primers; (d) hybridizing the single-stranded DNA circles converted in step (b) with the complementary single-stranded nucleic acid molecules generated in step (c) to produce partial duplexes to an appropriate Cot; and (e) separating the unhybridized single-stranded DNA circles from the hybridized DNA circles, thereby generating a normalized cDNA library. This invention also provides a method to normalize a cDNA library wherein the generating of single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) is by excising cDNA inserts from the double-stranded cDNA library; purifying the cDNA inserts from cloning vectors; and digesting the cDNA inserts with an exonuclease. This invention further provides a method to construct a subtractive cDNA library following the steps described above. This invention further provides normalized and/or subtractive cDNA libraries generated by the above methods.

Efficient and simpler method to construct normalized cDNA libraries with improved representations of full-length cDNAs

DOEpatents

Soares, M.B.; Fatima Bonaldo, M. de

1998-12-08

This invention provides a method to normalize a cDNA library comprising: (a) constructing a directionally cloned library containing cDNA inserts wherein the insert is capable of being amplified by polymerase chain reaction; (b) converting a double-stranded cDNA library into single-stranded DNA circles; (c) generating single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) by polymerase chain reaction with appropriate primers; (d) hybridizing the single-stranded DNA circles converted in step (b) with the complementary single-stranded nucleic acid molecules generated in step (c) to produce partial duplexes to an appropriate Cot; and (e) separating the unhybridized single-stranded DNA circles from the hybridized DNA circles, thereby generating a normalized cDNA library. This invention also provides a method to normalize a cDNA library wherein the generating of single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) is by excising cDNA inserts from the double-stranded cDNA library; purifying the cDNA inserts from cloning vectors; and digesting the cDNA inserts with an exonuclease. This invention further provides a method to construct a subtractive cDNA library following the steps described above. This invention further provides normalized and/or subtractive cDNA libraries generated by the above methods. 25 figs.

cDNA Cloning, expression and characterization of an allergenic 60s ribosomal protein of almond (prunus dulcis).

PubMed

Abolhassani, Mohsen; Roux, Kenneth H

2009-06-01

Tree nuts, including almond (prunus dulcis) are a source of food allergens often associated with life-threatening allergic reactions in susceptible individuals. Although the proteins in almonds have been biochemically characterized, relatively little has been reported regarding the identity of the allergens involved in almond sensitivity. The present study was undertaken to identify the allergens of the almond by cDNA library approach. cDNA library of almond seeds was constructed in Uni-Zap XR lamda vector and expressed in E. coli XL-1 blue. Plaques were immunoscreened with pooled sera of allergic patients. The cDNA clone reacting significantly with specific IgE antibodies was selected and subcloned and subsequently expressed in E. coli. The amino acids deducted from PCR product of clone showed homology to 60s acidic ribosomal protein of almond. The expressed protein was 11,450 Dalton without leader sequence. Immunoreactivity of the recombinant 60s ribosomal protein (r60sRP) was evaluated with dot blot analysis using pooled and individual sera of allergic patients. The data showed that r60sRP and almond extract (as positive control) possess the ability to bind the IgE antibodies. The results showed that expressed protein is an almond allergen.Whether this r60sRP represents a major allergen of almond needs to be further studied which requires a large number of sera from the almond atopic patients and also need to determine the IgE-reactive frequencies of each individual allergen.

Functional role of pyruvate kinase from Lactobacillus bulgaricus in acid tolerance and identification of its transcription factor by bacterial one-hybrid

PubMed Central

Zhai, Zhengyuan; An, Haoran; Wang, Guohong; Luo, Yunbo; Hao, Yanling

2015-01-01

Lactobacillus delbrueckii subsp. bulgaricus develops acid tolerance response when subjected to acid stress conditions, such as the induction of enzymes associated with carbohydrate metabolism. In this study, pyk gene encoding pyruvate kinase was over-expressed in heterologous host Lactococcus lactis NZ9000, and SDS-PAGE analysis revealed the successful expression of this gene in NZ9000. The survival rate of Pyk-overproducing strain was 45-fold higher than the control under acid stress condition (pH 4.0). In order to determine the transcription factor (TF) which regulates the expression of pyk by bacterial one-hybrid, we constructed a TF library including 65 TFs of L. bulgaricus. Western blotting indicated that TFs in this library could be successfully expressed in host strains. Subsequently, the promoter of pfk-pyk operon in L. bulgaricus was identified by 5′-RACE PCR. The bait plasmid pH3U3-p01 carrying the deletion fragment of pfk-pyk promoter captured catabolite control protein A (CcpA) which could regulate the expression of pyk by binding to a putative catabolite-responsive element (5′-TGTAAGCCCTAACA-3′) upstream the -35 region. Real-time qPCR analysis revealed the transcription of pyk was positively regulated by CcpA. This is the first report about identifying the TF of pyk in L. bulgaricus, which will provide new insight into the regulatory network. PMID:26581248

Genome-Wide Identification of miRNAs Responsive to Drought in Peach (Prunus persica) by High-Throughput Deep Sequencing

PubMed Central

Eldem, Vahap; Çelikkol Akçay, Ufuk; Ozhuner, Esma; Bakır, Yakup; Uranbey, Serkan; Unver, Turgay

2012-01-01

Peach (Prunus persica L.) is one of the most important worldwide fresh fruits. Since fruit growth largely depends on adequate water supply, drought stress is considered as the most important abiotic stress limiting fleshy fruit production and quality in peach. Plant responses to drought stress are regulated both at transcriptional and post-transcriptional level. As post-transcriptional gene regulators, miRNAs (miRNAs) are small (19–25 nucleotides in length), endogenous, non-coding RNAs. Recent studies indicate that miRNAs are involved in plant responses to drought. Therefore, Illumina deep sequencing technology was used for genome-wide identification of miRNAs and their expression profile in response to drought in peach. In this study, four sRNA libraries were constructed from leaf control (LC), leaf stress (LS), root control (RC) and root stress (RS) samples. We identified a total of 531, 471, 535 and 487 known mature miRNAs in LC, LS, RC and RS libraries, respectively. The expression level of 262 (104 up-regulated, 158 down-regulated) of the 453 miRNAs changed significantly in leaf tissue, whereas 368 (221 up-regulated, 147 down-regulated) of the 465 miRNAs had expression levels that changed significantly in root tissue upon drought stress. Additionally, a total of 197, 221, 238 and 265 novel miRNA precursor candidates were identified from LC, LS, RC and RS libraries, respectively. Target transcripts (137 for LC, 133 for LS, 148 for RC and 153 for RS) generated significant Gene Ontology (GO) terms related to DNA binding and catalytic activites. Genome-wide miRNA expression analysis of peach by deep sequencing approach helped to expand our understanding of miRNA function in response to drought stress in peach and Rosaceae. A set of differentially expressed miRNAs could pave the way for developing new strategies to alleviate the adverse effects of drought stress on plant growth and development. PMID:23227166

1991 survey of recent health sciences library building projects.

PubMed Central

Ludwig, L T

1992-01-01

Twenty health sciences libraries reported building planning, expansion, or construction of new facilities in the association's second annual survey of recent building projects. Six projects are new, freestanding structures in which the library occupies all or a major portion of the space. Six other projects are part of new construction for separately administered units in which the library is a major tenant. The final eight projects involve additions to or renovations of existing space. Seven of these twenty libraries were still in projected, predesign, or design stages of awaiting funding approval; of those seven, five were not prepared to release the requested information. Six projects are reported here as illustrative of current building projects. Images PMID:1600420

Fluorescent in situ sequencing (FISSEQ) of RNA for gene expression profiling in intact cells and tissues

PubMed Central

Lee, Je Hyuk; Daugharthy, Evan R.; Scheiman, Jonathan; Kalhor, Reza; Ferrante, Thomas C.; Terry, Richard; Turczyk, Brian M.; Yang, Joyce L.; Lee, Ho Suk; Aach, John; Zhang, Kun; Church, George M.

2014-01-01

RNA sequencing measures the quantitative change in gene expression over the whole transcriptome, but it lacks spatial context. On the other hand, in situ hybridization provides the location of gene expression, but only for a small number of genes. Here we detail a protocol for genome-wide profiling of gene expression in situ in fixed cells and tissues, in which RNA is converted into cross-linked cDNA amplicons and sequenced manually on a confocal microscope. Unlike traditional RNA-seq our method enriches for context-specific transcripts over house-keeping and/or structural RNA, and it preserves the tissue architecture for RNA localization studies. Our protocol is written for researchers experienced in cell microscopy with minimal computing skills. Library construction and sequencing can be completed within 14 d, with image analysis requiring an additional 2 d. PMID:25675209

Triazophos up-regulated gene expression in the female brown planthopper, Nilaparvata lugens.

PubMed

Bao, Yan-Yuan; Li, Bao-Ling; Liu, Zhao-Bu; Xue, Jian; Zhu, Zeng-Rong; Cheng, Jia-An; Zhang, Chuan-Xi

2010-09-01

The widespread use of insecticides has caused the resurgence of the brown planthopper, Nilaparvata lugens, in Asia. In this study, we investigated an organo-phosphorous insecticide, triazophos, and its ability to induce gene expression variation in female N. lugens nymphs just before emergence. By using the suppression subtractive hybridization method, a triazophos-induced cDNA library was constructed. In total, 402 differentially expressed cDNA clones were obtained. Real-time qPCR analysis confirmed that triazophos up-regulated the expression of six candidate genes at the transcript level in nymphs on day 3 of the 5th instar. These genes encode N. lugens vitellogenin, bystin, multidrug resistance protein (MRP), purine nucleoside phosphorylase (PNP), pyrroline-5-carboxylate reductase (P5CR) and carboxylesterase. Our results imply that the up-regulation of these genes may be involved in the induction of N. lugens female reproduction or resistance to insecticides.

Differentially expressed genes of Tetrahymena thermophila in response to tributyltin (TBT) identified by suppression subtractive hybridization and real time quantitative PCR.

PubMed

Feng, Lifang; Miao, Wei; Wu, Yuxuan

2007-02-15

Tributyltin (TBT) is widely used as antifouling paints, agriculture biocides, and plastic stabilizers around the world, resulting in great pollution problem in aquatic environments. However, it has been short of the biomonitor to detect TBT in freshwater. We constructed the suppression subtractive hybridization library of Tetrahymena thermophila exposed to TBT, and screened out 101 Expressed Sequence Tags whose expressions were significantly up- or down-regulated with TBT treatment. From this, a series of genes related to the TBT toxicity were discovered, such as glutathione-S-transferase gene (down-regulated), plasma membrane Ca2+ ATPase isoforms 3 gene (up-regulated) and NgoA (up-regulated). Furthermore, their expressions under different concentrations of TBT treatment (0.5-40 ppb) were detected by real time fluorescent quantitative PCR. The differentially expressed genes of T. thermophila in response to TBT were identified, which provide the basic to make Tetrahymena as a sensitive, rapid and convenient TBT biomonitor in freshwater based on rDNA inducible expression system.

Rapid Isolation of Antibody from a Synthetic Human Antibody Library by Repeated Fluorescence-Activated Cell Sorting (FACS)

PubMed Central

Yim, Sung Sun; Bang, Hyun Bae; Kim, Young Hwan; Lee, Yong Jae; Jeong, Gu Min; Jeong, Ki Jun

2014-01-01

Antibodies and their derivatives are the most important agents in therapeutics and diagnostics. Even after the significant progress in the technology for antibody screening from huge libraries, it takes a long time to isolate an antibody, which prevents a prompt action against the spread of a disease. Here, we report a new strategy for isolating desired antibodies from a combinatorial library in one day by repeated fluorescence-activated cell sorting (FACS). First, we constructed a library of synthetic human antibody in which single-chain variable fragment (scFv) was expressed in the periplasm of Escherichia coli. After labeling the cells with fluorescent antigen probes, the highly fluorescent cells were sorted by using a high-speed cell sorter, and these cells were reused without regeneration in the next round of sorting. After repeating this sorting, the positive clones were completely enriched in several hours. Thus, we screened the library against three viral antigens, including the H1N1 influenza virus, Hepatitis B virus, and Foot-and-mouth disease virus. Finally, the potential antibody candidates, which show KD values between 10 and 100 nM against the target antigens, could be successfully isolated even though the library was relatively small (∼106). These results show that repeated FACS screening without regeneration of the sorted cells can be a powerful method when a rapid response to a spreading disease is required. PMID:25303314

Sort-Seq Approach to Engineering a Formaldehyde-Inducible Promoter for Dynamically Regulated Escherichia coli Growth on Methanol

PubMed Central

2017-01-01

Tight and tunable control of gene expression is a highly desirable goal in synthetic biology for constructing predictable gene circuits and achieving preferred phenotypes. Elucidating the sequence–function relationship of promoters is crucial for manipulating gene expression at the transcriptional level, particularly for inducible systems dependent on transcriptional regulators. Sort-seq methods employing fluorescence-activated cell sorting (FACS) and high-throughput sequencing allow for the quantitative analysis of sequence–function relationships in a robust and rapid way. Here we utilized a massively parallel sort-seq approach to analyze the formaldehyde-inducible Escherichia coli promoter (Pfrm) with single-nucleotide resolution. A library of mutated formaldehyde-inducible promoters was cloned upstream of gfp on a plasmid. The library was partitioned into bins via FACS on the basis of green fluorescent protein (GFP) expression level, and mutated promoters falling into each expression bin were identified with high-throughput sequencing. The resulting analysis identified two 19 base pair repressor binding sites, one upstream of the −35 RNA polymerase (RNAP) binding site and one overlapping with the −10 site, and assessed the relative importance of each position and base therein. Key mutations were identified for tuning expression levels and were used to engineer formaldehyde-inducible promoters with predictable activities. Engineered variants demonstrated up to 14-fold lower basal expression, 13-fold higher induced expression, and a 3.6-fold stronger response as indicated by relative dynamic range. Finally, an engineered formaldehyde-inducible promoter was employed to drive the expression of heterologous methanol assimilation genes and achieved increased biomass levels on methanol, a non-native substrate of E. coli. PMID:28463494

Generation and Analysis of Expressed Sequence Tags from Olea europaea L.

PubMed Central

Ozdemir Ozgenturk, Nehir; Oruç, Fatma; Sezerman, Ugur; Kuçukural, Alper; Vural Korkut, Senay; Toksoz, Feriha; Un, Cemal

2010-01-01

Olive (Olea europaea L.) is an important source of edible oil which was originated in Near-East region. In this study, two cDNA libraries were constructed from young olive leaves and immature olive fruits for generation of ESTs to discover the novel genes and search the function of unknown genes of olive. The randomly selected 3840 colonies were sequenced for EST collection from both libraries. Readable 2228 sequences for olive leaf and 1506 sequences for olive fruit were assembled into 205 and 69 contigs, respectively, whereas 2478 were singletons. Putative functions of all 2752 differentially expressed unique sequences were designated by gene homology based on BLAST and annotated using BLAST2GO. While 1339 ESTs show no homology to the database, 2024 ESTs have homology (under 80%) with hypothetical proteins, putative proteins, expressed proteins, and unknown proteins in NCBI-GenBank. 635 EST's unique genes sequence have been identified by over 80% homology to known function in other species which were not previously described in Olea family. Only 3.1% of total EST's was shown similarity with olive database existing in NCBI. This generated EST's data and consensus sequences were submitted to NCBI as valuable source for functional genome studies of olive. PMID:21197085

The mining of pearl formation genes in pearl oyster Pinctada fucata by cDNA suppression subtractive hybridization.

PubMed

Wang, Ning; Kinoshita, Shigeharu; Nomura, Naoko; Riho, Chihiro; Maeyama, Kaoru; Nagai, Kiyohito; Watabe, Shugo

2012-04-01

Recent researches revealed the regional preference of biomineralization gene transcription in the pearl oyster Pinctada fucata: it transcribed mainly the genes responsible for nacre secretion in mantle pallial, whereas the ones regulating calcite shells expressed in mantle edge. This study took use of this character and constructed the forward and reverse suppression subtractive hybridization (SSH) cDNA libraries. A total of 669 cDNA clones were sequenced and 360 expressed sequence tags (ESTs) greater than 100 bp were generated. Functional annotation associated 95 ESTs with specific functions, and 79 among them were identified from P. fucata at the first time. In the forward SSH cDNA library, it recognized mass amount of nacre protein genes, biomineralization genes dominantly expressed in the mantle pallial, calcium-ion-binding genes, and other biomineralization-related genes important for pearl formation. Real-time PCR showed that all the examined genes were distributed in oyster mantle tissues with a consistence to the SSH design. The detection of their RNA transcripts in pearl sac confirmed that the identified genes were certainly involved in pearl formation. Therefore, the data from this work will initiate a new round of pearl formation gene study and shed new insights into molluscan biomineralization.

A Review and Evaluation of the Illinois State Library Scholarship Program, 1961-1980. Report No. 7.

ERIC Educational Resources Information Center

Drone, Jeanette M.

From 1961-1980, the Illinois State Library (ISL) awarded scholarships using Library Services Act (LSA) and Library Services and Construction Act (LSCA) funds. The purpose was to recruit talented college graduates to the library profession and to retain these individuals in Illinois libraries. Of the 212 individuals who received scholarships, 198…

A Five Year Plan; Pennsylvania Library Development, 1971-1976.

ERIC Educational Resources Information Center

Pennsylvania State Library, Harrisburg.

The objective of Pennsylvania's State Plan for use of Library Services and Construction Act (LSCA) funds is continued development of a statewide system of libraries so that good quality, free, convenient, public library service will be available to every resident of the state. The system consists of: (1) local libraries or bookmobile stops so…

Wayne Township Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Smyth, Carol B.; Grannell, Dorothy S.; Moore, Miriam

The Literacy Resource Center project, a program of the Wayne Township Public Library also known as the Morrisson-Reeves Library (Richmond, Indiana), involved recruitment, retention, coalition building, public awareness, training, basic literacy, collection development, tutoring, computer-assisted, other technology, employment oriented,…

Jackson District Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Rosynek, Joy

This final performance report provides project outcome information and data to the U.S. Department of Education for the federally-funded Library Literacy Program. The Jackson District Library (Michigan) conducted a project that involved recruitment, retention, public awareness, training, basic literacy, collection development, tutoring, employment…

Library Programs. Library Services for Individuals with Limited English Proficiency. Fiscal Year 1987.

ERIC Educational Resources Information Center

Neff, Evaline B.

Libraries have played an important role in developing and operating programs which enhance English-language skills and ease assimilation into U.S. society. This report presents descriptions of the Library Services and Construction Act (LSCA) grants which funded library programs and projects benefitting individuals with limited English-speaking…

Directed evolution of the forkhead-associated domain to generate anti-phosphospecific reagents by phage-display

PubMed Central

Pershad, Kritika; Wypisniak, Karolina; Kay, Brian K.

2012-01-01

While affinity reagents are valuable tools for monitoring protein phosphorylation and studying signaling events in cells, generating them through immunization of animals with phosphopeptides is expensive, laborious and time consuming. An attractive alternative is to use protein evolution techniques and isolate new anti-phosphopeptide binding specificities from a library of variants of a phosphopeptide-binding domain. To explore this strategy, we attempted to display on the surface of bacteriophage M13, the N-terminal Forkhead-associated domain (FHA1) of yeast Rad53p, which is a naturally occurring phosphothreonine (pT)-binding domain, and found it to be non-functional due to misfolding in the bacterial periplasm. To overcome this limitation, a library of FHA1 variants was constructed by mutagenic PCR and functional variants were isolated after three rounds of affinity selection with its pT peptide ligand. A hydrophobic residue at position 34 in the β1-strand was discovered to be essential for phage-display of a functional FHA1 domain. Additionally, by heating the phage library to 50°C prior to affinity selection with its cognate pT peptide, we identified a variant (G2) that was ~8°C more thermal stable than the wild-type domain. Using G2 as a scaffold, we constructed phage-displayed libraries of FHA1 variants and affinity selected for variants that bound selectively to five pT peptides. These reagents are renewable and have high protein yields (~20–25 mg/L), when expressed in Escherichia coli. Thus, we have changed the specificity of the FHA1 domain and demonstrated that engineering phosphopeptide-binding domains is an attractive avenue for generating new anti-phosphopeptide binding specificities in vitro by phage-display. PMID:22985966

Directed evolution of the forkhead-associated domain to generate anti-phosphospecific reagents by phage display.

PubMed

Pershad, Kritika; Wypisniak, Karolina; Kay, Brian K

2012-11-23

While affinity reagents are valuable tools for monitoring protein phosphorylation and studying signaling events in cells, generating them through immunization of animals with phosphopeptides is expensive, laborious, and time-consuming. An attractive alternative is to use protein evolution techniques and isolate new anti-phosphopeptide binding specificities from a library of variants of a phosphopeptide-binding domain. To explore this strategy, we attempted to display on the surface of bacteriophage M13 the N-terminal Forkhead-associated (FHA1) domain of yeast Rad53p, which is a naturally occurring phosphothreonine (pT)-binding domain, and found it to be nonfunctional due to misfolding in the bacterial periplasm. To overcome this limitation, we constructed a library of FHA1 variants by mutagenic PCR and isolated functional variants after three rounds of affinity selection with its pT peptide ligand. A hydrophobic residue at position 34 in the β1 strand was discovered to be essential for phage display of a functional FHA1 domain. Additionally, by heating the phage library to 50°C prior to affinity selection with its cognate pT peptide, we identified a variant (G2) that was ~8°C more thermally stable than the wild-type domain. Using G2 as a scaffold, we constructed phage-displayed libraries of FHA1 variants and affinity selected for variants that bound selectively to five pT peptides. These reagents are renewable and have high protein yields (~20-25mg/L), when expressed in Escherichia coli. Thus, we have changed the specificity of the FHA1 domain and demonstrated that engineering phosphopeptide-binding domains is an attractive avenue for generating new anti-phosphopeptide binding specificities in vitro by phage display. Copyright © 2012 Elsevier Ltd. All rights reserved.

Construction of cDNA library from intestine, mesentery and coelomocyte of Apostichopus japonicus Selenka infected with Vibrio sp. and a preliminary analysis of immunity-related genes

NASA Astrophysics Data System (ADS)

Liu, Hongzhan; Zheng, Fengrong; Sun, Xiuqin; Cai, Yimei

2012-06-01

The aquaculture of sea cucumber Apostichopus japonicus (Echinodermata, Holothuroidea) has grown rapidly during recent years and has become an important sector of the marine industry in Northern China. However, with the rapid growth of the industry and the use of non-standard culture techniques, epidemic diseases of A. japonicus now pose increasing problems to the industry. To screen the genes with stress response to bacterial infection in sea cucumber at a genome wide level, we constructed a cDNA library from A. japonicus Selenka (Aspidochirotida: Stichopodidae) after infecting them with Vibrio sp. for 48 h. Total RNA was extracted from the intestine, mesentery and coelomocyte of infected sea cucumber using Trizol and mRNA was isolated by Oligotex mRNA Kits. The ligated cDNAs were transformed into DH5α, and a library of 3.24×105 clones (3.24×105 cfu mL-1) was obtained with the sizes of inserted fragments ranging from 0.8 to 2.5 kb. Sequencing the cDNA clones resulted in a total of 1106 ESTs that passed the quality control. BlastX and BlastN searches have identified 168 (31.5%) ESTs sharing significant homology with known sequences in NCBI protein or nucleotide databases. Among a panel of 25 putative immunity-related genes, serum lectin isoform, complement component 3, complement component 3-like genes were further studied by real-time PCR and they all increased more than 5 fold in response to Vibrio sp. challenge. Our library provides a valuable molecular tool for future study of invertebrate immunity against bacterial infection and our gene expression data indicates the importance of the immune system in the evolution and development of sea cucumber.

Rapid isolation of IgNAR variable single-domain antibody fragments from a shark synthetic library.

PubMed

Shao, Cui-Ying; Secombes, Chris J; Porter, Andrew J

2007-01-01

The immunoglobulin isotype IgNAR (Novel Antigen Receptor) was discovered in the serum of the nurse shark (Ginglymostoma cirratum) and wobbegong shark (Orectolobus maculates) as a homodimer of two protein chains, each composed of a single variable domain (V) domain and five constant domains. The IgNAR variable domain contains an intact antigen-binding site and functions as an independent domain able to react to antigen with both high specificity and affinity. Here we describe the successful construction of a synthetic phage-displayed library based upon a single anti-lysozyme clone HEL-5A7 scaffold, which was previously selected from an immune IgNAR variable domain library. The complementarity-determining region 3 (CDR3) loop of this clone was varied in both length and composition and the derived library was used to pan against two model proteins, lysozyme and leptin. A single anti-lysozyme clone (Ly-X20) and anti-leptin clone (Lep-12E1) were selected for further study. Both clones were shown to be functionally expressed in Escherichia coli, extremely thermostable and bind to corresponding antigens specifically. The results here demonstrate that a synthetic IgNAR variable domain library based on a single framework scaffold can be used as a route to generate antigen binders quickly, easily and without the need of immunization.

Sequence-based screening for self-sufficient P450 monooxygenase from a metagenome library.

PubMed

Kim, B S; Kim, S Y; Park, J; Park, W; Hwang, K Y; Yoon, Y J; Oh, W K; Kim, B Y; Ahn, J S

2007-05-01

Cytochrome P450 monooxygenases (CYPs) are useful catalysts for oxidation reactions. Self-sufficient CYPs harbour a reductive domain covalently connected to a P450 domain and are known for their robust catalytic activity with great potential as biocatalysts. In an effort to expand genetic sources of self-sufficient CYPs, we devised a sequence-based screening system to identify them in a soil metagenome. We constructed a soil metagenome library and performed sequence-based screening for self-sufficient CYP genes. A new CYP gene, syk181, was identified from the metagenome library. Phylogenetic analysis revealed that SYK181 formed a distinct phylogenic line with 46% amino-acid-sequence identity to CYP102A1 which has been extensively studied as a fatty acid hydroxylase. The heterologously expressed SYK181 showed significant hydroxylase activity towards naphthalene and phenanthrene as well as towards fatty acids. Sequence-based screening of metagenome libraries is expected to be a useful approach for searching self-sufficient CYP genes. The translated product of syk181 shows self-sufficient hydroxylase activity towards fatty acids and aromatic compounds. SYK181 is the first self-sufficient CYP obtained directly from a metagenome library. The genetic and biochemical information on SYK181 are expected to be helpful for engineering self-sufficient CYPs with broader catalytic activities towards various substrates, which would be useful for bioconversion of natural products and biodegradation of organic chemicals.

Construction of a genomic DNA library with a TA vector and its application in cloning of the phytoene synthase gene from the cyanobacterium Spirulina platensis M-135

NASA Astrophysics Data System (ADS)

Yoshikazu, Kawata; Shin-Ichi, Yano; Hiroyuki, Kojima

1998-03-01

An efficient and simple method for constructing a genomic DNA library using a TA cloning vector is presented. It is based on the sonicative cleavage of genomic DNA and modification of fragment ends with Taq DNA polymerase, followed by ligation using a TA vector. This method was applied for cloning of the phytoene synthase gene crt B from Spirulina platensis. This method is useful when genomic DNA cannot be efficiently digested with restriction enzymes, a problem often encountered during the construction of a genomic DNA library of cyanobacteria.

Library Resources for Bac End Sequencing. Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pieter J. de Jong

2000-10-01

Studies directed towards the specific aims outlined for this research award are summarized. The RPCI II Human Bac Library has been expanded by the addition of 6.9-fold genomic coverage. This segment has been generated from a MBOI partial digest of the same anonymous donor DNA used for the rest of the library. A new cloning vector, pTARBAC1, has been constructed and used in the construction of RPCI-II segment 5. This new cloning vector provides a new strategy in identifying targeted genomic regions and will greatly facilitate a large-scale analysis for positional cloning. A new maleCS7BC/6J mouse BAC library has beenmore » constructed. RPCI-23 contain 576 plates (approx 210,000 clones) and represents approximately 11-fold coverage of the mouse genome.« less

A pair of new BAC and BIBAC vectors that facilitate BAC/BIBAC library construction and intact large genomic DNA insert exchange.

PubMed

Shi, Xue; Zeng, Haiyang; Xue, Yadong; Luo, Meizhong

2011-10-11

Large-insert BAC and BIBAC libraries are important tools for structural and functional genomics studies of eukaryotic genomes. To facilitate the construction of BAC and BIBAC libraries and the transfer of complete large BAC inserts into BIBAC vectors, which is desired in positional cloning, we developed a pair of new BAC and BIBAC vectors. The new BAC vector pIndigoBAC536-S and the new BIBAC vector BIBAC-S have the following features: 1) both contain two 18-bp non-palindromic I-SceI sites in an inverted orientation at positions that flank an identical DNA fragment containing the lacZ selection marker and the cloning site. Large DNA inserts can be excised from the vectors as single fragments by cutting with I-SceI, allowing the inserts to be easily sized. More importantly, because the two vectors contain different antibiotic resistance genes for transformant selection and produce the same non-complementary 3' protruding ATAA ends by I-SceI that suppress self- and inter-ligations, the exchange of intact large genomic DNA inserts between the BAC and BIBAC vectors is straightforward; 2) both were constructed as high-copy composite vectors. Reliable linearized and dephosphorylated original low-copy pIndigoBAC536-S and BIBAC-S vectors that are ready for library construction can be prepared from the high-copy composite vectors pHZAUBAC1 and pHZAUBIBAC1, respectively, without the need for additional preparation steps or special reagents, thus simplifying the construction of BAC and BIBAC libraries. BIBAC clones constructed with the new BIBAC-S vector are stable in both E. coli and Agrobacterium. The vectors can be accessed through our website http://GResource.hzau.edu.cn. The two new vectors and their respective high-copy composite vectors can largely facilitate the construction and characterization of BAC and BIBAC libraries. The transfer of complete large genomic DNA inserts from one vector to the other is made straightforward.

Improvements to the Kunkel mutagenesis protocol for constructing primary and secondary phage-display libraries.

PubMed

Huang, Renhua; Fang, Pete; Kay, Brian K

2012-09-01

Site-directed mutagenesis is routinely performed in protein engineering experiments. One method, termed Kunkel mutagenesis, is frequently used for constructing libraries of peptide or protein variants in M13 bacteriophage, followed by affinity selection of phage particles. To make this method more efficient, the following two modifications were introduced: culture was incubated at 25°C for phage replication, which yielded two- to sevenfold more single-stranded DNA template compared to growth at 37°C, and restriction endonuclease recognition sites were used to remove non-recombinants. With both of the improvements, we could construct primary libraries of high complexity and that were 99-100% recombinant. Finally, with a third modification to the standard protocol of Kunkel mutagenesis, two secondary (mutagenic) libraries of a fibronectin type III (FN3) monobody were constructed with DNA segments that were amplified by error-prone and asymmetric PCR. Two advantages of this modification are that it bypasses the lengthy steps of restriction enzyme digestion and ligation, and that the pool of phage clones, recovered after affinity selection, can be used directly to generate a secondary library. Screening one of the two mutagenic libraries yielded variants that bound two- to fourfold tighter to human Pak1 kinase than the starting clone. The protocols described in this study should accelerate the discovery of phage-displayed recombinant affinity reagents. Copyright © 2012 Elsevier Inc. All rights reserved.

A platform for rapid prototyping of synthetic gene networks in mammalian cells

PubMed Central

Duportet, Xavier; Wroblewska, Liliana; Guye, Patrick; Li, Yinqing; Eyquem, Justin; Rieders, Julianne; Rimchala, Tharathorn; Batt, Gregory; Weiss, Ron

2014-01-01

Mammalian synthetic biology may provide novel therapeutic strategies, help decipher new paths for drug discovery and facilitate synthesis of valuable molecules. Yet, our capacity to genetically program cells is currently hampered by the lack of efficient approaches to streamline the design, construction and screening of synthetic gene networks. To address this problem, here we present a framework for modular and combinatorial assembly of functional (multi)gene expression vectors and their efficient and specific targeted integration into a well-defined chromosomal context in mammalian cells. We demonstrate the potential of this framework by assembling and integrating different functional mammalian regulatory networks including the largest gene circuit built and chromosomally integrated to date (6 transcription units, 27kb) encoding an inducible memory device. Using a library of 18 different circuits as a proof of concept, we also demonstrate that our method enables one-pot/single-flask chromosomal integration and screening of circuit libraries. This rapid and powerful prototyping platform is well suited for comparative studies of genetic regulatory elements, genes and multi-gene circuits as well as facile development of libraries of isogenic engineered cell lines. PMID:25378321

[Primary culture of cat intestinal epithelial cell and construction of its cDNA library].

PubMed

Ye, L; Gui-Hua, Z; Kun, Y; Hong-Fa, W; Ting, X; Gong-Zhen, L; Wei-Xia, Z; Yong, C

2017-04-12

Objective To establish the primary cat intestinal epithelial cells (IECs) culture methods and construct the cDNA library for the following yeast two-hybrid experiment, so as to screen the virulence interaction factors among the final host. Methods The primary cat IECs were cultured by the tissue cultivation and combined digestion with collagenase XI and dispase I separately. Then the cat IECs cultured was identified with the morphological observation and cyto-keratin detection, by using goat anti-cyto-keratin monoclonal antibodies. The mRNA of cat IECs was isolated and used as the template to synthesize the first strand cDNA by SMART™ technology, and then the double-strand cDNAs were acquired by LD-PCR, which were subsequently cloned into the plasmid PGADT7-Rec to construct yeast two-hybrid cDNA library in the yeast strain Y187 by homologous recombination. Matchmaker™ Insert Check PCR was used to detect the size distribution of cDNA fragments after the capacity calculation of the cDNA library. Results The comparison of the two cultivation methods indicated that the combined digestion of collagenase XI and dispase I was more effective than the tissue cultivation. The cat IECs system of continuous culture was established and the cat IECs with high purity were harvested for constructing the yeast two-hybrid cDNA library. The library contained 1.1×10 6 independent clones. The titer was 2.8×10 9 cfu/ml. The size of inserted fragments was among 0.5-2.0 kb. Conclusion The yeast two-hybrid cDNA library of cat IECs meets the requirements of further screen research, and this study lays the foundation of screening the Toxoplasma gondii virulence interaction factors among the cDNA libraries of its final hosts.

A Plan for Library Cooperation in Vermont, Report to the Vermont Free Public Library Service.

ERIC Educational Resources Information Center

Little (Arthur D.), Inc., Cambridge, MA.

A survey of library service in Vermont, financed with Library Services and Construction Act funds, was conducted in two parts: (1) an examination of the procedures used by the Free Public Library Service in its role as the focus of interlibrary cooperation in Vermont and an evaluation of library resources in the state and (2) an evaluation of…

Errors in CGAP xProfiler and cDNA DGED: the importance of library parsing and gene selection algorithms.

PubMed

Milnthorpe, Andrew T; Soloviev, Mikhail

2011-04-15

The Cancer Genome Anatomy Project (CGAP) xProfiler and cDNA Digital Gene Expression Displayer (DGED) have been made available to the scientific community over a decade ago and since then were used widely to find genes which are differentially expressed between cancer and normal tissues. The tissue types are usually chosen according to the ontology hierarchy developed by NCBI. The xProfiler uses an internally available flat file database to determine the presence or absence of genes in the chosen libraries, while cDNA DGED uses the publicly available UniGene Expression and Gene relational databases to count the sequences found for each gene in the presented libraries. We discovered that the CGAP approach often includes libraries from dependent or irrelevant tissues (one third of libraries were incorrect on average, with some tissue searches no correct libraries being selected at all). We also discovered that the CGAP approach reported genes from outside the selected libraries and may omit genes found within the libraries. Other errors include the incorrect estimation of the significance values and inaccurate settings for the library size cut-off values. We advocated a revised approach to finding libraries associated with tissues. In doing so, libraries from dependent or irrelevant tissues do not get included in the final library pool. We also revised the method for determining the presence or absence of a gene by searching the UniGene relational database, revised calculation of statistical significance and sorted the library cut-off filter. Our results justify re-evaluation of all previously reported results where NCBI CGAP expression data and tools were used.

Errors in CGAP xProfiler and cDNA DGED: the importance of library parsing and gene selection algorithms

PubMed Central

2011-01-01

Background The Cancer Genome Anatomy Project (CGAP) xProfiler and cDNA Digital Gene Expression Displayer (DGED) have been made available to the scientific community over a decade ago and since then were used widely to find genes which are differentially expressed between cancer and normal tissues. The tissue types are usually chosen according to the ontology hierarchy developed by NCBI. The xProfiler uses an internally available flat file database to determine the presence or absence of genes in the chosen libraries, while cDNA DGED uses the publicly available UniGene Expression and Gene relational databases to count the sequences found for each gene in the presented libraries. Results We discovered that the CGAP approach often includes libraries from dependent or irrelevant tissues (one third of libraries were incorrect on average, with some tissue searches no correct libraries being selected at all). We also discovered that the CGAP approach reported genes from outside the selected libraries and may omit genes found within the libraries. Other errors include the incorrect estimation of the significance values and inaccurate settings for the library size cut-off values. We advocated a revised approach to finding libraries associated with tissues. In doing so, libraries from dependent or irrelevant tissues do not get included in the final library pool. We also revised the method for determining the presence or absence of a gene by searching the UniGene relational database, revised calculation of statistical significance and sorted the library cut-off filter. Conclusion Our results justify re-evaluation of all previously reported results where NCBI CGAP expression data and tools were used. PMID:21496233

A plasmid toolkit for cloning chimeric cDNAs encoding customized fusion proteins into any Gateway destination expression vector

PubMed Central

2013-01-01

Background Valuable clone collections encoding the complete ORFeomes for some model organisms have been constructed following the completion of their genome sequencing projects. These libraries are based on Gateway cloning technology, which facilitates the study of protein function by simplifying the subcloning of open reading frames (ORF) into any suitable destination vector. The expression of proteins of interest as fusions with functional modules is a frequent approach in their initial functional characterization. A limited number of Gateway destination expression vectors allow the construction of fusion proteins from ORFeome-derived sequences, but they are restricted to the possibilities offered by their inbuilt functional modules and their pre-defined model organism-specificity. Thus, the availability of cloning systems that overcome these limitations would be highly advantageous. Results We present a versatile cloning toolkit for constructing fully-customizable three-part fusion proteins based on the MultiSite Gateway cloning system. The fusion protein components are encoded in the three plasmids integral to the kit. These can recombine with any purposely-engineered destination vector that uses a heterologous promoter external to the Gateway cassette, leading to the in-frame cloning of an ORF of interest flanked by two functional modules. In contrast to previous systems, a third part becomes available for peptide-encoding as it no longer needs to contain a promoter, resulting in an increased number of possible fusion combinations. We have constructed the kit’s component plasmids and demonstrate its functionality by providing proof-of-principle data on the expression of prototype fluorescent fusions in transiently-transfected cells. Conclusions We have developed a toolkit for creating fusion proteins with customized N- and C-term modules from Gateway entry clones encoding ORFs of interest. Importantly, our method allows entry clones obtained from ORFeome collections to be used without prior modifications. Using this technology, any existing Gateway destination expression vector with its model-specific properties could be easily adapted for expressing fusion proteins. PMID:23957834

A plasmid toolkit for cloning chimeric cDNAs encoding customized fusion proteins into any Gateway destination expression vector.

PubMed

Buj, Raquel; Iglesias, Noa; Planas, Anna M; Santalucía, Tomàs

2013-08-20

Valuable clone collections encoding the complete ORFeomes for some model organisms have been constructed following the completion of their genome sequencing projects. These libraries are based on Gateway cloning technology, which facilitates the study of protein function by simplifying the subcloning of open reading frames (ORF) into any suitable destination vector. The expression of proteins of interest as fusions with functional modules is a frequent approach in their initial functional characterization. A limited number of Gateway destination expression vectors allow the construction of fusion proteins from ORFeome-derived sequences, but they are restricted to the possibilities offered by their inbuilt functional modules and their pre-defined model organism-specificity. Thus, the availability of cloning systems that overcome these limitations would be highly advantageous. We present a versatile cloning toolkit for constructing fully-customizable three-part fusion proteins based on the MultiSite Gateway cloning system. The fusion protein components are encoded in the three plasmids integral to the kit. These can recombine with any purposely-engineered destination vector that uses a heterologous promoter external to the Gateway cassette, leading to the in-frame cloning of an ORF of interest flanked by two functional modules. In contrast to previous systems, a third part becomes available for peptide-encoding as it no longer needs to contain a promoter, resulting in an increased number of possible fusion combinations. We have constructed the kit's component plasmids and demonstrate its functionality by providing proof-of-principle data on the expression of prototype fluorescent fusions in transiently-transfected cells. We have developed a toolkit for creating fusion proteins with customized N- and C-term modules from Gateway entry clones encoding ORFs of interest. Importantly, our method allows entry clones obtained from ORFeome collections to be used without prior modifications. Using this technology, any existing Gateway destination expression vector with its model-specific properties could be easily adapted for expressing fusion proteins.

Feasibility of physical map construction from fingerprinted bacterial artificial chromosome libraries of polyploid plant species

PubMed Central

2010-01-01

Background The presence of closely related genomes in polyploid species makes the assembly of total genomic sequence from shotgun sequence reads produced by the current sequencing platforms exceedingly difficult, if not impossible. Genomes of polyploid species could be sequenced following the ordered-clone sequencing approach employing contigs of bacterial artificial chromosome (BAC) clones and BAC-based physical maps. Although BAC contigs can currently be constructed for virtually any diploid organism with the SNaPshot high-information-content-fingerprinting (HICF) technology, it is currently unknown if this is also true for polyploid species. It is possible that BAC clones from orthologous regions of homoeologous chromosomes would share numerous restriction fragments and be therefore included into common contigs. Because of this and other concerns, physical mapping utilizing the SNaPshot HICF of BAC libraries of polyploid species has not been pursued and the possibility of doing so has not been assessed. The sole exception has been in common wheat, an allohexaploid in which it is possible to construct single-chromosome or single-chromosome-arm BAC libraries from DNA of flow-sorted chromosomes and bypass the obstacles created by polyploidy. Results The potential of the SNaPshot HICF technology for physical mapping of polyploid plants utilizing global BAC libraries was evaluated by assembling contigs of fingerprinted clones in an in silico merged BAC library composed of single-chromosome libraries of two wheat homoeologous chromosome arms, 3AS and 3DS, and complete chromosome 3B. Because the chromosome arm origin of each clone was known, it was possible to estimate the fidelity of contig assembly. On average 97.78% or more clones, depending on the library, were from a single chromosome arm. A large portion of the remaining clones was shown to be library contamination from other chromosomes, a feature that is unavoidable during the construction of single-chromosome BAC libraries. Conclusions The negligibly low level of incorporation of clones from homoeologous chromosome arms into a contig during contig assembly suggested that it is feasible to construct contigs and physical maps using global BAC libraries of wheat and almost certainly also of other plant polyploid species with genome sizes comparable to that of wheat. Because of the high purity of the resulting assembled contigs, they can be directly used for genome sequencing. It is currently unknown but possible that equally good BAC contigs can be also constructed for polyploid species containing smaller, more gene-rich genomes. PMID:20170511

Planning for a New Generation of Public Library Buildings. The Greenwood Library Management Collection.

ERIC Educational Resources Information Center

McCabe, Gerard B.

This book on public library design and construction contains the following chapters: (1) "Beginning the Plan"; (2) "Data for Planning"; (3) "Location: Finding a Site"; (4) "Interior Design"; (5) "Furnishing and Equipping the Library and Its Environs"; (6) "Other Views," including "Using Small College Library Planning Techniques in Public Library…

The Alabama Long Range Program for Library Development, 1995-1999.

ERIC Educational Resources Information Center

Alabama Public Library Service, Montgomery.

This document contains the long range plan of the Alabama public libraries. The purpose of presenting this long range program is to meet the requirements of the Library Services and Construction Act (LSCA) and to assess, prioritize, and communicate library needs to librarians, officials, and the public to provide adequate library service to the…

The Alabama Long Range Program for Library Development 1994-1998.

ERIC Educational Resources Information Center

Alabama Public Library Service, Montgomery.

This document contains the long range plan of the Alabama public libraries. The purpose of presenting this program is to meet the requirements of the Library Services and Construction Act (LSCA) and to assess, prioritize, and communicate library needs to librarians, officials, and the public to provide adequate library service to the citizens of…

Tapping Teen Talent in Queens: A Library-Based, LSCA-Funded Youth Development Success Story from New York.

ERIC Educational Resources Information Center

Williams, Barbara Osborne

1996-01-01

Describes a program developed by the Youth Services Division at the Queens Borough Public Library's Central Library to help teenagers maximize growth opportunities, build self-esteem, and see the library as a life resource. Highlights include securing funding through LSCA (Library Services and Construction Act), recruiting participants, and…

Carver County Library System, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Colhapp, Barbara; Miller, Lana

The Carver County Library System (Chaska, Minnesota) conducted a project to demonstrate adult educational teamwork between libraries and literacy agents in the Carver-Scott two county area. The project, "National Issues Forums (NIF) for the New Reader," extended educational opportunities that encouraged new adult readers and the public…

The development and characterisation of a bacterial artificial chromosome library for Fragaria vesca

PubMed Central

Bonet, Julio; Girona, Elena Lopez; Sargent, Daniel J; Muñoz-Torres, Monica C; Monfort, Amparo; Abbott, Albert G; Arús, Pere; Simpson, David W; Davik, Jahn

2009-01-01

Background The cultivated strawberry Fragaria ×ananassa is one of the most economically-important soft-fruit species. Few structural genomic resources have been reported for Fragaria and there exists an urgent need for the development of physical mapping resources for the genus. The first stage in the development of a physical map for Fragaria is the construction and characterisation of a high molecular weight bacterial artificial chromosome (BAC) library. Methods A BAC library, consisting of 18,432 clones was constructed from Fragaria vesca f. semperflorens accession 'Ali Baba'. BAC DNA from individual library clones was pooled to create a PCR-based screening assay for the library, whereby individual clones could be identified with just 34 PCR reactions. These pools were used to screen the BAC library and anchor individual clones to the diploid Fragaria reference map (FV×FN). Findings Clones from the BAC library developed contained an average insert size of 85 kb, representing over seven genome equivalents. The pools and superpools developed were used to identify a set of BAC clones containing 70 molecular markers previously mapped to the diploid Fragaria FV×FN reference map. The number of positive colonies identified for each marker suggests the library represents between 4× and 10× coverage of the diploid Fragaria genome, which is in accordance with the estimate of library coverage based on average insert size. Conclusion This BAC library will be used for the construction of a physical map for F. vesca and the superpools will permit physical anchoring of molecular markers using PCR. PMID:19772672

Molecular analysis of the biological bleaching of kraft pulps by Trametes versicolor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dumonceaux, T.J.; Archibald, F.S.

1996-10-01

Biological bleaching of kraft pulps by the fungus Trametes versicolor, based on the biodegradation of the recalcitrant polymer, lignin, could replace chlorine-based bleaching in Canadian pulp and paper mills. Enzymes that may be involved in lignin degradation include manganese peroxidase (MnP), laccase, and cellobiose-quinone oxidoreductase (CBQase). All three of these enzymatic activities are thought to interact extensively in cyclic oxidation/reduction reactions which ultimately bring about the degradation of lignin. We have constructed a cDNA library from T versicolor with the aim of isolating clones encoding factors that are relevant to biobleaching. We first determined the optimum growth conditions for expressionmore » of bleaching-related mRNA. A clear induction of bleaching ability was observed when the fungus was preincubated with 0.25% acid-washed pulp; the augmentation of bleaching was not explained by differences in MnP or laccase levels, suggesting that the expression of either CBQase or unidentified biobleaching factors was responsible for the increased pulp brightness. mRNA isolated from induced cultures was used to construct a cDNA library in a XZAP vector. This library has been probed with a degenerate oligonucleotide probe based upon a peptide sequence derived from purified CBQase, resulting in the identification of several hybridizing cDNA molecules. The CBQase clone will be used to examine in further detail the potential role of this enzyme in pulp biobleaching and lignin degradation.« less

Keeping a Dream Alive: Cooper Union Library.

ERIC Educational Resources Information Center

Iwan, Irene

1984-01-01

Profiles the Cooper Union Library, a private academic library specializing in architecture, art, and engineering that celebrated its 125th anniversary in fall 1984. Highlights include a biographical sketch of the college's founder, Peter Cooper; construction of the building; curriculum changes; library services and materials; and cooperative and…

Libraries and Literacy in Ecological Perspective

ERIC Educational Resources Information Center

Sensenig, Victor J.

2012-01-01

This study investigated the nature of the literacy environment that public libraries construct and how they share the project of children's literacy development with homes and schools. It focuses on library programs for children, particularly story times. Its data came from observations of library activities, interviews with librarians and…

Construction of Rabbit Immune Antibody Libraries.

PubMed

Nguyen, Thi Thu Ha; Lee, Jong Seo; Shim, Hyunbo

2018-01-01

Rabbits have distinct advantages over mice as a source of target-specific antibodies. They produce higher affinity antibodies than mice, and may elicit strong immune response against antigens or epitopes that are poorly immunogenic or tolerated in mice. However, a great majority of currently available monoclonal antibodies are of murine origin because of the wider availability of murine fusion partner cell lines and well-established tools and protocols for fusion and cloning of mouse hybridoma. Phage-display selection of antibody libraries is an alternative method to hybridoma technology for the generation of target-specific monoclonal antibodies. High-affinity monoclonal antibodies from nonmurine species can readily be obtained by constructing immune antibody libraries from B cells of the immunized animal and screening the library by phage display. In this article, we describe the construction of a rabbit immune Fab library for the facile isolation of rabbit monoclonal antibodies. After immunization, B-cell cDNA is obtained from the spleen of the animal, from which antibody variable domain repertoires are amplified and assembled into a Fab repertoire by PCR. The Fab genes are then cloned into a phagemid vector and transformed to E. coli, from which a phage-displayed immune Fab library is rescued. Such a library can be biopanned against the immunization antigen for rapid identification of high-affinity, target-specific rabbit monoclonal antibodies.

Scaffolds for Artificial miRNA Expression in Animal Cells.

PubMed

Calloni, Raquel; Bonatto, Diego

2015-10-01

Artificial miRNAs (amiRNAs) are molecules that have been developed to promote gene silencing in a similar manner to naturally occurring miRNAs. amiRNAs are generally constructed by replacing the mature miRNA sequence in the pre-miRNA stem-loop with a sequence targeting a gene of interest. These molecules offer an interesting alternative to silencing approaches that are based on shRNAs and siRNAs because they present the same efficiency as these options and are less cytotoxic. amiRNAs have mostly been applied to gene knockdown in plants; they have been examined to a lesser extent in animal cells. Therefore, this article reviews the amiRNAs that have been developed for animal cells and focuses on the miRNA scaffolds that can already be applied to construct the artificial counterparts, as well as on the different approaches that have been described to promote amiRNA expression and silencing efficiency. Furthermore, the availability of amiRNA libraries and other tools that can be used to design and construct these molecules is briefly discussed, along with an overview of the therapeutic applications for which amiRNAs have already been evaluated.

Transcriptome Characterization Analysis of Bactrocera minax and New Insights into Its Pupal Diapause Development with Gene Expression Analysis

PubMed Central

Dong, Yongcheng; Desneux, Nicolas; Lei, Chaoliang; Niu, Changying

2014-01-01

Bactrocera minax is a major citrus pest distributed in China, Bhutan and India. The long pupal diapause duration of this fly is a major bottleneck for artificial rearing and underlying mechanisms remain unknown. Genetic information on B. minax transcriptome and gene expression profiles are needed to understand its pupal diapause. High-throughput RNA-seq technology was used to characterize the B. minax transcriptome and to identify differentially expressed genes during pupal diapause development. A total number of 52,519,948 reads were generated and assembled into 47,217 unigenes. 26,843 unigenes matched to proteins in the NCBI database using the BLAST search. Four digital gene expression (DGE) libraries were constructed for pupae at early diapause, late diapause, post-diapause and diapause terminated developmental status. 4,355 unigenes showing the differences expressed across four libraries revealed major shifts in cellular functions of cell proliferation, protein processing and export, metabolism and stress response in pupal diapause. When diapause was terminated by 20-hydroxyecdysone (20E), many genes involved in ribosome and metabolism were differentially expressed which may mediate diapause transition. The gene sets involved in protein and energy metabolisms varied throughout early-, late- and post-diapause. A total of 15 genes were selected to verify the DGE results through quantitative real-time PCR (qRT-PCR); qRT-PCR expression levels strongly correlated with the DGE data. The results provided the extensive sequence resources available for B. minax and increased our knowledge on its pupal diapause development and they shed new light on the possible mechanisms involved in pupal diapause in this species. PMID:25285037

International Reports.

ERIC Educational Resources Information Center

Anderson, Nancy D.; And Others

1994-01-01

Three reports discuss the International Federation of Library Associations and Institutions; the Frankfurt Book Fair, focusing on electronics; and Canadian library trends, including resource sharing, technology projects, information policy, censorship, services for persons with disabilities, construction projects, and library education and…

Construction of a 3D-shaped, natural product like fragment library by fragmentation and diversification of natural products.

PubMed

Prescher, Horst; Koch, Guido; Schuhmann, Tim; Ertl, Peter; Bussenault, Alex; Glick, Meir; Dix, Ina; Petersen, Frank; Lizos, Dimitrios E

2017-02-01

A fragment library consisting of 3D-shaped, natural product-like fragments was assembled. Library construction was mainly performed by natural product degradation and natural product diversification reactions and was complemented by the identification of 3D-shaped, natural product like fragments available from commercial sources. In addition, during the course of these studies, novel rearrangements were discovered for Massarigenin C and Cytochalasin E. The obtained fragment library has an excellent 3D-shape and natural product likeness, covering a novel, unexplored and underrepresented chemical space in fragment based drug discovery (FBDD). Copyright © 2016 Elsevier Ltd. All rights reserved.

Building a Library Network from Scratch: Eric & Veronica's Excellent Adventure.

ERIC Educational Resources Information Center

Sisler, Eric; Smith, Veronica

2000-01-01

Describes library automation issues during the planning and construction of College Hill Library (Colorado), a joint-use facility shared by a community college and a public library. Discuses computer networks; hardware selection; public access to catalogs and electronic resources; classification schemes and bibliographic data; children's…

Meriden Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

MacCabe, Bruce

The Literacy Learning Center Project, a project of the Meriden Public Library (Connecticut), targeted the educationally underserved and functionally illiterate, and involved recruitment, retention, space renovation, coalition building, public awareness, training, basic literacy, collection development, tutoring, computer assisted services, and…

Construction and application of a functional library of cytochrome P450 monooxygenases from the filamentous fungus Aspergillus oryzae.

PubMed

Nazir, K H M Nazmul Hussain; Ichinose, Hirofumi; Wariishi, Hiroyuki

2011-05-01

A functional library of cytochrome P450 monooxygenases from Aspergillus oryzae (AoCYPs) was constructed in which 121 isoforms were coexpressed with yeast NADPH-cytochrome P450 oxidoreductase in Saccharomyces cerevisiae. Using this functional library, novel catalytic functions of AoCYPs, such as catalytic potentials of CYP57B3 against genistein, were elucidated for the first time. Comprehensive functional screening promises rapid characterization of catalytic potentials and utility of AoCYPs.

Library of Congress Mass Book Deacidification Facility. Hearing before the Committee on Rules and Administration, United States Senate, Ninety-Eighth Congress, Second Session, on S. 2418, Providing for the Library of Congress Mass Book Deacidification Facility.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Senate Committee on Rules and Administration.

This document presents testimony heard on S. 2418, a bill to authorize the Librarian of Congress to construct the Library of Congress Mass Book Deacidification Facility at Fort Detrick, near Frederick, Maryland, subject to the supervision and construction authority of a federal, civilian, or military agency. The facility would be used to…

The proteins interacting with C-terminal of μ receptor are identified by bacterial two-hybrid system from brain cDNA library in morphine-dependent rats.

PubMed

Zhou, Peilan; Jiang, Jiebing; Dong, Zhaoqi; Yan, Hui; You, Zhendong; Su, Ruibin; Gong, Zehui

2015-12-15

Opioid addiction is associated with long-term adaptive changes in the brain that involve protein expression. The carboxyl-terminal of the μ opioid receptor (MOR-C) is important for receptor signal transduction under opioid treatment. However, the proteins that interact with MOR-C after chronic morphine exposure remain unknown. The brain cDNA library of chronic morphine treatment rats was screened using rat MOR-C to investigate the regulator of opioids dependence in the present study. The brain cDNA library from chronic morphine-dependent rats was constructed using the SMART (Switching Mechanism At 5' end of RNA Transcript) technique. Bacterial two-hybrid system was used to screening the rat MOR-C interacting proteins from the cDNA library. RT-qPCR and immunoblotting were used to determine the variation of MOR-C interacting proteins in rat brain after chronic morphine treatment. Column overlay assays, immunocytochemistry and coimmunoprecipitation were used to demonstrate the interaction of MOR-C and p75NTR-associated cell death executor (NADE). 21 positive proteins, including 19 known proteins were screened to interact with rat MOR-C. Expression of several of these proteins was altered in specific rat brain regions after chronic morphine treatment. Among these proteins, NADE was confirmed to interact with rat MOR-C by in vitro protein-protein binding and coimmunoprecipitation in Chinese hamster ovary (CHO) cells and rat brain with or without chronic morphine treatment. Understanding the rat MOR-C interacting proteins and the proteins variation under chronic morphine treatment may be critical for determining the pathophysiological basis of opioid tolerance and addiction. Copyright © 2015. Published by Elsevier Inc.

Differential gene expression profiles in the venom gland/sac of Eumenes pomiformis (Hymenoptera: Eumenidae).

PubMed

Baek, Ji Hyeong; Lee, Si Hyeock

2010-06-01

To search for novel transcripts encoding biologically active venom components, a subtractive cDNA library specific to the venom gland and sac (gland/sac) of a solitary hunting wasp species, Eumenes pomiformis Fabricius (1781), was constructed by suppression subtractive hybridization. A total of 541 expressed sequence tags (ESTs) were clustered and assembled into 102 contigs (31 multiple sequences and 71 singletons). In total, 37 cDNAs were found in the library via BLASTx searching and manual annotation. Eight contigs (337 ESTs) encoding short venom peptides (10 to 16 amino acids) occupied 62% of the library. The deduced amino acid sequence (78 amino acids) of a novel venom peptide transcript shared sequence similarity with trypsin inhibitors and dendrotoxin-like venom peptides known to be K(+) channel blockers, implying that this novel peptide may play a role in the paralysis of prey. In addition to phospholipase A2 and hyaluronidase, which are known to be the main components of wasp venoms, several transcripts encoding enzymes, including three metallopeptidases and a decarboxylase likely involved in the processing and activation of venomous proteins, peptides, amines, and neurotransmitters, were also isolated from the library. The presence of a transcript encoding a putative insulin/insulin-like peptide binding protein suggests that solitary hunting wasps use their venom to control their prey, leading to larval growth cessation. The abundance of these venom components in the venom gland/sac and in the alimentary canal was confirmed by quantitative real-time PCR. Discovery of venom gland/sac-specific transcripts should promote further studies on biologically active components in the venom of solitary hunting wasps. Copyright 2010 Elsevier Ltd. All rights reserved.

Library Law Handbook: State Laws Relating to Michigan Libraries. 1993 Edition.

ERIC Educational Resources Information Center

Michigan Library, Lansing.

This document is a compilation of state laws relating to Michigan libraries, intended as a tool for library managers and as an expression of continued commitment to strengthening library services throughout the state. It reprints legislation directly related to libraries of all levels, including: library networks; regional libraries: district…

Health sciences library building projects: 1995 survey.

PubMed Central

Ludwig, L

1996-01-01

The Medical Library Association's fifth annual survey of recent health sciences library building projects identified twenty-five libraries planning, expanding, or constructing new library facilities. None of the fifteen new library projects are free standing structures; however, several occupy a major portion of the project space. Ten projects involve renovation of or addition to existing space. Information regarding size, cost of project, type of construction, completion date, and other factual data was provided for twelve projects. The remaining identified projects are in pre-design or early-design stages, or are awaiting funding approval. Library building projects for three hospital libraries, three academic medical libraries, and an association library are described. Each illustrates how considerations of economics and technology are changing the traditional library model from a centrally stored information depository housing a wide range of information under one roof where users come to the information, into an electronic model gradually shifting from investment in the physical presence of resources to investment in creating work space for creditible information specialists who help in-house and distanced users to obtain information electronically from any place and at any time. This new model includes a highly skilled library team to manage, filter, and package the information to users trained by these resident experts. Images PMID:8883981

Health sciences library building projects: 1995 survey.

PubMed

Ludwig, L

1996-07-01

The Medical Library Association's fifth annual survey of recent health sciences library building projects identified twenty-five libraries planning, expanding, or constructing new library facilities. None of the fifteen new library projects are free standing structures; however, several occupy a major portion of the project space. Ten projects involve renovation of or addition to existing space. Information regarding size, cost of project, type of construction, completion date, and other factual data was provided for twelve projects. The remaining identified projects are in pre-design or early-design stages, or are awaiting funding approval. Library building projects for three hospital libraries, three academic medical libraries, and an association library are described. Each illustrates how considerations of economics and technology are changing the traditional library model from a centrally stored information depository housing a wide range of information under one roof where users come to the information, into an electronic model gradually shifting from investment in the physical presence of resources to investment in creating work space for creditible information specialists who help in-house and distanced users to obtain information electronically from any place and at any time. This new model includes a highly skilled library team to manage, filter, and package the information to users trained by these resident experts.

Extending Immunological Profiling in the Gilthead Sea Bream, Sparus aurata, by Enriched cDNA Library Analysis, Microarray Design and Initial Studies upon the Inflammatory Response to PAMPs.

PubMed

Boltaña, Sebastian; Castellana, Barbara; Goetz, Giles; Tort, Lluis; Teles, Mariana; Mulero, Victor; Novoa, Beatriz; Figueras, Antonio; Goetz, Frederick W; Gallardo-Escarate, Cristian; Planas, Josep V; Mackenzie, Simon

2017-02-03

This study describes the development and validation of an enriched oligonucleotide-microarray platform for Sparus aurata (SAQ) to provide a platform for transcriptomic studies in this species. A transcriptome database was constructed by assembly of gilthead sea bream sequences derived from public repositories of mRNA together with reads from a large collection of expressed sequence tags (EST) from two extensive targeted cDNA libraries characterizing mRNA transcripts regulated by both bacterial and viral challenge. The developed microarray was further validated by analysing monocyte/macrophage activation profiles after challenge with two Gram-negative bacterial pathogen-associated molecular patterns (PAMPs; lipopolysaccharide (LPS) and peptidoglycan (PGN)). Of the approximately 10,000 EST sequenced, we obtained a total of 6837 EST longer than 100 nt, with 3778 and 3059 EST obtained from the bacterial-primed and from the viral-primed cDNA libraries, respectively. Functional classification of contigs from the bacterial- and viral-primed cDNA libraries by Gene Ontology (GO) showed that the top five represented categories were equally represented in the two libraries: metabolism (approximately 24% of the total number of contigs), carrier proteins/membrane transport (approximately 15%), effectors/modulators and cell communication (approximately 11%), nucleoside, nucleotide and nucleic acid metabolism (approximately 7.5%) and intracellular transducers/signal transduction (approximately 5%). Transcriptome analyses using this enriched oligonucleotide platform identified differential shifts in the response to PGN and LPS in macrophage-like cells, highlighting responsive gene-cassettes tightly related to PAMP host recognition. As observed in other fish species, PGN is a powerful activator of the inflammatory response in S. aurata macrophage-like cells. We have developed and validated an oligonucleotide microarray (SAQ) that provides a platform enriched for the study of gene expression in S. aurata with an emphasis upon immunity and the immune response.

Transcriptome analysis of Ruditapes philippinarum hepatopancreas provides insights into immune signaling pathways under Vibrio anguillarum infection.

PubMed

Ren, Yipeng; Xue, Junli; Yang, Huanhuan; Pan, Baoping; Bu, Wenjun

2017-05-01

The Manila clam, Ruditapes philippinarum, is one of the most economically important aquatic clams that are harvested on a large scale by the mariculture industry in China. However, increasing reports of bacterial pathogenic diseases have had a negative effect on the aquaculture industry of R. philippinarum. In the present study, the two transcriptome libraries of untreated (termed H) and challenged Vibrio anguillarum (termed HV) hepatopancreas were constructed and sequenced from Manila clam using an Illumina-based paired-end sequencing platform. In total, 75,302,886 and 66,578,976 high-quality clean reads were assembled from 101,080,746 and 99,673,538 raw data points from the two transcriptome libraries described above, respectively. Furthermore, 156,116 unigenes were generated from 210,685 transcripts, with an N50 length of 1125 bp, and from the annotated SwissProt, NR, NT, KO, GO, KOG and KEGG databases. Moreover, a total of 4071 differentially expressed unigenes (HV vs H) were detected, including 903 up-regulated and 3168 down-regulated genes. Among these differentially expressed unigenes, 226 unigenes were annotated using KEGG annotation in 16 immune-related signaling pathways, including Toll-like receptor, NF-kappa B, MAPK, NOD-like receptor, RIG-I-like receptor, and the TNF and chemokine signaling pathways. Finally, 20,341 simple sequence repeats (SSRs) and 214,430 potential single nucleotide polymorphisms (SNPs) were detected from the H and HV transcriptome libraries. In conclusion, these studies identified many candidate immune-related genes and signaling pathways and conducted a comparative analysis of the differentially expressed unigenes from Manila clam hepatopancreas in response to V. anguillarum stimulation. These data laid the foundation for studying the innate immune systems and defense mechanisms in R. philippinarum. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chicken microsatellite markers isolated from libraries enriched for simple tandem repeats.

PubMed

Gibbs, M; Dawson, D A; McCamley, C; Wardle, A F; Armour, J A; Burke, T

1997-12-01

The total number of microsatellite loci is considered to be at least 10-fold lower in avian species than in mammalian species. Therefore, efficient large-scale cloning of chicken microsatellites, as required for the construction of a high-resolution linkage map, is facilitated by the construction of libraries using an enrichment strategy. In this study, a plasmid library enriched for tandem repeats was constructed from chicken genomic DNA by hybridization selection. Using this technique the proportion of recombinant clones that cross-hybridized to probes containing simple tandem repeats was raised to 16%, compared with < 0.1% in a non-enriched library. Primers were designed from 121 different sequences. Polymerase chain reaction (PCR) analysis of two chicken reference pedigrees enabled 72 loci to be localized within the collaborative chicken genetic map, and at least 30 of the remaining loci have been shown to be informative in these or other crosses.

Construction, database integration, and application of an Oenothera EST library.

PubMed

Mrácek, Jaroslav; Greiner, Stephan; Cho, Won Kyong; Rauwolf, Uwe; Braun, Martha; Umate, Pavan; Altstätter, Johannes; Stoppel, Rhea; Mlcochová, Lada; Silber, Martina V; Volz, Stefanie M; White, Sarah; Selmeier, Renate; Rudd, Stephen; Herrmann, Reinhold G; Meurer, Jörg

2006-09-01

Coevolution of cellular genetic compartments is a fundamental aspect in eukaryotic genome evolution that becomes apparent in serious developmental disturbances after interspecific organelle exchanges. The genus Oenothera represents a unique, at present the only available, resource to study the role of the compartmentalized plant genome in diversification of populations and speciation processes. An integrated approach involving cDNA cloning, EST sequencing, and bioinformatic data mining was chosen using Oenothera elata with the genetic constitution nuclear genome AA with plastome type I. The Gene Ontology system grouped 1621 unique gene products into 17 different functional categories. Application of arrays generated from a selected fraction of ESTs revealed significantly differing expression profiles among closely related Oenothera species possessing the potential to generate fertile and incompatible plastid/nuclear hybrids (hybrid bleaching). Furthermore, the EST library provides a valuable source of PCR-based polymorphic molecular markers that are instrumental for genotyping and molecular mapping approaches.

Phage selection of peptide "microantibodies".

PubMed

Fujiwara, Daisuke; Fujii, Ikuo

2013-01-01

A bioactive peptide capable of inhibiting protein-protein interactions has the potential to be a molecular tool for biological studies and a therapeutic by disrupting aberrant interactions involved in diseases. We have developed combinatorial libraries of peptides with helix-loop-helix structure, from which the isolated peptides have the constrained structure to reduce entropy costs in binding, resulting in high binding affinities for target molecules. Previously, we designed a de novo peptide of helix-loop-helix structure that we termed a "microantibody." Using the microantibody as a library scaffold, we have constructed a phage-display library to successfully isolate molecular-targeting peptides against a cytokine receptor (granulocyte colony-stimulating factor receptor), a protein kinase (Aurora-A), and a ganglioside (GM1). Protocols in this article describe a general procedure for the library construction and the library screening.

microRNAs and Their Targets in Apple (Malus domestica cv. "Fuji") Involved in Response to Infection of Pathogen Valsa mali.

PubMed

Feng, Hao; Xu, Ming; Zheng, Xiang; Zhu, Tongyi; Gao, Xiaoning; Huang, Lili

2017-01-01

miRNAs are important regulators involving in plant-pathogen interactions. However, their roles in apple tree response to Valsa canker pathogen ( Valsa mali, Vm ) infection were poorly understood. In this study, we constructed two miRNA libraries using the twig bark tissues of apple tree ( Malus domestica Borkh. cv. "Fuji") inoculated with Vm (IVm) and PDA medium (control, BMd). Among all detected miRNAs, 23 miRNAs were specifically isolated from BMd and 39 miRNAs were specifically isolated from IVm. Meanwhile, the expression of 294 miRNAs decreased; and another 172 miRNAs showed an increased expression trend in IVm compared with that in BMd. Furthermore, two degradome sequencing libraries were also constructed to identify the target genes of these miRNAs. In total, 353 differentially expressed miRNAs between IVm and BMd were detected to be able to target 1,077 unigenes with 2,251 cleavage sites. Based on GO and KEGG analysis, these genes were found to be mainly related to transcription regulation and signal transduction. In addition, we selected 17 miRNAs and 22 corresponding target genes to screen the expression profiles when apple twigs were infected by Vm . The expression trends of most miRNAs/target genes were consist with the results of deep sequencing. Many of them may involve in the apple twig- Vm interaction by inducing/reducing their expression. What's more, miRNAs and their target genes regulate the apple twig- Vm interaction by forming many complicated regulation networks rather than one to one model. It is worth that a conserved miRNAs mdm-miR482b, which was down regulated in IVm compared with BMd, has 14 potential target genes, most of which are disease resistance related genes. This indicates that mdm-miR482b may play important roles in apple twig response to Vm . More important, the feedback regulation of sRNA pathway in apple twig is also very complex, and play critical role in the interaction between apple twig and Vm based on the results of expression analysis. In all, the results will provide insights into the crucial functions of miRNAs in the woody plant, apple tree- Vm interaction.

microRNAs and Their Targets in Apple (Malus domestica cv. “Fuji”) Involved in Response to Infection of Pathogen Valsa mali

PubMed Central

Feng, Hao; Xu, Ming; Zheng, Xiang; Zhu, Tongyi; Gao, Xiaoning; Huang, Lili

2017-01-01

miRNAs are important regulators involving in plant-pathogen interactions. However, their roles in apple tree response to Valsa canker pathogen (Valsa mali, Vm) infection were poorly understood. In this study, we constructed two miRNA libraries using the twig bark tissues of apple tree (Malus domestica Borkh. cv. “Fuji”) inoculated with Vm (IVm) and PDA medium (control, BMd). Among all detected miRNAs, 23 miRNAs were specifically isolated from BMd and 39 miRNAs were specifically isolated from IVm. Meanwhile, the expression of 294 miRNAs decreased; and another 172 miRNAs showed an increased expression trend in IVm compared with that in BMd. Furthermore, two degradome sequencing libraries were also constructed to identify the target genes of these miRNAs. In total, 353 differentially expressed miRNAs between IVm and BMd were detected to be able to target 1,077 unigenes with 2,251 cleavage sites. Based on GO and KEGG analysis, these genes were found to be mainly related to transcription regulation and signal transduction. In addition, we selected 17 miRNAs and 22 corresponding target genes to screen the expression profiles when apple twigs were infected by Vm. The expression trends of most miRNAs/target genes were consist with the results of deep sequencing. Many of them may involve in the apple twig-Vm interaction by inducing/reducing their expression. What's more, miRNAs and their target genes regulate the apple twig-Vm interaction by forming many complicated regulation networks rather than one to one model. It is worth that a conserved miRNAs mdm-miR482b, which was down regulated in IVm compared with BMd, has 14 potential target genes, most of which are disease resistance related genes. This indicates that mdm-miR482b may play important roles in apple twig response to Vm. More important, the feedback regulation of sRNA pathway in apple twig is also very complex, and play critical role in the interaction between apple twig and Vm based on the results of expression analysis. In all, the results will provide insights into the crucial functions of miRNAs in the woody plant, apple tree-Vm interaction. PMID:29270184

De novo transcriptome characterization and gene expression profiling of the desiccation tolerant moss Bryum argenteum following rehydration.

PubMed

Gao, Bei; Zhang, Daoyuan; Li, Xiaoshuang; Yang, Honglan; Zhang, Yuanming; Wood, Andrew J

2015-05-28

The desiccation-tolerant moss Bryum argenteum is an important component of the Biological Soil Crusts (BSCs) found in the Gurbantunggut desert. Desiccation tolerance is defined as the ability to revive from the air dried state. To elucidate the molecular mechanisms related to desiccation tolerance, we employed RNA-Seq and digital gene expression (DGE) technologies to study the genome-wide expression profiles of the dehydration and rehydration processes in this important desert plant. We applied a two-step approach to investigate the gene expression profile upon rehydration in the moss Bryum argenteum using Illumina HiSeq2000 sequencing platform. First, a total of 57,247 transcript assembly contigs (TACs) were obtained from 54.79 million reads by de novo assembly, with an average length of 863 bp and N50 of 1,372 bp. Among the reconstructed TACs, 36,916 (64.5%) revealed similarity with existing protein sequences in the public databases. 23,509 and 21,607 TACs were assigned GO and KEGG annotation information, respectively. Second, samples were taken from 3 hydration stages: desiccated (Dry), rehydrated 2 h (R2) and rehydrated 24 h (R24), and DEG libraries were constructed for Differentially Expressed Genes (DEGs) discovery. 4,081 and 6,709 DEGs were identified in R2 and R24, compared with Dry, respectively. Compared to the desiccated sample, up-regulated genes after two hours of hydration are primarily related to stress responses. GO function enrichment network, EKGG metabolic pathway and MapMan analysis supports the idea of the rapid recovery of photosynthesis after 24 h of rehydration. We identified 770 transcription factors (TFs) which were classified into 50 TF families. 142 TF transcripts were up-regulated upon rehydration including 23 members of the ERF family. In this study, we constructed a pioneering, high-quality reference transcriptome in B. argenteum and generated three DGE libraries to elucidate the changes of gene expression upon rehydration. Expression profiles consistent with the rapid recovery of photosynthesis (at R2) and the re-establishment of a positive carbon balance following rehydration (at R24) were observed. Our study will extend our knowledge of bryophyte transcriptomes and provide further insight into the molecular mechanisms related to rehydration and desiccation-tolerance.

The UF/NCI family of hybrid computational phantoms representing the current US population of male and female children, adolescents, and adults—application to CT dosimetry

NASA Astrophysics Data System (ADS)

Geyer, Amy M.; O'Reilly, Shannon; Lee, Choonsik; Long, Daniel J.; Bolch, Wesley E.

2014-09-01

Substantial increases in pediatric and adult obesity in the US have prompted a major revision to the current UF/NCI (University of Florida/National Cancer Institute) family of hybrid computational phantoms to more accurately reflect current trends in larger body morphometry. A decision was made to construct the new library in a gridded fashion by height/weight without further reference to age-dependent weight/height percentiles as these become quickly outdated. At each height/weight combination, circumferential parameters were defined and used for phantom construction. All morphometric data for the new library were taken from the CDC NHANES survey data over the time period 1999-2006, the most recent reported survey period. A subset of the phantom library was then used in a CT organ dose sensitivity study to examine the degree to which body morphometry influences the magnitude of organ doses for patients that are underweight to morbidly obese in body size. Using primary and secondary morphometric parameters, grids containing 100 adult male height/weight bins, 93 adult female height/weight bins, 85 pediatric male height/weight bins and 73 pediatric female height/weight bins were constructed. These grids served as the blueprints for construction of a comprehensive library of patient-dependent phantoms containing 351 computational phantoms. At a given phantom standing height, normalized CT organ doses were shown to linearly decrease with increasing phantom BMI for pediatric males, while curvilinear decreases in organ dose were shown with increasing phantom BMI for adult females. These results suggest that one very useful application of the phantom library would be the construction of a pre-computed dose library for CT imaging as needed for patient dose-tracking.

Identification of drought-responsive genes in roots of upland rice (Oryza sativa L)

PubMed Central

Rabello, Aline R; Guimarães, Cléber M; Rangel, Paulo HN; da Silva, Felipe R; Seixas, Daniela; de Souza, Emanuel; Brasileiro, Ana CM; Spehar, Carlos R; Ferreira, Márcio E; Mehta, Ângela

2008-01-01

Background Rice (Oryza sativa L.) germplasm represents an extraordinary source of genes that control traits of agronomic importance such as drought tolerance. This diversity is the basis for the development of new cultivars better adapted to water restriction conditions, in particular for upland rice, which is grown under rainfall. The analyses of subtractive cDNA libraries and differential protein expression of drought tolerant and susceptible genotypes can contribute to the understanding of the genetic control of water use efficiency in rice. Results Two subtractive libraries were constructed using cDNA of drought susceptible and tolerant genotypes submitted to stress against cDNA of well-watered plants. In silico analysis revealed 463 reads, which were grouped into 282 clusters. Several genes expressed exclusively in the tolerant or susceptible genotypes were identified. Additionally, proteome analysis of roots from stressed plants was performed and 22 proteins putatively associated to drought tolerance were identified by mass spectrometry. Conclusion Several genes and proteins involved in drought-response, as well as genes with no described homologs were identified. Genes exclusively expressed in the tolerant genotype were, in general, related to maintenance of turgor and cell integrity. In contrast, in the susceptible genotype, expression of genes involved in protection against cell damage was not detected. Several protein families identified in the proteomic analysis were not detected in the cDNA analysis. There is an indication that the mechanisms of susceptibility to drought in upland rice are similar to those of lowland varieties. PMID:18922162

Versatile Cosmid Vectors for the Isolation, Expression, and Rescue of Gene Sequences: Studies with the Human α -globin Gene Cluster

NASA Astrophysics Data System (ADS)

Lau, Yun-Fai; Kan, Yuet Wai

1983-09-01

We have developed a series of cosmids that can be used as vectors for genomic recombinant DNA library preparations, as expression vectors in mammalian cells for both transient and stable transformations, and as shuttle vectors between bacteria and mammalian cells. These cosmids were constructed by inserting one of the SV2-derived selectable gene markers-SV2-gpt, SV2-DHFR, and SV2-neo-in cosmid pJB8. High efficiency of genomic cloning was obtained with these cosmids and the size of the inserts was 30-42 kilobases. We isolated recombinant cosmids containing the human α -globin gene cluster from these genomic libraries. The simian virus 40 DNA in these selectable gene markers provides the origin of replication and enhancer sequences necessary for replication in permissive cells such as COS 7 cells and thereby allows transient expression of α -globin genes in these cells. These cosmids and their recombinants could also be stably transformed into mammalian cells by using the respective selection systems. Both of the adult α -globin genes were more actively expressed than the embryonic zeta -globin genes in these transformed cell lines. Because of the presence of the cohesive ends of the Charon 4A phage in the cosmids, the transforming DNA sequences could readily be rescued from these stably transformed cells into bacteria by in vitro packaging of total cellular DNA. Thus, these cosmid vectors are potentially useful for direct isolation of structural genes.

Comparative transcriptome analysis of differentially expressed genes in foxtail millet (Setaria italica L.) during dehydration stress.

PubMed

Lata, Charu; Sahu, Pranav Pankaj; Prasad, Manoj

2010-03-19

Dehydration stress is one of the most important abiotic stresses that adversely influence crop growth and productivity. With the aim to understand the molecular mechanisms underlying dehydration stress tolerance in foxtail millet (Setaria italica L.), a drought tolerant crop, we examined its transcriptome changes at two time points (early and late) of dehydration stress. Two suppression subtractive hybridization (SSH) forward libraries were constructed from 21-day old seedlings of tolerant cv. Prasad at 0.5 and 6h PEG-induced dehydration stress. A total of 327 unique ESTs were identified from both libraries and were classified into 11 different categories according to their putative functions. The plant response against dehydration stress was complex, representing major transcripts involved in metabolism, stress, signaling, transcription regulation, translation and proteolysis. By Reverse Northern (RN) technique we identified the differential expression pattern of 327 transcripts, 86 (about 26%) of which showed > or = 1.7-fold induction. Further the obtained results were validated by quantitative real-time PCR (qRT-PCR) to have a comparative expression profiling of randomly chosen 9 up-regulated transcripts (> or =2.5 fold induction) between cv. Prasad (tolerant) and cv. Lepakshi (sensitive) upon dehydration stress. These transcripts showed a differential expression pattern in both cultivars at different time points of stress treatment as analyzed by qRT-PCR. The possible relationship of the identified transcripts with dehydration tolerance mechanism is discussed. Copyright 2010 Elsevier Inc. All rights reserved.

Identification of Anhydrobiosis-related Genes from an Expressed Sequence Tag Database in the Cryptobiotic Midge Polypedilum vanderplanki (Diptera; Chironomidae)*

PubMed Central

Cornette, Richard; Kanamori, Yasushi; Watanabe, Masahiko; Nakahara, Yuichi; Gusev, Oleg; Mitsumasu, Kanako; Kadono-Okuda, Keiko; Shimomura, Michihiko; Mita, Kazuei; Kikawada, Takahiro; Okuda, Takashi

2010-01-01

Some organisms are able to survive the loss of almost all their body water content, entering a latent state known as anhydrobiosis. The sleeping chironomid (Polypedilum vanderplanki) lives in the semi-arid regions of Africa, and its larvae can survive desiccation in an anhydrobiotic form during the dry season. To unveil the molecular mechanisms of this resistance to desiccation, an anhydrobiosis-related Expressed Sequence Tag (EST) database was obtained from the sequences of three cDNA libraries constructed from P. vanderplanki larvae after 0, 12, and 36 h of desiccation. The database contained 15,056 ESTs distributed into 4,807 UniGene clusters. ESTs were classified according to gene ontology categories, and putative expression patterns were deduced for all clusters on the basis of the number of clones in each library; expression patterns were confirmed by real-time PCR for selected genes. Among up-regulated genes, antioxidants, late embryogenesis abundant (LEA) proteins, and heat shock proteins (Hsps) were identified as important groups for anhydrobiosis. Genes related to trehalose metabolism and various transporters were also strongly induced by desiccation. Those results suggest that the oxidative stress response plays a central role in successful anhydrobiosis. Similarly, protein denaturation and aggregation may be prevented by marked up-regulation of Hsps and the anhydrobiosis-specific LEA proteins. A third major feature is the predicted increase in trehalose synthesis and in the expression of various transporter proteins allowing the distribution of trehalose and other solutes to all tissues. PMID:20833722

[Construction and characterization of a cDNA library from human liver tissue of cirrhosis].

PubMed

Chen, Xiao-hong; Chen, Zhi; Chen, Feng; Zhu, Hai-hong; Zhou, Hong-juan; Yao, Hang-ping

2005-03-01

To construct a cDNA library from human liver tissue of cirrhosis. The total RNA from human liver tissue of cirrhosis was extracted using Trizol method, and the mRNA was purified using mRNA purification kit. SMART technique and CDSIII/3' primer were used for first-strand cDNA synthesis. Long distance PCR was then used to synthesize the double-strand cDNA that was then digested by proteinase K and Sfi I, and was fractionated by CHOMA SPIN-400 column. The cDNA fragments longer than 0.4 kb were collected and ligated to lambdaTripl Ex2 vector. Then lambda-phage packaging reaction and library amplification were performed. The qualities of both unamplified and amplified cDNA libraries was strictly checked by conventional titer determination. Eleven plaques were randomly picked and tested using PCR with universal primers derived from the sequence flanking the vector. The titers of unamplifed and amplified libraries were 1.03 x 10(6) pfu/ml and 1.36 x 10(9) pfu/ml respectively. The percentages of recombinants from both libraries were 97.24 % in unamplified library and 99.02 % in amplified library. The lengths of the inserts were 1.02 kb in average (36.36 % 1 approximately equals 2 kb and 63.64 % 0.5 approximately equals 1.0 kb). A high quality cDNA library from human liver tissue of cirrhosis was constructed successfully, which can be used for screening and cloning new special genes associated with the occurrence of cirrhosis.

Informatic selection of a neural crest-melanocyte cDNA set for microarray analysis

PubMed Central

Loftus, S. K.; Chen, Y.; Gooden, G.; Ryan, J. F.; Birznieks, G.; Hilliard, M.; Baxevanis, A. D.; Bittner, M.; Meltzer, P.; Trent, J.; Pavan, W.

1999-01-01

With cDNA microarrays, it is now possible to compare the expression of many genes simultaneously. To maximize the likelihood of finding genes whose expression is altered under the experimental conditions, it would be advantageous to be able to select clones for tissue-appropriate cDNA sets. We have taken advantage of the extensive sequence information in the dbEST expressed sequence tag (EST) database to identify a neural crest-derived melanocyte cDNA set for microarray analysis. Analysis of characterized genes with dbEST identified one library that contained ESTs representing 21 neural crest-expressed genes (library 198). The distribution of the ESTs corresponding to these genes was biased toward being derived from library 198. This is in contrast to the EST distribution profile for a set of control genes, characterized to be more ubiquitously expressed in multiple tissues (P < 1 × 10−9). From library 198, a subset of 852 clustered ESTs were selected that have a library distribution profile similar to that of the 21 neural crest-expressed genes. Microarray analysis demonstrated the majority of the neural crest-selected 852 ESTs (Mel1 array) were differentially expressed in melanoma cell lines compared with a non-neural crest kidney epithelial cell line (P < 1 × 10−8). This was not observed with an array of 1,238 ESTs that was selected without library origin bias (P = 0.204). This study presents an approach for selecting tissue-appropriate cDNAs that can be used to examine the expression profiles of developmental processes and diseases. PMID:10430933

Functional metagenomics of oil-impacted mangrove sediments reveals high abundance of hydrolases of biotechnological interest.

PubMed

Ottoni, Júlia Ronzella; Cabral, Lucélia; de Sousa, Sanderson Tarciso Pereira; Júnior, Gileno Vieira Lacerda; Domingos, Daniela Ferreira; Soares Junior, Fábio Lino; da Silva, Mylenne Calciolari Pinheiro; Marcon, Joelma; Dias, Armando Cavalcante Franco; de Melo, Itamar Soares; de Souza, Anete Pereira; Andreote, Fernando Dini; de Oliveira, Valéria Maia

2017-07-01

Mangroves are located in coastal wetlands and are susceptible to the consequences of oil spills, what may threaten the diversity of microorganisms responsible for the nutrient cycling and the consequent ecosystem functioning. Previous reports show that high concentration of oil favors the incidence of epoxide hydrolases and haloalkane dehalogenases in mangroves. This finding has guided the goals of this study in an attempt to broaden the analysis to other hydrolases and thereby verify whether oil contamination interferes with the prevalence of particular hydrolases and their assigned microorganisms. For this, an in-depth survey of the taxonomic and functional microbial diversity recovered in a fosmid library (Library_Oil Mgv) constructed from oil-impacted Brazilian mangrove sediment was carried out. Fosmid DNA of the whole library was extracted and submitted to Illumina HiSeq sequencing. The resulting Library Oil_Mgv dataset was further compared with those obtained by direct sequencing of environmental DNA from Brazilian mangroves (from distinct regions and affected by distinct sources of contamination), focusing on hydrolases with potential use in biotechnological processes. The most abundant hydrolases found were proteases, esterases and amylases, with similar occurrence profile in all datasets. The main microbial groups harboring such hydrolase-encoding genes were distinct in each mangrove, and in the fosmid library these enzymes were mainly assigned to Chloroflexaceae (for amylases), Planctomycetaceae (for esterases) and Bradyrhizobiaceae (for proteases). Assembly and analysis of Library_Oil Mgv reads revealed three potentially novel enzymes, one epoxide hydrolase, one xylanase and one amylase, to be further investigated via heterologous expression assays.

Library Programs. Library Programs for the Handicapped. Fiscal Year 1987.

ERIC Educational Resources Information Center

Neff, Evaline B.

One in a series of published reports on selected Library Services and Construction Act (LSCA) program areas, this report presents the record of accomplishments in library services to the disabled during fiscal year 1987 nationwide, including programs in Guam, the Virgin Islands, and Puerto Rico. The typical services reported include the recordings…

Library Services to the Blind and Physically Handicapped.

ERIC Educational Resources Information Center

De Cleene, Clare

This report describes library services for the blind and physically handicapped supported by the Library Services and Construction Act (LSCA), Title I, funds during fiscal 1985. Trends in library services for the blind and physically handicapped determined by an examination of reports from individual states are briefly summarized for the areas of…

The Practicing Librarian: Public Library Parking Needs.

ERIC Educational Resources Information Center

Galvin, Hoyt

1978-01-01

Suggests standards for the numbers of parking spaces needed for a public library. From the annual Library Journal public library construction questionnaires, data were available on the number of parking spaces and the square foot size of the buildings reported; information on estimated needs was collected from the librarians in charge of each…

Hopkinsville-Christian County Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Nevels, Vada Germaine

The Hopkinsville-Christian County Library (Kentucky) conducted a project that involved recruitment, public awareness, basic literacy, collection development, tutoring, computer-assisted, other technology, and intergenerational/family programs. The project served a community of 50,000-100,000 people, and targeted the learning disabled,…

Mesa County Public Library District, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

LaDuke, Caryl

The Adult Reading Program, a project of the Mesa County Public Library District (Grand Junction, Colorado), involved recruitment, retention, coalition building, public awareness, training, rural oriented, basic literacy, collection development, tutoring, employment oriented, intergenerational/family, and English as a Second Language (ESL)…

Columbia County Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Cole, Lucy; Fraser, Ruth

The Columbia County Public Library (Lake City, Florida) conducted a project that involved recruitment, retention, public awareness, training, basic literacy, collection development, tutoring, computer- assisted, other technology, intergenerational/family, and English as a Second Language (ESL) programs. The project served a community of…

The Public Library Effectiveness Study: Final Report.

ERIC Educational Resources Information Center

Childers, Thomas; Van House, Nancy A.

This study investigated the construct of effectiveness as it applies to public libraries and developed a methodology that can be transferred to other types of libraries and organizations. The research team began by compiling a list of indicators that are commonly used to gauge library effectiveness within the areas of: (1) services access; (2)…

Trinucleotide cassettes increase diversity of T7 phage-displayed peptide library.

PubMed

Krumpe, Lauren R H; Schumacher, Kathryn M; McMahon, James B; Makowski, Lee; Mori, Toshiyuki

2007-10-05

Amino acid sequence diversity is introduced into a phage-displayed peptide library by randomizing library oligonucleotide DNA. We recently evaluated the diversity of peptide libraries displayed on T7 lytic phage and M13 filamentous phage and showed that T7 phage can display a more diverse amino acid sequence repertoire due to differing processes of viral morphogenesis. In this study, we evaluated and compared the diversity of a 12-mer T7 phage-displayed peptide library randomized using codon-corrected trinucleotide cassettes with a T7 and an M13 12-mer phage-displayed peptide library constructed using the degenerate codon randomization method. We herein demonstrate that the combination of trinucleotide cassette amino acid codon randomization and T7 phage display construction methods resulted in a significant enhancement to the functional diversity of a 12-mer peptide library. This novel library exhibited superior amino acid uniformity and order-of-magnitude increases in amino acid sequence diversity as compared to degenerate codon randomized peptide libraries. Comparative analyses of the biophysical characteristics of the 12-mer peptide libraries revealed the trinucleotide cassette-randomized library to be a unique resource. The combination of T7 phage display and trinucleotide cassette randomization resulted in a novel resource for the potential isolation of binding peptides for new and previously studied molecular targets.

Mutagenesis of diploid mammalian genes by gene entrapment

PubMed Central

Lin, Qing; Donahue, Sarah L.; Moore-Jarrett, Tracy; Cao, Shang; Osipovich, Anna B.; Ruley, H. Earl

2006-01-01

The present study describes a genome-wide method for biallelic mutagenesis in mammalian cells. Novel poly(A) gene trap vectors, which contain features for direct cloning vector–cell fusion transcripts and for post-entrapment genome engineering, were used to generate a library of 979 mutant ES cells. The entrapment mutations generally disrupted gene expression and were readily transmitted through the germline, establishing the library as a resource for constructing mutant mice. Cells homozygous for most entrapment loci could be isolated by selecting for enhanced expression of an inserted neomycin-resistance gene that resulted from losses of heterozygosity (LOH). The frequencies of LOH measured at 37 sites in the genome ranged from 1.3 × 10−5 to 1.2 × 10−4 per cell and increased with increasing distance from the centromere, implicating mitotic recombination in the process. The ease and efficiency of obtaining homozygous mutations will (i) facilitate genetic studies of gene function in cultured cells, (ii) permit genome-wide studies of recombination events that result in LOH and mediate a type of chromosomal instability important in carcinogenesis, and (iii) provide new strategies for phenotype-driven mutagenesis screens in mammalian cells. PMID:17062627

Analysis of genomic regions of Trichoderma harzianum IOC-3844 related to biomass degradation.

PubMed

Crucello, Aline; Sforça, Danilo Augusto; Horta, Maria Augusta Crivelente; dos Santos, Clelton Aparecido; Viana, Américo José Carvalho; Beloti, Lilian Luzia; de Toledo, Marcelo Augusto Szymanski; Vincentz, Michel; Kuroshu, Reginaldo Massanobu; de Souza, Anete Pereira

2015-01-01

Trichoderma harzianum IOC-3844 secretes high levels of cellulolytic-active enzymes and is therefore a promising strain for use in biotechnological applications in second-generation bioethanol production. However, the T. harzianum biomass degradation mechanism has not been well explored at the genetic level. The present work investigates six genomic regions (~150 kbp each) in this fungus that are enriched with genes related to biomass conversion. A BAC library consisting of 5,760 clones was constructed, with an average insert length of 90 kbp. The assembled BAC sequences revealed 232 predicted genes, 31.5% of which were related to catabolic pathways, including those involved in biomass degradation. An expression profile analysis based on RNA-Seq data demonstrated that putative regulatory elements, such as membrane transport proteins and transcription factors, are located in the same genomic regions as genes related to carbohydrate metabolism and exhibit similar expression profiles. Thus, we demonstrate a rapid and efficient tool that focuses on specific genomic regions by combining a BAC library with transcriptomic data. This is the first BAC-based structural genomic study of the cellulolytic fungus T. harzianum, and its findings provide new perspectives regarding the use of this species in biomass degradation processes.

Analysis of Genomic Regions of Trichoderma harzianum IOC-3844 Related to Biomass Degradation

PubMed Central

Crucello, Aline; Sforça, Danilo Augusto; Horta, Maria Augusta Crivelente; dos Santos, Clelton Aparecido; Viana, Américo José Carvalho; Beloti, Lilian Luzia; de Toledo, Marcelo Augusto Szymanski; Vincentz, Michel; Kuroshu, Reginaldo Massanobu; de Souza, Anete Pereira

2015-01-01

Trichoderma harzianum IOC-3844 secretes high levels of cellulolytic-active enzymes and is therefore a promising strain for use in biotechnological applications in second-generation bioethanol production. However, the T. harzianum biomass degradation mechanism has not been well explored at the genetic level. The present work investigates six genomic regions (~150 kbp each) in this fungus that are enriched with genes related to biomass conversion. A BAC library consisting of 5,760 clones was constructed, with an average insert length of 90 kbp. The assembled BAC sequences revealed 232 predicted genes, 31.5% of which were related to catabolic pathways, including those involved in biomass degradation. An expression profile analysis based on RNA-Seq data demonstrated that putative regulatory elements, such as membrane transport proteins and transcription factors, are located in the same genomic regions as genes related to carbohydrate metabolism and exhibit similar expression profiles. Thus, we demonstrate a rapid and efficient tool that focuses on specific genomic regions by combining a BAC library with transcriptomic data. This is the first BAC-based structural genomic study of the cellulolytic fungus T. harzianum, and its findings provide new perspectives regarding the use of this species in biomass degradation processes. PMID:25836973

Discovery of novel and differentially expressed microRNAs between fetal and adult backfat in cattle.

PubMed

Sun, Jiajie; Zhou, Yang; Cai, Hanfang; Lan, Xianyong; Lei, Chuzhao; Zhao, Xin; Zhang, Chunlei; Chen, Hong

2014-01-01

The posttranscriptional gene regulation mediated by microRNAs (miRNAs) plays an important role in various species. Recently, a large number of miRNAs and their expression patterns have been identified. However, to date, limited miRNAs have been reported to modulate adipogenesis and lipid deposition in beef cattle. Total RNAs from Chinese Qinchuan bovine backfat at fetal and adult stages were used to construct small RNA libraries for Illumina next-generation sequencing. A total of 13,915,411 clean reads were obtained from a fetal library and 14,244,946 clean reads from an adult library. In total, 475 known and 36 novel miRNA candidates from backfat were identified. The nucleotide bias, base editing, and family of the known miRNAs were also analyzed. Based on stem-loop qPCR, 15 specific miRNAs were detected, and the results showed that bta-miRNAn25 and miRNAn26 were highly expressed in backfat tissue, suggesting these small RNAs play a role in the development and maintenance of bovine subcutaneous fat tissue. Putative targets for miRNAn25 and miRNAn26 were predicted, and the 61 most significant target transcripts were related to lipid and fatty acid metabolism. Of interest, the canonical pathway and gene networks analyses revealed that PPARα/RXRα activation and LXR/RXR activation were important components of the gene interaction hierarchy results. In the present study, we explored the backfat miRNAome differences between cattle of different developmental stages, expanding the expression repertoire of bovine miRNAs that could contribute to further studies on the fat development of cattle. Predication of target genes analysis of miRNA25 and miRNA26 also showed potential gene networks that affect lipid and fatty acid metabolism. These results may help in the design of new intervention strategies to improve beef quality.

Discovery of Novel and Differentially Expressed MicroRNAs between Fetal and Adult Backfat in Cattle

PubMed Central

Sun, Jiajie; Zhou, Yang; Cai, Hanfang; Lan, Xianyong; Lei, Chuzhao; Zhao, Xin; Zhang, Chunlei; Chen, Hong

2014-01-01

The posttranscriptional gene regulation mediated by microRNAs (miRNAs) plays an important role in various species. Recently, a large number of miRNAs and their expression patterns have been identified. However, to date, limited miRNAs have been reported to modulate adipogenesis and lipid deposition in beef cattle. Total RNAs from Chinese Qinchuan bovine backfat at fetal and adult stages were used to construct small RNA libraries for Illumina next-generation sequencing. A total of 13,915,411 clean reads were obtained from a fetal library and 14,244,946 clean reads from an adult library. In total, 475 known and 36 novel miRNA candidates from backfat were identified. The nucleotide bias, base editing, and family of the known miRNAs were also analyzed. Based on stem-loop qPCR, 15 specific miRNAs were detected, and the results showed that bta-miRNAn25 and miRNAn26 were highly expressed in backfat tissue, suggesting these small RNAs play a role in the development and maintenance of bovine subcutaneous fat tissue. Putative targets for miRNAn25 and miRNAn26 were predicted, and the 61 most significant target transcripts were related to lipid and fatty acid metabolism. Of interest, the canonical pathway and gene networks analyses revealed that PPARα/RXRα activation and LXR/RXR activation were important components of the gene interaction hierarchy results. In the present study, we explored the backfat miRNAome differences between cattle of different developmental stages, expanding the expression repertoire of bovine miRNAs that could contribute to further studies on the fat development of cattle. Predication of target genes analysis of miRNA25 and miRNA26 also showed potential gene networks that affect lipid and fatty acid metabolism. These results may help in the design of new intervention strategies to improve beef quality. PMID:24587298

School Partners in ILLINET. Automation Options for School Library Resource Sharing in Illinois. Final Report [and] Partners in ILLINET. Special Report.

ERIC Educational Resources Information Center

Howrey, Mary M.

This study was funded by the Library Services and Construction Act (LSCA) to enable the Illinois School Library Media Association (ISLMA) to plan the automation of the state's school libraries. The research was intended to identify current national programs of interest to ISLMA, identify current automation programs within Illinois library systems,…

DeKalb County Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Des Enfants, Sherry

This DeKalb County Public Library family literacy project final performance report begins with a section that provides quantitative data on the project. The next section compares actual accomplishments to the following project objectives for fiscal year 1993: (1) to update eight existing literacy collections in branch libraries by the addition of…

Clear Purpose...Complete Commitment: A Long-Range Program To Provide Louisianians with Library and Information Services Adequate to Their Needs, 1993-1997.

ERIC Educational Resources Information Center

Jaques, Thomas F.

This long range plan, which was prepared in compliance with the Library Services and Construction Act (LSCA), begins with an overview of the library public and the state library agency in Louisiana. Identification of needs and action plans are presented in the following goal areas: (1) improving state library administration; (2) extending services…

EST resources and establishment and validation of a 16k cDNA microarray from Atlantic cod (Gadus morhua).

PubMed

Edvardsen, Rolf B; Malde, Ketil; Mittelholzer, Christian; Taranger, Geir Lasse; Nilsen, Frank

2011-03-01

The Atlantic cod, Gadus morhua, is an important species both for traditional fishery and increasingly also in fish farming. The Atlantic cod is also under potential threat from various environmental changes such as pollution and climate change, but the biological impact of such changes are not well known, in particular when it comes to sublethal effects that can be difficult to assert. Modern molecular and genomic approaches have revolutionized biological research during the last decade, and offer new avenues to study biological functions and e.g. the impact of anthropogenic activities at different life-stages for a given organism. In order to develop genomic data and genomic tools for Atlantic cod we conducted a program were we constructed 20 cDNA libraries, and produced and analyzed 44006 expressed sequence tags (ESTs) from these. Several tissues are represented in the multiple cDNA libraries, that differ in either sexual maturation or immulogical stimulation. This approach allowed us to identify genes that are expressed in particular tissues, life-stages or in response to specific stimuli, and also gives us information about potential functions of the transcripts. The ESTs were used to construct a 16k cDNA microarray to further investigate the cod transcriptome. Microarray analyses were preformed on pylorus, pituitary gland, spleen and testis of sexually maturing male cod. The four different tissues displayed tissue specific transcriptomes demonstrating that the cDNA array is working as expected and will prove to be a powerful tool in further experiments. Copyright © 2010 Elsevier Inc. All rights reserved.

Reiterative Recombination for the in vivo assembly of libraries of multigene pathways.

PubMed

Wingler, Laura M; Cornish, Virginia W

2011-09-13

The increasing sophistication of synthetic biology is creating a demand for robust, broadly accessible methodology for constructing multigene pathways inside of the cell. Due to the difficulty of rationally designing pathways that function as desired in vivo, there is a further need to assemble libraries of pathways in parallel, in order to facilitate the combinatorial optimization of performance. While some in vitro DNA assembly methods can theoretically make libraries of pathways, these techniques are resource intensive and inherently require additional techniques to move the DNA back into cells. All previously reported in vivo assembly techniques have been low yielding, generating only tens to hundreds of constructs at a time. Here, we develop "Reiterative Recombination," a robust method for building multigene pathways directly in the yeast chromosome. Due to its use of endonuclease-induced homologous recombination in conjunction with recyclable markers, Reiterative Recombination provides a highly efficient, technically simple strategy for sequentially assembling an indefinite number of DNA constructs at a defined locus. In this work, we describe the design and construction of the first Reiterative Recombination system in Saccharomyces cerevisiae, and we show that it can be used to assemble multigene constructs. We further demonstrate that Reiterative Recombination can construct large mock libraries of at least 10(4) biosynthetic pathways. We anticipate that our system's simplicity and high efficiency will make it a broadly accessible technology for pathway construction and render it a valuable tool for optimizing pathways in vivo.

Reiterative Recombination for the in vivo assembly of libraries of multigene pathways

PubMed Central

Wingler, Laura M.; Cornish, Virginia W.

2011-01-01

The increasing sophistication of synthetic biology is creating a demand for robust, broadly accessible methodology for constructing multigene pathways inside of the cell. Due to the difficulty of rationally designing pathways that function as desired in vivo, there is a further need to assemble libraries of pathways in parallel, in order to facilitate the combinatorial optimization of performance. While some in vitro DNA assembly methods can theoretically make libraries of pathways, these techniques are resource intensive and inherently require additional techniques to move the DNA back into cells. All previously reported in vivo assembly techniques have been low yielding, generating only tens to hundreds of constructs at a time. Here, we develop “Reiterative Recombination,” a robust method for building multigene pathways directly in the yeast chromosome. Due to its use of endonuclease-induced homologous recombination in conjunction with recyclable markers, Reiterative Recombination provides a highly efficient, technically simple strategy for sequentially assembling an indefinite number of DNA constructs at a defined locus. In this work, we describe the design and construction of the first Reiterative Recombination system in Saccharomyces cerevisiae, and we show that it can be used to assemble multigene constructs. We further demonstrate that Reiterative Recombination can construct large mock libraries of at least 104 biosynthetic pathways. We anticipate that our system’s simplicity and high efficiency will make it a broadly accessible technology for pathway construction and render it a valuable tool for optimizing pathways in vivo. PMID:21876185

Isolation and characterization of a cDNA encoding a lipid transfer protein expressed in 'Valencia' orange during abscission.

PubMed

Wu, Zhencai; Burns, Jacqueline K

2003-04-01

The genetics and expression of a lipid transfer protein (LTP) gene was examined during abscission of mature fruit of 'Valencia' orange. A cDNA encoding an LTP, CsLTP, was isolated from a cDNA subtraction library constructed from mature fruit abscission zones 48 h after application of a mature fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-pyrazole (CMN-pyrazole). A full-length cDNA clone of 652 nucleotides was isolated using 5' and 3' RACE followed by cDNA library screening and PCR amplification. The cDNA clone encoded a protein of 155 amino acid residues with a molecular mass and isoelectric point of 9.18 kDa and 9.12, respectively. A partial genomic clone of 505 nucleotides containing one intron of 101 base pairs was amplified from leaf genomic DNA. Southern blot hybridization demonstrated that at least two closely related CsLTP genes are present in 'Valencia' orange. Temporal expression patterns in mature fruit abscission zones were examined by northern hybridization. Increased expression of CsLTP mRNA was detected in RNA of mature fruit abscission zones 6, 24, 48, and 72 h after application of a non-specific abscission agent, ethephon. Low expression of CsLTP transcripts was observed after treatment of CMN-pyrazole until 24 h after application. After this time, expression markedly increased. The results suggest that CsLTP has a role in the abscission process, possibly by assisting transport of cutin monomers to the fracture plane of the abscission zone or through its anti-microbial activity by reducing the potential of microbial attack.

High yield of functional metagenomic library from mangroves constructed in fosmid vector.

PubMed

Gonçalves, A C S; dos Santos, A C F; dos Santos, T F; Pessoa, T B A; Dias, J C T; Rezende, R P

2015-10-02

In the present study, metagenomic technique and fosmid vectors were used to construct a library of clones for exploring the biotechnological potential of mangrove soils by isolation of functional genes encoding hydrolytic enzymes. The library was built with genomic DNA from the soil samples of mangrove sediments and the functional screening of 1824 clones (~64 Mbp) was performed to detect the hydrolytic activity specific for cellulases, amylases (at acidic, neutral and basic pH), lipases/esterases, proteases, and nitrilases. Significant numbers of clones, positive for the tested enzyme activities were obtained. Our results indicate the importance and biotechnological potential of mangrove soils especially when compared to those obtained using other soil metagenomic libraries.

Construction of a metagenomic DNA library of sponge symbionts and screening of antibacterial metabolites

NASA Astrophysics Data System (ADS)

Chen, Juan; Zhu, Tianjiao; Li, Dehai; Cui, Chengbin; Fang, Yuchun; Liu, Hongbing; Liu, Peipei; Gu, Qianqun; Zhu, Weiming

2006-04-01

To study the bioactive metabolites produced by sponge-derived uncultured symbionts, a metagenomic DNA library of the symbionts of sponge Gelliodes gracilis was constructed. The average size of DNA inserts in the library was 20 kb. This library was screened for antibiotic activity using paper dise assaying. Two clones displayed the antibacterial activity against Micrococcus tetragenus. The metabolites of these two clones were analyzed through HPLC. The result showed that their metabolites were quite different from those of the host E. coli DH5α and the host containing vector pHZ132. This study may present a new approach to exploring bioactive metabolites of sponge symbionts.

Research on Energy-saving Shape Design of High School Library Building in Cold Region

NASA Astrophysics Data System (ADS)

Hui, Zhao; Weishuang, Xie; Zirui, Tong

2017-11-01

Considering climatic characteristics in cold region, existing high school libraries in Changchun are researched according to investigation of real conditions of these library buildings. Mathematical analysis and CAD methods are used to summarize the relation between building shape and building energy saving of high school library. Strategies are put forward for sustainable development of high school library building in cold region, providing reliable design basis for construction of high school libraries in Changchun.

Molecular cloning and functional characterization of borneol dehydrogenase from the glandular trichomes of Lavandula x intermedia.

PubMed

Sarker, Lukman S; Galata, Mariana; Demissie, Zerihun A; Mahmoud, Soheil S

2012-12-15

Several varieties of Lavandula x intermedia (lavandins) are cultivated for their essential oils (EOs) for use in cosmetic, hygiene and personal care products. These EOs are mainly constituted of monoterpenes including camphor, which contributes an off odor reducing the olfactory appeal of the oil. We have recently constructed a cDNA library from the glandular trichomes (the sites of EO synthesis) of L. x intermedia plants. Here, we describe the cloning of a borneol dehydrogenase cDNA (LiBDH) from this library. The 780 bp open reading frame of the cDNA encoded a 259 amino acid short chain alcohol dehydrogenase with a predicted molecular mass of ca. 27.5 kDa. The recombinant LiBDH was expressed in Escherichia coli, purified by Ni-NTA agarose affinity chromatography, and functionally characterized in vitro. The bacterially produced enzyme specifically converted borneol to camphor as the only product with K(m) and k(cat) values of 53 μM and 4.0 × 10(-4) s(-1), respectively. The LiBDH transcripts were specifically expressed in glandular trichomes of mature flowers indicating that like other Lavandula monoterpene synthases the expression of this gene is regulated in a tissue-specific manner. The cloning of LiBDH has far reaching implications in improving the quality of Lavandula EOs through metabolic engineering. Copyright © 2012 Elsevier Inc. All rights reserved.

Physiological response and microRNA expression profiles in head kidney of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to acute cold stress.

PubMed

Qiang, Jun; Cui, Yan T; Tao, Fan Y; Bao, Wen J; He, Jie; Li, Xia H; Xu, Pao; Sun, Lan Y

2018-01-09

Cold stress has a serious impact on the overwintering survival and yield of genetically improved farmed tilapia (GIFT, Oreochromis niloticus). Understanding the physiological and molecular regulation mechanisms of low-temperature adaptation is necessary to help breed new tolerant strains. The semi-lethal low temperature of juvenile GIFT at 96 h was determined as 9.4 °C. We constructed and sequenced two small RNA libraries from head kidney tissues, one for the control (CO) group and one for the 9.4 °C-stressed (LTS) group, and identified 1736 and 1481 known microRNAs (miRNAs), and 164 and 152 novel miRNAs in the CO and LTS libraries, respectively. We verify the expression of nine up-regulated miRNAs and eight down-regulation miRNAs by qRT-PCR, and found their expression patterns were consistent with the sequencing results. We found that cold stress may have produced dysregulation of free radical and lipid metabolism, decreased superoxide dismutase activity, reduced respiratory burst and phagocytic activity of macrophages, increased malondialdehyde content, and adversely affected the physiological adaptation of GIFT, eventually leading to death. This study revealed interactions among miRNAs and signal regulated pathways in GIFT under cold stress that may help to understand the pathways involved in cold resistance.

Isolation and characterization of a metallothionein-1 protein in Chloris virgata Swartz that enhances stress tolerances to oxidative, salinity and carbonate stress in Saccharomyces cerevisiae.

PubMed

Nishiuchi, Shunsaku; Liu, Shenkui; Takano, Tetsuo

2007-08-01

Chloris virgata Swartz (C. virgata) is a gramineous wild plant that is found in alkaline soil areas in northeast China and is highly tolerant to carbonate stress. We constructed a cDNA library from C. virgata seedlings treated with NaHCO(3), and isolated a type 1 metallothionein (MT1) gene (ChlMT1: AB294238) from the library. The amino acid sequence of ChlMT1 contained 12 cysteine residues that constituted the Cys-X-Cys (X = amino acid except Cys) motifs in the N- and C-terminal regions. Northern hybridization showed that expression of ChlMT1 was induced by several abiotic stresses, from salts (NaCl and NaHCO(3)), a ROS inducer (paraquat), and metals (CuSO(4), ZnSO(4), and CoCl(2)). ChlMT1 expression in leaf was induced by 200 mM NaCl and 100 mM NaHCO(3). About 5 microM Paraquat, 500 microM Zn(2+), and 500 microM Co(2+) also induced expression of ChlMT1 in leaf after 6 h, and 100 microM Cu(2+) induced it after 24 h. Saccharomyces cerevisiae when transformed with the ChlMT1 gene had dramatically increased tolerances to salts (NaCl and NaHCO(3)) and ROS.

Transcriptional profiling reveals the expression of novel genes in response to various stimuli in the human dermatophyte Trichophyton rubrum

PubMed Central

2010-01-01

Background Cutaneous mycoses are common human infections among healthy and immunocompromised hosts, and the anthropophilic fungus Trichophyton rubrum is the most prevalent microorganism isolated from such clinical cases worldwide. The aim of this study was to determine the transcriptional profile of T. rubrum exposed to various stimuli in order to obtain insights into the responses of this pathogen to different environmental challenges. Therefore, we generated an expressed sequence tag (EST) collection by constructing one cDNA library and nine suppression subtractive hybridization libraries. Results The 1388 unigenes identified in this study were functionally classified based on the Munich Information Center for Protein Sequences (MIPS) categories. The identified proteins were involved in transcriptional regulation, cellular defense and stress, protein degradation, signaling, transport, and secretion, among other functions. Analysis of these unigenes revealed 575 T. rubrum sequences that had not been previously deposited in public databases. Conclusion In this study, we identified novel T. rubrum genes that will be useful for ORF prediction in genome sequencing and facilitating functional genome analysis. Annotation of these expressed genes revealed metabolic adaptations of T. rubrum to carbon sources, ambient pH shifts, and various antifungal drugs used in medical practice. Furthermore, challenging T. rubrum with cytotoxic drugs and ambient pH shifts extended our understanding of the molecular events possibly involved in the infectious process and resistance to antifungal drugs. PMID:20144196

Progress in gene targeting and gene therapy for retinitis pigmentosa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farrar, G.J.; Humphries, M.M.; Erven, A.

1994-09-01

Previously, we localized disease genes involved in retinitis pigmentosa (RP), an inherited retinal degeneration, close to the rhodopsin and peripherin genes on 3q and 6p. Subsequently, we and others identified mutations in these genes in RP patients. Currently animal models for human retinopathies are being generated using gene targeting by homologous recombination in embryonic stem (ES) cells. Genomic clones for retinal genes including rhodopsin and peripherin have been obtained from a phage library carrying mouse DNA isogenic with the ES cell line (CC1.2). The peripherin clone has been sequenced to establish the genomic structure of the mouse gene. Targeting vectorsmore » for rhodopsin and peripherin including a neomycin cassette for positive selection and thymidine kinase genes enabling selection against random intergrants are under construction. Progress in vector construction will be presented. Simultaneously we are developing systems for delivery of gene therapies to retinal tissues utilizing replication-deficient adenovirus (Ad5). Efficacy of infection subsequent to various methods of intraocular injection and with varying viral titers is being assayed using an adenovirus construct containing a CMV promoter LacZ fusion as reporter and the range of tissues infected and the level of duration of LacZ expression monitored. Viral constructs with the LacZ reporter gene under the control of retinal specific promoters such as rhodopsin and IRBP cloned into pXCJL.1 are under construction. An update on developments in photoreceptor cell-directed expression of virally delivered genes will be presented.« less

Annual Program; Library Services and Construction Act 1972-1973. Additional LSCA FY '73 Funds.

ERIC Educational Resources Information Center

South Carolina State Library, Columbia.

The South Carolina Annual Program, Library Services and Construction Act (LSCA), 1972-73, was originally developed on the basis of the funding level approved by the administration for 1973-74. Following court decisions on suits challenging impoundment of LSCA funds, additional monies became available under the act. This Supplement to the Annual…

Random mutagenesis of BoNT/E Hc nanobody to construct a secondary phage-display library.

PubMed

Shahi, B; Mousavi Gargari, S L; Rasooli, I; Rajabi Bazl, M; Hoseinpoor, R

2014-08-01

To construct secondary mutant phage-display library of recombinant single variable domain (VHH) against botulinum neurotoxin E by error-prone PCR. The gene coding for specific VHH derived from the camel immunized with binding domain of botulinum neurotoxin E (BoNT/E) was amplified by error-prone PCR. Several biopanning rounds were used to screen the phage-displaying BoNT/E Hc nanobodies. The final nanobody, SHMR4, with increased affinity recognized BoNT/E toxin with no cross-reactivity with other antigens especially with related BoNT toxins. The constructed nanobody could be a suitable candidate for VHH-based biosensor production to detect the Clostridium botulinum type E. Diagnosis and treatment of botulinum neurotoxins are important. Generation of high-affinity antibodies based on the construction of secondary libraries using affinity maturation step leads to the development of reagents for precise diagnosis and therapy. © 2014 The Society for Applied Microbiology.

Alabama Public Library Service, 1987 Annual Report.

ERIC Educational Resources Information Center

Alabama Public Library Service, Montgomery.

Designed to provide an overview of the range and quality of services provided by the Alabama Public Library Service (APLS), this annual report focuses on the 1987 activities of APLS. A report on the activities of the Library Development Division shows the allocation of state aid and Library Services and Construction Act (LCSA) Titles I and III…

Marin County Free Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Mooney, Sharon Lopez

The West Marin Literacy Project, a project of the Marin County Free Library (San Rafael, California), involved recruitment, retention, coalition building, public awareness, training, rural oriented, tutoring, computer- assisted, intergenerational/family, and English as a Second Language (ESL) programs. The project served a community of under…

The Impact of Academic Library Resources on Undergraduates' Degree Completion

ERIC Educational Resources Information Center

Soria, Krista M.; Fransen, Jan; Nackerud, Shane

2017-01-01

The purpose of this study was to examine the impact of first-year undergraduates' (n = 5,368) use of academic library resources in their first year on their degree completion or continued enrollment after four years of study. Propensity score matching techniques were used to construct treatment (library users) and control (library nonusers) groups…

Martinsburg-Berkeley County Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Hess, Therese M.

The Martinsburg-Berkeley County Public Library (West Virginia) conducted a project that involved recruitment, retention, coalition building, public awareness, training, basic literacy, collection development, tutoring, computer assisted, other technology, and English as a Second Language (ESL) programs. The project served a three-county community…

Vigo County Public Library Mediamobile: Evaluation of a Library Services Act Project.

ERIC Educational Resources Information Center

Pahl, E. Patricia; Pahl, Thomas L.

The Vigo County (Indiana) Public Library received a two-year grant, under the Library Services and Construction Act, to improve services to the disadvantaged in urban and rural areas. A program was developed to use a converted bookmobile to deliver films, records, video tape, viewmasters, tape recorders, and other "new" media to the OEO…

Report of Library Services and Construction Act Project # 2842, July 1 - December 31, 1967.

ERIC Educational Resources Information Center

Los Angeles Public Library, CA.

In this six month period of the Los Angeles Public Library's project to extend service to the disadvantaged a full time public relations assistant was hired. Attempts were made to evaluate special activities and the Library Administration considered implications of the project for the Library's service program. This document includes reports from…

Strong spurious transcription likely contributes to DNA insert bias in typical metagenomic clone libraries.

PubMed

Lam, Kathy N; Charles, Trevor C

2015-01-01

Clone libraries provide researchers with a powerful resource to study nucleic acid from diverse sources. Metagenomic clone libraries in particular have aided in studies of microbial biodiversity and function, and allowed the mining of novel enzymes. Libraries are often constructed by cloning large inserts into cosmid or fosmid vectors. Recently, there have been reports of GC bias in fosmid metagenomic libraries, and it was speculated to be a result of fragmentation and loss of AT-rich sequences during cloning. However, evidence in the literature suggests that transcriptional activity or gene product toxicity may play a role. To explore possible mechanisms responsible for sequence bias in clone libraries, we constructed a cosmid library from a human microbiome sample and sequenced DNA from different steps during library construction: crude extract DNA, size-selected DNA, and cosmid library DNA. We confirmed a GC bias in the final cosmid library, and we provide evidence that the bias is not due to fragmentation and loss of AT-rich sequences but is likely occurring after DNA is introduced into Escherichia coli. To investigate the influence of strong constitutive transcription, we searched the sequence data for promoters and found that rpoD/σ(70) promoter sequences were underrepresented in the cosmid library. Furthermore, when we examined the genomes of taxa that were differentially abundant in the cosmid library relative to the original sample, we found the bias to be more correlated with the number of rpoD/σ(70) consensus sequences in the genome than with simple GC content. The GC bias of metagenomic libraries does not appear to be due to DNA fragmentation. Rather, analysis of promoter sequences provides support for the hypothesis that strong constitutive transcription from sequences recognized as rpoD/σ(70) consensus-like in E. coli may lead to instability, causing loss of the plasmid or loss of the insert DNA that gives rise to the transcription. Despite widespread use of E. coli to propagate foreign DNA in metagenomic libraries, the effects of in vivo transcriptional activity on clone stability are not well understood. Further work is required to tease apart the effects of transcription from those of gene product toxicity.

A Feminist Paradigm for Library and Information Science.

ERIC Educational Resources Information Center

Hannigan, Jane Anne; Crew, Hilary

1993-01-01

Discussion of feminist scholarship and feminist thinking focuses on feminism in librarianship. Topics addressed include research methodologies; implications for library and information science; a feminist model, including constructed knowledge; standpoint theory; benefits of feminist scholarship; and a library model. (Contains 14 references.) (LRW)

Construction of a Lotus japonicus late nodulin expressed sequence tag library and identification of novel nodule-specific genes.

PubMed Central

Szczyglowski, K; Hamburger, D; Kapranov, P; de Bruijn, F J

1997-01-01

A range of novel expressed sequence tags (ESTs) associated with late developmental events during nodule organogenesis in the legume Lotus japonicus were identified using mRNA differential display; 110 differentially displayed polymerase chain reaction products were cloned and analyzed. Of 88 unique cDNAs obtained, 22 shared significant homology to DNA/protein sequences in the respective databases. This group comprises, among others, a nodule-specific homolog of protein phosphatase 2C, a peptide transporter protein, and a nodule-specific form of cytochrome P450. RNA gel-blot analysis of 16 differentially displayed ESTs confirmed their nodule-specific expression pattern. The kinetics of mRNA accumulation of the majority of the ESTs analyzed were found to resemble the expression pattern observed for the L. japonicus leghemoglobin gene. These results indicate that the newly isolated molecular markers correspond to genes induced during late developmental stages of L. japonicus nodule organogenesis and provide important, novel tools for the study of nodulation. PMID:9276951

Expression of the Pasteurella haemolytica leukotoxin is inhibited by a locus that encodes an ATP-binding cassette homolog.

PubMed Central

Highlander, S K; Wickersham, E A; Garza, O; Weinstock, G M

1993-01-01

Multicopy and single-copy chromosomal fusions between the Pasteurella haemolytica leukotoxin regulatory region and the Escherichia coli beta-galactosidase gene have been constructed. These fusions were used as reporters to identify and isolate regulators of leukotoxin expression from a P. haemolytica cosmid library. A cosmid clone, which inhibited leukotoxin expression from multicopy and single-copy protein fusions, was isolated and found to contain the complete leukotoxin gene cluster plus additional upstream sequences. The locus responsible for inhibition of expression from leukotoxin-beta-galactosidase fusions was mapped within these upstream sequences, by transposon mutagenesis with Tn5, and its DNA sequence was determined. The inhibitory activity was found to be associated with a predicted 440-amino-acid reading frame (lapA) that lies within a four-gene arginine transport locus. LapA is predicted to be the nucleotide-binding component of this transport system and shares homology with the Clp family of proteases. Images PMID:8359916

The Human EST Ontology Explorer: a tissue-oriented visualization system for ontologies distribution in human EST collections.

PubMed

Merelli, Ivan; Caprera, Andrea; Stella, Alessandra; Del Corvo, Marcello; Milanesi, Luciano; Lazzari, Barbara

2009-10-15

The NCBI dbEST currently contains more than eight million human Expressed Sequenced Tags (ESTs). This wide collection represents an important source of information for gene expression studies, provided it can be inspected according to biologically relevant criteria. EST data can be browsed using different dedicated web resources, which allow to investigate library specific gene expression levels and to make comparisons among libraries, highlighting significant differences in gene expression. Nonetheless, no tool is available to examine distributions of quantitative EST collections in Gene Ontology (GO) categories, nor to retrieve information concerning library-dependent EST involvement in metabolic pathways. In this work we present the Human EST Ontology Explorer (HEOE) http://www.itb.cnr.it/ptp/human_est_explorer, a web facility for comparison of expression levels among libraries from several healthy and diseased tissues. The HEOE provides library-dependent statistics on the distribution of sequences in the GO Direct Acyclic Graph (DAG) that can be browsed at each GO hierarchical level. The tool is based on large-scale BLAST annotation of EST sequences. Due to the huge number of input sequences, this BLAST analysis was performed with the aid of grid computing technology, which is particularly suitable to address data parallel task. Relying on the achieved annotation, library-specific distributions of ESTs in the GO Graph were inferred. A pathway-based search interface was also implemented, for a quick evaluation of the representation of libraries in metabolic pathways. EST processing steps were integrated in a semi-automatic procedure that relies on Perl scripts and stores results in a MySQL database. A PHP-based web interface offers the possibility to simultaneously visualize, retrieve and compare data from the different libraries. Statistically significant differences in GO categories among user selected libraries can also be computed. The HEOE provides an alternative and complementary way to inspect EST expression levels with respect to approaches currently offered by other resources. Furthermore, BLAST computation on the whole human EST dataset was a suitable test of grid scalability in the context of large-scale bioinformatics analysis. The HEOE currently comprises sequence analysis from 70 non-normalized libraries, representing a comprehensive overview on healthy and unhealthy tissues. As the analysis procedure can be easily applied to other libraries, the number of represented tissues is intended to increase.

A novel regulatory element (E77) isolated from CHO-K1 genomic DNA enhances stable gene expression in Chinese hamster ovary cells.

PubMed

Kang, Shin-Young; Kim, Yeon-Gu; Kang, Seunghee; Lee, Hong Weon; Lee, Eun Gyo

2016-05-01

Vectors flanked by regulatory DNA elements have been used to generate stable cell lines with high productivity and transgene stability; however, regulatory elements in Chinese hamster ovary (CHO) cells, which are the most widely used mammalian cells in biopharmaceutical production, are still poorly understood. We isolated a novel gene regulatory element from CHO-K1 cells, designated E77, which was found to enhance the stable expression of a transgene. A genomic library was constructed by combining CHO-K1 genomic DNA fragments with a CMV promoter-driven GFP expression vector, and the E77 element was isolated by screening. The incorporation of the E77 regulatory element resulted in the generation of an increased number of clones with high expression, thereby enhancing the expression level of the transgene in the stable transfectant cell pool. Interestingly, the E77 element was found to consist of two distinct fragments derived from different locations in the CHO genome shotgun sequence. High and stable transgene expression was obtained in transfected CHO cells by combining these fragments. Additionally, the function of E77 was found to be dependent on its site of insertion and specific orientation in the vector construct. Our findings demonstrate that stable gene expression mediated by the CMV promoter in CHO cells may be improved by the isolated novel gene regulatory element E77 identified in the present study. © 2016 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Compilation of a near-infrared library for the construction of quantitative models of amoxicillin and potassium clavulanate oral dosage forms

NASA Astrophysics Data System (ADS)

Zou, Wen-bo; Chong, Xiao-meng; Wang, Yan; Hu, Chang-qin

2018-05-01

The accuracy of NIR quantitative models depends on calibration samples with concentration variability. Conventional sample collecting methods have some shortcomings especially the time-consuming which remains a bottleneck in the application of NIR models for Process Analytical Technology (PAT) control. A study was performed to solve the problem of sample selection collection for construction of NIR quantitative models. Amoxicillin and potassium clavulanate oral dosage forms were used as examples. The aim was to find a normal approach to rapidly construct NIR quantitative models using an NIR spectral library based on the idea of a universal model [2021]. The NIR spectral library of amoxicillin and potassium clavulanate oral dosage forms was defined and consisted of spectra of 377 batches of samples produced by 26 domestic pharmaceutical companies, including tablets, dispersible tablets, chewable tablets, oral suspensions, and granules. The correlation coefficient (rT) was used to indicate the similarities of the spectra. The samples’ calibration sets were selected from a spectral library according to the median rT of the samples to be analyzed. The rT of the samples selected was close to the median rT. The difference in rT of those samples was 1.0% to 1.5%. We concluded that sample selection is not a problem when constructing NIR quantitative models using a spectral library versus conventional methods of determining universal models. The sample spectra with a suitable concentration range in the NIR models were collected quickly. In addition, the models constructed through this method were more easily targeted.

Construction, Characterization, and Preliminary BAC-End Sequence Analysis of a Bacterial Artificial Chromosome Library of the Tea Plant (Camellia sinensis)

PubMed Central

Lin, Jinke; Kudrna, Dave; Wing, Rod A.

2011-01-01

We describe the construction and characterization of a publicly available BAC library for the tea plant, Camellia sinensis. Using modified methods, the library was constructed with the aim of developing public molecular resources to advance tea plant genomics research. The library consists of a total of 401,280 clones with an average insert size of 135 kb, providing an approximate coverage of 13.5 haploid genome equivalents. No empty vector clones were observed in a random sampling of 576 BAC clones. Further analysis of 182 BAC-end sequences from randomly selected clones revealed a GC content of 40.35% and low chloroplast and mitochondrial contamination. Repetitive sequence analyses indicated that LTR retrotransposons were the most predominant sequence class (86.93%–87.24%), followed by DNA retrotransposons (11.16%–11.69%). Additionally, we found 25 simple sequence repeats (SSRs) that could potentially be used as genetic markers. PMID:21234344

[cDNA library construction from panicle meristem of finger millet].

PubMed

Radchuk, V; Pirko, Ia V; Isaenkov, S V; Emets, A I; Blium, Ia B

2014-01-01

The protocol for production of full-size cDNA using SuperScript Full-Length cDNA Library Construction Kit II (Invitrogen) was tested and high quality cDNA library from meristematic tissue of finger millet panicle (Eleusine coracana (L.) Gaertn) was created. The titer of obtained cDNA library comprised 3.01 x 10(5) CFU/ml in avarage. In average the length of cDNA insertion consisted about 1070 base pairs, the effectivity of cDNA fragment insertions--99.5%. The selective sequencing of cDNA clones from created library was performed. The sequences of cDNA clones were identified with usage of BLAST-search. The results of cDNA library analysis and selective sequencing represents prove good functionality and full length character of inserted cDNA clones. Obtained cDNA library from meristematic tissue of finger millet panicle represents good and valuable source for isolation and identification of key genes regulating metabolism and meristematic development and for mining of new molecular markers to conduct out high quality genetic investigations and molecular breeding as well.

Flexible CRISPR library construction using parallel oligonucleotide retrieval

PubMed Central

Read, Abigail; Gao, Shaojian; Batchelor, Eric

2017-01-01

Abstract CRISPR/Cas9-based gene knockout libraries have emerged as a powerful tool for functional screens. We present here a set of pre-designed human and mouse sgRNA sequences that are optimized for both high on-target potency and low off-target effect. To maximize the chance of target gene inactivation, sgRNAs were curated to target both 5΄ constitutive exons and exons that encode conserved protein domains. We describe here a robust and cost-effective method to construct multiple small sized CRISPR library from a single oligo pool generated by array synthesis using parallel oligonucleotide retrieval. Together, these resources provide a convenient means for individual labs to generate customized CRISPR libraries of variable size and coverage depth for functional genomics application. PMID:28334828

Compositional Bias in Naïve and Chemically-modified Phage-Displayed Libraries uncovered by Paired-end Deep Sequencing.

PubMed

He, Bifang; Tjhung, Katrina F; Bennett, Nicholas J; Chou, Ying; Rau, Andrea; Huang, Jian; Derda, Ratmir

2018-01-19

Understanding the composition of a genetically-encoded (GE) library is instrumental to the success of ligand discovery. In this manuscript, we investigate the bias in GE-libraries of linear, macrocyclic and chemically post-translationally modified (cPTM) tetrapeptides displayed on the M13KE platform, which are produced via trinucleotide cassette synthesis (19 codons) and NNK-randomized codon. Differential enrichment of synthetic DNA {S}, ligated vector {L} (extension and ligation of synthetic DNA into the vector), naïve libraries {N} (transformation of the ligated vector into the bacteria followed by expression of the library for 4.5 hours to yield a "naïve" library), and libraries chemically modified by aldehyde ligation and cysteine macrocyclization {M} characterized by paired-end deep sequencing, detected a significant drop in diversity in {L} → {N}, but only a minor compositional difference in {S} → {L} and {N} → {M}. Libraries expressed at the N-terminus of phage protein pIII censored positively charged amino acids Arg and Lys; libraries expressed between pIII domains N1 and N2 overcame Arg/Lys-censorship but introduced new bias towards Gly and Ser. Interrogation of biases arising from cPTM by aldehyde ligation and cysteine macrocyclization unveiled censorship of sequences with Ser/Phe. Analogous analysis can be used to explore library diversity in new display platforms and optimize cPTM of these libraries.

The library system of the DFVLR: Present status, planned reorganization, user possibilities

NASA Technical Reports Server (NTRS)

Sternemann, P.

1985-01-01

This paper gives an overview of the present status, planned alterations, and the scope of users of the DFVLR library, as well as a survey of library related activities outside of the library department. Attention is given to the tasks of the DFVLR which include research, assistance in planning and carrying out projects, and the construction and operation of large test installations, showing how they relate to demands on the library.

Sorghum Expressed Sequence Tags Identify Signature Genes for Drought, Pathogenesis, and Skotomorphogenesis from a Milestone Set of 16,801 Unique Transcripts1[w

PubMed Central

Pratt, Lee H.; Liang, Chun; Shah, Manish; Sun, Feng; Wang, Haiming; Reid, St. Patrick; Gingle, Alan R.; Paterson, Andrew H.; Wing, Rod; Dean, Ralph; Klein, Robert; Nguyen, Henry T.; Ma, Hong-mei; Zhao, Xin; Morishige, Daryl T.; Mullet, John E.; Cordonnier-Pratt, Marie-Michèle

2005-01-01

Improved knowledge of the sorghum transcriptome will enhance basic understanding of how plants respond to stresses and serve as a source of genes of value to agriculture. Toward this goal, Sorghum bicolor L. Moench cDNA libraries were prepared from light- and dark-grown seedlings, drought-stressed plants, Colletotrichum-infected seedlings and plants, ovaries, embryos, and immature panicles. Other libraries were prepared with meristems from Sorghum propinquum (Kunth) Hitchc. that had been photoperiodically induced to flower, and with rhizomes from S. propinquum and johnsongrass (Sorghum halepense L. Pers.). A total of 117,682 expressed sequence tags (ESTs) were obtained representing both 3′ and 5′ sequences from about half that number of cDNA clones. A total of 16,801 unique transcripts, representing tentative UniScripts (TUs), were identified from 55,783 3′ ESTs. Of these TUs, 9,032 are represented by two or more ESTs. Collectively, these libraries were predicted to contain a total of approximately 31,000 TUs. Individual libraries, however, were predicted to contain no more than about 6,000 to 9,000, with the exception of light-grown seedlings, which yielded an estimate of close to 13,000. In addition, each library exhibits about the same level of complexity with respect to both the number of TUs preferentially expressed in that library and the frequency with which two or more ESTs is found in only that library. These results indicate that the sorghum genome is expressed in highly selective fashion in the individual organs and in response to the environmental conditions surveyed here. Close to 2,000 differentially expressed TUs were identified among the cDNA libraries examined, of which 775 were differentially expressed at a confidence level of 98%. From these 775 TUs, signature genes were identified defining drought, Colletotrichum infection, skotomorphogenesis (etiolation), ovary, immature panicle, and embryo. PMID:16169961

Identification of floral genes for sex determination in Calamus palustris Griff. by using suppression subtractive hybridization.

PubMed

Ng, C Y; Wickneswari, R; Choong, C Y

2014-08-07

Calamus palustris Griff. is an economically important dioecious rattan species in Southeast Asia. However, dioecy and onset of flowering at 3-4 years old render uncertainties in desired female:male seedling ratios to establish a productive seed orchard for this rattan species. We constructed a subtractive library for male floral tissue to understand the genetic mechanism for gender determination in C. palustris. The subtractive library produced 1536 clones with 1419 clones of high quality. Reverse Northern screening showed 313 clones with differential expression, and sequence analyses clustered them into 205 unigenes, including 32 contigs and 173 singletons. The subtractive library was further validated with reverse transcription-quantitative polymerase chain reaction analysis. Homology identification classified the unigenes into 12 putative functional proteins with 83% unigenes showing significant match to proteins in databases. Functional annotations of these unigenes revealed genes involved in male flower development, including MADS-box genes, pollen-related genes, phytohormones for flower development, and male flower organ development. Our results showed that the male floral genes may play a vital role in sex determination in C. palustris. The identified genes can be exploited to understand the molecular basis of sex determination in C. palustris.

Ouachita Parish Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program, 1992-1993.

ERIC Educational Resources Information Center

Camp, Gloria S.

The Ouachita Parish Public Library (Louisiana) conducted a project that involved recruitment, coalition building, public awareness, training, basic literacy, collection development, tutoring, technology, and English as a Second Language (ESL) programs. The project served a community of over 200,000 people, and targeted the learning disabled,…

Broward County Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Hansen, Janet

This final performance report for the Broward County Library New Reader Services Coordinator literacy project begins with a section that provides quantitative data. The next section compares actual accomplishments to the project objectives for 1992-93, including the hiring of a new reader as coordinator for the project and the establishment of…

Loudoun County Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Holtslander, Linda

This final performance report for the Loudoun County Public Library literacy project begins with a section that provides quantitative data. The next section compares actual accomplishments to the major project objective: to create a non-threatening learning environment at the Transitional Housing Center (THC), a residential homeless shelter.…

Chandler Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Drake, Karen; Rodriguez, Leonard

This final performance report for the Chandler Public Library literacy project for fiscal year 1992 begins with a section that provides quantitative data. The next section compares actual accomplishments to the project goal--to improve the quality of life for illiterate, semiliterate, and non-English-speaking citizens by providing a comprehensive…

The Management Review and Analysis Program: An Assisted Self-Study to Secure Constructive Change in the Management of Research Libraries

ERIC Educational Resources Information Center

Webster, Duane E.

1974-01-01

The Management Review and Analysis Program, an assisted self-study strategy for large academic and research libraries, assists libraries in reviewing and analyzing their current management policies and practices, and provides guidelines for the application of contemporary principles of management for the improvement of library programs. (Author/LS)

Identification and computational annotation of genes differentially expressed in pulp development of Cocos nucifera L. by suppression subtractive hybridization

PubMed Central

2014-01-01

Background Coconut (Cocos nucifera L.) is one of the world’s most versatile, economically important tropical crops. Little is known about the physiological and molecular basis of coconut pulp (endosperm) development and only a few coconut genes and gene product sequences are available in public databases. This study identified genes that were differentially expressed during development of coconut pulp and functionally annotated these identified genes using bioinformatics analysis. Results Pulp from three different coconut developmental stages was collected. Four suppression subtractive hybridization (SSH) libraries were constructed (forward and reverse libraries A and B between stages 1 and 2, and C and D between stages 2 and 3), and identified sequences were computationally annotated using Blast2GO software. A total of 1272 clones were obtained for analysis from four SSH libraries with 63% showing similarity to known proteins. Pairwise comparing of stage-specific gene ontology ids from libraries B-D, A-C, B-C and A-D showed that 32 genes were continuously upregulated and seven downregulated; 28 were transiently upregulated and 23 downregulated. KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis showed that 1-acyl-sn-glycerol-3-phosphate acyltransferase (LPAAT), phospholipase D, acetyl-CoA carboxylase carboxyltransferase beta subunit, 3-hydroxyisobutyryl-CoA hydrolase-like and pyruvate dehydrogenase E1 β subunit were associated with fatty acid biosynthesis or metabolism. Triose phosphate isomerase, cellulose synthase and glucan 1,3-β-glucosidase were related to carbohydrate metabolism, and phosphoenolpyruvate carboxylase was related to both fatty acid and carbohydrate metabolism. Of 737 unigenes, 103 encoded enzymes were involved in fatty acid and carbohydrate biosynthesis and metabolism, and a number of transcription factors and other interesting genes with stage-specific expression were confirmed by real-time PCR, with validation of the SSH results as high as 66.6%. Based on determination of coconut endosperm fatty acids content by gas chromatography–mass spectrometry, a number of candidate genes in fatty acid anabolism were selected for further study. Conclusion Functional annotation of genes differentially expressed in coconut pulp development helped determine the molecular basis of coconut endosperm development. The SSH method identified genes related to fatty acids, carbohydrate and secondary metabolites. The results will be important for understanding gene functions and regulatory networks in coconut fruit. PMID:25084812

Identification and computational annotation of genes differentially expressed in pulp development of Cocos nucifera L. by suppression subtractive hybridization.

PubMed

Liang, Yuanxue; Yuan, Yijun; Liu, Tao; Mao, Wei; Zheng, Yusheng; Li, Dongdong

2014-08-02

Coconut (Cocos nucifera L.) is one of the world's most versatile, economically important tropical crops. Little is known about the physiological and molecular basis of coconut pulp (endosperm) development and only a few coconut genes and gene product sequences are available in public databases. This study identified genes that were differentially expressed during development of coconut pulp and functionally annotated these identified genes using bioinformatics analysis. Pulp from three different coconut developmental stages was collected. Four suppression subtractive hybridization (SSH) libraries were constructed (forward and reverse libraries A and B between stages 1 and 2, and C and D between stages 2 and 3), and identified sequences were computationally annotated using Blast2GO software. A total of 1272 clones were obtained for analysis from four SSH libraries with 63% showing similarity to known proteins. Pairwise comparing of stage-specific gene ontology ids from libraries B-D, A-C, B-C and A-D showed that 32 genes were continuously upregulated and seven downregulated; 28 were transiently upregulated and 23 downregulated. KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis showed that 1-acyl-sn-glycerol-3-phosphate acyltransferase (LPAAT), phospholipase D, acetyl-CoA carboxylase carboxyltransferase beta subunit, 3-hydroxyisobutyryl-CoA hydrolase-like and pyruvate dehydrogenase E1 β subunit were associated with fatty acid biosynthesis or metabolism. Triose phosphate isomerase, cellulose synthase and glucan 1,3-β-glucosidase were related to carbohydrate metabolism, and phosphoenolpyruvate carboxylase was related to both fatty acid and carbohydrate metabolism. Of 737 unigenes, 103 encoded enzymes were involved in fatty acid and carbohydrate biosynthesis and metabolism, and a number of transcription factors and other interesting genes with stage-specific expression were confirmed by real-time PCR, with validation of the SSH results as high as 66.6%. Based on determination of coconut endosperm fatty acids content by gas chromatography-mass spectrometry, a number of candidate genes in fatty acid anabolism were selected for further study. Functional annotation of genes differentially expressed in coconut pulp development helped determine the molecular basis of coconut endosperm development. The SSH method identified genes related to fatty acids, carbohydrate and secondary metabolites. The results will be important for understanding gene functions and regulatory networks in coconut fruit.

Construction of a Llama Bacterial Artificial Chromosome Library with Approximately 9-Fold Genome Equivalent Coverage

PubMed Central

Airmet, K. W.; Hinckley, J. D.; Tree, L. T.; Moss, M.; Blumell, S.; Ulicny, K.; Gustafson, A. K.; Weed, M.; Theodosis, R.; Lehnardt, M.; Genho, J.; Stevens, M. R.; Kooyman, D. L.

2012-01-01

The Ilama is an important agricultural livestock in much of South America. The llama is increasing in popularity in the United States as a companion animal. Little work has been done to improve llama production using modern technology. A paucity of information is available regarding the llama genome. We report the construction of a llama bacterial artificial chromosome (BAC) library of about 196,224 clones in the vector pECBAC1. Using flow cytometry and bovine, human, mouse, and chicken as controls, we determined the llama genome size to be 2.4 × 109 bp. The average insert size of the library is 137.8 kb corresponding to approximately 9-fold genome coverage. Further studies are needed to further characterize the library and llama genome. We anticipate that this new library will help facilitate future genomic studies in the llama. PMID:22811594

[Construction of large fragment metagenome library of natural mangrove soil].

PubMed

Jiang, Yun-Xia; Zheng, Tian-Ling

2007-11-01

Applying our optimized direct extraction method, the percentage of large fragment DNA in the total extracted mangrove soil DNA was significant increased. The large fragment metagenome library derived from natural mangrove soil over four seasons was successfully constructed by the optimized DNA extraction and electro elution purification method. All of the clones had recombinant Cosmids and each differed in their fragment profiles when Cosmid DNA was extracted from 12 randomly picked colonies and digested with BamHI. The average insert size for this library was larger than 35 kbp. This culturing-independent library at least encompassed 335 Mbp valuable genetic information of mangrove soil microbes. It allowed mining of valuable intertidal microbial resource to become a reality. It is a recommended method for those researchers who have still not circumvented the large insert environmental libraries or for those beginning research in this field, so as to avoid them attempting repetitive, fussy work.

Construction of a cDNA library for miniature pig mandibular deciduous molars

PubMed Central

2014-01-01

Background The miniature pig provides an excellent experimental model for tooth morphogenesis because its diphyodont and heterodont dentition resembles that of humans. However, little information is available on the process of tooth development or the exact molecular mechanisms controlling tooth development in miniature pigs or humans. Thus, the analysis of gene expression related to each stage of tooth development is very important. Results In our study, after serial sections were made, the development of the crown of the miniature pigs’ mandibular deciduous molar could be divided into five main phases: dental lamina stage (E33-E35), bud stage (E35-E40), cap stage (E40-E50), early bell stage (E50-E60), and late bell stage (E60-E65). Total RNA was isolated from the tooth germ of miniature pig embryos at E35, E45, E50, and E60, and a cDNA library was constructed. Then, we identified cDNA sequences on a large scale screen for cDNA profiles in the developing mandibular deciduous molars (E35, E45, E50, and E60) of miniature pigs using Illumina Solexa deep sequencing. Microarray assay was used to detect the expression of genes. Lastly, through Unigene sequence analysis and cDNA expression pattern analysis at E45 and E60, we found that 12 up-regulated and 15 down-regulated genes during the four periods are highly conserved genes homologous with known Homo sapiens genes. Furthermore, there were 6 down-regulated and 2 up-regulated genes in the miniature pig that were highly homologous to Homo sapiens genes compared with those in the mouse. Conclusion Our results not only identify the specific transcriptome and cDNA profile in developing mandibular deciduous molars of the miniature pig, but also provide useful information for investigating the molecular mechanism of tooth development in the miniature pig. PMID:24750690

Construction of a cDNA library and preliminary analysis of expressed sequence tags in Piper hainanense.

PubMed

Fan, R; Ling, P; Hao, C Y; Li, F P; Huang, L F; Wu, B D; Wu, H S

2015-10-19

Black pepper is a perennial climbing vine. It is widely cultivated because its berries can be utilized not only as a spice in food but also for medicinal use. This study aimed to construct a standardized, high-quality cDNA library to facilitated identification of new Piper hainanense transcripts. For this, 262 unigenes were used to generate raw reads. The average length of these 262 unigenes was 774.8 bp. Of these, 94 genes (35.9%) were newly identified, according to the NCBI protein database. Thus, identification of new genes may broaden the molecular knowledge of P. hainanense on the basis of Clusters of Orthologous Groups and Gene Ontology categories. In addition, certain basic genes linked to physiological processes, which can contribute to disease resistance and thereby to the breeding of black pepper. A total of 26 unigenes were found to be SSR markers. Dinucleotide SSR was the main repeat motif, accounting for 61.54%, followed by trinucleotide SSR (23.07%). Eight primer pairs successfully amplified DNA fragments and detected significant amounts of polymorphism among twenty-one piper germplasm. These results present a novel sequence information of P. hainanense, which can serve as the foundation for further genetic research on this species.

Bioproduction and characterization of extracellular melanin-like pigment from industrially polluted metagenomic library equipped Escherichia coli.

PubMed

Amin, Shivani; Rastogi, Rajesh P; Sonani, Ravi R; Ray, Arabinda; Sharma, Rakesh; Madamwar, Datta

2018-04-15

To explore the potential genes from the industrially polluted Amlakhadi canal, located in Ankleshwar, Gujarat, India, its community genome was extracted and cloned into E. coli EPI300™-T1 R using a fosmid vector (pCC2 FOS™) generating a library of 3,92,000 clones with average size of 40kb of DNA-insert. From this library, the clone DM1 producing brown colored melanin-like pigment was isolated and characterized. For over expression of the pigment, further sub-cloning of the clone DM1 was done. Sub-clone containing 10kb of the insert was sequenced for gene identification. The amino acids sequence of a protein 4-Hydroxyphenylpyruvate dioxygenase (HPPD), which is know to be involved in melanin biosynthesis was obtained from the gene sequence. The sequence-homology based 3D structure model of HPPD was constructed and analyzed. The physico-chemical nature of pigment was further analysed using 1 H and 13 C NMR, LC-MS, FTIR and UV-visible spectroscopy. The pigment was readily soluble in DMSO with an absorption maximum around 290nm. Based on the genetic and chemical characterization, the compound was confirmed as melanin-like pigment. The present results indicate that the metagenomic library from industrially polluted environment generated a microbial tool for the production of melanin-like pigment. Copyright © 2018 Elsevier B.V. All rights reserved.

Transcriptome Analysis of the Scleractinian Coral Stylophora pistillata

PubMed Central

Salmon-Divon, Mali; Katzenellenbogen, Mark; Tambutté, Sylvie; Bertucci, Anthony; Hoegh-Guldberg, Ove; Deleury, Emeline; Allemand, Denis; Levy, Oren

2014-01-01

The principal architects of coral reefs are the scleractinian corals; these species are divided in two major clades referred to as “robust” and “complex” corals. Although the molecular diversity of the “complex” clade has received considerable attention, with several expressed sequence tag (EST) libraries and a complete genome sequence having been constructed, the “robust” corals have received far less attention, despite the fact that robust corals have been prominent focal points for ecological and physiological studies. Filling this gap affords important opportunities to extend these studies and to improve our understanding of the differences between the two major clades. Here, we present an EST library from Stylophora pistillata (Esper 1797) and systematically analyze the assembled transcripts compared to putative homologs from the complete proteomes of six well-characterized metazoans: Nematostella vectensis, Hydra magnipapillata, Caenorhabditis elegans, Drosophila melanogaster, Strongylocentrotus purpuratus, Ciona intestinalis and Homo sapiens. Furthermore, comparative analyses of the Stylophora pistillata ESTs were performed against several Cnidaria from the Scleractinia, Actiniaria and Hydrozoa, as well as against other stony corals separately. Functional characterization of S. pistillata transcripts into KOG/COG categories and further description of Wnt and bone morphogenetic protein (BMP) signaling pathways showed that the assembled EST library provides sufficient data and coverage. These features of this new library suggest considerable opportunities for extending our understanding of the molecular and physiological behavior of “robust” corals. PMID:24551124

Production of Recombinant Human scFv Against Tetanus Toxin Heavy Chain by Phage Display Technology.

PubMed

Khalili, Ehsan; Lakzaei, Mostafa; Rasaee, Mohhamad Javad; Aminian, Mahdi

2015-10-01

Tetanus, as a major cause of death in developing countries, is caused by tetanus neurotoxin. Recombinant antibodies against tetanus neurotoxin can be useful in tetanus management. Phage display of antibody fragments from immune human antibody libraries with single chain constructs combining the variable fragments (scFv) has been one of the most prominent technologies in antibody engineering. The aim of this study was the generation of a single chain fragment of variable region (scFv) library and selection of specific antibodies with high affinity against tetanus toxin. Immune human single chain fragment variable (HuscFv) antibody phagemid library was displayed on pIII of filamentous bacteriophage. Selection of scFv clones was performed against tetanus toxin antigens after three rounds of panning. The selected scFv clones were analyzed for inhibition of tetanus toxin binding to ganglioside GT1b. After the third round of panning, over 35 HuscFv phages specific for tetanus toxin were isolated from this library of which 15 clones were found to bind specifically to tetanus toxin. The selected HuscFv phages expressed as a soluble HuscFv peptide and some clones showed positive signals against tetanus toxin. We found that six HuscFv clones inhibit toxin binding to ganglioside GT1b. These selected antibodies can be used in the management of tetanus.

Library Systems: Current Developments and Future Directions.

ERIC Educational Resources Information Center

Healy, Leigh Watson

This report was commissioned in response to concerns expressed about the gap between institutional digital library initiatives and the products offered by library systems vendors. The study analyzes from the perspective of libraries the strategies, visions, and products that vendors of integrated library systems are offering as solutions. Case…

Molecular Toolkit for Gene Expression Control and Genome Modification in Rhodococcus opacus PD630

DOE PAGES

DeLorenzo, Drew M.; Rottinghaus, Austin G.; Henson, William R.; ...

2018-01-24

Rhodococcus opacus PD630 is a non-model, gram-positive bacterium that possesses desirable traits for lignocellulosic biomass conversion. In particular, it has a relatively rapid growth rate, exhibits genetic tractability, produces high quantities of lipids, and can tolerate and consume toxic, lignin-derived aromatic compounds. Despite these unique, industrially relevant characteristics, R. opacus has been underutilized due to a lack of reliable genetic parts and engineering tools. In this work, we developed a molecular toolbox for reliable gene expression control and genome modification in R. opacus. To facilitate predictable gene expression, a constitutive promoter library spanning ~45-fold in output was constructed. To improvemore » the characterization of available plasmids, the copy numbers of four heterologous and nine endogenous plasmids were determined using quantitative PCR. The molecular toolbox was further expanded by screening a previously unreported antibiotic resistance marker (HygR) and constructing a curable plasmid backbone for temporary gene expression (pB264). Furthermore, a system for genome modification was devised, and three neutral integration sites were identified using a novel combination of transcriptomic data, genomic architecture, and growth rate analysis. Finally, the first reported system for targeted, tunable gene repression in Rhodococcus was developed by utilizing CRISPR interference (CRISPRi). Overall, this work greatly expands the ability to manipulate and engineer R. opacus, making it a viable new chassis for bioproduction from renewable feedstocks.« less

Molecular Toolkit for Gene Expression Control and Genome Modification in Rhodococcus opacus PD630

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeLorenzo, Drew M.; Rottinghaus, Austin G.; Henson, William R.

Rhodococcus opacus PD630 is a non-model, gram-positive bacterium that possesses desirable traits for lignocellulosic biomass conversion. In particular, it has a relatively rapid growth rate, exhibits genetic tractability, produces high quantities of lipids, and can tolerate and consume toxic, lignin-derived aromatic compounds. Despite these unique, industrially relevant characteristics, R. opacus has been underutilized due to a lack of reliable genetic parts and engineering tools. In this work, we developed a molecular toolbox for reliable gene expression control and genome modification in R. opacus. To facilitate predictable gene expression, a constitutive promoter library spanning ~45-fold in output was constructed. To improvemore » the characterization of available plasmids, the copy numbers of four heterologous and nine endogenous plasmids were determined using quantitative PCR. The molecular toolbox was further expanded by screening a previously unreported antibiotic resistance marker (HygR) and constructing a curable plasmid backbone for temporary gene expression (pB264). Furthermore, a system for genome modification was devised, and three neutral integration sites were identified using a novel combination of transcriptomic data, genomic architecture, and growth rate analysis. Finally, the first reported system for targeted, tunable gene repression in Rhodococcus was developed by utilizing CRISPR interference (CRISPRi). Overall, this work greatly expands the ability to manipulate and engineer R. opacus, making it a viable new chassis for bioproduction from renewable feedstocks.« less

Translational initiation in Leishmania tarentolae and Phytomonas serpens (Kinetoplastida) is strongly influenced by pre-ATG triplet and its 5' sequence context.

PubMed

Lukes, Julius; Paris, Zdenek; Regmi, Sandesh; Breitling, Reinhard; Mureev, Sergey; Kushnir, Susanna; Pyatkov, Konstantin; Jirků, Milan; Alexandrov, Kirill A

2006-08-01

To investigate the influence of sequence context of translation initiation codon on translation efficiency in Kinetoplastida, we constructed a library of expression plasmids randomized in the three nucleotides prefacing ATG of a reporter gene encoding enhanced green fluorescent protein (EGFP). All 64 possible combinations of pre-ATG triplets were individually stably integrated into the rDNA locus of Leishmania tarentolae and the resulting cell lines were assessed for EGFP expression. The expression levels were quantified directly by measuring the fluorescence of EGFP protein in living cells and confirmed by Western blotting. We observed a strong influence of the pre-ATG triplet on the level of protein expression over a 20-fold range. To understand the degree of evolutionary conservation of the observed effect, we transformed Phytomonas serpens, a trypanosomatid parasite of plants, with a subset of the constructs. The pattern of translational efficiency mediated by individual pre-ATG triplets in this species was similar to that observed in L. tarentolae. However, the pattern of translational efficiency of two other proteins (red fluorescent protein and tetracycline repressor) containing selected pre-ATG triplets did not correlate with either EGFP or each other. Thus, we conclude that a conserved mechanism of translation initiation site selection exists in kinetoplastids that is strongly influenced not only by the pre-ATG sequences but also by the coding region of the gene.

Annual Program, 1987. Texas State Library.

ERIC Educational Resources Information Center

Texas State Library, Austin.

This report provides information related to the Texas State Library's fiscal year 1987 Library Services and Construction Act (LSCA) Public Law 84-597, as amended state-administered program. Information is included on: (1) Standard Form 424 for federal assistance; (2) fiscal breakdowns of estimated expenditures; (3) specific requirements for…

Georgia Public Library Statistics, 1975.

ERIC Educational Resources Information Center

Georgia State Dept of Education, Atlanta. Div. of Public Library Services.

Statistical data on Georgia public libraries are provided in tables covering regional and large county library systems, audiovisual materials, audiovisual expenditures, analysis of federal funds received, and Title II construction. Data on the services of the state agency are given for technical services, reader services, large group loans, state…

Carbohydrate active enzymes revealed in Coptotermes formosanus transcriptome

USDA-ARS?s Scientific Manuscript database

A normalized cDNA library of Coptotermes formosanus was constructed using mixed RNA isolated from workers, soldiers, nymphs and alates of both sexes. Sequencing of this library generated 131,637 EST and 25,939 unigenes were assembled. Carbohydrate active enzymes (CAZymes) revealed in this library we...

Determination of a Screening Metric for High Diversity DNA Libraries.

PubMed

Guido, Nicholas J; Handerson, Steven; Joseph, Elaine M; Leake, Devin; Kung, Li A

2016-01-01

The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

Porcine transcriptome analysis based on 97 non-normalized cDNA libraries and assembly of 1,021,891 expressed sequence tags

PubMed Central

Gorodkin, Jan; Cirera, Susanna; Hedegaard, Jakob; Gilchrist, Michael J; Panitz, Frank; Jørgensen, Claus; Scheibye-Knudsen, Karsten; Arvin, Troels; Lumholdt, Steen; Sawera, Milena; Green, Trine; Nielsen, Bente J; Havgaard, Jakob H; Rosenkilde, Carina; Wang, Jun; Li, Heng; Li, Ruiqiang; Liu, Bin; Hu, Songnian; Dong, Wei; Li, Wei; Yu, Jun; Wang, Jian; Stærfeldt, Hans-Henrik; Wernersson, Rasmus; Madsen, Lone B; Thomsen, Bo; Hornshøj, Henrik; Bujie, Zhan; Wang, Xuegang; Wang, Xuefei; Bolund, Lars; Brunak, Søren; Yang, Huanming; Bendixen, Christian; Fredholm, Merete

2007-01-01

Background Knowledge of the structure of gene expression is essential for mammalian transcriptomics research. We analyzed a collection of more than one million porcine expressed sequence tags (ESTs), of which two-thirds were generated in the Sino-Danish Pig Genome Project and one-third are from public databases. The Sino-Danish ESTs were generated from one normalized and 97 non-normalized cDNA libraries representing 35 different tissues and three developmental stages. Results Using the Distiller package, the ESTs were assembled to roughly 48,000 contigs and 73,000 singletons, of which approximately 25% have a high confidence match to UniProt. Approximately 6,000 new porcine gene clusters were identified. Expression analysis based on the non-normalized libraries resulted in the following findings. The distribution of cluster sizes is scaling invariant. Brain and testes are among the tissues with the greatest number of different expressed genes, whereas tissues with more specialized function, such as developing liver, have fewer expressed genes. There are at least 65 high confidence housekeeping gene candidates and 876 cDNA library-specific gene candidates. We identified differential expression of genes between different tissues, in particular brain/spinal cord, and found patterns of correlation between genes that share expression in pairs of libraries. Finally, there was remarkable agreement in expression between specialized tissues according to Gene Ontology categories. Conclusion This EST collection, the largest to date in pig, represents an essential resource for annotation, comparative genomics, assembly of the pig genome sequence, and further porcine transcription studies. PMID:17407547

Identification of essential genes and synthetic lethal gene combinations in Escherichia coli K-12.

PubMed

Mori, Hirotada; Baba, Tomoya; Yokoyama, Katsushi; Takeuchi, Rikiya; Nomura, Wataru; Makishi, Kazuichi; Otsuka, Yuta; Dose, Hitomi; Wanner, Barry L

2015-01-01

Here we describe the systematic identification of single genes and gene pairs, whose knockout causes lethality in Escherichia coli K-12. During construction of precise single-gene knockout library of E. coli K-12, we identified 328 essential gene candidates for growth in complex (LB) medium. Upon establishment of the Keio single-gene deletion library, we undertook the development of the ASKA single-gene deletion library carrying a different antibiotic resistance. In addition, we developed tools for identification of synthetic lethal gene combinations by systematic construction of double-gene knockout mutants. We introduce these methods herein.

Generation of human Fab antibody libraries: PCR amplification and assembly of light- and heavy-chain coding sequences.

PubMed

Andris-Widhopf, Jennifer; Steinberger, Peter; Fuller, Roberta; Rader, Christoph; Barbas, Carlos F

2011-09-01

The development of therapeutic antibodies for use in the treatment of human diseases has long been a goal for many researchers in the antibody field. One way to obtain these antibodies is through phage-display libraries constructed from human lymphocytes. This protocol describes the construction of human Fab (fragment antigen binding) antibody libraries. In this method, the individual rearranged heavy- and light-chain variable regions are amplified separately and are linked through a series of overlap polymerase chain reaction (PCR) steps to give the final Fab products that are used for cloning.

A genome-wide expression profile of salt-responsive genes in the apple rootstock Malus zumi.

PubMed

Li, Qingtian; Liu, Jia; Tan, Dunxian; Allan, Andrew C; Jiang, Yuzhuang; Xu, Xuefeng; Han, Zhenhai; Kong, Jin

2013-10-18

In some areas of cultivation, a lack of salt tolerance severely affects plant productivity. Apple, Malus x domestica Borkh., is sensitive to salt, and, as a perennial woody plant the mechanism of salt stress adaption will be different from that of annual herbal model plants, such as Arabidopsis. Malus zumi is a salt tolerant apple rootstock, which survives high salinity (up to 0.6% NaCl). To examine the mechanism underlying this tolerance, a genome-wide expression analysis was performed, using a cDNA library constructed from salt-treated seedlings of Malus zumi. A total of 15,000 cDNA clones were selected for microarray analysis. In total a group of 576 cDNAs, of which expression changed more than four-fold, were sequenced and 18 genes were selected to verify their expression pattern under salt stress by semi-quantitative RT-PCR. Our genome-wide expression analysis resulted in the isolation of 50 novel Malus genes and the elucidation of a new apple-specific mechanism of salt tolerance, including the stabilization of photosynthesis under stress, involvement of phenolic compounds, and sorbitol in ROS scavenging and osmoprotection. The promoter regions of 111 genes were analyzed by PlantCARE, suggesting an intensive cross-talking of abiotic stress in Malus zumi. An interaction network of salt responsive genes was constructed and molecular regulatory pathways of apple were deduced. Our research will contribute to gene function analysis and further the understanding of salt-tolerance mechanisms in fruit trees.

A Genome-Wide Expression Profile of Salt-Responsive Genes in the Apple Rootstock Malus zumi

PubMed Central

Li, Qingtian; Liu, Jia; Tan, Dunxian; Allan, Andrew C.; Jiang, Yuzhuang; Xu, Xuefeng; Han, Zhenhai; Kong, Jin

2013-01-01

In some areas of cultivation, a lack of salt tolerance severely affects plant productivity. Apple, Malus x domestica Borkh., is sensitive to salt, and, as a perennial woody plant the mechanism of salt stress adaption will be different from that of annual herbal model plants, such as Arabidopsis. Malus zumi is a salt tolerant apple rootstock, which survives high salinity (up to 0.6% NaCl). To examine the mechanism underlying this tolerance, a genome-wide expression analysis was performed, using a cDNA library constructed from salt-treated seedlings of Malus zumi. A total of 15,000 cDNA clones were selected for microarray analysis. In total a group of 576 cDNAs, of which expression changed more than four-fold, were sequenced and 18 genes were selected to verify their expression pattern under salt stress by semi-quantitative RT-PCR. Our genome-wide expression analysis resulted in the isolation of 50 novel Malus genes and the elucidation of a new apple-specific mechanism of salt tolerance, including the stabilization of photosynthesis under stress, involvement of phenolic compounds, and sorbitol in ROS scavenging and osmoprotection. The promoter regions of 111 genes were analyzed by PlantCARE, suggesting an intensive cross-talking of abiotic stress in Malus zumi. An interaction network of salt responsive genes was constructed and molecular regulatory pathways of apple were deduced. Our research will contribute to gene function analysis and further the understanding of salt-tolerance mechanisms in fruit trees. PMID:24145753

The miiuy croaker microRNA transcriptome and microRNA regulation of RIG-I like receptor signaling pathway after poly(I:C) stimulation.

PubMed

Han, Jingjing; Xu, Guoliang; Xu, Tianjun

2016-07-01

MicroRNAs (miRNAs) as endogenous small non-coding RNAs play key regulatory roles in diverse biological processes via degrading the target mRNAs or inhibiting protein translation. Previously many researchers have reported the identification, characteristic of miRNAs and the interaction with its target gene. But, the study on the regulation of miRNAs to biological processes via regulatory the key signaling pathway was still limited. In order to comprehend the regulatory mechanism of miRNAs, two small RNA libraries from the spleen of miiuy croaker individuals with or without poly(I:C) infection were constructed. The 197 conserved miRNAs and 75 novel miRNAs were identified, and 14 conserved and 8 novel miRNAs appeared significant variations. Those differently expressed miRNAs relate to immune regulation of miiuy croaker. Furthermore, expressions of four differently expressed miRNAs were validated by qRT-PCR, and the result was consistent with sequencing data. The target genes of the differently expressed miRNAs in the two libraries were predicted, and some candidate target genes were involved in the RIG-I-like receptor (RLR) signaling pathway. The negative regulation of miRNAs to target genes were confirmed by comparing the expression pattern of miRNAs and their target genes. The results of regulating target genes were that firstly directly or indirectly activating the downstream signaling cascades and subsequent inducting the type I interferon, inflammatory cytokines and apoptosis. These studies could help us to deeper understand the roles of miRNAs played in the fish immune system, and provide a new way to investigate the defense mechanism of fish. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cloning and analysis of fetal ovary microRNAs in cattle.

PubMed

Tripurani, Swamy K; Xiao, Caide; Salem, Mohamed; Yao, Jianbo

2010-07-01

Ovarian folliculogenesis and early embryogenesis are complex processes, which require tightly regulated expression and interaction of a multitude of genes. Small endogenous RNA molecules, termed microRNAs (miRNAs), are involved in the regulation of gene expression during folliculogenesis and early embryonic development. To identify miRNAs in bovine oocytes/ovaries, a bovine fetal ovary miRNA library was constructed. Sequence analysis of random clones from the library identified 679 miRNA sequences, which represent 58 distinct bovine miRNAs. Of these distinct miRNAs, 42 are known bovine miRNAs present in the miRBase database and the remaining 16 miRNAs include 15 new bovine miRNAs that are homologous to miRNAs identified in other species, and one novel miRNA, which does not match any miRNAs in the database. The precursor sequences for 14 of the new 15 miRNAs as well as the novel miRNA were identified from the bovine genome database and their hairpin structures were predicted. Expression analysis of the 58 miRNAs in fetal ovaries in comparison to somatic tissue pools identified 8 miRNAs predominantly expressed in fetal ovaries. Further analysis of the eight miRNAs in germinal vesicle (GV) stage oocytes identified two miRNAs (bta-mir424 and bta-mir-10b), that are highly abundant in GV oocytes. Both miRNAs show similar expression patterns during oocyte maturation and preimplantation development of bovine embryos, being abundant in GV and MII stage oocytes, as well as in early stage embryos (until 16-cell stage). The amount of the novel miRNA is relatively small in oocytes and early cleavage embryos but greater in blastocysts, suggesting a role of this miRNA in blastocyst cell differentiation. Copyright 2010 Elsevier B.V. All rights reserved.

Transcriptome analysis of starch and sucrose metabolism across bulb development in Sagittaria sagittifolia.

PubMed

Gao, Meiping; Zhang, Shangwen; Luo, Cong; He, Xinhua; Wei, Shaolong; Jiang, Wen; He, Fanglian; Lin, Zhicheng; Yan, Meixin; Dong, Weiqong

2018-04-05

Sagittaria sagittifolia L is an important bulb vegetable that has high nutritional and medical value. Bulb formation and development are crucial to Sagittaria sagittifolia; however, its sucrose metabolism is poorly understood and there are a lack of sufficient transcriptomic and genomic data available to fully understand the molecular mechanisms underlying bulb formation and development as well as the bulb transcriptome. Five cDNA libraries were constructed at different developmental stages and sequenced using high-throughput Illumina RNA sequencing. From approximately 63.53 Gb clean reads, a total of 60,884 unigenes, with an average length of 897.34 bp and N50 of 1.368 kb, were obtained. A total of 36,590 unigenes were successfully annotated using five public databases. Across different developmental stages, 4195, 827, 832, 851, and 1494 were differentially expressed in T02, T03, T04, T05, and T06 libraries, respectively. Gene ontology (GO) analysis revealed several differentially-expressed genes (DEGs) associated with catalytic activity, binding, and transporter activity. The Kyoto encyclopedia of genes and genomes (KEGG) revealed that these DEGs are involved in physiological and biochemical processes. RT-qPCR was used to profile the expression of these unigenes and revealed that the expression patterns of the DEGs were consistent with the transcriptome data. In this study, we conducted a comparative gene expression analysis at the transcriptional level using RNA-seq across the different developmental stages of Sagittaria sagittifolia. We identified a set of genes that might contribute to starch and sucrose metabolism, and the genetic mechanisms related to bulblet development were also explored. This study provides important data for future studies of the genetic and molecular mechanisms underlying bulb formation and development in Sagittaria sagittifolia. Copyright © 2018. Published by Elsevier B.V.

Signatures from Tissue-specific MPSS Libraries Identify Transcripts Preferentially Expressed in the Mouse Inner Ear

PubMed Central

Peters, Linda M.; Belyantseva, Inna A.; Lagziel, Ayala; Battey, James F.; Friedman, Thomas B.; Morell, Robert J.

2007-01-01

Specialization in cell function and morphology is influenced by the differential expression of mRNAs, many of which are expressed at low abundance and restricted to certain cell types. Detecting such transcripts in cDNA libraries may require sequencing millions of clones. Massively parallel signature sequencing (MPSS) is well-suited for identifying transcripts that are expressed in discrete cell types and in low abundance. We have made MPSS libraries from microdissections of three inner ear tissues. By comparing these MPSS libraries to those of 87 other tissues included in the Mouse Reference Transcriptome (MRT) online resource, we have identified genes that are highly enriched in, or specific to, the inner ear. We show by RT-PCR and in situ hybridization that signatures unique to the inner ear libraries identify transcripts with highly specific cell-type localizations. These transcripts serve to illustrate the utility of a resource that is available to the research community. Utilization of these resources will increase the number of known transcription units and expand our knowledge of the tissue-specific regulation of the transcriptome. PMID:17049805

[Isolation and function of genes regulating aphB expression in Vibrio cholerae].

PubMed

Chen, Haili; Zhu, Zhaoqin; Zhong, Zengtao; Zhu, Jun; Kan, Biao

2012-02-04

We identified genes that regulate the expression of aphB, the gene encoding a key virulence regulator in Vibrio cholerae O1 E1 Tor C6706(-). We constructed a transposon library in V. cholerae C6706 strain containing a P(aphB)-luxCDABE and P(aphB)-lacZ transcriptional reporter plasmids. Using a chemiluminescence imager system, we rapidly detected aphB promoter expression level at a large scale. We then sequenced the transposon insertion sites by arbitrary PCR and sequencing analysis. We obtained two candidate mutants T1 and T2 which displayed reduced aphB expression from approximately 40,000 transposon insertion mutants. Sequencing analysis shows that Tn inserted in vc1585 reading frame in the T1 mutant and Tn inserted in the end of coding sequence of vc1602 in the T2 mutant. By using a genetic screen, we identified two potential genes that may involve in regulation of the expression of the key virulence regulator AphB. This study sheds light on our further investigation to fully understand V. cholerae virulence gene regulatory cascades.

An in vivo and in silico approach to study cis-antisense: a short cut to higher order response

NASA Astrophysics Data System (ADS)

Courtney, Colleen; Varanasi, Usha; Chatterjee, Anushree

2014-03-01

Antisense interactions are present in all domains of life. Typically sense, antisense RNA pairs originate from overlapping genes with convergent face to face promoters, and are speculated to be involved in gene regulation. Recent studies indicate the role of transcriptional interference (TI) in regulating expression of genes in convergent orientation. Modeling antisense, TI gene regulation mechanisms allows us to understand how organisms control gene expression. We present a modeling and experimental framework to understand convergent transcription that combines the effects of transcriptional interference and cis-antisense regulation. Our model shows that combining transcriptional interference and antisense RNA interaction adds multiple-levels of regulation which affords a highly tunable biological output, ranging from first order response to complex higher-order response. To study this system we created a library of experimental constructs with engineered TI and antisense interaction by using face-to-face inducible promoters separated by carefully tailored overlapping DNA sequences to control expression of a set of fluorescent reporter proteins. Studying this gene expression mechanism allows for an understanding of higher order behavior of gene expression networks.

Analysis of a diverse assemblage of diazotrophic bacteria from Spartina alterniflora using DGGE and clone library screening.

PubMed

Lovell, Charles R; Decker, Peter V; Bagwell, Christopher E; Thompson, Shelly; Matsui, George Y

2008-05-01

Methods to assess the diversity of the diazotroph assemblage in the rhizosphere of the salt marsh cordgrass, Spartina alterniflora were examined. The effectiveness of nifH PCR-denaturing gradient gel electrophoresis (DGGE) was compared to that of nifH clone library analysis. Seventeen DGGE gel bands were sequenced and yielded 58 nonidentical nifH sequences from a total of 67 sequences determined. A clone library constructed using the GC-clamp nifH primers that were employed in the PCR-DGGE (designated the GC-Library) yielded 83 nonidentical sequences from a total of 257 nifH sequences. A second library constructed using an alternate set of nifH primers (N-Library) yielded 83 nonidentical sequences from a total of 138 nifH sequences. Rarefaction curves for the libraries did not reach saturation, although the GC-Library curve was substantially dampened and appeared to be closer to saturation than the N-Library curve. Phylogenetic analyses showed that DGGE gel band sequencing recovered nifH sequences that were frequently sampled in the GC-Library, as well as sequences that were infrequently sampled, and provided a species composition assessment that was robust, efficient, and relatively inexpensive to obtain. Further, the DGGE method permits a large number of samples to be examined for differences in banding patterns, after which bands of interest can be sampled for sequence determination.

PAGE-1, an X chromosome-linked GAGE-like gene that is expressed in normal and neoplastic prostate, testis, and uterus

PubMed Central

Brinkmann, Ulrich; Vasmatzis, George; Lee, Byungkook; Yerushalmi, Noga; Essand, Magnus; Pastan, Ira

1998-01-01

We have used a combination of computerized database mining and experimental expression analyses to identify a gene that is preferentially expressed in normal male and female reproductive tissues, prostate, testis, fallopian tube, uterus, and placenta, as well as in prostate cancer, testicular cancer, and uterine cancer. This gene is located on the human X chromosome, and it is homologous to a family of genes encoding GAGE-like proteins. GAGE proteins are expressed in a variety of tumors and in testis. We designate the novel gene PAGE-1 because the expression pattern in the Cancer Genome Anatomy Project libraries indicates that it is predominantly expressed in normal and neoplastic prostate. Further database analysis indicates the presence of other genes with high homology to PAGE-1, which were found in cDNA libraries derived from testis, pooled libraries (with testis), and in a germ cell tumor library. The expression of PAGE-1 in normal and malignant prostate, testicular, and uterine tissues makes it a possible target for the diagnosis and possibly for the vaccine-based therapy of neoplasms of prostate, testis, and uterus. PMID:9724777

PAGE-1, an X chromosome-linked GAGE-like gene that is expressed in normal and neoplastic prostate, testis, and uterus.

PubMed

Brinkmann, U; Vasmatzis, G; Lee, B; Yerushalmi, N; Essand, M; Pastan, I

1998-09-01

We have used a combination of computerized database mining and experimental expression analyses to identify a gene that is preferentially expressed in normal male and female reproductive tissues, prostate, testis, fallopian tube, uterus, and placenta, as well as in prostate cancer, testicular cancer, and uterine cancer. This gene is located on the human X chromosome, and it is homologous to a family of genes encoding GAGE-like proteins. GAGE proteins are expressed in a variety of tumors and in testis. We designate the novel gene PAGE-1 because the expression pattern in the Cancer Genome Anatomy Project libraries indicates that it is predominantly expressed in normal and neoplastic prostate. Further database analysis indicates the presence of other genes with high homology to PAGE-1, which were found in cDNA libraries derived from testis, pooled libraries (with testis), and in a germ cell tumor library. The expression of PAGE-1 in normal and malignant prostate, testicular, and uterine tissues makes it a possible target for the diagnosis and possibly for the vaccine-based therapy of neoplasms of prostate, testis, and uterus.

Use of lambdagt11 to isolate genes for two pseudorabies virus glycoproteins with homology to herpes simplex virus and varicella-zoster virus glycoproteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petrovskis, E.A.; Timmins, J.G.; Post, L.E.

1986-10-01

A library of pseudorabies virus (PRV) DNA fragments was constructed in the expression cloning vector lambdagt11. The library was screened with antisera which reacted with mixtures of PRV proteins to isolate recombinant bacteriophages expressing PRV proteins. By the nature of the lambdagt11 vector, the cloned proteins were expressed in Escherichia coli as ..beta..-galactosidase fusion proteins. The fusion proteins from 35 of these phages were purified and injected into mice to raise antisera. The antisera were screened by several different assays, including immunoprecipitation of (/sup 14/C)glucosamine-labeled PRV proteins. This method identified phages expressing three different PRV glycoproteins: the secreted glycoprotein, gX;more » gI; and a glycoprotein that had not been previously identified, which we designate gp63. The gp63 and gI genes map adjacent to each other in the small unique region of the PRV genome. The DNA sequence was determined for the region of the genome encoding gp63 and gI. It was found that gp63 has a region of homology with a herpes simplex virus type 1 (HSV-1) protein, encoded by US7, and also with varicella-zoster virus (VZV) gpIV. The gI protein sequence has a region of homology with HSV-1 gE and VZV gpI. It is concluded that PRV, HSV, and VZV all have a cluster of homologous glycoprotein genes in the small unique components of their genomes and that the organization of these genes is conserved.« less

Genes differentially expressed in Theobroma cacao associated with resistance to witches' broom disease caused by Crinipellis perniciosa.

PubMed

Leal, Gildemberg Amorim; Albuquerque, Paulo S B; Figueira, Antonio

2007-05-01

SUMMARY The basidiomycete Crinipellis perniciosa is the causal agent of witches' broom disease of Theobroma cacao (cocoa). Hypertrophic growth of infected buds ('brooms') is the most dramatic symptom, but the main economic losses derive from pod infection. To identify cocoa genes differentially expressed during the early stages of infection, two cDNA libraries were constructed using the suppression subtractive hybridization (SSH) approach. Subtraction hybridization was conducted between cDNAs from infected shoot-tips of the susceptible genotype 'ICS 39' and the resistant 'CAB 214', in both directions. A total of 187 unique sequences were obtained, with 83 from the library enriched for the susceptible 'ICS 39' sequences, and 104 for the resistant 'CAB 214'. By homology search and ontology analyses, the identified sequences were mainly putatively categorized as belonging to 'signal transduction', 'response to biotic and abiotic stress', 'metabolism', 'RNA and DNA metabolism', 'protein metabolism' and 'cellular maintenance' classes. Quantitative reverse transcription amplification (RT-qPCR) of 23 transcripts identified as differentially expressed between genotypes revealed distinct kinetics of gene up-regulation at the asymptomatic stage of the disease. Expression induction in the susceptible 'ICS 39' in response to C. perniciosa was delayed and limited, while in 'CAB 214' there was a quicker and more intense reaction, with two peaks of gene induction at 48 and 120 h after inoculation, corresponding to morphological and biochemical changes previously described during colonization. Similar differences in gene induction were validated for another resistant genotype ('CAB 208') in an independent experiment. Validation of these genes corroborated similar hypothetical mechanisms of resistance described in other pathosystems.

Preservation Building Survey Form for Freestanding Library Unit.

ERIC Educational Resources Information Center

Huff, Susan M.

A modification of a University of Michigan form, this survey form is designed to obtain information on a freestanding library unit for preservation. The questionnaire covers the following areas: (1) library facility construction--e.g., primary building materials, characteristics of the foundation and roof, recent problems; (2) heating and cooling…

College Library Buildings in Transition--Looking at the 1980's.

ERIC Educational Resources Information Center

Snyder, Richard L.

This paper examines the likely effects of technological developments on the planning of American academic library buildings during the 1980's and shares Richard Snyder's experiences in the design and construction of a new library building at Drexel University in Pennsylvania. Descriptions of general, economic, policy, psychological, and…

By Our Own Bootstraps: Making Document Delivery Work in Oregon.

ERIC Educational Resources Information Center

Burkholder, Sue A.

1992-01-01

Describes the development of a courier service in Oregon for document delivery between libraries to support coordinated collection development activities. Organization of the service by individual libraries without dependence on the Library Services and Construction Act is discussed, and costs and response time are considered. (two references)…

Annual Report on LSCA Priorities, FY 1981.

ERIC Educational Resources Information Center

Neff, Evaline; And Others

This compilation results from efforts of the State and Public Library Services Branch of the U.S. Department of Education to disseminate pertinent information submitted by the State Library Administrative Agencies on key LSCA (Library Services and Construction Act) program areas. Each report was written by an administrative librarian who had key…

Managing the Library Fire Risk.

ERIC Educational Resources Information Center

Morris, John

A discussion of fire risks, causes, prevention, and salvage in libraries is presented in text and photographs. A description of some historic library fires demonstrates the value of adequate protection and preparedness programs to minimize loss and damage. The need for fire retardant construction and protection from valdalism and arson are…

Don't Take Marketing for "Grant"ed: Building Marketing Efforts into Library Grant Initiatives

ERIC Educational Resources Information Center

Germain, Carol Anne

2009-01-01

Libraries frequently apply for grants to help fund special projects and resources, such as purchases for library collections, innovative instructional technologies, and research subscription databases. Grants provide support for cultural events, professional development sessions, new construction, and building renovations. Like other library…

Literacy Is VITAL. Final Report.

ERIC Educational Resources Information Center

Gillfillan, Nancy M.

Via an LSCA (Library Services and Construction Act) Title VI Library Literacy grant for fiscal year 1986, the Dixon (Illinois) Public Library expanded its involvement in the literacy effort. Additional rooms were made available for tutoring, materials and equipment for literacy students and books and equipment for literacy tutors were provided,…

Global Warming's Library Challenge

ERIC Educational Resources Information Center

Meyer, Jennifer

2008-01-01

Like every institution that uses energy, consumes resources, and engages in construction or renovation, libraries have an impact on the environment and on the critical problem of climate change. Taking action to protect library collections is not only an idealistic professional goal but also a very practical one. Disaster preparation measures and…

Library Buildings 2009: The Constant Library

ERIC Educational Resources Information Center

Fox, Bette-Lee

2009-01-01

Can it be only two years, as Alan Jay Lerner once wrote, "since the whole [economic] rigmarole began"? Yet libraries have weathered to varying degrees the unreliability of funding, especially with regard to programming, materials, and hours. Money earmarked years ago is seeing construction through to conclusion; state support has helped out in…

Harlan County Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Warren, Carol E.

The Harlan County Public Library Literacy Project (Kentucky) provided rural-oriented, basic literacy, and oral history programs to a community of 100,000-200,000. The goal of the project was to produce six booklets about local people and issues, to be used as literacy materials in programs with Appalachian students. Students wanted to produce…

Teaching and Learning Spaces; Refurbishment of the W. K. Hancock Science Library at the Australian National University 2011

ERIC Educational Resources Information Center

McNamara, Paul

2012-01-01

Two floors of the W. K. Hancock Library at the Australian National University (ANU) were refurbished in 2011 as part of a cooperative project between the library and the College of Science. The refurbishment, costing $5 million, was part of a much larger exercise involving the construction of four new science buildings around the Hancock Library.…

Libraries of Middlesex, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Director, Elissa

This final performance report for the Libraries of Middlesex literacy project begins with a section that compares actual accomplishments to the following objectives for 1992-93: (1) recruit and enroll at least 150 new volunteers in Basic Reading of English as a Second Language (ESL) tutor training; (2) have at least 125 volunteers successfully…

Library Services and Construction Act Amendments of 1990. Conference Report (To Accompany H.R. 2742). House of Representatives, 101st Congress, 2nd Session.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC.

This conference report on the Library Services and Construction Act Amendments of 1990 includes the text of a substitute amendment agreed to by a committee of House of Representatives and Senate members. Amendments are presented for the following sections of the act: (1) Short Title; References; (2) Definitions; (3) Authorization of…

Cloning and expression of delta-1-pyrroline-5-carboxylate dehydrogenase in Escherichia coli DH5α improves phosphate solubilization.

PubMed

Gong, Mingbo; Tang, Chaoxi; Zhu, Changxiong

2014-11-01

A primary cDNA library of Penicillium oxalicum I1 was constructed using the switching mechanism at the 5' end of the RNA transcript (SMART) technique. A total of 106 clones showed halos in tricalcium phosphate (TCP) medium, and clone I-40 showed clear halos. The full-length cDNA of clone I-40 was 1355 bp with a complete open reading frame (ORF) of 1032 bp, encoding a protein of 343 amino acids. Multiple alignment analysis revealed a high degree of homology between the ORF of clone I-40 and delta-1-pyrroline-5-carboxylate dehydrogenase (P5CDH) of other fungi. The ORF expression vector was constructed and transformed into Escherichia coli DH5α. The transformant (ORF-1) with the P5CDH gene secreted organic acid in medium with TCP as the sole source of phosphate. Acetic acid and α-ketoglutarate were secreted in 4 and 24 h, respectively. ORF-1 decreased the pH of the medium from 6.62 to 3.45 and released soluble phosphate at 0.172 mg·mL(-1) in 28 h. Expression of the P. oxalicum I1 p5cdh gene in E. coli could enhance organic acid secretion and phosphate-solubilizing ability.

Expressed sequence tag (EST) analysis of the pine wood nematode Bursaphelenchus xylophilus and B. mucronatus.

PubMed

Kikuchi, Taisei; Aikawa, Takuya; Kosaka, Hajime; Pritchard, Leighton; Ogura, Nobuo; Jones, John T

2007-09-01

Most Bursaphelenchus species feed on fungi that colonise dead or dying trees. However, Bursaphelenchus xylophilus is unique in that in addition to feeding on fungi it has the capacity to be a parasite of live pine trees. We present an analysis of over 13,000 expressed sequence tags (ESTs) from B. xylophilus and, by way of contrast, over 3000 ESTs from a closely related species that does not parasitise plants as readily; B. mucronatus. Four libraries from B. xylophilus, from a variety of life stages including fungal feeding nematodes, nematodes extracted from plants and dauer-like stage nematodes, and one library from B. mucronatus were constructed and used to generate ESTs. Contig analysis showed that the 13,327 B. xylophilus ESTs could be grouped into 2110 contigs and 4377 singletons giving a total of 6487 identified genes. Similarly the 3193 B. mucronatus ESTs yielded a total of 2219 identified genes from 425 contigs and 1794 singletons. A variety of proteins potentially important in the parasitic process of B. xylophilus and B. mucronatus, including plant and fungal cell wall degrading enzymes and a novel gene potentially encoding a expansin-like protein that may disrupt non-covalent bonds in the plant cell wall were identified in the libraries. Additionally several gene candidates potentially involved in dauer entry or maintenance were also identified in the EST dataset. The EST sequences from this study will provide a solid base for future research on the biology, pathogenicity and evolutionary history of this nematode group.

Patron Behavior Policies in the Public Library: "Kreimer v. Morristown" Revisited.

ERIC Educational Resources Information Center

Geiszler, Robert W.

1998-01-01

The case of an indigent library patron recovering a judgment against a public library is used as a backdrop for discussing patron behavior policies in the public library. Highlights include First Amendment rights, the public library as an expressive forum, government rules, policy lessons from the case, and acceptable policies. (AEF)

[Construction of a phage antibody library and screening of anti-epidermal growth factor receptor variant III single chain antibody].

PubMed

Han, Dong-gang; Duan, Xiao-yi; Guo, You-min; Zhou, Qi; Wang, Quan-ying; Yang, Guang-xiao

2010-01-01

To obtain specific anti-epidermal growth factor receptor variant III (EGFRvIII) single chain antibody (ScFv) by phage antibody library display system. The total RNA was extracted from the spleen B cells of BALB/c mice immunized with pep-3-OVA protein, and the first-strand cDNA was synthesized by reverse transcription. Antibody VH and VL gene fragments were amplified and joined to a ScFv gene with the linker. The ScFv gene was ligated into the phagemid vector pCANTAB5E, which was transformed into competent E. coli TG1. The transformed cells were then infected with M13KO7 helper phage to yield the recombinant phage to construct the phage ScFv library. Pep-3-BSA protein was used to screen the phage antibody library and ELISA carried out to characterize the activity of the antibody. The VH and VL gene fragments of the antibody were about 350 bp and 320 bp in length as analyzed by agarose gel electrophoresis. The ScFv gene was 780 bp, consistent with the expected length. The recombinant phagemid with ScFv gene insert was rescued, and an immune phage ScFv library with the content of 5.0x10(6) was constructed. The recombinant ScFv phage had a titer of 3.0x10(4) cfu/ml, and the fourth phage harvest yielded 56 times as much as that of the first one. SDS-PAGE demonstrated a molecular mass of the soluble ScFv of about 28 kD. ELISA results indicated good specificity of the ScFv to bind EGFRvIII. An immune phage ScFv library is successfully constructed, and the ScFv antibody fragment is capable of specific binding to EGFRvIII.

Rapid and Programmable Protein Mutagenesis Using Plasmid Recombineering.

PubMed

Higgins, Sean A; Ouonkap, Sorel V Y; Savage, David F

2017-10-20

Comprehensive and programmable protein mutagenesis is critical for understanding structure-function relationships and improving protein function. There is thus a need for robust and unbiased molecular biological approaches for the construction of the requisite comprehensive protein libraries. Here we demonstrate that plasmid recombineering is a simple and robust in vivo method for the generation of protein mutants for both comprehensive library generation as well as programmable targeting of sequence space. Using the fluorescent protein iLOV as a model target, we build a complete mutagenesis library and find it to be specific and comprehensive, detecting 99.8% of our intended mutations. We then develop a thermostability screen and utilize our comprehensive mutation data to rapidly construct a targeted and multiplexed library that identifies significantly improved variants, thus demonstrating rapid protein engineering in a simple protocol.

Comparison of methods for library construction and short read annotation of shellfish viral metagenomes.

PubMed

Wei, Hong-Ying; Huang, Sheng; Wang, Jiang-Yong; Gao, Fang; Jiang, Jing-Zhe

2018-03-01

The emergence and widespread use of high-throughput sequencing technologies have promoted metagenomic studies on environmental or animal samples. Library construction for metagenome sequencing and annotation of the produced sequence reads are important steps in such studies and influence the quality of metagenomic data. In this study, we collected some marine mollusk samples, such as Crassostrea hongkongensis, Chlamys farreri, and Ruditapes philippinarum, from coastal areas in South China. These samples were divided into two batches to compare two library construction methods for shellfish viral metagenome. Our analysis showed that reverse-transcribing RNA into cDNA and then amplifying it simultaneously with DNA by whole genome amplification (WGA) yielded a larger amount of DNA compared to using only WGA or WTA (whole transcriptome amplification). Moreover, higher quality libraries were obtained by agarose gel extraction rather than with AMPure bead size selection. However, the latter can also provide good results if combined with the adjustment of the filter parameters. This, together with its simplicity, makes it a viable alternative. Finally, we compared three annotation tools (BLAST, DIAMOND, and Taxonomer) and two reference databases (NCBI's NR and Uniprot's Uniref). Considering the limitations of computing resources and data transfer speed, we propose the use of DIAMOND with Uniref for annotating metagenomic short reads as its running speed can guarantee a good annotation rate. This study may serve as a useful reference for selecting methods for Shellfish viral metagenome library construction and read annotation.

A novel suicide shuttle plasmid for Streptococcus suis serotype 2 and Streptococcus equi ssp. zooepidemicus gene mutation

PubMed Central

Liu, Rui; Zhang, Ping; Su, Yiqi; Lin, Huixing; Zhang, Hui; Yu, Lei; Ma, Zhe; Fan, Hongjie

2016-01-01

The mariner-based Himar1 system has been utilized for creating mutant libraries of many Gram-positive bacteria. Streptococcus suis serotype 2 (SS2) and Streptococcus equi ssp. zooepidemicus (SEZ) are primary pathogens of swine that threaten the swine industry in China. To provide a forward-genetics technology for finding virulent phenotype-related genes in these two pathogens, we constructed a novel temperature-sensitive suicide shuttle plasmid, pMar4s, which contains the Himar1 system transposon, TnYLB-1, and the Himar1 C9 transposase from pMarA and the repTAs temperature-sensitive fragment from pSET4s. The kanamycin (Kan) resistance gene was in the TnYLB-1 transposon. Temperature sensitivity and Kan resistance allowed the selection of mutant strains and construction of the mutant library. The SS2 and SEZ mutant libraries were successfully constructed using the pMar4s plasmid. Inverse-Polymerase Chain Reaction (Inverse-PCR) results revealed large variability in transposon insertion sites and that the library could be used for phenotype alteration screening. The thiamine biosynthesis gene apbE was screened for its influence on SS2 anti-phagocytosis; likewise, the sagF gene was identified to be a hemolytic activity-related gene in SEZ. pMar4s was suitable for mutant library construction, providing more information regarding SS2 and SEZ virulence factors and illustrating the pathogenesis of swine streptococcosis. PMID:27256117

Construction and Analysis of Siberian Tiger Bacterial Artificial Chromosome Library with Approximately 6.5-Fold Genome Equivalent Coverage

PubMed Central

Liu, Changqing; Bai, Chunyu; Guo, Yu; Liu, Dan; Lu, Taofeng; Li, Xiangchen; Ma, Jianzhang; Ma, Yuehui; Guan, Weijun

2014-01-01

Bacterial artificial chromosome (BAC) libraries are extremely valuable for the genome-wide genetic dissection of complex organisms. The Siberian tiger, one of the most well-known wild primitive carnivores in China, is an endangered animal. In order to promote research on its genome, a high-redundancy BAC library of the Siberian tiger was constructed and characterized. The library is divided into two sub-libraries prepared from blood cells and two sub-libraries prepared from fibroblasts. This BAC library contains 153,600 individually archived clones; for PCR-based screening of the library, BACs were placed into 40 superpools of 10 × 384-deep well microplates. The average insert size of BAC clones was estimated to be 116.5 kb, representing approximately 6.46 genome equivalents of the haploid genome and affording a 98.86% statistical probability of obtaining at least one clone containing a unique DNA sequence. Screening the library with 19 microsatellite markers and a SRY sequence revealed that each of these markers were present in the library; the average number of positive clones per marker was 6.74 (range 2 to 12), consistent with 6.46 coverage of the tiger genome. Additionally, we identified 72 microsatellite markers that could potentially be used as genetic markers. This BAC library will serve as a valuable resource for physical mapping, comparative genomic study and large-scale genome sequencing in the tiger. PMID:24608928

Developing expressed sequence tag libraries and the discovery of simple sequence repeat markers for two species of raspberry (Rubus L.).

PubMed

Bushakra, Jill M; Lewers, Kim S; Staton, Margaret E; Zhebentyayeva, Tetyana; Saski, Christopher A

2015-10-26

Due to a relatively high level of codominant inheritance and transferability within and among taxonomic groups, simple sequence repeat (SSR) markers are important elements in comparative mapping and delineation of genomic regions associated with traits of economic importance. Expressed sequence tags (ESTs) are a source of SSRs that can be used to develop markers to facilitate plant breeding and for more basic research across genera and higher plant orders. Leaf and meristem tissue from 'Heritage' red raspberry (Rubus idaeus) and 'Bristol' black raspberry (R. occidentalis) were utilized for RNA extraction. After conversion to cDNA and library construction, ESTs were sequenced, quality verified, assembled and scanned for SSRs.  Primers flanking the SSRs were designed and a subset tested for amplification, polymorphism and transferability across species. ESTs containing SSRs were functionally annotated using the GenBank non-redundant (nr) database and further classified using the gene ontology database. To accelerate development of EST-SSRs in the genus Rubus (Rosaceae), 1149 and 2358 cDNA sequences were generated from red raspberry and black raspberry, respectively. The cDNA sequences were screened using rigorous filtering criteria which resulted in the identification of 121 and 257 SSR loci for red and black raspberry, respectively. Primers were designed from the surrounding sequences resulting in 131 and 288 primer pairs, respectively, as some sequences contained more than one SSR locus. Sequence analysis revealed that the SSR-containing genes span a diversity of functions and share more sequence identity with strawberry genes than with other Rosaceous species. This resource of Rubus-specific, gene-derived markers will facilitate the construction of linkage maps composed of transferable markers for studying and manipulating important traits in this economically important genus.

Modular Construction of Large Non-Immune Human Antibody Phage-Display Libraries from Variable Heavy and Light Chain Gene Cassettes.

PubMed

Lee, Nam-Kyung; Bidlingmaier, Scott; Su, Yang; Liu, Bin

2018-01-01

Monoclonal antibodies and antibody-derived therapeutics have emerged as a rapidly growing class of biological drugs for the treatment of cancer, autoimmunity, infection, and neurological diseases. To support the development of human antibodies, various display techniques based on antibody gene repertoires have been constructed over the last two decades. In particular, scFv-antibody phage display has been extensively utilized to select lead antibodies against a variety of target antigens. To construct a scFv phage display that enables efficient antibody discovery, and optimization, it is desirable to develop a system that allows modular assembly of highly diverse variable heavy chain and light chain (Vκ and Vλ) repertoires. Here, we describe modular construction of large non-immune human antibody phage-display libraries built on variable gene cassettes from heavy chain and light chain repertoires (Vκ- and Vλ-light can be made into independent cassettes). We describe utility of such libraries in antibody discovery and optimization through chain shuffling.

Single-step colony assay for screening antibody libraries.

PubMed

Kato, Mieko; Hanyu, Yoshiro

2017-08-10

We describe a method, single-step colony assay, for simple and rapid screening of single-chain Fv fragment (scFv) libraries. Colonies of Escherichia coli expressing the scFv library are formed on a hydrophilic filter that is positioned in contact with a membrane coated with an antigen. scFv expression is triggered upon treatment of colonies with an induction reagent, following which scFvs are secreted from the cells and diffused to the antigen-coated membrane. scFvs that exhibit binding affinity for the antigen are captured by the membrane-immobilized antigen. Lastly, detection of scFv binding of the antigen on the membrane allows identification of the clones on the filter that express antigen-specific scFvs. We tested this methodology by using an anti-rabbit IgG scFv, scFv(A10B), and a rat immune scFv library. Experiments conducted using scFv(A10B) revealed that this method improves scFv expression during the colony assay. By using our method to screen an immune library of 3×10 3 scFv clones, we established several clones exhibiting affinity for the antigen. Moreover, we tested 7 other antigens, including peptides, and successfully identified positive clones. We believe that this simple procedure and controlled scFv expression of the single-step colony assay could make the antibody screening both rapid and reliable and lead to successful isolation of positive clones from antibody libraries. Copyright © 2017 Elsevier B.V. All rights reserved.

[RNA interference library research progress and its application in cancer research].

PubMed

Zhao, Ning; Cai, Li

2013-02-01

RNA interference is a homologous mRNA special degradation phenomenon which is caused by the double-stranded RNA. RNAi library is a pooled library that is artificially constructed using RNAi technology. As RNAi library has made a major breakthrough in the field of genetic research, it has been widely used in the field of medical research, especially in the field of cancer research. This review discussed the research progress of RNAi library and its applications in cancer research.

Preparation of cherry-picked combinatorial libraries by string synthesis.

PubMed

Furka, Arpád; Dibó, Gábor; Gombosuren, Naran

2005-03-01

String synthesis [1-3] is an efficient and cheap manual method for preparation of combinatorial libraries by using macroscopic solid support units. Sorting the units between two synthetic steps is an important operation of the procedure. The software developed to guide sorting can be used only when complete combinatorial libraries are prepared. Since very often only selected components of the full libraries are needed, new software was constructed that guides sorting in preparation of non-complete combinatorial libraries. Application of the software is described in details.

Normalized cDNA libraries

DOEpatents

Soares, Marcelo B.; Efstratiadis, Argiris

1997-01-01

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.

Normalized cDNA libraries

DOEpatents

Soares, M.B.; Efstratiadis, A.

1997-06-10

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3{prime} noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.

Public Access to Digital Material; A Call to Researchers: Digital Libraries Need Collaboration across Disciplines; Greenstone: Open-Source Digital Library Software; Retrieval Issues for the Colorado Digitization Project's Heritage Database; Report on the 5th European Conference on Digital Libraries, ECDL 2001; Report on the First Joint Conference on Digital Libraries.

ERIC Educational Resources Information Center

Kahle, Brewster; Prelinger, Rick; Jackson, Mary E.; Boyack, Kevin W.; Wylie, Brian N.; Davidson, George S.; Witten, Ian H.; Bainbridge, David; Boddie, Stefan J.; Garrison, William A.; Cunningham, Sally Jo; Borgman, Christine L.; Hessel, Heather

2001-01-01

These six articles discuss various issues relating to digital libraries. Highlights include public access to digital materials; intellectual property concerns; the need for collaboration across disciplines; Greenstone software for construction and presentation of digital information collections; the Colorado Digitization Project; and conferences…

Expression of a mutation causing hypertrophic cardiomyopathy disrupts sarcomere assembly in adult feline cardiac myocytes.

PubMed

Marian, A J; Yu, Q T; Mann, D L; Graham, F L; Roberts, R

1995-07-01

Mutations in the beta-myosin heavy chain (beta MyHC) induce hypertrophic cardiomyopathy (HCM), cardiac hypertrophy, and sarcomere disarray, with the latter being the characteristic hallmark. Thus, we sought to determine whether expression of mutant beta MyHC in adult feline cardiac myocytes, a species known to develop HCM with a phenotype identical to that in humans, induces sarcomere disarray. A full-length beta MyHC cDNA was cloned from a human heart cDNA library, and an HCM-causing mutation (Arg403Gln) was induced in the beta MyHC cDNA by site-directed mutagenesis using polymerase chain reaction (PCR). The normal and mutant beta MyHC cDNAs were cloned into p delta E1spIB shuttle vector, downstream from a cytomegalovirus (CMV) promoter. Replication-deficient recombinant adenoviral constructs (Ad5/CMV/beta MyHC-N and Ad5/CMV/beta MyHC-403) were generated through homologous recombination of p delta E1spIB/CMV/beta MyHC-N or Ad5/CMV/beta MyHC-403 and pBHG10 after cotransfection in 293 host cells. Infection of COS-1 cells with the beta MyHC construct resulted in the expression of a full-length myosin protein. Efficiency of infection of isolated adult cardiac myocytes was > 95%. Expression of the beta MyHC constructs into mRNA at 48 hours after infection of feline cardiac myocytes was confirmed by reverse transcription-PCR. The net total protein and beta-myosin synthesis were determined by using the amount of incorporation of [3H]phenylalanine into total protein and beta-myosin, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Genes expressed during the development and ripening of watermelon fruit.

PubMed

Levi, A; Davis, A; Hernandez, A; Wechter, P; Thimmapuram, J; Trebitsh, T; Tadmor, Y; Katzir, N; Portnoy, V; King, S

2006-11-01

A normalized cDNA library was constructed using watermelon flesh mRNA from three distinct developmental time-points and was subtracted by hybridization with leaf cDNA. Random cDNA clones of the watermelon flesh subtraction library were sequenced from the 5' end in order to identify potentially informative genes associated with fruit setting, development, and ripening. One-thousand and forty-six 5'-end sequences (expressed sequence tags; ESTs) were assembled into 832 non-redundant sequences, designated as "EST-unigenes". Of these 832 "EST-unigenes", 254 ( approximately 30%) have no significant homology to sequences published so far for other plant species. Additionally, 168 "EST-unigenes" ( approximately 20%) correspond to genes with unknown function, whereas 410 "EST-unigenes" ( approximately 50%) correspond to genes with known function in other plant species. These "EST-unigenes" are mainly associated with metabolism, membrane transport, cytoskeleton synthesis and structure, cell wall formation and cell division, signal transduction, nucleic acid binding and transcription factors, defense and stress response, and secondary metabolism. This study provides the scientific community with novel genetic information for watermelon as well as an expanded pool of genes associated with fruit development in watermelon. These genes will be useful targets in future genetic and functional genomic studies of watermelon and its development.

One step DNA assembly for combinatorial metabolic engineering.

PubMed

Coussement, Pieter; Maertens, Jo; Beauprez, Joeri; Van Bellegem, Wouter; De Mey, Marjan

2014-05-01

The rapid and efficient assembly of multi-step metabolic pathways for generating microbial strains with desirable phenotypes is a critical procedure for metabolic engineering, and remains a significant challenge in synthetic biology. Although several DNA assembly methods have been developed and applied for metabolic pathway engineering, many of them are limited by their suitability for combinatorial pathway assembly. The introduction of transcriptional (promoters), translational (ribosome binding site (RBS)) and enzyme (mutant genes) variability to modulate pathway expression levels is essential for generating balanced metabolic pathways and maximizing the productivity of a strain. We report a novel, highly reliable and rapid single strand assembly (SSA) method for pathway engineering. The method was successfully optimized and applied to create constructs containing promoter, RBS and/or mutant enzyme libraries. To demonstrate its efficiency and reliability, the method was applied to fine-tune multi-gene pathways. Two promoter libraries were simultaneously introduced in front of two target genes, enabling orthogonal expression as demonstrated by principal component analysis. This shows that SSA will increase our ability to tune multi-gene pathways at all control levels for the biotechnological production of complex metabolites, achievable through the combinatorial modulation of transcription, translation and enzyme activity. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

RNA-Seq Reveals Dynamic Changes of Gene Expression in Key Stages of Intestine Regeneration in the Sea Cucumber Apostichopus japonicas

PubMed Central

Sun, Lina; Yang, Hongsheng; Chen, Muyan; Ma, Deyou; Lin, Chenggang

2013-01-01

Background Sea cucumbers (Holothuroidea; Echinodermata) have the capacity to regenerate lost tissues and organs. Although the histological and cytological aspects of intestine regeneration have been extensively studied, little is known of the genetic mechanisms involved. There has, however, been a renewed effort to develop a database of Expressed Sequence Tags (ESTs) in Apostichopus japonicus, an economically-important species that occurs in China. This is important for studies on genetic breeding, molecular markers and special physiological phenomena. We have also constructed a library of ESTs obtained from the regenerative body wall and intestine of A. japonicus. The database has increased to ∼30000 ESTs. Results We used RNA-Seq to determine gene expression profiles associated with intestinal regeneration in A. japonicus at 3, 7, 14 and 21 days post evisceration (dpe). This was compared to profiles obtained from a normally-functioning intestine. Approximately 5 million (M) reads were sequenced in every library. Over 2400 up-regulated genes (>10%) and over 1000 down-regulated genes (∼5%) were observed at 3 and 7dpe (log2Ratio≥1, FDR≤0.001). Specific “Go terms” revealed that the DEGs (Differentially Expressed Genes) performed an important function at every regeneration stage. Besides some expected pathways (for example, Ribosome and Spliceosome pathway term), the “Notch signaling pathway,” the “ECM-receptor interaction” and the “Cytokine-cytokine receptor interaction” were significantly enriched. We also investigated the expression profiles of developmental genes, ECM-associated genes and Cytoskeletal genes. Twenty of the most important differentially expressed genes (DEGs) were verified by Real-time PCR, which resulted in a trend concordance of almost 100% between the two techniques. Conclusion Our studies demonstrated dynamic changes in global gene expression during intestine regeneration and presented a series of candidate genes and enriched pathways that contribute to intestine regeneration in sea cucumbers. This provides a foundation for future studies on the genetics/molecular mechanisms associated with intestine regeneration. PMID:23936330

Longview Public Library Final Performance Report for Library Services and Construction Act (LCSA) Title VI Library Literacy Program.

ERIC Educational Resources Information Center

Longview Public Library, WA.

Project Read at the Longview (Washington) Public Library conducted a program to maintain and expand the Family Literacy Center to provide a monitored tutoring site and family outreach program for a minimum of 75 adult learners and 40 tutors. Two projects were involved: (1) Project READ focused on adult learners with a one-on-one tutoring approach;…

Lewistown City Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

ERIC Educational Resources Information Center

Stead, Sharon

This final performance report for the Lewistown City Library L.E.A.R.N. (Let Every Adult Read Now!) literacy project begins with a section that provides quantitative data. The next section compares actual accomplishments to the following project goals for 1992-93: to serve a minimum of 25 adult literacy students within an 18-month period and to…

Subtractive transcriptome analysis of leaf and rhizome reveals differentially expressed transcripts in Panax sokpayensis.

PubMed

Gurung, Bhusan; Bhardwaj, Pardeep K; Talukdar, Narayan C

2016-11-01

In the present study, suppression subtractive hybridization (SSH) strategy was used to identify rare and differentially expressed transcripts in leaf and rhizome tissues of Panax sokpayensis. Out of 1102 randomly picked clones, 513 and 374 high quality expressed sequenced tags (ESTs) were generated from leaf and rhizome subtractive libraries, respectively. Out of them, 64.92 % ESTs from leaf and 69.26 % ESTs from rhizome SSH libraries were assembled into different functional categories, while others were of unknown function. In particular, ESTs encoding galactinol synthase 2, ribosomal RNA processing Brix domain protein, and cell division cycle protein 20.1, which are involved in plant growth and development, were most abundant in the leaf SSH library. Other ESTs encoding protein KIAA0664 homologue, ubiquitin-activating enzyme e11, and major latex protein, which are involved in plant immunity and defense response, were most abundant in the rhizome SSH library. Subtractive ESTs also showed similarity with genes involved in ginsenoside biosynthetic pathway, namely farnesyl pyrophosphate synthase, squalene synthase, and dammarenediol synthase. Expression profiles of selected ESTs validated the quality of libraries and confirmed their differential expression in the leaf, stem, and rhizome tissues. In silico comparative analyses revealed that around 13.75 % of unigenes from the leaf SSH library were not represented in the available leaf transcriptome of Panax ginseng. Similarly, around 18.12, 23.75, 25, and 6.25 % of unigenes from the rhizome SSH library were not represented in available root/rhizome transcriptomes of P. ginseng, Panax notoginseng, Panax quinquefolius, and Panax vietnamensis, respectively, indicating a major fraction of novel ESTs. Therefore, these subtractive transcriptomes provide valuable resources for gene discovery in P. sokpayensis and would complement the available transcriptomes from other Panax species.

Novel Lipolytic Enzymes Identified from Metagenomic Library of Deep-Sea Sediment

PubMed Central

Jeon, Jeong Ho; Kim, Jun Tae; Lee, Hyun Sook; Kim, Sang-Jin; Kang, Sung Gyun; Choi, Sang Ho; Lee, Jung-Hyun

2011-01-01

Metagenomic library was constructed from a deep-sea sediment sample and screened for lipolytic activity. Open-reading frames of six positive clones showed only 33–58% amino acid identities to the known proteins. One of them was assigned to a new group while others were grouped into Families I and V or EstD Family. By employing a combination of approaches such as removing the signal sequence, coexpression of chaperone genes, and low temperature induction, we obtained five soluble recombinant proteins in Escherichia coli. The purified enzymes had optimum temperatures of 30–35°C and the cold-activity property. Among them, one enzyme showed lipase activity by preferentially hydrolyzing p-nitrophenyl palmitate and p-nitrophenyl stearate and high salt resistance with up to 4 M NaCl. Our research demonstrates the feasibility of developing novel lipolytic enzymes from marine environments by the combination of functional metagenomic approach and protein expression technology. PMID:21845199

Whole-Cell Biocatalytic Synthesis of Cinnamyl Acetate with a Novel Esterase from the DNA Library of Acinetobacter hemolyticus.

PubMed

Dong, Hao; Secundo, Francesco; Xue, Changhu; Mao, Xiangzhao

2017-03-15

Cinnamyl acetate has a wide application in the flavor and fragrance industry because of its sweet, balsamic, and floral odor. Up to now, lipases have been mainly used in enzyme-mediated synthesis of cinnamyl acetate, whereas esterases are used in only a few cases. Moreover, the use of purified enzymes is often a disadvantage, which leads to increases of the production costs. In this paper, a genomic DNA library of Acinetobacter hemolyticus was constructed, and a novel esterase (EstK1) was identified. After expression in Escherichia coli, the whole-cell catalyst of EstK1 displayed high transesterification activity to produce cinnamyl acetate in nonaqueous systems. Furthermore, under optimal conditions (vinyl acetate as acyl donor, isooctane as solvent, molar ratio 1:4, temperature 40 °C), the conversion ratio of cinnamyl alcohol could be up to 94.1% at 1 h, and it reached an even higher level (97.1%) at 2 h.

Comprehensive discovery of noncoding RNAs in acute myeloid leukemia cell transcriptomes.

PubMed

Zhang, Jin; Griffith, Malachi; Miller, Christopher A; Griffith, Obi L; Spencer, David H; Walker, Jason R; Magrini, Vincent; McGrath, Sean D; Ly, Amy; Helton, Nichole M; Trissal, Maria; Link, Daniel C; Dang, Ha X; Larson, David E; Kulkarni, Shashikant; Cordes, Matthew G; Fronick, Catrina C; Fulton, Robert S; Klco, Jeffery M; Mardis, Elaine R; Ley, Timothy J; Wilson, Richard K; Maher, Christopher A

2017-11-01

To detect diverse and novel RNA species comprehensively, we compared deep small RNA and RNA sequencing (RNA-seq) methods applied to a primary acute myeloid leukemia (AML) sample. We were able to discover previously unannotated small RNAs using deep sequencing of a library method using broader insert size selection. We analyzed the long noncoding RNA (lncRNA) landscape in AML by comparing deep sequencing from multiple RNA-seq library construction methods for the sample that we studied and then integrating RNA-seq data from 179 AML cases. This identified lncRNAs that are completely novel, differentially expressed, and associated with specific AML subtypes. Our study revealed the complexity of the noncoding RNA transcriptome through a combined strategy of strand-specific small RNA and total RNA-seq. This dataset will serve as an invaluable resource for future RNA-based analyses. Copyright © 2017 ISEH – Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

Construction and functional analysis of Trichoderma harzianum mutants that modulate maize resistance to the pathogen Curvularia lunata.

PubMed

Fan, Lili; Fu, Kehe; Yu, Chuanjin; Ma, Jia; Li, Yaqian; Chen, Jie

2014-01-01

Agrobacterium tumefaciens-mediated transformation (ATMT) was used to generate an insertional mutant library of the mycelial fungus Trichoderma harzianum. From a total of 450 mutants, six mutants that showed significant influence on maize resistance to C. lunata were analyzed in detail. Maize coated with these mutants was more susceptible to C. lunata compared with those coated with a wild-type (WT) strain. Similar to other fungal ATMT libraries, all six mutants were single copy integrations, which occurred preferentially in noncoding regions (except two mutants) and were frequently accompanied by the loss of border sequences. Two mutants (T66 and T312) that were linked to resistance were characterized further. Maize seeds coated with T66 and T312 were more susceptible to C. lunata than those treated with WT. Moreover, the mutants affected the resistance of maize to C. lunata by enhancing jasmonate-responsive gene expression. T66 and T312 induced maize resistance to C. lunata infection through a jasmonic acid-dependent pathway.

45 CFR 1706.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE...

45 CFR 1706.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE...

45 CFR 1706.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE...

45 CFR 1706.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE...

45 CFR 1706.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE...

Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Ze

2012-06-01

Ze Peng from DOE JGI presents "Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library" at the 7th Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held in June, 2012 in Santa Fe, NM.

Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)

ScienceCinema

Peng, Ze

2018-01-24

Ze Peng from DOE JGI presents "Fosmid Cre-LoxP Inverse PCR Paired-End (Fosmid CLIP-PE), a Novel Method for Constructing Fosmid Pair-End Library" at the 7th Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held in June, 2012 in Santa Fe, NM.

Relationship of Technology and Characteristics of Library Functional Units.

ERIC Educational Resources Information Center

Lynch, Beverly P.; Verdin, Jo Ann

The project summarized in this report collected data from 3 of the 25 largest Association of Research Library (ARL) member libraries in order to: (1) examine the durability of the measure of technology set forth in "An Empirical Assessment of Perrow's Technology Construct" (Administrative Science Quarterly, 1974, pp. 338-356); (2) study…

Supplementary Materials for State Penitentiary Library Project. Final Performance Report.

ERIC Educational Resources Information Center

Hull, Jane A.

This report describes how a Library Services and Construction Act (LSCA) Title VI Library Literacy Program grant was used to improve the literacy and coping skills of illiterate and functionally illiterate inmates incarcerated at the Mississippi State Penitentiary. A second objective of this literacy program was to produce an annotated…

The Philip Morris Information Network: A Library Database on an In-House Timesharing System.

ERIC Educational Resources Information Center

DeBardeleben, Marian Z.; And Others

1983-01-01

Outlines a database constructed at Philip Morris Research Center Library which encompasses holdings and circulation and acquisitions records for all items in the library. Host computer (DECSYSTEM-2060), software (BASIC), database design, search methodology, cataloging, and accessibility are noted; sample search, circ-in profile, end user profiles,…

Constructing and Reading Visual Information: Visual Literacy for Library and Information Science Education

ERIC Educational Resources Information Center

Ma, Yan

2015-01-01

This article examines visual literacy education and research for library and information science profession to educate the information professionals who will be able to execute and implement the ACRL (Association of College and Research Libraries) Visual Literacy Competency Standards successfully. It is a continuing call for inclusion of visual…

Annual Report on LSCA Priorities. FY 1982.

ERIC Educational Resources Information Center

Office of Educational Research and Improvement (ED), Washington, DC. Center for Libraries and Education Improvement.

This collection of six reports was compiled by the State and Public Library Services Branch of the United States Department of Education to disseminate pertinent information submitted by the State Library Administrative Agencies on the Library Services and Construction Act (LSCA) priority areas. Based on data from the fiscal year 1982 LSCA Annual…

Library Services in Institutions for Mentally and Developmentally Disabled Adults.

ERIC Educational Resources Information Center

Ensor, Pat

To improve the quality of life of institutionalized individuals, libraries can serve as a constructive escape mechanism for dealing with stress, a representation of external reality, and a therapeutic agent, in addition to offering bibliotherapy. Ideally, the library should be an integral part of the institution and provide a user-appropriate…

Educational Resources in the ASCC Library

ERIC Educational Resources Information Center

Lin, Steven

2006-01-01

After two years of construction, American Samoa Community College opened its new library on September 2, 2003. The library is located on the east side of campus and is equipped with ten computer workstations, four online public access catalogs, three copying machines, and an elevator that is in compliance with the Americans with Disabilities Act.…

Unwrapping the Bundle: An Examination of Research Libraries and the "Big Deal"

ERIC Educational Resources Information Center

Strieb, Karla L.; Blixrud, Julia C.

2014-01-01

This study presents and analyzes the findings of a 2012 survey of member libraries belonging to the Association of Research Libraries (ARL) about publishers' large journal bundles and compares the results to earlier surveys. The data illuminate five research questions: market penetration, journal bundle construction, collection format shifts,…

Disaster Response and Planning for Libraries, Third Edition

ERIC Educational Resources Information Center

Kahn, Miriam B.

2012-01-01

Fire, water, mold, construction problems, power-outages--mishaps like these can not only bring library services to a grinding halt, but can also destroy collections and even endanger employees. Preparing for the unexpected is the foundation of a library's best response. Expert Kahn comes to the rescue with this timely update of the best…

In Quest of the Perfect Library

ERIC Educational Resources Information Center

Holleran, Andrew

2007-01-01

There is a sad truth about college libraries: No matter how attractively designed and cleverly constructed, they cannot disguise a central fact--that the undergraduates in them are seldom there to read books they want to read. The author explains that when he walks through the library at Georgetown University or American University, his heart goes…