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1

Construction and screening of BAC libraries made from Brachypodium genomic DNA  

Microsoft Academic Search

Bacterial artificial chromosome (BAC) libraries are the large DNA insert libraries of choice and valuable tools for the map-based cloning of target quantitative trait loci, physical mapping, molecular cytogenetics and comparative genomics. The protocol reported here is a simplified method used to produce and screen BAC libraries from Brachypodium species and other related grasses. Intact nuclei, containing high molecular weight

Iain S Donnison; Kerrie Farrar

2007-01-01

2

Tuatara (Sphenodon) Genomics: BAC Library Construction, Sequence Survey, and Application to the DMRT Gene Family  

Microsoft Academic Search

The tuatara (Sphenodon punctatus) is of ''extraordinary biological interest'' as the most distinctive surviving reptilian lineage (Rhyncocephalia) in the world. To provide a genomic resource for an understanding of genome evolution in reptiles, and as part of a larger project to produce genomic resources for various reptiles (http:\\/\\/evogen.jgi.doe.gov\\/second_ levels\\/BACs\\/Our_libraries.html), a large-insert bacterial artificial chromosome (BAC) library from a male tuatara

ZHENSHAN WANG; T. Miyake; S. V. Edwards; C. T. Amemiya

2006-01-01

3

Mining non-model genomic libraries for microsatellites: BAC versus EST libraries and the generation of allelic richness  

PubMed Central

Background Simple sequence repeats (SSRs) are tandemly repeated sequence motifs common in genomic nucleotide sequence that often harbor significant variation in repeat number. Frequently used as molecular markers, SSRs are increasingly identified via in silico approaches. Two common classes of genomic resources that can be mined are bacterial artificial chromosome (BAC) libraries and expressed sequence tag (EST) libraries. Results 288 SSR loci were screened in the rapidly radiating Hawaiian swordtail cricket genus Laupala. SSRs were more densely distributed and contained longer repeat structures in BAC library-derived sequence than in EST library-derived sequence, although neither repeat density nor length was exceptionally elevated despite the relatively large genome size of Laupala. A non-random distribution favoring AT-rich SSRs was observed. Allelic diversity of SSRs was positively correlated with repeat length and was generally higher in AT-rich repeat motifs. Conclusion The first large-scale survey of Orthopteran SSR allelic diversity is presented. Selection contributes more strongly to the size and density distributions of SSR loci derived from EST library sequence than from BAC library sequence, although all SSRs likely are subject to similar physical and structural constraints, such as slippage of DNA replication machinery, that may generate increased allelic diversity in AT-rich sequence motifs. Although in silico approaches work well for SSR locus identification in both EST and BAC libraries, BAC library sequence and AT-rich repeat motifs are generally superior SSR development resources for most applications.

2010-01-01

4

Toward an Integrated BAC Library Resource for Genome Sequencing and Analysis  

SciTech Connect

We developed a great deal of expertise in building large BAC libraries from a variety of DNA sources including humans, mice, corn, microorganisms, worms, and Arabidopsis. We greatly improved the technology for screening these libraries rapidly and for selecting appropriate BACs and mapping BACs to develop large overlapping contigs. We became involved in supplying BACs and BAC contigs to a variety of sequencing and mapping projects and we began to collaborate with Drs. Adams and Venter at TIGR and with Dr. Leroy Hood and his group at University of Washington to provide BACs for end sequencing and for mapping and sequencing of large fragments of chromosome 16. Together with Dr. Ian Dunham and his co-workers at the Sanger Center we completed the mapping and they completed the sequencing of the first human chromosome, chromosome 22. This was published in Nature in 1999 and our BAC contigs made a major contribution to this sequencing effort. Drs. Shizuya and Ding invented an automated highly accurate BAC mapping technique. We also developed long-term collaborations with Dr. Uli Weier at UCSF in the design of BAC probes for characterization of human tumors and specific chromosome deletions and breakpoints. Finally the contribution of our work to the human genome project has been recognized in the publication both by the international consortium and the NIH of a draft sequence of the human genome in Nature last year. Dr. Shizuya was acknowledged in the authorship of that landmark paper. Dr. Simon was also an author on the Venter/Adams Celera project sequencing the human genome that was published in Science last year.

Simon, M. I.; Kim, U.-J.

2002-02-26

5

Tuatara (Sphenodon) genomics: BAC library construction, sequence survey, and application to the DMRT gene family.  

PubMed

The tuatara (Sphenodon punctatus) is of "extraordinary biological interest" as the most distinctive surviving reptilian lineage (Rhyncocephalia) in the world. To provide a genomic resource for an understanding of genome evolution in reptiles, and as part of a larger project to produce genomic resources for various reptiles (evogen.jgi.doe.gov/second_levels/BACs/our_libraries.html), a large-insert bacterial artificial chromosome (BAC) library from a male tuatara was constructed. The library consists of 215 424 individual clones whose average insert size was empirically determined to be 145 kb, yielding a genomic coverage of approximately 6.3x. A BAC-end sequencing analysis of 121 420 bp of sequence revealed a genomic GC content of 46.8%, among the highest observed thus far for vertebrates, and identified several short interspersed repetitive elements (mammalian interspersed repeat-type repeats) and long interspersed repetitive elements, including chicken repeat 1 element. Finally, as a quality control measure the arrayed library was screened with probes corresponding to 2 conserved noncoding regions of the candidate sex-determining gene DMRT1 and the DM domain of the related DMRT2 gene. A deep coverage contig spanning nearly 300 kb was generated, supporting the deep coverage and utility of the library for exploring tuatara genomics. PMID:17135461

Wang, Zhenshan; Miyake, Tsutomu; Edwards, Scott V; Amemiya, Chris T

2006-11-29

6

Enhancing genome investigations in the mosquito Culex quinquefasciatus via BAC library construction and characterization  

PubMed Central

Background Culex quinquefasciatus (Say) is a major species in the Culex pipiens complex and an important vector for several human pathogens including West Nile virus and parasitic filarial nematodes causing lymphatic filariasis. It is common throughout tropical and subtropical regions and is among the most geographically widespread mosquito species. Although the complete genome sequence is now available, additional genomic tools are needed to improve the sequence assembly. Findings We constructed a bacterial artificial chromosome (BAC) library using the pIndigoBAC536 vector and HindIII partially digested DNA isolated from Cx. quinquefasciatus pupae, Johannesburg strain (NDJ). Insert size was estimated by NotI digestion and pulsed-field gel electrophoresis of 82 randomly selected clones. To estimate genome coverage, each 384-well plate was pooled for screening with 29 simple sequence repeat (SSR) and five gene markers. The NDJ library consists of 55,296 clones arrayed in 144 384-well microplates. Fragment insert size ranged from 50 to 190 kb in length (mean = 106 kb). Based on a mean insert size of 106 kb and a genome size of 579 Mbp, the BAC library provides ~10.1-fold coverage of the Cx. quinquefasciatus genome. PCR screening of BAC DNA plate pools for SSR loci from the genetic linkage map and for four genes associated with reproductive diapause in Culex pipiens resulted in a mean of 9.0 positive plate pools per locus. Conclusion The NDJ library represents an excellent resource for genome assembly enhancement and characterization in Culex pipiens complex mosquitoes.

2011-01-01

7

Construction and characterisation of a BAC library for genome analysis of the allotetraploid coffee species ( Coffea arabica L.)  

Microsoft Academic Search

In order to promote genome research on coffee trees, one of the most important tropical crops, a bacterial artificial chromosome (BAC) library of the coffee allotetraploid species, Coffea arabica, was constructed. The variety IAPAR 59, which is widely distributed in Latin America and exhibits a fair level of resistance to several pathogens, was chosen. High-efficiency BAC cloning of the high

S. Noir; S. Patheyron; M.-C. Combes; P. Lashermes; B. Chalhoub

2004-01-01

8

Comparative genomics of Lupinus angustifolius gene-rich regions: BAC library exploration, genetic mapping and cytogenetics  

PubMed Central

Background The narrow-leafed lupin, Lupinus angustifolius L., is a grain legume species with a relatively compact genome. The species has 2n?=?40 chromosomes and its genome size is 960 Mbp/1C. During the last decade, L. angustifolius genomic studies have achieved several milestones, such as molecular-marker development, linkage maps, and bacterial artificial chromosome (BAC) libraries. Here, these resources were integratively used to identify and sequence two gene-rich regions (GRRs) of the genome. Results The genome was screened with a probe representing the sequence of a microsatellite fragment length polymorphism (MFLP) marker linked to Phomopsis stem blight resistance. BAC clones selected by hybridization were subjected to restriction fingerprinting and contig assembly, and 232 BAC-ends were sequenced and annotated. BAC fluorescence in situ hybridization (BAC-FISH) identified eight single-locus clones. Based on physical mapping, cytogenetic localization, and BAC-end annotation, five clones were chosen for sequencing. Within the sequences of clones that hybridized in FISH to a single-locus, two large GRRs were identified. The GRRs showed strong and conserved synteny to Glycine max duplicated genome regions, illustrated by both identical gene order and parallel orientation. In contrast, in the clones with dispersed FISH signals, more than one-third of sequences were transposable elements. Sequenced, single-locus clones were used to develop 12 genetic markers, increasing the number of L. angustifolius chromosomes linked to appropriate linkage groups by five pairs. Conclusions In general, probes originating from MFLP sequences can assist genome screening and gene discovery. However, such probes are not useful for positional cloning, because they tend to hybridize to numerous loci. GRRs identified in L. angustifolius contained a low number of interspersed repeats and had a high level of synteny to the genome of the model legume G. max. Our results showed that not only was the gene nucleotide sequence conserved between soybean and lupin GRRs, but the order and orientation of particular genes in syntenic blocks was homologous, as well. These findings will be valuable to the forthcoming sequencing of the lupin genome.

2013-01-01

9

Genome Enablement of the Notothenioidei: Genome Size Estimates from 11 Species and BAC Libraries from 2 Representative Taxa  

PubMed Central

The perciform suborder Notothenoidei provides a compelling opportunity to study the adaptive radiation of a marine species flock in the cold Southern Ocean surrounding Antarctica. To enable genome-level studies of these psychrophilic fishes, we estimated the sizes of the genomes of 11 Antarctic species and generated high-quality BAC libraries for 2, the notothen Notothenia coriiceps and the icefish Chaenocephalus aceratus. Our results indicate that evolution of phylogenetically derived notothenioid families, [e.g., the icefishes (Channichthyidae)], was accompanied by genome expansion. Species (n = 6) of the basal family Nototheniidae had C values that ranged between 0.98 and 1.20 pg, whereas those of the icefishes, the notothenioid crown group, were 1.66–1.83 pg (n = 4 species). The BAC libraries VMRC-19 (N. coriiceps) and VMRC-21 (C. aceratus) comprised 12X and 10X coverage of the respective genomes and had average insert sizes of 138 and 168 kb. Greater than 60% of paired BAC ends sampled from each library (~0.1% of each genome) contained repetitive sequences, and the repetitive element landscapes of the 2 genomes (13.4% of the N. coriiceps genome and 14.5% for C. aceratus) were similar. The representation and depth of coverage of the libraries were verified by identification of multiple Hox gene contigs: six discrete Hox clusters were found in N. coriiceps and at least five Hox clusters were found in C. aceratus. Given the unusual anatomical and physiological adaptations of the notothenioids, the availability of these BAC libraries sets the stage for expanded analysis of the psychrophilic mode of life.

DETRICH, H. WILLIAM; STUART, ANDREW; SCHOENBORN, MICHAEL; PARKER, SANDRA K.; METHE, BARBARA A.; AMEMIYA, CHRIS T.

2013-01-01

10

Genome enablement of the notothenioidei: genome size estimates from 11 species and BAC libraries from 2 representative taxa.  

PubMed

The perciform suborder Notothenoidei provides a compelling opportunity to study the adaptive radiation of a marine species flock in the cold Southern Ocean surrounding Antarctica. To enable genome-level studies of these psychrophilic fishes, we estimated the sizes of the genomes of 11 Antarctic species and generated high-quality BAC libraries for 2, the notothen Notothenia coriiceps and the icefish Chaenocephalus aceratus. Our results indicate that evolution of phylogenetically derived notothenioid families, [e.g., the icefishes (Channichthyidae)], was accompanied by genome expansion. Species (n=6) of the basal family Nototheniidae had C values that ranged between 0.98 and 1.20 pg, whereas those of the icefishes, the notothenioid crown group, were 1.66-1.83 pg (n=4 species). The BAC libraries VMRC-19 (N. coriiceps) and VMRC-21 (C. aceratus) comprised 12X and 10X coverage of the respective genomes and had average insert sizes of 138 and 168 kb. Greater than 60% of paired BAC ends sampled from each library ( approximately 0.1% of each genome) contained repetitive sequences, and the repetitive element landscapes of the 2 genomes (13.4% of the N. coriiceps genome and 14.5% for C. aceratus) were similar. The representation and depth of coverage of the libraries were verified by identification of multiple Hox gene contigs: six discrete Hox clusters were found in N. coriiceps and at least five Hox clusters were found in C. aceratus. Given the unusual anatomical and physiological adaptations of the notothenioids, the availability of these BAC libraries sets the stage for expanded analysis of the psychrophilic mode of life. PMID:20235119

Detrich, H William; Stuart, Andrew; Schoenborn, Michael; Parker, Sandra K; Methé, Barbara A; Amemiya, Chris T

2010-07-15

11

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

PubMed Central

Background 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. Results 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. Conclusions 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.

2011-01-01

12

The 19 genomes of Drosophila: a BAC library resource for genus-wide and genome-scale comparative evolutionary research.  

PubMed

The genus Drosophila has been the subject of intense comparative phylogenomics characterization to provide insights into genome evolution under diverse biological and ecological contexts and to functionally annotate the Drosophila melanogaster genome, a model system for animal and insect genetics. Recent sequencing of 11 additional Drosophila species from various divergence points of the genus is a first step in this direction. However, to fully reap the benefits of this resource, the Drosophila community is faced with two critical needs: i.e., the expansion of genomic resources from a much broader range of phylogenetic diversity and the development of additional resources to aid in finishing the existing draft genomes. To address these needs, we report the first synthesis of a comprehensive set of bacterial artificial chromosome (BAC) resources for 19 Drosophila species from all three subgenera. Ten libraries were derived from the exact source used to generate 10 of the 12 draft genomes, while the rest were generated from a strategically selected set of species on the basis of salient ecological and life history features and their phylogenetic positions. The majority of the new species have at least one sequenced reference genome for immediate comparative benefit. This 19-BAC library set was rigorously characterized and shown to have large insert sizes (125-168 kb), low nonrecombinant clone content (0.3-5.3%), and deep coverage (9.1-42.9×). Further, we demonstrated the utility of this BAC resource for generating physical maps of targeted loci, refining draft sequence assemblies and identifying potential genomic rearrangements across the phylogeny. PMID:21321134

Song, Xiang; Goicoechea, Jose Luis; Ammiraju, Jetty S S; Luo, Meizhong; He, Ruifeng; Lin, Jinke; Lee, So-Jeong; Sisneros, Nicholas; Watts, Tom; Kudrna, David A; Golser, Wolfgang; Ashley, Elizabeth; Collura, Kristi; Braidotti, Michele; Yu, Yeisoo; Matzkin, Luciano M; McAllister, Bryant F; Markow, Therese Ann; Wing, Rod A

2011-02-14

13

The 19 Genomes of Drosophila: A BAC Library Resource for Genus-Wide and Genome-Scale Comparative Evolutionary Research  

PubMed Central

The genus Drosophila has been the subject of intense comparative phylogenomics characterization to provide insights into genome evolution under diverse biological and ecological contexts and to functionally annotate the Drosophila melanogaster genome, a model system for animal and insect genetics. Recent sequencing of 11 additional Drosophila species from various divergence points of the genus is a first step in this direction. However, to fully reap the benefits of this resource, the Drosophila community is faced with two critical needs: i.e., the expansion of genomic resources from a much broader range of phylogenetic diversity and the development of additional resources to aid in finishing the existing draft genomes. To address these needs, we report the first synthesis of a comprehensive set of bacterial artificial chromosome (BAC) resources for 19 Drosophila species from all three subgenera. Ten libraries were derived from the exact source used to generate 10 of the 12 draft genomes, while the rest were generated from a strategically selected set of species on the basis of salient ecological and life history features and their phylogenetic positions. The majority of the new species have at least one sequenced reference genome for immediate comparative benefit. This 19-BAC library set was rigorously characterized and shown to have large insert sizes (125–168 kb), low nonrecombinant clone content (0.3–5.3%), and deep coverage (9.1–42.9×). Further, we demonstrated the utility of this BAC resource for generating physical maps of targeted loci, refining draft sequence assemblies and identifying potential genomic rearrangements across the phylogeny.

Song, Xiang; Goicoechea, Jose Luis; Ammiraju, Jetty S. S.; Luo, Meizhong; He, Ruifeng; Lin, Jinke; Lee, So-Jeong; Sisneros, Nicholas; Watts, Tom; Kudrna, David A.; Golser, Wolfgang; Ashley, Elizabeth; Collura, Kristi; Braidotti, Michele; Yu, Yeisoo; Matzkin, Luciano M.; McAllister, Bryant F.; Markow, Therese Ann; Wing, Rod A.

2011-01-01

14

Construction of BAC libraries from two apomictic grasses to study the microcolinearity of their apospory-specific genomic regions  

Microsoft Academic Search

We have constructed bacterial artificial chromosome (BAC) libraries from two grass species that reproduce by apospory, a form of gametophytic apomixis. The library of an apomictic polyhaploid genotype (line MS228-20, with a 2C genome size of approximately 4,500 Mbp) derived from a cross between the obligate apomict, Pennisetum squamulatum, and pearl millet (P. glaucum) comprises 118,272 clones with an average

D. Roche; J. A. Conner; M. A. Budiman; D. Frisch; R. Wing; W. W. Hanna; P. Ozias-Akins

2002-01-01

15

Construction and characterization of the IGF Arabidopsis BAC library  

Microsoft Academic Search

A bacterial artificial chromosome (BAC) library has been established for Arabidopsis thaliana (ecotype Col-0) covering about seven haploid nuclear genome equivalents. This library, called the Institut für Genbiologische\\u000a Forschung (IGF) BAC library, consists of 10?752 recombinant clones carrying inserts (generated by partial EcoRI digestion) of an average size of about 100?kb in a modified BAC vector, pBeloBAC-Kan. Hybridization with organellar

T. Mozo; S. Fischer; H. Shizuya; T. Altmann

1998-01-01

16

Development of BAC libraries and integrated physical mapping of human chromosome 22 using BACs. Annual report, July 1994--June 1995  

SciTech Connect

BACs and fosmids are stable, nonchimeric, and highly representative cloning systems. BACs maintain large-fragment genomic inserts (100 to 300 kb) that are easily prepared for most types of experiments, including DNA sequencing. The authors have improved the methods for generating BACs and developed extensive BAC libraries. They have constructed human BAC libraries with more than 175,000 clones from male fibroblast and sperm, and a mouse BAC library with more than 200,000 clones. The authors are currently expanding human library with the aim of achieving total 50X coverage human genomic library using sperm samples from anonymous donors.

Kim, U.J.; Shizuya, Hiroaki; Simon, M.I.

1995-12-31

17

Adventures in the enormous: a 1.8 million clone BAC library for the 21.7 Gb genome of loblolly pine.  

PubMed

Loblolly pine (LP; Pinus taeda L.) is the most economically important tree in the U.S. and a cornerstone species in southeastern forests. However, genomics research on LP and other conifers has lagged behind studies on flowering plants due, in part, to the large size of conifer genomes. As a means to accelerate conifer genome research, we constructed a BAC library for the LP genotype 7-56. The LP BAC library consists of 1,824,768 individually-archived clones making it the largest single BAC library constructed to date, has a mean insert size of 96 kb, and affords 7.6X coverage of the 21.7 Gb LP genome. To demonstrate the efficacy of the library in gene isolation, we screened macroarrays with overgos designed from a pine EST anchored on LP chromosome 10. A positive BAC was sequenced and found to contain the expected full-length target gene, several gene-like regions, and both known and novel repeats. Macroarray analysis using the retrotransposon IFG-7 (the most abundant repeat in the sequenced BAC) as a probe indicates that IFG-7 is found in roughly 210,557 copies and constitutes about 5.8% or 1.26 Gb of LP nuclear DNA; this DNA quantity is eight times the Arabidopsis genome. In addition to its use in genome characterization and gene isolation as demonstrated herein, the BAC library should hasten whole genome sequencing of LP via next-generation sequencing strategies/technologies and facilitate improvement of trees through molecular breeding and genetic engineering. The library and associated products are distributed by the Clemson University Genomics Institute (www.genome.clemson.edu). PMID:21283709

Magbanua, Zenaida V; Ozkan, Seval; Bartlett, Benjamin D; Chouvarine, Philippe; Saski, Christopher A; Liston, Aaron; Cronn, Richard C; Nelson, C Dana; Peterson, Daniel G

2011-01-21

18

Adventures in the Enormous: A 1.8 Million Clone BAC Library for the 21.7 Gb Genome of Loblolly Pine  

PubMed Central

Loblolly pine (LP; Pinus taeda L.) is the most economically important tree in the U.S. and a cornerstone species in southeastern forests. However, genomics research on LP and other conifers has lagged behind studies on flowering plants due, in part, to the large size of conifer genomes. As a means to accelerate conifer genome research, we constructed a BAC library for the LP genotype 7-56. The LP BAC library consists of 1,824,768 individually-archived clones making it the largest single BAC library constructed to date, has a mean insert size of 96 kb, and affords 7.6X coverage of the 21.7 Gb LP genome. To demonstrate the efficacy of the library in gene isolation, we screened macroarrays with overgos designed from a pine EST anchored on LP chromosome 10. A positive BAC was sequenced and found to contain the expected full-length target gene, several gene-like regions, and both known and novel repeats. Macroarray analysis using the retrotransposon IFG-7 (the most abundant repeat in the sequenced BAC) as a probe indicates that IFG-7 is found in roughly 210,557 copies and constitutes about 5.8% or 1.26 Gb of LP nuclear DNA; this DNA quantity is eight times the Arabidopsis genome. In addition to its use in genome characterization and gene isolation as demonstrated herein, the BAC library should hasten whole genome sequencing of LP via next-generation sequencing strategies/technologies and facilitate improvement of trees through molecular breeding and genetic engineering. The library and associated products are distributed by the Clemson University Genomics Institute (www.genome.clemson.edu).

Magbanua, Zenaida V.; Ozkan, Seval; Bartlett, Benjamin D.; Chouvarine, Philippe; Saski, Christopher A.; Liston, Aaron; Cronn, Richard C.; Nelson, C. Dana; Peterson, Daniel G.

2011-01-01

19

Construction of a California condor BAC library and first-generation chicken-condor comparative physical map as an endangered species conservation genomics resource.  

PubMed

To support genomic analysis of the endangered California condor (Gymnogyps californianus), a BAC library (CHORI-262) was generated using DNA from the blood of a female. The library consists of 89,665 recombinant BAC clones providing approximately 14-fold coverage of the presumed approximately 1.48-Gb genome. Taking advantage of recent progress in chicken genomics, we developed a first-generation comparative chicken-condor physical map using an overgo hybridization approach. The overgos were derived from chicken (164 probes) and New World vulture (8 probes) sequences. Screening a 2.8x subset of the total library resulted in 236 BAC-gene assignments with 2.5 positive BAC clones per successful probe. A preliminary comparative chicken-condor BAC-based map included 93 genes. Comparison of selected condor BAC sequences with orthologous chicken sequences suggested a high degree of conserved synteny between the two avian genomes. This work will aid in identification and characterization of candidate loci for the chondrodystrophy mutation to advance genetic management of this disease. PMID:16884891

Romanov, Michael N; Koriabine, Maxim; Nefedov, Mikhail; de Jong, Pieter J; Ryder, Oliver A

2006-08-01

20

Construction and characterization of two BAC libraries representing a deep-coverage of the genome of chicory (Cichorium intybus L., Asteraceae)  

Microsoft Academic Search

BACKGROUND: The Asteraceae represents an important plant family with respect to the numbers of species present in the wild and used by man. Nonetheless, genomic resources for Asteraceae species are relatively underdeveloped, hampering within species genetic studies as well as comparative genomics studies at the family level. So far, six BAC libraries have been described for the main crops of

Lucy Gonthier; Arnaud Bellec; Christelle Blassiau; Elisa Prat; Nicolas Helmstetter; Caroline Rambaud; Brigitte Huss; Theo Hendriks; Hélčne Bergčs; Marie-Christine Quillet

2010-01-01

21

Construction of genome-wide physical BAC contigs using mapped cDNA as probes: Toward an integrated BAC library resource for genome sequencing and analysis. Annual report, July 1995--January 1997  

SciTech Connect

The goal of human genome project is to characterize and sequence entire genomes of human and several model organisms, thus providing complete sets of information on the entire structure of transcribed, regulatory and other functional regions for these organisms. In the past years, a number of useful genetic and physical markers on human and mouse genomes have been made available along with the advent of BAC library resources for these organisms. The advances in technology and resource development made it feasible to efficiently construct genome-wide physical BAC contigs for human and other genomes. Currently, over 30,000 mapped STSs and 27,000 mapped Unigenes are available for human genome mapping. ESTs and cDNAs are excellent resources for building contig maps for two reasons. Firstly, they exist in two alternative forms--as both sequence information for PCR primer pairs, and cDoreen genomic libraries efficiently for large number of DNA probes by combining over 100 cDNA probes in each hybridization. Second, the linkage and order of genes are rather conserved among human, mouse and other model organisms. Therefore, gene markers have advantages over random anonymous STSs in building maps for comparative genomic studies.

Mitchell, S.C.; Bocskai, D.; Cao, Y. [and others

1997-12-31

22

Construction of a BAC library and mapping BAC clones to the linkage map of Barramundi, Lates calcarifer  

PubMed Central

Background Barramundi (Lates calcarifer) is an important farmed marine food fish species. Its first generation linkage map has been applied to map QTL for growth traits. To identify genes located in QTL responsible for specific traits, genomic large insert libraries are of crucial importance. We reported herein a bacterial artificial chromosome (BAC) library and the mapping of BAC clones to the linkage map. Results This BAC library consisted of 49,152 clones with an average insert size of 98 kb, representing 6.9-fold haploid genome coverage. Screening the library with 24 microsatellites and 15 ESTs/genes demonstrated that the library had good genome coverage. In addition, 62 novel microsatellites each isolated from 62 BAC clones were mapped onto the first generation linkage map. A total of 86 BAC clones were anchored on the linkage map with at least one BAC clone on each linkage group. Conclusion We have constructed the first BAC library for L. calcarifer and mapped 86 BAC clones to the first generation linkage map. This BAC library and the improved linkage map with 302 DNA markers not only supply an indispensable tool to the integration of physical and linkage maps, the fine mapping of QTL and map based cloning genes located in QTL of commercial importance, but also contribute to comparative genomic studies and eventually whole genome sequencing.

Wang, Chun Ming; Lo, Loong Chueng; Feng, Felicia; Gong, Ping; Li, Jian; Zhu, Ze Yuan; Lin, Grace; Yue, Gen Hua

2008-01-01

23

Construction of a BAC library and mapping BAC clones to the linkage map of Barramundi, Lates calcarifer  

Microsoft Academic Search

BACKGROUND: Barramundi (Lates calcarifer) is an important farmed marine food fish species. Its first generation linkage map has been applied to map QTL for growth traits. To identify genes located in QTL responsible for specific traits, genomic large insert libraries are of crucial importance. We reported herein a bacterial artificial chromosome (BAC) library and the mapping of BAC clones to

Chun Ming Wang; Loong Chueng Lo; Felicia Feng; Ping Gong; Jian Li; Ze Yuan Zhu; Grace Lin; Gen Hua Yue

2008-01-01

24

Repetitive Genomic Elements in a European Corn Borer, Ostrinia nubilalis, BAC Library were Indicated by BAC End Sequencing and Development of Sequence Tag Site Markers: Implications for Lepidopteran Genomic Research  

Technology Transfer Automated Retrieval System (TEKTRAN)

The European corn borer, Ostrinia nubilalis, is a serious pest of food, fiber, and biofuel crops in Europe, North America, and Asia, and a model system for insect olfaction and speciation. A bacterial artificial chromosome (BAC) library constructed for O. nubilalis contains 36,864 clones with estim...

25

Integrated and Sequence-Ordered BAC and YAC-Based Physical Maps for the Rat Genome  

Microsoft Academic Search

As part of the effort to sequence the genome of Rattus norvegicus, we constructed a physical map comprised of fingerprinted bacterial artificial chromosome (BAC) clones from the CHORI-230 BAC library. These BAC clones provide ?13-fold redundant coverage of the genome and have been assembled into 376 fingerprint contigs. A yeast artificial chromosome (YAC) map was also constructed and aligned with

Martin Krzywinski; John Wallis; Claudia Gosele; Ian Bosdet; Readman Chiu; Tina Graves; Oliver Hummel; Dan Layman; Carrie Mathewson; Natasja Wye; Baoli Zhu; Derek Albracht; Jennifer Asano; Sarah Barber; Mabel Brown-John; Susanna Chan; Steve Chand; Alison Cloutier; Jonathon Davito; Chris Fjell; Tony Gaige; Detlev Ganten; Noreen Girn; Kurtis Guggenheimer; Heinz Himmelbauer; Thomas Kreitler; Stephen Leach; Darlene Lee; Hans Lehrach; Michael Mayo; Kelly Mead; Teika Olson; Pawan Pandoh; Anna-Liisa Prabhu; Heesun Shin; Simone Tanzer; Jason Thompson; Miranda Tsai; Jason Walker; George Yang; Mandeep Sekhon; LaDeana Hillier; Heike Zimdahl; Andre Marziali; Kazutoyo Osoegawa; Shaying Zhao; Asim Siddiqui; Pieter J. de Jong; Wes Warren; Elaine Mardis; John D. McPherson; Richard Wilson; Norbert Hubner; Steven Jones; Marco Marra; Jacqueline Schein

2004-01-01

26

Creation of BAC genomic resources for cocoa ( Theobroma cacao L.) for physical mapping of RGA containing BAC clones  

Microsoft Academic Search

We have constructed and validated the first cocoa ( Theobroma cacao L.) BAC library, with the aim of developing molecular resources to study the structure and evolution of the genome of this perennial crop. This library contains 36,864 clones with an average insert size of 120 kb, representing approximately ten haploid genome equivalents. It was constructed from the genotype Scavina-6 (Sca-6),

D. Clément; C. Lanaud; X. Sabau; O. Fouet; L. Le Cunff; E. Ruiz; A. M. Risterucci; J. C. Glaszmann; P. Piffanelli

2004-01-01

27

The construction and characteristics of a BAC library for Cucumis sativus L. ‘B10’  

Microsoft Academic Search

Cloning using bacterial artificial chromosomes (BACs) can yield high quality genomic libraries, which are used for the physical\\u000a mapping, identification and isolation of genes, and for gene sequencing. A BAC genomic library was constructed from high molecular\\u000a weight DNA (HMW DNA) obtained from nuclei of the cucumber (Cucumis sativus L. cv. Borszczagowski; B10 line). The DNA was digested with the

Wojciech Gutman; Magdalena Pawe?kowicz; Rafa? Woycicki; Ewa Piszczek; Zbigniew Przybecki

2008-01-01

28

Construction and characterization of a peanut Hin dIII BAC library  

Microsoft Academic Search

Bacterial artificial chromosome (BAC) libraries have been an essential tool for physical analyses of genomes of many crops. We constructed and characterized the first large-insert DNA library for Arachis hypogaea L. The HindIII BAC library contains 182,784 clones; only 5,484 (3%) had no inserts; and the average insert size is 104.05 kb. Chloroplast DNA contamination was very low, only nine clones,

B. Yüksel; A. H. Paterson

2005-01-01

29

End Sequencing and Finger Printing of Human & Mouse BAC Libraries  

SciTech Connect

This project provided for continued end sequencing of existing and new BAC libraries constructed to support human sequencing as well as to initiate BAC end sequencing from the mouse BAC libraries constructed to support mouse sequencing. The clones, the sequences, and the fingerprints are now an available resource for the community at large. Research and development of new metaodologies for BAC end sequencing have reduced costs and increase throughput.

Fraser, C.

2005-09-27

30

A BAC library of the East African haplochromine cichlid fishAstatotilapia burtoni  

Microsoft Academic Search

A BAC library was constructed from Astatotilapia burtoni, a haplochromine cichlid that is found in Lake Tanganyika, East Africa, and its surrounding rivers. The library was generated from genomic DNA of blood cells and comprises 96,768 individual clones. Its median insert size is 150kb and the coverage is expected to represent about 14 genome equivalents. The coverage evaluation was based

Michael Lang; Tsutomu Miyake; Ingo Braasch; Deborah Tinnemore; Nicol Siegel; Walter Salzburger; Chris T. Amemiya; Axel Meyer

2006-01-01

31

Isolation of Specific Clones from Nonarrayed BAC Libraries through Homologous Recombination  

PubMed Central

We have developed a new approach to screen bacterial artificial chromosome (BAC) libraries by recombination selection. To test this method, we constructed an orangutan BAC library using an E. coli strain (DY380) with temperature inducible homologous recombination (HR) capability. We amplified one library segment, induced HR at 42°C to make it recombination proficient, and prepared electrocompetent cells for transformation with a kanamycin cassette to target sequences in the orangutan genome through terminal recombineering homologies. Kanamycin-resistant colonies were tested for the presence of BACs containing the targeted genes by the use of a PCR-assay to confirm the presence of the kanamycin insertion. The results indicate that this is an effective approach for screening clones. The advantage of recombination screening is that it avoids the high costs associated with the preparation, screening, and archival storage of arrayed BAC libraries. In addition, the screening can be conceivably combined with genetic engineering to create knockout and reporter constructs for functional studies.

Nefedov, Mikhail; Carbone, Lucia; Field, Matthew; Schein, Jacquie; de Jong, Pieter J.

2011-01-01

32

Non-gridded library: a new approach for BAC (bacterial artificial chromosome) exploitation in hexaploid wheat (Triticum aestivum)  

PubMed Central

The feasibility of exploiting non-gridded bacterial artificial chromosome (BAC) libraries and some major factors affecting the efficiency of handling such libraries were studied in hexaploid wheat. Even for a bacterial culture containing only 55% recombinants, some 2000 BAC clones with inserts ranging from 45 to 245 kb could be pooled. The pooled BAC clones could be amplified by culturing for up to 6 h without losing any target clones. These results imply that even for hexaploid wheat, which has an extremely large genome, some 250 pools are sufficient for a BAC library that should satisfy many research objectives. This non-gridded strategy would dramatically reduce the cost and make robotic equipment non-essential in exploiting BAC technology. To construct a representative library and to minimise clone competition, thawing and re-freezing ligation mixtures and bacterial cultures should be avoided in BAC library construction and application.

Ma, Zhiying; Weining, Song; Sharp, Peter J.; Liu, Chunji

2000-01-01

33

A BAC-based physical map of the apple genome.  

PubMed

Genome-wide physical mapping is an essential step toward investigating the genetic basis of complex traits as well as pursuing genomics research of virtually all plant and animal species. We have constructed a physical map of the apple genome from a total of 74,281 BAC clones representing approximately 10.5x haploid genome equivalents. The physical map consists of 2702 contigs, and it is estimated to span approximately 927 Mb in physical length. The reliability of contig assembly was evaluated by several methods, including assembling contigs using variable stringencies, assembling contigs using fingerprints from individual libraries, checking consensus maps of contigs, and using DNA markers. Altogether, the results demonstrated that the contigs were properly assembled. The apple genome-wide BAC-based physical map represents the first draft genome sequence not only for any member of the large Rosaceae family, but also for all tree species. This map will play a critical role in advanced genomics research for apple and other tree species, including marker development in targeted chromosome regions, fine-mapping and isolation of genes/QTL, conducting comparative genomics analyses of plant chromosomes, and large-scale genomics sequencing. PMID:17270394

Han, Yuepeng; Gasic, Ksenija; Marron, Brandy; Beever, Jonathan E; Korban, Schuyler S

2007-01-31

34

Construction and sequence sampling of deep-coverage, large-insert BAC libraries for three model lepidopteran species  

Microsoft Academic Search

BACKGROUND: Manduca sexta, Heliothis virescens, and Heliconius erato represent three widely-used insect model species for genomic and fundamental studies in Lepidoptera. Large-insert BAC libraries of these insects are critical resources for many molecular studies, including physical mapping and genome sequencing, but not available to date. RESULTS: We report the construction and characterization of six large-insert BAC libraries for the three

Chengcang Wu; Dina Proestou; Dorothy Carter; Erica Nicholson; Filippe Santos; Shaying Zhao; Hong-Bin Zhang; Marian R Goldsmith

2009-01-01

35

A highly redundant BAC library of Atlantic salmon (Salmo salar): an important tool for salmon projects  

PubMed Central

Background As farming of Atlantic salmon is growing as an aquaculture enterprise, the need to identify the genomic mechanisms for specific traits is becoming more important in breeding and management of the animal. Traits of importance might be related to growth, disease resistance, food conversion efficiency, color or taste. To identify genomic regions responsible for specific traits, genomic large insert libraries have previously proven to be of crucial importance. These large insert libraries can be screened using gene or genetic markers in order to identify and map regions of interest. Furthermore, large-scale mapping can utilize highly redundant libraries in genome projects, and hence provide valuable data on the genome structure. Results Here we report the construction and characterization of a highly redundant bacterial artificial chromosome (BAC) library constructed from a Norwegian aquaculture strain male of Atlantic salmon (Salmo salar). The library consists of a total number of 305 557 clones, in which approximately 299 000 are recombinants. The average insert size of the library is 188 kbp, representing 18-fold genome coverage. High-density filters each consisting of 18 432 clones spotted in duplicates have been produced for hybridization screening, and are publicly available [1]. To characterize the library, 15 expressed sequence tags (ESTs) derived overgos and 12 oligo sequences derived from microsatellite markers were used in hybridization screening of the complete BAC library. Secondary hybridizations with individual probes were performed for the clones detected. The BACs positive for the EST probes were fingerprinted and mapped into contigs, yielding an average of 3 contigs for each probe. Clones identified using genomic probes were PCR verified using microsatellite specific primers. Conclusion Identification of genes and genomic regions of interest is greatly aided by the availability of the CHORI-214 Atlantic salmon BAC library. We have demonstrated the library's ability to identify specific genes and genetic markers using hybridization, PCR and fingerprinting experiments. In addition, multiple fingerprinting contigs indicated a pseudo-tetraploidity of the Atlantic salmon genome. The highly redundant CHORI-214 BAC library is expected to be an important resource for mapping and sequencing of the Atlantic salmon genome.

Thorsen, Jim; Zhu, Baoli; Frengen, Eirik; Osoegawa, Kazutoyo; de Jong, Pieter J; Koop, Ben F; Davidson, William S; H?yheim, Bj?rn

2005-01-01

36

Screening of Sunflower BAC Library for the Identification of Specific BAC Clones  

Microsoft Academic Search

To facilitate molecular cytogenetic research and the integration of cytogenetic and genetic linkage groups of sunflower, one BAC and one BIBAC library from HA 89 with BamHI and HindIII, respectively, were developed. The average insert sizes were estimated to be 140 kb and 137 kb in the BamHI and HindIII libraries, respectively. The combined libraries consist of 192,000 clones and

Jiuhuan Feng; B. A. Vick; C. C. Jan

37

Engineering Adenovirus Genome by Bacterial Artificial Chromosome (BAC) Technology.  

PubMed

Bacterial artificial chromosomes (BACs) are recombinant DNA molecules designed for propagation of large and instable foreign DNA fragment in Escherichia coli. BACs are used in genetics of large DNA viruses such as herpes and baculoviruses for propagation and manipulation of complex genomic regions or even entire viral genomes in one piece. Viral genomes in BACs are ready for the advanced tools of E. coli genetics. These techniques based on homologous or site-specific recombination allow engineering of virtually any kind of genetic changes. In the recent years, BAC technology was also adapted to manipulation of adenovirus genomes and became an effective alternative to traditional genetic engineering of recombinant adenoviruses. PMID:24132484

Ruzsics, Zsolt; Lemnitzer, Frederic; Thirion, Christian

2014-01-01

38

Construction of an 800-kb contig in the near-centromeric region of the rice blast resistance gene Pita? 2 using a highly representative rice BAC library  

Microsoft Academic Search

We constructed a rice Bacterial Artificial Chromosome (BAC) library from green leaf protoplasts of the cultivar Shimokita\\u000a harboring the rice blast resistance gene Pi-ta. The average insert size of 155 kb and the library size of seven genome equivalents make it one of the most comprehensive\\u000a BAC libraries available, and larger than many plant YAC libraries. The library clones were

S. Nakamura; S. Asakawa; N. Ohmido; K. Fukui; N. Shimizu; S. Kawasaki

1997-01-01

39

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

SciTech Connect

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.

Venken, Koen J.T.; Carlson, Joseph W.; Schulze, Karen L.; Pan, Hongling; He, Yuchun; Spokony, Rebecca; Wan, Kenneth H.; Koriabine, Maxim; de Jong, Pieter J.; White, Kevin P.; Bellen, Hugo J.; Hoskins, Roger A.

2009-04-21

40

Distribution of genes and repetitive elements in the Diabrotica virgifera virgifera genome estimated using BAC sequencing.  

PubMed

Feeding damage caused by the western corn rootworm, Diabrotica virgifera virgifera, is destructive to corn plants in North America and Europe where control remains challenging due to evolution of resistance to chemical and transgenic toxins. A BAC library, DvvBAC1, containing 109,486 clones with 104 ± 34.5?kb inserts was created, which has an ~4.56X genome coverage based upon a 2.58?Gb (2.80?pg) flow cytometry-estimated haploid genome size. Paired end sequencing of 1037 BAC inserts produced 1.17?Mb of data (~0.05% genome coverage) and indicated ~9.4 and 16.0% of reads encode, respectively, endogenous genes and transposable elements (TEs). Sequencing genes within BAC full inserts demonstrated that TE densities are high within intergenic and intron regions and contribute to the increased gene size. Comparison of homologous genome regions cloned within different BAC clones indicated that TE movement may cause haplotype variation within the inbred strain. The data presented here indicate that the D. virgifera virgifera genome is large in size and contains a high proportion of repetitive sequence. These BAC sequencing methods that are applicable for characterization of genomes prior to sequencing may likely be valuable resources for genome annotation as well as scaffolding. PMID:22919272

Coates, Brad S; Alves, Analiza P; Wang, Haichuan; Walden, Kimberly K O; French, B Wade; Miller, Nicholas J; Abel, Craig A; Robertson, Hugh M; Sappington, Thomas W; Siegfried, Blair D

2012-08-05

41

Construction of a Festuca pratensis BAC library for map-based cloning in Festulolium substitution lines.  

PubMed

Introgression in Festulolium is a potentially powerful tool to isolate genes for a large number of traits which differ between Festuca pratensis Huds. and Lolium perenne L. Not only are hybrids between the two species fertile, but the two genomes can be distinguished by genomic in situ hybridisation and a high frequency of recombination occurs between homoeologous chromosomes and chromosome segments. By a programme of introgression and a series of backcrosses, L. perenne lines have been produced which contain small F. pratensis substitutions. This material is a rich source of polymorphic markers targeted towards any trait carried on the F. pratensis substitution not observed in the L. perenne background. We describe here the construction of an F. pratensis BAC library, which establishes the basis of a map-based cloning strategy in L. perenne. The library contains 49,152 clones, with an average insert size of 112 kbp, providing coverage of 2.5 haploid genome equivalents. We have screened the library for eight amplified fragment length polymorphism (AFLP) derived markers known to be linked to an F. pratensis gene introgressed into L. perenne and conferring a staygreen phenotype as a consequence of a mutation in primary chlorophyll catabolism. While for four of the markers it was possible to identify bacterial artificial chromosome (BAC) clones, the other four AFLPs were too repetitive to enable reliable identification of locus-specific BACs. Moreover, when the four BACs were partially sequenced, no obvious coding regions could be identified. This contrasted to BACs identified using cDNA sequences, when multiple genes were identified on the same BAC. PMID:15711790

Donnison, Iain S; O'Sullivan, Donal M; Thomas, Ann; Canter, Peter; Moore, Beverley; Armstead, Ian; Thomas, Howard; Edwards, Keith J; King, Ian P

2005-02-12

42

The European sea bass Dicentrarchus labrax genome puzzle: comparative BAC-mapping and low coverage shotgun sequencing  

PubMed Central

Background Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L. (Moronidae, Perciformes, Teleostei) is one of the most important fishes in European marine aquaculture; growing genomic resources put it on its way to serve as an economic model. Results End sequencing of a sea bass genomic BAC-library enabled the comparative mapping of the sea bass genome using the three-spined stickleback Gasterosteus aculeatus genome as a reference. BAC-end sequences (102,690) were aligned to the stickleback genome. The number of mappable BACs was improved using a two-fold coverage WGS dataset of sea bass resulting in a comparative BAC-map covering 87% of stickleback chromosomes with 588 BAC-contigs. The minimum size of 83 contigs covering 50% of the reference was 1.2 Mbp; the largest BAC-contig comprised 8.86 Mbp. More than 22,000 BAC-clones aligned with both ends to the reference genome. Intra-chromosomal rearrangements between sea bass and stickleback were identified. Size distributions of mapped BACs were used to calculate that the genome of sea bass may be only 1.3 fold larger than the 460 Mbp stickleback genome. Conclusions The BAC map is used for sequencing single BACs or BAC-pools covering defined genomic entities by second generation sequencing technologies. Together with the WGS dataset it initiates a sea bass genome sequencing project. This will allow the quantification of polymorphisms through resequencing, which is important for selecting highly performing domesticated fish.

2010-01-01

43

A bacterial artificial chromosome (BAC) library for sunflower, and identification of clones containing genes for putative transmembrane receptors  

Microsoft Academic Search

Sunflower (Helianthus annuus L.) is an economically important oil seed crop with an estimated genome size of 3000 Mb. We have constructed a bacterial artificial chromosome (BAC) library for sunflower, which represents an estimated 4- to 5-fold coverage of the genome. Nuclei isolated from young leaves were used as a source of high-molecular-weight DNA and a partial restriction endonuclease digestion

L. Gentzbittel; A. Abbott; J. Galaud; L. Georgi; F. Fabre; T. Liboz; G. Alibert

2002-01-01

44

Construction of BAC and BIBAC libraries from sunflower and identification of linkage group-specific clones by overgo hybridization.  

PubMed

Complementary BAC and BIBAC libraries were constructed from nuclear DNA of sunflower cultivar HA 89. The BAC library, constructed with BamHI in the pECBAC1 vector, contains 107,136 clones and has an average insert size of 140 kb. The BIBAC library was constructed with HindIII in the plant-transformation-competent binary vector pCLD04541 and contains 84,864 clones, with an average insert size of 137 kb. The two libraries combined contain 192,000 clones and are equivalent to approximately 8.9 haploid genomes of sunflower (3,000 Mb/1C), and provide a greater than 99% probability of obtaining a clone of interest. The frequencies of BAC and BIBAC clones carrying chloroplast or mitochondrial DNA sequences were estimated to be 2.35 and 0.04%, respectively, and insert-empty clones were less than 0.5%. To facilitate chromosome engineering and anchor the sunflower genetic map to its chromosomes, one to three single- or low-copy RFLP markers from each linkage group of sunflower were used to design pairs of overlapping oligonucleotides (overgos). Thirty-six overgos were designed and pooled as probes to screen a subset (5.1x) of the BAC and BIBAC libraries. Of the 36 overgos, 33 (92%) gave at least one positive clone and 3 (8%) failed to hit any clone. As a result, 195 BAC and BIBAC clones representing 19 linkage groups were identified, including 76 BAC clones and 119 BIBAC clones, further verifying the genome coverage and utility of the libraries. These BAC and BIBAC libraries and linkage group-specific clones provide resources essential for comprehensive research of the sunflower genome. PMID:16612648

Feng, Jiuhuan; Vick, Brady A; Lee, Mi-Kyung; Zhang, Hong-Bin; Jan, C C

2006-04-13

45

Fishing for function: zebrafish BAC transgenics for functional genomics  

PubMed Central

Transgenics using bacterial artificial chromosomes (BACs) offers a great opportunity to look at gene regulation in a developing embryo. The modified BAC containing a reporter inserted just before the translational start site of the gene of interest allows for the visualization of spatio-temporal gene expression. Though this method has been used in the mouse model extensively, its utility in zebrafish studies is relatively new. This review aims to look at the utility of making BAC transgenics in zebrafish and its applications in functional genomics. We look at the various methods to modify the BAC, some limitations and what the future holds.

Chatterjee, Sumantra; Lufkin, Thomas

2012-01-01

46

piggyBac transposase tools for genome engineering  

PubMed Central

The transposon piggyBac is being used increasingly for genetic studies. Here, we describe modified versions of piggyBac transposase that have potentially wide-ranging applications, such as reversible transgenesis and modified targeting of insertions. piggyBac is distinguished by its ability to excise precisely, restoring the donor site to its pretransposon state. This characteristic makes piggyBac useful for reversible transgenesis, a potentially valuable feature when generating induced pluripotent stem cells without permanent alterations to genomic sequence. To avoid further genome modification following piggyBac excision by reintegration, we generated an excision competent/integration defective (Exc+Int?) transposase. Our findings also suggest the position of a target DNA–transposase interaction. Another goal of genome engineering is to develop reagents that can guide transgenes to preferred genomic regions. Others have shown that piggyBac transposase can be active when fused to a heterologous DNA-binding domain. An Exc+Int? transposase, the intrinsic targeting of which is defective, might also be a useful intermediate in generating a transposase whose integration activity could be rescued and redirected by fusion to a site-specific DNA-binding domain. We show that fusion to two designed zinc finger proteins rescued the Int? phenotype. Successful guided transgene integration into genomic DNA would have broad applications to gene therapy and molecular genetics. Thus, an Exc+Int? transposase is a potentially useful reagent for genome engineering and provides insight into the mechanism of transposase–target DNA interaction.

Li, Xianghong; Burnight, Erin R.; Cooney, Ashley L.; Malani, Nirav; Brady, Troy; Sander, Jeffry D.; Staber, Janice; Wheelan, Sarah J.; Joung, J. Keith; McCray, Paul B.; Bushman, Frederic D.; Sinn, Patrick L.; Craig, Nancy L.

2013-01-01

47

DaizuBase, an integrated soybean genome database including BAC-based physical maps.  

PubMed

Soybean [Glycine max (L) Merrill] is one of the most important leguminous crops and ranks fourth after to rice, wheat and maize in terms of world crop production. Soybean contains abundant protein and oil, which makes it a major source of nutritious food, livestock feed and industrial products. In Japan, soybean is also an important source of traditional staples such as tofu, natto, miso and soy sauce. The soybean genome was determined in 2010. With its enormous size, physical mapping and genome sequencing are the most effective approaches towards understanding the structure and function of the soybean genome. We constructed bacterial artificial chromosome (BAC) libraries from the Japanese soybean cultivar, Enrei. The end-sequences of approximately 100,000 BAC clones were analyzed and used for construction of a BAC-based physical map of the genome. BLAST analysis between Enrei BAC-end sequences and the Williams82 genome was carried out to increase the saturation of the map. This physical map will be used to characterize the genome structure of Japanese soybean cultivars, to develop methods for the isolation of agronomically important genes and to facilitate comparative soybean genome research. The current status of physical mapping of the soybean genome and construction of database are presented. PMID:23136506

Katayose, Yuichi; Kanamori, Hiroyuki; Shimomura, Michihiko; Ohyanagi, Hajime; Ikawa, Hiroshi; Minami, Hiroshi; Shibata, Michie; Ito, Tomoko; Kurita, Kanako; Ito, Kazue; Tsubokura, Yasutaka; Kaga, Akito; Wu, Jianzhong; Matsumoto, Takashi; Harada, Kyuya; Sasaki, Takuji

2012-02-04

48

Gram negative shuttle BAC vector for heterologous expression of metagenomic libraries  

Microsoft Academic Search

Bacterial artificial chromosome (BAC) vectors enable stable cloning of large DNA fragments from single genomes or microbial assemblages. A novel shuttle BAC vector was constructed that permits replication of BAC clones in diverse Gram-negative species. The “Gram-negative shuttle BAC” vector (pGNS-BAC) uses the F replicon for stable single-copy replication in E. coli and the broad-host-range RK2 mini-replicon for high-copy replication

Kavita S. Kakirde; Jadwiga Wild; Ronald Godiska; David A. Mead; Andrew G. Wiggins; Robert M. Goodman; Waclaw Szybalski; Mark R. Liles

2011-01-01

49

Construction of a Coix BAC library and isolation of the 22 kDa ?-coixin gene cluster.  

PubMed

Coix lacryma-jobi L. (Coix) is a close relative of maize and is considered a valuable genetic resource for crop improvement. Here we report the construction of the first Coix bacterial artificial chromosome (BAC) library using accession PI 324059. This BAC library contains about 230 400 clones with an average insert size of 113 kb, has low organellar DNA contamination, and provides 16.3-fold coverage of the genome. The library was stored in 12 × 96 pools that could be screened with a PCR protocol. Library screening was performed for the 22 kDa ?-coixin gene family. A total of 57 positive pools were identified, and single clones were isolated from 19 of these pools. Based on DNA fingerprinting and Southern blot analysis, these 19 BAC clones form a single contig of about 340 kb in length, indicating that the 22 kDa ?-coixin genes occur in a cluster. These results demonstrated the suitability of this BAC library for gene isolation and comparative genomics studies of the Coix genome. PMID:20924416

Meng, Xiangzong; Huang, Binbin; Zhou, Liangliang; He, Yunxia; Chen, Qi; Yuan, Yiwei; Xu, Zhengkai; Song, Rentao

2010-09-01

50

Genomic tools development for Aquilegia: construction of a BAC-based physical map  

PubMed Central

Background The genus Aquilegia, consisting of approximately 70 taxa, is a member of the basal eudicot lineage, Ranuculales, which is evolutionarily intermediate between monocots and core eudicots, and represents a relatively unstudied clade in the angiosperm phylogenetic tree that bridges the gap between these two major plant groups. Aquilegia species are closely related and their distribution covers highly diverse habitats. These provide rich resources to better understand the genetic basis of adaptation to different pollinators and habitats that in turn leads to rapid speciation. To gain insights into the genome structure and facilitate gene identification, comparative genomics and whole-genome shotgun sequencing assembly, BAC-based genomics resources are of crucial importance. Results BAC-based genomic resources, including two BAC libraries, a physical map with anchored markers and BAC end sequences, were established from A. formosa. The physical map was composed of a total of 50,155 BAC clones in 832 contigs and 3939 singletons, covering 21X genome equivalents. These contigs spanned a physical length of 689.8 Mb (~2.3X of the genome) suggesting the complex heterozygosity of the genome. A set of 197 markers was developed from ESTs induced by drought-stress, or involved in anthocyanin biosynthesis or floral development, and was integrated into the physical map. Among these were 87 genetically mapped markers that anchored 54 contigs, spanning 76.4 Mb (25.5%) across the genome. Analysis of a selection of 12,086 BAC end sequences (BESs) from the minimal tiling path (MTP) allowed a preview of the Aquilegia genome organization, including identification of transposable elements, simple sequence repeats and gene content. Common repetitive elements previously reported in both monocots and core eudicots were identified in Aquilegia suggesting the value of this genome in connecting the two major plant clades. Comparison with sequenced plant genomes indicated a higher similarity to grapevine (Vitis vinifera) than to rice and Arabidopsis in the transcriptomes. Conclusions The A. formosa BAC-based genomic resources provide valuable tools to study Aquilegia genome. Further integration of other existing genomics resources, such as ESTs, into the physical map should enable better understanding of the molecular mechanisms underlying adaptive radiation and elaboration of floral morphology.

2010-01-01

51

Construction and characterization of a BAC library for sunflower ( Helianthus annuus L.)  

Microsoft Academic Search

A bacterial artificial chromosome (BAC) library was constructed using the sunflower (Helianthus annuus L.) restorer line RHA325, which carries the restorer gene Rf1 and the Pl2-gene conferring resistance to downy mildew. High molecular weight DNA was prepared from nuclei using leaf material from two-week old seedlings. The library was constructed using the HindIII site of pBeloBAC11. The current BAC library

Nehir Özdemir; Renate Horn; Wolfgang Friedt

2004-01-01

52

A bacterial artificial chromosome (BAC) library of Malus floribunda 821 and contig construction for positional cloning of the apple scab resistance gene Vf.  

PubMed

The apple scab resistance gene Vf, originating from the wild species Malus floribunda 821, has been incorporated into a wide variety of apple cultivars through a classical breeding program. With the aim of isolating the Vf gene, a bacterial artificial chromosome (BAC) library consisting of 31 584 clones has been constructed from M. floribunda 821. From the analysis of 88 randomly selected BAC clones, the average insert size is estimated at 125 kb. If it is assumed that the genome size of M. floribunda 821 is 769 Mb/haploid, the library represents about 5x haploid genome equivalents. This provides a 99% probability of finding any specific sequence from this library. PCR-based screening of the library has been carried out using eight random genomic sequence-characterized amplified regions (SCARs), chloroplast- and mitochondria-specific SCARs, and 13 high-density Vf-linked SCAR markers. An average of five positive BAC clones per random SCAR has been obtained, whereas less than 1% of BAC clones are derived from the chloroplast or mitochondrial genomes. Most BAC clones identified with Vf-linked SCAR markers are physically linked. Three BAC contigs along the Vf region have been obtained by assembling physically linked BAC clones based on their fingerprints. The overlapping relatedness of BAC clones has been further confirmed by cytogenetic mapping using fiber fluorescence in situ hybridization (fiber-FISH). The M. floribunda 821 BAC library provides a valuable genetic resource not only for map-based cloning of the Vf gene, but also for finding many other important genes for improving the cultivated apple. PMID:11768214

Xu, M; Song, J; Cheng, Z; Jiang, J; Korban, S S

2001-12-01

53

Analysis of BAC end sequences in oak, a keystone forest tree species, providing insight into the composition of its genome  

Microsoft Academic Search

Background  One of the key goals of oak genomics research is to identify genes of adaptive significance. This information may help to\\u000a improve the conservation of adaptive genetic variation and the management of forests to increase their health and productivity.\\u000a Deep-coverage large-insert genomic libraries are a crucial tool for attaining this objective. We report herein the construction\\u000a of a BAC library

Patricia Faivre Rampant; Isabelle Lesur; Clément Boussardon; Frédérique Bitton; Marie-Laure Martin-Magniette; Catherine Bodénčs; Grégoire Le Provost; Hélčne Bergčs; Sylvia Fluch; Antoine Kremer; Christophe Plomion

2011-01-01

54

A bacterial artificial chromosome (BAC) library for sunflower, and identification of clones containing genes for putative transmembrane receptors.  

PubMed

Sunflower (Helianthus annuus L.) is an economically important oil seed crop with an estimated genome size of 3000 Mb. We have constructed a bacterial artificial chromosome (BAC) library for sunflower, which represents an estimated 4- to 5-fold coverage of the genome. Nuclei isolated from young leaves were used as a source of high-molecular-weight DNA and a partial restriction endonuclease digestion protocol was used to cleave the DNA. A random sample of 60 clones indicated an average insert size of 80 kb, implying a 95% probability of recovering any specific sequence of interest. The library was screened with chloroplast DNA probes. Only 0.1% of the clones were identified to be of chloroplast origin, indicating that contamination with organellar DNAs is very low. The utility of the library was evaluated by screening for the presence of genes for putative transmembrane receptors sharing epidermal growth factor (EGF) and integrin-like domains. First, a homologous sunflower EST (HaELP1) was obtained by degenerate RT-PCR cloning, using Arabidopsis thaliana genes (AtELP) as a source of consensus sequences. Three different BACs yielded positive hybridization signals when HaELP1 was used as a probe. BAC subcloning and sequencing demonstrated the presence of two different loci putatively homologous to genes for transmembrane proteins with EGF- and integrin-like domains from sunflower. This work demonstrates the suitability of the library for homology map-based cloning of sunflower genes and physical mapping of the sunflower genome. PMID:11862492

Gentzbittel, L; Abbott, A; Galaud, J P; Georgi, L; Fabre, F; Liboz, T; Alibert, G

2001-12-19

55

Construction of a BAC library and a physical map of a major QTL for CBB resistance of common bean (Phaseolus vulgaris L.).  

PubMed

A major quantitative trait loci (QTL) conditioning common bacterial blight (CBB) resistance in common bean (Phaseolus vulgaris L.) lines HR45 and HR67 was derived from XAN159, a resistant line obtained from an interspecific cross between common bean lines and the tepary bean (P. acutifolius L.) line PI319443. This source of CBB resistance is widely used in bean breeding. Several other CBB resistance QTL have been identified but none of them have been physically mapped. Four molecular markers tightly linked to this QTL have been identified suitable for marker assisted selection and physical mapping of the resistance gene. A bacterial artificial chromosome (BAC) library was constructed from high molecular weight DNA of HR45 and is composed of 33,024 clones. The size of individual BAC clone inserts ranges from 30 kb to 280 kb with an average size of 107 kb. The library is estimated to represent approximately sixfold genome coverage. The BAC library was screened as BAC pools using four PCR-based molecular markers. Two to seven BAC clones were identified by each marker. Two clones were found to have both markers PV-tttc001 and STS183. One preliminary contig was assembled based on DNA finger printing of those positive BAC clones. The minimum tiling path of the contig contains 6 BAC clones spanning an estimated size of 750 kb covering the QTL region. PMID:20419470

Liu, S Y; Yu, K; Huffner, M; Park, S J; Banik, M; Pauls, K P; Crosby, W

2010-04-25

56

Direct targeting and rapid isolation of BAC clones spanning a defined chromosome region  

Microsoft Academic Search

To isolate genes of interest in plants, it is essential to construct bacterial artificial chromosome (BAC) libraries from specific genotypes. Construction and organisation of BAC libraries is laborious and costly, especially from organisms with large and complex genomes. In the present study, we developed the pooled BAC library strategy that allows rapid and low cost generation and screening of genomic

Edwige Isidore; Beatrice Scherrer; Arnaud Bellec; Karine Budin; Patricia Faivre-Rampant; Robbie Waugh; Beat Keller; Michel Caboche; Catherine Feuillet; Boulos Chalhoub

2005-01-01

57

CONSTRUCTION OF BAC AND BIBAC LIBRARIES FROM SUNFLOWER AND IDENTIFICATION OF LINKAGE GROUP-SPECIFIC CLONES BY OVERGO HYBRIDIZATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two complementary BAC and BIBAC libraries were constructed from nuclear DNA of sunflower cultivar HA 89. The BAC library was constructed with BamHI in the pECBAC1 vector. It contains 107,136 clones and has an average insert size of 140 kb. The BIBAC library was constructed with HindIII in the plant-...

58

BAC end sequencing of Pacific white shrimp Litopenaeus vannamei: a glimpse into the genome of Penaeid shrimp  

NASA Astrophysics Data System (ADS)

Little is known about the genome of Pacific white shrimp ( Litopenaeus vannamei). To address this, we conducted BAC (bacterial artificial chromosome) end sequencing of L. vannamei. We selected and sequenced 7 812 BAC clones from the BAC library LvHE from the two ends of the inserts by Sanger sequencing. After trimming and quality filtering, 11 279 BAC end sequences (BESs) including 4 609 pairedends BESs were obtained. The total length of the BESs was 4 340 753 bp, representing 0.18% of the L. vannamei haploid genome. The lengths of the BESs ranged from 100 bp to 660 bp with an average length of 385 bp. Analysis of the BESs indicated that the L. vannamei genome is AT-rich and that the primary repeats patterns were simple sequence repeats (SSRs) and low complexity sequences. Dinucleotide and hexanucleotide repeats were the most common SSR types in the BESs. The most abundant transposable element was gypsy, which may contribute to the generation of the large genome size of L. vannamei. We successfully annotated 4 519 BESs by BLAST searching, including genes involved in immunity and sex determination. Our results provide an important resource for functional gene studies, map construction and integration, and complete genome assembly for this species.

Zhao, Cui; Zhang, Xiaojun; Liu, Chengzhang; Huan, Pin; Li, Fuhua; Xiang, Jianhai; Huang, Chao

2012-05-01

59

Construction and Preliminary Characterization Analysis of Wuzhishan Miniature Pig Bacterial Artificial Chromosome Library with Approximately 8-Fold Genome Equivalent Coverage  

PubMed Central

Bacterial artificial chromosome (BAC) libraries have been invaluable tools for the genome-wide genetic dissection of complex organisms. Here, we report the construction and characterization of a high-redundancy BAC library from a very valuable pig breed in China, Wuzhishan miniature pig (Sus scrofa), using its blood cells and fibroblasts, respectively. The library contains approximately 153,600 clones ordered in 40 superpools of 10 × 384-deep well microplates. The average insert size of BAC clones was estimated to be 152.3?kb, representing approximately 7.68 genome equivalents of the porcine haploid genome and a 99.93% statistical probability of obtaining at least one clone containing a unique DNA sequence in the library. 19 pairs of microsatellite marker primers covering porcine chromosomes were used for screening the BAC library, which showed that each of these markers was positive in the library; the positive clone number was 2 to 9, and the average number was 7.89, which was consistent with 7.68-fold coverage of the porcine genome. And there were no significant differences of genomic BAC library from blood cells and fibroblast cells. Therefore, we identified 19 microsatellite markers that could potentially be used as genetic markers. As a result, this BAC library will serve as a valuable resource for gene identification, physical mapping, and comparative genomics and large-scale genome sequencing in the porcine.

Liu, Changqing; Guo, Yuo; Lu, Taofeng; Wu, Hongmei; Na, Risu; Li, Xiangchen; Guan, Weijun; Ma, Yuehui

2013-01-01

60

Generation and Screening of a BAC Library from a Diploid Potato Clone to Unravel Durable Late Blight Resistance on Linkage Group IV  

PubMed Central

We describe the construction and screening of a large insert genomic library from the diploid potato clone HB171(13) that has been shown to express durable quantitative field resistance to Phytophthora infestans, the causal agent of potato late blight disease. Integrated genetic mapping of the field resistance quantitative trait locus with markers developed from populations segregating for Rpi-blb3, Rpi-abpt, R2, and R2-like resistance, all located on linkage group IV, has positioned the field resistance QTL within the proximity of this R gene cluster. The library has been successfully screened with resistance gene analogues (RGA) potentially linked to the R gene cluster. Over 30 positive BAC clones were identified and confirmed by PCR and Southern hybridisations to harbour RGA-like sequences. In addition, BAC end sequencing of positive clones has corroborated two BAC clones with a very high level of nucleotide similarity to the RGA probes utilised.

Hein, Ingo; McLean, Karen; Chalhoub, Boulos; Bryan, Glenn J.

2007-01-01

61

Genome-wide end-sequenced BAC resources for the NOD/MrkTac? and NOD/ShiLtJ?? mouse genomes  

PubMed Central

Non-obese diabetic (NOD) mice spontaneously develop type 1 diabetes (T1D) due to the progressive loss of insulin-secreting ?-cells by an autoimmune driven process. NOD mice represent a valuable tool for studying the genetics of T1D and for evaluating therapeutic interventions. Here we describe the development and characterization by end-sequencing of bacterial artificial chromosome (BAC) libraries derived from NOD/MrkTac (DIL NOD) and NOD/ShiLtJ (CHORI-29), two commonly used NOD substrains. The DIL NOD library is composed of 196,032 BACs and the CHORI-29 library is composed of 110,976 BACs. The average depth of genome coverage of the DIL NOD library, estimated from mapping the BAC end-sequences to the reference mouse genome sequence, was 7.1-fold across the autosomes and 6.6-fold across the X chromosome. Clones from this library have an average insert size of 150 kb and map to over 95.6% of the reference mouse genome assembly (NCBIm37), covering 98.8% of Ensembl mouse genes. By the same metric, the CHORI-29 library has an average depth over the autosomes of 5.0-fold and 2.8-fold coverage of the X chromosome, the reduced X chromosome coverage being due to the use of a male donor for this library. Clones from this library have an average insert size of 205 kb and map to 93.9% of the reference mouse genome assembly, covering 95.7% of Ensembl genes. We have identified and validated 191,841 single nucleotide polymorphisms (SNPs) for DIL NOD and 114,380 SNPs for CHORI-29. In total we generated 229,736,133 bp of sequence for the DIL NOD and 121,963,211 bp for the CHORI-29. These BAC libraries represent a powerful resource for functional studies, such as gene targeting in NOD embryonic stem (ES) cell lines, and for sequencing and mapping experiments.

Steward, Charles A.; Humphray, Sean; Plumb, Bob; Jones, Matthew C.; Quail, Michael A.; Rice, Stephen; Cox, Tony; Davies, Rob; Bonfield, James; Keane, Thomas M.; Nefedov, Michael; de Jong, Pieter J.; Lyons, Paul; Wicker, Linda; Todd, John; Hayashizaki, Yoshihide; Gulban, Omid; Danska, Jayne; Harrow, Jen; Hubbard, Tim; Rogers, Jane; Adams, David J.

2010-01-01

62

Comparative BAC-based mapping in the white-throated sparrow, a novel behavioral genomics model, using interspecies overgo hybridization  

PubMed Central

Background The genomics era has produced an arsenal of resources from sequenced organisms allowing researchers to target species that do not have comparable mapping and sequence information. These new "non-model" organisms offer unique opportunities to examine environmental effects on genomic patterns and processes. Here we use comparative mapping as a first step in characterizing the genome organization of a novel animal model, the white-throated sparrow (Zonotrichia albicollis), which occurs as white or tan morphs that exhibit alternative behaviors and physiology. Morph is determined by the presence or absence of a complex chromosomal rearrangement. This species is an ideal model for behavioral genomics because the association between genotype and phenotype is absolute, making it possible to identify the genomic bases of phenotypic variation. Findings We initiated a genomic study in this species by characterizing the white-throated sparrow BAC library via filter hybridization with overgo probes designed for the chicken, turkey, and zebra finch. Cross-species hybridization resulted in 640 positive sparrow BACs assigned to 77 chicken loci across almost all macro-and microchromosomes, with a focus on the chromosomes associated with morph. Out of 216 overgos, 36% of the probes hybridized successfully, with an average number of 3.0 positive sparrow BACs per overgo. Conclusions These data will be utilized for determining chromosomal architecture and for fine-scale mapping of candidate genes associated with phenotypic differences. Our research confirms the utility of interspecies hybridization for developing comparative maps in other non-model organisms.

2011-01-01

63

Development of cell lines from the sheep used to construct the CHORI-243 ovine BAC library  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two cell lines, designated MARC.OVSM and MARC.OKF, were initiated from the aorta and kidney, respectively, obtained from the Texel ram used to make the CHORI-243 Ovine BAC library. These cell lines have been submitted to the NIA Aging Cell Repository at the Coriell Cell Respositories, Camden, NJ, U...

64

Genome-wide identification of genes conferring energy related resistance to a synthetic antimicrobial peptide (Bac8c).  

PubMed

A fundamental issue in the design and development of antimicrobials is the lack of understanding of complex modes of action and how this complexity affects potential pathways for resistance evolution. Bac8c (RIWVIWRR-NH(2)) is an 8 amino acid antimicrobial peptide (AMP) that has been shown to have enhanced activity against a range of pathogenic Gram-positive and Gram-negative bacteria, as well as yeast. We have previously demonstrated that Bac8c appears to interfere with multiple targets, at least in part through the disruption of cytoplasmic membrane related functions, and that resistance to this peptide does not easily develop using standard laboratory methods. Here, we applied a genomics approach, SCalar Analysis of Library Enrichement (SCALEs), to map the effect of gene overexpression onto Bac8c resistance in parallel for all genes and gene combinations (up to ? 10 adjacent genes) in the E. coli genome (a total of ? 500,000 individual clones were mapped). Our efforts identified an elaborate network of genes for which overexpression leads to low-level resistance to Bac8c (including biofilm formation, multi-drug transporters, etc). This data was analyzed to provide insights into the complex relationships between mechanisms of action and potential routes by which resistance to this synthetic AMP can develop. PMID:23383054

Spindler, Eileen C; Boyle, Nanette R; Hancock, Robert E W; Gill, Ryan T

2013-01-31

65

Construction of BAC and BIBAC libraries from sunflower and identification of linkage group-specific clones by overgo hybridization  

Microsoft Academic Search

Complementary BAC and BIBAC libraries were constructed from nuclear DNA of sunflower cultivar HA 89. The BAC library, constructed with BamHI in the pECBAC1 vector, contains 107,136 clones and has an average insert size of 140 kb. The BIBAC library was constructed with HindIII in the plant-transformation-competent binary vector pCLD04541 and contains 84,864 clones, with an average insert size of 137 kb.

Jiuhuan Feng; Brady A. Vick; Mi-Kyung Lee; Hong-Bin Zhang; C. C. Jan

2006-01-01

66

Hemi-nested touchdown PCR combined with primer-template mismatch PCR for rapid isolation and sequencing of low molecular weight glutenin subunit gene family from a hexaploid wheat BAC library  

Microsoft Academic Search

BACKGROUND: Hexaploid wheat (Triticum aestivum L.) possesses a large genome that contains 1.6 × 1010 bp of DNA. Isolation of a large number of gene sequences from complex gene families with a high level of gene sequence identity from genomic DNA is therefore difficult and time-consuming. Bacterial artificial chromosome (BAC) libraries can be useful for such work. Here we report

Xiu-Qiang Huang; Sylvie Cloutier

2007-01-01

67

Isolation of high molecular weight DNA from marine sponge bacteria for BAC library construction.  

PubMed

Metagenomics is a powerful tool for mining the genetic repositories from environmental microorganisms. Bacteria associated with marine sponges (phylum Porifera) are rich sources of biologically active natural products. However, to date, few compounds are discovered from the sponge metagenomic libraries, and the main reason might be the difficulties in recovery of high molecular weight (HMW) DNA from sponge symbionts to construct large insert libraries. Here, we describe a method to recover HMW bacterial DNA from diverse sponges with high quality for bacterial artificial chromosome (BAC) library construction. Microorganisms concentrated from sponges by differential centrifugation were embedded in agarose plugs to lyse out the HMW DNA for recovery. DNA fragments over 436 kb size were recovered from three different types of sponges, Halichondria sp., Haliclona sp., and Xestospongia sp. To evaluate the recovered DNA quality, the diversity of bacterial DNA comprised in the HMW DNA derived from sponge Halichondria sp. was analyzed, and this HMW DNA sample was also cloned into a shuttle BAC vector between Escherichia coli and Streptomyces sp. The results showed that more than five types of bacterial DNA, i.e., Proteobacteria, Nitrospirae, Cyanobacteria, Planctomycetes, and unidentified bacteria, had been recovered by this method, and an average 100 kb size insert DNA in a constructed BAC library demonstrated that the recovered HMW DNA is suitable for metagenomic library construction. PMID:19685098

Ouyang, Yongchang; Dai, Shikun; Xie, Lianwu; Ravi Kumar, M S; Sun, Wei; Sun, Huimin; Tang, Danling; Li, Xiang

2009-08-15

68

SOYBEAN BAC CONTIGS ANCHORED WITH RFLPS: INSIGHTS INTO GENOME DUPLICATION AND GENE CLUSTERING  

Technology Transfer Automated Retrieval System (TEKTRAN)

Surveying the soybean genome with 683 bacterial artificial chromosome (BAC) contiguous groups ('contigs') anchored by restriction fragment length polymorphisms (RFLPs) enabled us to explore microsyntenic relationships among duplicated regions, and also to examine the physical organization of hypomet...

69

Association and in silico assignment of sequences from turkey BACs.  

PubMed

Bacterial artificial chromosomes (BACs) provide an important resource in genetic mapping. An initial set of BACs corresponding to microsatellite markers in the turkey (Meleagris gallopavo) was isolated from the CHORI-260 turkey BAC library. The selected markers were distributed on both macro- and microchromosomes and included a genetically unlinked marker. End sequences were obtained for a subset of the recovered BACs and compared to the chicken whole genome sequence. Close association of the turkey BAC-end sequences and original marker sequences was generally conserved in the chicken genome. Gene content of the turkey BACs is predicted from the comparative sequence alignments. PMID:18432398

Reed, Kent M; Faile, Gretchen M; Kreuth, Stacy B; Chaves, Lee D; Sullivan, Laura M

2008-01-01

70

Insights into the Loblolly Pine Genome: Characterization of BAC and Fosmid Sequences  

PubMed Central

Despite their prevalence and importance, the genome sequences of loblolly pine, Norway spruce, and white spruce, three ecologically and economically important conifer species, are just becoming available to the research community. Following the completion of these large assemblies, annotation efforts will be undertaken to characterize the reference sequences. Accurate annotation of these ancient genomes would be aided by a comprehensive repeat library; however, few studies have generated enough sequence to fully evaluate and catalog their non-genic content. In this paper, two sets of loblolly pine genomic sequence, 103 previously assembled BACs and 90,954 newly sequenced and assembled fosmid scaffolds, were analyzed. Together, this sequence represents 280 Mbp (roughly 1% of the loblolly pine genome) and one of the most comprehensive studies of repetitive elements and genes in a gymnosperm species. A combination of homology and de novo methodologies were applied to identify both conserved and novel repeats. Similarity analysis estimated a repetitive content of 27% that included both full and partial elements. When combined with the de novo investigation, the estimate increased to almost 86%. Over 60% of the repetitive sequence consists of full or partial LTR (long terminal repeat) retrotransposons. Through de novo approaches, 6,270 novel, full-length transposable element families and 9,415 sub-families were identified. Among those 6,270 families, 82% were annotated as single-copy. Several of the novel, high-copy families are described here, with the largest, PtPiedmont, comprising 133 full-length copies. In addition to repeats, analysis of the coding region reported 23 full-length eukaryotic orthologous proteins (KOGS) and another 29 novel or orthologous genes. These discoveries, along with other genomic resources, will be used to annotate conifer genomes and address long-standing questions about gymnosperm evolution.

Dougherty, William M.; Martinez-Garcia, Pedro J.; Koriabine, Maxim; Holtz-Morris, Ann; deJong, Pieter; Crepeau, Marc; Langley, Charles H.; Puiu, Daniela; Salzberg, Steven L.; Neale, David B.; Stevens, Kristian A.

2013-01-01

71

Construction and Characterization of a Human Bacterial Artificial Chromosome Library  

Microsoft Academic Search

We have constructed an arrayed human genomic BAC library with approximately 4× coverage that is represented by 96,000 BAC clones with average insert size of nearly 140 kb. A new BAC vector that allows color-based positive screening to identify transformants with inserts has increased BAC cloning efficiency. The library was gridded onto hybridization filters at high density for efficient identification

Ung-Jin Kim; Bruce W. Birren; Tatiana Slepak; Valeria Mancino; Cecilie Boysen; Hyung-Lyun Kang; Melvin I. Simon; Hiroaki Shizuya

1996-01-01

72

Comparative analysis of copy number detection by whole-genome BAC and oligonucleotide array CGH  

PubMed Central

Background Microarray-based comparative genomic hybridization (aCGH) is a powerful diagnostic tool for the detection of DNA copy number gains and losses associated with chromosome abnormalities, many of which are below the resolution of conventional chromosome analysis. It has been presumed that whole-genome oligonucleotide (oligo) arrays identify more clinically significant copy-number abnormalities than whole-genome bacterial artificial chromosome (BAC) arrays, yet this has not been systematically studied in a clinical diagnostic setting. Results To determine the difference in detection rate between similarly designed BAC and oligo arrays, we developed whole-genome BAC and oligonucleotide microarrays and validated them in a side-by-side comparison of 466 consecutive clinical specimens submitted to our laboratory for aCGH. Of the 466 cases studied, 67 (14.3%) had a copy-number imbalance of potential clinical significance detectable by the whole-genome BAC array, and 73 (15.6%) had a copy-number imbalance of potential clinical significance detectable by the whole-genome oligo array. However, because both platforms identified copy number variants of unclear clinical significance, we designed a systematic method for the interpretation of copy number alterations and tested an additional 3,443 cases by BAC array and 3,096 cases by oligo array. Of those cases tested on the BAC array, 17.6% were found to have a copy-number abnormality of potential clinical significance, whereas the detection rate increased to 22.5% for the cases tested by oligo array. In addition, we validated the oligo array for detection of mosaicism and found that it could routinely detect mosaicism at levels of 30% and greater. Conclusions Although BAC arrays have faster turnaround times, the increased detection rate of oligo arrays makes them attractive for clinical cytogenetic testing.

2010-01-01

73

Construction and characterization of a soybean bacterial artificial chromosome library and use of multiple complementary libraries for genome physical mapping  

Microsoft Academic Search

Two plant-transformation-competent large-insert binary clone bacterial artificial chromosome (hereafter BIBAC) libraries were previously constructed for soybean cv. Forrest, using BamHI or HindIII. However, they are not well suited for clone-based genomic sequencing due to their larger ratio of vector to insert size (27.6 kbp:125 kbp). Therefore, we developed a larger-insert bacterial artificial chromosome (BAC) library for the genotype in a smaller vector

C.-C. Wu; P. Nimmakayala; F. A. Santos; R. Springman; C. Scheuring; K. Meksem; D. A. Lightfoot; H.-B. Zhang

2004-01-01

74

The complexity of Rhipicephalus (Boophilus) microplus genome characterised through detailed analysis of two BAC clones  

PubMed Central

Background Rhipicephalus (Boophilus) microplus (Rmi) a major cattle ectoparasite and tick borne disease vector, impacts on animal welfare and industry productivity. In arthropod research there is an absence of a complete Chelicerate genome, which includes ticks, mites, spiders, scorpions and crustaceans. Model arthropod genomes such as Drosophila and Anopheles are too taxonomically distant for a reference in tick genomic sequence analysis. This study focuses on the de-novo assembly of two R. microplus BAC sequences from the understudied R microplus genome. Based on available R. microplus sequenced resources and comparative analysis, tick genomic structure and functional predictions identify complex gene structures and genomic targets expressed during tick-cattle interaction. Results In our BAC analyses we have assembled, using the correct positioning of BAC end sequences and transcript sequences, two challenging genomic regions. Cot DNA fractions compared to the BAC sequences confirmed a highly repetitive BAC sequence BM-012-E08 and a low repetitive BAC sequence BM-005-G14 which was gene rich and contained short interspersed elements (SINEs). Based directly on the BAC and Cot data comparisons, the genome wide frequency of the SINE Ruka element was estimated. Using a conservative approach to the assembly of the highly repetitive BM-012-E08, the sequence was de-convoluted into three repeat units, each unit containing an 18S, 5.8S and 28S ribosomal RNA (rRNA) encoding gene sequence (rDNA), related internal transcribed spacer and complex intergenic region. In the low repetitive BM-005-G14, a novel gene complex was found between to 2 genes on the same strand. Nested in the second intron of a large 9 Kb papilin gene was a helicase gene. This helicase overlapped in two exonic regions with the papilin. Both these genes were shown expressed in different tick life stage important in ectoparasite interaction with the host. Tick specific sequence differences were also determined for the papilin gene and the protein binding sites of the 18S subunit in a comparison to Bos taurus. Conclusion In the absence of a sequenced reference genome we have assembled two complex BAC sequences, characterised novel gene structure that was confirmed by gene expression and sequencing analyses. This is the first report to provide evidence for 2 eukaryotic genes with exon regions that overlap on the same strand, the first to describe Rhipicephalinae papilin, and the first to report the complete ribosomal DNA repeated unit sequence structure for ticks. The Cot data estimation of genome wide sequence frequency means this research will underpin future efforts for genome sequencing and assembly of the R. microplus genome.

2011-01-01

75

Technology at Washington University School of Medicine Library: BACS, PHILSOM, and OCTANET.  

PubMed

A brief overview of the Bibliographic Access and Control System developed by the Washington University School of Medicine Library is presented. Because the system has been described in two previous reports, this paper focuses on its relationship to other automated programs (i.e., PHILSOM and OCTANET), education of users, evaluation of the system, and outreach to the medical center. In operation for more than two years, BACS represents the computerization of much of the managerial and operational functions of the library, and marks the completion of stage 1 of the three stages of library evolution described in the AAMC report Academic Information in the Academic Health Sciences Center: Roles for the Library in Information Management. PMID:6688750

Crawford, S; Johnson, M F; Kelly, E A

1983-07-01

76

Assembly and sorting of homologous BAC contigs in allotetraploid cotton genomes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Upland cotton (G. hirsutum) is a diploidized allopolyploid species containing At and Dt sub-genomes that have partial homology. Assembly and sorting of homologous BAC contigs into their subgenomes and further to individual chromosomes are of both great interest and great challenge for genome-wide i...

77

Analysis Of Papaya BAC End Sequences: Insights Into The Organization Of A Tree Fruit Genome  

Technology Transfer Automated Retrieval System (TEKTRAN)

Papaya (Carica papaya L.) is a major tree fruit crop of tropical and subtropical regions with an estimated genome size of 372 Mbp. We present the analysis of 4.7% of the papaya genome based on BAC end sequences (BESs) representing 17 million high-quality bases. Microsatellites discovered in 5,452 BE...

78

piggyBac is an effective tool for functional analysis of the Plasmodium falciparum genome  

PubMed Central

Background Much of the Plasmodium falciparum genome encodes hypothetical proteins with limited homology to other organisms. A lack of robust tools for genetic manipulation of the parasite limits functional analysis of these hypothetical proteins and other aspects of the Plasmodium genome. Transposon mutagenesis has been used widely to identify gene functions in many organisms and would be extremely valuable for functional analysis of the Plasmodium genome. Results In this study, we investigated the lepidopteran transposon, piggyBac, as a molecular genetic tool for functional characterization of the Plasmodium falciparum genome. Through multiple transfections, we generated 177 unique P. falciparum mutant clones with mostly single piggyBac insertions in their genomes. Analysis of piggyBac insertion sites revealed random insertions into the P. falciparum genome, in regards to gene expression in parasite life cycle stages and functional categories. We further explored the possibility of forward genetic studies in P. falciparum with a phenotypic screen for attenuated growth, which identified several parasite genes and pathways critical for intra-erythrocytic development. Conclusion Our results clearly demonstrate that piggyBac is a novel, indispensable tool for forward functional genomics in P. falciparum that will help better understand parasite biology and accelerate drug and vaccine development.

2009-01-01

79

An overview of the apple genome through BAC end sequence analysis.  

PubMed

The apple, Malus x domestica Borkh., is one of the most important fruit trees grown worldwide. A bacterial artificial chromosome (BAC)-based physical map of the apple genome has been recently constructed. Based on this physical map, a total of approximately 2,100 clones from different contigs (overlapping BAC clones) have been selected and sequenced at both ends, generating 3,744 high-quality BAC end sequences (BESs) including 1,717 BAC end pairs. Approximately 8.5% of BESs contain simple sequence repeats (SSRs), most of which are AT/TA dimer repeats. Potential transposable elements are identified in approximately 21% of BESs, and most of these elements are retrotransposons. About 11% of BESs have homology to the Arabidopsis protein database. The matched proteins cover a broad range of categories. The average GC content of the predicted coding regions of BESs is 42.4%; while, that of the whole BESs is 39%. A small number of BES pairs were mapped to neighboring chromosome regions of A. thaliana and Populus trichocarpa; whereas, no pairs are mapped to the Oryza sativa genome. The apple has a higher degree of synteny with the closely related Populus than with the distantly related Arabidopsis. BAC end sequencing can be used to anchor a small proportion of the apple genome to the Populus and possibly to the Arabidopsis genomes. PMID:18521706

Han, Yuepeng; Korban, Schuyler S

2008-06-03

80

Genomic insight into the common carp (Cyprinus carpio) genome by sequencing analysis of BAC-end sequences  

PubMed Central

Background Common carp is one of the most important aquaculture teleost fish in the world. Common carp and other closely related Cyprinidae species provide over 30% aquaculture production in the world. However, common carp genomic resources are still relatively underdeveloped. BAC end sequences (BES) are important resources for genome research on BAC-anchored genetic marker development, linkage map and physical map integration, and whole genome sequence assembling and scaffolding. Result To develop such valuable resources in common carp (Cyprinus carpio), a total of 40,224 BAC clones were sequenced on both ends, generating 65,720 clean BES with an average read length of 647 bp after sequence processing, representing 42,522,168 bp or 2.5% of common carp genome. The first survey of common carp genome was conducted with various bioinformatics tools. The common carp genome contains over 17.3% of repetitive elements with GC content of 36.8% and 518 transposon ORFs. To identify and develop BAC-anchored microsatellite markers, a total of 13,581 microsatellites were detected from 10,355 BES. The coding region of 7,127 genes were recognized from 9,443 BES on 7,453 BACs, with 1,990 BACs have genes on both ends. To evaluate the similarity to the genome of closely related zebrafish, BES of common carp were aligned against zebrafish genome. A total of 39,335 BES of common carp have conserved homologs on zebrafish genome which demonstrated the high similarity between zebrafish and common carp genomes, indicating the feasibility of comparative mapping between zebrafish and common carp once we have physical map of common carp. Conclusion BAC end sequences are great resources for the first genome wide survey of common carp. The repetitive DNA was estimated to be approximate 28% of common carp genome, indicating the higher complexity of the genome. Comparative analysis had mapped around 40,000 BES to zebrafish genome and established over 3,100 microsyntenies, covering over 50% of the zebrafish genome. BES of common carp are tremendous tools for comparative mapping between the two closely related species, zebrafish and common carp, which should facilitate both structural and functional genome analysis in common carp.

2011-01-01

81

Comparative analysis of copy number detection by whole-genome BAC and oligonucleotide array CGH  

Microsoft Academic Search

BACKGROUND: Microarray-based comparative genomic hybridization (aCGH) is a powerful diagnostic tool for the detection of DNA copy number gains and losses associated with chromosome abnormalities, many of which are below the resolution of conventional chromosome analysis. It has been presumed that whole-genome oligonucleotide (oligo) arrays identify more clinically significant copy-number abnormalities than whole-genome bacterial artificial chromosome (BAC) arrays, yet this

Nicholas J Neill; Beth S Torchia; Bassem A Bejjani; Lisa G Shaffer; Blake C Ballif

2010-01-01

82

BacMap: an interactive picture atlas of annotated bacterial genomes.  

PubMed

BacMap is an interactive visual database containing fully labeled, zoomable and searchable chromosome maps from more than 170 bacterial (archaebacterial and eubacterial) species. It uses a recently developed visualization tool (CGView) to generate high-resolution circular genome maps from sequence feature information. Each map includes an interface that allows the image to be expanded and rotated. In the default view, identified genes are drawn to scale and colored according to coding directions. When a region of interest is expanded, gene labels are displayed. Each label is hyperlinked to a custom 'gene card' which provides several fields of information concerning the corresponding DNA and protein sequences. Each genome map is searchable via a local BLAST search and a gene name/synonym search. BacMap is freely available at http://wishart.biology.ualberta.ca/BacMap/. PMID:15608206

Stothard, Paul; Van Domselaar, Gary; Shrivastava, Savita; Guo, Anchi; O'Neill, Brian; Cruz, Joseph; Ellison, Michael; Wishart, David S

2005-01-01

83

Chromosomal mapping of canine-derived BAC clones to the red fox and American mink genomes.  

PubMed

High-quality sequencing of the dog (Canis lupus familiaris) genome has enabled enormous progress in genetic mapping of canine phenotypic variation. The red fox (Vulpes vulpes), another canid species, also exhibits a wide range of variation in coat color, morphology, and behavior. Although the fox genome has not yet been sequenced, canine genomic resources have been used to construct a meiotic linkage map of the red fox genome and begin genetic mapping in foxes. However, a more detailed gene-specific comparative map between the dog and fox genomes is required to establish gene order within homologous regions of dog and fox chromosomes and to refine breakpoints between homologous chromosomes of the 2 species. In the current study, we tested whether canine-derived gene-containing bacterial artificial chromosome (BAC) clones can be routinely used to build a gene-specific map of the red fox genome. Forty canine BAC clones were mapped to the red fox genome by fluorescence in situ hybridization (FISH). Each clone was uniquely assigned to a single fox chromosome, and the locations of 38 clones agreed with cytogenetic predictions. These results clearly demonstrate the utility of FISH mapping for construction of a whole-genome gene-specific map of the red fox. The further possibility of using canine BAC clones to map genes in the American mink (Mustela vison) genome was also explored. Much lower success was obtained for this more distantly related farm-bred species, although a few BAC clones were mapped to the predicted chromosomal locations. PMID:19546120

Kukekova, Anna V; Vorobieva, Nadegda V; Beklemisheva, Violetta R; Johnson, Jennifer L; Temnykh, Svetlana V; Yudkin, Dmitry V; Trut, Lyudmila N; Andre, Catherine; Galibert, Francis; Aguirre, Gustavo D; Acland, Gregory M; Graphodatsky, Alexander S

2009-06-21

84

Identification and characterization of piggyBac -like elements in the genome of domesticated silkworm, Bombyx mori  

Microsoft Academic Search

piggyBac is a short inverted terminal repeat (ITR) transposable element originally discovered in Trichoplusia ni. It is currently the preferred vector of choice for enhancer trapping, gene discovery and identifying gene function in insects and mammals. Many piggyBac-like sequences have been found in the genomes of phylogenetically species from fungi to mammals. We have identified 98 piggyBac-like sequences (BmPBLE1-98) from

Han-Fu Xu; Qing-You Xia; Chun Liu; Ting-Cai Cheng; Ping Zhao; Jun Duan; Xing-Fu Zha; Shi-Ping Liu

2006-01-01

85

A Bacterial Artificial Chromosome Library for Sequencing the Complete Human Genome  

Microsoft Academic Search

A 30-fold redundant human bacterial artificial chromosome (BAC) library with a large average insert size (178 kb) has been constructed to provide the intermediate substrate for the international genome sequencing effort. The DNA was obtained from a single anonymous volunteer, whose identity was protected through a double-blind donor selection protocol. DNA fragments were generated by partial digestion with EcoRI (library

Kazutoyo Osoegawa; Aaron G. Mammoser; Chenyan Wu; Eirik Frengen; Changjiang Zeng; Joseph J. Catanese; Pieter J. de Jong

2007-01-01

86

Mobilization of giant piggyBac transposons in the mouse genome  

PubMed Central

The development of technologies that allow the stable delivery of large genomic DNA fragments in mammalian systems is important for genetic studies as well as for applications in gene therapy. DNA transposons have emerged as flexible and efficient molecular vehicles to mediate stable cargo transfer. However, the ability to carry DNA fragments >10?kb is limited in most DNA transposons. Here, we show that the DNA transposon piggyBac can mobilize 100-kb DNA fragments in mouse embryonic stem (ES) cells, making it the only known transposon with such a large cargo capacity. The integrity of the cargo is maintained during transposition, the copy number can be controlled and the inserted giant transposons express the genomic cargo. Furthermore, these 100-kb transposons can also be excised from the genome without leaving a footprint. The development of piggyBac as a large cargo vector will facilitate a wider range of genetic and genomic applications.

Li, Meng Amy; Turner, Daniel J.; Ning, Zemin; Yusa, Kosuke; Liang, Qi; Eckert, Sabine; Rad, Lena; Fitzgerald, Tomas W.; Craig, Nancy L.; Bradley, Allan

2011-01-01

87

Mobilization of giant piggyBac transposons in the mouse genome.  

PubMed

The development of technologies that allow the stable delivery of large genomic DNA fragments in mammalian systems is important for genetic studies as well as for applications in gene therapy. DNA transposons have emerged as flexible and efficient molecular vehicles to mediate stable cargo transfer. However, the ability to carry DNA fragments >10 kb is limited in most DNA transposons. Here, we show that the DNA transposon piggyBac can mobilize 100-kb DNA fragments in mouse embryonic stem (ES) cells, making it the only known transposon with such a large cargo capacity. The integrity of the cargo is maintained during transposition, the copy number can be controlled and the inserted giant transposons express the genomic cargo. Furthermore, these 100-kb transposons can also be excised from the genome without leaving a footprint. The development of piggyBac as a large cargo vector will facilitate a wider range of genetic and genomic applications. PMID:21948799

Li, Meng Amy; Turner, Daniel J; Ning, Zemin; Yusa, Kosuke; Liang, Qi; Eckert, Sabine; Rad, Lena; Fitzgerald, Tomas W; Craig, Nancy L; Bradley, Allan

2011-09-24

88

Generation of the first BAC-based physical map of the common carp genome  

PubMed Central

Background Common carp (Cyprinus carpio), a member of Cyprinidae, is the third most important aquaculture species in the world with an annual global production of 3.4 million metric tons, accounting for nearly 14% of the all freshwater aquaculture production in the world. Apparently genomic resources are needed for this species in order to study its performance and production traits. In spite of much progress, no physical maps have been available for common carp. The objective of this project was to generate a BAC-based physical map using fluorescent restriction fingerprinting. Result The first generation of common carp physical map was constructed using four- color High Information Content Fingerprinting (HICF). A total of 72,158 BAC clones were analyzed that generated 67,493 valid fingerprints (5.5 × genome coverage). These BAC clones were assembled into 3,696 contigs with the average length of 476 kb and a N50 length of 688 kb, representing approximately 1.76 Gb of the common carp genome. The largest contig contained 171 BAC clones with the physical length of 3.12 Mb. There are 761 contigs longer than the N50, and these contigs should be the most useful resource for future integrations with linkage map and whole genome sequence assembly. The common carp physical map is available at http://genomics.cafs.ac.cn/fpc/WebAGCoL/Carp/WebFPC/. Conclusion The reported common carp physical map is the first physical map of the common carp genome. It should be a valuable genome resource facilitating whole genome sequence assembly and characterization of position-based genes important for aquaculture traits.

2011-01-01

89

A versatile, highly efficient, and potentially safer piggyBac transposon system for mammalian genome manipulations.  

PubMed

The piggyBac transposon is one of the most attractive nonviral tools for mammalian genome manipulations. Given that piggybac mobilizes in a "cut-and-paste" fashion, integrant remobilization could potentially damage the host genome. Here, we report a novel piggyBac transposon system with a series of recombinant transposases. We found that the transposition activity of wild-type (PBase) and hyperactive (hyPBase) piggyBac transposases can be significantly increased by peptide fusions in a cell-type dependent fashion, with the greatest change typically seen in mouse embryonic stem (ES) cells. The two most potent recombinant transposases, TPLGMH and ThyPLGMH, give a 9- and 7-fold increase, respectively, in the number of integrants in HEK293 compared with Myc-tagged PBase (MycPBase), and both display 4-fold increase in generating induced pluripotential stem cells. Interestingly, ThyPLGMH but not TPLGMH shows improved chromosomal excision activity (2.5-fold). This unique feature of TPLGMH provides the first evidence that integration activity of a transposase can be drastically improved without increasing its remobilization activity. Transposition catalyzed by ThyPLGMH is more random and occurs further from CpG islands than that catalyzed by MycPBase or TPLGMH. Our transposon system diversifies the mammalian genetic toolbox and provides a spectrum of piggyBac transposases that is better suited to different experimental purposes.-Meir, Y.-J. J., Lin, A., Huang, M.-F., Lin, J.-R., Weirauch, M. T., Chou, H.-C., Lin, S.-J., Wu, S. C. A versatile, highly efficient, and potentially safer piggyBac transposon system for mammalian genome manipulations. PMID:23896728

Meir, Yaa-Jyuhn James; Lin, Angelique; Huang, Meng-Fan; Lin, Jiao-Rung; Weirauch, Matthew T; Chou, Hsiang-Chen; Lin, Siang-Jin Ashley; Wu, Sareina Chiung-Yuan

2013-07-29

90

Self-excision of the BAC sequences from the recombinant Marek's disease virus genome increases replication and pathogenicity  

Microsoft Academic Search

Cloning of full length genomes of herpesviruses as bacterial artificial chromosomes (BAC) has greatly facilitated the manipulation of the genomes of several herpesviruses to identify the pathogenic determinants. We have previously reported the construction of the BAC clone (pRB-1B5) of the highly oncogenic Marek's disease virus (MDV) strain RB-1B, which has proven to be a valuable resource for elucidating several

Yuguang Zhao; Lawrence Petherbridge; Lorraine P Smith; Sue Baigent; Venugopal Nair

2008-01-01

91

Gene content and density in banana ( Musa acuminata ) as revealed by genomic sequencing of BAC clones  

Microsoft Academic Search

The complete sequence of Musa acuminata bacterial artificial chromosome (BAC) clones is presented and, consequently, the first analysis of the banana genome organization. One clone (MuH9) is 82,723 bp long with an overall G+C content of 38.2%. Twelve putative protein-coding sequences were identified, representing a gene density of one per 6.9 kb, which is slightly less than that previously reported for Arabidopsis

R. Aert; L. Sági; G. Volckaert

2004-01-01

92

BacMap: an up-to-date electronic atlas of annotated bacterial genomes.  

PubMed

Originally released in 2005, BacMap is an electronic, interactive atlas of fully sequenced bacterial genomes. It contains fully labeled, zoomable and searchable chromosome maps for essentially all sequenced prokaryotic (archaebacterial and eubacterial) species. Each map can be zoomed to the level of individual genes and each gene is hyperlinked to a richly annotated gene card. The latest release of BacMap (http://bacmap.wishartlab.com/) now contains data for more than 1700 bacterial species (~10× more than the 2005 release), corresponding to more than 2800 chromosome and plasmid maps. All bacterial genome maps are now supplemented with separate prophage genome maps as well as separate tRNA and rRNA maps. Each bacterial chromosome entry in BacMap also contains graphs and tables on a variety of gene and protein statistics. Likewise, every bacterial species entry contains a bacterial 'biography' card, with taxonomic details, phenotypic details, textual descriptions and images (when available). Improved data browsing and searching tools have also been added to allow more facile filtering, sorting and display of the chromosome maps and their contents. PMID:22135301

Cruz, Joseph; Liu, Yifeng; Liang, Yongjie; Zhou, You; Wilson, Michael; Dennis, Jonathan J; Stothard, Paul; Van Domselaar, Gary; Wishart, David S

2011-12-01

93

CONSTRUCTION OF A SUGARBEET BAC LIBRARY FROM A HYBRID THAT COMBINES DIVERSE TRAITS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A Bacterial Artificial Chromosome library with five-fold coverage of the ca. 750 Mb sugar beet genome was constructed from HinDIII-digested DNA from hybrid USH20, with an average insert size of 100 to 125 kb. Filter arrays were prepared that contained all clones and were used to assess the abundanc...

94

UTILIZATION AND CHARACTERIZATION OF THE NCCCWA RAINBOW TROUT BAC LIBRARY FOR PHYSICAL AND LINKAGE MAPPING  

Technology Transfer Automated Retrieval System (TEKTRAN)

A 10X rainbow trout bacterial artificial chromosome library was constructed by Amplicon Express for the National Center for Cool and Cold Water Aquaculture (NCCCWA) primarily to aid in the physical and genetic mapping efforts of the rainbow trout genome. Dr. Gary Thorgaard of Washington State Univer...

95

Using comparative genomics to reorder the human genome sequence into a virtual sheep genome  

Microsoft Academic Search

BACKGROUND: Is it possible to construct an accurate and detailed subgene-level map of a genome using bacterial artificial chromosome (BAC) end sequences, a sparse marker map, and the sequences of other genomes? RESULTS: A sheep BAC library, CHORI-243, was constructed and the BAC end sequences were determined and mapped with high sensitivity and low specificity onto the frameworks of the

Brian P Dalrymple; Ewen F Kirkness; Mikhail Nefedov; Sean McWilliam; Abhirami Ratnakumar; Wes Barris; Shaying Zhao; Jyoti Shetty; Jillian F Maddox; Margaret O'Grady; Frank Nicholas; Allan M Crawford; Tim Smith; Pieter J de Jong; John McEwan; V Hutton Oddy; Noelle E Cockett

2007-01-01

96

A first generation BAC-based physical map of the rainbow trout genome  

PubMed Central

Background Rainbow trout (Oncorhynchus mykiss) are the most-widely cultivated cold freshwater fish in the world and an important model species for many research areas. Coupling great interest in this species as a research model with the need for genetic improvement of aquaculture production efficiency traits justifies the continued development of genomics research resources. Many quantitative trait loci (QTL) have been identified for production and life-history traits in rainbow trout. A bacterial artificial chromosome (BAC) physical map is needed to facilitate fine mapping of QTL and the selection of positional candidate genes for incorporation in marker-assisted selection (MAS) for improving rainbow trout aquaculture production. This resource will also facilitate efforts to obtain and assemble a whole-genome reference sequence for this species. Results The physical map was constructed from DNA fingerprinting of 192,096 BAC clones using the 4-color high-information content fingerprinting (HICF) method. The clones were assembled into physical map contigs using the finger-printing contig (FPC) program. The map is composed of 4,173 contigs and 9,379 singletons. The total number of unique fingerprinting fragments (consensus bands) in contigs is 1,185,157, which corresponds to an estimated physical length of 2.0 Gb. The map assembly was validated by 1) comparison with probe hybridization results and agarose gel fingerprinting contigs; and 2) anchoring large contigs to the microsatellite-based genetic linkage map. Conclusion The production and validation of the first BAC physical map of the rainbow trout genome is described in this paper. We are currently integrating this map with the NCCCWA genetic map using more than 200 microsatellites isolated from BAC end sequences and by identifying BACs that harbor more than 300 previously mapped markers. The availability of an integrated physical and genetic map will enable detailed comparative genome analyses, fine mapping of QTL, positional cloning, selection of positional candidate genes for economically important traits and the incorporation of MAS into rainbow trout breeding programs.

Palti, Yniv; Luo, Ming-Cheng; Hu, Yuqin; Genet, Carine; You, Frank M; Vallejo, Roger L; Thorgaard, Gary H; Wheeler, Paul A; Rexroad, Caird E

2009-01-01

97

An improved method for extracting bacteria from soil for high molecular weight DNA recovery and BAC library construction  

Microsoft Academic Search

Separation of bacterial cells from soil is a key step in the construction of metagenomic BAC libraries with large DNA inserts.\\u000a Our results showed that when combined with sodium pyro-phosphate and homogenization for soil dispersion, sucrose density gradient\\u000a centrifugation (SDGC) was more effective at separating bacteria from soil than was low speed centrifugation (LSC). More than\\u000a 70% of the cells,

Juan Liu; Jingquan Li; Li Feng; Hui Cao; Zhongli Cui

2010-01-01

98

Structural analysis of MHC alleles in an RSV tumour regression chicken using a BAC library.  

PubMed

The chicken major histocompatibility complex (MHC-B locus) has a strong association with resistance and susceptibility to numerous diseases. We have found a B haplotype designated WLA that associated with the regression of tumours caused by Rous sarcoma virus J strain (RSV-J). Haplotype WLA was identical to the regressive B6 haplotype when partial genotyping was performed (Poultry Science, 89, 2010, 651). We then constructed a bacterial artificial chromosome (BAC) library from a WLA homozygote chicken to evaluate the structure of this regression haplotype and compared it to those of the B6 haplotype. Comparison between WLA and B6 above 59 kb within the 167 kb, including 14 genes from BG1 to BF2, revealed 75 SNPs and 14 indels. However, several genes were identical between WLA and B6, including the BF1 and BF2 genes, which encode a class I molecule previously suggested to be related to the regression phenotype. The BLB2 gene encoding the MHC class II beta chain showed the greatest diversity, with 19 non-synonymous SNPs. A comparison of WLA and B6 haplotpyes that are associated with tumour regression and RIRa and B24 haplotypes associated with tumour progression suggests that DMA1, DMA2, BRD2, TAPBP and BLB2 genes are not involved in the intensity of RSV J tumour regression. PMID:22486511

Suzuki, K; Kobayashi, E; Yamashita, H; Uenishi, H; Churkina, I; Plastow, G; Hamasima, N; Mitsuhashi, T

2011-08-15

99

A plant-transformation-competent BIBAC library from the Arabidopsis thaliana Landsberg ecotype for functional and comparative genomics  

Microsoft Academic Search

The genome of the model plant Arabidopsis thaliana has been sequenced to near completion. To facilitate experimental determination of the function of every gene in the species, we constructed a large-insert library from the Landsberg ecotype using a plant-transformation-competent binary BAC vector, BIBAC2. The library contains 11,520 clones with an estimated average insert size of 162 kb. Of a sample

Y.-L. Chang; X. Henriquez; D. Preuss; G. Copenhaver; H.-B. Zhang

2003-01-01

100

Genome-wide BAC-end sequencing of Musa acuminata DH Pahang reveals further insights into the genome organization of banana  

Microsoft Academic Search

Banana and plantain (Musa spp.) are grown in more than 120 countries in tropical and subtropical regions and constitute an important staple food for\\u000a millions of people. A Musa acuminata ssp. malaccencis DH Pahang bacterial artificial chromosome (BAC) library (MAMB) was submitted for BAC-end sequencing. MAMB consists of 23,040\\u000a clones, with a 140-kbp average insert size, accounting for a five

Rafael E. Arango; Roberto C. Togawa; Sebastien C. Carpentier; Nicolas Roux; Bas L. Hekkert; Gert H. J. Kema; Manoel T. Souza Jr

2011-01-01

101

Localization and Characterization of 170 BAC-derived clones and mapping of Ninety-Four Microsatellites in the Hessian Fly  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ninety-four microsatellites from enriched genomic libraries of Hessian fly (Mayetiola destructor (Say)) were localized to 170 cognate clones in a Hessian fly bacterial artificial chromosome (BAC) library. These microsatellite-positive BAC clones were physically mapped to polytene chromosomes by fl...

102

Self-excision of the BAC sequences from the recombinant Marek's disease virus genome increases replication and pathogenicity  

PubMed Central

Cloning of full length genomes of herpesviruses as bacterial artificial chromosomes (BAC) has greatly facilitated the manipulation of the genomes of several herpesviruses to identify the pathogenic determinants. We have previously reported the construction of the BAC clone (pRB-1B5) of the highly oncogenic Marek's disease virus (MDV) strain RB-1B, which has proven to be a valuable resource for elucidating several oncogenic determinants. Despite the retention of the BAC replicon within the genome, the reconstituted virus was able to induce tumours in susceptible chickens. Nevertheless, it was unclear whether the presence of the BAC influenced the full oncogenic potential of the reconstituted virus. To maximize the closeness of BAC-derived virus to the parental RB-1B strain, we modified the existing pRB-1B5 clone by restoring the Us2 and by introducing SV40-cre cassette within the loxP sites of the mini-F plasmid, to allow self-excision of the plasmid sequences in chicken cells. The reconstituted virus from the modified clone showed significant improvement in replication in vitro and in vivo. Excision of the BAC sequences also enhanced the pathogenicity to levels similar to that of the parental virus, as the cumulative incidence of Marek's disease in groups infected with the recombinant and the parental viruses showed no significant differences. Thus, we have been able to make significant improvements to the existing BAC clone of this highly oncogenic virus which would certainly increase its usefulness as a valuable tool for studies on identifying the oncogenic determinants of this major avian pathogen.

Zhao, Yuguang; Petherbridge, Lawrence; Smith, Lorraine P; Baigent, Sue; Nair, Venugopal

2008-01-01

103

Analysis of papaya BAC end sequences reveals first insights into the organization of a fruit tree genome  

Microsoft Academic Search

Papaya (Carica papaya L.) is a major tree fruit crop of tropical and subtropical regions with an estimated genome size of 372 Mbp. We present the analysis of 4.7% of the papaya genome based on BAC end sequences (BESs) representing 17 million high-quality bases. Microsatellites discovered in 5,452 BESs and flanking primer sequences are available to papaya breeding programs at http:\\/\\/www.genomics.hawaii.edu\\/papaya\\/BES. Sixteen

Chun Wan J. Lai; Qingyi Yu; Shaobin Hou; Rachel L. Skelton; Meghan R. Jones; Kanako L. T. Lewis; Jan Murray; Moriah Eustice; Peizhu Guan; Ricelle Agbayani; Paul H. Moore; Ray Ming; Gernot G. Presting

2006-01-01

104

Construction of bacterial artificial chromosome libraries and their application in developing PCR-based markers closely linked to a major locus conditioning bruchid resistance in mungbean ( Vigna radiata L. Wilczek)  

Microsoft Academic Search

Bacterial artificial chromosome (BAC) libraries have been widely used in different aspects of genome research. In this paper we report the construction of the first mungbean (Vigna radiata L. Wilczek) BAC libraries. These BAC clones were obtained from two ligations and represent an estimated 3.5 genome equivalents. This correlated well with the screening of nine random single-copy restriction fragment length

M. Miyagi; M. Humphry; Z. Y. Ma; C. J. Lambrides; M. Bateson; C. J. Liu

2004-01-01

105

Construction, characterization and preliminary BAC-end sequencing analysis of a bacterial artificial chromosome library of white clover (Trifolium repens L.)  

Technology Transfer Automated Retrieval System (TEKTRAN)

White clover (Trifolium repens L.) is a forage legume widely used in combination with grass in pastures due to its ability for nitrogen fixation. We have constructed a bacterial artificial chromosome (BAC) library of an advanced breeding line of white clover. The library contains 37,248 clones wit...

106

Multicolor chromosome banding (MCB) with YAC/BAC-based probes and region-specific microdissection DNA libraries  

SciTech Connect

Multicolor chromosome banding (MCB) allows the delineation of chromosomal regions with a resolution of a few mega base pairs, i.e., slightly below the size of most visible chromosome bands. Based on the hybridization of over lapping region-specific probe libraries, chromosomal subregions are hybridized with probes that fluoresce in distinct wave length intervals, so they can be assigned predefined pseudo-colors during the digital imaging and visualization process. The present study demonstrates how MCB patterns can be produced by region-specific micro dissection derived (mcd) libraries as well as collections of yeast or bacterial artificial chromosomes (YACs and BACs, respectively). We compared the efficiency of an mcd library based approach with the hybridization of collections of locus-specific probes (LSP) for fluorescent banding of three rather differently sized human chromosomes, i.e., chromosomes 2, 13, and 22. The LSP sets were comprised of 107 probes specific for chromosome 2, 82 probes for chromosome 13, and 31 probes for chromosome 22. The results demonstrated a more homogeneous coverage of chromosomes and thus, more desirable banding patterns using the microdissection library-based MCB. This may be related to the observation that chromosomes are difficult to cover completely with YAC and/or BAC clones as single-color fluorescence in situ hybridization (FISH) experiments showed. Mcd libraries, on the other hand, provide high complexity probes that work well as region specific paints, but do not readily allow positioning of break points on genetic or physical maps as required for the positional cloning of genes. Thus, combinations of mcd libraries and locus-specific large insert DNA probes appear to be the most efficient tools for high-resolution cytogenetic analyses.

Liehr, T.; Weise, A.; Heller, A.; Starke, H.; Mrasek, K.; Kuechler, A.; Weier, H.-U.G.; Claussen, U.

2003-06-23

107

[Integration sites and their characteristic analysis of piggyBac transposon in cattle genome].  

PubMed

As a useful tool for genetic engineering, piggyBac (PB) transposons have been widely used in more than one species of transgenosis or generating mutation studies. At present, the studies about PB transposons in cattle were few. In order to get the PB transposon integration sites and summarize its characteristics in bovine genome, donor plasmid of PB[CMV-EGFP] and helper-dependent plasmid of pcDNA-PBase were constructed and transferred into bovine fibroblasts by Amaxa basic nucleofector kit for primary mammalian fibroblasts. Cell clones stably transfected were obtained after screening by G-418. Genomic DNA of transgenic cells was extracted and the integration sites of PB transposon were detected by genome walking technology. Eight integration sites were obtained in bovine genome, although only 5 sites were mapped on chromosomes 1, 2, 11, and X chromosome. We found that PB transposon was inserted into the "TTAA" location and integrated into the intergenic non-regulatory sites between two genes. Analysis of the composition of the five bases, which was close to the side of the PB integration sites "TTAA", showed that PB 5' tended to be inserted into region rich in GC (62.5%). From the study, we got that transposition occurred in cattle genome by PB transposons and the integration site information acquired from the research will provide theoretical references for bovine study by PB transposon. PMID:23774022

Du, Xin-Hua; Gao, Xue; Zhang, Lu-Pei; Gao, Hui-Jiang; Li, Jun-Ya; Xu, Shang-Zhong

2013-06-01

108

BAC library resources for map-based cloning and physical map construction in barley ( Hordeum vulgare L.)  

Microsoft Academic Search

Background  Although second generation sequencing (2GS) technologies allow re-sequencing of previously gold-standard-sequenced genomes,\\u000a whole genome shotgun sequencing and de novo assembly of large and complex eukaryotic genomes is still difficult. Availability of a genome-wide physical map is therefore\\u000a still a prerequisite for whole genome sequencing for genomes like barley. To start such an endeavor, large insert genomic\\u000a libraries, i.e. Bacterial Artificial

Daniela Schulte; Ruvini Ariyadasa; Bujun Shi; Delphine Fleury; Chris Saski; Michael Atkins; Pieter deJong; Cheng-Cang Wu; Andreas Graner; Peter Langridge; Nils Stein

2011-01-01

109

Sequencing, annotation and comparative analysis of nine BACs of giant panda ( Ailuropoda melanoleuca )  

Microsoft Academic Search

A 10-fold BAC library for giant panda was constructed and nine BACs were selected to generate finish sequences. These BACs\\u000a could be used as a validation resource for the de novo assembly accuracy of the whole genome shotgun sequencing reads of giant panda newly generated by the Illumina GA sequencing\\u000a technology. Complete sanger sequencing, assembly, annotation and comparative analysis were

Yang Zheng; Jing Cai; JianWen Li; Bo Li; Runmao Lin; Feng Tian; XiaoLing Wang; Jun Wang

2010-01-01

110

A bacterial artificial chromosome library for the Australian saltwater crocodile (Crocodylus porosus) and its utilization in gene isolation and genome characterization  

PubMed Central

Background Crocodilians (Order Crocodylia) are an ancient vertebrate group of tremendous ecological, social, and evolutionary importance. They are the only extant reptilian members of Archosauria, a monophyletic group that also includes birds, dinosaurs, and pterosaurs. Consequently, crocodilian genomes represent a gateway through which the molecular evolution of avian lineages can be explored. To facilitate comparative genomics within Crocodylia and between crocodilians and other archosaurs, we have constructed a bacterial artificial chromosome (BAC) library for the Australian saltwater crocodile, Crocodylus porosus. This is the first BAC library for a crocodile and only the second BAC resource for a crocodilian. Results The C. porosus BAC library consists of 101,760 individually archived clones stored in 384-well microtiter plates. NotI digestion of random clones indicates an average insert size of 102 kb. Based on a genome size estimate of 2778 Mb, the library affords 3.7 fold (3.7×) coverage of the C. porosus genome. To investigate the utility of the library in studying sequence distribution, probes derived from CR1a and CR1b, two crocodilian CR1-like retrotransposon subfamilies, were hybridized to C. porosus macroarrays. The results indicate that there are a minimum of 20,000 CR1a/b elements in C. porosus and that their distribution throughout the genome is decidedly non-random. To demonstrate the utility of the library in gene isolation, we probed the C. porosus macroarrays with an overgo designed from a C-mos (oocyte maturation factor) partial cDNA. A BAC containing C-mos was identified and the C-mos locus was sequenced. Nucleotide and amino acid sequence alignment of the C. porosus C-mos coding sequence with avian and reptilian C-mos orthologs reveals greater sequence similarity between C. porosus and birds (specifically chicken and zebra finch) than between C. porosus and squamates (green anole). Conclusion We have demonstrated the utility of the Crocodylus porosus BAC library as a tool in genomics research. The BAC library should expedite complete genome sequencing of C. porosus and facilitate detailed analysis of genome evolution within Crocodylia and between crocodilians and diverse amniote lineages including birds, mammals, and other non-avian reptiles.

2009-01-01

111

PiggyMac, a domesticated piggyBac transposase involved in programmed genome rearrangements in the ciliate Paramecium tetraurelia  

PubMed Central

Programmed genome rearrangements drive functional gene assembly in ciliates during the development of the somatic macronucleus. The elimination of germline sequences is directed by noncoding RNAs and is initiated by DNA double-strand breaks, but the enzymes responsible for DNA cleavage have not been identified. We show here that PiggyMac (Pgm), a domesticated piggyBac transposase, is required for these rearrangements in Paramecium tetraurelia. A GFP-Pgm fusion localizes in developing macronuclei, where rearrangements take place, and RNAi-mediated silencing of PGM abolishes DNA cleavage. This is the first in vivo evidence suggesting an essential endonucleolytic function of a domesticated piggyBac transposase.

Baudry, Celine; Malinsky, Sophie; Restituito, Matthieu; Kapusta, Aurelie; Rosa, Sarah; Meyer, Eric; Betermier, Mireille

2009-01-01

112

Genome-wide target profiling of piggyBac and Tol2 in HEK 293: pros and cons for gene discovery and gene therapy  

PubMed Central

Background DNA transposons have emerged as indispensible tools for manipulating vertebrate genomes with applications ranging from insertional mutagenesis and transgenesis to gene therapy. To fully explore the potential of two highly active DNA transposons, piggyBac and Tol2, as mammalian genetic tools, we have conducted a side-by-side comparison of the two transposon systems in the same setting to evaluate their advantages and disadvantages for use in gene therapy and gene discovery. Results We have observed that (1) the Tol2 transposase (but not piggyBac) is highly sensitive to molecular engineering; (2) the piggyBac donor with only the 40 bp 3'-and 67 bp 5'-terminal repeat domain is sufficient for effective transposition; and (3) a small amount of piggyBac transposases results in robust transposition suggesting the piggyBac transpospase is highly active. Performing genome-wide target profiling on data sets obtained by retrieving chromosomal targeting sequences from individual clones, we have identified several piggyBac and Tol2 hotspots and observed that (4) piggyBac and Tol2 display a clear difference in targeting preferences in the human genome. Finally, we have observed that (5) only sites with a particular sequence context can be targeted by either piggyBac or Tol2. Conclusions The non-overlapping targeting preference of piggyBac and Tol2 makes them complementary research tools for manipulating mammalian genomes. PiggyBac is the most promising transposon-based vector system for achieving site-specific targeting of therapeutic genes due to the flexibility of its transposase for being molecularly engineered. Insights from this study will provide a basis for engineering piggyBac transposases to achieve site-specific therapeutic gene targeting.

2011-01-01

113

Construction and Characterization of Two Bacterial Artificial Chromosome Libraries of Grass Carp  

Microsoft Academic Search

Bacterial artificial chromosome (BAC) library is an important tool in genomic research. We constructed two libraries from\\u000a the genomic DNA of grass carp (Ctenopharyngodon idellus) as a crucial part of the grass carp genome project. The libraries were constructed in the EcoRI and HindIII sites of the vector CopyControl pCC1BAC. The EcoRI library comprised 53,000 positive clones, and approximately 99.94%

Songhun Jang; Hang Liu; Jianguo Su; Feng Dong; Feng Xiong; Lanjie Liao; Yaping Wang; Zuoyan Zhu

2010-01-01

114

A bacterial artificial chromosome (BAC) library of Malus floribunda 821 and contig construction for positional cloning of the apple scab resistance gene Vf  

Microsoft Academic Search

The apple scab resistance gene Vf, originating from the wild species Malus floribunda 821, has been incorporated into a wide variety of apple cultivars through a classical breeding program. With the aim of isolating the Vf gene, a bacterial artificial chromosome (BAC) library consisting of 31 584 clones has been constructed from M. floribunda 821. From the analysis of 88

Mingliang Xu; Junqi Song; Zhukuan Cheng; Jiming Jiang; Schuyler S. Korban

2001-01-01

115

CONSTRUCTION OF A HEXAPLOID WHEAT (TRITICUM AESTIVUM L.) BACTERIAL ARTIFICIAL CHROMOSOME LIBRARY AND IDENTIFICATION OF CANDIDATE BAC CLONES CONTAINING STRIPE RUST RESISTANCE GENE MARKERS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A hexaploid wheat (Triticum astivum L.) bacterial artificial chromosome (BAC) library was constructed for the positional cloning of the wheat strip rust resistance gene Yr5. The Yr5 near-isogenic line were used to isolate the high molecular weight DNA as intact nuclei. The HindIII partial restrict...

116

Construction of two BAC libraries from cucumber ( Cucumis sativus L.) and identification of clones linked to yield component quantitative trait loci  

Microsoft Academic Search

Two bacterial artificial chromosome (BAC) libraries were constructed from an inbred line derived from a cultivar of cucumber (Cucumis sativus L.). Intact nuclei were isolated and embedded in agarose plugs, and high-molecular-weight DNA was subsequently partially digested with BamHI or EcoRI. Ligation of double size-selected DNA fragments with the pECBAC1 vector yielded two libraries containing 23,040 BamHI and 18,432 EcoRI

Y.-W. Nam; J.-R. Lee; K.-H. Song; M.-K. Lee; M. D. Robbins; S.-M. Chung; J. E. Staub; H.-B. Zhang

2005-01-01

117

A hyperactive piggyBac transposase for mammalian applications  

PubMed Central

DNA transposons have been widely used for transgenesis and insertional mutagenesis in various organisms. Among the transposons active in mammalian cells, the moth-derived transposon piggyBac is most promising with its highly efficient transposition, large cargo capacity, and precise repair of the donor site. Here we report the generation of a hyperactive piggyBac transposase. The active transposition of piggyBac in multiple organisms allowed us to screen a transposase mutant library in yeast for hyperactive mutants and then to test candidates in mouse ES cells. We isolated 18 hyperactive mutants in yeast, among which five were also hyperactive in mammalian cells. By combining all mutations, a total of 7 aa substitutions, into a single reading frame, we generated a unique hyperactive piggyBac transposase with 17-fold and ninefold increases in excision and integration, respectively. We showed its applicability by demonstrating an increased efficiency of generation of transgene-free mouse induced pluripotent stem cells. We also analyzed whether this hyperactive piggyBac transposase affects the genomic integrity of the host cells. The frequency of footprints left by the hyperactive piggyBac transposase was as low as WT transposase (~1%) and we found no evidence that the expression of the transposase affects genomic integrity. This hyperactive piggyBac transposase expands the utility of the piggyBac transposon for applications in mammalian genetics and gene therapy.

Yusa, Kosuke; Zhou, Liqin; Li, Meng Amy; Bradley, Allan; Craig, Nancy L.

2011-01-01

118

Utilization of super BAC pools and Fluidigm access array platform for high-throughput BAC clone identification: proof of concept.  

PubMed

Bacterial artificial chromosome (BAC) libraries are critical for identifying full-length genomic sequences, correlating genetic and physical maps, and comparative genomics. Here we describe the utilization of the Fluidigm access array genotyping system in conjunction with KASPar genotyping technology to identify individual BAC clones corresponding to specific single-nucleotide polymorphisms (SNPs) from an Amplicon Express seven-plate super pooled Amaranthus hypochondriacus BAC library. Ninety-six SNP loci, spanning the length of A. hypochondriacus linkage groups 1, 2, and 15, were simultaneously tested for clone identification from four BAC super pools, corresponding to 28 384-well plates, using a single Fluidigm integrated fluidic chip (IFC). Forty-six percent of the SNPs were associated with a single unambiguous identified BAC clone. PCR amplification and next-generation sequencing of individual BAC clones confirmed the IFC clone identification. Utilization of the Fluidigm Dynamic array platform allowed for the simultaneous PCR screening of 10,752?BAC pools for 96?SNP tag sites in less than three hours at a cost of ~$0.05 per reaction. PMID:22910714

Maughan, Peter J; Smith, Scott M; Raney, Joshua A

2012-07-15

119

Transposon Invasion of the Paramecium Germline Genome Countered by a Domesticated PiggyBac Transposase and the NHEJ Pathway.  

PubMed

Sequences related to transposons constitute a large fraction of extant genomes, but insertions within coding sequences have generally not been tolerated during evolution. Thanks to their unique nuclear dimorphism and to their original mechanism of programmed DNA elimination from their somatic nucleus (macronucleus), ciliates are emerging model organisms for the study of the impact of transposable elements on genomes. The germline genome of the ciliate Paramecium, located in its micronucleus, contains thousands of short intervening sequences, the IESs, which interrupt 47% of genes. Recent data provided support to the hypothesis that an evolutionary link exists between Paramecium IESs and Tc1/mariner transposons. During development of the macronucleus, IESs are excised precisely thanks to the coordinated action of PiggyMac, a domesticated piggyBac transposase, and of the NHEJ double-strand break repair pathway. A PiggyMac homolog is also required for developmentally programmed DNA elimination in another ciliate, Tetrahymena. Here, we present an overview of the life cycle of these unicellular eukaryotes and of the developmentally programmed genome rearrangements that take place at each sexual cycle. We discuss how ancient domestication of a piggyBac transposase might have allowed Tc1/mariner elements to spread throughout the germline genome of Paramecium, without strong counterselection against insertion within genes. PMID:22888464

Dubois, Emeline; Bischerour, Julien; Marmignon, Antoine; Mathy, Nathalie; Régnier, Vinciane; Bétermier, Mireille

2012-07-22

120

Construction and Characterization of a Bovine Bacterial Artificial Chromosome Library  

Microsoft Academic Search

A bacterial artificial chromosome (BAC) library has been constructed for use in bovine genome mapping using the pBeloBAC11 vector. Currently, the library consists of 23,040 clones, which achieves a 70% probability (P= 0.70) of the library containing a specific unique DNA sequence. Sixty thousand clones, or about three haploid bovine genomes, will be required to achieve a 95% probability (P=

LI CAI; J. F. TAYLOR; R. A. WING; D. S. GALLAGHER; S.-S. WOO; S. K. DAVIS

1995-01-01

121

Construction of a Festuca pratensis BAC library for map-based cloning in Festulolium substitution lines  

Microsoft Academic Search

Introgression in Festulolium is a potentially powerful tool to isolate genes for a large number of traits which differ between Festuca pratensis Huds. and Lolium perenne L. Not only are hybrids between the two species fertile, but the two genomes can be distinguished by genomic in situ hybridisation and a high frequency of recombination occurs between homoeologous chromosomes and chromosome

Iain S. Donnison; Donal M. O’Sullivan; Ann Thomas; Peter Canter; Beverley Moore; Ian Armstead; Howard Thomas; Keith J. Edwards; Ian P. King

2005-01-01

122

Counter-selection recombineering of the baculovirus genome: a strategy for seamless modification of repeat-containing BACs.  

PubMed

Recombineering is employed to modify large DNA clones such as fosmids, BACs and PACs. Subtle and seamless modifications can be achieved using counter-selection strategies in which a donor cassette carrying both positive and negative markers inserted in the target clone is replaced by the desired sequence change. We are applying counter-selection recombineering to modify bacmid bMON14272, a recombinant baculoviral genome, as we wish to engineer the virus into a therapeutically useful gene delivery vector with cell targeting characteristics. Initial attempts to replace gp64 with Fusion (F) genes from other baculoviruses resulted in many rearranged clones in which the counter-selection cassette had been deleted. Bacmid bMON14272 contains nine highly homologous regions (hrs) and deletions were mapped to recombination between hr pairs. Recombineering modifications were attempted to decrease intramolecular recombination and/or increase recombineering efficiency. Of these only the use of longer homology arms on the donor molecule proved effective permitting seamless modification. bMON14272, because of the presence of the hr sequences, can be considered equivalent to a highly repetitive BAC and, as such, the optimized method detailed here should prove useful to others applying counter-selection recombineering to modify BACs or PACs containing similar regions of significant repeating homologies. PMID:20621982

Westenberg, Marcel; Soedling, Helen M; Mann, Derek A; Nicholson, Linda J; Dolphin, Colin T

2010-07-09

123

Counter-selection recombineering of the baculovirus genome: a strategy for seamless modification of repeat-containing BACs  

PubMed Central

Recombineering is employed to modify large DNA clones such as fosmids, BACs and PACs. Subtle and seamless modifications can be achieved using counter-selection strategies in which a donor cassette carrying both positive and negative markers inserted in the target clone is replaced by the desired sequence change. We are applying counter-selection recombineering to modify bacmid bMON14272, a recombinant baculoviral genome, as we wish to engineer the virus into a therapeutically useful gene delivery vector with cell targeting characteristics. Initial attempts to replace gp64 with Fusion (F) genes from other baculoviruses resulted in many rearranged clones in which the counter-selection cassette had been deleted. Bacmid bMON14272 contains nine highly homologous regions (hrs) and deletions were mapped to recombination between hr pairs. Recombineering modifications were attempted to decrease intramolecular recombination and/or increase recombineering efficiency. Of these only the use of longer homology arms on the donor molecule proved effective permitting seamless modification. bMON14272, because of the presence of the hr sequences, can be considered equivalent to a highly repetitive BAC and, as such, the optimized method detailed here should prove useful to others applying counter-selection recombineering to modify BACs or PACs containing similar regions of significant repeating homologies.

Westenberg, Marcel; Soedling, Helen M.; Mann, Derek A.; Nicholson, Linda J.; Dolphin, Colin T.

2010-01-01

124

Complete Genome Sequence of a UL96 Mutant Cytomegalovirus Towne-BAC (Bacterial Artificial Chromosome) Isolate Passaged in Fibroblasts To Allow Accumulation of Compensatory Mutations  

PubMed Central

Here, we present the complete genome sequence of a cytomegalovirus Towne-BAC (bacterial artificial chromosome) isolate that we first genetically engineered to mutate the UL96 gene and then serially passaged in human fibroblasts to allow for the accumulation of compensatory mutations. A total of 17 single-base substitutions were discovered in the passaged genome compared to the reference sequence (KF493877).

Brechtel, Teal M.; Tyner, Molly

2013-01-01

125

Relational genome analysis using reference libraries and hybridisation fingerprinting  

Microsoft Academic Search

The genomes of eukaryotic organisms are studied by an integrated approach based on hybridisation techniques. For this purpose, a reference library system has been set up, with a wide range of clone libraries made accessible to probe hybridisation as high density filter grids. Many different library types made from a variety of organisms can thus be analysed in a highly

J HOHEISEL; Mark T. Ross; G ZEHETNER; H LEHRACH

1994-01-01

126

Construction of a BAC Library of the Leymus Cinereus X L. Triticoides Hybrid  

Technology Transfer Automated Retrieval System (TEKTRAN)

Leymus cinereus and L. triticoides are two wildrye grasses with many contrasting morphological and agronomic traits. The interspecific hybrid Leymus cinereus X L. triticoides and its progenies had been used to develop linkage maps of traits and molecular markers. To generate genomic DNA sequence i...

127

Aquaculture Genomics  

Technology Transfer Automated Retrieval System (TEKTRAN)

The genomics chapter covers the basics of genome mapping and sequencing and the current status of several relevant species. The chapter briefly describes the development and use of (cDNA, BAC, etc.) libraries for mapping and obtaining specific sequence information. Other topics include comparative ...

128

The Oryza map alignment project: Construction, alignment and analysis of 12 BAC fingerprint/end sequence framework physical maps that represent the 10 genome types of genus Oryza  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Oryza Map Alignment Project (OMAP) provides the first comprehensive experimental system for understanding the evolution, physiology and biochemistry of a full genus in plants or animals. We have constructed twelve deep-coverage BAC libraries that are representative of both diploid and tetraploid...

129

Construction of a representative genomic library from a hexaploid wheat  

Microsoft Academic Search

The large genome size and the great amount of DNA repeats make it rather diffiult to obtain a representative hexaploid wheat\\u000a genomic library. The protocol is given with modifications to phage isolation and to purification of vector and plant DNAs\\u000a by electrophoresis in low-concentration SeaKem agarose gels. Representative genomic libraries of the soft wheat variety carrying\\u000a a translocated rye chromosome

S. A. Filichkin; A. P. Tikhonov; A. A. Yephremov

1991-01-01

130

FISH mapping of 10 canine BAC clones harbouring genes and microsatellites in the arctic fox and the Chinese raccoon dog genomes.  

PubMed

Cytogenetic mapping of the arctic fox and the Chinese raccoon dog were performed using a set of canine probes derived from the Bacterial Artificial Chromosome (BAC) library. Altogether, 10 BAC clones containing sequences of selected genes (PAX3, HBB, ATP2A2, TECTA, PIT1, ABCA4, ESR2, TPH1, HTR2A, MAOA) and microsatellites were mapped by fluorescence in situ hybridization (FISH) experiments to chromosomes of the canids studied. At present, the cytogenetic map on the arctic fox and Chinese raccoon dog consists of 45 loci each. Chromosomal localization of the BAC clones was in agreement with data obtained by earlier independent comparative chromosome painting. However, two events of telomere-to-centromere inversions were tentatively identified while compared with assignments in the dog karyotype. PMID:16965407

Szczerbal, I; Klukowska-Roetzler, J; Dolf, G; Schelling, C; Switonski, M

2006-10-01

131

Complete Genome Sequence of a Cytomegalovirus Towne-BAC (Bacterial Artificial Chromosome) Isolate Maintained in Escherichia coli for 10 Years and Then Serially Passaged in Human Fibroblasts  

PubMed Central

Here, we present the complete genome sequence of a cytomegalovirus, the Towne-BAC (bacterial artificial chromosome) isolate, which was maintained in bacterial cells for 10 years and then serially passaged in human fibroblasts for 10 passages. A total of 132 nucleotide differences were discovered in the Towne sequence compared to the reference sequence (GenBank accession no. AC146851).

Brechtel, Teal; Tyner, Molly

2013-01-01

132

Complete Genome Sequence of a UL96 Mutant Cytomegalovirus Towne-BAC (Bacterial Artificial Chromosome) Isolate Passaged in Fibroblasts To Allow Accumulation of Compensatory Mutations.  

PubMed

Here, we present the complete genome sequence of a cytomegalovirus Towne-BAC (bacterial artificial chromosome) isolate that we first genetically engineered to mutate the UL96 gene and then serially passaged in human fibroblasts to allow for the accumulation of compensatory mutations. A total of 17 single-base substitutions were discovered in the passaged genome compared to the reference sequence (KF493877). PMID:24158558

Brechtel, Teal M; Tyner, Molly; Tandon, Ritesh

2013-10-24

133

Seamless genome editing in human pluripotent stem cells using custom endonuclease-based gene targeting and the piggyBac transposon.  

PubMed

I report here a detailed protocol for seamless genome editing using the piggyBac transposon in human pluripotent stem cells (hPSCs). Recent advances in custom endonucleases have enabled us to routinely perform genome editing in hPSCs. Conventional approaches use the Cre/loxP system that leaves behind residual sequences in the targeted genome. I used the piggyBac transposon to seamlessly remove a drug selection cassette and demonstrated safe genetic correction of a mutation causing ?-1 antitrypsin deficiency in patient-derived hPSCs. An alternative approach to using the piggyBac transposon to correct mutations involves using single-stranded oligonucleotides, which is a faster process to complete. However, this experimental procedure is rather complicated and it may be hard to achieve homozygous modifications. In contrast, using the piggyBac transposon with drug selection-based enrichment of genetic modifications, as described here, is simple and can yield multiple correctly targeted clones, including homozygotes. Although two rounds of genetic manipulation are required to achieve homozygote modifications, the entire process takes ?3 months to complete. PMID:24071911

Yusa, Kosuke

2013-09-26

134

Re-annotation of the physical map of Glycine max for polyploid-like regions by BAC end sequence driven whole genome shotgun read assembly  

PubMed Central

Background Many of the world's most important food crops have either polyploid genomes or homeologous regions derived from segmental shuffling following polyploid formation. The soybean (Glycine max) genome has been shown to be composed of approximately four thousand short interspersed homeologous regions with 1, 2 or 4 copies per haploid genome by RFLP analysis, microsatellite anchors to BACs and by contigs formed from BAC fingerprints. Despite these similar regions,, the genome has been sequenced by whole genome shotgun sequence (WGS). Here the aim was to use BAC end sequences (BES) derived from three minimum tile paths (MTP) to examine the extent and homogeneity of polyploid-like regions within contigs and the extent of correlation between the polyploid-like regions inferred from fingerprinting and the polyploid-like sequences inferred from WGS matches. Results Results show that when sequence divergence was 1–10%, the copy number of homeologous regions could be identified from sequence variation in WGS reads overlapping BES. Homeolog sequence variants (HSVs) were single nucleotide polymorphisms (SNPs; 89%) and single nucleotide indels (SNIs 10%). Larger indels were rare but present (1%). Simulations that had predicted fingerprints of homeologous regions could be separated when divergence exceeded 2% were shown to be false. We show that a 5–10% sequence divergence is necessary to separate homeologs by fingerprinting. BES compared to WGS traces showed polyploid-like regions with less than 1% sequence divergence exist at 2.3% of the locations assayed. Conclusion The use of HSVs like SNPs and SNIs to characterize BACs wil improve contig building methods. The implications for bioinformatic and functional annotation of polyploid and paleopolyploid genomes show that a combined approach of BAC fingerprint based physical maps, WGS sequence and HSV-based partitioning of BAC clones from homeologous regions to separate contigs will allow reliable de-convolution and positioning of sequence scaffolds (see BES_scaffolds section of SoyGD). This approach will assist genome annotation for paleopolyploid and true polyploid genomes such as soybean and many important cereal and fruit crops.

Saini, Navinder; Shultz, Jeffry; Lightfoot, David A

2008-01-01

135

Construction and characterization of bacterial artificial chromosome library of black-handed spider monkey (Ateles geoffroyi).  

PubMed

The large-insert genomic DNA library is a critical resource for genome-wide genetic dissection of target species. We constructed a high-redundancy bacterial artificial chromosome (BAC) library of a New World monkey species, the black-handed spider monkey (Ateles geoffroyi). A total of 193 152 BAC clones were generated in this library. The average insert size of the BAC clones was estimated to be 184.6 kb with the small inserts (50-100 kb) accounting for less than 3% and the non-recombinant clones only 1.2%. Assuming a similar genome size with humans, the spider monkey BAC library has about 11x genome coverage. In addition, by end sequencing of randomly selected BAC clones, we generated 367 sequence tags for the library. When blasted against human genome, they showed a good correlation between the number of hit clones and the size of the chromosomes, an indication of unbiased chromosomal distribution of the library. This black-handed spider monkey BAC library would serve as a valuable resource in comparative genomic study and large-scale genome sequencing of nonhuman primates. PMID:15060576

Qian, Yaping; Jin, Li; Su, Bing

2004-04-01

136

Chromosomal Mapping of Canine-Derived BAC Clones to the Red Fox and American Mink Genomes  

Microsoft Academic Search

High-quality sequencing of the dog (Canis lupus familiaris) genome has enabled enormous progress in genetic mapping of canine phenotypic variation. The red fox (Vulpes vulpes), another canid species, also exhibits a wide range of variation in coat color, morphology, and behavior. Although the fox genome has not yet been sequenced, canine genomic resources have been used to construct a meiotic

ANNA V. KUKEKOVA; N. V. Vorobieva; V. R. Beklemisheva; J. L. Johnson; S. V. Temnykh; D MITRY V. YUDKIN; L YUDMILA N. TRUT; C. Andre; F. Galibert; G. D. Aguirre; G. M. Acland; A. S. Graphodatsky

2009-01-01

137

Adaptation of a commercial robot for genome library replication  

SciTech Connect

This report describes tools and fixtures developed at the Human Genome Center at Lawrence Berkeley Laboratory for the Hewlett-Packard ORCA{trademark} (Optimized Robot for Chemical Analysis) to replicate large genome libraries. Photographs and engineering drawings of the various custom-designed components are included.

Uber, D.C.; Searles, W.L.

1994-01-01

138

Broad host range vectors for stable genomic library construction.  

PubMed

We describe the construction of 36 stable vectors for genomic library construction in gram-negative species. These vectors contain the pBBR1 replicon that has been shown to stably replicate in every gram-negative species tested. The plasmids also contain bidirectional, rho-independent transcriptional terminators flanking the multiple cloning site, which allows for greater insert stability, and thus, greater genomic representation. Each vector varies in its antibiotic resistance cassette, mobilization function, and promoter used to express insert sequences. These vectors should prove useful in the screening of highly representational genomic libraries in a broad variety of gram-negative species. PMID:16496398

Lynch, Michael D; Gill, Ryan T

2006-05-01

139

BAC-HAPPY Mapping (BAP Mapping): A New and Efficient Protocol for Physical Mapping  

PubMed Central

Physical and linkage mapping underpin efforts to sequence and characterize the genomes of eukaryotic organisms by providing a skeleton framework for whole genome assembly. Hitherto, linkage and physical “contig” maps were generated independently prior to merging. Here, we develop a new and easy method, BAC HAPPY MAPPING (BAP mapping), that utilizes BAC library pools as a HAPPY mapping panel together with an Mbp-sized DNA panel to integrate the linkage and physical mapping efforts into one pipeline. Using Arabidopsis thaliana as an exemplar, a set of 40 Sequence Tagged Site (STS) markers spanning ?10% of chromosome 4 were simultaneously assembled onto a BAP map compiled using both a series of BAC pools each comprising 0.7x genome coverage and dilute (0.7x genome) samples of sheared genomic DNA. The resultant BAP map overcomes the need for polymorphic loci to separate genetic loci by recombination and allows physical mapping in segments of suppressed recombination that are difficult to analyze using traditional mapping techniques. Even virtual “BAC-HAPPY-mapping” to convert BAC landing data into BAC linkage contigs is possible.

Vu, Giang T. H.; Dear, Paul H.; Caligari, Peter D. S.; Wilkinson, Mike J.

2010-01-01

140

Genome-Scale Validation of Deep-Sequencing Libraries  

Microsoft Academic Search

Chromatin immunoprecipitation followed by high-throughput (HTP) sequencing (ChIP-seq) is a powerful tool to establish protein-DNA interactions genome-wide. The primary limitation of its broad application at present is the often-limited access to sequencers. Here we report a protocol, Mab-seq, that generates genome-scale quality evaluations for nucleic acid libraries intended for deep-sequencing. We show how commercially available genomic microarrays can be used

Dominic Schmidt; Rory Stark; Michael D. Wilson; Gordon D. Brown; Duncan T. Odom; Jürg Bähler

2008-01-01

141

Genomic Sequence around Butterfly Wing Development Genes: Annotation and Comparative Analysis  

Microsoft Academic Search

BackgroundAnalysis of genomic sequence allows characterization of genome content and organization, and access beyond gene-coding regions for identification of functional elements. BAC libraries, where relatively large genomic regions are made readily available, are especially useful for species without a fully sequenced genome and can increase genomic coverage of phylogenetic and biological diversity. For example, no butterfly genome is yet available

Inęs C. Conceiçăo; Anthony D. Long; Jonathan D. Gruber; Patrícia Beldade

2011-01-01

142

Chemical Biology\\/ Chemical Genetics\\/ Chemical Genomics: Importance of Chemical Library  

Microsoft Academic Search

A new field of science, chemical biology\\/ chemical genetics\\/ chemical genomics (cb\\/cg\\/cg) has emerged since the late 1990's, especially in the United States. The NIH Roadmap agenda, Molecular Libraries Screening Center Network (MLSCN), became a drive force to push cb\\/cg\\/cg forward. Cb\\/cg\\/cg studies consist of three methodologies, chemical libraries with small molecules, high-throughput screenings, and computational databases. In this review,

Fumihiko Kugawa; Masaru Watanabe; Fuyuhiko Tamanoi

2007-01-01

143

Novel Bacterial Artificial Chromosome Vector pUvBBAC for Use in Studies of the Functional Genomics of Listeria spp  

Microsoft Academic Search

Bacterial artificial chromosome (BAC) vectors are important tools for microbial genome research. We con- structed a novel BAC vector, pUvBBAC, for replication in both gram-negative and gram-positive bacterial hosts. The pUvBBAC vector was used to generate a BAC library for the facultative intracellular pathogen Listeria monocytogenes EGD-e. The library had insert sizes ranging from 68 to 178 kb. We identified

Torsten Hain; Sonja Otten; U. von Both; S. S. Chatterjee; U. Technow; A. Billion; R. Ghai; W. Mohamed; E. Domann; T. Chakraborty

2008-01-01

144

Genome-wide target profiling of piggyBac and Tol2 in HEK 293: pros and cons for gene discovery and gene therapy  

Microsoft Academic Search

Background  DNA transposons have emerged as indispensible tools for manipulating vertebrate genomes with applications ranging from insertional\\u000a mutagenesis and transgenesis to gene therapy. To fully explore the potential of two highly active DNA transposons, piggyBac and Tol2, as mammalian genetic tools, we have conducted a side-by-side comparison of the two transposon systems in the same setting\\u000a to evaluate their advantages and

Yaa-Jyuhn J Meir; Matthew T Weirauch; Herng-Shing Yang; Pei-Cheng Chung; Robert K Yu; Sareina C-Y Wu

2011-01-01

145

Development and analysis of a germline BAC resource for the sea lamprey, a vertebrate that undergoes substantial chromatin diminution.  

PubMed

Over the last several years, the sea lamprey (Petromyzon marinus) has grown substantially as a model for understanding the evolutionary fundaments and capacity of vertebrate developmental and genome biology. Recent work on the lamprey genome has resulted in a preliminary assembly of the lamprey genome and led to the realization that nearly all somatic cell lineages undergo extensive programmed rearrangements. Here we describe the development of a bacterial artificial chromosome (BAC) resource for lamprey germline DNA and use sequence information from this resource to probe the subchromosomal structure of the lamprey genome. The arrayed germline BAC library represents approximately 10x coverage of the lamprey genome. Analyses of BAC-end sequences reveal that the lamprey genome possesses a high content of repetitive sequences (relative to human), which show strong clustering at the subchromosomal level. This pattern is not unexpected given that the sea lamprey genome is dispersed across a large number of chromosomes (n approximately 99) and suggests a low-copy DNA targeting strategy for efficiently generating informative paired-BAC-end linkages from highly repetitive genomes. This library therefore represents a new and biologically informed resource for understanding the structure of the lamprey genome and the biology of programmed genome rearrangement. PMID:20195622

Smith, Jeramiah J; Stuart, Andrew B; Sauka-Spengler, Tatjana; Clifton, Sandra W; Amemiya, Chris T

2010-03-02

146

A first generation BAC-based physical map of the rainbow trout genome  

Microsoft Academic Search

BACKGROUND: Rainbow trout (Oncorhynchus mykiss) are the most-widely cultivated cold freshwater fish in the world and an important model species for many research areas. Coupling great interest in this species as a research model with the need for genetic improvement of aquaculture production efficiency traits justifies the continued development of genomics research resources. Many quantitative trait loci (QTL) have been

Yniv Palti; Ming-Cheng Luo; Yuqin Hu; Carine Genet; Frank M You; Roger L Vallejo; Gary H Thorgaard; Paul A Wheeler; Caird E Rexroad

2009-01-01

147

Distribution of genes and repetitive elements in the Diabrotica virgifera virgifera genome estimated using BAC sequencing  

Technology Transfer Automated Retrieval System (TEKTRAN)

Feeding damage caused by the corn rootworm, Diabrotica virgifera virgifera, is destructive to corn plants in North America and Europe where control remains challenging due to evolution of resistance traits that allow survival when exposed to chemical and transgenic toxins. Genome sequencing of an i...

148

The complexity of Rhipicephalus (Boophilus) microplus genome characterised through detailed analysis of two BAC clones  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background: Rhipicephalus (Boophilus) microplus (Rmi) a major cattle ectoparasite and tick borne disease vector, impacts on animal welfare and industry productivity. In arthropod research there is an absence of a complete Chelicerate genome, which includes ticks, mites, spiders, scorpions and crusta...

149

BAC TransgeneOmics  

PubMed Central

The interpretation of genome sequences requires reliable and standardized methods to assess protein function at high throughput. Here we describe a fast and reliable pipeline to study protein function in mammalian cells based on protein tagging in bacterial artificial chromosomes (BACs). The large size of the BAC transgenes ensures the presence of most, if not all, regulatory elements and results in expression that closely matches that of the endogenous gene. We show that BAC transgenes can be rapidly and reliably generated using 96-well-format recombineering. After stable transfection of these transgenes into human tissue culture cells or mouse embryonic stem cells, the localization, protein-protein and/or protein-DNA interactions of the tagged protein are studied using generic, tag-based assays. The same high-throughput approach will be generally applicable to other model systems.

Poser, Ina; Sarov, Mihail; Hutchins, James R A; Heriche, Jean-Karim; Toyoda, Yusuke; Pozniakovsky, Andrei; Weigl, Daniela; Nitzsche, Anja; Hegemann, Bjorn; Bird, Alexander W; Pelletier, Laurence; Kittler, Ralf; Hua, Sujun; Naumann, Ronald; Augsburg, Martina; Sykora, Martina M; Hofemeister, Helmut; Zhang, Youming; Nasmyth, Kim; White, Kevin P; Dietzel, Steffen; Mechtler, Karl; Durbin, Richard; Stewart, A Francis; Peters, Jan-Michael; Buchholz, Frank; Hyman, Anthony A

2009-01-01

150

Serial assembly of Thermus megaplasmid DNA in the genome of Bacillus subtilis 168: a BAC-based domino method applied to DNA with a high GC content.  

PubMed

Bacillus subtilis is the only bacterium-based host able to clone giant DNA above 1000 kbp. DNA previously handled by this host was limited to that with GC content similar to or lower than that of the B. subtilis genome. To expand the target DNA range to higher GC content, we tried to clone a pTT27 megaplasmid (257 kbp, 69% of G+C) from Thermus thermophilus. To facilitate the reconstruction process, we subcloned pTT27 in a bacterial artificial chromosome (BAC) vector of Escherichia coli. Owing to the ability of BAC to carry around 100 kbp DNA, only 4 clones were needed to cover the pTT27 and conduct step-by-step assembly in the B. subtilis genome. The full length of 257 kbp was reconstructed through 3 intermediary lengths (108, 153, and 226 kbp), despite an unexpected difficulty in the maintenance of DNA >200 kbp. Retrieval of these four pTT27 segments from the B. subtilis genome by genetic transfer to a plasmid pLS20 was attempted. A stable plasmid clone was obtained only for the 108 and 153 kbp intermediates. The B. subtilis genome was demonstrated to accommodate large DNA with a high GC content, but may be restricted to less than 200 kbp by unidentified mechanisms. PMID:22553167

Ohtani, Naoto; Hasegawa, Miki; Sato, Mitsuru; Tomita, Masaru; Kaneko, Shinya; Itaya, Mitsuhiro

2012-05-16

151

A BAC-Based Physical Map of Zhikong Scallop (Chlamys farreri Jones et Preston)  

PubMed Central

Zhikong scallop (Chlamys farreri) is one of the most economically important aquaculture species in China. Physical maps are crucial tools for genome sequencing, gene mapping and cloning, genetic improvement and selective breeding. In this study, we have developed a genome-wide, BAC-based physical map for the species. A total of 81,408 clones from two BAC libraries of the scallop were fingerprinted using an ABI 3130xl Genetic Analyzer and a fingerprinting kit developed in our laboratory. After data processing, 63,641 (?5.8× genome coverage) fingerprints were validated and used in the physical map assembly. A total of 3,696 contigs were assembled for the physical map. Each contig contained an average of 10.0 clones, with an average physical size of 490 kb. The combined total physical size of all contigs was 1.81 Gb, equivalent to approximately 1.5 fold of the scallop haploid genome. A total of 10,587 BAC end sequences (BESs) and 167 markers were integrated into the physical map. We evaluated the physical map by overgo hybridization, BAC-FISH (fluorescence in situ hybridization), contig BAC pool screening and source BAC library screening. The results have provided evidence of the high reliability of the contig physical map. This is the first physical map in mollusc; therefore, it provides an important platform for advanced research of genomics and genetics, and mapping of genes and QTL of economical importance, thus facilitating the genetic improvement and selective breeding of the scallop and other marine molluscs.

Zhang, Xiaojun; Zhao, Cui; Huang, Chao; Duan, Hu; Huan, Pin; Liu, Chengzhang; Zhang, Xiuying; Zhang, Yang; Li, Fuhua; Zhang, Hong-Bin; Xiang, Jianhai

2011-01-01

152

The Atlas Genome Assembly System  

PubMed Central

Atlas is a suite of programs developed for assembly of genomes by a “combined approach” that uses DNA sequence reads from both BACs and whole-genome shotgun (WGS) libraries. The BAC clones afford advantages of localized assembly with reduced computational load, and provide a robust method for dealing with repeated sequences. Inclusion of WGS sequences facilitates use of different clone insert sizes and reduces data production costs. A core function of Atlas software is recruitment of WGS sequences into appropriate BACs based on sequence overlaps. Because construction of consensus sequences is from local assembly of these reads, only small (<0.1%) units of the genome are assembled at a time. Once assembled, each BAC is used to derive a genomic layout. This “sequence-based” growth of the genome map has greater precision than with non-sequence-based methods. Use of BACs allows correction of artifacts due to repeats at each stage of the process. This is aided by ancillary data such as BAC fingerprint, other genomic maps, and syntenic relations with other genomes. Atlas was used to assemble a draft DNA sequence of the rat genome; its major components including overlapper and split-scaffold are also being used in pure WGS projects.

Havlak, Paul; Chen, Rui; Durbin, K. James; Egan, Amy; Ren, Yanru; Song, Xing-Zhi; Weinstock, George M.; Gibbs, Richard A.

2004-01-01

153

PCR identification of durum wheat BAC clones containing genes coding for carotenoid biosynthesis enzymes and their chromosome localization.  

PubMed

Carotenoids are essential components in all plants. Their accumulation in wheat seed determines the endosperm colour, which is an important quality trait in wheat. In this study, we report the isolation of BAC clones containing genes coding for three different enzymes of the carotenoid biosynthesis pathway: phytoene synthase (PSY), phytoene desaturase (PDS), and zeta-carotene desaturase (ZDS). Primers were designed on the basis of wheat ESTs similar to the sequences of these three genes in other species, and used to screen a BAC library from Triticum turgidum var. durum (2n = 28, genomes AABB). Eight, six, and nine 384-well plates containing at least one positive clone were found for PSY, PDS, and ZDS, respectively. BACs selected for each of these genes were then divided in two groups corresponding to the A and B genomes of tetraploid wheat, based on differences in the length of the PCR amplification products, conformation-sensitive gel electrophoresis (CSGE), or cleavage amplification polymorphisms. Positive clones were then assigned to chromosomes using a set of D genome substitution lines in T. turgidum var. durum 'Langdon'. PSY clones were localized on chromosomes 5A and 5B, PDS on chromosomes 4A and 4B, and ZDS on chromosomes 2A and 2B. The strategies used for the PCR screening of large BAC libraries and for the differentiation of BAC clones from different genomes in a polyploid species are discussed. PMID:15499405

Cenci, A; Somma, S; Chantret, N; Dubcovsky, J; Blanco, A

2004-10-01

154

Terminal region proximal internal domain sequences of the piggyBac transposon are necessary for efficient transformation of target genomes  

Technology Transfer Automated Retrieval System (TEKTRAN)

A previous report demonstrated that deletion mutations of the entire piggyBac internal domain had no effect on interplasmid transposition in microinjected embryos. In applying internal domain deleted vectors to transformations of insects we noted a significant decline in the efficiency of transforma...

155

A bacterial artificial chromosome (BAC) library of sugar beet and a physical map of the region encompassing the bolting gene B  

Microsoft Academic Search

In sugar beet ( Beta vulgaris L.), early bolting is caused by a single dominant gene, designated B. Twenty AFLP markers selected from a 7.8-cM segment of the B region on chromosome 2 were used to screen a YAC library, and a first-generation physical map including the B gene, made up of 11 YACs, was established. Because the genome coverage

U. Hohmann; G. Jacobs; A. Telgmann; R. M. Gaafar; S. Alam; C. Jung

2003-01-01

156

Bacterial artificial chromosome-based physical map of the rice genome constructed by restriction fingerprint analysis.  

PubMed Central

Genome-wide physical mapping with bacteria-based large-insert clones (e.g., BACs, PACs, and PBCs) promises to revolutionize genomics of large, complex genomes. To accelerate rice and other grass species genome research, we developed a genome-wide BAC-based map of the rice genome. The map consists of 298 BAC contigs and covers 419 Mb of the 430-Mb rice genome. Subsequent analysis indicated that the contigs constituting the map are accurate and reliable. Particularly important to proficiency were (1) a high-resolution, high-throughput DNA sequencing gel-based electrophoretic method for BAC fingerprinting, (2) the use of several complementary large-insert BAC libraries, and (3) computer-aided contig assembly. It has been demonstrated that the fingerprinting method is not significantly influenced by repeated sequences, genome size, and genome complexity. Use of several complementary libraries developed with different restriction enzymes minimized the "gaps" in the physical map. In contrast to previous estimates, a clonal coverage of 6.0-8.0 genome equivalents seems to be sufficient for development of a genome-wide physical map of approximately 95% genome coverage. This study indicates that genome-wide BAC-based physical maps can be developed quickly and economically for a variety of plant and animal species by restriction fingerprint analysis via DNA sequencing gel-based electrophoresis.

Tao, Q; Chang, Y L; Wang, J; Chen, H; Islam-Faridi, M N; Scheuring, C; Wang, B; Stelly, D M; Zhang, H B

2001-01-01

157

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

PubMed Central

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.

2010-01-01

158

Theobroma cacao: A genetically integrated physical map and genome-scale comparative synteny analysis  

Technology Transfer Automated Retrieval System (TEKTRAN)

A comprehensive integrated genomic framework is considered a centerpiece of genomic research. In collaboration with the USDA-ARS (SHRS) and Mars Inc., the Clemson University Genomics Institute (CUGI) has developed a genetically anchored physical map of the T. cacao genome. Three BAC libraries contai...

159

Chromosome region-specific libraries for human genome analysis  

SciTech Connect

We have made important progress since the beginning of the current grant year. We have further developed the microdissection and PCR- assisted microcloning techniques using the linker-adaptor method. We have critically evaluated the microdissection libraries constructed by this microtechnology and proved that they are of high quality. We further demonstrated that these microdissection clones are useful in identifying corresponding YAC clones for a thousand-fold expansion of the genomic coverage and for contig construction. We are also improving the technique of cloning the dissected fragments in test tube by the TDT method. We are applying both of these PCR cloning technique to human chromosomes 2 and 5 to construct region-specific libraries for physical mapping purposes of LLNL and LANL. Finally, we are exploring efficient procedures to use unique sequence microclones to isolate cDNA clones from defined chromosomal regions as valuable resources for identifying expressed gene sequences in the human genome. We believe that we are making important progress under the auspices of this DOE human genome program grant and we will continue to make significant contributions in the coming year. 4 refs., 4 figs.

Kao, Fa-Ten.

1991-01-01

160

Three minimum tile paths from bacterial artificial chromosome libraries of the soybean (Glycine max cv. 'Forrest'): tools for structural and functional genomics  

PubMed Central

Background The creation of minimally redundant tile paths (hereafter MTP) from contiguous sets of overlapping clones (hereafter contigs) in physical maps is a critical step for structural and functional genomics. Build 4 of the physical map of soybean (Glycine max L. Merr. cv. 'Forrest') showed the 1 Gbp haploid genome was composed of 0.7 Gbp diploid, 0.1 Gbp tetraploid and 0.2 Gbp octoploid regions. Therefore, the size of the unique genome was about 0.8 Gbp. The aim here was to create MTP sub-libraries from the soybean cv. Forrest physical map builds 2 to 4. Results The first MTP, named MTP2, was 14,208 clones (of mean insert size 140 kbp) picked from the 5,597 contigs of build 2. MTP2 was constructed from three BAC libraries (BamHI (B), HindIII (H) and EcoRI (E) inserts). MTP2 encompassed the contigs of build 3 that derived from build 2 by a series of contig merges. MTP2 encompassed 2 Gbp compared to the soybean haploid genome of 1 Gbp and does not distinguish regions by ploidy. The second and third MTPs, called MTP4BH and MTP4E, were each based on build 4. Each was semi-automatically selected from 2,854 contigs. MTP4BH was 4,608 B and H insert clones of mean size 173 kbp in the large (27.6 kbp) T-DNA vector pCLD04541. MTP4BH was suitable for plant transformation and functional genomics. MTP4E was 4,608 BAC clones with large inserts (mean 175 kbp) in the small (7.5 kbp) pECBAC1 vector. MTP4E was suitable for DNA sequencing. MTP4BH and MTP4E clones each encompassed about 0.8 Gbp, the 0.7 Gbp diploid regions and 0.05 Gbp each from the tetraploid and octoploid regions. MTP2 and MTP4BH were used for BAC-end sequencing, EST integration, micro-satellite integration into the physical map and high information content fingerprinting. MTP4E will be used for genome sequence by pooled genomic clone index. Conclusion Each MTP and associated BES will be useful to deconvolute and ultimately finish the whole genome shotgun sequence of soybean.

Shultz, JL; Yesudas, C; Yaegashi, S; Afzal, AJ; Kazi, S; Lightfoot, DA

2006-01-01

161

Genomic analysis of Ovis aries ( Ovar ) MHC class IIa loci  

Microsoft Academic Search

Determining the genomic organization of the Ovis aries (Ovar) major histocompatibility complex class IIa region is essential for future functional studies related to antigen presentation.\\u000a In this study, a bacterial artificial chromosome (BAC) library of genomic DNA from peripheral blood leukocytes (PBL) of a\\u000a Rambouillet ram was constructed, and BAC clone consisting of the major histocompatibility complex (MHC) class II

Lynn M. Herrmann-Hoesing; Stephen N. White; Lowell S. Kappmeyer; David R. Herndon; Donald P. Knowles

2008-01-01

162

A physical map of the bovine genome  

Microsoft Academic Search

BACKGROUND: Cattle are important agriculturally and relevant as a model organism. Previously described genetic and radiation hybrid (RH) maps of the bovine genome have been used to identify genomic regions and genes affecting specific traits. Application of these maps to identify influential genetic polymorphisms will be enhanced by integration with each other and with bacterial artificial chromosome (BAC) libraries. The

Warren M Snelling; Readman Chiu; Jacqueline E Schein; Matthew Hobbs; Colette a Abbey; David L Adelson; Jan Aerts; Gary L Bennett; Ian E Bosdet; Mekki Boussaha; Rudiger Brauning; Alexandre R Caetano; Marcos M Costa; Allan M Crawford; Brian P Dalrymple; Andr'e Eggen; Annelie Everts-van der Wind; Sandrine Floriot; Mathieu Gautier; Clare a Gill; Ronnie D Green; Robert Holt; Oliver Jann; Steven Jm Jones; Steven M Kappes; John W Keele; Pieter J de Jong; Denis M Larkin; Harris a Lewin; John C McEwan; Stephanie McKay; Marco a Marra; Carrie a Mathewson; Lakshmi K Matukumalli; Stephen S Moore; Brenda Murdoch; Frank W Nicholas; Kazutoyo Osoegawa; Alice Roy; Hanni Salih; Laurent Schibler; Robert D Schnabel; Licia Silveri; Loren C Skow; Timothy Pl Smith; Tad S Sonstegard; Jeremy F Taylor; Ross Tellam; Curtis P Van Tassell; John L Williams; James E Womack; Natasja H Wye; George Yang; Shaying Zhao

2007-01-01

163

GenomeTools: A Comprehensive Software Library for Efficient Processing of Structured Genome Annotations.  

PubMed

Genome annotations are often published as plain text files describing genomic features and their subcomponents by an implicit annotation graph. In this paper, we present the GenomeTools, a convenient and efficient software library and associated software tools for developing bioinformatics software intended to create, process or convert annotation graphs. The GenomeTools strictly follow the annotation graph approach, offering a unified graph-based representation. This gives the developer intuitive and immediate access to genomic features and tools for their manipulation. To process large annotation sets with low memory overhead, we have designed and implemented an efficient pull-based approach for sequential processing of annotations. This allows to handle even the largest annotation sets, such as a complete catalogue of human variations. Our object-oriented C-based software library enables a developer to conveniently implement their own functionality on annotation graphs and to integrate it into larger workflows, simultaneously accessing compressed sequence data if required. The careful C implementation of the GenomeTools does not only ensure a light-weight memory footprint while allowing full sequential as well as random access to the annotation graph, but also facilitates the creation of bindings to a variety of script programming languages (like Python and Ruby) sharing the same interface. PMID:24091398

Gremme, Gordon; Steinbiss, Sascha; Kurtz, Stefan

164

Transposon-mediated BAC transgenesis in zebrafish and mice  

PubMed Central

Background Bacterial artificial chromosomes (BACs) are among the most widely used tools for studies of gene regulation and function in model vertebrates, yet methods for predictable delivery of BAC transgenes to the genome are currently limited. This is because BAC transgenes are usually microinjected as naked DNA into fertilized eggs and are known to integrate as multi-copy concatamers in the genome. Although conventional methods for BAC transgenesis have been very fruitful, complementary methods for generating single copy BAC integrations would be desirable for many applications. Results We took advantage of the precise cut-and-paste behavior of a natural transposon, Tol2, to develop a new method for BAC transgenesis. In this new method, the minimal sequences of the Tol2 transposon were used to deliver precisely single copies of a ~70 kb BAC transgene to the zebrafish and mouse genomes. We mapped the BAC insertion sites in the genome by standard PCR methods and confirmed transposase-mediated integrations. Conclusion The Tol2 transposon has a surprisingly large cargo capacity that can be harnessed for BAC transgenesis. The precise delivery of single-copy BAC transgenes by Tol2 represents a useful complement to conventional BAC transgenesis, and could aid greatly in the production of transgenic fish and mice for genomics projects, especially those in which single-copy integrations are desired.

Suster, Maximiliano L; Sumiyama, Kenta; Kawakami, Koichi

2009-01-01

165

A First Generation BAC-Based Physical Map of the Asian Seabass (Lates calcarifer)  

PubMed Central

Background The Asian seabass (Lates calcarifer) is an important marine foodfish species in Southeast Asia and Australia. Genetic improvement of this species has been achieved to some extent through selective breeding programs since 1990s. Several genomic tools such as DNA markers, a linkage map, cDNA and BAC libraries have been developed to assist selective breeding. A physical map is still lacking, although it is essential for positional cloning of genes located in quantitative trait loci (QTL) and assembly of whole genome sequences. Methodology/Principal Findings A genome-wide physical map of the Asian seabass was constructed by restriction fingerprinting of 38,208 BAC clones with SNaPshot HICF FPC technique. A total of 30,454 were assembled into 2,865 contigs. The physical length of the assembled contigs summed up to 665 Mb. Analyses of some contigs using different methods demonstrated the reliability of the assembly. Conclusions/Significance The present physical map is the first physical map for Asian seabass. This physical map will facilitate the fine mapping of QTL for economically important traits and the positional cloning of genes located in QTL. It will also be useful for the whole genome sequencing and assembly. Detailed information about BAC-contigs and BAC clones are available upon request.

Xia, Jun Hong; Feng, Felicia; Lin, Grace; Wang, Chun Ming; Yue, Gen Hua

2010-01-01

166

Human Cytomegalovirus: Bacterial Artificial Chromosome (BAC) Cloning and Genetic Manipulation  

PubMed Central

Our understanding of human cytomegalovirus (HCMV) biology was long hindered by the inability to perform efficient viral genetic analysis. This hurdle was recently overcome when the genomes of multiple HCMV strains were cloned as infectious bacterial artificial chromosomes (BACs). The BAC system takes advantage of the single-copy F plasmid of E. coli that can stably carry large pieces of foreign DNA. In this system, a recombinant HCMV virus carrying a modified F plasmid is first generated in eukaryotic cells. Recombinant viral genomes are then isolated and recovered in E. coli as BAC clones. BAC-captured viral genomes can be manipulated using prokaryotic genetics, and recombinant virus can be reconstituted from BAC transfection in eukaryotic cells. The BAC reverse genetic system provides a reliable and efficient method to introduce genetic alterations into the viral genome in E.coli and subsequently analyze their effects on virus biology in eukaryotic cells.

Paredes, Anne M.; Yu, Dong

2011-01-01

167

Alignment of the Genomes of Brachypodium distachyon and Temperate Cereals and Grasses Using Bacterial Artificial Chromosome Landing With Fluorescence in Situ Hybridization  

Microsoft Academic Search

As part of an initiative to develop Brachypodium distachyon as a genomic ''bridge'' species between rice and the temperate cereals and grasses, a BAC library has been constructed for the two diploid (2n Ľ 2x Ľ 10) genotypes, ABR1 and ABR5. The library consists of 9100 clones, with an approximate average insert size of 88 kb, representing 2.22 genome equivalents.

Robert Hasterok; Agnieszka Marasek; Iain S. Donnison; Ian Armstead; Ann Thomas; Ian P. King; Elzbieta Wolny; Dominika Idziak; John Draper; Glyn Jenkins

2006-01-01

168

Herpesvirus BACs: Past, Present, and Future  

PubMed Central

The herpesviridae are a large family of DNA viruses with large and complicated genomes. Genetic manipulation and the generation of recombinant viruses have been extremely difficult. However, herpesvirus bacterial artificial chromosomes (BACs) that were developed approximately 10 years ago have become useful and powerful genetic tools for generating recombinant viruses to study the biology and pathogenesis of herpesviruses. For example, BAC-directed deletion mutants are commonly used to determine the function and essentiality of viral genes. In this paper, we discuss the creation of herpesvirus BACs, functional analyses of herpesvirus mutants, and future applications for studies of herpesviruses. We describe commonly used methods to create and mutate herpesvirus BACs (such as site-directed mutagenesis and transposon mutagenesis). We also evaluate the potential future uses of viral BACs, including vaccine development and gene therapy.

Warden, Charles; Tang, Qiyi; Zhu, Hua

2011-01-01

169

Towards genetic genome projects: genomic library screening and gene-targeting vector construction in a single step  

Microsoft Academic Search

We have developed technologies that simplify genomic library construction and screening, substantially reducing both the time and the cost associated with traditional library screening methods and facilitating the generation of gene-targeting constructs. By taking advantage of homologous recombination in Escherichia coli, we were able to use as little as 80 bp of total sequence homology to screen for a specific

Pumin Zhang; Mamei Z. Li; Stephen J. Elledge

2001-01-01

170

INTEGRATED GENETIC, PHYSICAL, AND COMPARATIVE MAPPING OF THE COTTON GENOME  

Technology Transfer Automated Retrieval System (TEKTRAN)

Integrated genetic, physical, and comparative maps of the cotton genome are important to cotton functional genomics and other advanced biological studies. We are using the BAC libraries, developed from an Upland cotton genetic standard TM-1, to construct physical contigs and isolate SSR markers tha...

171

Sequencing, annotation and comparative analysis of nine BACs of giant panda (Ailuropoda melanoleuca).  

PubMed

A 10-fold BAC library for giant panda was constructed and nine BACs were selected to generate finish sequences. These BACs could be used as a validation resource for the de novo assembly accuracy of the whole genome shotgun sequencing reads of giant panda newly generated by the Illumina GA sequencing technology. Complete sanger sequencing, assembly, annotation and comparative analysis were carried out on the selected BACs of a joint length 878 kb. Homologue search and de novo prediction methods were used to annotate genes and repeats. Twelve protein coding genes were predicted, seven of which could be functionally annotated. The seven genes have an average gene size of about 41 kb, an average coding size of about 1.2 kb and an average exon number of 6 per gene. Besides, seven tRNA genes were found. About 27 percent of the BAC sequence is composed of repeats. A phylogenetic tree was constructed using neighbor-join algorithm across five species, including giant panda, human, dog, cat and mouse, which reconfirms dog as the most related species to giant panda. Our results provide detailed sequence and structure information for new genes and repeats of giant panda, which will be helpful for further studies on the giant panda. PMID:20596962

Zheng, Yang; Cai, Jing; Li, JianWen; Li, Bo; Lin, RunMao; Tian, Feng; Wang, XiaoLing; Wang, Jun

2010-02-12

172

Integration of physical and genetic maps of common bean through BAC-derived microsatellite markers  

PubMed Central

Background Common bean (Phaseolus vulgaris L.) is the most important legume for direct human consumption and the goal of this study was to integrate a recently constructed physical map for the species with a microsatellite based genetic map using a BAC library from the genotype G19833 and the recombinant inbred line population DOR364 × G19833. Results We searched for simple sequence repeats (SSRs) in the 89,017 BAC-end sequences (BES) from the physical map and genetically mapped any polymorphic BES-SSRs onto the genetic map. Among the BES it was possible to identify 623 contig-linked SSRs, most of which were highly AT-rich. A subgroup of 230 di-nucleotide and tri-nucleotide based SSR primer pairs from these BACs was tested on the mapping parents with 176 single copy loci and 114 found to be polymorphic markers. Of these, 99 were successfully integrated into the genetic map. The 99 linkages between the genetic and physical maps corresponded to an equal number of contigs containing a total of 5,055 BAC clones. Conclusions Class II microsatellites were more common in the BES than longer class I microsatellites. Both types of markers proved to be valuable for linking BAC clones to the genetic map and were successfully placed across all 11 linkage groups. The integration of common bean physical and genetic maps is an important part of comparative genome analysis and a prelude to positional cloning of agronomically important genes for this crop.

2010-01-01

173

Gene Transfer Efficiency and Genome-Wide Integration Profiling of Sleeping Beauty, Tol2, and PiggyBac Transposons in Human Primary T Cells  

PubMed Central

In this study, we compared the genomic integration efficiencies and transposition site preferences of Sleeping Beauty (SB or SB11), Tol2, and piggyBac (PB) transposon systems in primary T cells derived from peripheral blood lymphocytes (PBL) and umbilical cord blood (UCB). We found that PB demonstrated the highest efficiency of stable gene transfer in PBL-derived T cells, whereas SB11 and Tol2 mediated intermediate and lowest efficiencies, respectively. Southern hybridization analysis demonstrated that PB generated the highest number of integrants when compared to SB and Tol2 in both PBL and UCB T cells. Tol2 and PB appeared more likely to promote clonal expansion than SB, which may be in part due to the dysregulated expression of cancer-related genes near the insertion sites. Genome-wide integration analysis demonstrated that SB, Tol2, and PB integrations occurred in all the chromosomes without preference. Additionally, Tol2 and PB integration sites were mainly localized near transcriptional start sites (TSSs), CpG islands and DNaseI hypersensitive sites, whereas SB integrations were randomly distributed. These results suggest that SB may be a preferential choice of the delivery vector in T cells due to its random integration site preference and relatively high efficiency, and support continuing development of SB-mediated T-cell phase I trials.

Huang, Xin; Guo, Hongfeng; Tammana, Syam; Jung, Yong-Chul; Mellgren, Emil; Bassi, Preetinder; Cao, Qing; Tu, Zheng Jin; Kim, Yeong C; Ekker, Stephen C; Wu, Xiaolin; Wang, San Ming; Zhou, Xianzheng

2010-01-01

174

Bacterial Artificial Chromosome Libraries of Pulse Crops: Characteristics and Applications  

PubMed Central

Pulse crops are considered minor on a global scale despite their nutritional value for human consumption. Therefore, they are relatively less extensively studied in comparison with the major crops. The need to improve pulse crop production and quality will increase with the increasing global demand for food security and people's awareness of nutritious food. The improvement of pulse crops will require fully utilizing all their genetic resources. Bacterial artificial chromosome (BAC) libraries of pulse crops are essential genomic resources that have the potential to accelerate gene discovery and enhance molecular breeding in these crops. Here, we review the availability, characteristics, applications, and potential applications of the BAC libraries of pulse crops.

Yu, Kangfu

2012-01-01

175

Integrase-directed recovery of functional genes from genomic libraries  

PubMed Central

Large population sizes, rapid growth and 3.8 billion years of evolution firmly establish microorganisms as a major source of the planet's biological and genetic diversity. However, up to 99% of the microorganisms in a given environment cannot be cultured. Culture-independent methods that directly access the genetic potential of an environmental sample can unveil new proteins with diverse functions, but the sequencing of random DNA can generate enormous amounts of extraneous data. Integrons are recombination systems that accumulate open reading frames (gene cassettes), many of which code for functional proteins with enormous adaptive potential. Some integrons harbor hundreds of gene cassettes and evidence suggests that the gene cassette pool may be limitless in size. Accessing this genetic pool has been hampered since sequence-based techniques, such as hybridization or PCR, often recover only partial genes or a small subset of those present in the sample. Here, a three-plasmid genetic strategy for the sequence-independent recovery of gene cassettes from genomic libraries is described and its use by retrieving functional gene cassettes from the chromosomal integron of Vibrio vulnificus ATCC 27562 is demonstrated. By manipulating the natural activity of integrons, we can gain access to the caches of functional genes amassed by these structures.

Rowe-Magnus, Dean A.

2009-01-01

176

Development of the piggyBac transposable system for Plasmodium berghei and its application for random mutagenesis in malaria parasites  

PubMed Central

Background The genome of a number of species of malaria parasites (Plasmodium spp.) has been sequenced in the hope of identifying new drug and vaccine targets. However, almost one-half of predicted Plasmodium genes are annotated as hypothetical and are difficult to analyse in bulk due to the inefficiency of current reverse genetic methodologies for Plasmodium. Recently, it has been shown that the transposase piggyBac integrates at random into the genome of the human malaria parasite P. falciparum offering the possibility to develop forward genetic screens to analyse Plasmodium gene function. This study reports the development and application of the piggyBac transposition system for the rodent malaria parasite P. berghei and the evaluation of its potential as a tool in forward genetic studies. P. berghei is the most frequently used malaria parasite model in gene function analysis since phenotype screens throughout the complete Plasmodium life cycle are possible both in vitro and in vivo. Results We demonstrate that piggyBac based gene inactivation and promoter-trapping is both easier and more efficient in P. berghei than in the human malaria parasite, P. falciparum. Random piggyBac-mediated insertion into genes was achieved after parasites were transfected with the piggyBac donor plasmid either when transposase was expressed either from a helper plasmid or a stably integrated gene in the genome. Characterization of more than 120 insertion sites demonstrated that more than 70 most likely affect gene expression classifying their protein products as non-essential for asexual blood stage development. The non-essential nature of two of these genes was confirmed by targeted gene deletion one of which encodes P41, an ortholog of a human malaria vaccine candidate. Importantly for future development of whole genome phenotypic screens the remobilization of the piggyBac element in parasites that stably express transposase was demonstrated. Conclusion These data demonstrate that piggyBac behaved as an efficient and random transposon in P. berghei. Remobilization of piggyBac element shows that with further development the piggyBac system can be an effective tool to generate random genome-wide mutation parasite libraries, for use in large-scale phenotype screens in vitro and in vivo.

2011-01-01

177

The first insight into the Taxus genome via fosmid library construction and end sequencing  

Microsoft Academic Search

Taxus mairei is a critically endangered and commercially important cultured medicinal gymnosperm in China and forms an important medicinal\\u000a resource, but the research of its genome is absent. In this study, we constructed a T. mairei fosmid library and analyzed the fosmid end sequences to provide a preliminary assessment of the genome. The library consists\\u000a of one million clones with

DaCheng HaoLing; Ling Yang; PeiGen Xiao

2011-01-01

178

Democratizing Human Genome Project Information: A Model Program for Education, Information and Debate in Public Libraries.  

ERIC Educational Resources Information Center

|The "Mapping the Human Genome" project demonstrated that librarians can help whomever they serve in accessing information resources in the areas of biological and health information, whether it is the scientists who are developing the information or a member of the public who is using the information. Public libraries can guide library users…

Pollack, Miriam

179

Human genome libraries. Final progress report, February 1, 1994--August 31, 1997  

SciTech Connect

The goal of this program is to use a novel technology of chromosome microdissection and microcloning to construct chromosome region-specific libraries as resources for various human genome program studies. Region specific libraries have been constructed for the entire human chromosomes 2 and 18.

Kao, Fa-Ten

1998-01-01

180

Genotyping on High Throughput Sequencers: Preparation and Analysis of Reduced Representation Genomic Libraries  

PubMed Central

Next-generation sequencing of a reduced representation genomic library is a convenient approach for cataloging genetic variation in a set of samples, because fewer sequence reads are needed to obtain meaningful information compared to whole genome sequencing. Two popular approaches for creating reduced representation libraries are RAD-seq (sequencing of restriction-site associated DNA) and GBS (genotyping-by-sequencing). Both approaches sequence DNA that is flanking restriction sites across a genome, and allow the number of genomic fragments analyzed to be matched to the biological problem being studied. The typical workflow for creation of RAD-seq and GBS libraries will be discussed, with an emphasis on what instrumentation a core facility needs to start carrying out genotyping using these methods, and what factors need to be considered when initiating a project for a facility user. Case studies of using these methods for genotyping, trait mapping, meiotic map creation and genome assembly will be presented.

Rosato, Caprice; Etter, Paul; Kamps-Hughes, Nick; Johnson, Eric

2012-01-01

181

BAC array CGH in patients with Velocardiofacial syndrome-like features reveals genomic aberrations on chromosome region 1q21.1  

PubMed Central

Background Microdeletion of the chromosome 22q11.2 region is the most common genetic aberration among patients with velocardiofacial syndrome (VCFS) but a subset of subjects do not show alterations of this chromosome region. Methods We analyzed 18 patients with VCFS-like features by comparative genomic hybridisation (aCGH) array and performed a face-to-face slide hybridization with two different arrays: a whole genome and a chromosome 22-specific BAC array. Putative rearrangements were confirmed by FISH and MLPA assays. Results One patient carried a combination of rearrangements on 1q21.1, consisting in a microduplication of 212 kb and a close microdeletion of 1.15 Mb, previously reported in patients with variable phenotypes, including mental retardation, congenital heart defects (CHD) and schizophrenia. While 326 control samples were negative for both 1q21.1 rearrangements, one of 73 patients carried the same 212-kb microduplication, reciprocal to TAR microdeletion syndrome. Also, we detected four copy number variants (CNVs) inherited from one parent (a 744-kb duplication on 10q11.22; a 160 kb duplication and deletion on 22q11.21 in two cases; and a gain of 140 kb on 22q13.2), not present in control subjects, raising the potential role of these CNVs in the VCFS-like phenotype. Conclusions Our results confirmed aCGH as a successful strategy in order to characterize additional submicroscopic aberrations in patients with VCF-like features that fail to show alterations in 22q11.2 region. We report a 212-kb microduplication on 1q21.1, detected in two patients, which may contribute to CHD.

2009-01-01

182

Construction and characterization of an ovine bacterial artificial chromosome library  

Microsoft Academic Search

We have constructed a common bean (Phaseolus vulgarisL.) bacterial artificial chromosome (BAC) library con- sisting of 33 792 clones and an estimated 3- to 5-fold coverage of the common bean genome. Leaf nuclei were used as the source for high-molecular-weight DNA, and an endonuclease\\/methylase competition assay was employed to partially cleave the DNA. The library was screened with a number

Clare A. Gill; Scott K. Davis; Jeremy F. Taylor; Noelle E. Cockett; Cynthia D. K. Bottema

1999-01-01

183

Interpreting a Sequenced Genome: Toward a Cosmid Transgenic Library of Caenorhabditis elegans  

Microsoft Academic Search

We have generated a library of transgenic Caenorhabditis elegans strains that carry sequenced cosmids from the genome of the nematode. Each strain carries an extrachromosomal array containing a single cosmid, sequenced by the C. elegans Genome Sequencing Consortium, and a dominate Rol-6 marker. More than 500 transgenic strains representing 250 cosmids have been constructed. Collectively, these strains contain approximately 8

Diana L. Janke; Jacqueline E. Schein; Norman W. Franz; Nigel J. O'Neil; Greg P. Vatcher; Helen I. Stewart; Lynnette M. Kuervers; David L. Baillie; Ann M. Rose

2007-01-01

184

Mapping the Trypanosoma cruz i Genome : Analyses of Representative Cosmid Librarie s  

Microsoft Academic Search

In order to generate contiguous cosmid coverage of the genome of the protozoan parasite Trypanosoma cruz ifor large-scal e sequence analysis, a cosmid library o f 36 864 individual, primary clones was gen - erated. Total genomic DNA of the referenc e strain CL Brener was fragmented both b y partial digestion with Mbo I and by physica l shearing.

J. Hanke; D. O. Sánche; J. Henriksson; L. Ĺslund; U. Pettersson; A. C. C. Frasch; J. D. Hoheise

185

A new strategy for genome assembly using short sequence reads and reduced representation libraries  

PubMed Central

We have developed a novel approach for using massively parallel short-read sequencing to generate fast and inexpensive de novo genomic assemblies comparable to those generated by capillary-based methods. The ultrashort (<100 base) sequences generated by this technology pose specific biological and computational challenges for de novo assembly of large genomes. To account for this, we devised a method for experimentally partitioning the genome using reduced representation (RR) libraries prior to assembly. We use two restriction enzymes independently to create a series of overlapping fragment libraries, each containing a tractable subset of the genome. Together, these libraries allow us to reassemble the entire genome without the need of a reference sequence. As proof of concept, we applied this approach to sequence and assembled the majority of the 125-Mb Drosophila melanogaster genome. We subsequently demonstrate the accuracy of our assembly method with meaningful comparisons against the current available D. melanogaster reference genome (dm3). The ease of assembly and accuracy for comparative genomics suggest that our approach will scale to future mammalian genome-sequencing efforts, saving both time and money without sacrificing quality.

Young, Andrew L.; Abaan, Hatice Ozel; Zerbino, Daniel; Mullikin, James C.; Birney, Ewan; Margulies, Elliott H.

2010-01-01

186

Interplasmid transposition demonstrates piggyBac mobility in vertebrate species  

Microsoft Academic Search

The piggyBac transposon is an extremely versatile helper-dependent vector for gene transfer and germ line transformation in a wide range\\u000a of invertebrate species. Analyses of genome sequencing databases have identified piggyBac homologues among several sequenced animal genomes, including the human genome. In this report we demonstrate that this insect\\u000a transposon is capable of transposition in primate cells and embryos of

Neil F. Lobo; Tresa S. Fraser; John A. Adams; Malcolm J. Fraser Jr

2006-01-01

187

Transposon-mediated BAC transgenesis in zebrafish.  

PubMed

Bacterial artificial chromosomes (BACs) are widely used in studies of vertebrate gene regulation and function because they often closely recapitulate the expression patterns of endogenous genes. Here we report a step-by-step protocol for efficient BAC transgenesis in zebrafish using the medaka Tol2 transposon. Using recombineering in Escherichia coli, we introduce the iTol2 cassette in the BAC plasmid backbone, which contains the inverted minimal cis-sequences required for Tol2 transposition, and a reporter gene to replace a target locus in the BAC. Microinjection of the Tol2-BAC and a codon-optimized transposase mRNA into fertilized eggs results in clean integrations in the genome and transmission to the germline at a rate of ?15%. A single person can prepare a dozen constructs within 3 weeks, and obtain transgenic fish within approximately 3-4 months. Our protocol drastically reduces the labor involved in BAC transgenesis and will greatly facilitate biological and biomedical studies in model vertebrates. PMID:22134125

Suster, Maximiliano L; Abe, Gembu; Schouw, Anders; Kawakami, Koichi

2011-12-01

188

Genome-scale loss-of-function screening with a lentiviral RNAi library  

Microsoft Academic Search

The discovery that RNA interference (RNAi) is functional in mammalian cells led us to form The RNAi Consortium (TRC) with the goal of enabling large-scale loss-of-function screens through the development of genome-scale RNAi libraries and methodologies for their use. These resources form the basis of a loss-of-function screening platform created at the Broad Institute. Our human and mouse libraries currently

Nir Hacohen; William C Hahn; Eric S Lander; David M Sabatini; David E Root

2006-01-01

189

Isolation of Neurocysticercosis-Related Antigens from a Genomic Phage Display Library of Taenia solium  

Microsoft Academic Search

In this study, the authors have generated a tapeworm Taenia solium genomic DNA expression library where foreign peptides\\/ proteins were fused to N-termini of M13 cpVIII and expressed at a high copy number on the phage surface, and they showed that this library may be used in bioselection against antipathogen immune sera, allowing the identification of disease-related antigens recognizing antibodies

Erik González; Yetzi Robles; Tzipe Govezensky; Raul J. Bobes; Goar Gevorkian; Karen Manoutcharian

2010-01-01

190

Optimizing illumina next-generation sequencing library preparation for extremely at-biased genomes  

PubMed Central

Background Massively parallel sequencing technology is revolutionizing approaches to genomic and genetic research. Since its advent, the scale and efficiency of Next-Generation Sequencing (NGS) has rapidly improved. In spite of this success, sequencing genomes or genomic regions with extremely biased base composition is still a great challenge to the currently available NGS platforms. The genomes of some important pathogenic organisms like Plasmodium falciparum (high AT content) and Mycobacterium tuberculosis (high GC content) display extremes of base composition. The standard library preparation procedures that employ PCR amplification have been shown to cause uneven read coverage particularly across AT and GC rich regions, leading to problems in genome assembly and variation analyses. Alternative library-preparation approaches that omit PCR amplification require large quantities of starting material and hence are not suitable for small amounts of DNA/RNA such as those from clinical isolates. We have developed and optimized library-preparation procedures suitable for low quantity starting material and tolerant to extremely high AT content sequences. Results We have used our optimized conditions in parallel with standard methods to prepare Illumina sequencing libraries from a non-clinical and a clinical isolate (containing ~53% host contamination). By analyzing and comparing the quality of sequence data generated, we show that our optimized conditions that involve a PCR additive (TMAC), produces amplified libraries with improved coverage of extremely AT-rich regions and reduced bias toward GC neutral templates. Conclusion We have developed a robust and optimized Next-Generation Sequencing library amplification method suitable for extremely AT-rich genomes. The new amplification conditions significantly reduce bias and retain the complexity of either extremes of base composition. This development will greatly benefit sequencing clinical samples that often require amplification due to low mass of DNA starting material.

2012-01-01

191

Employing BAC-reporter constructs in the sea anemone Nematostella vectensis.  

PubMed

Changes in the expression and function of genes drive evolutionary change. Comparing how genes are regulated in different species is therefore becoming an important part of evo-devo studies. A key tool for investigating the regulation of genes is represented by bacterial artificial chromosomes (BAC)-reporter constructs. BACs are large insert libraries, often >100 kb, which thus capture the genomic sequences surrounding a gene of interest, including all, or nearly all, of the elements underpinning regulation. Recombinant BACs, containing a reporter gene in place of the endogenous coding sequence of genes, can be utilized to drive the expression of reporter genes under the regulatory control of the gene of interest while still embedded within its genomic context. Systematic deletions within the BAC-reporter construct can be used to identify the minimal reporter in an unbiased way, avoiding the risk of overlooking regulatory elements that may be many kilobases away from the transcription start-site. Nematostella vectensis (Edwardsiidae, Anthozoa, Cnidaria) has become an important model in regenerative biology, ecology, and especially in studies of evo-devo and gene-regulatory networks due to its interesting phylogenetic position and amenability to molecular techniques. The increasing interest in this rising model system also led to a demand for methods that can be used to study the regulation of genes in Nematostella. Here, we present our progress in employing BAC-reporter constructs to visualize gene-expression in Nematostella. Using a new Nematostella-specific recombination cassette, we made nine different BAC-reporter constructs. Although five BAC recombinants gave variable effects, three constructs, namely Nv-bra:eGFP::L10 BAC, Nv-dpp:eGFP::L10 BAC, and Nv-grm:eGFP::L10 BAC delivered promising results. We show that these three constructs express the reporter gene eGFP in 10.4-17.2% of all analyzed larvae, out of which 26.2-41.9% express GFP in a mosaic fashion within the expected domain. In addition to the expression within the known domains, we also observed cases of misexpression of eGFP and examples that could represent actual expression outside the described domain. Furthermore, we deep-sequenced and assembled five different BACs containing Nv-chordin, Nv-foxa, Nv-dpp, Nv-wnta, and Nv-wnt1, to improve assembly around these genes. The use of BAC-reporter constructs will foster cis-regulatory analyses in Nematostella and thus help to improve our understanding of the regulatory network in this cnidarian system. Ultimately, this will advance the comparison of gene-regulation across species and lead to a much better understanding of evolutionary changes and novelties. PMID:23956207

Fischer, Antje H L; Tulin, Sarah; Fredman, David; Smith, Joel

2013-08-16

192

Construction and characterization of a yeast artificial chromosome library containing seven haploid human genome equivalents  

SciTech Connect

Prior to constructing a library of yeast artificial chromosomes (YACs) containing very large human DNA fragments, the authors performed a series of preliminary experiments aimed at developing a suitable protocol. They found an inverse relationship between YAC insert size and transformation efficiency. Evidence of occasional rearrangement within YAC inserts was found resulting in clonally stable internal deletions or clonally unstable size variations. A protocol was developed for preparative electrophoretic enrichment of high molecular mass human DNA fragments from partial restriction digests and ligation with the YAC vector in agarose. A YAC library has been constructed from large fragments of DNA from an Epstein-Barr virus-transformed human lymphoblastoid cell line. The library presently contains 50,000 clones, 95% of which are greater than 250 kilobase pairs in size. The mean YAC size of the library, calculated from 132 randomly isolated clones, is 430 kilobase pairs. The library thus contains the equivalent of approximately seven haploid human genomes.

Albertsen, H.M.; Abderrahim, H.; Cann, H.M.; Dausset, J.; Le Paslier, D.; Cohen, D. (Centre d'Etude du Polymorphisme Humain, Paris (France))

1990-06-01

193

The complete genomes of three viruses assembled from shotgun libraries of marine RNA virus communities  

Microsoft Academic Search

BACKGROUND: RNA viruses have been isolated that infect marine organisms ranging from bacteria to whales, but little is known about the composition and population structure of the in situ marine RNA virus community. In a recent study, the majority of three genomes of previously unknown positive-sense single-stranded (ss) RNA viruses were assembled from reverse-transcribed whole-genome shotgun libraries. The present contribution

Alexander I Culley; Andrew S Lang; Curtis A Suttle

2007-01-01

194

Fosmid library end sequencing reveals a rarely known genome structure of marine shrimp Penaeus monodon  

Microsoft Academic Search

Background  The black tiger shrimp (Penaeus monodon) is one of the most important aquaculture species in the world, representing the crustacean lineage which possesses the greatest\\u000a species diversity among marine invertebrates. Yet, we barely know anything about their genomic structure. To understand the\\u000a organization and evolution of the P. monodon genome, a fosmid library consisting of 288,000 colonies and was constructed,

Shiao-Wei Huang; You-Yu Lin; En-Min You; Tze-Tze Liu; Hung-Yu Shu; Keh-Ming Wu; Shih-Feng Tsai; Chu-Fang Lo; Guang-Hsiung Kou; Gwo-Chin Ma; Ming Chen; Dongying Wu; Takashi Aoki; Ikuo Hirono; Hon-Tsen Yu

2011-01-01

195

Protective Activity of Streptococcus pneumoniae Spr1875 Protein Fragments Identified Using a Phage Displayed Genomic Library  

Microsoft Academic Search

There is considerable interest in pneumococcal protein antigens capable of inducing serotype-independent immunoprotection and of improving, thereby, existing vaccines. We report here on the immunogenic properties of a novel surface antigen encoded by ORF spr1875 in the R6 strain genome. An antigenic fragment encoded by spr1875, designated R4, was identified using a Streptococcus pneumoniae phage displayed genomic library after selection

Angela Cardaci; Salvatore Papasergi; Angelina Midiri; Giuseppe Mancuso; Maria Domina; Veronica Lanza Cariccio; Francesca Mandanici; Roberta Galbo; Carla Lo Passo; Ida Pernice; Paolo Donato; Susanna Ricci; Carmelo Biondo; Giuseppe Teti; Franco Felici; Concetta Beninati

2012-01-01

196

Transposon mediated BAC transgenesis via pronuclear injection of mouse zygotes.  

PubMed

Pronuclear microinjection of bacterial artificial chromosomes (BACs) is the preferred way to generate transgenic mice because the transgene accurately recapitulates expression of the endogenous gene. However, the method is demanding and the integrity and copy number of the BAC transgene is difficult to control. Here, we describe a simpler pronuclear injection method that relies on transposition to introduce full-length BACs into the mouse genome. The bacterial backbone of a hPAX6-GFP reporter BAC was retrofitted with PiggyBac transposon inverted terminal repeats and co-injected with PiggyBac transposase mRNA. Both the frequency of transgenic founders as well as intact, full-length, single copy integrations were increased. Transposition was determined by a rapid PCR screen for a transpositional signature and confirmation by splinkerette sequencing to show that the BACs were integrated as a single copy either in one or two different genomic sites. BAC transposons displayed improved functional accuracy over random integrants as evaluated by expression of the hPAX6-GFP reporter in embryonic neural tube and absence of ectopic expression. This method involves less work to achieve increased frequencies of both transgenesis and single copy, full-length integrations. These advantages are not only relevant to rodents but also for transgenesis in all systems. PMID:23225373

Rostovskaya, Maria; Naumann, Ronald; Fu, Jun; Obst, Mandy; Mueller, Doris; Stewart, A Francis; Anastassiadis, Konstantinos

2013-01-25

197

Construction and characterization of a common bean bacterial artificial chromosome library  

Microsoft Academic Search

We have constructed a common bean (Phaseolus vulgaris L.) bacterial artificial chromosome (BAC) library consisting of 33 792 clones and an estimated 3- to 5-fold coverage of the common bean genome. Leaf nuclei were used as the source for high-molecular-weight DNA, and an endonuclease\\/methylase competition assay was employed to partially cleave the DNA. The library was screened with a number

Wim Vanhouten; Sally MacKenzie

1999-01-01

198

Fight BAC!® Campaigns  

Center for Food Safety and Applied Nutrition (CFSAN)

... Fight BAC! Curriculum for Kids. Grades K-3 Exit Disclaimer; Grades 4-8 Exit Disclaimer; Grades 9-12 Exit Disclaimer. -. -. -. ... More results from www.fda.gov/food/foodborneillnesscontaminants/buystoreservesafefood

199

Characterization of Three Maize Bacterial Artificial Chromosome Libraries toward Anchoring of the Physical Map to the Genetic Map Using High-Density Bacterial Artificial Chromosome Filter Hybridization1  

PubMed Central

Three maize (Zea mays) bacterial artificial chromosome (BAC) libraries were constructed from inbred line B73. High-density filter sets from all three libraries, made using different restriction enzymes (HindIII, EcoRI, and MboI, respectively), were evaluated with a set of complex probes including the185-bp knob repeat, ribosomal DNA, two telomere-associated repeat sequences, four centromere repeats, the mitochondrial genome, a multifragment chloroplast DNA probe, and bacteriophage ?. The results indicate that the libraries are of high quality with low contamination by organellar and ?-sequences. The use of libraries from multiple enzymes increased the chance of recovering each region of the genome. Ninety maize restriction fragment-length polymorphism core markers were hybridized to filters of the HindIII library, representing 6× coverage of the genome, to initiate development of a framework for anchoring BAC contigs to the intermated B73 × Mo17 genetic map and to mark the bin boundaries on the physical map. All of the clones used as hybridization probes detected at least three BACs. Twenty-two single-copy number core markers identified an average of 7.4 ± 3.3 positive clones, consistent with the expectation of six clones. This information is integrated into fingerprinting data generated by the Arizona Genomics Institute to assemble the BAC contigs using fingerprint contig and contributed to the process of physical map construction.

Yim, Young-Sun; Davis, Georgia L.; Duru, Ngozi A.; Musket, Theresa A.; Linton, Eric W.; Messing, Joachim W.; McMullen, Michael D.; Soderlund, Carol A.; Polacco, Mary L.; Gardiner, Jack M.; Coe, Edward H.

2002-01-01

200

A Genome-Wide Survey of Switchgrass Genome Structure and Organization  

PubMed Central

The perennial grass, switchgrass (Panicum virgatum L.), is a promising bioenergy crop and the target of whole genome sequencing. We constructed two bacterial artificial chromosome (BAC) libraries from the AP13 clone of switchgrass to gain insight into the genome structure and organization, initiate functional and comparative genomic studies, and assist with genome assembly. Together representing 16 haploid genome equivalents of switchgrass, each library comprises 101,376 clones with average insert sizes of 144 (HindIII-generated) and 110 kb (BstYI-generated). A total of 330,297 high quality BAC-end sequences (BES) were generated, accounting for 263.2 Mbp (16.4%) of the switchgrass genome. Analysis of the BES identified 279,099 known repetitive elements, >50,000 SSRs, and 2,528 novel repeat elements, named switchgrass repetitive elements (SREs). Comparative mapping of 47 full-length BAC sequences and 330K BES revealed high levels of synteny with the grass genomes sorghum, rice, maize, and Brachypodium. Our data indicate that the sorghum genome has retained larger microsyntenous regions with switchgrass besides high gene order conservation with rice. The resources generated in this effort will be useful for a broad range of applications.

Sharma, Manoj K.; Sharma, Rita; Cao, Peijian; Jenkins, Jerry; Bartley, Laura E.; Qualls, Morgan; Grimwood, Jane; Schmutz, Jeremy; Rokhsar, Daniel; Ronald, Pamela C.

2012-01-01

201

PiggyBac toolbox.  

PubMed

The PiggyBac (PB) transposon system was originally derived from the cabbage looper moth Trichoplusia ni and represents one of the most promising transposon systems to date. Engineering of the PB transposase enzyme (PBase) and its cognate transposon DNA elements resulted in a substantial increase in transposition activities. Consequently, this has greatly enhanced the versatility of the PB toolbox. It is now widely used for stable gene delivery into a broad variety of cell types from different species, including mammalian cells. This opened up new perspectives for potential therapeutic applications in the fields of gene therapy and regenerative medicine. In particular, we have recently demonstrated that PB transposons could be used to stably deliver genes into human CD34(+) hematopoietic stem cells (HSCs) resulting in sustained transgene expression in its differentiated progeny. The PB transposon system is particularly attractive for the generation of induced pluripotent stem cells (iPS). Typically, this can be accomplished by stable gene transfer of genes encoding one or more reprogramming factors (i.e., c-MYC, KLF-4, OCT-4, and/or SOX-2). We have generated a PB-based nonviral reprogramming toolbox that contains different combinations of these reprogramming genes. The main advantage of using this PB toolbox for iPS generation is that the reprogramming cassette can be excised by de novo transposase expression, without leaving any molecular trace in the target cell genome. This "traceless excision" paradigm obviates potential risks associated with inadvertent re-expression of reprogramming factors in the iPS progeny. These various applications in gene therapy, stem cell engineering, and regenerative medicine underscore the emerging versatility of the PB toolbox. PMID:22367876

Di Matteo, Mario; Mátrai, Janka; Belay, Eyayu; Firdissa, Tewodros; Vandendriessche, Thierry; Chuah, Marinee K L

2012-01-01

202

Strategy to sequence the genome of Corynebacterium glutamicum ATCC 13032: use of a cosmid and a bacterial artificial chromosome library  

Microsoft Academic Search

The initial strategy of the Corynebacterium glutamicum genome project was to sequence overlapping inserts of an ordered cosmid library. High-density colony grids of approximately 28 genome equivalents were used for the identification of overlapping clones by Southern hybridization. Altogether 18 contiguous genomic segments comprising 95 overlapping cosmids were assembled. Systematic shotgun sequencing of the assembled cosmid set revealed that only

Andreas Tauch; Iris Homann; Sascha Mormann; Silvia Rüberg; Alain Billault; Brigitte Bathe; Sven Brand; Olaf Brockmann-Gretza; Christian Rückert; Natalie Schischka; Carsten Wrenger; Jörg Hoheisel; Bettina Möckel; Klaus Huthmacher; Walter Pfefferle; Alfred Pühler; Jörn Kalinowski

2002-01-01

203

Recent Advances in Cotton Genomics  

PubMed Central

Genome research promises to promote continued and enhanced plant genetic improvement. As a world's leading crop and a model system for studies of many biological processes, genomics research of cottons has advanced rapidly in the past few years. This article presents a comprehensive review on the recent advances of cotton genomics research. The reviewed areas include DNA markers, genetic maps, mapped genes and QTLs, ESTs, microarrays, gene expression profiling, BAC and BIBAC libraries, physical mapping, genome sequencing, and applications of genomic tools in cotton breeding. Analysis of the current status of each of the genome research areas suggests that the areas of physical mapping, QTL fine mapping, genome sequencing, nonfiber and nonovule EST development, gene expression profiling, and association studies between gene expression and fiber trait performance should be emphasized currently and in near future to accelerate utilization of the genomics research achievements for enhancing cotton genetic improvement.

Zhang, Hong-Bin; Li, Yaning; Wang, Baohua; Chee, Peng W.

2008-01-01

204

Alignment of the genomes of Brachypodium distachyon and temperate cereals and grasses using bacterial artificial chromosome landing with fluorescence in situ hybridization.  

PubMed

As part of an initiative to develop Brachypodium distachyon as a genomic "bridge" species between rice and the temperate cereals and grasses, a BAC library has been constructed for the two diploid (2n = 2x = 10) genotypes, ABR1 and ABR5. The library consists of 9100 clones, with an approximate average insert size of 88 kb, representing 2.22 genome equivalents. To validate the usefulness of this species for comparative genomics and gene discovery in its larger genome relatives, the library was screened by PCR using primers designed on previously mapped rice and Poaceae sequences. Screening indicated a degree of synteny between these species and B. distachyon, which was confirmed by fluorescent in situ hybridization of the marker-selected BACs (BAC landing) to the 10 chromosome arms of the karyotype, with most of the BACs hybridizing as single loci on known chromosomes. Contiguous BACs colocalized on individual chromosomes, thereby confirming the conservation of genome synteny and proving that B. distachyon has utility as a temperate grass model species alternative to rice. PMID:16489232

Hasterok, Robert; Marasek, Agnieszka; Donnison, Iain S; Armstead, Ian; Thomas, Ann; King, Ian P; Wolny, Elzbieta; Idziak, Dominika; Draper, John; Jenkins, Glyn

2006-02-19

205

Molecular analysis of DNA and construction of genomic libraries of Mycobacterium leprae.  

PubMed Central

Molecular analysis of DNA from Mycobacterium leprae, "Mycobacterium lufu," and Mycobacterium vaccae has demonstrated that the G + C (guanine plus cytosine) contents of the DNAs are 56, 61, and 65%, respectively, and that the genome sizes are 2.2 X 10(9), 3.1 X 10(9), and 3.1 X 10(9) daltons, respectively. Because of the significant differences in both G + C content and genome size among M. leprae, "M. lufu," and M. vaccae DNAs, these species are not related, although hybridization experiments under nonstringent conditions, with two separate cloned M. leprae DNA inserts as probes, indicate that there are some conserved sequences among the DNAs. The G + C content of Dasypus novemcinctus (armadillo, the animal of choice for cultivating M. leprae) DNA was determined to be 36%. Genomic libraries potentially representing more than 99.99% of each genome were prepared by cloning into the cosmid vector, pHC79, in Escherichia coli K-12. A genomic library representing approximately 95% of the genome of M. vaccae was prepared in pBR322. M. leprae DNA was subcloned from the pHC79::M. leprae library into an expression vector, pYA626. This vector is a 3.8-kilobase derivative of pBR322 in which the promoter region of the asd (aspartate semialdehyde dehydrogenase) gene from Streptococcus mutans has been inserted in place of the EcoRI-to-PstI fragment of pBR322. Several (44% of those tested) pYA626::M. leprae recombinants and one pBR322::M. vaccae recombinant synthesized new polypeptides in minicells of E. coli, indicating that mycobacterial DNA can be expressed in E. coli K-12, although expression is probably dependent upon use of nonmycobacterial promoters recognized by the E. coli transcription-translation apparatus. Images

Clark-Curtiss, J E; Jacobs, W R; Docherty, M A; Ritchie, L R; Curtiss, R

1985-01-01

206

A genome-wide library of CB4856\\/N2 introgression lines of Caenorhabditis elegans  

Microsoft Academic Search

Recombinant inbred lines (RILs) derived from Caenorhabditis elegans wild-type N2 and CB4856 are increasingly being used for mapping genes underlying complex traits. To speed up mapping and gene discovery, introgression lines (ILs) offer a powerful tool for more efficient QTL identification. We constructed a library of 90 ILs, each carrying a single homozygous CB4856 genomic segment introgressed into the genetic

Agnieszka Doroszuk; L. Basten Snoek; Emilie Fradin; Joost Riksen; Jan Kammenga

2009-01-01

207

Design and evaluation of genome-wide libraries for RNA interference screens  

Microsoft Academic Search

RNA interference (RNAi) screens have enabled the systematic analysis of many biological processes in cultured cells and whole\\u000a organisms. The success of such screens and the interpretation of the data depend on the stringent design of RNAi libraries.\\u000a We describe and validate NEXT-RNAi, a software for the automated design and evaluation of RNAi sequences on a genome-wide\\u000a scale. NEXT-RNAi is

Thomas Horn; Thomas Sandmann; Michael Boutros

2010-01-01

208

Chromosome region-specific libraries for human genome analysis. Final progress report, 1 March 1991--28 February 1994.  

National Technical Information Service (NTIS)

The objectives of this grant proposal include (1) development of a chromosome microdissection and PCR-mediated microcloning technology, (2) application of this microtechnology to the construction of region-specific libraries for human genome analysis. Dur...

F. T. Kao

1994-01-01

209

Library+  

ERIC Educational Resources Information Center

|This article discusses possible future directions for academic libraries in the post Web/Library 2.0 world. These possible directions include areas such as data literacy, linked data sets, and opportunities for libraries in support of digital humanities. The author provides a brief sketch of the background information regarding the topics and…

Merrill, Alex

2011-01-01

210

The first insight into the Taxus genome via fosmid library construction and end sequencing.  

PubMed

Taxus mairei is a critically endangered and commercially important cultured medicinal gymnosperm in China and forms an important medicinal resource, but the research of its genome is absent. In this study, we constructed a T. mairei fosmid library and analyzed the fosmid end sequences to provide a preliminary assessment of the genome. The library consists of one million clones with an average insert size of about 39 kb, amounting to 3.9 genome equivalents. Fosmid stability assays indicate that T. mairei DNA was stable during propagation in the fosmid system. End sequencing of both 5' and 3' ends of 968 individual clones generated 1,923 sequences after trimming, with an average sequence length of 839 bp. BLASTN searches of the nr and EST databases of GenBank and BLASTX searches of the nr database resulted in 560 (29.1%) significant hits (E < e(-5)). Repetitive sequences analysis revealed that 20.8% of end sequences are repetitive elements, which were composed of retroelements, DNA transposons, satellites, simple repeats, and low complexity sequences. The distribution pattern of various repeat types was found to be more similar to the gymnosperm Pinus and Picea than to the monocot and dicot. The satellites of T. mairei were significantly longer than those of P. taeda and P. glauca. The tetra-nucleotide repeats of T. mairei were much longer than those of P. glauca and P. taeda. The fosmid library and the fosmid end sequences, for the first time, will serve as a useful resource for large-scale genome sequencing, physical mapping, SSR marker development and positional cloning, and provide a better understanding of the Taxus genome. PMID:21207064

Hao, DaCheng; Yang, Ling; Xiao, PeiGen

2011-01-05

211

Construction of chromosome-specific DNA libraries covering the whole genome of field bean ( Vicia faba L.)  

Microsoft Academic Search

Recombinant DNA libraries were constructed for seven chromosome types isolated from two translocation lines of field bean (Vicia faba L.) with reconstructed karyotypes. The chromosomes were selected so that the set of libraries covers the wholeV. faba genome more than once. Individual chromosome types were highly purified by flow sorting, and their DNA was amplified by degenerate oligonucleotideprimed (DOP) polymerase

J. Macas; G. Gualberti; M. Nouzová; P. Samec; S. Lucretti; J. Doležel

1996-01-01

212

End-sequencing and characterization of silkworm (Bombyx mori) bacterial artificial chromosome libraries  

PubMed Central

Background We performed large-scale bacterial artificial chromosome (BAC) end-sequencing of two BAC libraries (an EcoRI- and a BamHI-digested library) and conducted an in silico analysis to characterize the obtained sequence data, to make them a useful resource for genomic research on the silkworm (Bombyx mori). Results More than 94000 BAC end sequences (BESs), comprising more than 55 Mbp and covering about 10.4% of the silkworm genome, were sequenced. Repeat-sequence analysis with known repeat sequences indicated that the long interspersed nuclear elements (LINEs) were abundant in BamHI BESs, whereas DNA-type elements were abundant in EcoRI BESs. Repeat-sequence analysis revealed that the abundance of LINEs might be due to a GC bias of the restriction sites and that the GC content of silkworm LINEs was higher than that of mammalian LINEs. In a BLAST-based sequence analysis of the BESs against two available whole-genome shotgun sequence data sets, more than 70% of the BESs had a BLAST hit with an identity of ? 99%. About 14% of EcoRI BESs and about 8% of BamHI BESs were paired-end clones with unique sequences at both ends. Cluster analysis of the BESs clarified the proportion of BESs containing protein-coding regions. Conclusion As a result of this characterization, the identified BESs will be a valuable resource for genomic research on Bombyx mori, for example, as a base for construction of a BAC-based physical map. The use of multiple complementary BAC libraries constructed with different restriction enzymes also makes the BESs a more valuable genomic resource. The GenBank accession numbers of the obtained end sequences are DE283657–DE378560.

Suetsugu, Yoshitaka; Minami, Hiroshi; Shimomura, Michihiko; Sasanuma, Shun-ichi; Narukawa, Junko; Mita, Kazuei; Yamamoto, Kimiko

2007-01-01

213

A Novel Helper Phage Enabling Construction of Genome-Scale ORF-Enriched Phage Display Libraries  

PubMed Central

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.

Grover, Payal; Singh, Ajay; Mathur, Kapil; Verma, Vaishali; Kaur, Charanpreet; Chaudhary, Vijay K.

2013-01-01

214

Engineering BAC reporter gene constructs for mouse transgenesis.  

PubMed

A culmination of large-scale ideas and efforts has truly allowed for the use of large genomic DNA clones housed in Bacterial Artificial Chromosome (BAC) vectors for biological research. Fundamental advances that have allowed this to happen include (1) the completion of genome sequencing projects and the establishment of highly annotated web-accessible databases allowing for the rapid identity and purchase of BAC clones containing genes of interest. (2) The generation of methodologies to modify BACs genetically, allowing for the rapid creation of gene targeting constructs or transgenic reporter gene constructs using homologous recombination in bacteria.Recent efforts on our part have capitalized on these advances by using BACs and bacterial recombination methods to generate fluorescent protein reporter transgenic mice to study skeletal biology. The rationale for using BAC genomic DNA clones to engineer reporter gene constructs is based on their much larger size, thus increasing the likelihood that most, if not all, of a gene's respective cis regulator elements are present, giving a truer representation of the endogenous gene's expression. In a relatively short amount of time, we have become extremely proficient at generating BAC reporters. Contrary to the widely perceived notion that working with BACs is complex and difficult, we decided to write this chapter to encourage laboratories that are currently using traditional molecular cloning methods to engineer transgenic DNA constructs to strongly consider learning BAC methodologies. As an example, we walk through the steps we took to generate the transgenic reporter mouse line, Tenascin C (TNC)-mCherry. PMID:21080280

Fu, Yu; Maye, Peter

2011-01-01

215

Dynamics of Genomic-Library Enrichment and Identification of Solvent Tolerance Genes for Clostridium acetobutylicum? †  

PubMed Central

A Clostridium acetobutylicum ATCC 824 genomic library was constructed using randomly sheared DNA. Library inserts conferring increased tolerance to 1-butanol were isolated using two protocols. Protocol I utilized a single round of butanol challenges in batch culture, while protocol II, which gave clearly superior outcomes, was based on the serial transfer of stationary-phase cultures into progressively higher butanol concentrations. DNA microarray analysis made a high-resolution assessment of the dynamic process of library enrichment possible for the first time. Protocol I yielded a library insert containing the entire coding region of the gene CAC0003 (which codes for a protein of unknown function) but also several DNA fragments containing promoter regions. Protocol II enabled the successful identification of DNA fragments containing several intact genes conferring preferential growth under conditions of butanol stress. Since expression using the employed library is possible only from natural promoters, among the enriched genes, we identified 16 genes that constitute the first cistron of a transcriptional unit. These genes include four transcriptional regulators (CAC0977, CAC1463, CAC1869, and CAC2495). After subcloning plasmids carrying the CAC0003 and CAC1869 genes, strains 824(pCAC0003) and 824(pCAC1869) exhibited 13% and an 81% increases, respectively, in butanol tolerance relative to the plasmid control strain. 824(pCAC1869) consistently grew to higher cell densities in challenged and unchallenged cultures and exhibited prolonged metabolism. Our serial enrichment approach provided a more detailed understanding of the dynamic process of library enrichment under conditions of selective growth. Further characterization of the genes identified in this study will likely enhance our understanding of the complex phenotype of solvent tolerance.

Borden, Jacob R.; Papoutsakis, Eleftherios Terry

2007-01-01

216

The complete genomes of three viruses assembled from shotgun libraries of marine RNA virus communities  

PubMed Central

Background RNA viruses have been isolated that infect marine organisms ranging from bacteria to whales, but little is known about the composition and population structure of the in situ marine RNA virus community. In a recent study, the majority of three genomes of previously unknown positive-sense single-stranded (ss) RNA viruses were assembled from reverse-transcribed whole-genome shotgun libraries. The present contribution comparatively analyzes these genomes with respect to representative viruses from established viral taxa. Results Two of the genomes (JP-A and JP-B), appear to be polycistronic viruses in the proposed order Picornavirales that fall into a well-supported clade of marine picorna-like viruses, the characterized members of which all infect marine protists. A temporal and geographic survey indicates that the JP genomes are persistent and widespread in British Columbia waters. The third genome, SOG, encodes a putative RNA-dependent RNA polymerase (RdRp) that is related to the RdRp of viruses in the family Tombusviridae, but the remaining SOG sequence has no significant similarity to any sequences in the NCBI database. Conclusion The complete genomes of these viruses permitted analyses that resulted in a more comprehensive comparison of these pathogens with established taxa. For example, in concordance with phylogenies based on the RdRp, our results support a close homology between JP-A and JP-B and RsRNAV. In contrast, although classification of the SOG genome based on the RdRp places SOG within the Tombusviridae, SOG lacks a capsid and movement protein conserved within this family and SOG is thus likely more distantly related to the Tombusivridae than the RdRp phylogeney indicates.

Culley, Alexander I; Lang, Andrew S; Suttle, Curtis A

2007-01-01

217

From the ORFeome concept to highly comprehensive, full-genome screening libraries.  

PubMed

Recombination-based cloning techniques have in recent times facilitated the establishment of genome-scale single-gene ORFeome repositories. Their further handling and downstream application in systematic fashion is, however, practically impeded because of logistical plus economic challenges. At this juncture, simultaneously transferring entire gene collections in compiled pool format could represent an advanced compromise between systematic ORFeome (an organism's entire set of protein-encoding open reading frames) projects and traditional random library approaches, but has not yet been considered in great detail. In our endeavor to merge the comprehensiveness of ORFeomes with a basically simple, streamlined, and easily executable single-tube design, we have here produced five different pooled screening-ready libraries for both Staphylococcus aureus and Homo sapiens. By evaluating the parallel transfer efficiencies of differentially sized genes from initial polymerase chain reaction (PCR) product amplification to entry and final destination library construction via quantitative real-time PCR, we found that the complexity of the gene population is fairly stably maintained once an entry resource has been successfully established, and that no apparent size-selection bias loss of large inserts takes place. Recombinational transfer processes are hence robust enough for straightforwardly achieving such pooled screening libraries. PMID:22621725

Rid, Raphaela; Abdel-Hadi, Omar; Maier, Richard; Wagner, Martin; Hundsberger, Harald; Hintner, Helmut; Bauer, Johann; Onder, Kamil

2012-05-23

218

Physical mapping and microsynteny of Brassica rapa ssp. pekinensis genome corresponding to a 222 kbp gene-rich region of Arabidopsis chromosome 4 and partially duplicated on chromosome 5  

Microsoft Academic Search

We constructed a bacterial artificial chromosome (BAC) library, designated as KBrH, from high molecular weight genomic DNA\\u000a of Brassica rapa ssp. pekinensis (Chinese cabbage). This library, which was constructed using HindIII-cleaved genomic DNA, consists of 56,592 clones with average insert size of 115 kbp. Using a partially duplicated DNA\\u000a sequence of Arabidopsis, represented by 19 and 9 predicted genes on chromosome

J. Y. Park; D. H. Koo; C. P. Hong; S. J. Lee; J. W. Jeon; S. H. Lee; P. Y. Yun; B. S. Park; H. R. Kim; J. W. Bang; P. Plaha; I. Bancroft; Y. P. Lim

2005-01-01

219

Exploiting chemical libraries, structure, and genomics in the search for kinase inhibitors.  

PubMed

Selective protein kinase inhibitors were developed on the basis of the unexpected binding mode of 2,6,9-trisubstituted purines to the adenosine triphosphate-binding site of the human cyclin-dependent kinase 2 (CDK2). By iterating chemical library synthesis and biological screening, potent inhibitors of the human CDK2-cyclin A kinase complex and of Saccharomyces cerevisiae Cdc28p were identified. The structural basis for the binding affinity and selectivity was determined by analysis of a three-dimensional crystal structure of a CDK2-inhibitor complex. The cellular effects of these compounds were characterized in mammalian cells and yeast. In the latter case the effects were characterized on a genome-wide scale by monitoring changes in messenger RNA levels in treated cells with high-density oligonucleotide probe arrays. Purine libraries could provide useful tools for analyzing a variety of signaling and regulatory pathways and may lead to the development of new therapeutics. PMID:9677190

Gray, N S; Wodicka, L; Thunnissen, A M; Norman, T C; Kwon, S; Espinoza, F H; Morgan, D O; Barnes, G; LeClerc, S; Meijer, L; Kim, S H; Lockhart, D J; Schultz, P G

1998-07-24

220

Development of a pooled probe method for locating small gene families in a physical map of soybean using stress related paralogues and a BAC minimum tile path  

PubMed Central

Background Genome analysis of soybean (Glycine max L.) has been complicated by its paleo-autopolyploid nature and conserved homeologous regions. Landmarks of expressed sequence tags (ESTs) located within a minimum tile path (MTP) of contiguous (contig) bacterial artificial chromosome (BAC) clones or radiation hybrid set can identify stress and defense related gene rich regions in the genome. A physical map of about 2,800 contigs and MTPs of 8,064 BAC clones encompass the soybean genome. That genome is being sequenced by whole genome shotgun methods so that reliable estimates of gene family size and gene locations will provide a useful tool for finishing. The aims here were to develop methods to anchor plant defense- and stress-related gene paralogues on the MTP derived from the soybean physical map, to identify gene rich regions and to correlate those with QTL for disease resistance. Results The probes included 143 ESTs from a root library selected by subtractive hybridization from a multiply disease resistant soybean cultivar 'Forrest' 14 days after inoculation with Fusarium solani f. sp. glycines (F. virguliforme). Another 166 probes were chosen from a root EST library (Gm-r1021) prepared from a non-inoculated soybean cultivar 'Williams 82' based on their homology to the known defense and stress related genes. Twelve and thirteen pooled EST probes were hybridized to high-density colony arrays of MTP BAC clones from the cv. 'Forrest' genome. The EST pools located 613 paralogues for 201 of the 309 probes used (range 1–13 per functional probe). One hundred BAC clones contained more than one kind of paralogue. Many more BACs (246) contained a single paralogue of one of the 201 probes detectable gene families. ESTs were anchored on soybean linkage groups A1, B1, C2, E, D1a+Q, G, I, M, H, and O. Conclusion Estimates of gene family sizes were more similar to those made by Southern hybridization than by bioinformatics inferences from EST collections. When compared to Arabidopsis thaliana there were more 2 and 4 member paralogue families reflecting the diploidized-tetraploid nature of the soybean genome. However there were fewer families with 5 or more genes and the same number of single genes. Therefore the method can identify evolutionary patterns such as massively extensive selective gene loss or rapid divergence to regenerate the unique genes in some families.

Shopinski, Kay L; Iqbal, Muhammad J; Shultz, Jeffry L; Jayaraman, Dheepakkumaran; Lightfoot, David A

2006-01-01

221

PiggyBac Transposon-mediated Gene Transfer in Human Cells  

Microsoft Academic Search

Transposons are mobile genetic elements that can be used to integrate transgenes into host cell genomes. The piggyBac transposon system has been used for transgenesis of insects and for germline mutagenesis in mice. We compared transposition activity of piggyBac with Sleeping Beauty (SB), a widely used transposon system for preclinical gene therapy studies. An engineered piggyBac transposon with minimal length

Matthew H Wilson; Craig J Coates; Alfred L George

2007-01-01

222

Construction of bacterial artificial chromosome libraries for two model fish species: the Lake Malawi cichlid (Metriaclima zebra), and the blind cavefish (Astyanax mexicanus)  

Microsoft Academic Search

Abstract Teleost fishes have become,important models,for studying the evolution of the genetic mechanisms,of development. A key resource for comparative,genomics,and positional cloning are large-insert libraries constructed in bacterial artificial chromosomes., We have constructed BAC libraries for two species of teleost fish that are important models for the study of developmental,evolution. Metriaclima zebra is one of several hundred closely-related, morphologically diverse haplochromine

Federica DiPalma; Celeste Kidd; Richard Borowsky; Thomas D. Kocher

223

Germ-line transformation of the Queensland fruit fly, Bactrocera tryoni, using a piggyBac vector in the presence of endogenous piggyBac elements.  

PubMed

We report the heritable germ-line transformation of the Queensland fruit fly, Bactrocera tryoni, using a piggyBac vector marked with either the fluorescent protein DsRed or EGFP. A transformation frequency of 5-10% was obtained. Inheritance of the transgenes has remained stable over more than 15 generations despite the presence of endogenous piggyBac sequences in the B. tryoni genome. The sequence of insertion sites shows the usual canonical pattern of piggyBac integraton into TTAA target sites. An investigation of endogenous piggyBac elements in the B. tryoni genome reveals the presence of sequences almost identical to those reported recently for the B. dorsalis complex of fruit flies and two noctuid moths, suggesting a common origin of piggyBac sequences in these species. The availability of transformation protocols for B. tryoni has the potential to deliver improvements in the performance of the Sterile Insect Technique for this pest species. PMID:20859652

Raphael, K A; Shearman, D C A; Streamer, K; Morrow, J L; Handler, A M; Frommer, M

2010-09-22

224

Genome wide SNP discovery in flax through next generation sequencing of reduced representation libraries  

PubMed Central

Background Flax (Linum usitatissimum L.) is a significant fibre and oilseed crop. Current flax molecular markers, including isozymes, RAPDs, AFLPs and SSRs are of limited use in the construction of high density linkage maps and for association mapping applications due to factors such as low reproducibility, intense labour requirements and/or limited numbers. We report here on the use of a reduced representation library strategy combined with next generation Illumina sequencing for rapid and large scale discovery of SNPs in eight flax genotypes. SNP discovery was performed through in silico analysis of the sequencing data against the whole genome shotgun sequence assembly of flax genotype CDC Bethune. Genotyping-by-sequencing of an F6-derived recombinant inbred line population provided validation of the SNPs. Results Reduced representation libraries of eight flax genotypes were sequenced on the Illumina sequencing platform resulting in sequence coverage ranging from 4.33 to 15.64X (genome equivalents). Depending on the relatedness of the genotypes and the number and length of the reads, between 78% and 93% of the reads mapped onto the CDC Bethune whole genome shotgun sequence assembly. A total of 55,465 SNPs were discovered with the largest number of SNPs belonging to the genotypes with the highest mapping coverage percentage. Approximately 84% of the SNPs discovered were identified in a single genotype, 13% were shared between any two genotypes and the remaining 3% in three or more. Nearly a quarter of the SNPs were found in genic regions. A total of 4,706 out of 4,863 SNPs discovered in Macbeth were validated using genotyping-by-sequencing of 96 F6 individuals from a recombinant inbred line population derived from a cross between CDC Bethune and Macbeth, corresponding to a validation rate of 96.8%. Conclusions Next generation sequencing of reduced representation libraries was successfully implemented for genome-wide SNP discovery from flax. The genotyping-by-sequencing approach proved to be efficient for validation. The SNP resources generated in this work will assist in generating high density maps of flax and facilitate QTL discovery, marker-assisted selection, phylogenetic analyses, association mapping and anchoring of the whole genome shotgun sequence.

2012-01-01

225

TOWARD AN INTEGRATED PHYSICAL AND GENETIC MAP OF THE CULTIVATED COTTON GENOME: PHYSICAL MAP CONTIG ASSEMBLING AND ANCHORING TO ITS SUBGENOMES  

Technology Transfer Automated Retrieval System (TEKTRAN)

We are developing an integrated physical and genetic map of the cultivated allotetraploid cotton (AD genomes) using three large-insert BAC and BIBAC libraries that were constructed from the genetic standard line TM-1 (G. hirsutum). An automated procedure previously developed and tested in both human...

226

Identifying microbial fitness determinants by Insertion Sequencing (INSeq) using genome-wide transposon mutant libraries  

PubMed Central

Insertion Sequencing (INSeq) is a method for determining the insertion site and relative abundance of large numbers of transposon mutants in a mixed population of isogenic mutants of a sequenced microbial species. INSeq is based on a modified mariner transposon containing MmeI sites at its ends, allowing cleavage at chromosomal sites 16–17bp from the inserted transposon. Genomic regions adjacent to the transposons are amplified by linear PCR with a biotinylated primer. Products are bound to magnetic beads, digested with MmeI, and barcoded with sample-specific linkers appended to each restriction fragment. After limited PCR amplification, fragments are sequenced using a high-throughput instrument. The sequence of each read can be used to map the location of a transposon in the genome. Read count measures the relative abundance of that mutant in the population. Solid-phase library preparation makes this protocol rapid (18h), easy to scale-up, amenable to automation, and useful for a variety of samples. A protocol for characterizing libraries of transposon mutant strains clonally arrayed in multi-well format is provided.

Goodman, Andrew L.; Wu, Meng; Gordon, Jeffrey I.

2012-01-01

227

Identifying microbial fitness determinants by insertion sequencing using genome-wide transposon mutant libraries.  

PubMed

Insertion sequencing (INSeq) is a method for determining the insertion site and relative abundance of large numbers of transposon mutants in a mixed population of isogenic mutants of a sequenced microbial species. INSeq is based on a modified mariner transposon containing MmeI sites at its ends, allowing cleavage at chromosomal sites 16-17 bp from the inserted transposon. Genomic regions adjacent to the transposons are amplified by linear PCR with a biotinylated primer. Products are bound to magnetic beads, digested with MmeI and barcoded with sample-specific linkers appended to each restriction fragment. After limited PCR amplification, fragments are sequenced using a high-throughput instrument. The sequence of each read can be used to map the location of a transposon in the genome. Read count measures the relative abundance of that mutant in the population. Solid-phase library preparation makes this protocol rapid (18 h), easy to scale up, amenable to automation and useful for a variety of samples. A protocol for characterizing libraries of transposon mutant strains clonally arrayed in a multiwell format is provided. PMID:22094732

Goodman, Andrew L; Wu, Meng; Gordon, Jeffrey I

2011-11-17

228

Rapid Communication Stable transformation of a Mamestra brassicae (lepidoptera) cell line with the lepidopteran-derived transposon piggyBac  

Microsoft Academic Search

Cabbage moth cells were transfected with the vector pBac{3xP3-EGFPafm} and helper phsp-pBac. Seventeen percent of the transfected cells showed stable EGFP-expression. This indicates successful and stable transformation of M. brassicae cells with a piggyBac-derived vector. Genomic integration of Bac{3xP3-EGFPafm}in stably transformed cells was confirmed by Southern blots and inverse PCR. Since the integrations are stable, and transfection with pBac{3xP3-EGFPafm} alone

Mauro Mandrioli; Ernst A. Wimmer

229

BAC array CGH in patients with Velocardiofacial syndrome-like features reveals genomic aberrations on chromosome region 1q21.1  

Microsoft Academic Search

BACKGROUND: Microdeletion of the chromosome 22q11.2 region is the most common genetic aberration among patients with velocardiofacial syndrome (VCFS) but a subset of subjects do not show alterations of this chromosome region. METHODS: We analyzed 18 patients with VCFS-like features by comparative genomic hybridisation (aCGH) array and performed a face-to-face slide hybridization with two different arrays: a whole genome and

Anna Brunet; Lluís Armengol; Damiŕ Heine; Jordi Rosell; Manel García-Aragonés; Elisabeth Gabau; Xavier Estivill; Miriam Guitart

2009-01-01

230

Functional screening of metagenome and genome libraries for detection of novel flavonoid-modifying enzymes.  

PubMed

The functional detection of novel enzymes other than hydrolases from metagenomes is limited since only a very few reliable screening procedures are available that allow the rapid screening of large clone libraries. For the discovery of flavonoid-modifying enzymes in genome and metagenome clone libraries, we have developed a new screening system based on high-performance thin-layer chromatography (HPTLC). This metagenome extract thin-layer chromatography analysis (META) allows the rapid detection of glycosyltransferase (GT) and also other flavonoid-modifying activities. The developed screening method is highly sensitive, and an amount of 4 ng of modified flavonoid molecules can be detected. This novel technology was validated against a control library of 1,920 fosmid clones generated from a single Bacillus cereus isolate and then used to analyze more than 38,000 clones derived from two different metagenomic preparations. Thereby we identified two novel UDP glycosyltransferase (UGT) genes. The metagenome-derived gtfC gene encoded a 52-kDa protein, and the deduced amino acid sequence was weakly similar to sequences of putative UGTs from Fibrisoma and Dyadobacter. GtfC mediated the transfer of different hexose moieties and exhibited high activities on flavones, flavonols, flavanones, and stilbenes and also accepted isoflavones and chalcones. From the control library we identified a novel macroside glycosyltransferase (MGT) with a calculated molecular mass of 46 kDa. The deduced amino acid sequence was highly similar to sequences of MGTs from Bacillus thuringiensis. Recombinant MgtB transferred the sugar residue from UDP-glucose effectively to flavones, flavonols, isoflavones, and flavanones. Moreover, MgtB exhibited high activity on larger flavonoid molecules such as tiliroside. PMID:23686272

Rabausch, U; Juergensen, J; Ilmberger, N; Böhnke, S; Fischer, S; Schubach, B; Schulte, M; Streit, W R

2013-05-17

231

Antarctic notothenioid fishes: genomic resources and strategies for analyzing an adaptive radiation.  

PubMed

The perciform suborder Notothenoidei provides a compelling opportunity to study the adaptive radiation of a marine species-flock in the cold Southern Ocean that surrounds Antarctica. To facilitate genome-level studies of the diversification of these fishes, we present estimates of the genome sizes of 11 Antarctic species and describe the production of high-quality bacterial artificial chromosome (BAC) libraries for two, the red-blooded notothen Notothenia coriiceps and the white-blooded icefish Chaenocephalus aceratus. Our results indicate that evolution of phylogenetically derived notothenioid families (e.g., the crown group Channichthyidae [icefishes]), was accompanied by genome expansion. Six species from the basal family Nototheniidae had C-values between 0.98 and 1.20?pg, a range that is consistent with the genome sizes of proposed outgroups (e.g., percids) of the notothenioid suborder. In contrast, four icefishes had C-values in the range 1.66-1.83?pg. The BAC libraries VMRC-19 (N. coriiceps) and VMRC-21 (C. aceratus) comprise 12× and 10× coverage of the respective genomes and have average insert sizes of 138 and 168?kb. Paired BAC-end reads representing ?0.1% of each genome showed that the repetitive element landscapes of the two genomes (13.4% of the N. coriiceps genome and 14.5% for C. aceratus) were similar. The availability of these high-quality and well-characterized BAC libraries sets the stage for targeted genomic analyses of the unusual anatomical and physiological adaptations of the notothenioids, some of which mimic human diseases. Here we consider the evolution of secondary pelagicism by various taxa of the group and illustrate the utility of Antarctic icefishes as an evolutionary-mutant model of human osteopenia (low-mineral density of bones). PMID:21082069

Detrich, H W; Amemiya, Chris T

2010-07-12

232

Antarctic Notothenioid Fishes: Genomic Resources and Strategies for Analyzing an Adaptive Radiation  

PubMed Central

The perciform suborder Notothenoidei provides a compelling opportunity to study the adaptive radiation of a marine species-flock in the cold Southern Ocean that surrounds Antarctica. To facilitate genome-level studies of the diversification of these fishes, we present estimates of the genome sizes of 11 Antarctic species and describe the production of high-quality bacterial artificial chromosome (BAC) libraries for two, the red-blooded notothen Notothenia coriiceps and the white-blooded icefish Chaenocephalus aceratus. Our results indicate that evolution of phylogenetically derived notothenioid families (e.g., the crown group Channichthyidae [icefishes]), was accompanied by genome expansion. Six species from the basal family Nototheniidae had C-values between 0.98 and 1.20?pg, a range that is consistent with the genome sizes of proposed outgroups (e.g., percids) of the notothenioid suborder. In contrast, four icefishes had C-values in the range 1.66–1.83?pg. The BAC libraries VMRC-19 (N. coriiceps) and VMRC-21 (C. aceratus) comprise 12× and 10× coverage of the respective genomes and have average insert sizes of 138 and 168?kb. Paired BAC-end reads representing ?0.1% of each genome showed that the repetitive element landscapes of the two genomes (13.4% of the N. coriiceps genome and 14.5% for C. aceratus) were similar. The availability of these high-quality and well-characterized BAC libraries sets the stage for targeted genomic analyses of the unusual anatomical and physiological adaptations of the notothenioids, some of which mimic human diseases. Here we consider the evolution of secondary pelagicism by various taxa of the group and illustrate the utility of Antarctic icefishes as an evolutionary-mutant model of human osteopenia (low-mineral density of bones).

Detrich, H. W.; Amemiya, Chris T.

2010-01-01

233

Construction of a PAC vector system for the propagation of genomic DNA in bacterial and mammalian cells and subsequent generation of nested deletions in individual library members  

Microsoft Academic Search

The BAC and PAC cloning systems allow investigators to propagate large genomic DNA fragments up to 300 kb in size in E. colicells.We describe a new PAC shuttle vector that can be propagated in both bacterial and human cells. Specifically, the P1 cloning vector pAd10sacBII was modified by the insertion of a puromycin-resistance gene (pac), the Epstein-Barr Virus (EBV) latent

Jonathon S Coren; Nat Sternberg

2001-01-01

234

Identification of a new gene encoding 5-enolpyruvylshikimate-3-phosphate synthase using genomic library construction strategy.  

PubMed

Applying the genomic library construction strategy and colony screening, a new aroA gene encoding 5-enolpyruvylshikimate-3-phosphate synthase has been identified, cloned and overexpressed in Escherichia coli, and the enzyme was purified to homogeneity. Kinetic analysis of the AroA( P.fluorescens ) indicated that the full-length enzyme exhibits 10-fold increased IC50 and an approximately 38-fold increased K ( i ) for glyphosate compared to those of the AroA( E.coli ), while retaining high affinity for the substrate phosphoenolpyruvate. Furthermore, we have transformed the new aroA ( P.fluorescens ) gene into Arabidopsis thaliana via a floral dip method, and demonstrated that transgenic A. thaliana plants exhibit significant glyphosate resistance when compared with the wild type. PMID:23090479

Zhou, Chang-Yan; Tian, Yong-Sheng; Xu, Zhi-Sheng; Zhao, Wei; Chen, Chen; Bao, Wen-Hua; Bian, Lin; Cai, Run; Wu, Ai-Zhong

2012-10-23

235

SiRNA sequence model: redesign algorithm based on available genome-wide libraries.  

PubMed

The evolution of RNA interference (RNAi) and the development of technologies exploiting its biology have enabled scientists to rapidly examine the consequences of depleting a particular gene product in cells. Design tools have been developed based on experimental data to increase the knockdown efficiency of siRNAs. Not all siRNAs that are developed to a given target mRNA are equally effective. Currently available design algorithms take an accession, identify conserved regions among their transcript space, find accessible regions within the mRNA, design all possible siRNAs for these regions, filter them based on multi-scores thresholds, and then perform off-target filtration. These different criteria are used by commercial suppliers to produce siRNA genome-wide libraries for different organisms. In this article, we analyze existing siRNA design algorithms and evaluate weight of design parameters for libraries produced in the last decade. We proved that not all essential parameters are currently applied by siRNA vendors. Based on our evaluation results, we were able to suggest an siRNA sequence pattern. The findings in our study can be useful for commercial vendors improving the design of RNAi constructs, by addressing both the issue of potency and the issue of specificity. PMID:23252789

Kozak, Karol

2012-12-20

236

AFLP-derived SCARs facilitate construction of a 1.1 Mb sequence-ready map of a region that spans the Vf locus in the apple genome.  

PubMed

The availability of high-density anchored markers is a prerequisite for reliable construction of a deep coverage BAC contig, which leads to creation of a sequence-ready map in the target chromosomal region. Unfortunately, such markers are not available for most plant species, including woody perennial plants. Here, we report on an efficient approach to build a megabase-size sequence-ready map in the apple genome for the Vf region containing apple scab resistance gene(s) by targeting AFLP-derived SCAR markers to this specific genomic region. A total of 11 AFLP-derived SCAR markers, previously tagged to the Vf locus, along with three other Vf-linked SCAR markers have been used to screen two apple genome BAC libraries. A single BAC contig which spans the Vf region at a physical distance of approximately 1,100 kb has been constructed by assembling the recovered BAC clones, followed by closure of inter-contig gaps. The contig is approximately 4 x deep, and provides a minimal tiling path of 16 contiguous and overlapping BAC clones, thus generating a sequence-ready map. Within the Vf region, duplication events have occurred frequently, and the Vf locus is restricted to the ca. 290 kb region covered by a minimum of three overlapping BAC clones. PMID:12374309

Xu, Mingliang; Korban, Schuyler S

2002-11-01

237

Protective activity of Streptococcus pneumoniae Spr1875 protein fragments identified using a phage displayed genomic library.  

PubMed

There is considerable interest in pneumococcal protein antigens capable of inducing serotype-independent immunoprotection and of improving, thereby, existing vaccines. We report here on the immunogenic properties of a novel surface antigen encoded by ORF spr1875 in the R6 strain genome. An antigenic fragment encoded by spr1875, designated R4, was identified using a Streptococcus pneumoniae phage displayed genomic library after selection with a human convalescent serum. Immunofluorescence analysis with anti-R4 antisera showed that Spr1875 was expressed on the surface of strains belonging to different serotypes. Moreover, the gene was present with little sequence variability in 27 different pneumococcal strains isolated worldwide. A mutant lacking Spr1875 was considerably less virulent than the wild type D39 strain in an intravenous mouse model of infection. Moreover, immunization with the R4 recombinant fragment, but not with the whole Spr1875 protein, induced significant protection against sepsis in mice. Lack of protection after immunization with the whole protein was related to the presence of immunodominant, non-protective epitopes located outside of the R4 fragment. In conclusion, our data indicate that Spr1875 has a role in pneumococcal virulence and is immunogenic. As the R4 fragment conferred immunoprotection from experimental sepsis, selected antigenic fragments of Spr1875 may be useful for the development of a pneumococcal protein-based vaccine. PMID:22570729

Cardaci, Angela; Papasergi, Salvatore; Midiri, Angelina; Mancuso, Giuseppe; Domina, Maria; Cariccio, Veronica Lanza; Mandanici, Francesca; Galbo, Roberta; Lo Passo, Carla; Pernice, Ida; Donato, Paolo; Ricci, Susanna; Biondo, Carmelo; Teti, Giuseppe; Felici, Franco; Beninati, Concetta

2012-05-03

238

Analysis of BAC-end sequences (BESs) and development of BES-SSR markers for genetic mapping and hybrid purity assessment in pigeonpea (Cajanus spp.)  

PubMed Central

Background Pigeonpea [Cajanus cajan (L.) Millsp.] is an important legume crop of rainfed agriculture. Despite of concerted research efforts directed to pigeonpea improvement, stagnated productivity of pigeonpea during last several decades may be accounted to prevalence of various biotic and abiotic constraints and the situation is exacerbated by availability of inadequate genomic resources to undertake any molecular breeding programme for accelerated crop improvement. With the objective of enhancing genomic resources for pigeonpea, this study reports for the first time, large scale development of SSR markers from BAC-end sequences and their subsequent use for genetic mapping and hybridity testing in pigeonpea. Results A set of 88,860 BAC (bacterial artificial chromosome)-end sequences (BESs) were generated after constructing two BAC libraries by using HindIII (34,560 clones) and BamHI (34,560 clones) restriction enzymes. Clustering based on sequence identity of BESs yielded a set of >52K non-redundant sequences, comprising 35 Mbp or >4% of the pigeonpea genome. These sequences were analyzed to develop annotation lists and subdivide the BESs into genome fractions (e.g., genes, retroelements, transpons and non-annotated sequences). Parallel analysis of BESs for microsatellites or simple sequence repeats (SSRs) identified 18,149 SSRs, from which a set of 6,212 SSRs were selected for further analysis. A total of 3,072 novel SSR primer pairs were synthesized and tested for length polymorphism on a set of 22 parental genotypes of 13 mapping populations segregating for traits of interest. In total, we identified 842 polymorphic SSR markers that will have utility in pigeonpea improvement. Based on these markers, the first SSR-based genetic map comprising of 239 loci was developed for this previously uncharacterized genome. Utility of developed SSR markers was also demonstrated by identifying a set of 42 markers each for two hybrids (ICPH 2671 and ICPH 2438) for genetic purity assessment in commercial hybrid breeding programme. Conclusion In summary, while BAC libraries and BESs should be useful for genomics studies, BES-SSR markers, and the genetic map should be very useful for linking the genetic map with a future physical map as well as for molecular breeding in pigeonpea.

2011-01-01

239

NINDS GENSAT BAC Transgenic Project  

NSDL National Science Digital Library

This website from Rockefeller University in New York contains "a gene expression atlas of the central nervous system of the mouse based on bacterial artificial chromosomes (BACs)." GENSAT, or the Gene Expression Nervous System Atlas, contains brain slice images of BAC transgenic mice at the embryonic, postnatal (7 days old), and adult stages, stained to show areas of gene activity. The website comes with a detailed and helpful tutorial that recreates GENSAT's user interface and demonstrates how to manipulate search results.

240

Germ-line transformation of the Queensland fruit fly, Bactrocera tryoni , using a piggyBac vector in the presence of endogenous piggyBac elements  

Microsoft Academic Search

We report the heritable germ-line transformation of the Queensland fruit fly, Bactrocera tryoni, using a piggyBac vector marked with either the fluorescent protein DsRed or EGFP. A transformation frequency of 5–10% was obtained. Inheritance\\u000a of the transgenes has remained stable over more than 15 generations despite the presence of endogenous piggyBac sequences in the B. tryoni genome. The sequence of

K. A. RaphaelD; D. C. A. Shearman; K. Streamer; J. L. Morrow; A. M. Handler; M. Frommer

2011-01-01

241

Identification of piggyBac-mediated insertions in Plasmodium berghei by next generation sequencing  

PubMed Central

Background The piggyBac transposon system provides a powerful forward genetics tool to study gene function in Plasmodium parasites via random insertion mutagenesis and phenotypic screening. The identification of genotype of piggyBac mutants in the Plasmodium genome is thus an indispensable step in forward genetic analysis. Several PCR-based approaches have been used to identify the piggyBac insertion sites in Plasmodium falciparum and Plasmodium berghei, but all are tedious and inefficient. Next generation sequencing can produce large amounts of sequence data and is particularly suitable for genome-wide association studies. In this study, the Next generation sequencing technology was employed to efficiently identify piggyBac insertion sites in the genome of P. berghei. Methods Plasmodium berghei parasites were co-transfected with piggyBac donor and helper plasmids. Initially, the classical inverse PCR method was used to identify the existence of piggyBac insertions in the P. berghei genome. The whole genome of post-transfection parasites was subsequently sequenced with a PCR-free paired-end module using the Illumina HiSeq sequencing system. The two distinct methods (‘BLAST method’ and ‘SOAP method’) were employed to identify piggyBac insertion sites in the P. berghei genome with Illumina sequencing data. All the identified piggyBac insertions were further tested by half-nested PCR. Results The inverse PCR method resulted in a very low yield of ten individual insertions identified. Conversely, 47 piggyBac insertions were identified from about 1 Gb of Illumina sequencing data via the two distinct analysis methods. The majority of identified piggyBac insertions were confirmed by half-nested PCR. In addition, 1,850 single nucleotide polymorphisms were identified through alignment of the Illumina sequencing data of the P. berghei ANKA strain used in this study with the reference genome sequences. Conclusion This study demonstrates that a high-throughput genome sequencing approach is an efficient tool for the identification of piggyBac-mediated insertions in Plasmodium parasites.

2013-01-01

242

Back to BAC: The Use of Infectious Clone Technologies for Viral Mutagenesis  

PubMed Central

Bacterial artificial chromosome (BAC) vectors were first developed to facilitate the propagation and manipulation of large DNA fragments in molecular biology studies for uses such as genome sequencing projects and genetic disease models. To facilitate these studies, methodologies have been developed to introduce specific mutations that can be directly applied to the mutagenesis of infectious clones (icBAC) using BAC technologies. This has resulted in rapid identification of gene function and expression at unprecedented rates. Here we review the major developments in BAC mutagenesis in vitro. This review summarises the technologies used to construct and introduce mutations into herpesvirus icBAC. It also explores developing technologies likely to provide the next leap in understanding these important viruses.

Hall, Robyn N.; Meers, Joanne; Fowler, Elizabeth; Mahony, Timothy

2012-01-01

243

Excision of the piggyBac transposable element in vitro is a precise event that is enhanced by the expression of its encoded transposase  

Microsoft Academic Search

The piggyBac Lepidopteran transposable element moves from the cellular genome into infecting baculovirus genomes during passage of the virus in cultured TN-368 cells. We have constructed genetically tagged piggyBac elements that permit analysis of excision when transiently introduced on plasmids into the piggyBac-deficient Spodoptera frugiperda IPLB-SF21AE cell line. Precise excision of the element from these plasmids occurs at a higher

Teresa A. Elick; Christopher A. Bauser; M. J. Fraser

1996-01-01

244

Construction of Signature-tagged Mutant Library in Mesorhizobium loti as a Powerful Tool for Functional Genomics  

PubMed Central

Rhizobia are nitrogen-fixing soil bacteria that establish endosymbiosis with some leguminous plants. The completion of several rhizobial genome sequences provides opportunities for genome-wide functional studies of the physiological roles of many rhizobial genes. In order to carry out genome-wide phenotypic screenings, we have constructed a large mutant library of the nitrogen-fixing symbiotic bacterium, Mesorhizobium loti, by transposon mutagenesis. Transposon insertion mutants were generated using the signature-tagged mutagenesis (STM) technique and a total of 29 330 independent mutants were obtained. Along with the collection of transposon mutants, we have determined the transposon insertion sites for 7892 clones, and confirmed insertions in 3680 non-redundant M. loti genes (50.5% of the total number of M. loti genes). Transposon insertions were randomly distributed throughout the M. loti genome without any bias toward G+C contents of insertion target sites and transposon plasmids used for the mutagenesis. We also show the utility of STM mutants by examining the specificity of signature tags and test screenings for growth- and nodulation-deficient mutants. This defined mutant library allows for genome-wide forward- and reverse-genetic functional studies of M. loti and will serve as an invaluable resource for researchers to further our understanding of rhizobial biology.

Shimoda, Yoshikazu; Mitsui, Hisayuki; Kamimatsuse, Hiroko; Minamisawa, Kiwamu; Nishiyama, Eri; Ohtsubo, Yoshiyuki; Nagata, Yuji; Tsuda, Masataka; Shinpo, Sayaka; Watanabe, Akiko; Kohara, Mitsuyo; Yamada, Manabu; Nakamura, Yasukazu; Tabata, Satoshi; Sato, Shusei

2008-01-01

245

Genome-wide high-resolution analysis of DNA copy number alterations in NF1-associated malignant peripheral nerve sheath tumors using 32K BAC array.  

PubMed

Neurofibromatosis Type I (NF1) is an autosomal dominant disorder characterized by the development of both benign and malignant tumors. The lifetime risk for developing a malignant peripheral nerve sheath tumor (MPNST) in NF1 patients is approximately 10% with poor survival rates. To date, the molecular basis of MPNST development remains unclear. Here, we report the first genome-wide and high-resolution analysis of DNA copy number alterations in MPNST using the 32K bacterial artificial chromosome microarray on a series of 24 MPNSTs and three neurofibroma samples. In the benign neurofibromas, apart from loss of one copy of the NF1 gene and copy number polymorphisms, no other changes were found. The profiles of malignant samples, however, revealed specific loss of chromosomal regions including 1p35-33, 1p21, 9p21.3, 10q25, 11q22-23, 17q11, and 20p12.2 as well as gain of 1q25, 3p26, 3q13, 5p12, 5q11.2-q14, 5q21-23, 5q31-33, 6p23-p21, 6p12, 6q15, 6q23-q24, 7p22, 7p14-p13, 7q21, 7q36, 8q22-q24, 14q22, and 17q21-q25. Copy number gains were more frequent than deletions in the MPNST samples (62% vs. 38%). The genes resident within common regions of gain were NEDL1 (7p14), AP3B1 (5q14.1), and CUL1 (7q36.1) and these were identified in >63% MPNSTs. The most frequently deleted locus encompassed CDKN2A, CDKN2B, and MTAP genes on 9p21.3 (33% cases). These genes have previously been implicated in other cancer conditions and therefore, should be considered for their therapeutic, prognostic, and diagnostic relevance in NF1 tumorigenesis. PMID:19603524

Mantripragada, Kiran K; Díaz de Stĺhl, Teresita; Patridge, Chris; Menzel, Uwe; Andersson, Robin; Chuzhanova, Nadia; Kluwe, Lan; Guha, Abhijit; Mautner, Victor; Dumanski, Jan P; Upadhyaya, Meena

2009-10-01

246

Phenotypic Screening of Escherichia coli K-12 Tn5 Insertion Libraries, Using Whole-Genome Oligonucleotide Microarrays  

Microsoft Academic Search

Complete genome sequences in combination with global screening methods allow parallel analysis of multiple mutant loci to determine the requirement for specific genes in different environments. In this paper we describe a high-definition microarray approach for investigating the growth effects of Tn5 insertions in Escherichia coli K-12. Libraries of insertion mutants generated by a unique Tn5 mutagenesis system were grown

Kelly M. Winterberg; John Luecke; Amanda S. Bruegl; William S. Reznikoff

2005-01-01

247

Towards a Library of Standard Operating Procedures (SOPs) for (meta)genomic annotation  

SciTech Connect

Genome annotations describe the features of genomes and accompany sequences in genome databases. The methodologies used to generate genome annotation are diverse and typically vary amongst groups. Descriptions of the annotation procedure are helpful in interpreting genome annotation data. Standard Operating Procedures (SOPs) for genome annotation describe the processes that generate genome annotations. Some groups are currently documenting procedures but standards are lacking for structure and content of annotation SOPs. In addition, there is no central repository to store and disseminate procedures and protocols for genome annotation. We highlight the importance of SOPs for genome annotation and endorse a central online repository of SOPs.

Kyrpides, Nikos; Angiuoli, Samuel V.; Cochrane, Guy; Field, Dawn; Garrity, George; Gussman, Aaron; Kodira, Chinnappa D.; Klimke, William; Kyrpides, Nikos; Madupu, Ramana; Markowitz, Victor; Tatusova, Tatiana; Thomson, Nick; White, Owen

2008-04-01

248

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)

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.

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

1998-03-01

249

Construction of a Tn5-tagged mutant library of Xanthomonas oryzae pv. oryzicola as an invaluable resource for functional genomics.  

PubMed

To genome-widely mine pathogenesis-related genes of Xanthomonas oryzae pv. oryzicola (Xoc), which is the casual agent of bacterial leaf streak resulting in significant yield loss and poor quality in rice, a Tn5 transposon-mediated mutation library was generated. Twenty-five thousand transformants were produced by using Tn5 transposome, appropriately corresponding to 5 × ORF coverage of the genome, and inoculated into rice and tobacco, individually and respectively, for screening candidate virulence genes. Southern blot and thermal asymmetric interlaced polymerase chain reaction analysis of Tn5 insertion sites of randomly selected mutants suggested a random mode of transposition and a saturation library. Characterization of extracellular polysaccharides, extracellular protease activity, and pigment production of individual mutants in the growth media revealed that 11 mutants enhanced in growth, 12 reduced extracellular polysaccharide production, 12 lost extracellular protease activity completely or partially, and 21 were pigment deficient. In planta pathogenicity assays revealed 253 mutants reduced virulence in rice, but kept triggering hypersensitive response in tobacco; 49 lost the ability to elicit HR in tobacco and pathogenicity in rice; and 3 still induced hypersensitive response in tobacco, but lost pathogenicity in rice. The achieved mutant library of Xoc is of high-quality and nearly saturated and candidate virulence mutants provided a strong basis for functional genomics of Xoc. PMID:21046389

Zou, Hua-Song; Yuan, Liang; Guo, Wei; Li, Yu-Rong; Che, Yi-Zhou; Zou, Li-Fang; Chen, Gong-You

2010-11-04

250

piggyBac can bypass DNA synthesis during cut and paste transposition  

PubMed Central

DNA synthesis is considered a defining feature in the movement of transposable elements. In determining the mechanism of piggyBac transposition, an insect transposon that is being increasingly used for genome manipulation in a variety of systems including mammalian cells, we have found that DNA synthesis can be avoided during piggyBac transposition, both at the donor site following transposon excision and at the insertion site following transposon integration. We demonstrate that piggyBac transposon excision occurs through the formation of transient hairpins on the transposon ends and that piggyBac target joining occurs by the direct attack of the 3?OH transposon ends on to the target DNA. This is the same strategy for target joining used by the members of DDE superfamily of transposases and retroviral integrases. Analysis of mutant piggyBac transposases in vitro and in vivo using a piggyBac transposition system we have established in Saccharomyces cerevisiae suggests that piggyBac transposase is a member of the DDE superfamily of recombinases, an unanticipated result because of the lack of sequence similarity between piggyBac and DDE family of recombinases.

Mitra, Rupak; Fain-Thornton, Jennifer; Craig, Nancy L

2008-01-01

251

BacT/ALERT BPA Culture Bottle  

Center for Biologics Evaluation and Research (CBER)

... BacT/ALERT BPA Culture Bottle. Applicant: BioMerieux, Inc. 510(k) number: BK050037. Product: BacT/ALERT Culture Bottles. Date: 12/27/2005. -. ... More results from www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts

252

Effects of Blood-Alcohol Concentration (BAC) Feedback on BAC Estimates Over Time  

ERIC Educational Resources Information Center

|This study examines the effects of self-tested blood alcohol concentration (BAC) feedback, from personal hand-held breathalyzers, on the accuracy of BAC estimation. Using an e-mail prompted web-based questionnaire, 19 participants were asked to report both BAC estimates and subsequently measured BAC levels over the course of 27 days. Results from…

Bullers, Susan; Ennis, Melissa

2006-01-01

253

Integrating cytogenetics and genomics in comparative evolutionary studies of cichlid fish  

PubMed Central

Background The availability of a large number of recently sequenced vertebrate genomes opens new avenues to integrate cytogenetics and genomics in comparative and evolutionary studies. Cytogenetic mapping can offer alternative means to identify conserved synteny shared by distinct genomes and also to define genome regions that are still not fine characterized even after wide-ranging nucleotide sequence efforts. An efficient way to perform comparative cytogenetic mapping is based on BAC clones mapping by fluorescence in situ hybridization. In this report, to address the knowledge gap on the genome evolution in cichlid fishes, BAC clones of an Oreochromis niloticus library covering the linkage groups (LG) 1, 3, 5, and 7 were mapped onto the chromosomes of 9 African cichlid species. The cytogenetic mapping data were also integrated with BAC-end sequences information of O. niloticus and comparatively analyzed against the genome of other fish species and vertebrates. Results The location of BACs from LG1, 3, 5, and 7 revealed a strong chromosomal conservation among the analyzed cichlid species genomes, which evidenced a synteny of the markers of each LG. Comparative in silico analysis also identified large genomic blocks that were conserved in distantly related fish groups and also in other vertebrates. Conclusions Although it has been suggested that fishes contain plastic genomes with high rates of chromosomal rearrangements and probably low rates of synteny conservation, our results evidence that large syntenic chromosome segments have been maintained conserved during evolution, at least for the considered markers. Additionally, our current cytogenetic mapping efforts integrated with genomic approaches conduct to a new perspective to address important questions involving chromosome evolution in fishes.

2012-01-01

254

The piggyBac Transposon Displays Local and Distant Reintegration Preferences and Can Cause Mutations at Noncanonical Integration Sites  

PubMed Central

The DNA transposon piggyBac is widely used as a tool in mammalian experimental systems for transgenesis, mutagenesis, and genome engineering. We have characterized genome-wide insertion site preferences of piggyBac by sequencing a large set of integration sites arising from transposition from two separate genomic loci and a plasmid donor in mouse embryonic stem cells. We found that piggyBac preferentially integrates locally to the excision site when mobilized from a chromosomal location and identified other nonlocal regions of the genome with elevated insertion frequencies. piggyBac insertions were associated with expressed genes and markers of open chromatin structure and were excluded from heterochromatin. At the nucleotide level, piggyBac prefers to insert into TA-rich regions within a broader GC-rich context. We also found that piggyBac can insert into sites other than its known TTAA insertion site at a low frequency (2%). Such insertions introduce mismatches that are repaired with signatures of host cell repair pathways. Transposons could be mobilized from plasmids with the observed noncanonical flanking regions, indicating that piggyBac could generate point mutations in the genome.

Li, Meng Amy; Pettitt, Stephen J.; Eckert, Sabine; Ning, Zemin; Rice, Stephen; Cadinanos, Juan; Yusa, Kosuke; Conte, Nathalie

2013-01-01

255

The piggyBac transposon displays local and distant reintegration preferences and can cause mutations at noncanonical integration sites.  

PubMed

The DNA transposon piggyBac is widely used as a tool in mammalian experimental systems for transgenesis, mutagenesis, and genome engineering. We have characterized genome-wide insertion site preferences of piggyBac by sequencing a large set of integration sites arising from transposition from two separate genomic loci and a plasmid donor in mouse embryonic stem cells. We found that piggyBac preferentially integrates locally to the excision site when mobilized from a chromosomal location and identified other nonlocal regions of the genome with elevated insertion frequencies. piggyBac insertions were associated with expressed genes and markers of open chromatin structure and were excluded from heterochromatin. At the nucleotide level, piggyBac prefers to insert into TA-rich regions within a broader GC-rich context. We also found that piggyBac can insert into sites other than its known TTAA insertion site at a low frequency (2%). Such insertions introduce mismatches that are repaired with signatures of host cell repair pathways. Transposons could be mobilized from plasmids with the observed noncanonical flanking regions, indicating that piggyBac could generate point mutations in the genome. PMID:23358416

Li, Meng Amy; Pettitt, Stephen J; Eckert, Sabine; Ning, Zemin; Rice, Stephen; Cadińanos, Juan; Yusa, Kosuke; Conte, Nathalie; Bradley, Allan

2013-01-28

256

Integration of physical and genetic maps in apple confirms whole-genome and segmental duplications in the apple genome.  

PubMed

A total of 355 simple sequence repeat (SSR) markers were developed, based on expressed sequence tag (EST) and bacterial artificial chromosome (BAC)-end sequence databases, and successfully used to construct an SSR-based genetic linkage map of the apple. The consensus linkage map spanned 1143 cM, with an average density of 2.5 cM per marker. Newly developed SSR markers along with 279 SSR markers previously published by the HiDRAS project were further used to integrate physical and genetic maps of the apple using a PCR-based BAC library screening approach. A total of 470 contigs were unambiguously anchored onto all 17 linkage groups of the apple genome, and 158 contigs contained two or more molecular markers. The genetically mapped contigs spanned ?421 Mb in cumulative physical length, representing 60.0% of the genome. The sizes of anchored contigs ranged from 97 kb to 4.0 Mb, with an average of 995 kb. The average physical length of anchored contigs on each linkage group was ?24.8 Mb, ranging from 17.0 Mb to 37.73 Mb. Using BAC DNA as templates, PCR screening of the BAC library amplified fragments of highly homologous sequences from homoeologous chromosomes. Upon integrating physical and genetic maps of the apple, the presence of not only homoeologous chromosome pairs, but also of multiple locus markers mapped to adjacent sites on the same chromosome was detected. These findings demonstrated the presence of both genome-wide and segmental duplications in the apple genome and provided further insights into the complex polyploid ancestral origin of the apple. PMID:21743103

Han, Yuepeng; Zheng, Danman; Vimolmangkang, Sornkanok; Khan, Muhammad A; Beever, Jonathan E; Korban, Schuyler S

2011-07-10

257

Integration of physical and genetic maps in apple confirms whole-genome and segmental duplications in the apple genome  

PubMed Central

A total of 355 simple sequence repeat (SSR) markers were developed, based on expressed sequence tag (EST) and bacterial artificial chromosome (BAC)-end sequence databases, and successfully used to construct an SSR-based genetic linkage map of the apple. The consensus linkage map spanned 1143?cM, with an average density of 2.5?cM per marker. Newly developed SSR markers along with 279 SSR markers previously published by the HiDRAS project were further used to integrate physical and genetic maps of the apple using a PCR-based BAC library screening approach. A total of 470 contigs were unambiguously anchored onto all 17 linkage groups of the apple genome, and 158 contigs contained two or more molecular markers. The genetically mapped contigs spanned ?421?Mb in cumulative physical length, representing 60.0% of the genome. The sizes of anchored contigs ranged from 97?kb to 4.0?Mb, with an average of 995?kb. The average physical length of anchored contigs on each linkage group was ?24.8?Mb, ranging from 17.0?Mb to 37.73?Mb. Using BAC DNA as templates, PCR screening of the BAC library amplified fragments of highly homologous sequences from homoeologous chromosomes. Upon integrating physical and genetic maps of the apple, the presence of not only homoeologous chromosome pairs, but also of multiple locus markers mapped to adjacent sites on the same chromosome was detected. These findings demonstrated the presence of both genome-wide and segmental duplications in the apple genome and provided further insights into the complex polyploid ancestral origin of the apple.

Han, Yuepeng; Zheng, Danman; Vimolmangkang, Sornkanok; Khan, Muhammad A.; Beever, Jonathan E.; Korban, Schuyler S.

2011-01-01

258

A Physical Map of Arabidopsis thaliana Chromosome 3 Represented by Two Contigs of CIC YAC, P1, TAC and BAC Clones  

Microsoft Academic Search

We have constructed a physical map of Arabidopsis thaliana chromosome 3 by ordering the clones from CIC YAC, PI, TAC and BAC libraries using the sequences of a variety of genetic and EST markers and terminal sequences of clones. The markers used were 112 DNA markers, 145 YAC end sequences, and 156 end sequences of PI, TAC and BAC clones.

Shusei SATO; Hirokazu KOTANI; Reiko HAYASHI; Yao-Guang Liu; Daisuke SHIBATA; Satoshi TABATA

1998-01-01

259

Clone libraries and single cell genome amplification reveal extended diversity of uncultivated magnetotactic bacteria from marine and freshwater environments.  

PubMed

Magnetotactic bacteria (MTB), which orient along the earth's magnetic field using magnetosomes, are ubiquitous and abundant in marine and freshwater environments. Previous phylogenetic analysis of diverse MTB has been limited to few cultured species and the most abundant and conspicuous members of natural populations, which were assigned to various lineages of the Proteobacteria, the Nitrospirae phylum as well as the candidate division OP3. However, their known phylogenetic diversity still not matches the large morphological and ultrastructural variability of uncultured MTB found in environmental communities. Here, we used analysis of 16S rRNA gene clone libraries in combination with microsorting and whole-genome amplification to systematically address the entire diversity of uncultured MTB from two different habitats. This approach revealed extensive and novel diversity of MTB within the freshwater and marine sediment samples. In total, single-cell analysis identified eight different phylotypes, which were only partly represented in the clone libraries, and which could be unambiguously assigned to their respective morphotypes. Identified MTB belonged to the Alphaproteobacteria (seven species) and the Nitrospirae phylum (two species). End-sequencing of a small insert library created from WGA-derived DNA of a novel conspicuous magnetotactic vibrio identified genes with highest similarity to two cultivated MTB as well as to other phylogenetic groups. In conclusion, the combination of metagenomic cloning and single cell sorting represents a powerful approach to recover maximum bacterial diversity including low-abundant magnetotactic phylotypes from environmental samples and also provides access to genomic analysis of uncultivated MTB. PMID:23106823

Kolinko, Sebastian; Wanner, Gerhard; Katzmann, Emanuel; Kiemer, Felizitas; M Fuchs, Bernhard; Schüler, Dirk

2012-10-26

260

A rapid method for isolation chromosome band specific cDNAs and genomic cDNAs with microdissection/microcloning libraries  

SciTech Connect

Positional cloning provides a powerful tool for isolation of the gene(s) whose location has been identified while whose biochemical product and function are unknown. Previous techniques for positional cloning require construction of the DNA contig either with YAC, cosmid or bacteriophage clones, which is time consuming. To facilitate this process, we developed a rapid method in which microdissection/microcloning DNA libraries are used as probe pools to directly screen genomic DNA and cDNA libraries. In our initial experiment, we used chromosome band-specific libraries from 5q13 and 2q33 constructed with our microdissection techniques as probe pools to direct screen human genomic library and human brainstem or frontal cortex cDNA libraries using sonicated total human genomic DNA as the competitor. Five genomic DNA clones and 2 cDNA clones have been isolated with the 5q13 library and 11 cDNA clones have been isolated with the 2q33 library. Characterization of 3 genomic and 4 cDNA clones with fluorescence in situ hybridization indicated that these clones are derived from 5q13 and 2q33, respectively. One of our genomic clones had hybridization signals not only at 5q13 but also at 5p13, 5q21 and 5q31, indicating that existence of chromosome-specific repetitive sequences in human chromosome 5. One cDNA clone isolated with 2q33 library contains a polymorphic dinucleotide repeat. Linkage analysis showed that this clone has close linkage with the ALS2 locus previously mapped close to D2S72/D2S116.

He, X.X.; Hentati, A.; Deng, H.X. [Northwestern Univ. Medical School, Chicago, IL (United States)

1994-09-01

261

Integration of the Draft Sequence and Physical Map as a Framework for Genomic Research in Soybean (Glycine max (L.) Merr.) and Wild Soybean (Glycine soja Sieb. and Zucc.)  

PubMed Central

Soybean is a model for the legume research community because of its importance as a crop, densely populated genetic maps, and the availability of a genome sequence. Even though a whole-genome shotgun sequence and bacterial artificial chromosome (BAC) libraries are available, a high-resolution, chromosome-based physical map linked to the sequence assemblies is still needed for whole-genome alignments and to facilitate map-based gene cloning. Three independent G. max BAC libraries combined with genetic and gene-based markers were used to construct a minimum tiling path (MTP) of BAC clones. A total of 107,214 clones were assembled into 1355 FPC (FingerPrinted Contigs) contigs, incorporating 4628 markers and aligned to the G. max reference genome sequence using BAC end-sequence information. Four different MTPs were made for G. max that covered from 92.6% to 95.0% of the soybean draft genome sequence (gmax1.01). Because our purpose was to pick the most reliable and complete MTP, and not the MTP with the minimal number of clones, the FPC map and draft sequence were integrated and clones with unpaired BES were added to build a high-quality physical map with the fewest gaps possible (http://soybase.org). A physical map was also constructed for the undomesticated ancestor (G. soja) of soybean to explore genome variation between G. max and G. soja. 66,028 G. soja clones were assembled into 1053 FPC contigs covering approximately 547 Mbp of the G. max genome sequence. These physical maps for G. max and its undomesticated ancestor, G. soja, will serve as a framework for ordering sequence fragments, comparative genomics, cloning genes, and evolutionary analyses of legume genomes.

Ha, Jungmin; Abernathy, Brian; Nelson, William; Grant, David; Wu, Xiaolei; Nguyen, Henry T.; Stacey, Gary; Yu, Yeisoo; Wing, Rod A.; Shoemaker, Randy C.; Jackson, Scott A.

2012-01-01

262

Isolation ofBrucella abortus ssbanduvrAGenesfroma GenomicLibrary byUseofLymphocytes asProbes  

Microsoft Academic Search

BruceUa abortus proteins fromvirulent S2308expressed froma pBluescript IISK- genomic library stimulated peripheral blood mononuclear (PBM)cell proliferation fromcattle vaccinated withB.abortus S19. Themethoddescribed herepermits arapid anddirected approach toisolate genesencoding antigens ofB. abortus that interact withlymphocytes primed totheliving bacterium. Thesupernatants fromthebacterial host JM109(DE3) werecultured withfreshly isolated bovine PBM cells. A total of300clones wereevaluated. Ten clones wereidentified thatstimulated T-lymphocyte proliferation. Amongthem, oneclone witha2.5-kb insert

YINGXUN ZHU; GARY A. SPLITITER

1993-01-01

263

A Dense Genetic Linkage Map for Common Carp and Its Integration with a BAC-Based Physical Map  

PubMed Central

Background Common carp (Cyprinus carpio) is one of the most important aquaculture species with an annual global production of 3.4 million metric tons. It is also an important ornamental species as well as an important model species for aquaculture research. To improve the economically important traits of this fish, a number of genomic resources and genetic tools have been developed, including several genetic maps and a bacterial artificial chromosome (BAC)-based physical map. However, integrated genetic and physical maps are not available to study quantitative trait loci (QTL) and assist with fine mapping, positional cloning and whole genome sequencing and assembly. The objective of this study was to integrate the currently available BAC-based physical and genetic maps. Results The genetic map was updated with 592 novel markers, including 312 BAC-anchored microsatellites and 130 SNP markers, and contained 1,209 genetic markers on 50 linkage groups, spanning 3,565.9 cM in the common carp genome. An integrated genetic and physical map of the common carp genome was then constructed, which was composed of 463 physical map contigs and 88 single BACs. Combined lengths of the contigs and single BACs covered a physical length of 498.75 Mb, or around 30% of the common carp genome. Comparative analysis between common carp and zebrafish genomes was performed based on the integrated map, providing more insights into the common carp specific whole genome duplication and segmental rearrangements in the genome. Conclusion We integrated a BAC-based physical map to a genetic linkage map of common carp by anchoring BAC-associated genetic markers. The density of the genetic linkage map was significantly increased. The integrated map provides a tool for both genetic and genomic studies of common carp, which will help us to understand the genomic architecture of common carp and facilitate fine mapping and positional cloning of economically important traits for genetic improvement and modification.

Ji, Peifeng; Zhang, Xiaofeng; Zhao, Zixia; Hou, Guangyuan; Huo, Linhe; Liu, Guiming; Li, Chao; Xu, Peng; Sun, Xiaowen

2013-01-01

264

An efficient protocol for VZV BAC-based mutagenesis.  

PubMed

Varicella-zoster virus (VZV) causes both varicella (chicken pox) and herpes zoster (shingles). As a member of the human herpesvirus family, VZV contains a large 125-kb DNA genome, encoding 70 unique open reading frames (ORFs). The genetic study of VZV has been hindered by the large size of viral genome, and thus the functions of the majority of these ORFs remain unclear. Recently, an efficient protocol has been developed based on a luciferase-containing VZV bacteria artificial chromosome (BAC) system to rapidly isolate and study VZV ORF deletion mutants. PMID:20676976

Zhang, Zhen; Huang, Ying; Zhu, Hua

2010-01-01

265

piggyBac-based insertional mutagenesis in Tribolium castaneum using donor/helper hybrids.  

PubMed

We describe an efficient method for generating new piggyBac insertions in the germline of F(1) hybrid Tribolium castaneum derived from crosses between transgenic helper and donor strains. Helper strains carried single Minos elements encoding piggyBac transposase. The donor strain carried a single piggyBac element inserted into an actin gene, expanding the eye-specific, 3xP3-EGFP (enhanced green fluorescent protein) reporter expression domain to include muscle. Remobilization of the donor element is accompanied by loss of muscle fluorescence but retention of eye fluorescence. In a pilot screen, the piggyBac donor was remobilized in 84% of the hybrid crosses, generating hundreds of new lethal, enhancer-trap, semisterile and other insertions. The jumpstarter system described herein makes genome-wide, saturation insertional mutagenesis a realistic goal in this coleopteran species. PMID:17316329

Lorenzen, M D; Kimzey, T; Shippy, T D; Brown, S J; Denell, R E; Beeman, R W

2007-02-16

266

Cytogenetic Analysis of Populus trichocarpa - Ribosomal DNA, Telomere Repeat Sequence, and Marker-selected BACs  

SciTech Connect

The 18S-28S rDNA and 5S rDNA loci in Populus trichocarpa were localized using fluorescent in situ hybridization (FISH). Two 18S-28S rDNA sites and one 5S rDNA site were identified and located at the ends of 3 different chromosomes. FISH signals from the Arabidopsis -type telomere repeat sequence were observed at the distal ends of each chromosome. Six BAC clones selected from 2 linkage groups based on genome sequence assembly (LG-I and LG-VI) were localized on 2 chromosomes, as expected. BACs from LG-I hybridized to the longest chromosome in the complement. All BAC positions were found to be concordant with sequence assembly positions. BAC-FISH will be useful for delineating each of the Populus trichocarpa chromosomes and improving the sequence assembly of this model angiosperm tree species.

Tuskan, Gerald A [ORNL; Gunter, Lee E [ORNL; DiFazio, Stephen P [West Virginia University

2009-01-01

267

Integration of physical and genetic maps of common bean through BAC-derived microsatellite markers  

Microsoft Academic Search

BACKGROUND: Common bean (Phaseolus vulgaris L.) is the most important legume for direct human consumption and the goal of this study was to integrate a recently constructed physical map for the species with a microsatellite based genetic map using a BAC library from the genotype G19833 and the recombinant inbred line population DOR364 × G19833. RESULTS: We searched for simple

Juana M Córdoba; Carolina Chavarro; Jessica A Schlueter; Scott A Jackson; Matthew W Blair

2010-01-01

268

Local assemblies of paired-end reduced representation libraries sequenced with the illumina genome analyzer in maize.  

PubMed

The use of next-generation DNA sequencing technologies has greatly facilitated reference-guided variant detection in complex plant genomes. However, complications may arise when regions adjacent to a read of interest are used for marker assay development, or when reference sequences are incomplete, as short reads alone may not be long enough to ascertain their uniqueness. Here, the possibility of generating longer sequences in discrete regions of the large and complex genome of maize is demonstrated, using a modified version of a paired-end RAD library construction strategy. Reads are generated from DNA fragments first digested with a methylation-sensitive restriction endonuclease, sheared, enriched with biotin and a selective PCR amplification step, and then sequenced at both ends. Sequences are locally assembled into contigs by subgrouping pairs based on the identity of the read anchored by the restriction site. This strategy applied to two maize inbred lines (B14 and B73) generated 183,609 and 129,018 contigs, respectively, out of which at least 76% were >200?bps in length. A subset of putative single nucleotide polymorphisms from contigs aligning to the B73 reference genome with at least one mismatch was resequenced, and 90% of those in B14 were confirmed, indicating that this method is a potent approach for variant detection and marker development in species with complex genomes or lacking extensive reference sequences. PMID:23093955

Deschamps, Stéphane; Nannapaneni, Kishore; Zhang, Yun; Hayes, Kevin

2012-10-09

269

A genome-wide transgenic RNAi library for conditional gene inactivation in Drosophila  

Microsoft Academic Search

Forward genetic screens in model organisms have provided important insights into numerous aspects of development, physiology and pathology. With the availability of complete genome sequences and the introduction of RNA-mediated gene interference (RNAi), systematic reverse genetic screens are now also possible. Until now, such genome-wide RNAi screens have mostly been restricted to cultured cells and ubiquitous gene inactivation in Caenorhabditis

Georg Dietzl; Doris Chen; Frank Schnorrer; Kuan-Chung Su; Yulia Barinova; Michaela Fellner; Beate Gasser; Kaolin Kinsey; Silvia Oppel; Susanne Scheiblauer; Africa Couto; Vincent Marra; Krystyna Keleman; Barry J. Dickson

2007-01-01

270

Post-integration silencing of piggyBac transposable elements in Aedes aegypti.  

PubMed

The piggyBac transposon, originating in the genome of the Lepidoptera Trichoplusia ni, has a broad host range, making it useful for the development of a number of transposon-based functional genomic technologies including gene vectors, enhancer-, gene- and protein-traps. While capable of being used as a vector for the creation of transgenic insects and insect cell lines, piggyBac has very limited mobility once integrated into the genome of the yellow fever mosquito, Aedes aegypti. A transgenic Aedes aegypti cell line (AagPB8) was created containing three integrated piggyBac elements and the remobilization potential of the elements was tested. The integrated piggyBac elements in AagPB8 were transpositionally silent in the presence of functional transposase, which was shown to be capable of catalyzing the movement of plasmid-borne piggyBac elements in the same cells. The structural integrity of one of the integrated elements along with the quality of element-flanking DNA, which is known to influence transposition rates, were tested in D. melanogaster. The element was found to be structurally intact, capable of transposition and excision in the soma and germ-line of Drosophila melanogaster, and in a DNA sequence context highly conducive to element movement in Drosophila melanogaster. These data show that transpositional silencing of integrated piggyBac elements in the genome of Aedes aegypti appears to be a function of higher scale genome organization or perhaps epigenetic factors, and not due to structural defects or suboptimal integration sites. PMID:23861905

Palavesam, Azhahianambi; Esnault, Caroline; O'Brochta, David A

2013-07-04

271

Construction and characterization of a yeast artificial chromosome library containing seven haploid human genome equivalents  

Microsoft Academic Search

Prior to constructing a library of yeast artificial chromosomes (YACs) containing very large human DNA fragments, the authors performed a series of preliminary experiments aimed at developing a suitable protocol. They found an inverse relationship between YAC insert size and transformation efficiency. Evidence of occasional rearrangement within YAC inserts was found resulting in clonally stable internal deletions or clonally unstable

H. M. Albertsen; H. Abderrahim; H. M. Cann; J. Dausset; D. Le Paslier; D. Cohen

1990-01-01

272

Genomic Libraries and a Host Strain Designed for Highly Efficient Two-Hybrid Selection in Yeast  

Microsoft Academic Search

The twehybrid system is a powerful technique for detecting protein-protein interactions that utilizes the well-developed molecular genetics of the yeast Saccharomyces cermisiae. However, the full potential of this technique has not been realized due to limitations imposed by the components available for use in the system. These limitations include unwieldy plasmid vectors, incomplete or poorly designed two- hybrid libraries, and

Philip James; John Halladay; Elizabeth A. Craig

1996-01-01

273

Conserved microstructure of the Brassica B Genome of Brassica nigra in relation to homologous regions of Arabidopsis thaliana, B. rapa and B. oleracea.  

PubMed

BACKGROUND: The Brassica B genome is known to carry several important traits, yet there has been limited analyses of its underlying genome structure, especially in comparison to the closely related A and C genomes. A bacterial artificial chromosome (BAC) library of Brassica nigra was developed and screened with 17 genes from a 222 kb region of A. thaliana that had been well characterised in both the Brassica A and C genomes. RESULTS: Fingerprinting of 483 apparently non-redundant clones defined physical contigs for the corresponding regions in B. nigra. The target region is duplicated in A. thaliana and six homologous contigs were found in B. nigra resulting from the whole genome triplication event shared by the Brassiceae tribe. BACs representative of each region were sequenced to elucidate the level of microscale rearrangements across the Brassica species divide. CONCLUSIONS: Although the B genome species separated from the A/C lineage some 6 Mya, comparisons between the three paleopolyploid Brassica genomes revealed extensive conservation of gene content and sequence identity. The level of fractionation or gene loss varied across genomes and genomic regions; however, the greatest loss of genes was observed to be common to all three genomes. One large-scale chromosomal rearrangement differentiated the B genome suggesting such events could contribute to the lack of recombination observed between B genome species and those of the closely related A/C lineage. PMID:23586706

Navabi, Zahra-Katy; Huebert, Terry; Sharpe, Andrew G; O Neill, Carmel M; Bancroft, Ian; Parkin, Isobel Ap

2013-04-15

274

Conserved microstructure of the Brassica B Genome of Brassica nigra in relation to homologous regions of Arabidopsis thaliana, B. rapa and B. oleracea  

PubMed Central

Background The Brassica B genome is known to carry several important traits, yet there has been limited analyses of its underlying genome structure, especially in comparison to the closely related A and C genomes. A bacterial artificial chromosome (BAC) library of Brassica nigra was developed and screened with 17 genes from a 222 kb region of A. thaliana that had been well characterised in both the Brassica A and C genomes. Results Fingerprinting of 483 apparently non-redundant clones defined physical contigs for the corresponding regions in B. nigra. The target region is duplicated in A. thaliana and six homologous contigs were found in B. nigra resulting from the whole genome triplication event shared by the Brassiceae tribe. BACs representative of each region were sequenced to elucidate the level of microscale rearrangements across the Brassica species divide. Conclusions Although the B genome species separated from the A/C lineage some 6 Mya, comparisons between the three paleopolyploid Brassica genomes revealed extensive conservation of gene content and sequence identity. The level of fractionation or gene loss varied across genomes and genomic regions; however, the greatest loss of genes was observed to be common to all three genomes. One large-scale chromosomal rearrangement differentiated the B genome suggesting such events could contribute to the lack of recombination observed between B genome species and those of the closely related A/C lineage.

2013-01-01

275

KSHV infection of B-cell lymphoma using a modified KSHV BAC36 and coculturing system.  

PubMed

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of two B cell lymphoproliferative diseases, namely primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). KSHV infection of B cell lymphoma in vitro has been a long-standing battle in advancing human KSHV biology. In this study, a modified form of KSHV BAC36 named BAC36A significantly increased the fidelity of gene-targeted site-directed mutagenesis in the KSHV genome. This modification eliminates tedious screening steps required to obtain mutant clones when a KSHV BAC36 reverse genetic system is used. Coculturing B-cell lymphoma BJAB cells with KSHV BAC36A stably transfected 293T cells enabled us to infect BJAB cells with a KSHV virion derived from the KSHV BAC36A. The coculture system produced substantial amounts of KSHV infection to BJAB, meaning that KSHV virions were released from 293T cells and then infected neighboring BJAB cells. Owing to our success with the KSHV BAC36A and coculture system, we propose a new genetic system for the study of KSHV gene expression and regulation in B-cell lymphoma. PMID:22538658

Cho, Hyosun; Kang, Hyojeung

2012-04-27

276

Use of the piggyBac transposon for germ-line transformation of insects.  

PubMed

Germ-line transformation of insects is now possible with four independent transposable element vector systems. Among these, the TTAA-insertion site specific transposon, piggyBac, discovered in Trichoplusia ni, is one of the most widely used. Transformations have been achieved in a wide variety of dipterans, lepidopterans, and a coleopteran, and for many species, piggyBac transposition was first tested by plasmid-based mobility assays in cell lines and embryos. All plasmid and genomic insertions are consistent with the duplication of a TTAA insertion site, and most germ-line integrations appear to be stable, though this is largely based on stable marker phenotypes. Of the vector systems presently in use for non-drosophilids, piggyBac is the only one not currently associated with a superfamily of transposable elements, though other elements exist that share its TTAA insertion site specificity. While functional piggyBac elements have only been isolated from T. ni, nearly identical elements have been discovered in a dipteran species, Bactrocera dorsalis, and closely related elements exist in another moth species, Spodoptera frugiperda. It appears that piggyBac has recently traversed insect orders by horizontal transmission, possibly mediated by a baculovirus or other viral system. This interspecies movement has important implications for the practical use of piggyBac to create transgenic insect strains for field release. PMID:12225912

Handler, Alfred M

2002-10-01

277

Exploiting Chemical Libraries, Structure, and Genomics in the Search for Kinase Inhibitors  

Microsoft Academic Search

Selective protein kinase inhibitors were developed on the basis of the unexpected binding mode of 2,6,9-trisubstituted purines to the adenosine triphosphate-binding site of the human cyclin-dependent kinase 2 (CDK2). By iterating chemical library synthesis and biological screening, potent inhibitors of the human CDK2-cyclin A kinase complex and of Saccharomyces cerevisiae Cdc28p were identified. The structural basis for the binding affinity

David J. Lockhart; Sung-Hou Kim; Laurent Meijer; Sophie LeClerc; Georjana Barnes; David O. Morgan; F. Hernan Espinoza; Soojin Kwon; Andy-Mark W. H. Thunnissen; Lisa Wodicka; Nathanael S. Gray; Peter G. Schultz; Thea C. Norman

1998-01-01

278

Rhipicephalus (Boophilus) microplus strain Deutsch, 5 BAC clone sequencing, including two encoding Cytochrome P450s and one encoding CzEst9 carboxylesterase  

Technology Transfer Automated Retrieval System (TEKTRAN)

The cattle tick, Rhipicephalus (Boophilus) microplus, has a genome over 2.4 times the size of the human genome, and with over 70% of repetitive DNA, this genome would prove very costly to sequence at today's prices and difficult to assemble and analyze. BAC clones give insight into the genome struct...

279

Final report. Human artificial episomal chromosome (HAEC) for building large genomic libraries  

SciTech Connect

Collections of human DNA fragments are maintained for research purposes as clones in bacterial host cells. However for unknown reasons, some regions of the human genome appear to be unclonable or unstable in bacteria. Their team has developed a system using episomes (extrachromosomal, autonomously replication DNA) that maintains large DNA fragments in human cells. This human artificial episomal chromosomal (HAEC) system may prove useful for coverage of these especially difficult regions. In the broader biomedical community, the HAEC system also shows promise for use in functional genomics and gene therapy. Recent improvements to the HAEC system and its application to mapping, sequencing, and functionally studying human and mouse DNA are summarized. Mapping and sequencing the human genome and model organisms are only the first steps in determining the function of various genetic units critical for gene regulation, DNA replication, chromatin packaging, chromosomal stability, and chromatid segregation. Such studies will require the ability to transfer and manipulate entire functional units into mammalian cells.

Jean-Michael H. Vos

1999-12-09

280

piggyBac transposon remobilization and enhancer detection in Anopheles mosquitoes  

PubMed Central

Technical advances in mosquito biology are enabling the development of new approaches to vector control. Absent are powerful forward-genetics technologies, such as enhancer and gene traps, that permit determination of gene functions from the phenotypes arising from transposon insertion mutations. We show that the piggyBac transposon is highly active in the germline of the human malaria vector Anopheles stephensi. Up to 6% of the progeny from transgenic A. stephensi containing a single 6-kb piggyBac element with a marker gene expressing EGFP had the vector in new genomic locations when piggyBac transposase was provided in trans from a second integrated transgene. The active transposition of piggyBac resulted in the efficient detection of enhancers, with ?10% of the progeny with piggyBac in new locations with novel patterns of EGFP expression in third and fourth instar larvae and in adults. The availability of advanced transgenic capabilities such as efficient transposon-based forward-genetics technologies for Anopheles mosquitoes not only will accelerate our understanding of mosquito functional genomics and the development of novel vector and disease transmission control strategies, but also will enable studies by evolutionary developmental biologists, virologists, and parasitologists.

O'Brochta, David A.; Alford, Robert T.; Pilitt, Kristina L.; Aluvihare, Channa U.; Harrell, Robert A.

2011-01-01

281

Sequenced BAC anchored reference genetic map that reconciles the ten individual chromosomes of Brassica rapa  

Microsoft Academic Search

BACKGROUND: In view of the immense value of Brassica rapa in the fields of agriculture and molecular biology, the multinational Brassica rapa Genome Sequencing Project (BrGSP) was launched in 2003 by five countries. The developing BrGSP has valuable resources for the community, including a reference genetic map and seed BAC sequences. Although the initial B. rapa linkage map served as

HyeRan Kim; Su Ryun Choi; Jina Bae; Chang Pyo Hong; Seo Yeon Lee; Dan Van Nguyen; Mina Jin; Beom-Seok Park; Jea-Wook Bang; Ian Bancroft; Yong Pyo Lim

2009-01-01

282

Highly conserved gene order and numerous novel repetitive elements in genomic regions linked to wing pattern variation in Heliconius butterflies  

PubMed Central

Background With over 20 parapatric races differing in their warningly colored wing patterns, the butterfly Heliconius erato provides a fascinating example of an adaptive radiation. Together with matching races of its co-mimic Heliconius melpomene, H. erato also represents a textbook case of Müllerian mimicry, a phenomenon where common warning signals are shared amongst noxious organisms. It is of great interest to identify the specific genes that control the mimetic wing patterns of H. erato and H. melpomene. To this end we have undertaken comparative mapping and targeted genomic sequencing in both species. This paper reports on a comparative analysis of genomic sequences linked to color pattern mimicry genes in Heliconius. Results Scoring AFLP polymorphisms in H. erato broods allowed us to survey loci at approximately 362 kb intervals across the genome. With this strategy we were able to identify markers tightly linked to two color pattern genes: D and Cr, which were then used to screen H. erato BAC libraries in order to identify clones for sequencing. Gene density across 600 kb of BAC sequences appeared relatively low, although the number of predicted open reading frames was typical for an insect. We focused analyses on the D- and Cr-linked H. erato BAC sequences and on the Yb-linked H. melpomene BAC sequence. A comparative analysis between homologous regions of H. erato (Cr-linked BAC) and H. melpomene (Yb-linked BAC) revealed high levels of sequence conservation and microsynteny between the two species. We found that repeated elements constitute 26% and 20% of BAC sequences from H. erato and H. melpomene respectively. The majority of these repetitive sequences appear to be novel, as they showed no significant similarity to any other available insect sequences. We also observed signs of fine scale conservation of gene order between Heliconius and the moth Bombyx mori, suggesting that lepidopteran genome architecture may be conserved over very long evolutionary time scales. Conclusion Here we have demonstrated the tractability of progressing from a genetic linkage map to genomic sequence data in Heliconius butterflies. We have also shown that fine-scale gene order is highly conserved between distantly related Heliconius species, and also between Heliconius and B. mori. Together, these findings suggest that genome structure in macrolepidoptera might be very conserved, and show that mapping and positional cloning efforts in different lepidopteran species can be reciprocally informative.

Papa, Riccardo; Morrison, Clayton M; Walters, James R; Counterman, Brian A; Chen, Rui; Halder, Georg; Ferguson, Laura; Chamberlain, Nicola; ffrench-Constant, Richard; Kapan, Durrell D; Jiggins, Chris D; Reed, Robert D; McMillan, William O

2008-01-01

283

Genomic Sequence around Butterfly Wing Development Genes: Annotation and Comparative Analysis  

PubMed Central

Background Analysis of genomic sequence allows characterization of genome content and organization, and access beyond gene-coding regions for identification of functional elements. BAC libraries, where relatively large genomic regions are made readily available, are especially useful for species without a fully sequenced genome and can increase genomic coverage of phylogenetic and biological diversity. For example, no butterfly genome is yet available despite the unique genetic and biological properties of this group, such as diversified wing color patterns. The evolution and development of these patterns is being studied in a few target species, including Bicyclus anynana, where a whole-genome BAC library allows targeted access to large genomic regions. Methodology/Principal Findings We characterize ?1.3 Mb of genomic sequence around 11 selected genes expressed in B. anynana developing wings. Extensive manual curation of in silico predictions, also making use of a large dataset of expressed genes for this species, identified repetitive elements and protein coding sequence, and highlighted an expansion of Alcohol dehydrogenase genes. Comparative analysis with orthologous regions of the lepidopteran reference genome allowed assessment of conservation of fine-scale synteny (with detection of new inversions and translocations) and of DNA sequence (with detection of high levels of conservation of non-coding regions around some, but not all, developmental genes). Conclusions The general properties and organization of the available B. anynana genomic sequence are similar to the lepidopteran reference, despite the more than 140 MY divergence. Our results lay the groundwork for further studies of new interesting findings in relation to both coding and non-coding sequence: 1) the Alcohol dehydrogenase expansion with higher similarity between the five tandemly-repeated B. anynana paralogs than with the corresponding B. mori orthologs, and 2) the high conservation of non-coding sequence around the genes wingless and Ecdysone receptor, both involved in multiple developmental processes including wing pattern formation.

Conceicao, Ines C.; Long, Anthony D.; Gruber, Jonathan D.; Beldade, Patricia

2011-01-01

284

Introduction of large DNA inserts into the barley pathogenic fungus, Ustilago hordei , via recombined binary BAC vectors and Agrobacterium -mediated transformation  

Microsoft Academic Search

Genetic transformation of organisms with large genome fragments containing complete genes, with regulatory elements or clusters\\u000a of genes, can contribute to the functional analysis of such genes. However, large inserts, such as those found on bacterial\\u000a artificial chromosome (BAC) clones, are often not easy to transfer. We exploited an existing technique to convert BAC clones,\\u000a containing genomic DNA fragments from

Shawkat Ali; Guus Bakkeren

2011-01-01

285

A genomic analysis of Histomonas meleagridis through sequencing of a cDNA library.  

PubMed

Histomonas meleagridis, a flagellated protozoan of the Order Trichomonadida, is the causative agent of blackhead disease in gallinaceous birds. Few genes have been identified in this organism; thus, little is known regarding the molecular basis for its metabolism, virulence, and antigenicity. To identify new genes, a cDNA library derived from a lab strain of H. meleagridis was sequenced and annotated. Data obtained from these experiments identified 3,425 H. meleagridis genes. Analysis of the data allowed the identification of 81 genes coding for putative hydrogenosomal proteins and was used to determine the codon usage frequency. Sequence information also identified bacteria that are cultured with H. meleagridis. Future analysis of these data should provide valuable molecular insights into H. meleagridis and provide the platform for molecular studies aimed at understanding the pathogenesis of blackhead disease. PMID:23075009

Klodnicki, M E; McDougald, L R; Beckstead, R B

2012-10-17

286

Toward forward genetic screens in malaria-causing parasites using the piggyBac transposon  

Microsoft Academic Search

The ability to analyze gene function in malaria-causing Plasmodium parasites has received a boost with a recent paper in BMC Genomics that describes a genome-wide mutagenesis system in the rodent malaria species Plasmodium berghei using the transposon piggyBac. This advance holds promise for identifying and validating new targets for intervention against malaria. But further improvements\\u000a are still needed for the

Brendan S Crabb; Tania F de Koning-Ward; Paul R Gilson

2011-01-01

287

piggyBac transposon system modification of primary human T cells.  

PubMed

The piggyBac transposon system is naturally active, originally derived from the cabbage looper moth. This non-viral system is plasmid based, most commonly utilizing two plasmids with one expressing the piggyBac transposase enzyme and a transposon plasmid harboring the gene(s) of interest between inverted repeat elements which are required for gene transfer activity. PiggyBac mediates gene transfer through a "cut and paste" mechanism whereby the transposase integrates the transposon segment into the genome of the target cell(s) of interest. PiggyBac has demonstrated efficient gene delivery activity in a wide variety of insect, mammalian, and human cells6 including primary human T cells. Recently, a hyperactive piggyBac transposase was generated improving gene transfer efficiency. Human T lymphocytes are of clinical interest for adoptive immunotherapy of cancer. Of note, the first clinical trial involving transposon modification of human T cells using the Sleeping beauty transposon system has been approved. We have previously evaluated the utility of piggyBac as a non-viral methodology for genetic modification of human T cells. We found piggyBac to be efficient in genetic modification of human T cells with a reporter gene and a non-immunogenic inducible suicide gene. Analysis of genomic integration sites revealed a lack of preference for integration into or near known proto-oncogenes. We used piggyBac to gene-modify cytotoxic T lymphocytes to carry a chimeric antigen receptor directed against the tumor antigen HER2, and found that gene-modified T cells mediated targeted killing of HER2-positive tumor cells in vitro and in vivo in an orthotopic mouse model. We have also used piggyBac to generate human T cells resistant to rapamycin, which should be useful in cancer therapies where rapamycin is utilized. Herein, we describe a method for using piggyBac to genetically modify primary human T cells. This includes isolation of peripheral blood mononuclear cells (PBMCs) from human blood followed by culture, gene modification, and activation of T cells. For the purpose of this report, T cells were modified with a reporter gene (eGFP) for analysis and quantification of gene expression by flow cytometry. PiggyBac can be used to modify human T cells with a variety of genes of interest. Although we have used piggyBac to direct T cells to tumor antigens, we have also used piggyBac to add an inducible safety switch in order to eliminate gene modified cells if needed. The large cargo capacity of piggyBac has also enabled gene transfer of a large rapamycin resistant mTOR molecule (15 kb). Therefore, we present a non-viral methodology for stable gene-modification of primary human T cells for a wide variety of purposes. PMID:23149543

Saha, Sunandan; Nakazawa, Yozo; Huye, Leslie E; Doherty, Joseph E; Galvan, Daniel L; Rooney, Cliona M; Wilson, Matthew H

2012-11-05

288

An integrated map of Arabidopsis thaliana for functional analysis of its genome sequence.  

PubMed Central

The genome of the model plant species Arabidopsis thaliana has recently been sequenced. To accelerate its current genome research, we developed a whole-genome, BAC/BIBAC-based, integrated physical, genetic, and sequence map of the A. thaliana ecotype Columbia. This new map was constructed from the clones of a new plant-transformation-competent BIBAC library and is integrated with the existing sequence map. The clones were restriction fingerprinted by DNA sequencing gel-based electrophoresis, assembled into contigs, and anchored to an existing genetic map. The map consists of 194 BAC/BIBAC contigs, spanning 126 Mb of the 130-Mb Arabidopsis genome. A total of 120 contigs, spanning 114 Mb, were anchored to the chromosomes of Arabidopsis. Accuracy of the integrated map was verified using the existing physical and sequence maps and numerous DNA markers. Integration of the new map with the sequence map has enabled gap closure of the sequence map and will facilitate functional analysis of the genome sequence. The method used here has been demonstrated to be sufficient for whole-genome physical mapping from large-insert random bacterial clones and thus is applicable to rapid development of whole-genome physical maps for other species.

Chang, Y L; Tao, Q; Scheuring, C; Ding, K; Meksem, K; Zhang, H B

2001-01-01

289

BacT/ALERT Culture Bottles  

Center for Biologics Evaluation and Research (CBER)

... Applicant: BioMerieux, Inc. 510(k) number: BK000042. Product: BacT/ALERT Culture Bottles. Date: 02/15/2002. -. Supporting Documents. ... More results from www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts

290

BacT/ALERT SA Culture Bottle  

Center for Biologics Evaluation and Research (CBER)

... Resources for You. Cleared 510(k) Submissions with Supporting Documents. -. BacT/ALERT SA Culture Bottle. Applicant: BioMerieux, Inc. ... More results from www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts

291

Advances in BAC-Based Physical Mapping and Map Integration Strategies in Plants  

PubMed Central

In the advent of next-generation sequencing (NGS) platforms, map-based sequencing strategy has been recently suppressed being too expensive and laborious. The detailed studies on NGS drafts alone indicated these assemblies remain far from gold standard reference quality, especially when applied on complex genomes. In this context the conventional BAC-based physical mapping has been identified as an important intermediate layer in current hybrid sequencing strategy. BAC-based physical map construction and its integration with high-density genetic maps have benefited from NGS and high-throughput array platforms. This paper addresses the current advancements of BAC-based physical mapping and high-throughput map integration strategies to obtain densely anchored well-ordered physical maps. The resulted maps are of immediate utility while providing a template to harness the maximum benefits of the current NGS platforms.

Ariyadasa, Ruvini; Stein, Nils

2012-01-01

292

Wheat genomics: present status and future prospects.  

PubMed

Wheat (Triticum aestivum L.), with a large genome (16000 Mb) and high proportion ( approximately 80%) of repetitive sequences, has been a difficult crop for genomics research. However, the availability of extensive cytogenetics stocks has been an asset, which facilitated significant progress in wheat genomic research in recent years. For instance, fairly dense molecular maps (both genetic and physical maps) and a large set of ESTs allowed genome-wide identification of gene-rich and gene-poor regions as well as QTL including eQTL. The availability of markers associated with major economic traits also allowed development of major programs on marker-assisted selection (MAS) in some countries, and facilitated map-based cloning of a number of genes/QTL. Resources for functional genomics including TILLING and RNA interference (RNAi) along with some new approaches like epigenetics and association mapping are also being successfully used for wheat genomics research. BAC/BIBAC libraries for the subgenome D and some individual chromosomes have also been prepared to facilitate sequencing of gene space. In this brief review, we discuss all these advances in some detail, and also describe briefly the available resources, which can be used for future genomics research in this important crop. PMID:18528518

Gupta, P K; Mir, R R; Mohan, A; Kumar, J

2008-01-01

293

Development of a Genomic Microsatellite Library in Perennial Ryegrass (Lolium perenne) and its Use in Trait Mapping  

PubMed Central

Background and Aims Perennial ryegrass (Lolium perenne) is one of the key forage and amenity grasses throughout the world. In the UK it accounts for 70 % of all agricultural land use with an estimated farm gate value of Ł6 billion per annum. However, in terms of the genetic resources available, L. perenne has lagged behind other major crops in Poaceae. The aim of this project was therefore the construction of a microsatellite-enriched genomic library for L. perenne to increase the number of genetic markers available for both marker-assisted selection in breeding programmes and gene isolation. Methods Primers for 229 non-redundant microsatellite markers were designed and used to screen two L. perenne genotypes, one amenity and one forage. Of the 229 microsatellites, 95 were found to show polymorphism between amenity and forage genotypes. A selection of microsatellite primers was selected from these 95 and used to screen two mapping populations derived from intercrossing and backcrossing the two forage and amenity grass genotypes. Key Results and Conclusions The utility of the resulting genetic maps for analysis of the genetic control of target traits was demonstrated by the mapping of genes associated with heading date to linkage groups 4 and 7.

King, J.; Thorogood, D.; Edwards, K. J.; Armstead, I. P.; Roberts, L.; Sk?t, K.; Hanley, Z.; King, I. P.

2008-01-01

294

Targeted isolation, sequence assembly and characterization of two white spruce (Picea glauca) BAC clones for terpenoid synthase and cytochrome P450 genes involved in conifer defence reveal insights into a conifer genome  

Microsoft Academic Search

BACKGROUND: Conifers are a large group of gymnosperm trees which are separated from the angiosperms by more than 300 million years of independent evolution. Conifer genomes are extremely large and contain considerable amounts of repetitive DNA. Currently, conifer sequence resources exist predominantly as expressed sequence tags (ESTs) and full-length (FL)cDNAs. There is no genome sequence available for a conifer or

Björn Hamberger; Dawn Hall; Mack Yuen; Claire Oddy; Britta Hamberger; Christopher I Keeling; Carol Ritland; Kermit Ritland; Jörg Bohlmann

2009-01-01

295

Organization of phenylalanine ammonia lyase ( PAL ), acidic PR5 and osmotin-like ( OSM ) defence-response gene families in the potato genome  

Microsoft Academic Search

Defence-response (DR) genes are candidates for the genetic functions underlying quantitative resistance to plant pathogens.\\u000a The organization of three DR gene families encoding phenylalanine ammonia lyase (PAL), acidic PR-(pathogenesis-related) protein\\u000a 5, and basic PR-5, or osmotin-like (OSM), proteins was studied in the potato genome. A bacterial artificial chromosome (BAC)\\u000a library containing ~50,000 clones was constructed from high-molecular weight genomic DNA

Rosa A. Castillo Ruiz; Carmen Herrera; Marc Ghislain; Christiane Gebhardt

2005-01-01

296

Characterization of the genomic organization of the region bordering the centromere of chromosome V of Podospora anserina by direct sequencing  

Microsoft Academic Search

A Podospora anserina BAC library of 4800 clones has been constructed in the vector pBHYG allowing direct selection in fungi. Screening of the BAC collection for centromeric sequences of chromosome V allowed the recovery of clones localized on either sides of the centromere, but no BAC clone was found to contain the centromere. Seven BAC clones containing 322,195 and 156,244bp

Philippe Silar; Christian Barreau; Robert Debuchy; Sébastien Kicka; Béatrice Turcq; Annie Sainsard-Chanet; Carole H Sellem; Alain Billault; Laurence Cattolico; Simone Duprat; Jean Weissenbach

2003-01-01

297

piggyBac Transposon-Mediated Transgenesis in the Apicomplexan Parasite Eimeria tenella  

PubMed Central

piggyBac, a type II transposon that is useful for efficient transgenesis and insertional mutagenesis, has been used for effective and stable transfection in a wide variety of organisms. In this study we investigate the potential use of the piggyBac transposon system for forward genetics studies in the apicomplexan parasite Eimeria tenella. Using the restriction enzyme-mediated integration (REMI) method, E. tenella sporozoites were electroporated with a donor plasmid containing the enhanced yellow fluorescent protein (EYFP) gene flanked by piggyBac inverted terminal repeats (ITRs), an Asc I-linearized helper plasmid containing the transposase gene and the restriction enzyme Asc I. Subsequently, electroporated sporozoites were inoculated into chickens via the cloacal route and transfected progeny oocysts expressing EYFP were sorted by flow cytometry. A transgenic E. tenella population was selected by successive in vivo passage. Southern-blotting analysis showed that exogenous DNA containing the EYFP gene was integrated into the parasite genome at a limited number of integration sites and that the inserted part of the donor plasmid was the fragment located between the 5? and 3? ITRs as indicated by primer-specific PCR screening. Genome walking revealed that the insertion sites were TTAA-specific, which is consistent with the transposition characteristics of piggyBac.

Su, Huali; Liu, Xianyong; Yan, Wenchao; Shi, Tuanyuan; Zhao, Xinxin; Blake, Damer P.; Tomley, Fiona M.; Suo, Xun

2012-01-01

298

PiggyBac Transposon-Mediated, Reversible Gene Transfer in Human Embryonic Stem Cells  

PubMed Central

Permanent and reversible genetic modifications are important approaches to study gene function in different cell types. They are also important for stem cell researchers to explore and test the therapeutic potential of stem cells. The piggyBac transposon from insects is a rising nonviral system that efficiently mutagenizes and mediates gene transfer into the mammalian genome. It is also characterized by its precise excision, leaving no trace sequence behind so that the genomic integrity of the mutated cell can be restored. Here, we use an optimized piggyBac transposon system to mediate gene transfer and expression of a bifunctional fluorescent reporter in human embryonic stem (ES) cells. We provide molecular evidence for transposase-mediated piggyBac integration events and functional evidence for successful expression of a transferred fluorescent protein genes in human ES cells and their in vitro differentiated derivatives. We also demonstrate that the integrated piggyBac transposon can be removed and an undisrupted insertion site can be restored, which implies potential applications for its use in gene therapy and genetics studies.

Furushima, Kenryo; Hou, Pei-Shan; Ku, Amy T.; Deng, Jian Min; Jang, Chuan-Wei; Fang, Haotian; Adams, Henry P.; Kuo, Min-Liang; Ho, Hong-Nerng

2010-01-01

299

Precise BAC targeting of genetically polymorphic mouse ES cells  

PubMed Central

The use of bacterial artificial chromosomes (BACs) provides a consistent and high targeting efficiency of homologous recombination in embryonic stem (ES) cells, facilitated by long stretches of sequence homology. Here, we introduce a BAC targeting method which employs restriction fragment length polymorphisms (RFLPs) in targeted polymorphic C57BL/6/Cast/Ei F1 mouse ES cell lines to identify properly targeted ES cell clones. We demonstrate that knockout alleles can be generated either by targeting of an RFLP located in the open reading frame thereby disrupting the RFLP and ablating gene function, or by introduction of a transcription stop cassette that prematurely stops transcription of an RFLP located downstream of the stop cassette. With both methods we have generated Rnf12 heterozygous knockout ES cells, which were identified by allele specific PCR using genomic DNA or cDNA as a template. Our results indicate that this novel strategy is efficient and precise, by combining a high targeting efficiency with a convenient PCR based readout and reliable detection of correct targeting events.

Barakat, Tahsin Stefan; Rentmeester, Eveline; Sleutels, Frank; Grootegoed, J. Anton; Gribnau, Joost

2011-01-01

300

Genomic library screening for viruses from the human dental plaque revealed pathogen-specific lytic phage sequences.  

PubMed

Bacterial pathogenesis presents an astounding arsenal of virulence factors that allow them to conquer many different niches throughout the course of infection. Principally fascinating is the fact that some bacterial species are able to induce different diseases by expression of different combinations of virulence factors. Nevertheless, studies aiming at screening for the presence of bacteriophages in humans have been limited. Such screening procedures would eventually lead to identification of phage-encoded properties that impart increased bacterial fitness and/or virulence in a particular niche, and hence, would potentially be used to reverse the course of bacterial infections. As the human oral cavity represents a rich and dynamic ecosystem for several upper respiratory tract pathogens. However, little is known about virus diversity in human dental plaque which is an important reservoir. We applied the culture-independent approach to characterize virus diversity in human dental plaque making a library from a virus DNA fraction amplified using a multiple displacement method and sequenced 80 clones. The resulting sequence showed 44% significant identities to GenBank databases by TBLASTX analysis. TBLAST homology comparisons showed that 66% was viral; 18% eukarya; 10% bacterial; 6% mobile elements. These sequences were sorted into 6 contigs and 45 single sequences in which 4 contigs and a single sequence showed significant identity to a small region of a putative prophage in the Corynebacterium diphtheria genome. These findings interestingly highlight the uniqueness of over half of the sequences, whilst the dominance of a pathogen-specific prophage sequences imply their role in virulence. PMID:21969025

Al-Jarbou, Ahmed Nasser

2011-10-04

301

The effectiveness of reducing illegal blood alcohol concentration (BAC) limits for driving: Evidence for lowering the limit to .05 BAC  

Microsoft Academic Search

PurposeThis scientific review provides a summary of the evidence regarding the benefits of reducing the illegal blood alcohol concentration (BAC) limit for driving and providing a case for enacting a .05 BAC limit.

James C. Fell; Robert B. Voas

2006-01-01

302

Sequenced BAC anchored reference genetic map that reconciles the ten individual chromosomes of Brassica rapa  

PubMed Central

Background In view of the immense value of Brassica rapa in the fields of agriculture and molecular biology, the multinational Brassica rapa Genome Sequencing Project (BrGSP) was launched in 2003 by five countries. The developing BrGSP has valuable resources for the community, including a reference genetic map and seed BAC sequences. Although the initial B. rapa linkage map served as a reference for the BrGSP, there was ambiguity in reconciling the linkage groups with the ten chromosomes of B. rapa. Consequently, the BrGSP assigned each of the linkage groups to the project members as chromosome substitutes for sequencing. Results We identified simple sequence repeat (SSR) motifs in the B. rapa genome with the sequences of seed BACs used for the BrGSP. By testing 749 amplicons containing SSR motifs, we identified polymorphisms that enabled the anchoring of 188 BACs onto the B. rapa reference linkage map consisting of 719 loci in the 10 linkage groups with an average distance of 1.6 cM between adjacent loci. The anchored BAC sequences enabled the identification of 30 blocks of conserved synteny, totaling 534.9 cM in length, between the genomes of B. rapa and Arabidopsis thaliana. Most of these were consistent with previously reported duplication and rearrangement events that differentiate these genomes. However, we were able to identify the collinear regions for seven additional previously uncharacterized sections of the A genome. Integration of the linkage map with the B. rapa cytogenetic map was accomplished by FISH with probes representing 20 BAC clones, along with probes for rDNA and centromeric repeat sequences. This integration enabled unambiguous alignment and orientation of the maps representing the 10 B. rapa chromosomes. Conclusion We developed a second generation reference linkage map for B. rapa, which was aligned unambiguously to the B. rapa cytogenetic map. Furthermore, using our data, we confirmed and extended the comparative genome analysis between B. rapa and A. thaliana. This work will serve as a basis for integrating the genetic, physical, and chromosome maps of the BrGSP, as well as for studies on polyploidization, speciation, and genome duplication in the genus Brassica.

Kim, HyeRan; Choi, Su Ryun; Bae, Jina; Hong, Chang Pyo; Lee, Seo Yeon; Hossain, Md Jamil; Van Nguyen, Dan; Jin, Mina; Park, Beom-Seok; Bang, Jea-Wook; Bancroft, Ian; Lim, Yong Pyo

2009-01-01

303

Important Safety Alert: BacT/ALERT BacT/VIEW Users  

Center for Biologics Evaluation and Research (CBER)

... corruptions can interrupt communication between the BacT/VIEW ® computer and a site's laboratory information management system/laboratory ... More results from www.fda.gov/biologicsbloodvaccines/safetyavailability

304

387. Advantageous Properties of the piggyBac Transposon System for Gene Transfer in Human Cells  

Microsoft Academic Search

Transposon systems permit non-viral delivery of genetic cargo into the genome of human cells and hold promise for eventual use in gene therapy. Transposon systems with activity in vertebrates include Sleeping Beauty (SB) and Mos1 of the Tc1\\/Mariner family and piggyBac which represents a different class of transposable element. We undertook evaluation of these three different transposable elements in human

Matthew H. Wilson; Craig J. Coates; Edward J. Rebar; Alfred L. George

2006-01-01

305

Microsatellite Discovery from BAC End Sequences and Genetic Mapping to Anchor the Soybean Physical and Genetic Maps  

Technology Transfer Automated Retrieval System (TEKTRAN)

Physical maps can be an invaluable resource for improving and assessing the quality of a whole-genome sequence assembly. Here we report the identification and screening of 3,290 microsatellites (SSRs) identified from BAC end sequences of clones comprising the physical map of the cultivar Williams 8...

306

Driver Characteristics and Impairments at Various BACs.  

National Technical Information Service (NTIS)

The purpose of this experiment was to determine (1) the magnitude of alcohol impairment of driving skills as BACs varied from zero to 0.10% and (2) whether age, gender, and drinking practice characteristics of the subjects would differentially affect alco...

H. Moskowitz M. Burns D. Fiorentino A. Smiley P. Zador

2000-01-01

307

Two large-insert soybean genomic libraries constructed in a binary vector: applications in chromosome walking and genome wide physical mapping  

Microsoft Academic Search

Large DNA insert libraries in binary T-DNA vectors can assist in the isolation of the gene(s) underlying a quantitative trait\\u000a locus (QTL). Binary vectors facilitate the transfer of large-insert DNA fragments containing a QTL from E. coli to Agrobacterium sp. and then to plants. We constructed two soybean large-insert libraries from cv. Forrest in the pCLD04541 (V41) binary\\u000a vector after

K. Meksem; K. Zobrist; E. Ruben; D. Hyten; T. Quanzhou; H. B. Zhang; D. A. Lightfoot

2000-01-01

308

PiggyBac Transposon Mutagenesis: A Tool for Cancer Gene Discovery in Mice  

PubMed Central

Transposons are mobile DNA segments that can disrupt gene function by inserting in or near genes. Here we show that insertional mutagenesis by the PiggyBac transposon can be used for cancer gene discovery in mice. PiggyBac transposition in genetically engineered transposon/transposase mice induced cancers whose type (hematopoietic versus solid) and latency were dependent on the regulatory elements introduced into transposons. Analysis of 63 hematopoietic tumors revealed the unique qualities of PiggyBac for genome-wide mutagenesis and discovered many cancer genes not identified in previous retroviral or Sleeping Beauty transposon screens, including Spic, which encodes a PU.1-related transcription factor, and Hdac7, a histone deacetylase gene. PiggyBac and Sleeping Beauty have different integration preferences. To maximize the utility of the tool, we engineered 20 mouse lines to be compatible with both transposases in constitutive, tissue- or temporal-specific mutagenesis. Mice with different transposon types, copy numbers and chromosomal locations support wide applicability.

Rad, Roland; Rad, Lena; Wang, Wei; Cadinanos, Juan; Vassiliou, George; Rice, Stephen; Campos, Lia S.; Yusa, Kosuke; Banerjee, Ruby; Li, Meng Amy; de la Rosa, Jorge; Strong, Alexander; Lu, Dong; Ellis, Peter; Conte, Nathalie; Yang, Fang Tang; Liu, Pentao; Bradley, Allan

2013-01-01

309

DEVELOPMENT OF PCR-BASED MARKERS FROM FIBER ESTS AND BAC-END SEQUENCES FOR THE CONSTRUCTION OF A CONSENSUS COTTON GENETIC MAP.  

Technology Transfer Automated Retrieval System (TEKTRAN)

A new set of molecular markers known as microsatellites or SSRs were developed from cotton fiber genes (EST) and genomic DNA inserted in bacteria artificial chromosomes (BAC-end sequences). Cotton genomics is in its infancy in that a high density PCR-based molecular map to facilitate marker-assisted...

310

Chromosome region-specific libraries for human genome analysis. Progress report, September 1, 1991--August 31, 1992.  

National Technical Information Service (NTIS)

During the grant period progress has been made in the successful demonstration of regional mapping of microclones derived from microdissection libraries; successful demonstration of the feasibility of converting microclones with short inserts into yeast a...

F. T. Kao

1992-01-01

311

BAC-Pool Sequencing and Analysis of Large Segments of A12 and D12 Homoeologous Chromosomes in Upland Cotton  

PubMed Central

Although new and emerging next-generation sequencing (NGS) technologies have reduced sequencing costs significantly, much work remains to implement them for de novo sequencing of complex and highly repetitive genomes such as the tetraploid genome of Upland cotton (Gossypium hirsutum L.). Herein we report the results from implementing a novel, hybrid Sanger/454-based BAC-pool sequencing strategy using minimum tiling path (MTP) BACs from Ctg-3301 and Ctg-465, two large genomic segments in A12 and D12 homoeologous chromosomes (Ctg). To enable generation of longer contig sequences in assembly, we implemented a hybrid assembly method to process ~35x data from 454 technology and 2.8-3x data from Sanger method. Hybrid assemblies offered higher sequence coverage and better sequence assemblies. Homology studies revealed the presence of retrotransposon regions like Copia and Gypsy elements in these contigs and also helped in identifying new genomic SSRs. Unigenes were anchored to the sequences in Ctg-3301 and Ctg-465 to support the physical map. Gene density, gene structure and protein sequence information derived from protein prediction programs were used to obtain the functional annotation of these genes. Comparative analysis of both contigs with Arabidopsis genome exhibited synteny and microcollinearity with a conserved gene order in both genomes. This study provides insight about use of MTP-based BAC-pool sequencing approach for sequencing complex polyploid genomes with limited constraints in generating better sequence assemblies to build reference scaffold sequences. Combining the utilities of MTP-based BAC-pool sequencing with current longer and short read NGS technologies in multiplexed format would provide a new direction to cost-effectively and precisely sequence complex plant genomes.

Buyyarapu, Ramesh; Kantety, Ramesh V.; Yu, John Z.; Xu, Zhanyou; Kohel, Russell J.; Percy, Richard G.; Macmil, Simone; Wiley, Graham B.; Roe, Bruce A.; Sharma, Govind C.

2013-01-01

312

BAC-Pool Sequencing and Analysis of Large Segments of A12 and D12 Homoeologous Chromosomes in Upland Cotton.  

PubMed

Although new and emerging next-generation sequencing (NGS) technologies have reduced sequencing costs significantly, much work remains to implement them for de novo sequencing of complex and highly repetitive genomes such as the tetraploid genome of Upland cotton (Gossypium hirsutum L.). Herein we report the results from implementing a novel, hybrid Sanger/454-based BAC-pool sequencing strategy using minimum tiling path (MTP) BACs from Ctg-3301 and Ctg-465, two large genomic segments in A12 and D12 homoeologous chromosomes (Ctg). To enable generation of longer contig sequences in assembly, we implemented a hybrid assembly method to process ~35x data from 454 technology and 2.8-3x data from Sanger method. Hybrid assemblies offered higher sequence coverage and better sequence assemblies. Homology studies revealed the presence of retrotransposon regions like Copia and Gypsy elements in these contigs and also helped in identifying new genomic SSRs. Unigenes were anchored to the sequences in Ctg-3301 and Ctg-465 to support the physical map. Gene density, gene structure and protein sequence information derived from protein prediction programs were used to obtain the functional annotation of these genes. Comparative analysis of both contigs with Arabidopsis genome exhibited synteny and microcollinearity with a conserved gene order in both genomes. This study provides insight about use of MTP-based BAC-pool sequencing approach for sequencing complex polyploid genomes with limited constraints in generating better sequence assemblies to build reference scaffold sequences. Combining the utilities of MTP-based BAC-pool sequencing with current longer and short read NGS technologies in multiplexed format would provide a new direction to cost-effectively and precisely sequence complex plant genomes. PMID:24116150

Buyyarapu, Ramesh; Kantety, Ramesh V; Yu, John Z; Xu, Zhanyou; Kohel, Russell J; Percy, Richard G; Macmil, Simone; Wiley, Graham B; Roe, Bruce A; Sharma, Govind C

2013-10-08

313

Genomic Analysis of Wild Tomato Introgressions Determining Metabolism- and Yield-Associated Traits1[C][W  

PubMed Central

With the aim of determining the genetic basis of metabolic regulation in tomato fruit, we constructed a detailed physical map of genomic regions spanning previously described metabolic quantitative trait loci of a Solanum pennellii introgression line population. Two genomic libraries from S. pennellii were screened with 104 colocated markers from five selected genomic regions, and a total of 614 bacterial artificial chromosome (BAC)/cosmids were identified as seed clones. Integration of sequence data with the genetic and physical maps of Solanum lycopersicum facilitated the anchoring of 374 of these BAC/cosmid clones. The analysis of this information resulted in a genome-wide map of a nondomesticated plant species and covers 10% of the physical distance of the selected regions corresponding to approximately 1% of the wild tomato genome. Comparative analyses revealed that S. pennellii and domesticated tomato genomes can be considered as largely colinear. A total of 1,238,705 bp from both BAC/cosmid ends and nine large insert clones were sequenced, annotated, and functionally categorized. The sequence data allowed the evaluation of the level of polymorphism between the wild and cultivated tomato species. An exhaustive microsynteny analysis allowed us to estimate the divergence date of S. pennellii and S. lycopersicum at 2.7 million years ago. The combined results serve as a reference for comparative studies both at the macrosyntenic and microsyntenic levels. They also provide a valuable tool for fine-mapping of quantitative trait loci in tomato. Furthermore, they will contribute to a deeper understanding of the regulatory factors underpinning metabolism and hence defining crop chemical composition.

Kamenetzky, Laura; Asis, Ramon; Bassi, Sebastian; de Godoy, Fabiana; Bermudez, Luisa; Fernie, Alisdair R.; Van Sluys, Marie-Anne; Vrebalov, Julia; Giovannoni, James J.; Rossi, Magdalena; Carrari, Fernando

2010-01-01

314

New resources inform study of genome size, content, and organization in nonavian reptiles.  

PubMed

Genomic resources for studies of nonavian reptiles have recently improved and will reach a new level of access once the genomes of the painted turtle (Chrysemys picta) and the green anole (Anolis carolinensis) have been published. Eleven speakers gathered for a symposium on reptilian genomics and evolutionary genetics at the 2008 meeting of the Society for Integrative and Comparative Biology in San Antonio, Texas. Presentations described results of reptilian genetic studies concerning molecular evolution, chromosomal evolution, genomic architecture, population dynamics, endocrinology and endocrine disruption, and the evolution of developmental mechanisms. The presented studies took advantage of the recent generation of genetic and genomic tools and resources. Novel findings demonstrated the positive impact made by the improved availability of resources like genome annotations and bacterial artificial chromosomes (BACs). The symposium was timely and important because it provided a vehicle for the dissemination of novel findings that advance the field. Moreover, this meeting fostered the synergistic interaction of the participants as a group, which is anticipated to encourage the funding and creation of further resources such as additional BAC libraries and genomic projects. Novel data have already been collected and studies like those presented in this symposium promise to shape and improve our understanding of overall amniote evolution. Additional reptilian taxa such as the American alligator (Alligator mississippiensis), tuatara (Sphenodon punctatus), and garter snake (Thamnophis sirtalis) should be the foci of future genomic projects. We hope that the following articles in this volume will help promote these efforts by describing the conclusions and the potential that the improvement of genomic resources for nonavian reptiles can continue having in this important area of integrative and comparative biology. PMID:21669805

Janes, Daniel E; Organ, Christopher; Valenzuela, Nicole

2008-03-16

315

Conserved synteny-based anchoring of the barley genome physical map.  

PubMed

Gene order is largely collinear in the small-grained cereals, a feature which has proved helpful in both marker development and positional cloning. The accuracy of a virtual gene order map ("genome zipper") for barley (Hordeum vulgare), developed by combining a genetic map of this species with a large number of gene locations obtained from the maps constructed in other grass species, was evaluated here both at the genome-wide level and at the fine scale in a representative segment of the genome. Comparing the whole genome "genome zipper" maps with a genetic map developed by using transcript-derived markers, yielded an accuracy of >94 %. The fine-scale comparison involved a 14 cM segment of chromosome arm 2HL. One hundred twenty-eight genes of the "genome zipper" interval were analysed. Over 95 % (45/47) of the polymorphic markers were genetically mapped and allocated to the expected region of 2HL, following the predicted order. A further 80 of the 128 genes were assigned to the correct chromosome arm 2HL by analysis of wheat-barley addition lines. All 128 gene-based markers developed were used to probe a barley bacterial artificial chromosome (BAC) library, delivering 26 BAC contigs from which all except two were anchored to the targeted zipper interval. The results demonstrate that the gene order predicted by the "genome zipper" is remarkably accurate and that the "genome zipper" represents a highly efficient informational resource for the systematic identification of gene-based markers and subsequent physical map anchoring of the barley genome. PMID:23812960

Poursarebani, Naser; Ariyadasa, Ruvini; Zhou, Ruonan; Schulte, Daniela; Steuernagel, Burkhard; Martis, Mihaela Maria; Graner, Andreas; Schweizer, Patrick; Scholz, Uwe; Mayer, Klaus; Stein, Nils

2013-06-28

316

Increased Body Weight of the BAC HD Transgenic Mouse Model of Huntington's Disease Accounts for Some but Not All of the Observed HD-like Motor Deficits  

PubMed Central

The genome of the Bacterial Artificial Chromosome (BAC) transgenic mouse model of Huntington’s Disease (BAC HD) contains the 170 kb human HTT locus modified by the addition of exon 1 with 97 mixed CAA-CAG repeats. BAC HD mice present robust behavioral deficits in both the open field and the accelerating rotarod tests, two standard behavioral assays of motor function. BAC HD mice, however, also typically present significantly increased body weights relative to wildtype littermate controls (WT) which potentially confounds the interpretation of any motor deficits associated directly with the effects of mutant huntingtin. In order to evaluate this possible confound of body weight, we directly compared the performance of BAC HD and WT female mice under food restricted versus free feeding conditions in both the open field and rotarod tasks to test the hypothesis that some of the motor deficits observed in this HTT-transgenic mouse line results solely from increased body weight. Our results suggest that the rotarod deficit exhibited by BAC HD mice is modulated by both body weight and non-body weight factors resulting from overexpression of full length mutant Htt. When body weights of WT and BAC HD transgenic mice were normalized using restricted feeding, the deficits exhibited by BAC HD mice on the rotarod task were less marked, but were still significant. Since the rotarod deficit between WT and BAC HD mice is attenuated when body weight is normalized by food restriction, utilization of this task in BAC HD mice during pre-clinical evaluation must be powered accordingly and results carefully considered as therapeutic benefit can result from decreased overall body weight and or motoric improvement that may not be related to body mass. Furthermore, after controlling for body weight differences, the hypoactive phenotype displayed by ad libitum fed BAC HD mice in the open field assay was not observed in the BAC HD mice undergoing food restriction. These findings suggest that assessment of spontaneous locomotor activity, as measured in the open field test, may not be the appropriate behavioral endpoint to evaluate the BAC HD mouse during preclinical evaluation since it appears that the apparent hypoactive phenotype in this model is driven primarily by body weight differences.

Kudwa, Andrea E.; Menalled, Liliana B.; Oakeshott, Stephen; Murphy, Carol; Mushlin, Richard; Fitzpatrick, John; Miller, Sam F.; McConnell, Kristi; Port, Russell; Torello, Justin; Howland, David; Ramboz, Sylvie; Brunner, Dani

2013-01-01

317

Increased Body Weight of the BAC HD Transgenic Mouse Model of Huntington's Disease Accounts for Some but Not All of the Observed HD-like Motor Deficits.  

PubMed

The genome of the Bacterial Artificial Chromosome (BAC) transgenic mouse model of Huntington's Disease (BAC HD) contains the 170 kb human HTT locus modified by the addition of exon 1 with 97 mixed CAA-CAG repeats. BAC HD mice present robust behavioral deficits in both the open field and the accelerating rotarod tests, two standard behavioral assays of motor function. BAC HD mice, however, also typically present significantly increased body weights relative to wildtype littermate controls (WT) which potentially confounds the interpretation of any motor deficits associated directly with the effects of mutant huntingtin. In order to evaluate this possible confound of body weight, we directly compared the performance of BAC HD and WT female mice under food restricted versus free feeding conditions in both the open field and rotarod tasks to test the hypothesis that some of the motor deficits observed in this HTT-transgenic mouse line results solely from increased body weight. Our results suggest that the rotarod deficit exhibited by BAC HD mice is modulated by both body weight and non-body weight factors resulting from overexpression of full length mutant Htt. When body weights of WT and BAC HD transgenic mice were normalized using restricted feeding, the deficits exhibited by BAC HD mice on the rotarod task were less marked, but were still significant. Since the rotarod deficit between WT and BAC HD mice is attenuated when body weight is normalized by food restriction, utilization of this task in BAC HD mice during pre-clinical evaluation must be powered accordingly and results carefully considered as therapeutic benefit can result from decreased overall body weight and or motoric improvement that may not be related to body mass. Furthermore, after controlling for body weight differences, the hypoactive phenotype displayed by ad libitum fed BAC HD mice in the open field assay was not observed in the BAC HD mice undergoing food restriction. These findings suggest that assessment of spontaneous locomotor activity, as measured in the open field test, may not be the appropriate behavioral endpoint to evaluate the BAC HD mouse during preclinical evaluation since it appears that the apparent hypoactive phenotype in this model is driven primarily by body weight differences. PMID:24042107

Kudwa, Andrea E; Menalled, Liliana B; Oakeshott, Stephen; Murphy, Carol; Mushlin, Richard; Fitzpatrick, John; Miller, Sam F; McConnell, Kristi; Port, Russell; Torello, Justin; Howland, David; Ramboz, Sylvie; Brunner, Dani

2013-07-30

318

The medaka genome: why we need multiple fish models in vertebrate functional genomics.  

PubMed

Medaka (Oryzias latipes) is widely used in research in the fields of biology, medicine, environmental science and fisheries. Zebrafish and medaka are well established as genetic model systems in which large-scale mutagenesis has been successfully performed, and for which EST data, BAC libraries, and fine linkage maps have been accumulated. Among rayfinned fish, there is a large evolutionary distance between medaka and zebrafish. In contrast, the evolutionary distance between medaka and two species of pufferfish, fugu (Takifugu rubripes), and tetraodon (Tetraodon nigroviridis), is almost comparable to that between humans and rodents, and the current genome project is showing that their genome organization is well conserved. Comparison of genome structure among teleosts and mammals helps our understanding of the orthologous gene structure and the evolution of gene families in vertebrates. In addition, gene functions have to be analyzed by both forward and reverse genetics. The Targeting Induced Local Lesions IN Genome (TILLING) system, which includes random mutagenesis, followed by screening for induced mutations in the target genes, is a powerful tool for studying the functional genomics of both medaka and zebrafish. PMID:18753778

Mitani, H; Kamei, Y; Fukamachi, S; Oda, S; Sasaki, T; Asakawa, S; Todo, T; Shimizu, N

2006-01-01

319

Study on control of micro-pollutants by BAC filtration.  

PubMed

The objective of this research was to evaluate removal efficiency of micro-pollutants in a BAC filter that followed ozonation for long term operation. The experimental results showed that after continuous operation for one year BAC filter still maintained a removal of 15 approximately 20% for COD(Mn) and 20 approximately 30% of removal for UV(254). Correlative analysis based on lots of data found that empty bed contact time (EBCT) instead of flow rate could obviously impact on removal effect of micro-pollutants in BAC filter. And the optimal relationship between EBCT and removal effect of micro-pollutants for BAC filter was logarithm. On the other hand, long term running of BAC filter proved that there was a good removal of chloroform formation potential, but the removal of brominated trihalomethane formation potential decline with further bromization, even there appeared to be formation of bromoform in BAC filter. PMID:18725738

Zhang, Z H; Shao, L

2008-01-01

320

Genic regions of a large salamander genome contain long introns and novel genes  

Microsoft Academic Search

BACKGROUND: The basis of genome size variation remains an outstanding question because DNA sequence data are lacking for organisms with large genomes. Sixteen BAC clones from the Mexican axolotl (Ambystoma mexicanum: c-value = 32 × 109 bp) were isolated and sequenced to characterize the structure of genic regions. RESULTS: Annotation of genes within BACs showed that axolotl introns are on

Jeramiah J Smith; Srikrishna Putta; Wei Zhu; Gerald M Pao; Inder M Verma; Tony Hunter; Susan V Bryant; David M Gardiner; Timothy T Harkins; S Randal Voss

2009-01-01

321

Analysis of the Shotgun Expression Library of the Mycobacterium tuberculosis Genome for Immunodominant Polypeptides: Potential Use in Serodiagnosis  

Microsoft Academic Search

A recombinant DNA strategy was applied to analyze and screen the shotgun expression library from a clinically confirmed local virulent isolate of Mycobacterium tuberculosis with sera from tuberculosis patients, which led to expression and purification of highly immunoreactive and specific mycobacterial antigens ex- pressed during the course of active disease which could be of diagnostic significance. An enzyme-linked immunoassay for

Prakash S. Bisen; Sanjay K. Garg; Ram P. Tiwari; P. R. N. Tagore; R. Chandra; R. Karnik; N. Thaker; N. Desai; P. K. Ghosh; M. Fraziano; V. Colizzi

2003-01-01

322

In vivo repackaging of recombinant cosmid molecules for analyses of Salmonella typhimurium, Streptococcus mutans, and mycobacterial genomic libraries.  

PubMed Central

Strains of Escherichia coli K-12 were constructed that permitted the amplification of in vitro-packaged recombinant cosmid-transducing particles by in vivo repackaging of recombinant cosmid molecules. Thermal induction of these thermoinducible, excision-defective lysogens containing recombinant cosmid molecules yielded high titers of packaged recombinant cosmids and low levels of PFU. These strains were used to amplify packaged recombinant cosmid libraries of Mycobacterium leprae, Mycobacterium vaccae, Salmonella typhimurium, and Streptococcus mutans DNA. Contiguous and noncontiguous libraries were compared for the successful identification of cloned genes. Construction of noncontiguous libraries allowed the dissociation of desired genes from genes that were deleterious to the survival of a cosmid recombinant and permitted selection for unlinked traits that resulted in a selected phenotype. In vivo repackaging of recombinant cosmids permitted amplification of the original in vitro-packaged collection of transducing particles, storage of cosmid libraries as phage lysates, facilitation of complementation screening, expression analysis of repackaged recombinant cosmids after UV-irradiated cells were infected, in situ enzyme or immunological screening, and facilitation of recovery of recombinant cosmid molecules containing transposon inserts. Images

Jacobs, W R; Barrett, J F; Clark-Curtiss, J E; Curtiss, R

1986-01-01

323

A Genomic-Scale Artificial MicroRNA Library as a Tool to Investigate the Functionally Redundant Gene Space in Arabidopsis.  

PubMed

Traditional forward genetic screens are limited in the identification of homologous genes with overlapping functions. Here, we report the analyses and assembly of genome-wide protein family definitions that comprise the largest estimate for the potentially redundant gene space in Arabidopsis thaliana. On this basis, a computational design of genome-wide family-specific artificial microRNAs (amiRNAs) was performed using high-performance computing resources. The amiRNA designs are searchable online (http://phantomdb.ucsd.edu). A computationally derived library of 22,000 amiRNAs was synthesized in 10 sublibraries of 1505 to 4082 amiRNAs, each targeting defined functional protein classes. For example, 2964 amiRNAs target annotated DNA and RNA binding protein families and 1777 target transporter proteins, and another sublibrary targets proteins of unknown function. To evaluate the potential of an amiRNA-based screen, we tested 122 amiRNAs targeting transcription factor, protein kinase, and protein phosphatase families. Several amiRNA lines showed morphological phenotypes, either comparable to known phenotypes of single and double/triple mutants or caused by overexpression of microRNAs. Moreover, novel morphological and abscisic acid-insensitive seed germination mutants were identified for amiRNAs targeting zinc finger homeodomain transcription factors and mitogen-activated protein kinase kinase kinases, respectively. These resources provide an approach for genome-wide genetic screens of the functionally redundant gene space in Arabidopsis. PMID:23956262

Hauser, Felix; Chen, Wenxiao; Deinlein, Ulrich; Chang, Kenneth; Ossowski, Stephan; Fitz, Joffrey; Hannon, Gregory J; Schroeder, Julian I

2013-08-16

324

Partial complementation of Sinorhizobium meliloti bacA mutant phenotypes by the Mycobacterium tuberculosis BacA protein.  

PubMed

The Sinorhizobium meliloti BacA ABC transporter protein plays an important role in its nodulating symbiosis with the legume alfalfa (Medicago sativa). The Mycobacterium tuberculosis BacA homolog was found to be important for the maintenance of chronic murine infections, yet its in vivo function is unknown. In the legume plant as well as in the mammalian host, bacteria encounter host antimicrobial peptides (AMPs). We found that the M. tuberculosis BacA protein was able to partially complement the symbiotic defect of an S. meliloti BacA-deficient mutant on alfalfa plants and to protect this mutant in vitro from the antimicrobial activity of a synthetic legume peptide, NCR247, and a recombinant human ?-defensin 2 (HBD2). This finding was also confirmed using an M. tuberculosis insertion mutant. Furthermore, M. tuberculosis BacA-mediated protection of the legume symbiont S. meliloti against legume defensins as well as HBD2 is dependent on its attached ATPase domain. In addition, we show that M. tuberculosis BacA mediates peptide uptake of the truncated bovine AMP, Bac7(1-16). This process required a functional ATPase domain. We therefore suggest that M. tuberculosis BacA is important for the transport of peptides across the cytoplasmic membrane and is part of a complete ABC transporter. Hence, BacA-mediated protection against host AMPs might be important for the maintenance of latent infections. PMID:23161027

Arnold, M F F; Haag, A F; Capewell, S; Boshoff, H I; James, E K; McDonald, R; Mair, I; Mitchell, A M; Kerscher, B; Mitchell, T J; Mergaert, P; Barry, C E; Scocchi, M; Zanda, M; Campopiano, D J; Ferguson, G P

2012-11-16

325

Isolation and characterization of chromosome-specific DNA sequences from a chromosome arm genomic library of common wheat  

Microsoft Academic Search

Summary Isolation, physical mapping and polymorphism of chromo- some-specific DNA sequences in wheat are reported. Following the microdissection of the long arm of chromo- some 5B (5BL) of common wheat, its DNA was amplified by degenerate oligonucleotide-primed PCR and directly cloned into plasmid vectors. Characterization of the chromosome arm library showed that ~55% of the inserts are of low-copy nature.

Bao Liu; Gregorio Segal; Juan Manuel Vega; Moshe Feldman; Shahal Abbo

1997-01-01

326

Matita, a new retroelement from peanut: characterization and evolutionary context in the light of the Arachis A-B genome divergence.  

PubMed

Cultivated peanut is an allotetraploid with an AB-genome. In order to learn more of the genomic structure of peanut, we characterized and studied the evolution of a retrotransposon originally isolated from a resistance gene analog (RGA)-containing bacterial artificial chromosome (BAC) clone. It is a moderate copy number Ty1-copia retrotransposon from the Bianca lineage and we named it Matita. Fluorescent in situ hybridization (FISH) experiments showed that Matita is mainly located on the distal regions of chromosome arms and is of approximately equal frequency on both A- and B-chromosomes. Its chromosome-specific hybridization pattern facilitates the identification of individual chromosomes, a useful cytogenetic tool considering that chromosomes in peanut are mostly metacentric and of similar size. Phylogenetic analysis of Matita elements, molecular dating of transposition events, and an estimation of the evolutionary divergence of the most probable A- and B-donor species suggest that Matita underwent its last major burst of transposition activity at around the same time of the A- and B-genome divergence about 3.5 million years ago. By probing BAC libraries with overgos probes for Matita, resistance gene analogues, and single- or low-copy genes, it was demonstrated that Matita is not randomly distributed in the genome but exhibits a significant tendency of being more abundant near resistance gene homologues than near single-copy genes. The described work is a further step towards broadening the knowledge on genomic and chromosomal structure of peanut and on its evolution. PMID:22120641

Nielen, Stephan; Vidigal, Bruna S; Leal-Bertioli, Soraya C M; Ratnaparkhe, Milind; Paterson, Andrew H; Garsmeur, Olivier; D'Hont, Angélique; Guimarăes, Patricia M; Bertioli, David J

2011-11-27

327

Induction of Specific T-Cell Responses, Opsonizing Antibodies, and Protection against Plasmodium chabaudi adami Infection in Mice Vaccinated with Genomic Expression Libraries Expressed in Targeted and Secretory DNA Vectors  

Microsoft Academic Search

It has been proposed that a multivalent malaria vaccine is necessary to mimic the naturally acquired resistance to this disease observed in humans. A major experimental challenge is to identify the optimal components to be used in such a multivalent vaccine. Expression library immunization (ELI) is a method for screening genomes of a pathogen to identify novel combinations of vaccine

A. Rainczuk; T. Scorza; P. M. Smooker; T. W. Spithill

2003-01-01

328

Polymorphism of the thrombostasin gene in the horn fly (Haematobia irritans) revealed in a cDNA library and in genomic DNA.  

PubMed

Thrombostasin (TS) is a newly described thrombin-inhibiting protein isolated from the saliva of the horn fly (Haematobia irritans), a blood-sucking ectoparasite of cattle. This report provides a detailed characterization of the TS gene and the first analysis of the allelic complexity of a gene for an anti-hemostatic protein from a blood-feeding insect. Multiple point mutations at fixed positions in the TS gene were identified in a cDNA library prepared from mRNA isolated from horn fly salivary glands. When translated, the variant mRNAs would specify five biochemically active peptides that differ in molecular weight, isoelectric point and predicted secondary structure. Allelic variation with the same mutation pattern was revealed in the genomes of individual flies collected in the field and sampled from a long-standing laboratory colony. Approximately 60% of flies examined carried heterozygous alleles, including five additional alleles not found in the cDNA library. Comparative analysis of the allelic mutations and the predicted effects on secondary structures of the active proteins produced suggest that the TS gene may be undergoing evolutionary selection. PMID:11683272

Zhang, D; Cupp, M S; Cupp, E W

2001-10-01

329

New glucosidase activities identified by functional screening of a genomic DNA library from the gut microbiota of the termite Reticulitermes santonensis.  

PubMed

?-Glucosidases are widely distributed in living organisms and play a major role in the degradation of wood, hydrolysing cellobiose or cello-oligosaccharides to glucose. Termites are among the rare animals capable of digesting wood, thanks to enzyme activities of their own and to enzymes produced by their gut microbiota. Many bacteria have been identified in the guts of lower termites, some of which possess cellulolytic or/and hemicellulolytic activity, required for digesting wood. Here, having isolated bacterial colonies from the gut of Reticulitermes santonensis, we constructed in Escherichia coli a genomic DNA library corresponding to all of the colonies obtained and screened the library for clones displaying ?-glucosidase activity. This screen revealed 8 positive clones. Sequence analysis with the BLASTX program revealed putative enzymes belonging to three glycoside hydrolase families (GH1, GH3 and GH4). Agar-plate tests and enzymatic assays revealed differences between the GH1- and GH3-type enzymes (as regards substrate specificity and regulation) and a difference in substrate specificity within the GH3 group. The substrate specificities and characteristic activities of these enzymes suggest that they may intervene in the depolymerisation of cellulose and hemicellulose. PMID:21324659

Mattéotti, Christel; Thonart, Philippe; Francis, Frédéric; Haubruge, Eric; Destain, Jacqueline; Brasseur, Catherine; Bauwens, Julien; De Pauw, Edwin; Portetelle, Daniel; Vandenbol, Micheline

2011-02-16

330

[Construction of the genomic library of Halobacillus sp. D8 and isolation of the glycine betaine transporter betH gene].  

PubMed

Halobacillus sp. D8 is a sporing-forming, gram-positive moderately halophilic bacterium which could tolerate up to 25% (W/V) NaCl. A genomic library of Halobacillus sp. D8 was constructed using pUC18 as vector, and 9000 recombinant plasmids were obtained. By dot blot hybridization, colony PCR and DNA sequencing, the entire glycine betaine transporter betH gene was isolated from the constructed library. Inspection of the sequenced 4.3 kb DNA region revealed the presence of three ORFs. The putative ORF of betH is 1515bp long, encoding a 505-residue protein (BetH) with a calculated molecular mass of 56.1kD. Hydrophobicity plot analysis of BetH indicated a transmembrane protein containing 12 transmembrane regions. Homology searches for BetH of strain D8 in the GenBank using the BLAST program revealed significant sequence identities to other glycine betaine transporters: the putative glycine betaine transporter of O. iheyensis (64% identity), OpuD of B. subtilis (51% identity), BetH of H. trueperi (49% identity), BetL of L. monocytogenes (48% identity), BetM of M. halophilus (43% identity) and the putative glycine betaine transporter of B. halodurans (44% identity). PMID:15989245

Lu, Wei-dong; Zhao, Bai-suo; Feng, De-qin; Wang, Lei; Yang, Su-sheng

2005-06-01

331

Integration of draft sequence and physical map as framework for genomic research in soybean (Glycine max)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three independent BAC libraries, consisting of 223,640 clones, combined with genetic and gene-based markers were used to construct a minimal tiling path (MTP) of BAC clones. Out of the 134,182 fingerprinted clones, 107,214 clones were assembled into contigs and 1,355 FPC contigs were aligned to buil...

332

piggyBac as a high-capacity transgenesis and gene-therapy vector in human cells and mice  

PubMed Central

SUMMARY The stable genomic integration and expression of a large transgene is a major hurdle in gene therapy. We show that the modified piggyBac (PB) transposon system can be used to introduce a 207 kb genomic DNA fragment containing the ROR?/?t locus into human cells and mice. PB-mediated transgenesis results in a single copy of a stably inherited and expressed transgene. These results indicate that PB could serve as an effective high-capacity vector for functional analysis of the mammalian genome and for gene therapy in human cells.

Li, Rongbo; Zhuang, Yuan; Han, Min; Xu, Tian; Wu, Xiaohui

2013-01-01

333

Comparative analysis of acidobacterial genomic fragments from terrestrial and aquatic metagenomic libraries, with emphasis on acidobacteria subdivision 6  

Microsoft Academic Search

The bacterial phylum Acidobacteria has a widespread distribution and is one of the most common and diverse phyla in soil habitats. However, members of this phylum have often been recalcitrant to cultivation methods, hampering the study of this presumably important bacterial group. In this study, we used a cultivation-independent metagenomic approach to recover genomic information from soilborne members of this

A. M. Kielak; J. A. Van Veen; G. A. Kowalchuk

2010-01-01

334

Development of microsatellite markers from an enriched genomic library for genetic analysis of melon (Cucumis melo L.)  

Microsoft Academic Search

BACKGROUND: Despite the great advances in genomic technology observed in several crop species, the availability of molecular tools such as microsatellite markers has been limited in melon (Cucumis melo L.) and cucurbit species. The development of microsatellite markers will have a major impact on genetic analysis and breeding of melon, especially on the generation of marker saturated genetic maps and

Patricia Silva Ritschel; Tulio Cesar de Lima Lins; Rodrigo Lourenço Tristan; Gláucia Salles Cortopassi Buso; José Amauri Buso; Márcio Ferreira

2004-01-01

335

Generation of an inducible and optimized piggyBac transposon system†  

PubMed Central

Genomic studies in the mouse have been slowed by the lack of transposon-mediated mutagenesis. However, since the resurrection of Sleeping Beauty (SB), the possibility of performing forward genetics in mice has been reinforced. Recently, piggyBac (PB), a functional transposon from insects, was also described to work in mammals. As the activity of PB is higher than that of SB11 and SB12, two hyperactive SB transposases, we have characterized and improved the PB system in mouse ES cells. We have generated a mouse codon-optimized version of the PB transposase coding sequence (CDS) which provides transposition levels greater than the original. We have also found that the promoter sequence predicted in the 5?-terminal repeat of the PB transposon is active in the mammalian context. Finally, we have engineered inducible versions of the optimized piggyBac transposase fused with ERT2. One of them, when induced, provides higher levels of transposition than the native piggyBac CDS, whereas in the absence of induction its activity is indistinguishable from background. We expect that these tools, adaptable to perform mouse-germline mutagenesis, will facilitate the identification of genes involved in pathological and physiological processes, such as cancer or ES cell differentiation.

Cadinanos, Juan; Bradley, Allan

2007-01-01

336

Reevaluation of the coding potential and proteomic analysis of the BAC-derived rhesus cytomegalovirus strain 68-1.  

PubMed

Cytomegaloviruses are highly host restricted, resulting in cospeciation with their hosts. As a natural pathogen of rhesus macaques (RM), rhesus cytomegalovirus (RhCMV) has therefore emerged as a highly relevant experimental model for pathogenesis and vaccine development due to its close evolutionary relationship to human CMV (HCMV). Most in vivo experiments performed with RhCMV employed strain 68-1 cloned as a bacterial artificial chromosome (BAC). However, the complete genome sequence of the 68-1 BAC has not been determined. Furthermore, the gene content of the RhCMV genome is unknown, and previous open reading frame (ORF) predictions relied solely on uninterrupted ORFs with an arbitrary cutoff of 300 bp. To obtain a more precise picture of the actual proteins encoded by the most commonly used molecular clone of RhCMV, we reevaluated the RhCMV 68-1 BAC genome by whole-genome shotgun sequencing and determined the protein content of the resulting RhCMV virions by proteomics. By comparing the RhCMV genome to those of several related Old World monkey (OWM) CMVs, we were able to filter out many unlikely ORFs and obtain a simplified map of the RhCMV genome. This comparative genomics analysis suggests a high degree of ORF conservation among OWM CMVs, thus decreasing the likelihood that ORFs found only in RhCMV comprise true genes. Moreover, virion proteomics independently validated the revised ORF predictions, since only proteins that were conserved across OWM CMVs could be detected. Taken together, these data suggest a much higher conservation of genome and virion structure between CMVs of humans, apes, and OWMs than previously assumed. PMID:22718821

Malouli, Daniel; Nakayasu, Ernesto S; Viswanathan, Kasinath; Camp, David G; Chang, W L William; Barry, Peter A; Smith, Richard D; Früh, Klaus

2012-06-20

337

The coxBAC Operon Encodes a Cytochrome c Oxidase Required for Heterotrophic Growth in the Cyanobacterium Anabaena variabilis Strain ATCC 29413  

PubMed Central

Three genes, coxB, coxA, and coxC, found in a clone from a gene library of the cyanobacterium Anabaena variabilis strain ATCC 29413, were identified by hybridization with an oligonucleotide specific for aa3-type cytochrome c oxidases. Deletion of these genes from the genome of A. variabilis strain ATCC 29413 FD yielded strain CSW1, which displayed no chemoheterotrophic growth and an impaired cytochrome c oxidase activity. Photoautotrophic growth of CSW1, however, was unchanged, even with dinitrogen as the nitrogen source. A higher cytochrome c oxidase activity was detected in membrane preparations from dinitrogen-grown CSW1 than from nitrate-grown CSW1, but comparable activities of respiratory oxygen uptake were found in the wild type and in CSW1. Our data indicate that the identified cox gene cluster is essential for fructose-dependent growth in the dark, but not for growth on dinitrogen, and that other terminal respiratory oxidases are expressed in this cyanobacterium. Transcription analysis showed that coxBAC constitutes an operon which is expressed from two transcriptional start points. The use of one of them was stimulated by fructose.

Schmetterer, Georg; Valladares, Ana; Pils, Dietmar; Steinbach, Susanne; Pacher, Margit; Muro-Pastor, Alicia M.; Flores, Enrique; Herrero, Antonia

2001-01-01

338

The coxBAC operon encodes a cytochrome c oxidase required for heterotrophic growth in the cyanobacterium Anabaena variabilis strain ATCC 29413.  

PubMed

Three genes, coxB, coxA, and coxC, found in a clone from a gene library of the cyanobacterium Anabaena variabilis strain ATCC 29413, were identified by hybridization with an oligonucleotide specific for aa(3)-type cytochrome c oxidases. Deletion of these genes from the genome of A. variabilis strain ATCC 29413 FD yielded strain CSW1, which displayed no chemoheterotrophic growth and an impaired cytochrome c oxidase activity. Photoautotrophic growth of CSW1, however, was unchanged, even with dinitrogen as the nitrogen source. A higher cytochrome c oxidase activity was detected in membrane preparations from dinitrogen-grown CSW1 than from nitrate-grown CSW1, but comparable activities of respiratory oxygen uptake were found in the wild type and in CSW1. Our data indicate that the identified cox gene cluster is essential for fructose-dependent growth in the dark, but not for growth on dinitrogen, and that other terminal respiratory oxidases are expressed in this cyanobacterium. Transcription analysis showed that coxBAC constitutes an operon which is expressed from two transcriptional start points. The use of one of them was stimulated by fructose. PMID:11591688

Schmetterer, G; Valladares, A; Pils, D; Steinbach, S; Pacher, M; Muro-Pastor, A M; Flores, E; Herrero, A

2001-11-01

339

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

SciTech Connect

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

Silva, K.F.S.T.

1989-01-01

340

Analysis of the Shotgun Expression Library of the Mycobacterium tuberculosis Genome for Immunodominant Polypeptides: Potential Use in Serodiagnosis  

PubMed Central

A recombinant DNA strategy was applied to analyze and screen the shotgun expression library from a clinically confirmed local virulent isolate of Mycobacterium tuberculosis with sera from tuberculosis patients, which led to expression and purification of highly immunoreactive and specific mycobacterial antigens expressed during the course of active disease which could be of diagnostic significance. An enzyme-linked immunoassay for diagnosis of tuberculosis was devised by using a shotgun immunoexpression library in the ?gt11 vector. DNA from a virulent M. tuberculosis patient isolate (TBW-33) confirmed with the BACTEC 460 system was sheared and expressed to generate shotgun polypeptides. ?-Galactosidase fusion proteins capable of demarcating active tuberculosis infections from Mycobacterium bovis BCG-vaccinated healthy subjects or people harboring environmental mycobacteria were selected by comparative immunoreactivity studies. Promising mycobacterial DNA cassettes were subcloned and expressed into the glutathione S-transferase (GST) fusion vector pGEX-5X-1 with a strong tac promoter and were expressed in Escherichia coli BL21. These fusion proteins were severed at a built-in factor Xa recognition site to separate the GST tags and were utilized in an indirect enzyme-linked immunoassay for serodiagnosis of patients with active tuberculosis. The system offered a clear demarcation between BCG-vaccinated healthy subjects and patients with active tuberculosis and proved to be effective in detecting pulmonary as well as extrapulmonary tuberculosis, with an overall sensitivity of 84.33% and an overall specificity of 93.62%.

Bisen, Prakash S.; Garg, Sanjay K.; Tiwari, Ram P.; Tagore, P. Ravindra Nath; Chandra, Ramesh; Karnik, Rucha; Thaker, Nimesh; Desai, Nirav; Ghosh, P. K.; Fraziano, Maurizio; Colizzi, Vittorio

2003-01-01

341

Factor VIII mRNA expression from a BAC carrying the intact locus made by homologous recombination  

Microsoft Academic Search

Hemophilia A is caused by mutations in the gene encoding factor VIII (F8) and is an important target for gene therapy. The F8 gene contains 26 exons spread over ?186 kb and no work using the intact genomic locus has been carried out. We have constructed a 250-kb BAC carrying all 26 exons, the introns, and more than 40 kb of upstream

Sara Pérez-Luz; Hassan Abdulrazzak; Catherine Grillot-Courvalin; Clare Huxley

2007-01-01

342

Olefin Isomerization Regiochemistries during Tandem Action of BacA and BacB on Prephenate in Bacilysin Biosynthesis†  

PubMed Central

BacA and BacB, the first two enzymes of the bacilysin pathway, convert prephenate to an exocylic regioisomer of dihydrohydroxyphenylpyruvate (ex-H2HPP) on the way to the epoxycyclohexanone warhead in the dipeptide antibiotic, bacilysin. BacA decarboxylates prephenate without aromatization, converting the 1,4-diene in prephenate to the endocyclic 1,3 diene in ?4?8-dihydrohydroxyphenylpyruvate (en-H2HPP). BacB then performs an allylic isomerization to bring the diene into conjugation with the 2-ketone in the product ?3?5-dihydrohydroxyphenylpyruvate (ex-H2HPP). To prove that BacA acts regiospecifically on one of the two prochiral olefins in prephenate, we generated 1,5,8-[13C]-chorismate from bacterial fermentation of 5-[13C]-glucose and in turn produced 2,4,6-[13C]-prephenate via chorismate mutase. Tandem action of BacA and BacB gave 2,4,8-[13C]-7R-ex-H2HPP, showing that BacA isomerizes only the pro-R double bond in prephenate. Nonenzymatic isomerization of the BacA product into conjugation gives only the ?3 E-geometric isomer of ?3?5-ex-H2HPP. On the other hand, acceleration of the allylic isomerization by BacB gives a mixture of the E- and Z-geometric isomers of the 7R-product, indicating some rerouting of the flux, likely through dienolate geometric isomers.

Parker, Jared B.; Walsh, Christopher T.

2012-01-01

343

Olefin isomerization regiochemistries during tandem action of BacA and BacB on prephenate in bacilysin biosynthesis.  

PubMed

BacA and BacB, the first two enzymes of the bacilysin pathway, convert prephenate to an exocylic regioisomer of dihydrohydroxyphenylpyruvate (ex-H(2)HPP) on the way to the epoxycyclohexanone warhead in the dipeptide antibiotic, bacilysin. BacA decarboxylates prephenate without aromatization, converting the 1,4-diene in prephenate to the endocyclic 1,3-diene in ?(4),?(8)-dihydrohydroxyphenylpyruvate (en-H(2)HPP). BacB then performs an allylic isomerization to bring the diene into conjugation with the 2-ketone in the product ?(3),?(5)-dihydrohydroxyphenylpyruvate (ex-H(2)HPP). To prove that BacA acts regiospecifically on one of the two prochiral olefins in prephenate, we generated 1,5,8-[(13)C]-chorismate from bacterial fermentation of 5-[(13)C]-glucose and in turn produced 2,4,6-[(13)C]-prephenate via chorismate mutase. Tandem action of BacA and BacB gave 2,4,8-[(13)C]-7R-ex-H(2)HPP, showing that BacA isomerizes only the pro-R double bond in prephenate. Nonenzymatic isomerization of the BacA product into conjugation gives only the ?(3)E-geometric isomer of ?(3),?(5)-ex-H(2)HPP. On the other hand, acceleration of the allylic isomerization by BacB gives a mixture of the E- and Z-geometric isomers of the 7R- product, indicating some rerouting of the flux, likely through dienolate geometric isomers. PMID:22483065

Parker, Jared B; Walsh, Christopher T

2012-04-06

344

BAC-end sequence-based SNPs and Bin mapping for rapid integration of physical and genetic maps in apple.  

PubMed

A genome-wide BAC physical map of the apple, Malus x domestica Borkh., has been recently developed. Here, we report on integrating the physical and genetic maps of the apple using a SNP-based approach in conjunction with bin mapping. Briefly, BAC clones located at ends of BAC contigs were selected, and sequenced at both ends. The BAC end sequences (BESs) were used to identify candidate SNPs. Subsequently, these candidate SNPs were genetically mapped using a bin mapping strategy for the purpose of mapping the physical onto the genetic map. Using this approach, 52 (23%) out of 228 BESs tested were successfully exploited to develop SNPs. These SNPs anchored 51 contigs, spanning approximately 37 Mb in cumulative physical length, onto 14 linkage groups. The reliability of the integration of the physical and genetic maps using this SNP-based strategy is described, and the results confirm the feasibility of this approach to construct an integrated physical and genetic maps for apple. PMID:19059473

Han, Yuepeng; Chagné, David; Gasic, Ksenija; Rikkerink, Erik H A; Beever, Jonathan E; Gardiner, Susan E; Korban, Schuyler S

2008-12-21

345

Comparative genome analysis of Lactococcus garvieae using a suppression subtractive hybridization library: discovery of novel DNA signatures.  

PubMed

Lactococcus garvieae, the pathogenic species in the genus Lactococcus, is recognized as an emerging pathogen in fish, animals, and humans. Despite the widespread distribution and emerging clinical significance of L. garvieae, little is known about the genomic content of this microorganism. Suppression subtractive hybridization was performed to identify the genomic differences between L. garvieae and Lactococcus lactis ssp. lactis, its closest phylogenetic neighbor, and the type species of the genus Lactococcus. Twenty-seven clones were specific to L. garvieae and were highly different from Lactococcus lactis in their nucleotide and protein sequences. Lactococcus garvieae primer sets were subsequently designed for two of these clones corresponding to a pyrH gene and a novel DNA signature for application in the specific detection of L. garvieae. The primer specificities were evaluated relative to three previously described 16S rRNA gene-targeted methods using 32 Lactococcus and closely related strains. Both newly designed primer sets were highly specific to L. garvieae and performed better than did the existing primers. Our findings may be useful for developing more stable and accurate tools for the discrimination of L. garvieae from other closely related species. PMID:22092865

Kim, Wonyong; Park, Hee Kuk; Thanh, Hien Dang; Lee, Bo-Young; Shin, Jong Wook; Shin, Hyoung-Shik

2011-10-24

346

GENOMIC CHARACTERIZATION AND EXPRESSION ANALYSIS OF THE BACULOVIRAL IAP REPEAT CONTAINING 2 (BIRC2) GENE IN CHANNEL CATFISH, ICTALURUS PUNCTATUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Clones containing the gene for baculoviral IAP repeat containing 2 (BIRC2) were identified by PCR screening of a gynogenetic channel catfish (Ictalurus punctatus) BAC library. Directed sequencing of ~9.5 kb of the BAC clones revealed eight exons and seven introns in the catfish BIRC2 gene. Express...

347

Second-Generation Genetic Linkage Map of Catfish and Its Integration with the BAC-Based Physical Map  

PubMed Central

Construction of high-density genetic linkage maps is crucially important for quantitative trait loci (QTL) studies, and they are more useful when integrated with physical maps. Such integrated maps are valuable genome resources for fine mapping of QTL, comparative genomics, and accurate and efficient whole-genome assembly. Previously, we established both linkage maps and a physical map for channel catfish, Ictalurus punctatus, the dominant aquaculture species in the United States. Here we added 2030 BAC end sequence (BES)-derived microsatellites from 1481 physical map contigs, as well as markers from singleton BES, ESTs, anonymous microsatellites, and SNPs, to construct a second-generation linkage map. Average marker density across the 29 linkage groups reached 1.4 cM/marker. The increased marker density highlighted variations in recombination rates within and among catfish chromosomes. This work effectively anchored 44.8% of the catfish BAC physical map contigs, covering ?52.8% of the genome. The genome size was estimated to be 2546 cM on the linkage map, and the calculated physical distance per centimorgan was 393 Kb. This integrated map should enable comparative studies with teleost model species as well as provide a framework for ordering and assembling whole-genome scaffolds.

Ninwichian, Parichart; Peatman, Eric; Liu, Hong; Kucuktas, Huseyin; Somridhivej, Benjaporn; Liu, Shikai; Li, Ping; Jiang, Yanliang; Sha, Zhenxia; Kaltenboeck, Ludmilla; Abernathy, Jason W.; Wang, Wenqi; Chen, Fei; Lee, Yoona; Wong, Lilian; Wang, Shaolin; Lu, Jianguo; Liu, Zhanjiang

2012-01-01

348

Nucleic acids encoding hyperactive PiggyBac transposases  

US Patent & Trademark Office Database

The present invention provides PiggyBac transposase proteins, nucleic acids encoding the same, compositions comprising the same, kits comprising the same, non-human transgenic animals comprising the same, and methods of using the same.

2013-03-19

349

BacMam recombinant baculoviruses in G protein-coupled receptor drug discovery.  

PubMed

With completion of the sequencing of the human and mouse genomes, the primary sequences of close to 400 non-olfactory G protein-coupled receptors (GPCRs) have been determined. There are intensive efforts within the pharmaceutical industry to discover and develop new therapeutic agents acting via GPCRs. In addition, there is a concerted effort to identify potential new drug targets from the remaining 150+orphan GPCRs through the identification of their ligands. Access to functionally expressed recombinant receptors underpins both of these key drug discovery activities. Typically, GPCR drug discovery screening activities are carried out using mammalian cell lines stably expressing the target of interest. The influx of new receptor sequences originating from genomic sequencing efforts has caused a shift toward wider applications of transient rather than stable expression systems, especially in support of assays for orphan receptor ligand screening. Recombinant baculoviruses in which the polyhedrin promoter has been replaced with a mammalian promoter, termed BacMam viruses, were originally designed as potential new gene therapy delivery vehicles. This same technology offers numerous advantages as a transient expression system in the assay of membrane-expressed drug targets, including GPCRs. Data presented show that BacMam can be used rapidly to generate robust and pharmacologically authentic GPCR assays in several formats, with the potential to transform drug discovery screening processes for this gene family. PMID:15512844

Ames, Robert; Fornwald, James; Nuthulaganti, Parvathi; Trill, John; Foley, James; Buckley, Peter; Kost, Thomas; Wu, Zining; Romanos, Michael

2004-01-01

350

Transcription activator like effector (TALE)-directed piggyBac transposition in human cells.  

PubMed

Insertional therapies have shown great potential for combating genetic disease and safer methods would undoubtedly broaden the variety of possible illness that can be treated. A major challenge that remains is reducing the risk of insertional mutagenesis due to random insertion by both viral and non-viral vectors. Targetable nucleases are capable of inducing double-stranded breaks to enhance homologous recombination for the introduction of transgenes at specific sequences. However, off-target DNA cleavages at unknown sites can lead to mutations that are difficult to detect. Alternatively, the piggyBac transposase is able perform all of the steps required for integration; therefore, cells confirmed to contain a single copy of a targeted transposon, for which its location is known, are likely to be devoid of aberrant genomic modifications. We aimed to retarget transposon insertions by comparing a series of novel hyperactive piggyBac constructs tethered to a custom transcription activator like effector DNA-binding domain designed to bind the first intron of the human CCR5 gene. Multiple targeting strategies were evaluated using combinations of both plasmid-DNA and transposase-protein relocalization to the target sequence. We demonstrated user-defined directed transposition to the CCR5 genomic safe harbor and isolated single-copy clones harboring targeted integrations. PMID:23921635

Owens, Jesse B; Mauro, Damiano; Stoytchev, Ilko; Bhakta, Mital S; Kim, Moon-Soo; Segal, David J; Moisyadi, Stefan

2013-08-05

351

Transcription activator like effector (TALE)-directed piggyBac transposition in human cells  

PubMed Central

Insertional therapies have shown great potential for combating genetic disease and safer methods would undoubtedly broaden the variety of possible illness that can be treated. A major challenge that remains is reducing the risk of insertional mutagenesis due to random insertion by both viral and non-viral vectors. Targetable nucleases are capable of inducing double-stranded breaks to enhance homologous recombination for the introduction of transgenes at specific sequences. However, off-target DNA cleavages at unknown sites can lead to mutations that are difficult to detect. Alternatively, the piggyBac transposase is able perform all of the steps required for integration; therefore, cells confirmed to contain a single copy of a targeted transposon, for which its location is known, are likely to be devoid of aberrant genomic modifications. We aimed to retarget transposon insertions by comparing a series of novel hyperactive piggyBac constructs tethered to a custom transcription activator like effector DNA-binding domain designed to bind the first intron of the human CCR5 gene. Multiple targeting strategies were evaluated using combinations of both plasmid-DNA and transposase-protein relocalization to the target sequence. We demonstrated user-defined directed transposition to the CCR5 genomic safe harbor and isolated single-copy clones harboring targeted integrations.

Owens, Jesse B.; Mauro, Damiano; Stoytchev, Ilko; Bhakta, Mital S.; Kim, Moon-Soo; Segal, David J.; Moisyadi, Stefan

2013-01-01

352

Molecular Cloning and Characterization of a Newly Isolated Pyrethroid-Degrading Esterase Gene from a Genomic Library of Ochrobactrum anthropi YZ-1  

PubMed Central

A novel pyrethroid-degrading esterase gene pytY was isolated from the genomic library of Ochrobactrum anthropi YZ-1. It possesses an open reading frame (ORF) of 897 bp. Blast search showed that its deduced amino acid sequence shares moderate identities (30% to 46%) with most homologous esterases. Phylogenetic analysis revealed that PytY is a member of the esterase VI family. pytY showed very low sequence similarity compared with reported pyrethroid-degrading genes. PytY was expressed, purified, and characterized. Enzyme assay revealed that PytY is a broad-spectrum degrading enzyme that can degrade various pyrethroids. It is a new pyrethroid-degrading gene and enriches genetic resource. Kinetic constants of Km and Vmax were 2.34 mmol·L?1 and 56.33 nmol min?1, respectively, with lambda-cyhalothrin as substrate. PytY displayed good degrading ability and stability over a broad range of temperature and pH. The optimal temperature and pH were of 35°C and 7.5. No cofactors were required for enzyme activity. The results highlighted the potential use of PytY in the elimination of pyrethroid residuals from contaminated environments.

Song, Jinlong; Shi, Yanhua; Li, Kang; Zhao, Bin; Yan, Yanchun

2013-01-01

353

Optimization of the PiggyBac transposon system for the sustained genetic modification of human T lymphocytes.  

PubMed

Optimal implementation of adoptive T-cell therapy for cancer will likely require multiple and maintained genetic modifications of the infused T cells and their progeny so that they home to tumor sites and recognize tumor cells, overcome tumor immune evasion strategies, and remain safe. Retroviral vectors readily transduce T cells and integrate into the host cell genome, but have a limited capacity for multigene insertion and cotransduction and are prohibitively expensive to produce at clinical grade. Genetic modification of T cells using transposons as integrating plasmids is an attractive alternative because of the increased simplicity and cost of production. Of available transposons, piggyBac has the higher transposase activity and larger cargo capacity, and we now evaluate piggyBac for potential adoptive therapies with primary T cells. PiggyBac transposons mediated stable gene expression in approximately 20% of primary T cells without selection. Treatment and maintenance of T cells with interleukin-15 increased stable transgene expression up to approximately 40% and expression was sustained through multiple logs of expansion for over 9 weeks in culture. We demonstrate simultaneous integration of 2 independent transposons in 20% of T cells, a frequency that could be increased to over 85% by selection of a transgenic surface marker (truncated CD19). PiggyBac could also deliver transposons of up to 13 kb with 10,000-fold expansion of transduced T cells in culture and finally we demonstrate delivery of a functional suicide gene (iCasp9). PiggyBac transposons may thus be used to express the multiple integrated transgenes that will likely be necessary for the broader success of T-cell therapy. PMID:19752751

Nakazawa, Yozo; Huye, Leslie E; Dotti, Gianpietro; Foster, Aaron E; Vera, Juan F; Manuri, Pallavi R; June, Carl H; Rooney, Cliona M; Wilson, Matthew H

2009-10-01

354

British Library Newspaper Library  

NSDL National Science Digital Library

The British Library Newspaper Library in Colindale has its catalog of over 50,000 newspaper and periodical title holdings online. Researchers planning a trip to Colindale can now look up titles and dates held in advance. Reservations for materials can even be made by telephone or email. The catalog is searchable by keyword and sorted by title, date, or place. Entries include place, main title, numbers, dates, shelfmark, dates held on microfilm, and other notes. The British Library Newspaper Library's holdings include "all UK national daily and Sunday newspapers from 1801 to the present; most UK and Irish provincial newspapers, some from the early 18th century onwards; [and] selected newspapers from around the world in western and Slavonic languages dating from the 17th century onwards."

2001-01-01

355

A physical map of the highly heterozygous Populus genome: integration with the genome sequence and genetic map  

Microsoft Academic Search

As part of a larger project to sequence the Populus genome and generate genomic resources for this emerging model tree, we constructed a physical map of the Populus genome, representing one of the few such maps of an undomesticated, highly heterozygous plant species. The physical map, consisting of 2802 contigs, was constructed from fingerprinted bacterial artificial chromosome (BAC) clones. The

Colin T. Kelleher; Readman Chiu; Heesun Shin; Martin Krywinski; Martin I. Krzywinski; Jennifer Wilkin; Stephen P. Difazio; Johar Ali; Jennifer K. Asano; Susanna Chan; Alison Cloutier; Noreen Girn; Stephen Leach; Darlene Lee; Carrie A. Mathewson; Teika Olson; Katie OConnor; Anna-Liisa Prabhu; Duane E. Smailus; Jeffery M. Stott; Miranda Tsai; Natasja H. Wye; George S. Yang; Jun Zhuang; Robert A. Holt; Nicholas H. Putnam; Julia Vrebalov; James J. Giovannoni; Jane Grimwood; Jeremy Schmutz; Daniel Rokhsar; Steven J. M. Jones; Marco A. Marra; Gerald A. Tuskan; Jörg Bohlmann; Brian E. Ellis; Kermit Ritland; Carl J. Douglas; Jacqueline E. Schein

2007-01-01

356

Digital Libraries  

NSDL National Science Digital Library

This projects introduces digital libraries, digital initiatives, search techniques, and the Instructional Architect Review Rubric. Digital Library Information : The Scope of the Digital Library D-Lib Journal article, 1998 2008 Joint Conference on Digital Libraries (JCDL) Annual meeting devoted to Digital Libraries Initiatives : Digital Libraries Initiative The Initiative's focus is to dramatically advance the means to collect, store, and organize information in digital forms, and make it available for searching, retrieval, and processing via communication networks -- all in ...

Heather

2008-09-29

357

Pigeonpea genomics initiative (PGI): an international effort to improve crop productivity of pigeonpea (Cajanus cajan L.)  

PubMed Central

Pigeonpea (Cajanus cajan), an important food legume crop in the semi-arid regions of the world and the second most important pulse crop in India, has an average crop productivity of 780 kg/ha. The relatively low crop yields may be attributed to non-availability of improved cultivars, poor crop husbandry and exposure to a number of biotic and abiotic stresses in pigeonpea growing regions. Narrow genetic diversity in cultivated germplasm has further hampered the effective utilization of conventional breeding as well as development and utilization of genomic tools, resulting in pigeonpea being often referred to as an ‘orphan crop legume’. To enable genomics-assisted breeding in this crop, the pigeonpea genomics initiative (PGI) was initiated in late 2006 with funding from Indian Council of Agricultural Research under the umbrella of Indo-US agricultural knowledge initiative, which was further expanded with financial support from the US National Science Foundation’s Plant Genome Research Program and the Generation Challenge Program. As a result of the PGI, the last 3 years have witnessed significant progress in development of both genetic as well as genomic resources in this crop through effective collaborations and coordination of genomics activities across several institutes and countries. For instance, 25 mapping populations segregating for a number of biotic and abiotic stresses have been developed or are under development. An 11X-genome coverage bacterial artificial chromosome (BAC) library comprising of 69,120 clones have been developed of which 50,000 clones were end sequenced to generate 87,590 BAC-end sequences (BESs). About 10,000 expressed sequence tags (ESTs) from Sanger sequencing and ca. 2 million short ESTs by 454/FLX sequencing have been generated. A variety of molecular markers have been developed from BESs, microsatellite or simple sequence repeat (SSR)-enriched libraries and mining of ESTs and genomic amplicon sequencing. Of about 21,000 SSRs identified, 6,698 SSRs are under analysis along with 670 orthologous genes using a GoldenGate SNP (single nucleotide polymorphism) genotyping platform, with large scale SNP discovery using Solexa, a next generation sequencing technology, is in progress. Similarly a diversity array technology array comprising of ca. 15,000 features has been developed. In addition, >600 unique nucleotide binding site (NBS) domain containing members of the NBS-leucine rich repeat disease resistance homologs were cloned in pigeonpea; 960 BACs containing these sequences were identified by filter hybridization, BES physical maps developed using high information content fingerprinting. To enrich the genomic resources further, sequenced soybean genome is being analyzed to establish the anchor points between pigeonpea and soybean genomes. In addition, Solexa sequencing is being used to explore the feasibility of generating whole genome sequence. In summary, the collaborative efforts of several research groups under the umbrella of PGI are making significant progress in improving molecular tools in pigeonpea and should significantly benefit pigeonpea genetics and breeding. As these efforts come to fruition, and expanded (depending on funding), pigeonpea would move from an ‘orphan legume crop’ to one where genomics-assisted breeding approaches for a sustainable crop improvement are routine.

Penmetsa, R. V.; Dutta, S.; Kulwal, P. L.; Saxena, R. K.; Datta, S.; Sharma, T. R.; Rosen, B.; Carrasquilla-Garcia, N.; Farmer, A. D.; Dubey, A.; Saxena, K. B.; Gao, J.; Fakrudin, B.; Singh, M. N.; Singh, B. P.; Wanjari, K. B.; Yuan, M.; Srivastava, R. K.; Kilian, A.; Upadhyaya, H. D.; Mallikarjuna, N.; Town, C. D.; Bruening, G. E.; He, G.; May, G. D.; McCombie, R.; Jackson, S. A.; Singh, N. K.; Cook, D. R.

2009-01-01

358

Novel SSR markers from BAC-end sequences, DArT arrays and a comprehensive genetic map with 1,291 marker loci for chickpea (Cicer arietinum L.).  

PubMed

Chickpea (Cicer arietinum L.) is the third most important cool season food legume, cultivated in arid and semi-arid regions of the world. The goal of this study was to develop novel molecular markers such as microsatellite or simple sequence repeat (SSR) markers from bacterial artificial chromosome (BAC)-end sequences (BESs) and diversity arrays technology (DArT) markers, and to construct a high-density genetic map based on recombinant inbred line (RIL) population ICC 4958 (C. arietinum)×PI 489777 (C. reticulatum). A BAC-library comprising 55,680 clones was constructed and 46,270 BESs were generated. Mining of these BESs provided 6,845 SSRs, and primer pairs were designed for 1,344 SSRs. In parallel, DArT arrays with ca. 15,000 clones were developed, and 5,397 clones were found polymorphic among 94 genotypes tested. Screening of newly developed BES-SSR markers and DArT arrays on the parental genotypes of the RIL mapping population showed polymorphism with 253 BES-SSR markers and 675 DArT markers. Segregation data obtained for these polymorphic markers and 494 markers data compiled from published reports or collaborators were used for constructing the genetic map. As a result, a comprehensive genetic map comprising 1,291 markers on eight linkage groups (LGs) spanning a total of 845.56 cM distance was developed (http://cmap.icrisat.ac.in/cmap/sm/cp/thudi/). The number of markers per linkage group ranged from 68 (LG 8) to 218 (LG 3) with an average inter-marker distance of 0.65 cM. While the developed resource of molecular markers will be useful for genetic diversity, genetic mapping and molecular breeding applications, the comprehensive genetic map with integrated BES-SSR markers will facilitate its anchoring to the physical map (under construction) to accelerate map-based cloning of genes in chickpea and comparative genome evolution studies in legumes. PMID:22102885

Thudi, Mahendar; Bohra, Abhishek; Nayak, Spurthi N; Varghese, Nicy; Shah, Trushar M; Penmetsa, R Varma; Thirunavukkarasu, Nepolean; Gudipati, Srivani; Gaur, Pooran M; Kulwal, Pawan L; Upadhyaya, Hari D; Kavikishor, Polavarapu B; Winter, Peter; Kahl, Günter; Town, Christopher D; Kilian, Andrzej; Cook, Douglas R; Varshney, Rajeev K

2011-11-15

359

Novel SSR Markers from BAC-End Sequences, DArT Arrays and a Comprehensive Genetic Map with 1,291 Marker Loci for Chickpea (Cicer arietinum L.)  

PubMed Central

Chickpea (Cicer arietinum L.) is the third most important cool season food legume, cultivated in arid and semi-arid regions of the world. The goal of this study was to develop novel molecular markers such as microsatellite or simple sequence repeat (SSR) markers from bacterial artificial chromosome (BAC)-end sequences (BESs) and diversity arrays technology (DArT) markers, and to construct a high-density genetic map based on recombinant inbred line (RIL) population ICC 4958 (C. arietinum)×PI 489777 (C. reticulatum). A BAC-library comprising 55,680 clones was constructed and 46,270 BESs were generated. Mining of these BESs provided 6,845 SSRs, and primer pairs were designed for 1,344 SSRs. In parallel, DArT arrays with ca. 15,000 clones were developed, and 5,397 clones were found polymorphic among 94 genotypes tested. Screening of newly developed BES-SSR markers and DArT arrays on the parental genotypes of the RIL mapping population showed polymorphism with 253 BES-SSR markers and 675 DArT markers. Segregation data obtained for these polymorphic markers and 494 markers data compiled from published reports or collaborators were used for constructing the genetic map. As a result, a comprehensive genetic map comprising 1,291 markers on eight linkage groups (LGs) spanning a total of 845.56 cM distance was developed (http://cmap.icrisat.ac.in/cmap/sm/cp/thudi/). The number of markers per linkage group ranged from 68 (LG 8) to 218 (LG 3) with an average inter-marker distance of 0.65 cM. While the developed resource of molecular markers will be useful for genetic diversity, genetic mapping and molecular breeding applications, the comprehensive genetic map with integrated BES-SSR markers will facilitate its anchoring to the physical map (under construction) to accelerate map-based cloning of genes in chickpea and comparative genome evolution studies in legumes.

Nayak, Spurthi N.; Varghese, Nicy; Shah, Trushar M.; Penmetsa, R. Varma; Thirunavukkarasu, Nepolean; Gudipati, Srivani; Gaur, Pooran M.; Kulwal, Pawan L.; Upadhyaya, Hari D.; KaviKishor, Polavarapu B.; Winter, Peter; Kahl, Gunter; Town, Christopher D.; Kilian, Andrzej; Cook, Douglas R.; Varshney, Rajeev K.

2011-01-01

360

Cyclic AMP Effectors in African Trypanosomes Revealed by Genome-Scale RNA Interference Library Screening for Resistance to the Phosphodiesterase Inhibitor CpdA.  

PubMed

One of the most promising new targets for trypanocidal drugs to emerge in recent years is the cyclic AMP (cAMP) phosphodiesterase (PDE) activity encoded by TbrPDEB1 and TbrPDEB2. These genes were genetically confirmed as essential, and a high-affinity inhibitor, CpdA, displays potent antitrypanosomal activity. To identify effectors of the elevated cAMP levels resulting from CpdA action and, consequently, potential sites for adaptations giving resistance to PDE inhibitors, resistance to the drug was induced. Selection of mutagenized trypanosomes resulted in resistance to CpdA as well as cross-resistance to membrane-permeable cAMP analogues but not to currently used trypanocidal drugs. Resistance was not due to changes in cAMP levels or in PDEB genes. A second approach, a genome-wide RNA interference (RNAi) library screen, returned four genes giving resistance to CpdA upon knockdown. Validation by independent RNAi strategies confirmed resistance to CpdA and suggested a role for the identified cAMP Response Proteins (CARPs) in cAMP action. CARP1 is unique to kinetoplastid parasites and has predicted cyclic nucleotide binding-like domains, and RNAi repression resulted in >100-fold resistance. CARP2 and CARP4 are hypothetical conserved proteins associated with the eukaryotic flagellar proteome or with flagellar function, with an orthologue of CARP4 implicated in human disease. CARP3 is a hypothetical protein, unique to Trypanosoma. CARP1 to CARP4 likely represent components of a novel cAMP signaling pathway in the parasite. As cAMP metabolism is validated as a drug target in Trypanosoma brucei, cAMP effectors highly divergent from the mammalian host, such as CARP1, lend themselves to further pharmacological development. PMID:23877697

Gould, Matthew K; Bachmaier, Sabine; Ali, Juma A M; Alsford, Sam; Tagoe, Daniel N A; Munday, Jane C; Schnaufer, Achim C; Horn, David; Boshart, Michael; de Koning, Harry P

2013-07-22

361

Screening for the interacting partners of the proteins MamK & MamJ by two-hybrid genomic DNA library of Magnetospirillum magneticum AMB-1.  

PubMed

Magnetotactic bacteria are a group of prokaryotes capable of sensing and navigating along the earth's magnetic field. The linear alignment of magnetosomes, which acts as a compass needle for orientation, is dependent on the proteins MamJ (amb0964) & MamK (amb0965). We constructed Magnetospirillum magneticum AMB-1 two-hybrid DNA libraries by fusing the random genomic fragments of AMB-1 to the N-terminal domain of the ?-subunit of RNA polymerase in vector pTRG and used as preys. The genes mamJ & mamK were cloned in frame with the ? repressor protein (? cI) in vector pBT and used as baits for screening the binding partners. After preliminary screening, we further confirmed the candidate interactions between selected protein pairs. The results showed that there were relatively strong interactions between MamK versus Amb3498 (flagella motor switch protein fliM), versus Amb0854 MCPs (signal domain of methyl-accepting chemotaxis protein) and versus Amb3568 (GGDEF domain-containing protein), respectively. MamJ versus Amb1722 (hypothetical protein), MamJ versus MamK, and MamK versus Amb1807 (cation transport ATPase) exhibited low level of interaction. Although the TPR repeat protein MamA (amb0971) showed no interaction with either MamJ or MamK, the TPR repeat protein Amb0024 with more motif sequences exhibited relatively strong interaction with MamK. Among the identified proteins, all categorized as signal transduction-related displayed interaction only with MamK and without MamJ, suggesting that magnetotaxis via MamK in Magnetospirillum magneticum AMB-1 might be somehow concerned with the widely accepted chemotaxis mechanism in bacteria. PMID:22382918

Pan, Weidong; Xie, Chunlan; Lv, Jing

2012-03-01

362

Genome Improvement at JGI-HAGSC  

SciTech Connect

Since the completion of the sequencing of the human genome, the JGI has rapidly expanded its scientific goals in several DOE mission-relevant areas. At the JGI-HAGSC, we have kept pace with this rapid expansion of projects with our focus on assessing, assembling, improving and finishing eukaryotic whole genome shotgun (WGS) projects for which the shotgun sequence is generated at the Production Genomic Facility (JGI-PGF). We follow this by combining the draft WGS with genomic resources generated at JGI-HAGSC or in collaborator laboratories (including BAC end sequences, genetic maps and FLcDNA sequences) to produce an improved draft sequence. For eukaryotic genomes important to the DOE mission, we then add further information from directed experiments to produce reference genomic sequences that are publicly available for any scientific researcher. Also, we have continued our program for producing BAC-based finished sequence, both for adding information to JGI genome projects and for small BAC-based sequencing projects proposed through any of the JGI sequencing programs. We have now built our computational expertise in WGS assembly and analysis and have moved eukaryotic genome assembly from the JGI-PGF to JGI-HAGSC. We have concentrated our assembly development work on large plant genomes and complex fungal and algal genomes.

Grimwood, Jane: Schmutz, Jeremy, J.: Myers, Richard, M.

2012-03-03

363

A re-assigned American mink (Neovison vison) map optimal for genome-wide studies.  

PubMed

Our previously published second generation genetic map for the American mink (Neovison vison) has been used and redesigned in its best for genome-wide studies with maximum of efficiency. A number of 114 selected markers, including 33 newly developed microsatellite markers from the CHORI-231 mink Bacterial Artificial Chromosome (BAC) library, have been genotyped in a two generation population composed of 1200 individuals. The outcome reassigns the position of some markers on the chromosomes and it produces a more reliable map with a convenient distance between markers. A total of 104 markers mapped to 14 linkage groups corresponding to the mink autosomes. Six markers are unlinked and four markers are allocated to the X chromosome by homology but no linkage was detected. The sex-average linkage map spans 1192 centiMorgans (cM) with an average intermarker distance of 11.4cM and 1648cM when the ends of the linkage groups and the autosomal unlinked markers are added. Sex-specific genetic linkage maps were also generated. The male sex-specific map had a total length of 1014.6cM between the linked markers and an average inter-marker interval of 9.7cM. The female map has a corresponding length of 1378.6cM and an average inter-marker interval of 13.3cM. The study is complemented with additional anchorage for most of the chromosomes of the map by BAC in situ hybridization with clones containing microsatellites strategically selected from the various parts of the genome. This map provides an improved tool for genetic mapping and comparative genomics in mink, also useful for the future assembly of the mink genome sequence when this will be taken forward. PMID:22982743

Anistoroaei, Razvan; Nielsen, Vivi; Markakis, Marios Nektarios; Karlskov-Mortensen, Peter; Jřrgensen, Claus B; Christensen, Knud; Fredholm, Merete

2012-09-12

364

Library 2000.  

ERIC Educational Resources Information Center

In fall 1984, the Georgia Institute of Technology administration and library staff began planning for Library 2000, a project aimed at creating a showcase library to demonstrate the application of the latest information technology in an academic and research environment. The purposes of Library 2000 include: increasing awareness of students,…

Drake, Miriam A.

365

Library Buildings.  

ERIC Educational Resources Information Center

|The innovative designs of three libraries are described: the Tempe (Arizona) Public Library, which emphasizes services for children and students; an underground library at Park College, Missouri; and a public library located in the Vancouver (Washington) Mall. The fourth article describes the work going on to restore the Los Angeles (California)…

Manley, Will; And Others

1989-01-01

366

The Pinus taeda genome is characterized by diverse and highly diverged repetitive sequences  

PubMed Central

Background In today's age of genomic discovery, no attempt has been made to comprehensively sequence a gymnosperm genome. The largest genus in the coniferous family Pinaceae is Pinus, whose 110-120 species have extremely large genomes (c. 20-40 Gb, 2N = 24). The size and complexity of these genomes have prompted much speculation as to the feasibility of completing a conifer genome sequence. Conifer genomes are reputed to be highly repetitive, but there is little information available on the nature and identity of repetitive units in gymnosperms. The pines have extensive genetic resources, with approximately 329000 ESTs from eleven species and genetic maps in eight species, including a dense genetic map of the twelve linkage groups in Pinus taeda. Results We present here the Sanger sequence and annotation of ten P. taeda BAC clones and Genome Analyzer II whole genome shotgun (WGS) sequences representing 7.5% of the genome. Computational annotation of ten BACs predicts three putative protein-coding genes and at least fifteen likely pseudogenes in nearly one megabase of sequence. We found three conifer-specific LTR retroelements in the BACs, and tentatively identified at least 15 others based on evidence from the distantly related angiosperms. Alignment of WGS sequences to the BACs indicates that 80% of BAC sequences have similar copies (? 75% nucleotide identity) elsewhere in the genome, but only 23% have identical copies (99% identity). The three most common repetitive elements in the genome were identified and, when combined, represent less than 5% of the genome. Conclusions This study indicates that the majority of repeats in the P. taeda genome are 'novel' and will therefore require additional BAC or genomic sequencing for accurate characterization. The pine genome contains a very large number of diverged and probably defunct repetitive elements. This study also provides new evidence that sequencing a pine genome using a WGS approach is a feasible goal.

2010-01-01

367

FISH mapping of 57 BAC clones reveals strong conservation of synteny between Galliformes and Anseriformes.  

PubMed

Karyotypes of chicken (Gallus gallus domesticus; 2n = 78) and mallard duck (Anas platyrhynchos; 2n = 80) share the typical organization of avian karyotypes including a few macrochromosome pairs, numerous indistinguishable microchromosomes, and Z and W sex chromosomes. Previous banding studies revealed great similarities between chickens and ducks, but it was not possible to use comparative banding for the microchromosomes. In order to establish precise chromosome correspondences between these two species, particularly for microchromosomes, we hybridized 57 BAC clones previously assigned to the chicken genome to duck metaphase spreads. Although most of the clones showed similar localizations, we found a few intrachromosomal rearrangements of the macrochromosomes and an additional microchromosome pair in ducks. BAC clones specific for chicken microchromosomes were localized to separate duck microchromosomes and clones mapping to the same chicken microchromosome hybridized to the same duck microchromosome, demonstrating a high conservation of synteny. These results demonstrate that the evolution of karyotypes in avian species is the result of fusion and/or fission processes and not translocations. PMID:17539975

Fillon, V; Vignoles, M; Crooijmans, R P M A; Groenen, M A M; Zoorob, R; Vignal, A

2007-06-01

368

A physical map of the human genome  

SciTech Connect

The human genome is by far the largest genome to be sequenced, and its size and complexity present many challenges for sequence assembly. The International Human Genome Sequencing Consortium constructed a map of the whole genome to enable the selection of clones for sequencing and for the accurate assembly of the genome sequence. Here we report the construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions. We also describe the integration of sequence data with the map.

McPherson, J.D.; Marra, M.; Hillier, L.; Waterston, R.H.; Chinwalla, A.; Wallis, J.; Sekhon, M.; Wylie, K.; Mardis, E.R.; Wilson, R.K.; Fulton, R.; Kucaba, T.A.; Wagner-McPherson, C.; Barbazuk, W.B.; Gregory, S.G.; Humphray, S.J.; French, L.; Evans, R.S.; Bethel, G.; Whittaker, A.; Holden, J.L.; McCann, O.T.; Dunham, A.; Soderlund, C.; Scott, C.E.; Bentley, D.R.; Schuler, G.; Chen, H.-C.; Jang, W.; Green, E.D.; Idol, J.R.; Maduro, V.V. Braden; Montgomery, K.T.; Lee, E.; Miller, A.; Emerling, S.; Kucherlapati; Gibbs, R.; Scherer, S.; Gorrell, J.H.; Sodergren, E.; Clerc-Blankenburg, K.; Tabor, P.; Naylor, S.; Garcia, D.; de Jong, P.J.; Catanese, J.J.; Nowak, N.; Osoegawa, K.; Qin, S.; Rowen, L.; Madan, A.; Dors, M.; Hood, L.; Trask, B.; Friedman, C.; Massa, H.; Cheung, V.G.; Kirsch, I.R.; Reid, T.; Yonescu, R.; Weissenbach, J.; Bruls, T.; Heilig, R.; Branscomb, E.; Olsen, A.; Doggett, N.; Cheng, J.F.; Hawkins, T.; Myers, R.M.; Shang, J.; Ramirez, L.; Schmutz, J.; Velasquez, O.; Dixon, K.; Stone, N.E.; Cox, D.R.; Haussler, D.; Kent, W.J.; Furey, T.; Rogic, S.; Kennedy, S.; Jones, S.; Rosenthal, A.; Wen, G.; Schilhabel, M.; Gloeckner, G.; Nyakatura, G.; Siebert, R.; Schlegelberger, B.; Korenberg, J.; Chen, X.N.; Fujiyama, A.; Hattori, M.; Toyoda, A.; Yada, T.; Park, H.S.; Sakaki, Y.; Shimizu, N.; Asakawa, S.; Kawasaki, K.; Sasaki, T.; Shintani, A.; Shimizu, A.; Shibuya, K.; Kudoh, J.; Minoshima, S.; Ramser, J.; Seranski, P.; Hoff, C.; Poustka, A.; Reinhardt, R.; Lehrach, H.

2001-01-01

369

[Developing a physical map of human chromosome 22 using Pace electrophoresis and large fragment cloning]. Annual report, October 1, 1991--July 1, 1994  

SciTech Connect

In the past two years, the authors have made a great deal of progress in establishing Fosmid and BAC libraries and in using large BAC libraries for gene mapping. In addition, they initiated work on the application of BAC clones to long range genome sequencing. They continue to increase the ability to rapidly generate large BAC libraries and to efficiently apply these libraries to genome mapping. The BACs provide a very effective means of developing physical maps. The current work suggests that BAC contigs will be extremely useful as source material for genome sequencing.

Simon, M.I.

1994-12-31

370

The Ensembl Core Software Libraries  

PubMed Central

Systems for managing genomic data must store a vast quantity of information. Ensembl stores these data in several MySQL databases. The core software libraries provide a practical and effective means for programmers to access these data. By encapsulating the underlying database structure, the libraries present end users with a simple, abstract interface to a complex data model. Programs that use the libraries rather than SQL to access the data are unaffected by most schema changes. The architecture of the core software libraries, the schema, and the factors influencing their design are described. All code and data are freely available.

Stabenau, Arne; McVicker, Graham; Melsopp, Craig; Proctor, Glenn; Clamp, Michele; Birney, Ewan

2004-01-01

371

A Community-Based Feedback Process for Disseminating Pedestrian BAC Levels  

Microsoft Academic Search

During National Collegiate Alcohol Awareness Weeks of 1992, 1994, and 1995, blood alcohol concentration (BAC) feedback was offered to pedestrians. Two BAC feedback stations were set up near bars frequented by many university students, and were staffed for either two or three consecutive nights. These stations provided passers-by with their. BAC, as determined by portable breathalyzers. Across the three years

Kent E. Glindemann; E. Scott Geller; Steven W. Clarke; Candice R. Chevaillier; Charles B. Pettinger

1998-01-01

372

A new genomic tool, ultra-frequently cleaving TaqII/sinefungin endonuclease with a combined 2.9-bp recognition site, applied to the construction of horse DNA libraries  

PubMed Central

Background Genomics and metagenomics are currently leading research areas, with DNA sequences accumulating at an exponential rate. Although enormous advances in DNA sequencing technologies are taking place, progress is frequently limited by factors such as genomic contig assembly and generation of representative libraries. A number of DNA fragmentation methods, such as hydrodynamic sharing, sonication or DNase I fragmentation, have various drawbacks, including DNA damage, poor fragmentation control, irreproducibility and non-overlapping DNA segment representation. Improvements in these limited DNA scission methods are consequently needed. An alternative method for obtaining higher quality DNA fragments involves partial digestion with restriction endonucleases (REases). We have shown previously that class-IIS/IIC/IIG TspGWI REase, the prototype member of the Thermus sp. enzyme family, can be chemically relaxed by a cofactor analogue, allowing it to recognize very short DNA sequences of 3-bp combined frequency. Such frequently cleaving REases are extremely rare, with CviJI/CviJI*, SetI and FaiI the only other ones found in nature. Their unusual features make them very useful molecular tools for the development of representative DNA libraries. Results We constructed a horse genomic library and a deletion derivative library of the butyrylcholinesterase cDNA coding region using a novel method, based on TaqII, Thermus sp. family bifunctional enzyme exhibiting cofactor analogue specificity relaxation. We used sinefungin (SIN) – an S-adenosylmethionine (SAM) analogue with reversed charge pattern, and dimethylsulfoxide (DMSO), to convert the 6-bp recognition site TaqII (5?-GACCGA-3? [11/9]) into a theoretical 2.9-bp REase, with 70 shortened variants of the canonical recognition sequence detected. Because partial DNA cleavage is an inherent feature of the Thermus sp. enzyme family, this modified TaqII is uniquely suited to quasi-random library generation. Conclusions In the presence of SIN/DMSO, TaqII REase is transformed from cleaving every 4096 bp on average to cleaving every 58 bp. TaqII SIN/DMSO thus extends the palette of available REase prototype specificities. This phenomenon, employed under partial digestion conditions, was applied to quasi-random DNA fragmentation. Further applications include high sensitivity probe generation and metagenomic DNA amplification.

2013-01-01

373

A PiggyBac-Based Recessive Screening Method to Identify Pluripotency Regulators  

PubMed Central

Phenotype driven genetic screens allow unbiased exploration of the genome to discover new biological regulators. Bloom syndrome gene (Blm) deficient embryonic stem (ES) cells provide an opportunity for recessive screening due to frequent loss of heterozygosity. We describe a strategy for isolating regulators of mammalian pluripotency based on conversion to homozygosity of PiggyBac gene trap insertions combined with stringent selection for differentiation resistance. From a screen of 2000 mutants we obtained a disruptive integration in the Tcf3 gene. Homozygous Tcf3 mutants showed impaired differentiation and enhanced self-renewal. This phenotype was reverted in a dosage sensitive manner by excision of one or both copies of the gene trap. These results provide new evidence confirming that Tcf3 is a potent negative regulator of pluripotency and validate a forward screening methodology to identify modulators of pluripotent stem cell biology.

Guo, Ge; Huang, Yue; Humphreys, Peter; Wang, Xiaozhong; Smith, Austin

2011-01-01

374

A physical map of the highly heterozygous Populus genome: integration with the genome sequence and genetic map and analysis of haplotype variation  

Microsoft Academic Search

Summary As part of a larger project to sequence the Populus genome and generate genomic resources for this emerging model tree, we constructed a physical map of the Populus genome, representing one of the few such maps of an undomesticated, highly heterozygous plant species. The physical map, consisting of 2802 contigs, was constructed from fingerprinted bacterial artificial chromosome (BAC) clones.

Colin T. Kelleher; Readman Chiu; Heesun Shin; Ian E. Bosdet; Martin I. Krzywinski; Chris D. Fjell; Jennifer Wilkin; TongMing Yin; Stephen P. DiFazio; Johar Ali; Jennifer K. Asano; Susanna Chan; Alison Cloutier; Noreen Girn; Stephen Leach; Darlene Lee; Carrie A. Mathewson; Teika Olson; Katie O'Connor; Anna-Liisa Prabhu; Duane E. Smailus; Jeffery M. Stott; Miranda Tsai; Natasja H. Wye; George S. Yang; Jun Zhuang; Robert A. Holt; Nicholas H. Putnam; Julia Vrebalov; James J. Giovannoni; Jane Grimwood; Daniel Rokhsar; Steven J. M. Jones; Marco A. Marra; Gerald A. Tuskan; Brian E. Ellis; Kermit Ritland; Carl J. Douglas; Jacqueline E. Schein

2007-01-01

375

Cloning human herpes virus 6A genome into bacterial artificial chromosomes and study of DNA replication intermediates  

PubMed Central

Cloning of large viral genomes into bacterial artificial chromosomes (BACs) facilitates analyses of viral functions and molecular mutagenesis. Previous derivations of viral BACs involved laborious recombinations within infected cells. We describe a single-step production of viral BACs by direct cloning of unit length genomes, derived from circular or head-to-tail concatemeric DNA replication intermediates. The BAC cloning is independent of intracellular recombinations and DNA packaging constraints. We introduced the 160-kb human herpes virus 6A (HHV-6A) genome into BACs by digesting the viral DNA replicative intermediates with the Sfil enzyme that cleaves the viral genome in a single site. The recombinant BACs contained also the puromycin selection gene, GFP, and LoxP sites flanking the BAC sequences. The HHV-6A-BAC vectors were retained stably in puromycin selected 293T cells. In the presence of irradiated helper virus, supplying most likely proteins enhancing gene expression they expressed early and late genes in SupT1 T cells. The method is especially attractive for viruses that replicate inefficiently and for viruses propagated in suspension cells. We have used the fact that the BAC cloning “freezes” the viral DNA replication intermediates to analyze their structure. The results revealed that HHV-6A-BACs contained a single direct repeat (DR) rather than a DR-DR sequence, predicted to arise by circularization of parental genomes with a DR at each terminus. HHV-6A DNA molecules prepared from the infected cells also contained DNA molecules with a single DR. Such forms were not previously described for HHV-6 DNA.

Borenstein, Ronen; Frenkel, Niza

2009-01-01

376

Gene duplication and paleopolyploidy in soybean and the implications for whole genome sequencing  

PubMed Central

Background Soybean, Glycine max (L.) Merr., is a well documented paleopolyploid. What remains relatively under characterized is the level of sequence identity in retained homeologous regions of the genome. Recently, the Department of Energy Joint Genome Institute and United States Department of Agriculture jointly announced the sequencing of the soybean genome. One of the initial concerns is to what extent sequence identity in homeologous regions would have on whole genome shotgun sequence assembly. Results Seventeen BACs representing ~2.03 Mb were sequenced as representative potential homeologous regions from the soybean genome. Genetic mapping of each BAC shows that 11 of the 20 chromosomes are represented. Sequence comparisons between homeologous BACs shows that the soybean genome is a mosaic of retained paleopolyploid regions. Some regions appear to be highly conserved while other regions have diverged significantly. Large-scale "batch" reassembly of all 17 BACs combined showed that even the most homeologous BACs with upwards of 95% sequence identity resolve into their respective homeologous sequences. Potential assembly errors were generated by tandemly duplicated pentatricopeptide repeat containing genes and long simple sequence repeats. Analysis of a whole-genome shotgun assembly of 80,000 randomly chosen JGI-DOE sequence traces reveals some new soybean-specific repeat sequences. Conclusion This analysis investigated both the structure of the paleopolyploid soybean genome and the potential effects retained homeology will have on assembling the whole genome shotgun sequence. Based upon these results, homeologous regions similar to those characterized here will not cause major assembly issues.

Schlueter, Jessica A; Lin, Jer-Young; Schlueter, Shannon D; Vasylenko-Sanders, Iryna F; Deshpande, Shweta; Yi, Jing; O'Bleness, Majesta; Roe, Bruce A; Nelson, Rex T; Scheffler, Brian E; Jackson, Scott A; Shoemaker, Randy C

2007-01-01

377

SweetBac: A New Approach for the Production of Mammalianised Glycoproteins in Insect Cells  

PubMed Central

Recombinant production of therapeutically active proteins has become a central focus of contemporary life science research. These proteins are often produced in mammalian cells, in order to obtain products with post-translational modifications similar to their natural counterparts. However, in cases where a fast and flexible system for recombinant production of proteins is needed, the use of mammalian cells is limited. The baculoviral insect cell system has proven to be a powerful alternative for the expression of a wide range of recombinant proteins in short time frames. The major drawback of baculoviral systems lies in the inability to perform mammalian-like glycosylation required for the production of therapeutic glycoproteins. In this study we integrated sequences encoding Caenorhabditis elegans N-acetylglucosaminyltransferase II and bovine ?1,4-galactosyltransferase I into the backbone of a baculovirus genome. The thereby generated SweetBac virus was subsequently used for the production of the human HIV anti-gp41 antibody 3D6 by integrating heavy and light chain open reading frames into the SweetBac genome. The parallel expression of target genes and glycosyltransferases reduced the yield of secreted antibody. However, the overall expression rate, especially in the recently established Tnao38 cell line, was comparable to that of transient expression in mammalian cells. In order to evaluate the ability of SweetBac to generate mammalian-like N-glycan structures on 3D6 antibody, we performed SDS-PAGE and tested for the presence of terminal galactose using Riccinus communis agglutinin I. The mammalianised variants of 3D6 showed highly specific binding to the lectin, indicating proper functionality. To confirm these results, PNGase A released N-glycans were analyzed by MALDI-TOF-MS and shown to contain structures with mainly one or two terminal galactose residues. Since the presence of specific N-glycans has an impact on antibodies ability to exert different effector functions, we tested the binding to human Fc gamma receptor I present on U937 cells.

Palmberger, Dieter; Wilson, Iain B. H.; Berger, Imre; Grabherr, Reingard; Rendic, Dubravko

2012-01-01

378

CFTR expression and activity from the human CFTR locus in BAC vectors, with regulatory regions, isolated by a single-step procedure.  

PubMed

We have assembled two BAC vectors containing a single fragment spanning the entire CFTR locus and including the upstream and downstream regions. The two vectors differ in size of the upstream region, and were recovered in Escherichia coli, with intact BAC DNAs prepared for structural and functional analyses. Sequence analysis allowed precise mapping of the inserts. We show that the CFTR gene was wild type and is categorized as the most frequent haplotype in Caucasian populations, identified by the following polymorphisms: (GATT)? in intron 6a; (TG)??T? in intron 8; V470 at position 470. CFTR expression and activity were analyzed in model cells by RT-PCR, quantitative real-time PCR, western blotting, indirect immunofluorescence and electrophysiological methods, which show the presence of an active CFTR Cl?? channel. Finally, and supporting the hypothesis that CFTR functions as a receptor for Pseudomonas aeruginosa, we show that CFTR-expressing cells internalized more bacteria than parental cells that do not express CFTR. Overall, these data demonstrate that the BAC vectors contain a functional CFTR fragment and have unique features, including derivation from a single fragment, availability of a detailed genomic map and the possibility to use standard extraction procedures for BAC DNA preparations. PMID:20535216

Auriche, C; Di Domenico, E G; Pierandrei, S; Lucarelli, M; Castellani, S; Conese, M; Melani, R; Zegarra-Moran, O; Ascenzioni, F

2010-06-10

379

Cloning of the Koi Herpesvirus Genome as an Infectious Bacterial Artificial Chromosome Demonstrates That Disruption of the Thymidine Kinase Locus Induces Partial Attenuation in Cyprinus carpio koi  

Microsoft Academic Search

Koi herpesvirus (KHV) is the causative agent of a lethal disease in koi and common carp. In the present study, we describe the cloning of the KHV genome as a stable and infectious bacterial artificial chromosome (BAC) clone that can be used to produce KHV recombinant strains. This goal was achieved by the insertion of a loxP-flanked BAC cassette into

B. Costes; G. Fournier; B. Michel; C. Delforge; V. Stalin Raj; B. Dewals; L. Gillet; P. Drion; A. Body; F. Schynts; F. Lieffrig; A. Vanderplasschen

2008-01-01

380

Chromosomal Breakpoints in Primary Colon Cancer Cluster at Sites of Structural Variants in the Genome  

Microsoft Academic Search

Genomic aberrations on chromosome 8 are common in colon cancer, and are associated with lymph node and distant metastases as well as with disease susceptibility. This prompted us to generate a high-resolution map of genomic imbalances of chromosome 8 in 51 primary colon carcinomas using a custom-designed genomic array consisting of a tiling path of BAC clones. This analysis confirmed

Jordi Camps; Quang Tri Nguyen; Patrick Hormann; Sandra Becker; Amanda B. Hummon; Virginia Rodriguez; Settara Chandrasekharappa; Yidong Chen; Michael J. Difilippantonio; Heinz Becker; B. Michael Ghadimi

2008-01-01

381

Library Statistics Cooperative Program.  

ERIC Educational Resources Information Center

The Library Statistics Cooperative Program collects statistics about all types of libraries--academic libraries, public libraries, school library media centers, state library agencies, federal libraries and information centers, and library cooperatives. The Library Statistics Cooperative Program depends on collaboration with all types of libraries

National Commission on Libraries and Information Science, Washington, DC.

382

Legume Genome Initiative at the University of Oklahoma  

SciTech Connect

Consolidated Appropriations Resolution, 2003 Conference Report for the Department of Energy's Biological and Environmental Research (BER) program provided $481,000 for the Legume Genome Initiative at the University of Oklahoma. These funds were used to support our research that is aimed at determining the entire sequence of the gene rich regions of the genome of the legume, Medicago truncatula, by allowing us to obtain a greater degree of finished BAC sequences from the draft sequences we have already obtained through research funded by the Noble Foundation. During the funding period we increased the number of Medicago truncatula BACs with finished (Bermuda standard) sequences from 109 to 359, and the total number of BACs for which we collected sequence data from 584 to 842, 359 of which reached phase 2 (ordered and oriented contigs). We also sequenced a series of pooled BAC clones that cover additional euchromatic (gene rich) genomic regions. This work resulted in 6 refereed publications, see below. Genes whose sequence was determined during this study included multiple members of the plant disease resistance (R-gene) family as well as several genes involved in flavinoid biosynthesis, nitrogen fixation and plant-microbial symbosis. This work also served as a prelude to obtaining NSF funding for the international collaborative effort to complete the entire sequence of the Medicago truncatula genomic euchromatic regions using a BAC based approach.

Bruce A. Roe

2004-02-27

383

Genomic evolution in Barrett's adenocarcinoma cells: critical roles of elevated hsRAD51, homologous recombination and Alu sequences in the genome.  

PubMed

A prominent feature of most cancers including Barrett's adenocarcinoma (BAC) is genetic instability, which is associated with development and progression of disease. In this study, we investigated the role of recombinase (hsRAD51), a key component of homologous recombination (HR)/repair, in evolving genomic changes and growth of BAC cells. We show that the expression of RAD51 is elevated in BAC cell lines and tissue specimens, relative to normal cells. HR activity is also elevated and significantly correlates with RAD51 expression in BAC cells. The suppression of RAD51 expression, by short hairpin RNA (shRNA) specifically targeting this gene, significantly prevented BAC cells from acquiring genomic changes to either copy number or heterozygosity (P<0.02) in several independent experiments employing single-nucleotide polymorphism arrays. The reduction in copy-number changes, following shRNA treatment, was confirmed by Comparative Genome Hybridization analyses of the same DNA samples. Moreover, the chromosomal distributions of mutations correlated strongly with frequencies and locations of Alu interspersed repetitive elements on individual chromosomes. We conclude that the hsRAD51 protein level is systematically elevated in BAC, contributes significantly to genomic evolution during serial propagation of these cells and correlates with disease progression. Alu sequences may serve as substrates for elevated HR during cell proliferation in vitro, as they have been reported to do during the evolution of species, and thus may provide additional targets for prevention or treatment of this disease. PMID:21423218

Pal, J; Bertheau, R; Buon, L; Qazi, A; Batchu, R B; Bandyopadhyay, S; Ali-Fehmi, R; Beer, D G; Weaver, D W; Shmookler Reis, R J; Goyal, R K; Huang, Q; Munshi, N C; Shammas, M A

2011-03-21

384

Physical mapping of a large plant genome using global high-information-content-fingerprinting: the distal region of the wheat ancestor Aegilops tauschii chromosome 3DS  

PubMed Central

Background Physical maps employing libraries of bacterial artificial chromosome (BAC) clones are essential for comparative genomics and sequencing of large and repetitive genomes such as those of the hexaploid bread wheat. The diploid ancestor of the D-genome of hexaploid wheat (Triticum aestivum), Aegilops tauschii, is used as a resource for wheat genomics. The barley diploid genome also provides a good model for the Triticeae and T. aestivum since it is only slightly larger than the ancestor wheat D genome. Gene co-linearity between the grasses can be exploited by extrapolating from rice and Brachypodium distachyon to Ae. tauschii or barley, and then to wheat. Results We report the use of Ae. tauschii for the construction of the physical map of a large distal region of chromosome arm 3DS. A physical map of 25.4 Mb was constructed by anchoring BAC clones of Ae. tauschii with 85 EST on the Ae. tauschii and barley genetic maps. The 24 contigs were aligned to the rice and B. distachyon genomic sequences and a high density SNP genetic map of barley. As expected, the mapped region is highly collinear to the orthologous chromosome 1 in rice, chromosome 2 in B. distachyon and chromosome 3H in barley. However, the chromosome scale of the comparative maps presented provides new insights into grass genome organization. The disruptions of the Ae. tauschii-rice and Ae. tauschii-Brachypodium syntenies were identical. We observed chromosomal rearrangements between Ae. tauschii and barley. The comparison of Ae. tauschii physical and genetic maps showed that the recombination rate across the region dropped from 2.19 cM/Mb in the distal region to 0.09 cM/Mb in the proximal region. The size of the gaps between contigs was evaluated by comparing the recombination rate along the map with the local recombination rates calculated on single contigs. Conclusions The physical map reported here is the first physical map using fingerprinting of a complete Triticeae genome. This study demonstrates that global fingerprinting of the large plant genomes is a viable strategy for generating physical maps. Physical maps allow the description of the co-linearity between wheat and grass genomes and provide a powerful tool for positional cloning of new genes.

2010-01-01

385

Insulated piggyBac vectors for insect transgenesis  

Microsoft Academic Search

BACKGROUND: Germ-line transformation of insects is now a widely used method for analyzing gene function and for the development of genetically modified strains suitable for pest control programs. The most widely used transposable element for the germ-line transformation of insects is piggyBac. The site of integration of the transgene can influence gene expression due to the effects of nearby transcription

Abhimanyu Sarkar; Asela Atapattu; Esther J Belikoff; Jörg C Heinrich; Xuelei Li; Carsten Horn; Ernst A Wimmer; Maxwell J Scott

2006-01-01

386

Genomics Glossary  

NSDL National Science Digital Library

Because genomics is an interdisciplinary science that unites biology, chemistry, physics, and mathematics, its language is diverse and includes terms not always found in dictionaries. This site from Cambridge Healthtech Institute of Massachusetts was designed to help scientists keep on top of this complex language. Loads of terms in categories such as basic genetics, functional and structural genomics, informatics, and genomic-related technology are defined here. Users can access the glossary terms either through a short index of major subject headings or by a longer alphabetically-arranged subject list. The Genomics Glossary deserves bonus points for including links to related resources in the text of its definitions. For example, within the definition of "polymerase chain reaction" are links to sites at Yale Medical School and the National Library of Medicine. In addition, links to pages on nomenclature, a bibliography of Web and print resources, and a FAQ page are available at this fantastic Website.

Chitty, Mary G.

387

CpG Island microarray probe sequences derived from a physical library are representative of CpG Islands annotated on the human genome  

Microsoft Academic Search

An effective tool for the global analysis of both DNA methylation status and protein-chromatin interac- tions is a microarray constructed with sequences containing regulatory elements. One type of array sui- ted for this purpose takes advantage of the strong association between CpG Islands (CGIs) and gene regulatory regions. We have obtained 20 736 clones from a CGI Library and used

Lawrence E. Heisler; Dax Torti; Paul C. Boutros; Charles Chan; Neil Winegarden; Mark Takahashi; Patrick Yau; Tim H.-M. Huang; Peggy J. Farnham; Igor Jurisica; James R. Woodgett; Rod Bremner; Linda Z. Penn; Sandy D. Der

2005-01-01

388

Libraries program  

USGS Publications Warehouse

The U.S. Congress authorized a library for the U.S. Geological Survey (USGS) in 1879. The library was formally established in 1882 with the naming of the first librarian and began with a staff of three and a collection of 1,400 books. Today, the USGS Libraries Program is one of the world's largest Earth and natural science repositories and a resource of national significance used by researchers and the public worldwide.

2011-01-01

389

The multiBac protein complex production platform at the EMBL.  

PubMed

Proteomics research revealed the impressive complexity of eukaryotic proteomes in unprecedented detail. It is now a commonly accepted notion that proteins in cells mostly exist not as isolated entities but exert their biological activity in association with many other proteins, in humans ten or more, forming assembly lines in the cell for most if not all vital functions.(1,2) Knowledge of the function and architecture of these multiprotein assemblies requires their provision in superior quality and sufficient quantity for detailed analysis. The paucity of many protein complexes in cells, in particular in eukaryotes, prohibits their extraction from native sources, and necessitates recombinant production. The baculovirus expression vector system (BEVS) has proven to be particularly useful for producing eukaryotic proteins, the activity of which often relies on post-translational processing that other commonly used expression systems often cannot support.(3) BEVS use a recombinant baculovirus into which the gene of interest was inserted to infect insect cell cultures which in turn produce the protein of choice. MultiBac is a BEVS that has been particularly tailored for the production of eukaryotic protein complexes that contain many subunits.(4) A vital prerequisite for efficient production of proteins and their complexes are robust protocols for all steps involved in an expression experiment that ideally can be implemented as standard operating procedures (SOPs) and followed also by non-specialist users with comparative ease. The MultiBac platform at the European Molecular Biology Laboratory (EMBL) uses SOPs for all steps involved in a multiprotein complex expression experiment, starting from insertion of the genes into an engineered baculoviral genome optimized for heterologous protein production properties to small-scale analysis of the protein specimens produced.(5-8) The platform is installed in an open-access mode at EMBL Grenoble and has supported many scientists from academia and industry to accelerate protein complex research projects. PMID:23892976

Berger, Imre; Garzoni, Frederic; Chaillet, Maxime; Haffke, Matthias; Gupta, Kapil; Aubert, Alice

2013-07-11

390

Somatic transformation efficiencies and expression patterns using the JcDNV and piggyBac transposon gene vectors in insects.  

PubMed

A somatic transformation gene vector that exploits the genomic integration properties of Junonia coenia lepidopteran densovirus (JcDNV) sequences in vivo has been developed. JcDNV somatic transformation vectors are derivatives of plasmids containing an interrupted genome of JcDNV that provide efficient, robust vectors that can be used to examine regulation of chromosomally integrated transgenes in insects. Microinjection of JcDNV plasmids into syncytial embryos of Drosophila melanogaster or the lepidopterans Plodia interpunctella, Ephestia kuehniella or Trichoplusia ni resulted in persistent transgene expression throughout development. Inclusion of transgenes with tissue-specific promoters resulted in expression patterns canonical with phenotypes of piggyBac germline transformants. Somatic transformation required the presence of the viral inverted terminal repeat in cis only and did not depend upon non-structural viral proteins. PMID:17257207

Bossin, H; Furlong, R B; Gillett, J L; Bergoin, M; Shirk, P D

2007-02-01

391

Libraries and Library Services in Botswana  

Microsoft Academic Search

Describes in outline the main libraries in Botswana and their services, including: the University of Botswana Library and its branch libraries, the Documentation Centre of the National Institute of Development Research and Documentation (NIR), the Botswana National Library Service (BNLS) and its components, including the National Reference Library (NRL), the Gaborone Public Library, branch libraries and outreach services, Village Reading

Rose Tiny Kgosiemang

1999-01-01

392

Genome Mapping and Molecular Breeding of Tomato  

PubMed Central

The cultivated tomato, Lycopersicon esculentum, is the second most consumed vegetable worldwide and a well-studied crop species in terms of genetics, genomics, and breeding. It is one of the earliest crop plants for which a genetic linkage map was constructed, and currently there are several molecular maps based on crosses between the cultivated and various wild species of tomato. The high-density molecular map, developed based on an L. esculentum × L. pennellii cross, includes more than 2200 markers with an average marker distance of less than 1?cM and an average of 750?kbp per cM. Different types of molecular markers such as RFLPs, AFLPs, SSRs, CAPS, RGAs, ESTs, and COSs have been developed and mapped onto the 12 tomato chromosomes. Markers have been used extensively for identification and mapping of genes and QTLs for many biologically and agriculturally important traits and occasionally for germplasm screening, fingerprinting, and marker-assisted breeding. The utility of MAS in tomato breeding has been restricted largely due to limited marker polymorphism within the cultivated species and economical reasons. Also, when used, MAS has been employed mainly for improving simply-inherited traits and not much for improving complex traits. The latter has been due to unavailability of reliable PCR-based markers and problems with linkage drag. Efforts are being made to develop high-throughput markers with greater resolution, including SNPs. The expanding tomato EST database, which currently includes ?214?000 sequences, the new microarray DNA chips, and the ongoing sequencing project are expected to aid development of more practical markers. Several BAC libraries have been developed that facilitate map-based cloning of genes and QTLs. Sequencing of the euchromatic portions of the tomato genome is paving the way for comparative and functional analysis of important genes and QTLs.

Foolad, Majid R.

2007-01-01

393

BAC-Based Sequencing of Behaviorally-Relevant Genes in the Prairie Vole  

PubMed Central

The prairie vole (Microtus ochrogaster) is an important model organism for the study of social behavior, yet our ability