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Sample records for artificial chromosome clone

  1. Complete Genome Sequence of a Human Cytomegalovirus Strain AD169 Bacterial Artificial Chromosome Clone

    Science.gov (United States)

    Ostermann, Eleonore; Spohn, Michael; Indenbirken, Daniela

    2016-01-01

    The complete sequence of the human cytomegalovirus strain AD169 (variant ATCC) cloned as a bacterial artificial chromosome (AD169-BAC, also known as HB15 or pHB15) was determined. The viral genome has a length of 230,290 bp and shows 52 nucleotide differences compared to a previously sequenced AD169varATCC clone. PMID:27034483

  2. Drought-tolerant rice germplasm developed from an Oryza officinalis transformation-competent artificial chromosome clone.

    Science.gov (United States)

    Liu, R; Zhang, H H; Chen, Z X; Shahid, M Q; Fu, X L; Liu, X D

    2015-10-29

    Oryza officinalis has proven to be a natural gene reservoir for the improvement of domesticated rice as it carries many desirable traits; however, the transfer of elite genes to cultivated rice by conventional hybridization has been a challenge for rice breeders. In this study, the conserved sequence of plant stress-related NAC transcription factors was selected as a probe to screen the O. officinalis genomic transformation-competent artificial chromosome library by Southern blot; 11 positive transformation-competent artificial chromosome clones were subsequently detected. By Agrobacterium-mediated transformation, an indica rice variety, Huajingxian 74 (HJX74), was transformed with a TAC clone harboring a NAC gene-positive genomic fragment from O. officinalis. Molecular analysis revealed that the O. officinalis genomic fragment was integrated into the genome of HJX74. The transgenic lines exhibited high tolerance to drought stress. Our results demonstrate that the introduction of stress-related transformation-competent artificial chromosome clones, coupled with a transgenic validation approach, is an effective method of transferring agronomically important genes from O. officinalis to cultivated rice.

  3. Complete Genomes of Classical Swine Fever Virus Cloned into Bacterial Artificial Chromosomes

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Reimann, I.; Uttenthal, Åse;

    Complete genome amplification of viral RNA provides a new tool for the generation of modified pestiviruses. We have used our full-genome amplification strategy for generation of amplicons representing complete genomes of classical swine fever virus. The amplicons were cloned directly into a stabl...... single-copy bacterial artificial chromosome (BAC) generating full-length pestivirus DNAs from which infectious RNA transcripts could be also derived. Our strategy allows construction of stable infectious BAC DNAs from a single full-length PCR product....

  4. Pathogenicity of a Very Virulent Strain of Marek's Disease Herpesvirus Cloned as Infectious Bacterial Artificial Chromosomes

    Directory of Open Access Journals (Sweden)

    Lorraine P. Smith

    2011-01-01

    Full Text Available Bacterial artificial chromosome (BAC vectors containing the full-length genomes of several herpesviruses have been used widely as tools to enable functional studies of viral genes. Marek's disease viruses (MDVs are highly oncogenic alphaherpesviruses that induce rapid-onset T-cell lymphomas in chickens. Oncogenic strains of MDV reconstituted from BAC clones have been used to examine the role of viral genes in inducing tumours. Past studies have demonstrated continuous increase in virulence of MDV strains. We have previously reported on the UK isolate C12/130 that showed increased virulence features including lymphoid organ atrophy and enhanced tropism for the central nervous system. Here we report the construction of the BAC clones (pC12/130 of this strain. Chickens were infected with viruses reconstituted from the pC12/130 clones along with the wild-type virus for the comparison of the pathogenic properties. Our studies show that BAC-derived viruses induced disease similar to the wild-type virus, though there were differences in the levels of pathogenicity between individual viruses. Generation of BAC clones that differ in the potential to induce cytolytic disease provide the opportunity to identify the molecular determinants of increased virulence by direct sequence analysis as well as by using reverse genetics approaches on the infectious BAC clones.

  5. Use of Recombination-Mediated Genetic Engineering for Construction of Rescue Human Cytomegalovirus Bacterial Artificial Chromosome Clones

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    Kalpana Dulal

    2012-01-01

    Full Text Available Bacterial artificial chromosome (BAC technology has contributed immensely to manipulation of larger genomes in many organisms including large DNA viruses like human cytomegalovirus (HCMV. The HCMV BAC clone propagated and maintained inside E. coli allows for accurate recombinant virus generation. Using this system, we have generated a panel of HCMV deletion mutants and their rescue clones. In this paper, we describe the construction of HCMV BAC mutants using a homologous recombination system. A gene capture method, or gap repair cloning, to seize large fragments of DNA from the virus BAC in order to generate rescue viruses, is described in detail. Construction of rescue clones using gap repair cloning is highly efficient and provides a novel use of the homologous recombination-based method in E. coli for molecular cloning, known colloquially as recombineering, when rescuing large BAC deletions. This method of excising large fragments of DNA provides important prospects for in vitro homologous recombination for genetic cloning.

  6. Identification and Preliminary Analysis of Several Centromere-associated Bacterial Artificial Chromosome Clones from a Diploid Wheat Library

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Although the centromeres of some plants have been investigated previously, our knowledge of the wheat centromere is still very limited. To understand the structure and function of the wheat centromere, we used two centromeric repeats (RCS1 and CCS1-5ab) to obtain some centromere-associated bacterial artificial chromosome (BAC) clones in 32 RCS1-related BAC clones that had been screened out from a diploid wheat (Triticum boeoticum Boiss.; 2n=2x=14) BAC library. Southern hybridization results indicated that, of the 32 candidates,there were 28 RCS1-positive clones. Based on gel blot patterns, the frequency of RCS1 was approximately one copy every 69.4 kb in these 28 RCS1-positive BAC clones. More bands were detected when the same filter was probed with CCS1-5ab. Furthermore, the CCS1 bands covered all the bands detected by RCS1, which suggests that some CCS1 repeats were distributed together with RCS1. The frequency of CCS1 families was once every 35.8 kb, nearly twice that of RCS1. Fluorescence in situ hybridization (FISH) analysis indicated that the five BAC clones containing RCS1 and CCS1 sequences all detected signals at the centromeric regions in hexaploid wheat, but the signal intensities on the A-genome chromosomes were stronger than those on the B- and/or D-genome chromosomes. The FISH analysis among nine Triticeae cereals indicated that there were A-genomespecific (or rich) sequences dispersing on chromosome arms in the BAC clone TbBAC5. In addition, at the interphase cells, the centromeres of diploid species usually clustered at one pole and formed a ring-like allocation in the period before metaphase.

  7. Recombination-mediated genetic engineering of a bacterial artificial chromosome clone of modified vaccinia virus Ankara (MVA)

    DEFF Research Database (Denmark)

    Cottingham, Matthew G; Andersen, Rikke F; Spencer, Alexandra J

    2008-01-01

    The production, manipulation and rescue of a bacterial artificial chromosome clone of Vaccinia virus (VAC-BAC) in order to expedite construction of expression vectors and mutagenesis of the genome has been described (Domi & Moss, 2002, PNAS99 12415-20). The genomic BAC clone was 'rescued' back...... to infectious virus using a Fowlpox virus helper to supply transcriptional machinery. We apply here a similar approach to the attenuated strain Modified Vaccinia virus Ankara (MVA), now widely used as a safe non-replicating recombinant vaccine vector in mammals, including humans. Four apparently full......K counterselection to insert an antigen expression cassette lacking a tandem marker gene into the traditional thymidine kinase locus of MVA-BAC. MVA continues to feature prominently in clinical trials of recombinant vaccines against diseases such as HIV-AIDS, malaria and tuberculosis. Here we demonstrate in proof-of-concept...

  8. A bacterial artificial chromosome library for soybean PI 437654 and identification of clones associated with cyst nematode resistance.

    Science.gov (United States)

    Tomkins, J P; Mahalingam, R; Smith, H; Goicoechea, J L; Knap, H T; Wing, R A

    1999-09-01

    We have constructed a soybean bacterial artificial chromosome (BAC) library using the plant introduction (PI) 437654. The library contains 73 728 clones stored in 192 384-well microtiter plates. A random sampling of 230 BACs indicated an average insert size of 136 kb with a range of 20 to 325 kb, and less than 4% of the clones do not contain inserts. Ninety percent of BAC clones in the library have an average insert size greater than 100 kb. Based on a genome size of 1115 Mb, library coverage is 9 haploid genome equivalents. Screening the BAC library colony filters with cpDNA sequences showed that contamination of the genomic library with chloroplast clones was low (1.85%). Library screening with three genomic RFLP probes linked to soybean cyst nematode (SCN) resistance genes resulted in an average of 18 hits per probe (range 7 to 30). Two separate pools of forward and reverse suppression subtractive cDNAs obtained from SCN-infected and uninfected roots of PI437654 were hybridized to the BAC library filters. The 488 BACs identified from positive signals were fingerprinted and analyzed using FPC software (version 4.0) resulting in 85 different contigs. Contigs were grouped and analyzed in three categories: (1) contigs of BAC clones which hybridized to forward subtracted cDNAs, (2) contigs of BAC clones which hybridized to reverse subtracted cDNAs, and (3) contigs of BAC clones which hybridized to both forward and reverse subtracted cDNAs. This protocol provides an estimate of the number of genomic regions involved in early resistance response to a pathogenic attack.

  9. Cloning of a very virulent plus, 686 strain of Marek's disease virus as a bacterial artificial chromosome.

    Science.gov (United States)

    Reddy, Sanjay M; Sun, Aijun; Khan, Owais A; Lee, Lucy F; Lupiani, Blanca

    2013-06-01

    Bacterial artificial chromosome (BAC) vectors were first developed to facilitate propagation and manipulation of large DNA fragments. This technology was later used to clone full-length genomes of large DNA viruses to study viral gene function. Marek's disease virus (MDV) is a highly oncogenic herpesvirus that causes rapid induction of T-cell lymphomas in chickens. Based on the virus's ability to cause disease in vaccinated chickens, MDV strains are classified into pathotypes, with the most virulent strains belonging to the very virulent plus (vv+) pathotype. Here we report the construction of BAC clones of 686 (686-BAC), a vv+ strain of MDV. Transfection of DNA isolated from two independent clones into duck embryo fibroblasts resulted in recovery of infectious virus. Pathogenesis studies showed that the BAC-derived 686 viruses were more virulent than Md5, a vv strain of MDV. With the use of a two-step red-mediated mutagenesis process, both copies of viral interleukin 8 (vIL-8) were deleted from the MDV genome, showing that 686-BACs were amenable to mutagenesis techniques. The generation of BAC clones from a vv+ strain of MDV is a significant step toward understanding molecular basis of MDV pathogenesis.

  10. Development of new transformation-competent artificial chromosome vectors and rice genomic libraries for efficient gene cloning.

    Science.gov (United States)

    Liu, Yao-Guang; Liu, Hongmei; Chen, Letian; Qiu, Weihua; Zhang, Qunyu; Wu, Hao; Yang, Chunyi; Su, Jing; Wang, Zhonghua; Tian, Dongsheng; Mei, Mantong

    2002-01-09

    The transformation-competent artificial chromosome vector (TAC) system has been shown to be very useful for efficient gene isolation in Arabidopsis thaliana (Proc. Natl. Acad. Sci. USA 96 (1998) 6535). To adapt the vector system for gene isolation in crops, two new TAC vectors and rice genomic libraries were developed. The new vectors pYLTAC17 and pYLTAC27 use the Bar gene and Hpt gene driven by the rice Act1 promoter as the plant selectable markers, respectively, and are suitable for transformation of rice and other grasses. Two representative genomic libraries (I and II) of an Indica rice variety Minghui63, a fertility restorer line for hybrid rice, were constructed with pYLTAC17 using different size classes of partially digested DNA fragments. Library I and library II consisted of 34,560 and 1.2 x 10(5) clones, with average insert sizes of approximately 77 and 39 kb, respectively. The genome coverage of the libraries I and II was estimated to be about 5 and 11 haploid genome equivalents, respectively. Clones of the library I were stored individually in ninety 384-well plates, and those of the library II were collected as bulked pools each containing 30-50 clones and stored in eight 384-well plates. A number of probes were used to hybridize high-density colony filters of the library I prepared by an improved replicating method and each detected 2-9 positive clones. A method for rapid screening of the library II by pooled colony hybridization was developed. A TAC clone having an 80 kb rice DNA insert was successfully transferred into rice genome via Agrobacterium-mediated transformation. The new vectors and the genomic libraries should be useful for gene cloning and genetic engineering in rice and other crops.

  11. Sequential cloning of chromosomes

    Science.gov (United States)

    Lacks, S.A.

    1995-07-18

    A method for sequential cloning of chromosomal DNA of a target organism is disclosed. A first DNA segment homologous to the chromosomal DNA to be sequentially cloned is isolated. The first segment has a first restriction enzyme site on either side. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction (class IIS) enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes. 9 figs.

  12. Artifically inserting a reticuloendotheliosis virus long terminal repeat into a bacterial artificial chromosome clone of Marek's disease virus (MDV) alters expression of nearby MDV genes

    Science.gov (United States)

    The long terminal repeat (LTR) sequence of reticuloendotheliosis virus (REV) was inserted into the very virulent Marek’s disease virus (MDV) Md5 bacterial artificial chromosome clone. The insertion site was nearly identical to the REV LTR that was naturally inserted into the JM/102W strain of MDV fo...

  13. Next Generation Sequencing of Classical Swine Fever Virus and Border Disease virus cloned in Bacterial Artificial Chromosomes

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Höper, Dirk; Beer, martin;

    2012-01-01

    artificial chromosomes (BACs). From these BACs, RNA copies of the viral genomes can be transcribed in vitro and upon transfection of these RNAs into mammalian cells, autonomous replication of the viral genome occurs and infectious progeny can be rescued. However, we have observed that virus progeny can...

  14. A high-throughput strategy for screening of bacterial artificial chromosome libraries and anchoring of clones on a genetic map constructed with single nucleotide polymorphisms

    Directory of Open Access Journals (Sweden)

    Deal Karin R

    2009-01-01

    Full Text Available Abstract Background Current techniques of screening bacterial artificial chromosome (BAC libraries for molecular markers during the construction of physical maps are slow, laborious and often assign multiple BAC contigs to a single locus on a genetic map. These limitations are the principal impediment in the construction of physical maps of large eukaryotic genomes. It is hypothesized that this impediment can be overcome by screening multidimensional pools of BAC clones using the highly parallel Illumina GoldenGate™ assay. Results To test the efficacy of the Golden Gate assay in BAC library screening, multidimensional pools involving 302976 Aegilops tauschii BAC clones were genotyped for the presence/absence of specific gene sequences with multiplexed Illumina GoldenGate oligonucleotide assays previously used to place single nucleotide polymorphisms on an Ae. tauschii genetic map. Of 1384 allele-informative oligonucleotide assays, 87.6% successfully clustered BAC pools into those positive for a BAC clone harboring a specific gene locus and those negative for it. The location of the positive BAC clones within contigs assembled from 199190 fingerprinted Ae. tauschii BAC clones was used to evaluate the precision of anchoring of BAC clones and contigs on the Ae. tauschii genetic map. For 41 (95% assays, positive BAC clones were neighbors in single contigs. Those contigs could be unequivocally assigned to loci on the genetic map. For two (5% assays, positive clones were in two different contigs and the relationships of these contigs to loci on the Ae. tauschii genetic map were equivocal. Screening of BAC libraries with a simple five-dimensional BAC pooling strategy was evaluated and shown to allow direct detection of positive BAC clones without the need for manual deconvolution of BAC clone pools. Conclusion The highly parallel Illumina oligonucleotide assay is shown here to be an efficient tool for screening BAC libraries and a strategy for high

  15. Artificially inserting a reticuloendotheliosis virus long terminal repeat into a bacterial artificial chromosome clone of Marek's disease virus (MDV) alters expression of nearby MDV genes.

    Science.gov (United States)

    Kim, Taejoong; Mays, Jody; Fadly, Aly; Silva, Robert F

    2011-06-01

    Researchers reported that co-cultivating the JM/102W strain of Marek's disease virus (MDV) with reticuloendotheliosis virus (REV) resulted in an REV long terminal repeat (LTR) being inserted into the internal repeat short (IRS) region of JM/102W. When the resulting recombinant virus was serially passed in cell culture, the initial LTR was duplicated and a second LTR spontaneously appeared in the terminal repeat short (TRS) region of the MDV genome. The virus, designated RM1, was significantly attenuated but still induced severe bursal and thymic atrophy (Isfort et al. PNAS 89:991-995). To determine whether the altered phenotype was due solely to the LTR, we cloned the LTR from the RM1 IRS region and inserted it into the IRS region of a very virulent bacterial artificial clone (BAC) of the Md5 strain of MDV, which we designated rMd5-RM1-LTR. During blind passage in duck embryo fibroblast cultures, the initial LTR in the rMd5-RM1-LTR was also duplicated, with LTRs appearing in both IRS and TRS regions of the MDV genome. The inserted LTR sequences and transcripts associated with the MDV open reading frames MDV085, MDV086, SORF2, US1, and US10 were molecularly characterized. The parental Md5 BAC contains a family of transcripts of 3, 2, and 1 kb that all terminate at the end of the US10 gene. The rMd5-RM1-LTR and RM1 viruses both express an additional 4 kb transcript that originates in the LTR and also terminates after US10. Collectively, the data suggest that our engineered rMd5-RM1-LTR virus very closely resembles the RM1 virus in its structure and transcription patterns.

  16. A five-fold pig bacterial artificial chromosome library:a resource for positional cloning and physical mapping

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; LI Ning; ZHANG Ying; LIU Zhaoliang; GUO Li; WANG Xiaobo; FEI Jing; FENG Jidong; ZHAO Rui; HU Xiaoxiang

    2006-01-01

    A pig BAC library was constructed with genomic DNA from a male Erhualian pig. After partial digestion with Hind Ⅲ or BamH I the fragments obtained were cloned into the pBeloBAC11 vector. The library consists of 184320 clones which stored in 480pieces 384-well plates (20 plates per superpool). A two-step 4-dimension PCR screening system was established to screen the positive clones. An average insert size of 128 kb was estimated from 105 randomly isolated clones, which indicates that the library is more than five times of genomic coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 10single-copy genes were screened out and the positive clones were yielded between 1 and 8 with an average of 3.6. Positive superpools were obtained for 32 microsatellite markers selected from different regions of pig genome. The number of positive superpools for each marker varies from 1 to 9 with an average of 4.78. This BAC library provides an additional resource for pig physical mapping and gene identification.

  17. Bacterial Artificial Chromosome Mutagenesis Using Recombineering

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    Kumaran Narayanan

    2011-01-01

    Full Text Available Gene expression from bacterial artificial chromosome (BAC clones has been demonstrated to facilitate physiologically relevant levels compared to viral and nonviral cDNA vectors. BACs are large enough to transfer intact genes in their native chromosomal setting together with flanking regulatory elements to provide all the signals for correct spatiotemporal gene expression. Until recently, the use of BACs for functional studies has been limited because their large size has inherently presented a major obstacle for introducing modifications using conventional genetic engineering strategies. The development of in vivo homologous recombination strategies based on recombineering in E. coli has helped resolve this problem by enabling facile engineering of high molecular weight BAC DNA without dependence on suitably placed restriction enzymes or cloning steps. These techniques have considerably expanded the possibilities for studying functional genetics using BACs in vitro and in vivo.

  18. Large-scale cloning of human chromosome 2-specific yeast artificial chromosomes (YACs) using an interspersed repetitive sequences (IRS)-PCR approach.

    Science.gov (United States)

    Liu, J; Stanton, V P; Fujiwara, T M; Wang, J X; Rezonzew, R; Crumley, M J; Morgan, K; Gros, P; Housman, D; Schurr, E

    1995-03-20

    We report here an efficient approach to the establishment of extended YAC contigs on human chromosome 2 by using an interspersed repetitive sequences (IRS)-PCR-based screening strategy for YAC DNA pools. Genomic DNA was extracted from 1152 YAC pools comprised of 55,296 YACs mostly derived from the CEPH Mark I library. Alu-element-mediated PCR was performed for each pool, and amplification products were spotted on hybridization membranes (IRS filters). IRS probes for the screening of the IRS filters were obtained by Alu-element-mediated PCR. Of 708 distinct probes obtained from chromosome 2-specific somatic cell hybrids, 85% were successfully used for library screening. Similarly, 80% of 80 YAC walking probes were successfully used for library screening. Each probe detected an average of 6.6 YACs, which is in good agreement with the 7- to 7.5-fold genome coverage provided by the library. In a preliminary analysis, we have identified 188 YAC groups that are the basis for building contigs for chromosome 2. The coverage of the telomeric half of chromosome 2q was considered to be good since 31 of 34 microsatellites and 22 of 23 expressed sequence tags that were chosen from chromosome region 2q13-q37 were contained in a chromosome 2 YAC sublibrary generated by our experiments. We have identified a minimum of 1610 distinct chromosome 2-specific YACs, which will be a valuable asset for the physical mapping of the second largest human chromosome.

  19. Large-scale cloning of human chromosome 2-specific yeast artificial chromosomes (YACs) using an interspersed repetitive sequences (IRS)-PCR approach

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Rezonzew, R. [McGill Centre for the Study of Host Resistance, Montreal, Quebec (Canada)]|[McGill Univ., Montreal, Quebec (Canada); Stanton, V.P. Jr. [Massachusetts Institute of Technology, Cambridge, MA (United States)] [and others

    1995-03-20

    We report here an efficient approach to the establishment of extended YAC contigs on human chromosome 2 by using an interspersed repetitive sequences (IRS)-PCR-based screening strategy for YAC DNA pools. Genomic DNA was extracted from 1152 YAC pools comprised of 55,296 YACs mostly derived from the CEPH Mark I library. Alu-element-mediated PCR was performed for each pool, and amplification products were spotted on hybridization membranes (IRS filters). IRS probes for the screening of the IRS filters were obtained by Alu-element-mediated PCR. Of 708 distinct probes obtained from chromosome 2-specific somatic cell hybrids, 85% were successfully used for library screening. Similarly, 80% of 80 YAC walking probes were successfully used for library screening. Each probe detected an average of 6.6 YACs, which is in good agreement with the 7- to 7.5-fold genome coverage provided by the library. In a preliminary analysis, we have identified 188 YAC groups that are the basis for building contigs for chromosome 2. The coverage of the telomeric half of chromosome 2q was considered to be good since 31 of 34 microsatellites and 22 of 23 expressed sequence tags that were chosen from chromosome region 2q13-q37 were contained in a chromosome 2 YAC sublibrary generated by our experiments. We have identified a minimum of 1610 distinct chromosome 2-specific YACs, which will be a valuable asset for the physical mapping of the second largest human chromosome. 81 refs., 8 figs., 3 tabs.

  20. Insertion of reticuloendotheliosis virus long terminal repeat into a bacterial artificial chromosome clone of a very virulent Marek's disease virus alters its pathogenicity.

    Science.gov (United States)

    Mays, Jody K; Silva, Robert F; Kim, Taejoong; Fadly, Aly

    2012-01-01

    Co-cultivation of the JM/102W strain of Marek's disease virus (MDV) with reticuloendotheliosis virus (REV) resulted in the generation of a recombinant MDV containing the REV long terminal repeat (LTR) named the RM1 strain of MDV, a strain that was highly attenuated for oncogenicity but induced severe bursal and thymic atrophy. We hypothesize that the phenotypic changes were solely due to the LTR insertion. Furthermore, we hypothesize that insertion of REV LTR into an analogous location in a different MDV would result in a similar phenotypic change. To test these hypotheses, we inserted the REV LTR into a bacterial artificial chromosome (BAC) clone of a very virulent strain of MDV, Md5, and designated the virus rMd5-RM1-LTR. The rMd5-RM1-LTR virus and the rMd5 virus were passaged in duck embryo fibroblast cells for up to 40 passages before pathogenicity studies. Susceptible chickens were inoculated intra-abdominally at hatch with the viruses rMd5-RM1-LTR, rMd5 BAC parental virus, wild-type strain Md5, or strain RM1 of MDV. The rMd5-RM1-LTR virus was attenuated at cell culture passage 40, whereas the rMd5 BAC without RM1 LTR retained its pathogenicity at cell culture passage 40. Using polymerase chain analysis, the RM1 LTR insert was detected in MDV isolated from buffy coat cells collected from chickens inoculated with rMd5-RM1-LTR, but only at 1 week post inoculation. The data suggest that the presence of the RM1 LTR insert within MDV genome for 1 week post inoculation with virus at hatch is sufficient to cause a reduction in pathogenicity of strain Md5 of MDV.

  1. Construction of a yeast artificial chromosome contig encompassing the human acidic fibroblast growth factor (FGF1) gene: Toward the cloning of the ANLL/MDS tumor-suppressor gene

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Ing-Ming; Gilmore, E.C.; Liu, Yang; Payson, R.A. (Ohio State Univ., Columbus, OH (United States))

    1994-02-01

    The region surrounding the human acidic fibroblast growth factor (FGF1) locus on chromosome 5q31 is of particular interest since it represents a critical region consistently lost in acute nonlymphocytic leukemia (ANLL) or myelodysplastic syndrome (MDS) patients who have a demonstrable deletion of the distal portion of the long arm of chromosome 5. It is proposed that an ANLL/MDS leukemia suppressor gene resides on 5q31. The authors have previously shown that the gene is most likely localized between FGF1 and PDGFRB/CSF1R loci. The region has also been linked to at least four other genetic diseases, Treacher Collins syndrome, diastrophic dysplasia, limb-girdle muscular dystrophy, and an autosomal dominant deafness, by linkage analysis. Here, they describe yeast artificial chromosomes (YAC) spanning 450 kb around the FGF1 gene. Six YAC clones were isolated from a human YAC library and their restriction enzyme maps were determined. The overlap of the clones with each other and with FGF1 cosmid and phage clones was characterized. Three of the YAC clones were found to contain the entire FGF1 gene, which spans more than 100 kb. Proximal and distal ends of several of these YAC clones were isolated for further overlap cloning. The proximal ends of both Y2 and Y4 were localized to previously isolated FGF1 DNA by sequence analysis. The distal ends of these two clones also hybridized to a human-hamster hybrid containing chromosome 5 as the only human genetic material. These results suggest that these YAC clones represent colinear DNA around the FGF1 locus. None of the YAC clones were found to contain the CD 14 and GRL genes, the closest known proximal and distal markers (relative to the centromere) to the FGF1 gene, respectively. This contig is useful for the overlap cloning of the 5q31 region and for reverse genetic strategies for the isolation of disease genes in the region. 46 refs., 7 figs., 5 tabs.

  2. [Cashmere goat bacterial artificial chromosome recombination and cell transfection system].

    Science.gov (United States)

    Huang, Tian; Cao, Zhongyang; Yang, Yaohui; Cao, Gengsheng

    2016-03-01

    The Cashmere goat is mainly used to produce cashmere, which is very popular for its delicate fiber, luscious softness and natural excellent warm property. Keratin associated protein (KAP) and bone morphogenetic protein (BMP) of the Cashmere goat play an important role in the proliferation and development of cashmere fiber follicle cells. Bacterial artificial chromosome containing kap6.3, kap8.1 and bmp4 genes were used to increase the production and quality of Cashmere. First, we constructed bacterial artificial chromosomes by homology recombination. Then Tol2 transposon was inserted into bacterial artificial chromosomes that were then transfected into Cashmere goat fibroblasts by Amaxa Nucleofector technology according to the manufacture's instructions. We successfully constructed the BAC-Tol2 vectors containing target genes. Each vector contained egfp report gene with UBC promoter, Neomycin resistant gene for cell screening and two loxp elements for resistance removing after transfected into cells. The bacterial artificial chromosome-Tol2 vectors showed a high efficiency of transfection that can reach 1% to 6% with a highest efficiency of 10%. We also obtained Cashmere goat fibroblasts integrated exogenous genes (kap6.3, kap8.1 and bmp4) preparing for the clone of Cashmere goat in the future. Our research demonstrates that the insertion of Tol2 transposons into bacterial artificial chromosomes improves the transfection efficiency and accuracy of bacterial artificial chromosome error-free recombination.

  3. Artificial cloning of domestic animals.

    Science.gov (United States)

    Keefer, Carol L

    2015-07-21

    Domestic animals can be cloned using techniques such as embryo splitting and nuclear transfer to produce genetically identical individuals. Although embryo splitting is limited to the production of only a few identical individuals, nuclear transfer of donor nuclei into recipient oocytes, whose own nuclear DNA has been removed, can result in large numbers of identical individuals. Moreover, clones can be produced using donor cells from sterile animals, such as steers and geldings, and, unlike their genetic source, these clones are fertile. In reality, due to low efficiencies and the high costs of cloning domestic species, only a limited number of identical individuals are generally produced, and these clones are primarily used as breed stock. In addition to providing a means of rescuing and propagating valuable genetics, somatic cell nuclear transfer (SCNT) research has contributed knowledge that has led to the direct reprogramming of cells (e.g., to induce pluripotent stem cells) and a better understanding of epigenetic regulation during embryonic development. In this review, I provide a broad overview of the historical development of cloning in domestic animals, of its application to the propagation of livestock and transgenic animal production, and of its scientific promise for advancing basic research.

  4. Isolation and characterization of bovine herpesvirus 4 (BoHV-4 from a cow affected by post partum metritis and cloning of the genome as a bacterial artificial chromosome

    Directory of Open Access Journals (Sweden)

    Cavirani Sandro

    2009-08-01

    Full Text Available Abstract Background Bovine herpesvirus 4 (BoHV-4 is a gammaherpesvirus with a Worldwide distribution in cattle and is often isolated from the uterus of animals with postpartum metritis or pelvic inflammatory disease. Virus strain adaptation to an organ, tissue or cell type is an important issue for the pathogenesis of disease. To explore the mechanistic role of viral strain variation for uterine disease, the present study aimed to develop a tool enabling precise genetic discrimination between strains of BoHV-4 and to easily manipulate the viral genome. Methods A strain of BoHV-4 was isolated from the uterus of a persistently infected cow and designated BoHV-4-U. The authenticity of the isolate was confirmed by RFLP-PCR and sequencing using the TK and IE2 loci as genetic marker regions for the BoHV-4 genome. The isolated genome was cloned as a Bacterial Artificial Chromosome (BAC and manipulated through recombineering technology Results The BoHV-4-U genome was successfully cloned as a BAC, and the stability of the pBAC-BoHV-4-U clone was confirmed over twenty passages, with viral growth similar to the wild type virus. The feasibility of using BoHV-4-U for mutagenesis was demonstrated using the BAC recombineering system. Conclusion The analysis of genome strain variation is a key method for investigating genes associated with disease. A resource for dissection of the interactions between BoHV-4 and host endometrial cells was generated by cloning the genome of BoHV-4 as a BAC.

  5. Human Chromosome 21: Mapping of the chromosomes and cloning of cDNAs

    Energy Technology Data Exchange (ETDEWEB)

    Antonarakis, S.E.

    1991-09-01

    The objective of the research funded by DOE grant DE-FG02-89ER60857 from 6/15/89 to 8/31/91 was to contribute to the physical mapping of human chromosome 21 (HC21) by cloning large fragments of DNA into Yeast Artificial Chromosomes (YACs) and identify YACs that map on HC21. A total of 54 sequence tagged sites (STS) have been developed and mapped in our laboratory to HC21 and can be used as initial reference points for YAC identification and construction of overlapping clones. A small YAC library was constructed which is HC21 specific. DNA from somatic cell hybrid WAV17 or from flow-sorted HC21 was partially digested with EcoRI, ligated into vectors PJS97, PJS98, and YACs have been obtained with average size insert of more than 300 kb. This library has been deposited in D. Patterson's lab for the Joint YAC screening effort. Additional YAC libraries from ICI Pharmaceuticals or from Los Alamos National Laboratories have been screened with several STS and positive YACs have been identified. Work in progress includes screening of YAC libraries in order to construct overlapping clones, characterization of the cloning ends of YACs, characterization of additional STS and cloning of HC21 specific cDNAs. 15 refs., 2 figs., 5 tabs.

  6. Construction and characterization of a Schistosoma mansoni bacterial artificial chromosome library.

    Science.gov (United States)

    Le Paslier, M C; Pierce, R J; Merlin, F; Hirai, H; Wu, W; Williams, D L; Johnston, D; LoVerde, P T; Le Paslier, D

    2000-04-15

    A bacterial artificial chromosome (BAC) library has been established from genomic DNA isolated from the trematode parasite of human, Schistosoma mansoni. This library consists of more than 21,000 recombinant clones carrying inserts in the pBeloBAC11 vector. The mean insert size was 100 kb, representing an approximate 7.95-fold genome coverage. Library screening with eight chromosome-specific or single-copy gene probes yielded between 1 and 9 positive clones, and none of those tested was absent from the library. End sequences were obtained for 93 randomly selected clones, and 37 showed sequence identity to S. mansoni sequences (ESTs, genes, or repetitive sequences). A preliminary analysis by fluorescence in situ hybridization localized 8 clones on schistosome chromosomes 1 (2 clones), 2, 3, 5, Z, and W (3 clones). This library provides a new resource for the physical mapping and sequencing of the genome of this important human pathogen.

  7. Construction of human artificial chromosome vectors by recombineering.

    Science.gov (United States)

    Kotzamanis, George; Cheung, Wing; Abdulrazzak, Hassan; Perez-Luz, Sara; Howe, Steven; Cooke, Howard; Huxley, Clare

    2005-05-23

    Human artificial chromosomes (HACs) can be formed de novo by transfection of large fragments of cloned alphoid DNA into human HT1080 cells in tissue culture. In order to generate HACs carrying a gene of interest, one can either co-transfect the alphoid DNA and the gene of interest, or one can clone both into a single vector prior to transfection. Here we describe linking approximately 70 kb of alphoid DNA onto a 156-kb BAC carrying the human HPRT gene using Red homologous recombination in the EL350 Escherichia coli host [Lee et al., Genomics 73 (2001) 56-65]. A selectable marker and EGFP marker were then added by loxP/Cre recombination using the arabinose inducible cre gene in the EL350 bacteria. The final construct generates minichromosomes in HT1080 cells and the HPRT gene is expressed. The retrofitting vector can be used to add the approximately 70 kb of alphoid DNA to any BAC carrying a gene of interest to generate a HAC vector. The method can also be used to link any unrelated BAC or PAC insert onto another BAC clone. The EL350 bacteria are an excellent host for building up complex vectors by a combination of homologous and loxP/Cre recombination.

  8. A 6. 5-Mb yeast artificial chromosome contig incorporating 33 DNA markers on the human X chromosome at Xq22

    Energy Technology Data Exchange (ETDEWEB)

    Vetrie, D.; Kendall, E.; Coffey, A.; Hassock, S.; Collins, J.; Todd, C.; Bobrow, M.; Bentley, D.R. (Paediatric Research Unit, London (United Kingdom)); Lehrach, H. (Imperial Cancer Research Fund, London (United Kingdom)); Harris, A. (John Radcliffe Hospital, Oxford (United Kingdom))

    1994-01-01

    The Xq22 region of the human X chromosome contains genes for a number of inherited disorders. Sixty-nine yeast artificial chromosome clones have been isolated and assembled into a 6.5-Mb contig that contains 33 DNA markers localized to this region. This contig extends distally from DXS366 to beyond DXS87 and includes the genes involved in X-linked agammaglobulinemia (btk), Fabry disease (GLA), and Pelizaeus-Merzbacher disease (PLP). The order of markers in this contig is consistent with the known genetic and physical mapping information of Xq22. This cloned material provides a source from which to isolate other genes located in this part of the X chromosome. 45 refs., 2 figs., 2 tabs.

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

    Directory of Open Access Journals (Sweden)

    Doležel Jaroslav

    2010-02-01

    Full Text Available Abstract 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

  10. Strategies for cloning and manipulating natural and synthetic chromosomes.

    Science.gov (United States)

    Karas, Bogumil J; Suzuki, Yo; Weyman, Philip D

    2015-02-01

    Advances in synthetic biology methods to assemble and edit DNA are enabling genome engineering at a previously impracticable scale and scope. The synthesis of the Mycoplasma mycoides genome followed by its transplantation to convert a related cell into M. mycoides has transformed strain engineering. This approach exemplifies the combination of newly emerging chromosome-scale genome editing strategies that can be defined in three main steps: (1) chromosome acquisition into a microbial engineering platform, (2) alteration and improvement of the acquired chromosome, and (3) installation of the modified chromosome into the original or alternative organism. In this review, we outline recent progress in methods for acquiring chromosomes and chromosome-scale DNA molecules in the workhorse organisms Bacillus subtilis, Escherichia coli, and Saccharomyces cerevisiae. We present overviews of important genetic strategies and tools for each of the three organisms, point out their respective strengths and weaknesses, and highlight how the host systems can be used in combination to facilitate chromosome assembly or engineering. Finally, we highlight efforts for the installation of the cloned/altered chromosomes or fragments into the target organism and present remaining challenges in expanding this powerful experimental approach to a wider range of target organisms.

  11. Delineating Rearrangements in Single Yeast Artificial Chromosomes by Quantitative DNA Fiber Mapping

    Energy Technology Data Exchange (ETDEWEB)

    Weier, Heinz-Ulrich G.; Greulich-Bode, Karin M.; Wu, Jenny; Duell, Thomas

    2009-09-18

    Cloning of large chunks of human genomic DNA in recombinant systems such as yeast or bacterial artificial chromosomes has greatly facilitated the construction of physical maps, the positional cloning of disease genes or the preparation of patient-specific DNA probes for diagnostic purposes. For this process to work efficiently, the DNA cloning process and subsequent clone propagation need to maintain stable inserts that are neither deleted nor otherwise rearranged. Some regions of the human genome; however, appear to have a higher propensity than others to rearrange in any host system. Thus, techniques to detect and accurately characterize such rearrangements need to be developed. We developed a technique termed 'Quantitative DNA Fiber Mapping (QDFM)' that allows accurate tagging of sequence elements of interest with near kilobase accuracy and optimized it for delineation of rearrangements in recombinant DNA clones. This paper demonstrates the power of this microscopic approach by investigating YAC rearrangements. In our examples, high-resolution physical maps for regions within the immunoglobulin lambda variant gene cluster were constructed for three different YAC clones carrying deletions of 95 kb and more. Rearrangements within YACs could be demonstrated unambiguously by pairwise mapping of cosmids along YAC DNA molecules. When coverage by YAC clones was not available, distances between cosmid clones were estimated by hybridization of cosmids onto DNA fibers prepared from human genomic DNA. In addition, the QDFM technology provides essential information about clone stability facilitating closure of the maps of the human genome as well as those of model organisms.

  12. Construction and characterization of human chromosome 2-specific cosmid, fosmid, and PAC clone libraries

    Energy Technology Data Exchange (ETDEWEB)

    Gingrich, J.C.; Boehrer, D.M.; Garnes, J.A. [Lawrence Livermore National Lab., CA (United States)] [and others

    1996-02-15

    This article discusses the construction and characterization of three human chromosome 2-specific clone libraries. A chromosome 2-specific PAC library was also constructed from a hybrid cell line. The chromosome 2 coverage of each of the three libraries was further determined by PCR screening clone pools with 82 chromosome 2-specific STSs. 47 refs., 3 figs., 1 tab.

  13. Construction of bacterial artificial chromosome libraries for Zhikong Scallop Chlamys farreri

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yang; ZHANG Xiaojun; Chantel F.SCHEURING; ZHANG Hongbin; LI Fuhua; XIANG Jianhai

    2008-01-01

    Two Large-insert genomic bacterial artificial chromosome (BAC) libraries of Zhikong scallop Chlamys farreri were constructed to promote our genetic and genomic research.High-quality megabase-sized DNA was isolated from the adductor muscle of the scallop and partially digested by BamH I and Mbo I,respectively.The BamH I library consisted of 53760 clones while the Mbo I library consisted of 7680 clones.Approximately 96% of the clones in BamH I library contained nuclear DNA inserts in average size of 100 kb,providing a coverage of 5.3 haploid genome equivalents.Similarly,the Mbo I library with an average insert of 145 kb and no insert-empty clones,thus providing a genome coverage of 1.1 haploid genome equivalents.

  14. Molecular cloning and chromosome assignment of murine N-ras.

    OpenAIRE

    Ryan, J.; Hart, C P; Ruddle, F H

    1984-01-01

    The murine N-ras gene was cloned by screening an EMBL-3 recombinant phage library with a human N-ras specific probe. Hybridization of two separate unique sequence N-ras probes, isolated from the 5' and 3' flanking sequences of the murine gene, to a mouse-Chinese hamster hybrid mapping panel assigns the N-ras locus to mouse chromosome three.

  15. Construction and characterization of the transformation-competent artificial chromosome (TAC) libraries of Leymus multicaulis

    Institute of Scientific and Technical Information of China (English)

    XU YueYu; ZHOU YuLei; SONG LinLin; ZHANG Yan; ZHAO MaoLin

    2008-01-01

    Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in plants. In order to clone genes highly tolerant to barley yellow dwarf virus (BYDV), Aphids, drought and salt from Leymus multicaulis, the two TAC genomic libraries Ⅰ and Ⅱ were constructed in vector pYLTAC17 and pYLTAC747H/sacB, which contain about 165000 and 236000 recombinant clones sepa-rately. The genome coverage of the two libraries was totally estimated to be about 3-5 haploid genome equivalents, as size selection of genomic DNA fragments was approximately from 9 to 300 kb. Clones of the genomic libraries were collected as bulked pools each containing 500 clones or so, stored in twelve 96-deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3×3 pattern using a GeneTACTM G3 arraying robot after being transferred manually into three 384-well plates. Meanwhile 2501 and 2890 clones of Library in pYLTAC17 and in pYLTAC747H/sacB were stored individually in fourteen 384-well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6×6 pattern after a replication of plates. Nineteen positive clones were detected by using the probe glutahione reductase gene of L. Multicaulis. TAC libraries constructed here can be used to isolate genomic clones containing target genes, and to carry out genome walking for positional cloning. Once the target TAC clones were isolated, they could be immediately transferred into plant genomes with the Agrobacterium system.

  16. Construction and characterization of the transformation-competent artificial chromosome(TAC)libraries of Leymus multicaulis

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in plants.In order to clone genes highly tolerant to barley yellow dwarf virus(BYDV),Aphids,drought and salt from Leymus multicaulis,the two TAC genomic libraries I and II were constructed in vector pYLTAC17 and pYLTAC747H/sacB,which contain about 165000 and 236000 recombinant clones sepa-rately.The genome coverage of the two libraries was totally estimated to be about 3―5 haploid genome equivalents,as size selection of genomic DNA fragments was approximately from 9 to 300 kb.Clones of the genomic libraries were collected as bulked pools each containing 500 clones or so,stored in twelve 96-deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3×3 pattern using a GeneTAC?G3 arraying robot after being transferred manually into three 384-well plates.Meanwhile 2501 and 2890 clones of Library in pYLTAC17 and in pYLTAC747H/sacB were stored individually in fourteen 384-well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6×6 pattern after a replication of plates.Nineteen positive clones were detected by using the probe glutahione reductase gene of L.multicaulis.TAC libraries constructed here can be used to isolate genomic clones containing target genes,and to carry out genome walking for positional cloning.Once the target TAC clones were isolated,they could be immediately transferred into plant genomes with the Agrobacterium system.

  17. Positional cloning of disease genes on chromosome 16

    Energy Technology Data Exchange (ETDEWEB)

    Doggett, N. [Los Alamos National Lab., NM (United States); Bruening, M. [Leiden Univ. (Netherlands); Callen, D. [Adelaide Women`s and Children`s Hospital, North Adelaide, South Australia (Australia); Gardiner, M. [University Coll., London (United Kingdom); Lerner, T. [Massachusetts General Hospital, Boston, MA (United States)

    1996-04-01

    The project seeks to elucidate the molecular basis of an important genetic disease (Batten`s disease) by molecular cloning of the affected gene by utilizing an overlapping clone map of chromosome 16. Batten disease (also known as juvenile neuronal ceroid lipofuscinosis) is a recessively inherited neurodegenerative disorder of childhood characterized by progressive loss of vision, seizures, and psychomoter disturbances. The Batten disease gene was genetically mapped to the chromosome region 16p 12.1 in close linkage with the genetic markers D16S299 and D16S298. Exon amplification of a cosmid containing D16S298 yielded a candidate gene that was disrupted by a 1 kb genomic deletion in all patients containing the most common haplotype for the disease. Two separate deletions and a point mutation altering a splice site in three unrelated families have confirmed the gene as the Batten disease gene. The disease gene encodes a novel 438 amino acid membrane binding protein of unknown function.

  18. Human estrogen sulfotransferase gene (STE): Cloning, structure, and chromosomal localization

    Energy Technology Data Exchange (ETDEWEB)

    Her, Chengtao; Aksoy, I.A.; Weinshilboum, M. [Mayo Foundation, Rochester, MI (United States)] [and others

    1995-09-01

    Sulfation is an important pathway in the metabolism of estrogens. We recently cloned a human liver estrogen sulfotransferase (EST) cDNA. We have now determined the structure and chromosomal localization of the EST gene, STE, as a step toward molecular genetic studies of the regulation of EST in humans. STE spans approximately 20 kb and consists of 8 exons, ranging in length from 95 to 181 bp. The locations of most exon-intron splice junctions within STE are identical to those found in a human phenol ST (PST) gene, STM, and in a rat PST gene. In addition, the locations of five STE introns are also conserved in the human dehydroepiandrosterone (DBEA) ST gene, STD. The 5{prime} flanking region of STE contains one CCAAT and two TATA sequences. The location of one of the TATA box elements is in excellent agreement with the site of transcription initiation as determined by 5{prime}-rapid amplification of cDNA ends. STE was mapped to human chromosome 4q13.1 by fluorescence in situ hybridization. Cloning and structural characterization of STE will now make it possible to study potential molecular genetic mechanisms involved in the regulation of EST in human tissues. 50 refs., 6 figs., 1 tab.

  19. Construction of a Bacterial Artificial Chromosome Library of TM-1, a Standard Line for Genetics and Genomics in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    Yan Hu; Wang-Zhen Guo; Tian-Zhen Zhang

    2009-01-01

    A bacterial artificial chromosome (BAC) library was constructed for Gossyplum hirsutum acc. TM-1, a genetic and genomic standard line for Upland cotton. The library consists of 147 456 clones with an average insert size of 122.8 kb ranging from 97 to 240 kb. About 96.0% of the clones have inserts over 100 kb. Therefore, this library represents theoretically 7.4 haploid genome equivalents based on an AD genome size of 2 425 Mb. Clones were stored in 384 384- well plates and arrayed into multiplex pools for rapid and reliable library screening. BAC screening was carded out by four-round polymerase chain reactions using 23 simple sequence repeats (SSR) markers, three sequence-related amplified polymorphism markers and one pair of pdmere for a gene associated with fiber development to test the quality of the library. Correspondingly, in total 92 positive BAC clones were Identified with an average four positive clones per SSR marker, ranging from one to eight hits. Additionally, since these SSR markers have been localized to chromosome 12 (A12) and 26 (D12) according to the genetic map, these BAC clonee are expected to serve as seeds for the physical mapping of these two homologous chromosomes, sequentially map-based cloning of quantitative trait loci or genes associated with Important agronomic traits.

  20. Integrative bacterial artificial chromosomes for DNA integration into the Bacillus subtilis chromosome.

    Science.gov (United States)

    Juhas, Mario; Ajioka, James W

    2016-06-01

    Bacillus subtilis is a well-characterized model bacterium frequently used for a number of biotechnology and synthetic biology applications. Novel strategies combining the advantages of B. subtilis with the DNA assembly and editing tools of Escherichia coli are crucial for B. subtilis engineering efforts. We combined Gibson Assembly and λ red recombineering in E. coli with RecA-mediated homologous recombination in B. subtilis for bacterial artificial chromosome-mediated DNA integration into the well-characterized amyE target locus of the B. subtilis chromosome. The engineered integrative bacterial artificial chromosome iBAC(cav) can accept any DNA fragment for integration into B. subtilis chromosome and allows rapid selection of transformants by B. subtilis-specific antibiotic resistance and the yellow fluorescent protein (mVenus) expression. We used the developed iBAC(cav)-mediated system to integrate 10kb DNA fragment from E. coli K12 MG1655 into B. subtilis chromosome. iBAC(cav)-mediated chromosomal integration approach will facilitate rational design of synthetic biology applications in B. subtilis.

  1. Preparation of high molecular weight gDNA and bacterial artificial chromosome (BAC) libraries in plants.

    Science.gov (United States)

    Biradar, Siddanagouda S; Nie, Xiaojun; Feng, Kewei; Weining, Song

    2014-01-01

    Bacterial artificial chromosome (BAC) libraries are extremely valuable large-insert DNA libraries for physical mapping, positional cloning, comparative genomic analysis, complete genome sequencing, and evolutionary studies. Due to their stability and relative simplicity BAC libraries are most preferred over other approaches for cloning large genomic DNA fragments for large-insert libraries. Isolation of intact high molecular weight (HMW) DNA is a critical step underlying the success of large-insert genomic DNA library construction. It requires the isolation of purified nuclei, embedding them into LMP agarose plugs, restriction digestion of the plugs, and quite often size selection using PFGE and electro-elution of insert DNA. The construction of BAC libraries is complex and challenging for most molecular laboratories. To facilitate the construction of BAC libraries, we present a step-by-step protocol for isolation of HMW DNA and construction of plant BAC libraries.

  2. Construction and characterization of bacterial artificial chromosomes (BACs) containing herpes simplex virus full-length genomes.

    Science.gov (United States)

    Nagel, Claus-Henning; Pohlmann, Anja; Sodeik, Beate

    2014-01-01

    Bacterial artificial chromosomes (BACs) are suitable vectors not only to maintain the large genomes of herpesviruses in Escherichia coli but also to enable the traceless introduction of any mutation using modern tools of bacterial genetics. To clone a herpes simplex virus genome, a BAC replication origin is first introduced into the viral genome by homologous recombination in eukaryotic host cells. As part of their nuclear replication cycle, genomes of herpesviruses circularize and these replication intermediates are then used to transform bacteria. After cloning, the integrity of the recombinant viral genomes is confirmed by restriction length polymorphism analysis and sequencing. The BACs may then be used to design virus mutants. Upon transfection into eukaryotic cells new herpesvirus strains harboring the desired mutations can be recovered and used for experiments in cultured cells as well as in animal infection models.

  3. Construction of bacterial artificial chromosome libraries for the Lake Malawi cichlid (Metriaclima zebra), and the blind cavefish (Astyanax mexicanus).

    Science.gov (United States)

    Di Palma, Federica; Kidd, Celeste; Borowsky, Richard; Kocher, Thomas D

    2007-01-01

    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 bacterial artificial chromosome 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 cichlids which have evolved over the last one million years in Lake Malawi, East Africa. The Mexican tetra, Astyanax mexicanus, is well known for adaptations related to the recent evolution of blind cave-dwelling forms. Clones and high-density filters for each library are available to the scientific community through the Hubbard Center for Genome Studies.

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

    Energy Technology Data Exchange (ETDEWEB)

    Jean-Michael H. Vos

    1999-12-09

    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.

  5. Human artificial chromosome vectors meet stem cells: new prospects for gene delivery.

    Science.gov (United States)

    Ren, Xianying; Tahimic, Candice Ginn T; Katoh, Motonobu; Kurimasa, Akihiro; Inoue, Toshiaki; Oshimura, Mitsuo

    2006-01-01

    The recent emergence of stem cell-based tissue engineering has now opened up new venues for gene therapy. The task now is to develop safe and effective vectors that can deliver therapeutic genes into specific stem cell lines and maintain long-term regulated expression of these genes. Human artificial chromosomes (HACs) possess several characteristics that require gene therapy vectors, including a stable episomal maintenance, and the capacity for large gene inserts. HACs can also carry genomic loci with regulatory elements, thus allowing for the expression of transgenes in a genetic environment similar to the chromosome. Currently, HACs are constructed by a two prone approaches. Using a top-down strategy, HACs can be generated from fragmenting endogenous chromosomes. By a bottom-up strategy, HACs can be created de novo from cloned chromosomal components using chromosome engineering. This review describes the current advances in developing HACs, with the main focus on their applications and potential value in gene delivery, such as HAC-mediated gene expression in embryonic, adult stem cells, and transgenic animals.

  6. DNA sequences and composition from 12 BAC clones-derived MUSB SSR markers mapped to cotton (Gossypium Hirsutum L. x G. Barbadense L.)chromosomes 11 and 21

    Science.gov (United States)

    To discover resistance (R) and/or pathogen-induced (PR) genes involved in disease response, 12 bacterial artificial chromosome (BAC) clones from cv. Acala Maxxa (G. hirsutum) were sequenced at the Clemson University, Genomics Institute, Clemson, SC. These BACs derived MUSB single sequence repeat (SS...

  7. HACking the centromere chromatin code: insights from human artificial chromosomes.

    Science.gov (United States)

    Bergmann, Jan H; Martins, Nuno M C; Larionov, Vladimir; Masumoto, Hiroshi; Earnshaw, William C

    2012-07-01

    The centromere is a specialized chromosomal region that serves as the assembly site of the kinetochore. At the centromere, CENP-A nucleosomes form part of a chromatin landscape termed centrochromatin. This chromatin environment conveys epigenetic marks regulating kinetochore formation. Recent work sheds light on the intricate relationship between centrochromatin state, the CENP-A assembly pathway and the maintenance of centromere function. Here, we review the emerging picture of how chromatin affects mammalian kinetochore formation. We place particular emphasis on data obtained from Human Artificial Chromosome (HAC) biology and the targeted engineering of centrochromatin using synthetic HACs. We discuss implications of these findings, which indicate that a delicate balance of histone modifications and chromatin state dictates both de novo centromere formation and the maintenance of centromere identity in dividing cell populations.

  8. [CHL15--a new gene controlling the replication of chromosomes in saccharomycetes yeast: cloning, physical mapping, sequencing, and sequence analysis].

    Science.gov (United States)

    Kuprina, N Iu; Krol', E S; Koriabin, M Iu; Shestopalov, B V; Bliskovskiĭ, V V; Bannikov, V M; Gizatullin, R Z; Kirillov, A V; Kravtsov, V Iu; Zakhar'ev, V M

    1993-01-01

    We have analyzed the CHL15 gene, earlier identified in a screen for yeast mutants with increased loss of chromosome III and artificial circular and linear chromosomes in mitosis. Mutations in the CHL15 gene lead to a 100-fold increase in the rate of chromosome III loss per cell division and a 200-fold increase in the rate of marker homozygosis on this chromosome by mitotic recombination. Analysis of segregation of artificial circular minichromosome and artificially generated nonessential marker chromosome fragment indicated that sister chromatid loss (1:0 segregation) is a main reason of chromosome destabilization in the chl15-1 mutant. A genomic clone of CHL15 was isolated and used to map its physical position on chromosome XVI. Nucleotide sequence analysis of CHL15 revealed a 2.8-kb open reading frame with a 105-kD predicted protein sequence. At the N-terminal region of the protein sequences potentially able to form DNA-binding domains defined as zinc-fingers were found. The C-terminal region of the predicted protein displayed a similarity to sequence of regulatory proteins known as the helix-loop-helix (HLH) proteins. Data on partial deletion analysis suggest that the HLH domain is essential for the function of the CHL15 gene product. Analysis of the upstream untranslated region of CHL15 revealed the presence of the hexamer element, ACGCGT (an MluI restriction site) controlling both the periodic expression and coordinate regulation of the DNA synthesis genes in budding yeast. Deletion in the RAD52 gene, the product of which is involved in double-strand break/recombination repair and replication, leads to a considerable decrease in the growth rate of the chl15 mutant. We suggest that CHL15 is a new DNA synthesis gene in the yeast Saccharomyces cerevisiae.

  9. Construction of male and female PAC genomic libraries suitable for identification of Y-chromosome-specific clones from the liverwort, Marchantia polymorpha.

    Science.gov (United States)

    Okada, S; Fujisawa, M; Sone, T; Nakayama, S; Nishiyama, R; Takenaka, M; Yamaoka, S; Sakaida, M; Kono, K; Takahama, M; Yamato, K T; Fukuzawa, H; Brennicke, A; Ohyama, K

    2000-11-01

    Unlike higher plants, the dioecious liverwort, Marchantia polymorpha, has uniquely small sex chromosomes, with X chromosomes present only in female gametophytes and Y chromosomes only in male gametophytes. We have constructed respective genomic libraries for male and female plantlets using a P1-derived artificial chromosome (pCYPAC2). With an average insert size of approximately 90 kb, each PAC library is estimated to cover the entire genome with a probability of more than 99.9%. Male-specific PAC clones were screened for by differential hybridization using male and female genomic DNAs as separate probes. Seventy male-specific PAC clones were identified. The male specificity of one of the clones, pMM4G7, was verified by Southern hybridization and PCR analysis. This clone was indeed located on the Y chromosome as verified by fluorescence in situ hybridization (FISH). This result shows that the Y chromosome contains unique sequences that are not present either on the X chromosome or any of the autosomes. Thus, the respective male and female libraries for M. polymorpha offer an opportunity to identify key genes involved in the process of sex differentiation and this unique system of sex determination.

  10. Cloning of Bovine herpesvirus type 1 and type 5 as infectious bacterial artifical chromosomes

    Directory of Open Access Journals (Sweden)

    Ackermann Mathias

    2009-10-01

    Full Text Available Abstract Background Bovine herpesviruses type 1 (BoHV1 and type 5 (BoHV5 are two closely related pathogens of cattle. The identity of the two viruses on the amino acid level averages 82%. Despite their high antigenetic similarities the two pathogens induce distinctive clinical signs. BoHV1 causes respiratory and genital tract infections while BoHV5 leads to severe encephalitis in calves. Findings The viral genomes of BoHV1 and BoHV5 were cloned as infectious bacterial artificial chromosomes (BACs. First, recombinant viruses carrying the genetic elements for propagation in bacteria were generated. Second, DNA from these recombinant viruses were transferred into prokaryotic cells. Third, DNA from these bacteria were transferred into eukaryotic cells. Progeny viruses from BAC transfections showed similar kinetics as their corresponding wild types. Conclusion The two viral genomes of BoHV1 and BoHV5 cloned as BACs are accessible to the tools of bacterial genetics. The ability to easily manipulate the viral genomes on a molecular level in future experiments will lead to a better understanding of the difference in pathogenesis induced by these two closely related bovine herpesviruses.

  11. Aquifer parameter identification by the best chromosome clone plus younger generation chromosome prepotency genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    LI Jing-sheng; LI Kai; YAO Lei-hua

    2005-01-01

    This paper developed an improved combinatorial method called the best chromosome clone plus younger generation chromosome prepotency genetic algorithm (BCC-YGCP-GA) to evaluate aquifer parameters. This method is based on a decimal simple genetic algorithm (SGA). A synthetic example for unsteady-state flow in a two-dimensional, inhomogeneous, confined aquifer containing three hydraulically distinct zones, is used to develop data to test the model. The simulation utilizes SGA and BCC-YGCP-GA coupled to the finite element method to identify the mean zonal hydraulic conductivities, and storage coefficients of the three-compartment model. For this geometrically simple model, used as a prototype of more complex systems, the SGA does not reach convergence within 100 generations. Conversely, the convergence rate of the BCC-YGCD-GA model is very fast. The objective function value calculated by BCC-YGCD-GA is reduced to 1/1 000th of the starting value within 100 generations,and the hydraulic conductivity and storage of three zones are within a few percent of the "true" values of the ideal model, highlighting the power of the method for aquifer parameterization.

  12. Construction of a llama bacterial artificial chromosome library with approximately 9-fold genome equivalent coverage.

    Science.gov (United States)

    Airmet, K W; Hinckley, J D; Tree, L T; Moss, M; Blumell, S; Ulicny, K; Gustafson, A K; Weed, M; Theodosis, R; Lehnardt, M; Genho, J; Stevens, M R; Kooyman, D L

    2012-01-01

    The Ilama is an important agricultural livestock in much of South America. The llama is increasing in popularity in the United States as a companion animal. Little work has been done to improve llama production using modern technology. A paucity of information is available regarding the llama genome. We report the construction of a llama bacterial artificial chromosome (BAC) library of about 196,224 clones in the vector pECBAC1. Using flow cytometry and bovine, human, mouse, and chicken as controls, we determined the llama genome size to be 2.4 × 10⁹ bp. The average insert size of the library is 137.8 kb corresponding to approximately 9-fold genome coverage. Further studies are needed to further characterize the library and llama genome. We anticipate that this new library will help facilitate future genomic studies in the llama.

  13. Mapping and ordered cloning of the human X chromosome

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, C.T.; Nelson, D.L.

    1992-12-01

    Progress is reported on gathering X chromosome specific libraries and integrating those with the library produced in this project. Further studies on understanding Fragile X Syndrome and other hereditary diseases related to the X chromosome are described. (DT)

  14. Isolation and comparative mapping of a human chromosome 20-specific alpha-satellite DNA clone.

    Science.gov (United States)

    Baldini, A; Archidiacono, N; Carbone, R; Bolino, A; Shridhar, V; Miller, O J; Miller, D A; Ward, D C; Rocchi, M

    1992-01-01

    We have isolated and characterized a human genomic DNA clone (PZ20, locus D20Z2) that identifies, under high-stringency hybridization conditions, an alphoid DNA subset specific for chromosome 20. The specificity was determined using fluorescence in situ hybridization. Sequence analysis confirmed our previously reported data on the great similarity between the chromosome 20 and chromosome 2 alphoid subsets. Comparative mapping of pZ20 on chimpanzee and gorilla chromosomes, also performed under high-stringency conditions, indicates that the alphoid subset has ancestral sequences on chimpanzee chromosome 11 and gorilla chromosome 19. However, no hybridization was observed to chromosomes 21 in the great apes, the homolog of human chromosome 20.

  15. Rapid cloning and bioinformatic analysis of spinach Y chromosome-specific EST sequences

    Indian Academy of Sciences (India)

    Chuan-Liang Deng; Wei-Li Zhang; Ying Cao; Shao-Jing Wang; Shu-Fen Li; Wu-Jun Gao; Long-Dou Lu

    2015-12-01

    The genome of spinach single chromosome complement is about 1000 Mbp, which is the model material to study the molecular mechanisms of plant sex differentiation. The cytological study showed that the biggest spinach chromosome (chromosome 1) was taken as spinach sex chromosome. It had three alleles of sex-related , m and . Many researchers have been trying to clone the sex-determining genes and investigated the molecular mechanism of spinach sex differentiation. However, there are no successful cloned reports about these genes. A new technology combining chromosome microdissection with hybridization-specific amplification (HSA) was adopted. The spinach Y chromosome degenerate oligonucleotide primed-PCR (DOP-PCR) products were hybridized with cDNA of the male spinach flowers in florescence. The female spinach genome was taken as blocker and cDNA library specifically expressed in Y chromosome was constructed. Moreover, expressed sequence tag (EST) sequences in cDNA library were cloned, sequenced and bioinformatics was analysed. There were 63 valid EST sequences obtained in this study. The fragment size was between 53 and 486 bp. BLASTn homologous alignment indicated that 12 EST sequences had homologous sequences of nucleic acids, the rest were new sequences. BLASTx homologous alignment indicated that 16 EST sequences had homologous protein-encoding nucleic acid sequence. The spinach Y chromosome-specific EST sequences laid the foundation for cloning the functional genes, specifically expressed in spinach Y chromosome. Meanwhile, the establishment of the technology system in the research provided a reference for rapid cloning of other biological sex chromosome-specific EST sequences.

  16. cDNA cloning, tissue distribution, and chromosomal localization of myelodysplasia/Myeloid Leukemia Factor 2 (MLF2)

    Energy Technology Data Exchange (ETDEWEB)

    Kuefer, M.U.; Valentine, V.; Behm, F.G. [St. Jude Children`s Research Hospital, Memphis, TN (United States)] [and others

    1996-07-15

    A fusion gene between nucleophosmin (NPM) and myelodysplasia/myeloid leukemia factor 1 (MLF1) and myelodysplasia/myeloid leukemia factor 1 (MLF1) is formed by a recurrent t(3;5)(q25.1;q34) in myelodysplastic syndrome and acute myeloid leukemia. Here we report the identification of a novel gene, MLF2, which contains an open reading frame of 744 bp encoding a 248-amino-acid protein highly related to the previously identified MLF1 protein (63% similarity, 40% identity). In contrast to the tissue-restricted expression pattern of MLF1, and MLF2 messenger RNA is expressed ubiquitously. The MLF2 gene locus was mapped by fluorescence in situ hybridization to human chromosome 12p13, a chromosomal region frequently involved in translocations and deletions in acute leukemias of lymphoid or myeloid lineage. In a physical map of chromosome 12, MLF2 was found to reside on the yeast artificial chromosome clone 765b9. Southern blotting analysis of malignant cell DNAs prepared from a series of acute lymphoblastic leukemia cases with translocations involving chromosome arm 12p, as well as a group of acute myeloid leukemias with various cytogenetic abnormalities, failed to reveal MLF2 gene rearrangements. 19 refs., 2 figs.

  17. Chromosomal assignment of chicken clone contigs by extending the consensus linkage map

    NARCIS (Netherlands)

    Aerts, J.; Veenendaal, T.; Poel, van der J.J.; Crooijmans, R.P.M.A.; Groenen, M.A.M.

    2005-01-01

    The bacterial artificial clone-based physical map for chicken plays an important role in the integration of the consensus linkage map and the whole-genome shotgun sequence. It also provides a valuable resource for clone selection within applications such as fluorescent in situ hybridization and posi

  18. Construction and Identification of Bacterial Artificial Chromosome Library for 0-613-2R in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A bacterial artificial chromosome (BAC) library containing a large genomic DNA insert is an important tool for genome physical mapping, map-based cloning, and genome sequencing. To isolate genes via a map-based cloning strategy and to perform physical mapping of the cotton genome, a high-quality BAC library containing large cotton DNA inserts is needed. We have developed a BAC library of the restoring line 0-613-2R for isolating the fertility restorer (Rf1) gene and genomic research in cotton (Gossypium hirsutum L.). The BAC library contains 97 825 clones stored in 255 pieces of a 384-well microtiter plate. Random samples of BACs digested with the Notl enzyme indicated that the average insert size is approximately 130 kb, with a range of 80-275 kb,and 95.7% of the BAC clones in the library have an average insert size larger than 100 kb. Based on a cotton genome size of 2 250 Mb, library coverage is 5.7 x haploid genome equivalents. Four clones were selected randomly from the library to determine the stability of the BAC clones. There were no different fingerprints for 0 and 100 generations of each clone digested with Notl and Hindlll enzymes. Thus, the stability of a single BAC clone can be sustained at least for 100 generations. Eight simple sequence repeat (SSR) markers flanking the Rf1 gene were chosen to screen the BAC library by pool using PCR method and 25 positive clones were identified with 3.1 positive clones per SSR marker.

  19. Cloning and comparative mapping of a human chromosome 4-specific alpha satellite DNA sequence.

    Science.gov (United States)

    D'Aiuto, L; Antonacci, R; Marzella, R; Archidiacono, N; Rocchi, M

    1993-11-01

    We have isolated and characterized two human alphoid DNA clones: p4n1/4 and pZ4.1. Clone p4n1/4 identifies specifically the centromeric region of chromosome 4; pZ4.1 recognizes a subset of alphoid DNA shared by chromosomes 4 and 9. The specificity was determined using fluorescence in situ hybridization experiments on metaphase spreads and Southern blotting analysis of human-hamster somatic cell hybrids. The genomic organization of both subsets was also investigated. Comparative mapping on chimpanzee and gorilla chromosomes was performed. p4n1/4 hybridizes to chimpanzee chromosomes 11 and 13, homologs of human chromosomes 9 and 2q, respectively. On gorilla metaphase spreads, p4n1/4 hybridizes exclusively to the centromeric region of chromosome 19, partially homologous to human chromosome 17. No hybridization signal was detected on chromosome 3 of both chimpanzee and gorilla, in both species homolog of human chromosome 4. Identical comparative mapping results were obtained using pZ4.1 probe, although the latter recognizes an alphoid subset distinct from the one recognized by p4n1/4. The implications of these results in the evolution of centromeric regions of primate chromosomes are discussed.

  20. Cloning and comparative mapping of a human chromosome 4-specific alpha satellite DNA sequence

    Energy Technology Data Exchange (ETDEWEB)

    D' Aiuto, L.; Marzella, R.; Archidiacono, N.; Rocchi, M. (Universita di Bari (Italy)); Antonacci, R. (Instituto Anatomia Umana Normale, Modena (Italy))

    1993-11-01

    The authors have isolated and characterized two human alphoid DNA clones: p4n1/4 and pZ4.1. Clone p4n1/4 identifies specifically the centromeric region of chromosome 4; pZ4.1 recognizes a subset of alphoid DNA shared by chromosomes 4 and 9. The specificity was determined using fluorescence in situ hybridization experiments on metaphase spreads and Southern blotting analysis of human-hamster somatic cell hybrids. The genomic organization of both subsets was also investigated. Comparative mapping on chimpanzee and gorilla chromosomes was performed. p4n1/4 hybridizes to chimpanzee chromosomes 11 and 13, homologs of human chromosomes 9 and 2q, respectively. On gorilla metaphase spreads, p4n1/4 hybridizes exclusively to the centromeric region of chromosome 19, partially homologous to human chromosome 17. No hybridization signal was detected on chromosome 3 of both chimpanzee and gorilla, in both species homolog of human chromosome 4. Identical comparative mapping results were obtained using pZ4.1 probe, although the latter recognizes an alphoid subset distinct from the one recognized by p4n1/4. The implications of these results in the evolution of centromeric regions of primate chromosomes are discussed. 33 refs., 4 figs.

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

    Directory of Open Access Journals (Sweden)

    Changqing Liu

    2013-01-01

    Full Text Available 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.

  2. A bacterial artificial chromosome library for Biomphalaria glabrata, intermediate snail host of Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Coen M Adema

    2006-10-01

    Full Text Available To provide a novel resource for analysis of the genome of Biomphalaria glabrata, members of the international Biomphalaria glabrata Genome Initiative (biology.unm.edu/biomphalaria-genome.html, working with the Arizona Genomics Institute (AGI and supported by the National Human Genome Research Institute (NHGRI, produced a high quality bacterial artificial chromosome (BAC library. The BB02 strain B. glabrata, a field isolate (Belo Horizonte, Minas Gerais, Brasil that is susceptible to several strains of Schistosoma mansoni, was selfed for two generations to reduce haplotype diversity in the offspring. High molecular weight DNA was isolated from ovotestes of 40 snails, partially digested with HindIII, and ligated into pAGIBAC1 vector. The resulting B. glabrata BAC library (BG_BBa consists of 61824 clones (136.3 kb average insert size and provides 9.05 × coverage of the 931 Mb genome. Probing with single/low copy number genes from B. glabrata and fingerprinting of selected BAC clones indicated that the BAC library sufficiently represents the gene complement. BAC end sequence data (514 reads, 299860 nt indicated that the genome of B. glabrata contains ~ 63% AT, and disclosed several novel genes, transposable elements, and groups of high frequency sequence elements. This BG_BBa BAC library, available from AGI at cost to the research community, gains in relevance because BB02 strain B. glabrata is targeted whole genome sequencing by NHGRI.

  3. Construction and Characterization of an Infectious Murine Gammaherpesivrus-68 Bacterial Artificial Chromosome

    Directory of Open Access Journals (Sweden)

    Ting-Ting Wu

    2011-01-01

    Full Text Available Here we describe the cloning of a sequenced WUMS isolate of murine gammaherpesvirus-68 (MHV-68, γHV-68, also known as MuHV-4 as a bacterial artificial chromosome (BAC. We engineered the insertion of the BAC sequence flanked by loxP sites into the left end of the viral genome before the M1 open reading frame. The infectious viruses were reconstituted following transfection of the MHV-68 BAC DNA into cells. The MHV-68 BAC-derived virus replicated indistinguishably from the wild-type virus in cultured cells. Excision of the BAC insert was efficiently achieved by coexpressing the Cre recombinase. Although the BAC insertion did not significantly affect acute productive infection in the lung, it severely compromised the ability of MHV-68 to establish splenic latency. Removal of the BAC sequence restored the wild-type level of latency. Site-specific mutagenesis was carried out by RecA-mediated recombination to demonstrate that this infectious BAC clone can be used for genetic studies of MHV-68.

  4. Functional human artificial chromosomes are generated and stably maintained in human embryonic stem cells

    Science.gov (United States)

    Mandegar, Mohammad A.; Moralli, Daniela; Khoja, Suhail; Cowley, Sally; Chan, David Y.L.; Yusuf, Mohammed; Mukherjee, Sayandip; Blundell, Michael P.; Volpi, Emanuela V.; Thrasher, Adrian J.; James, William; Monaco, Zoia L.

    2011-01-01

    We present a novel and efficient non-integrating gene expression system in human embryonic stem cells (hESc) utilizing human artificial chromosomes (HAC), which behave as autonomous endogenous host chromosomes and segregate correctly during cell division. HAC are important vectors for investigating the organization and structure of the kinetochore, and gene complementation. HAC have so far been obtained in immortalized or tumour-derived cell lines, but never in stem cells, thus limiting their potential therapeutic application. In this work, we modified the herpes simplex virus type 1 amplicon system for efficient transfer of HAC DNA into two hESc. The deriving stable clones generated green fluorescent protein gene-expressing HAC at high frequency, which were stably maintained without selection for 3 months. Importantly, no integration of the HAC DNA was observed in the hESc lines, compared with the fibrosarcoma-derived control cells, where the exogenous DNA frequently integrated in the host genome. The hESc retained pluripotency, differentiation and teratoma formation capabilities. This is the first report of successfully generating gene expressing de novo HAC in hESc, and is a significant step towards the genetic manipulation of stem cells and potential therapeutic applications. PMID:21593218

  5. Efficient assembly of de novo human artificial chromosomes from large genomic loci

    Directory of Open Access Journals (Sweden)

    Stromberg Gregory

    2005-07-01

    Full Text Available Abstract Background Human Artificial Chromosomes (HACs are potentially useful vectors for gene transfer studies and for functional annotation of the genome because of their suitability for cloning, manipulating and transferring large segments of the genome. However, development of HACs for the transfer of large genomic loci into mammalian cells has been limited by difficulties in manipulating high-molecular weight DNA, as well as by the low overall frequencies of de novo HAC formation. Indeed, to date, only a small number of large (>100 kb genomic loci have been reported to be successfully packaged into de novo HACs. Results We have developed novel methodologies to enable efficient assembly of HAC vectors containing any genomic locus of interest. We report here the creation of a novel, bimolecular system based on bacterial artificial chromosomes (BACs for the construction of HACs incorporating any defined genomic region. We have utilized this vector system to rapidly design, construct and validate multiple de novo HACs containing large (100–200 kb genomic loci including therapeutically significant genes for human growth hormone (HGH, polycystic kidney disease (PKD1 and ß-globin. We report significant differences in the ability of different genomic loci to support de novo HAC formation, suggesting possible effects of cis-acting genomic elements. Finally, as a proof of principle, we have observed sustained ß-globin gene expression from HACs incorporating the entire 200 kb ß-globin genomic locus for over 90 days in the absence of selection. Conclusion Taken together, these results are significant for the development of HAC vector technology, as they enable high-throughput assembly and functional validation of HACs containing any large genomic locus. We have evaluated the impact of different genomic loci on the frequency of HAC formation and identified segments of genomic DNA that appear to facilitate de novo HAC formation. These genomic loci

  6. 454 sequencing of pooled BAC clones on chromosome 3H of barley

    Directory of Open Access Journals (Sweden)

    Yamaji Nami

    2011-05-01

    Full Text Available Abstract Background Genome sequencing of barley has been delayed due to its large genome size (ca. 5,000Mbp. Among the fast sequencing systems, 454 liquid phase pyrosequencing provides the longest reads and is the most promising method for BAC clones. Here we report the results of pooled sequencing of BAC clones selected with ESTs genetically mapped to chromosome 3H. Results We sequenced pooled barley BAC clones using a 454 parallel genome sequencer. A PCR screening system based on primer sets derived from genetically mapped ESTs on chromosome 3H was used for clone selection in a BAC library developed from cultivar "Haruna Nijo". The DNA samples of 10 or 20 BAC clones were pooled and used for shotgun library development. The homology between contig sequences generated in each pooled library and mapped EST sequences was studied. The number of contigs assigned on chromosome 3H was 372. Their lengths ranged from 1,230 bp to 58,322 bp with an average 14,891 bp. Of these contigs, 240 showed homology and colinearity with the genome sequence of rice chromosome 1. A contig annotation browser supplemented with query search by unique sequence or genetic map position was developed. The identified contigs can be annotated with barley cDNAs and reference sequences on the browser. Homology analysis of these contigs with rice genes indicated that 1,239 rice genes can be assigned to barley contigs by the simple comparison of sequence lengths in both species. Of these genes, 492 are assigned to rice chromosome 1. Conclusions We demonstrate the efficiency of sequencing gene rich regions from barley chromosome 3H, with special reference to syntenic relationships with rice chromosome 1.

  7. Repetitive genome elements in a European corn borer, Ostrinia nubilalis, bacterial artificial chromosome library were indicated by bacterial artificial chromosome end sequencing and development of sequence tag site markers: implications for lepidopteran genomic research.

    Science.gov (United States)

    Coates, Brad S; Sumerford, Douglas V; Hellmich, Richard L; Lewis, Leslie C

    2009-01-01

    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 library constructed for O. nubilalis contains 36 864 clones with an estimated average insert size of >or=120 kb and genome coverage of 8.8-fold. Screening OnB1 clones comprising approximately 2.76 genome equivalents determined the physical position of 24 sequence tag site markers, including markers linked to ecologically important and Bacillus thuringiensis toxin resistance traits. OnB1 bacterial artificial chromosome end sequence reads (GenBank dbGSS accessions ET217010 to ET217273) showed homology to annotated genes or expressed sequence tags and identified repetitive genome elements, O. nubilalis miniature subterminal inverted repeat transposable elements (OnMITE01 and OnMITE02), and ezi-like long interspersed nuclear elements. Mobility of OnMITE01 was demonstrated by the presence or absence in O. nubilalis of introns at two different loci. A (GTCT)n tetranucleotide repeat at the 5' ends of OnMITE01 and OnMITE02 are evidence for transposon-mediated movement of lepidopteran microsatellite loci. The number of repetitive elements in lepidopteran genomes will affect genome assembly and marker development. Single-locus sequence tag site markers described here have downstream application for integration within linkage maps and comparative genomic studies.

  8. Construction of an Americn mink Bacterial Artificial Chromosome (BAC) library and sequencing candidate genes important for the fur industry

    DEFF Research Database (Denmark)

    Anistoroaei, Razvan Marian; Hallers, Boudewijn ten; Nefedov, Michael

    2011-01-01

    consisting of 18,432 clones spotted in duplicate, have been produced for hybridization screening and are publicly available. Overgo probes derived from expressed sequence tags (ESTs), representing 21 candidate genes for traits important for the mink industry, were used to screen the BAC library......BACKGROUND: Bacterial artificial chromosome (BAC) libraries continue to be invaluable tools for the genomic analysis of complex organisms. Complemented by the newly and fast growing deep sequencing technologies, they provide an excellent source of information in genomics projects. RESULTS: Here, we...... report the construction and characterization of the CHORI-231 BAC library constructed from a Danish-farmed, male American mink (Neovison vison). The library contains approximately 165,888 clones with an average insert size of 170 kb, representing approximately 10-fold coverage. High-density filters, each...

  9. Construction and characterization of a 10-genome equivalent yeast artificial chromosome library for the laboratory rat, Rattus norvegicus

    Energy Technology Data Exchange (ETDEWEB)

    Cai, L.; Zee, R.Y.L. [Harvard Medical School, Boston, MA (United States); Schalkwyk, L.C. [Max Planck Institute for Molecular Genetics, Berlin (Germany)] [and others

    1997-02-01

    Increasing attention has been focused in recent years on the rat as a model organism for genetic studies, in particular for the investigation of complex traits, but progress has been limited by the lack of availability of large-insert genomic libraries. Here, we report the construction and characterization of an arrayed yeast artificial chromosome (YAC) library for the rat genome containing approximately 40,000 clones in the AB1380 host using the pCGS966 vector. An average size of 736 kb was estimated from 166 randomly chosen clones; thus the library provides 10-fold coverage of the genome, with a 99.99% probability of containing a unique sequence. Eight of 39 YACs analyzed by fluorescence in situ hybridization were found to be chimeric, indicating a proportion of about 20-30% of chimeric clones. The library was spotted on high-density filters to allow the identification of YAC clones by hybridization and was pooled using a 3-dimensional scheme for screening by PCR. Among 48 probes used to screen the library, an average of 9.3 positive clones were found, consistent with the calculated 10-fold genomic coverage of the library. This YAC library represents the first large-insert genomic library for the rat. It will be made available to the research community at large as an important new resource for complex genome analysis in this species. 35 refs., 4 figs.

  10. Construction and characterization of a bacterial artificial chromosome library of thermo-sensitive genic male-sterile rice 5460S

    Institute of Scientific and Technical Information of China (English)

    邱芳; 金德敏; 伏健民; 张超良; 谢纬武; 王斌; 杨仁崔; 张洪斌

    1999-01-01

    In order to develop a detailed physical map of the thermo-sensitive genie male-sterile (TGMS) gene-encompassing region and finally clone the TGMS gene, a high-quality rice bacterial artificial chromosome (BAC) library from TGMS rice 5460S was constructed. The method of constructing BAC library was examined and optimized. The 5460S library consists of 19 584 BAC clones with an average insert size of 110 kb, which represents about 5 times rice haploid genome equivalents. Rice inserts of up to 140 kb and 250 kb were isolated and appeared stable after 100 generations of serial growth. Hybridization of BAC clones with mitochondrial and chloroplastic genes as probes demonstrated that this library has no organellar contamination. The 5460S library was screened with 3 molecular markers linked to tmsl gene as probes and at least 1 BAC clone was identified with each probe. The insert ends of positive clones were successfully isolated using thermal asymmetric interlaced PCR (TAIL-PCR) technique.

  11. Using Bacterial Artificial Chromosomes in Leukemia Research: The Experience at the University Cytogenetics Laboratory in Brest, France

    Directory of Open Access Journals (Sweden)

    Etienne De Braekeleer

    2011-01-01

    Full Text Available The development of the bacterial artificial chromosome (BAC system was driven in part by the human genome project in order to construct genomic DNA libraries and physical maps for genomic sequencing. The availability of BAC clones has become a valuable tool for identifying cancer genes. We report here our experience in identifying genes located at breakpoints of chromosomal rearrangements and in defining the size and boundaries of deletions in hematological diseases. The methodology used in our laboratory consists of a three-step approach using conventional cytogenetics followed by FISH with commercial probes, then BAC clones. One limitation to the BAC system is that it can only accommodate inserts of up to 300 kb. As a consequence, analyzing the extent of deletions requires a large amount of material. Array comparative genomic hybridization (array-CGH using a BAC/PAC system can be an alternative. However, this technique has limitations also, and it cannot be used to identify candidate genes at breakpoints of chromosomal rearrangements such as translocations, insertions, and inversions.

  12. Using bacterial artificial chromosomes in leukemia research: the experience at the university cytogenetics laboratory in Brest, France.

    Science.gov (United States)

    De Braekeleer, Etienne; Douet-Guilbert, Nathalie; Basinko, Audrey; Morel, Frédéric; Le Bris, Marie-Josée; Férec, Claude; De Braekeleer, Marc

    2011-01-01

    The development of the bacterial artificial chromosome (BAC) system was driven in part by the human genome project in order to construct genomic DNA libraries and physical maps for genomic sequencing. The availability of BAC clones has become a valuable tool for identifying cancer genes. We report here our experience in identifying genes located at breakpoints of chromosomal rearrangements and in defining the size and boundaries of deletions in hematological diseases. The methodology used in our laboratory consists of a three-step approach using conventional cytogenetics followed by FISH with commercial probes, then BAC clones. One limitation to the BAC system is that it can only accommodate inserts of up to 300 kb. As a consequence, analyzing the extent of deletions requires a large amount of material. Array comparative genomic hybridization (array-CGH) using a BAC/PAC system can be an alternative. However, this technique has limitations also, and it cannot be used to identify candidate genes at breakpoints of chromosomal rearrangements such as translocations, insertions, and inversions.

  13. Molecular cloning, chromosomal mapping, and functional expression of human brain glutamate receptors

    Energy Technology Data Exchange (ETDEWEB)

    Sun, W.; Ferrer-Montiel, A.V.; Schinder, A.F.; Montal, M. (Univ. of California, San Diego, La Jolla (United States)); McPherson, J.P. (Univ. of California, Irvine (United States)); Evans, G.A. (Salk Inst. for Biological Studies, La Jolla, CA (United States))

    1992-02-15

    A full-length cDNA clone encoding a glutamate receptor was isolated from a human brain cDNA library, and the gene product was characterized after expression in Xenopus oocytes. Degenerate PCR primers to conserved regions of published rat brain glutamate receptor sequences amplified a 1-kilobase fragment from a human brain cDNA library. This fragment was used as a probe for subsequent hybridization screening. Two clones were isolated that, based on sequence information, code for different receptors: a 3-kilobase clone, HBGR1, contains a full-length glutamate receptor cDNA highly homologous to the rat brain clone GluR1, and a second clone, HBGR2, contains approximately two-thirds of the coding region of a receptor homologous to rat brain clone GluR2. Southern and PCr analysis of a somatic cell-hybrid panel mapped HBGR1 to human chromosome 5q31.3-33.3 and mapped HBGR2 to chromosome 4q25-34.3. Xenopus oocytes injected with in vitro-synthesized HBGR1 cRNA expressed currents activated by glutamate receptor agonists. These results indicate that clone HBGR1 codes for a glutamate receptor of the kainate subtype cognate to members of the glutamate receptor family from rodent brain.

  14. Construction and Analysis of Siberian Tiger Bacterial Artificial Chromosome Library with Approximately 6.5-Fold Genome Equivalent Coverage

    Directory of Open Access Journals (Sweden)

    Changqing Liu

    2014-03-01

    Full Text Available Bacterial artificial chromosome (BAC libraries are extremely valuable for the genome-wide genetic dissection of complex organisms. The Siberian tiger, one of the most well-known wild primitive carnivores in China, is an endangered animal. In order to promote research on its genome, a high-redundancy BAC library of the Siberian tiger was constructed and characterized. The library is divided into two sub-libraries prepared from blood cells and two sub-libraries prepared from fibroblasts. This BAC library contains 153,600 individually archived clones; for PCR-based screening of the library, BACs were placed into 40 superpools of 10 × 384-deep well microplates. The average insert size of BAC clones was estimated to be 116.5 kb, representing approximately 6.46 genome equivalents of the haploid genome and affording a 98.86% statistical probability of obtaining at least one clone containing a unique DNA sequence. Screening the library with 19 microsatellite markers and a SRY sequence revealed that each of these markers were present in the library; the average number of positive clones per marker was 6.74 (range 2 to 12, consistent with 6.46 coverage of the tiger genome. Additionally, we identified 72 microsatellite markers that could potentially be used as genetic markers. This BAC library will serve as a valuable resource for physical mapping, comparative genomic study and large-scale genome sequencing in the tiger.

  15. Construction and analysis of Siberian tiger bacterial artificial chromosome library with approximately 6.5-fold genome equivalent coverage.

    Science.gov (United States)

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

    2014-03-07

    Bacterial artificial chromosome (BAC) libraries are extremely valuable for the genome-wide genetic dissection of complex organisms. The Siberian tiger, one of the most well-known wild primitive carnivores in China, is an endangered animal. In order to promote research on its genome, a high-redundancy BAC library of the Siberian tiger was constructed and characterized. The library is divided into two sub-libraries prepared from blood cells and two sub-libraries prepared from fibroblasts. This BAC library contains 153,600 individually archived clones; for PCR-based screening of the library, BACs were placed into 40 superpools of 10 × 384-deep well microplates. The average insert size of BAC clones was estimated to be 116.5 kb, representing approximately 6.46 genome equivalents of the haploid genome and affording a 98.86% statistical probability of obtaining at least one clone containing a unique DNA sequence. Screening the library with 19 microsatellite markers and a SRY sequence revealed that each of these markers were present in the library; the average number of positive clones per marker was 6.74 (range 2 to 12), consistent with 6.46 coverage of the tiger genome. Additionally, we identified 72 microsatellite markers that could potentially be used as genetic markers. This BAC library will serve as a valuable resource for physical mapping, comparative genomic study and large-scale genome sequencing in the tiger.

  16. Transfer of stem cells carrying engineered chromosomes with XY clone laser system.

    Science.gov (United States)

    Sinko, Ildiko; Katona, Robert L

    2011-01-01

    Current transgenic technologies for gene transfer into the germline of mammals cause a random integration of exogenous naked DNA into the host genome that can generate undesirable position effects as well as insertional mutations. The vectors used to generate transgenic animals are limited by the amount of foreign DNA they can carry. Mammalian artificial chromosomes have large DNA-carrying capacity and ability to replicate in parallel with, but without integration into, the host genome. Hence they are attractive vectors for transgenesis, cellular protein production, and gene therapy applications as well. ES cells mediated chromosome transfer by conventional blastocyst injection has a limitation in unpredictable germline transmission. The demonstrated protocol of laser-assisted microinjection of artificial chromosome containing ES cells into eight-cell mouse embryos protocol described here can solve the problem for faster production of germline transchromosomic mice.

  17. Development and Application of a Transformation-competent Artificial chromosome (TAC) Genomic DNA Library in Allotetrapolid Cotton (Gossypium hirsutum L. )%陆地棉TAC基因组DNA文库的构建及利用

    Institute of Scientific and Technical Information of China (English)

    Xiao-e LIANG; Jin-feng SUO; Yong-biao XUE

    2002-01-01

    @@ The technology of cloning and transferring of large DNA fragments in plants is important for high-efficient identification of new genes and study of gene functions. Tranformationcompetent artificial chromosome (TAC) vector system has been shown to be very useful for efficient gene isolation in Arobidopsis thaliana.

  18. Helper plasmid cloning in Streptococcus sanguis: cloning of a tetracycline resistance determinant from the Streptococcus mutans chromosome.

    Science.gov (United States)

    Tobian, J A; Macrina, F L

    1982-10-01

    A model system for testing the helper plasmid cloning system of Gryczan et al. (Mol. Gen. Genet. 177:459-467, 1980) was devised for the Streptococcus sanguis (Challis) host-vector system. In this system, linearized pVA736 plasmid efficiently transformed an S. sanguis (Challis) host containing a homologous plasmid, pVA380-1, but did not transform a plasmidless host or a host containing a nonhomologous plasmid, pVA380. In addition, whereas monomeric circular pVA736 transformed a plasmidless host with two-hit kinetics, it transformed a pVA380-1-containing host with one-hit kinetics. This helper plasmid cloning system was used to isolate two HindIII fragments (5.0 megadaltons [Mdal] and 1.9 Mdal in size) from the chromosome of Streptococcus mutans V825 which conferred high-level tetracycline resistance. One tetracycline-resistant clone was examined and found to contain three plasmids which were sized and designated pVA868 (9.0 Mdal), pVA869 (9.5 Mdal), and pVA870 (9.8 Mdal). Results of Southern blot hybridization and restriction endonuclease digestion confirmed that all three chimeras were composed of two HindIII fragments of the S. mutans V825 chromosome, as well as a large portion, varying in size for each chimera, of the 2.8 Mdal cloning vector, pVA380-1. Incompatibility observed between pVA380-1 and each of the chimeras indicated that replication of the chimeras was governed by the pVA380-1 replicative origin. Southern blotting experiments revealed that the chimeras hybridized to Tn916, providing the first evidence that transposon-related genes of enteric streptococcal origin are disseminated among oral streptococci.

  19. Island rescue PCR: a rapid and efficient method for isolating transcribed sequences from yeast artificial chromosomes and cosmids.

    Science.gov (United States)

    Valdes, J M; Tagle, D A; Collins, F S

    1994-06-07

    The identification of transcripts from large genomic regions cloned in yeast artificial chromosomes (YACs) or cosmids continues to be a critical and often rate-limiting step in positional cloning of human disease genes. We have developed a PCR-based method for rapid and efficient generation of probes from YACs or cosmids that can be used for cDNA library screening. The method, which we call island rescue PCR (IRP), is based upon the observation that the 5' ends of many genes are associated with (G+C)-rich regions called CpG islands. In IRP, the YAC of interest is digested with a restriction enzyme that recognizes sequences of high CpG content, and vectorette linkers are ligated to the cleaved ends. The PCR is used to amplify the region extending from the cleaved restriction enzyme site to the nearest SINE (Alu) repeat. In many cases this product contains sequences from the 5' end of the associated gene. cDNA clones isolated with these products are then verified by mapping them back to the original YAC. The method allows rapid screening of > 500 kb of human genomic insert in one experiment, is tolerant of contaminating yeast sequences, and can also be applied to cosmid pools. In a control experiment, the method was able to identify cDNA clones for the neurofibromatosis type 1 (NF1) gene using a probe generated from a YAC in the region. Application of IRP has yielded nine other genes from YACs isolated from chromosome locations 4p16.3 and 17q21.

  20. Comparative mapping of a gorilla-derived alpha satellite DNA clone on great ape and human chromosomes.

    Science.gov (United States)

    Baldini, A; Miller, D A; Shridhar, V; Rocchi, M; Miller, O J; Ward, D C

    1991-11-01

    We have isolated an alpha satellite DNA clone, pG3.9, from gorilla DNA. Fluorescence in situ hybridization on banded chromosomes under high stringency conditions revealed that pG3.9 identifies homologous sequences at the centromeric region of ten gorilla chromosomes, and, with few exceptions, also recognizes the homologous chromosomes in human. A pG3.9-like alphoid DNA is present on a larger number of orangutan chromosomes, but, in contrast, is present on only two chromosomes in the chimpanzee. These results show that the chromosomal subsets of related alpha satellite DNA sequences may undergo different patterns of evolution.

  1. Human nicotinamide N-methyltransferase gene: Molecular cloning, structural characterization and chromosomal localization

    Energy Technology Data Exchange (ETDEWEB)

    Aksoy, S.; Weinshilboum, R.M. [Mayo Medical School/Mayo Clinic/Mayo Foundation, Rochester, MN (United States); Brandriff, B.F. [Lawrence Livermore National Lab., CA (United States); Ward, A.; Little, P.F.R. [Imperial College of Science, Technology and Medicine, London (United Kingdom)

    1995-10-10

    Genomic DNA clones for nicotinamide N-methyltransferase (NNMT), an enzyme that catalyzes drug and xenobiotic metabolism, were isolated from a human chromosome 11-specific DNA library. Study of one of those clones, when combined with PCR-based experiments performed with human genomic DNA, made it possible to determine the structure of the human NNMT gene. The gene was approximately 16.5 kb in length and consisted of 3 exons and 2 introns. Transcription initiation for the NNMT gene occurred 105-109 nucleotides 5{prime}-upstream from the cDNA translation initiation codon on the basis of the results of both primer extension and 5{prime}-rapid amplification of cDNA ends. NNMT mapped to chromosome band 11q23.1 by fluorescence in situ hybridization.

  2. From amplification to gene in thyroid cancer: A high-resolution mapped bacterial-artificial-chromosome resource for cancer chromosome aberrations guides gene discovery after comparative genome hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Chen, X.N.; Gonsky, R.; Korenberg, J.R. [UCLA School of Medicine, Los Angeles, CA (United States). Cedars-Sinai Research Inst.; Knauf, J.A.; Fagin, J.A. [Univ. of Cincinnati, OH (United States). Div. of Endocrinology/Metabolism; Wang, M.; Lai, E.H. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Pharmacology; Chissoe, S. [Washington Univ. School of Medicine, St. Louis, MO (United States). Genome Sequencing

    1998-08-01

    Chromosome rearrangements associated with neoplasms provide a rich resource for definition of the pathways of tumorigenesis. The power of comparative genome hybridization (CGH) to identify novel genes depends on the existence of suitable markers, which are lacking throughout most of the genome. The authors now report a general approach that translates CGH data into higher-resolution genomic-clone data that are then used to define the genes located in aneuploid regions. They used CGH to study 33 thyroid-tumor DNAs and two tumor-cell-line DNAs. The results revealed amplifications of chromosome band 2p21, with less-intense amplification on 2p13, 19q13.1, and 1p36 and with least-intense amplification on 1p34, 1q42, 5q31, 5q33-34, 9q32-34, and 14q32. To define the 2p21 region amplified, a dense array of 373 FISH-mapped chromosome 2 bacterial artificial chromosomes (BACs) was constructed, and 87 of these were hybridized to a tumor-cell line. Four BACs carried genomic DNA that was amplified in these cells. The maximum amplified region was narrowed to 3--6 Mb by multicolor FISH with the flanking BACs, and the minimum amplicon size was defined by a contig of 420 kb. Sequence analysis of the amplified BAC 1D9 revealed a fragment of the gene, encoding protein kinase C epsilon (PKC{epsilon}), that was then shown to be amplified and rearranged in tumor cells. In summary, CGH combined with a dense mapped resource of BACs and large-scale sequencing has led directly to the definition of PKC{epsilon} as a previously unmapped candidate gene involved in thyroid tumorigenesis.

  3. 45,X/46,XY chromosome mosaicism detected by midtrimester amniocentesis in amniocyte clones.

    Science.gov (United States)

    Hecht, F; Hecht, B K

    1982-07-01

    Amniocyte clones from a mild-trimester pregnancy disclosed 45,X/46,XY sex chromosome mosaicism. Because of the uncertainty concerning the phenotype of the fetus, the parents elected to terminate the pregnancy. Mixed (asymmetrical) gonadal dysgenesis was not found. The fetus appeared to have a normal male uro-genital system. No malformations of any type were detected, although as expected, the fetus did have 45,X/46,XY mosaicism.

  4. Construction and Characterization of a Bacterial Artificial Chromosome Library for the A-Genome of Cotton (G. arboreum L.

    Directory of Open Access Journals (Sweden)

    Yan Hu

    2011-01-01

    Full Text Available A bacterial artificial chromosome (BAC library for the A-genome of cotton has been constructed from the leaves of G. arboreum L cv. Jianglinzhongmian. It is used as elite A-genome germplasm resources in the present cotton breeding program and has been used to build a genetic reference map of cotton. The BAC library consists of 123,648 clones stored in 322 384-well plates. Statistical analysis of a set of 103 randomly selected BAC clones indicated that each clone has an average insert length of 100.2 kb per plasmid, with a range of 30 to 190 kb. Theoretically, this represents 7.2 haploid genome equivalents based on an A-genome size of 1697 Mb. The BAC library has been arranged in column pools and superpools allowing screening with various PCR-based markers. In the future, the A-genome cotton BAC library will serve as both a giant gene resource and a valuable tool for map-based gene isolation, physical mapping and comparative genome analysis.

  5. Highly efficient modification of bacterial artificial chromosomes (BACs) using novel shuttle vectors containing the R6Kgamma origin of replication.

    Science.gov (United States)

    Gong, Shiaoching; Yang, Xiangdong William; Li, Chenjian; Heintz, Nathaniel

    2002-12-01

    Bacterial artificial chromosome (BAC) mediated transgenesis has proven to be a highly reliable way to obtain accurate transgene expression for in vivo studies of gene expression and function. A rate-limiting step in use of this technology to characterize large numbers of genes has been the process with which BACs can be modified by homologous recombination in Escherichia coli. We report here a highly efficient method for modifying BACs by using a novel set of shuttle vectors that contain the R6Kgamma origin for DNA replication, the E. coli RecA gene for recombination, and the SacB gene for negative selection. These new vectors greatly increased the ease with which one can clone the shuttle vectors, as well as screen for co-integrated and resolved clones. Furthermore, we simplify the shuttle vector cloning to one step by incorporation of a "built-in" resolution cassette for rapid removal of the unwanted vector sequences. This new system has been used to modify a dozen BACs. It is well suited for efficient production of modified BACs for use in a variety of in vivo studies.

  6. Identification and cloning of the CHL4 gene controlling chromosome segregation in yeast.

    Science.gov (United States)

    Kouprina, N; Kirillov, A; Kroll, E; Koryabin, M; Shestopalov, B; Bannikov, V; Zakharyev, V; Larionov, V

    1993-10-01

    A collection of chl mutants characterized by decreased fidelity of chromosome transmission and by minichromosome nondisjunction in mitosis was examined for the ability to maintain nonessential dicentric plasmids. In one of the seven mutants analyzed, chl4, dicentric plasmids did not depress cell division. Moreover, nonessential dicentric plasmids were maintained stably without any rearrangements during many generations in the chl4 mutant. The rate of mitotic heteroallelic recombination in the chl4 mutant was not increased compared to that in an isogenic wild-type strain. Analysis of the segregation of a marked chromosome indicated that sister chromatid nondisjunction and sister chromatid loss contributed equally to chromosome malsegregation in the chl4 mutant. A genomic clone of CHL4 was isolated by complementation of the chl4-1 mutation and was physically mapped to the right arm of chromosome IV near the SUP2 gene. Nucleotide sequence analysis of CHL4 clone revealed a 1.4-kb open reading frame coding for a 53-kD predicted protein which does not have homology to published proteins. A strain containing a null allele of CHL4 is viable under standard growth conditions but has a temperature-sensitive phenotype (conditional lethality at 36 degrees). We suggest that the CHL4 gene is required for kinetochore function in the yeast Saccharomyces cerevisiae.

  7. Cloning of DNA sequences localized on proximal fluorescent chromosome bands by microdissection in Pinus densiflora Sieb. & Zucc.

    Science.gov (United States)

    Hizume, M; Shibata, F; Maruyama, Y; Kondo, T

    2001-09-01

    Japanese red pine, Pinus densiflora, has 2n=24 chromosomes, of which most carry chromomycin A3 (CMA) and 4',6-diamidino-2-phenylindole (DAPI) bands at their centromere-proximal regions. It was proposed that these regions contain highly repetitive DNA. The DNA localized in the proximal fluorescent bands was isolated and characterized. In P. densiflora, centromeric and neighboring segments of the somatic chromosomes were dissected with a manual micromanipulator. The centromeric DNA was amplified from the DNA contained in dissected centromeric segments by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) and a cloned DNA library was constructed. Thirty-one clones carrying highly repetitive DNA were selected by colony hybridization using Cot-1 DNA from this species as a probe, and their chromosomal localization was determined by fluorescent in situ hybridization (FISH). Clone PDCD501 was localized to the proximal CMA band of 20 chromosomes. This clone contained tandem repeats, comprising a 27 bp repeat unit, which was sufficient to provide the proximal FISH signal, with a 52.3% GC content. The repetitive sequence was named PCSR (proximal CMA band-specific repeat). Clone PDCD159 was 1700 bp in length, with a 61.7% AT content, and produced FISH signals at the proximal DAPI band of the remaining four chromosomes. Four clones hybridized strongly to the secondary constriction and gave weak signals at the centromeric region of several chromosomes. Clone PDCD537, one of the four clones, was homologous to the 26S rRNA gene. A PCR experiment using microdissected centromeric regions suggested that the centromeric region contains 18S and 26S rDNA. Another 24 clones hybridized to whole chromosome arms, with varying intensities and might represent dispersed repetitive DNA.

  8. Quality control of the sheep bacterial artificial chromosome library, CHORI-243

    Directory of Open Access Journals (Sweden)

    Kirkness Ewen F

    2010-12-01

    Full Text Available Abstract Background The sheep CHORI-243 bacterial artificial chromosome (BAC library is being used in the construction of the virtual sheep genome, the sequencing and construction of the actual sheep genome assembly and as a source of DNA for regions of the genome of biological interest. The objective of our study is to assess the integrity of the clones and plates which make up the CHORI-243 library using the virtual sheep genome. Findings A series of analyses were undertaken based on the mapping the sheep BAC-end sequences (BESs to the virtual sheep genome. Overall, very few plate specific biases were identified, with only three of the 528 plates in the library significantly affected. The analysis of the number of tail-to-tail (concordant BACs on the plates identified a number of plates with lower than average numbers of such BACs. For plates 198 and 213 a partial swap of the BESs determined with one of the two primers appear to have occurred. A third plate, 341, also with a significant deficit in tail-to-tail BACs, appeared to contain a substantial number of sequences determined from contaminating eubacterial 16 S rRNA DNA. Additionally a small number of eubacterial 16 S rRNA DNA sequences were present on two other plates, 111 and 338, in the library. Conclusions The comparative genomic approach can be used to assess BAC library integrity in the absence of fingerprinting. The sequences of the sheep CHORI-243 library BACs have high integrity, especially with the corrections detailed above. The library represents a high quality resource for use by the sheep genomics community.

  9. A Study for the Feature Selection to Identify GIEMSA-Stained Human Chromosomes Based on Artificial Neural Network

    Science.gov (United States)

    2007-11-02

    neural network (ANN) has been adopted for the human chromosome classification. It is important to select optimum features for training neural network...Many studies for computer-based chromosome analysis have shown that it is possible to classify chromosomes into 24 subgroups. In addition, artificial

  10. Fungal artificial chromosomes for mining of the fungal secondary metabolome

    OpenAIRE

    2015-01-01

    Background With thousands of fungal genomes being sequenced, each genome containing up to 70 secondary metabolite (SM) clusters 30–80 kb in size, breakthrough techniques are needed to characterize this SM wealth. Results Here we describe a novel system-level methodology for unbiased cloning of intact large SM clusters from a single fungal genome for one-step transformation and expression in a model host. All 56 intact SM clusters from Aspergillus terreus were individually captured in self-rep...

  11. Advances and perspectives in artificial chromosomes%人工染色体研究进展

    Institute of Scientific and Technical Information of China (English)

    李林川; 韩方普

    2011-01-01

    Artificial chromosomes (ACs) are genetic-engineered vector systems with defined native chromosomal elements.ACs have large carrying capacity and genetic stability without integration into host genome, thus avoiding random insertion and positional effects.ACs were first successfully developed in yeast (Yeast artificial chromosome, YAC), and then in bacterium (Bacterial artificial chromosome, BAC), human (Human artificial chromosome, HAC), and plant (Plant artificial chromosome, PAC).Here, we summarized recent progress on ACs, especially, on PAC.To date, YAC and BAC have been widely applied in genome sequencing and gene isolation, while HAC and PAC have been subjected to gene therapy, protein production, and plant transgenesis, respectively.Recently, American scientists reported a man-made genome of prokaryote Mycoplasma mycoides.However, like ACs, this man-made genome was also genetic-engineered product and can't survive as an independent life without a cellular environment.%人工染色体是人工构建的含有天然染色体基本功能单位的载体系统总称.人工染色体是非常优良的载体,具有超大的接受外源片段能力.由于不用整合到宿主基因组中,因此不会引起宿主基因的插入失活,及抑制转基因表达的位置效应.人工染色体已经从最初的酵母人工染色体((Yeast artificial chromosome,YAC)发展到细菌人工染色体(Bacterial artificial chromosome,BAC),再扩展到人类人工染色体(Human artificial chromosome,HAC)和植物人工染色体(Plant artificial chromosome,PAC).文章就这4种人工染色体,尤其是植物人工染色体的研究进展和应用局限进行综述.目前,YAC和BAC已经广泛应用于基因组图谱制作、序列测定和基因克隆;HAC和PAC在基因治疗、外源医用蛋白的生产、新型优质高产高抗转墓因作物构建中显现出广阔的应用前景.随着合成生物学的高速发展,美国科学家报道合成了一个"人造生命".但是,

  12. Construction of an American mink Bacterial Artificial Chromosome (BAC library and sequencing candidate genes important for the fur industry

    Directory of Open Access Journals (Sweden)

    Christensen Knud

    2011-07-01

    Full Text Available Abstract Background Bacterial artificial chromosome (BAC libraries continue to be invaluable tools for the genomic analysis of complex organisms. Complemented by the newly and fast growing deep sequencing technologies, they provide an excellent source of information in genomics projects. Results Here, we report the construction and characterization of the CHORI-231 BAC library constructed from a Danish-farmed, male American mink (Neovison vison. The library contains approximately 165,888 clones with an average insert size of 170 kb, representing approximately 10-fold coverage. High-density filters, each consisting of 18,432 clones spotted in duplicate, have been produced for hybridization screening and are publicly available. Overgo probes derived from expressed sequence tags (ESTs, representing 21 candidate genes for traits important for the mink industry, were used to screen the BAC library. These included candidate genes for coat coloring, hair growth and length, coarseness, and some receptors potentially involved in viral diseases in mink. The extensive screening yielded positive results for 19 of these genes. Thirty-five clones corresponding to 19 genes were sequenced using 454 Roche, and large contigs (184 kb in average were assembled. Knowing the complete sequences of these candidate genes will enable confirmation of the association with a phenotype and the finding of causative mutations for the targeted phenotypes. Additionally, 1577 BAC clones were end sequenced; 2505 BAC end sequences (80% of BACs were obtained. An excess of 2 Mb has been analyzed, thus giving a snapshot of the mink genome. Conclusions The availability of the CHORI-321 American mink BAC library will aid in identification of genes and genomic regions of interest. We have demonstrated how the library can be used to identify specific genes of interest, develop genetic markers, and for BAC end sequencing and deep sequencing of selected clones. To our knowledge, this is the

  13. Cloning, chromosome localization and features of a novel human gene, MATH2

    Indian Academy of Sciences (India)

    Lingchen Guo; Min Jiang; Yushu Ma; Haipeng Cheng; Xiaohua Ni; Yangsheng Jin; Yi Xie; Yumin Mao

    2002-04-01

    We report cloning and some features of a novel human gene, MATH2, which encodes a protein of 337 amino acid residues with a basic helix–loop–helix domain and exhibits 98% similarity to mouse Math2. Results of Northern blot analysis revealed two transcripts of the MATH2 gene of 1.7 kb and 2.4 kb in human brain. We localized MATH2 to chromosome 7 at 7p14–15 by matching with the Human Genome Sequence Database. Human MATH2 and mouse Math2 may have the same functions in the nervous system.

  14. Developing de novo human artificial chromosomes in embryonic stem cells using HSV-1 amplicon technology.

    Science.gov (United States)

    Moralli, Daniela; Monaco, Zoia L

    2015-02-01

    De novo artificial chromosomes expressing genes have been generated in human embryonic stem cells (hESc) and are maintained following differentiation into other cell types. Human artificial chromosomes (HAC) are small, functional, extrachromosomal elements, which behave as normal chromosomes in human cells. De novo HAC are generated following delivery of alpha satellite DNA into target cells. HAC are characterized by high levels of mitotic stability and are used as models to study centromere formation and chromosome organisation. They are successful and effective as gene expression vectors since they remain autonomous and can accommodate larger genes and regulatory regions for long-term expression studies in cells unlike other viral gene delivery vectors currently used. Transferring the essential DNA sequences for HAC formation intact across the cell membrane has been challenging for a number of years. A highly efficient delivery system based on HSV-1 amplicons has been used to target DNA directly to the ES cell nucleus and HAC stably generated in human embryonic stem cells (hESc) at high frequency. HAC were detected using an improved protocol for hESc chromosome harvesting, which consistently produced high-quality metaphase spreads that could routinely detect HAC in hESc. In tumour cells, the input DNA often integrated in the host chromosomes, but in the host ES genome, it remained intact. The hESc containing the HAC formed embryoid bodies, generated teratoma in mice, and differentiated into neuronal cells where the HAC were maintained. The HAC structure and chromatin composition was similar to the endogenous hESc chromosomes. This review will discuss the technological advances in HAC vector delivery using HSV-1 amplicons and the improvements in the identification of de novo HAC in hESc.

  15. Fluorescence in situ hybridization with Bacterial Artificial Chromosomes (BACs) to mitotic heterochromatin of Drosophila.

    Science.gov (United States)

    Accardo, Maria Carmela; Dimitri, Patrizio

    2010-01-01

    The organization of eukaryotic chromosomes into euchromatin and heterochromatin represents an enigmatic aspect of genome evolution. Constitutive heterochromatin is a basic, yet still poorly understood component of eukaryotic genomes and its molecular characterization by means of standard genomic approaches is intrinsically difficult. Drosophila melanogaster polytene chromosomes do not seem to be particularly useful to map heterochromatin sequences because the typical features of heterochromatin, organized as it is into a chromocenter, limit cytogenetic analysis. In contrast, constitutive heterochromatin has been well-defined at the cytological level in mitotic chromosomes of neuroblasts and has been subdivided into several bands with differential staining properties. Fluorescence in situ hybridization (FISH) using Bacterial Artificial Chromosomes (BAC) probes that carry large genomic portions defined by sequence annotation has yielded a "revolution" in the field of cytogenetics because it has allowed the mapping of multiple genes at once, thus rendering constitutive heterochromatin amenable to easy and fast cytogenetics analyses. Indeed, BAC-based FISH approaches on Drosophila mitotic chromosomes have made it possible to correlate genomic sequences to their cytogenetic location, aiming to build an integrated map of the pericentric heterochromatin. This chapter presents our standard protocols for BAC-based FISH, aimed at mapping large chromosomal regions of mitotic heterochromatin in Drosophila melanogaster.

  16. Novel method to load multiple genes onto a mammalian artificial chromosome.

    Directory of Open Access Journals (Sweden)

    Anna Tóth

    Full Text Available Mammalian artificial chromosomes are natural chromosome-based vectors that may carry a vast amount of genetic material in terms of both size and number. They are reasonably stable and segregate well in both mitosis and meiosis. A platform artificial chromosome expression system (ACEs was earlier described with multiple loading sites for a modified lambda-integrase enzyme. It has been shown that this ACEs is suitable for high-level industrial protein production and the treatment of a mouse model for a devastating human disorder, Krabbe's disease. ACEs-treated mutant mice carrying a therapeutic gene lived more than four times longer than untreated counterparts. This novel gene therapy method is called combined mammalian artificial chromosome-stem cell therapy. At present, this method suffers from the limitation that a new selection marker gene should be present for each therapeutic gene loaded onto the ACEs. Complex diseases require the cooperative action of several genes for treatment, but only a limited number of selection marker genes are available and there is also a risk of serious side-effects caused by the unwanted expression of these marker genes in mammalian cells, organs and organisms. We describe here a novel method to load multiple genes onto the ACEs by using only two selectable marker genes. These markers may be removed from the ACEs before therapeutic application. This novel technology could revolutionize gene therapeutic applications targeting the treatment of complex disorders and cancers. It could also speed up cell therapy by allowing researchers to engineer a chromosome with a predetermined set of genetic factors to differentiate adult stem cells, embryonic stem cells and induced pluripotent stem (iPS cells into cell types of therapeutic value. It is also a suitable tool for the investigation of complex biochemical pathways in basic science by producing an ACEs with several genes from a signal transduction pathway of interest.

  17. Novel method to load multiple genes onto a mammalian artificial chromosome.

    Science.gov (United States)

    Tóth, Anna; Fodor, Katalin; Praznovszky, Tünde; Tubak, Vilmos; Udvardy, Andor; Hadlaczky, Gyula; Katona, Robert L

    2014-01-01

    Mammalian artificial chromosomes are natural chromosome-based vectors that may carry a vast amount of genetic material in terms of both size and number. They are reasonably stable and segregate well in both mitosis and meiosis. A platform artificial chromosome expression system (ACEs) was earlier described with multiple loading sites for a modified lambda-integrase enzyme. It has been shown that this ACEs is suitable for high-level industrial protein production and the treatment of a mouse model for a devastating human disorder, Krabbe's disease. ACEs-treated mutant mice carrying a therapeutic gene lived more than four times longer than untreated counterparts. This novel gene therapy method is called combined mammalian artificial chromosome-stem cell therapy. At present, this method suffers from the limitation that a new selection marker gene should be present for each therapeutic gene loaded onto the ACEs. Complex diseases require the cooperative action of several genes for treatment, but only a limited number of selection marker genes are available and there is also a risk of serious side-effects caused by the unwanted expression of these marker genes in mammalian cells, organs and organisms. We describe here a novel method to load multiple genes onto the ACEs by using only two selectable marker genes. These markers may be removed from the ACEs before therapeutic application. This novel technology could revolutionize gene therapeutic applications targeting the treatment of complex disorders and cancers. It could also speed up cell therapy by allowing researchers to engineer a chromosome with a predetermined set of genetic factors to differentiate adult stem cells, embryonic stem cells and induced pluripotent stem (iPS) cells into cell types of therapeutic value. It is also a suitable tool for the investigation of complex biochemical pathways in basic science by producing an ACEs with several genes from a signal transduction pathway of interest.

  18. Construction of a nurse shark (Ginglymostoma cirratum bacterial artificial chromosome (BAC library and a preliminary genome survey

    Directory of Open Access Journals (Sweden)

    Inoko Hidetoshi

    2006-05-01

    Full Text Available Abstract Background Sharks are members of the taxonomic class Chondrichthyes, the oldest living jawed vertebrates. Genomic studies of this group, in comparison to representative species in other vertebrate taxa, will allow us to theorize about the fundamental genetic, developmental, and functional characteristics in the common ancestor of all jawed vertebrates. Aims In order to obtain mapping and sequencing data for comparative genomics, we constructed a bacterial artificial chromosome (BAC library for the nurse shark, Ginglymostoma cirratum. Results The BAC library consists of 313,344 clones with an average insert size of 144 kb, covering ~4.5 × 1010 bp and thus providing an 11-fold coverage of the haploid genome. BAC end sequence analyses revealed, in addition to LINEs and SINEs commonly found in other animal and plant genomes, two new groups of nurse shark-specific repetitive elements, NSRE1 and NSRE2 that seem to be major components of the nurse shark genome. Screening the library with single-copy or multi-copy gene probes showed 6–28 primary positive clones per probe of which 50–90% were true positives, demonstrating that the BAC library is representative of the different regions of the nurse shark genome. Furthermore, some BAC clones contained multiple genes, making physical mapping feasible. Conclusion We have constructed a deep-coverage, high-quality, large insert, and publicly available BAC library for a cartilaginous fish. It will be very useful to the scientific community interested in shark genomic structure, comparative genomics, and functional studies. We found two new groups of repetitive elements specific to the nurse shark genome, which may contribute to the architecture and evolution of the nurse shark genome.

  19. Yeast artificial chromosomes employed for random assembly of biosynthetic pathways and production of diverse compounds in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Mitra Partha P

    2009-08-01

    Full Text Available Abstract Background Natural products are an important source of drugs and other commercially interesting compounds, however their isolation and production is often difficult. Metabolic engineering, mainly in bacteria and yeast, has sought to circumvent some of the associated problems but also this approach is impeded by technical limitations. Here we describe a novel strategy for production of diverse natural products, comprising the expression of an unprecedented large number of biosynthetic genes in a heterologous host. Results As an example, genes from different sources, representing enzymes of a seven step flavonoid pathway, were individually cloned into yeast expression cassettes, which were then randomly combined on Yeast Artificial Chromosomes and used, in a single transformation of yeast, to create a variety of flavonoid producing pathways. Randomly picked clones were analysed, and approximately half of them showed production of the flavanone naringenin, and a third of them produced the flavonol kaempferol in various amounts. This reflected the assembly of 5–7 step multi-species pathways converting the yeast metabolites phenylalanine and/or tyrosine into flavonoids, normally only produced by plants. Other flavonoids were also produced that were either direct intermediates or derivatives thereof. Feeding natural and unnatural, halogenated precursors to these recombinant clones demonstrated the potential to further diversify the type of molecules that can be produced with this technology. Conclusion The technology has many potential uses but is particularly suited for generating high numbers of structurally diverse compounds, some of which may not be amenable to chemical synthesis, thus greatly facilitating access to a huge chemical space in the search for new commercially interesting compounds

  20. Cloning, sequencing, and analysis of inv8 chromosome breakpoints associated with recombinant 8 syndrome.

    Science.gov (United States)

    Graw, S L; Sample, T; Bleskan, J; Sujansky, E; Patterson, D

    2000-03-01

    Rec8 syndrome (also known as "recombinant 8 syndrome" and "San Luis Valley syndrome") is a chromosomal disorder found in individuals of Hispanic descent with ancestry from the San Luis Valley of southern Colorado and northern New Mexico. Affected individuals typically have mental retardation, congenital heart defects, seizures, a characteristic facial appearance, and other manifestations. The recombinant chromosome is rec(8)dup(8q)inv(8)(p23.1q22.1), and is derived from a parental pericentric inversion, inv(8)(p23.1q22.1). Here we report on the cloning, sequencing, and characterization of the 8p23.1 and 8q22 breakpoints from the inversion 8 chromosome associated with Rec8 syndrome. Analysis of the breakpoint regions indicates that they are highly repetitive. Of 6 kb surrounding the 8p23.1 breakpoint, 75% consists of repetitive gene family members-including Alu, LINE, and LTR elements-and the inversion took place in a small single-copy region flanked by repetitive elements. Analysis of 3.7 kb surrounding the 8q22 breakpoint region reveals that it is 99% repetitive and contains multiple LTR elements, and that the 8q inversion site is within one of the LTR elements.

  1. Molecular cloning and analysis of breakpoints on ring chromosome 17 in a patient with autism.

    Science.gov (United States)

    Vazna, Alzbeta; Havlovicova, Marketa; Sedlacek, Zdenek

    2008-01-15

    The breakpoint junction on a ring chromosome 17 in a girl with autism, mental retardation, mild dysmorphism and neurofibromatosis was identified and analysed at the nucleotide level. The extent of the deleted segments was about 1.9 Mb on 17p and about 1.0 Mb on 17q. The structure of the junction between the 17p and 17q arms, especially the lack of significant homology between the juxtaposed genomic regions and the presence of short microhomology at the junction site, indicated non-homologous end joining as the most likely mechanism leading to the rearrangement. In addition to the 17p-17q junction itself, a de novo 1 kb deletion in a distance of 400 bp from the junction was identified, which arose most likely as a part of the rearrangement. The defect directly inactivated 3 genes, and the deleted terminal chromosome segments harboured 27 and 14 protein-coding genes from 17p and 17q, respectively. Several of the genes affected by the rearrangement are candidates for the symptoms observed in the patient. Additional rearrangements similar to the 1 kb deletion observed in our patient may remain undetected but can participate in the phenotype of patients with chromosomal aberrations. They can also be the reason for repeated failures to clone breakpoint junctions in other patients described in the literature.

  2. The murine ufo receptor: molecular cloning, chromosomal localization and in situ expression analysis.

    Science.gov (United States)

    Faust, M; Ebensperger, C; Schulz, A S; Schleithoff, L; Hameister, H; Bartram, C R; Janssen, J W

    1992-07-01

    We have cloned the mouse homologue of the ufo oncogene. It encodes a novel tyrosine kinase receptor characterized by a unique extracellular domain containing two immunoglobulin-like and two fibronectin type III repeats. Comparison of the predicted ufo amino acid sequences of mouse and man revealed an overall identity of 87.6%. The ufo locus maps to mouse chromosome 7A3-B1 and thereby extends the known conserved linkage group between mouse chromosome 7 and human chromosome 19. RNA in situ hybridization analysis established the onset of specific ufo expression in the late embryogenesis at day 12.5 post coitum (p.c.) and localized ufo transcription to distinct substructures of a broad spectrum of developing tissues (e.g. subepidermal cells of the skin, mesenchymal cells of the periosteum). In adult animals ufo is expressed in cells forming organ capsules as well as in connective tissue structures. ufo may function as a signal transducer between specific cell types of mesodermal origin.

  3. Construction of Agropyrum intermedium 2Ai-2 Chromosome DNA Library and Cloning of Species-Specific DNA Sequences

    Institute of Scientific and Technical Information of China (English)

    HE Cong-fen; MA You-zhi; XIN Zhi-yong; XU Qiong-fang; LI Lian-cheng

    2004-01-01

    The univalent from the meiosis-metaphase spreads of F1 (Z2× wheat variety Wan7107) was identified to be Agropyrum intermedium 2Ai-2 chromosome by GISH. The 2Ai-2 chromosomes were microisolated and collected. After two rounds of PCR amplification, the PCR products were ranged from 150 - 3 000 bp,with predominant fragments at about 200 - 2 000 bp. Using Ag.intermediumgenomic DNA as a probe, Southern blotting analysis confirmed the products originated from Ag. intermediumgenome. The products were purified, ligated to pUC18 and then transformed into competence E.coli DH5α to produce a 2Ai-2 chromosome DNA library. The microcloning experiments produced approximately 5×105 clones, the size range of the cloned inserts was 200- 1 500 bp, with an average of 580bp. Using Ag. intermediumgenomic DNA as a probe, dot blotting results showed that 56% clones are unique/low copy sequences, 44% are repetitive sequences in the library. Four Ag. intermedium clones were screened from the library by RFLP, and three clones(Mag065, Mag088, Mag139)belong to low/single sequences, one clone(Mag104)was repetitive sequence, and GISH results indicated that Mag104 was Ag.intermedium species-specific repetitive DNA sequence.

  4. Identification of region-specific yeast artificial chromosomes using pools of Alu element-mediated polymerase chain reaction probes labeled via linear amplification

    Energy Technology Data Exchange (ETDEWEB)

    Cole, C.G.; Bobrow, M.; Bentley, D.R.; Dunham, I. (United Medical and Dental Schools of Guy' s and St. Thomas Hospitals, London Bridge, London, England (United Kingdom)); Patel, K.; Shipley, J.; Sheer, D. (Imperial Cancer Research Fund, London (United Kingdom))

    1992-12-01

    The ability to identify large numbers of yeast artificial chromosomes (YACS) specific to any given genomic region rapidly and efficiently enhances both the construction of clone maps and the isolation of region-specific landmarks (e.g., polymorphic markers). The authors describe a method of preparing region-specific single-stranded hybridization probes from Alu element-mediated polymerase chain reaction (Alu-PCR) products of somatic cell hybrids for YAC library screening. Pools of up to 50 cloned Alu-PCR products from an irradiation-reduced hybrid containing 22q11.2-q13.1 were labeled to high specific activity by linear amplification using a single vector primer. The resulting single-stranded probes were extensively competed to remove repetitive sequences, while retaining the full complexity of the probe. Extensive coverage of the region by YACs using multiple probe pools was demonstrated as many YACs were detected more than once. In situ analysis using chosen YACs confirmed that the clones were specific for the region. Thus, this pooled probe approach constitutes a rapid method to identify large numbers of YACs relevant to a large chromosomal region. 29 refs., 4 figs.

  5. Identification of region-specific yeast artificial chromosomes using pools of Alu element-mediated polymerase chain reaction probes labeled via linear amplification.

    Science.gov (United States)

    Cole, C G; Patel, K; Shipley, J; Sheer, D; Bobrow, M; Bentley, D R; Dunham, I

    1992-12-01

    The ability to identify large numbers of yeast artificial chromosomes (YACs) specific to any given genomic region rapidly and efficiently enhances both the construction of clone maps and the isolation of region-specific landmarks (e.g., polymorphic markers). We describe a method of preparing region-specific single-stranded hybridization probes from Alu element-mediated polymerase chain reaction (Alu-PCR) products of somatic cell hybrids for YAC library screening. Pools of up to 50 cloned Alu-PCR products from an irradiation-reduced hybrid containing 22q11.2-q13.1 were labeled to high specific activity by linear amplification using a single vector primer. The resulting single-stranded probes were extensively competed to remove repetitive sequences, while retaining the full complexity of the probe. Extensive coverage of the region by YACs using multiple probe pools was demonstrated as many YACs were detected more than once. In situ analysis using chosen YACs confirmed that the clones were specific for the region. Thus, this pooled probe approach constitutes a rapid method to identify large numbers of YACs relevant to a large chromosomal region.

  6. Induction of genomic instability and activation of autophagy in artificial human aneuploid cells

    Energy Technology Data Exchange (ETDEWEB)

    Ariyoshi, Kentaro [Hirosaki University, Institute of Radiation Emergency Medicine, 66-1 Hon-cho, Hirosaki 036-8564 (Japan); Miura, Tomisato; Kasai, Kosuke; Fujishima, Yohei [Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki 036-8564 (Japan); Oshimura, Mitsuo [Chromosome Engineering Research Center (CERC), Tottori University, Nishicho 86, Yonago, Tottori 683-8503 (Japan); Yoshida, Mitsuaki A., E-mail: ariyoshi@hirosaki-u.ac.jp [Hirosaki University, Institute of Radiation Emergency Medicine, 66-1 Hon-cho, Hirosaki 036-8564 (Japan)

    2016-08-15

    Highlights: • Clones with artificial aneuploidy of chromosome 8 or chromosome 22 both show inhibited proliferation and genomic instability. • Increased autophagy was observed in the artificially aneuploid clones. • Inhibition of autophagy resulted in increased genomic instability and DNA damage. • Intracellular levels of reactive oxygen species were up-regulated in the artificially aneuploid clones. - Abstract: Chromosome missegregation can lead to a change in chromosome number known as aneuploidy. Although aneuploidy is a known hallmark of cancer cells, the various mechanisms by which altered gene and/or DNA copy number facilitate tumorigenesis remain unclear. To understand the effect of aneuploidy occurring in non-tumorigenic human breast epithelial cells, we generated clones harboring artificial aneuploidy using microcell-mediated chromosome transfer. Our results demonstrate that clones with artificial aneuploidy of chromosome 8 or chromosome 22 both show inhibited proliferation and genomic instability. Also, the increased autophagy was observed in the artificially aneuploidy clones, and inhibition of autophagy resulted in increased genomic instability and DNA damage. In addition, the intracellular levels of reactive oxygen species were up-regulated in the artificially aneuploid clones, and inhibition of autophagy further increased the production of reactive oxygen species. Together, these results suggest that even a single extraneous chromosome can induce genomic instability, and that autophagy triggered by aneuploidy-induced stress is a mechanism to protect cells bearing abnormal chromosome number.

  7. Microdissection and molecular manipulation of single chromosomes in woody fruit trees with small chromosomes using pomelo (Citrus grandis) as a model. II. Cloning of resistance gene analogs from single chromosomes.

    Science.gov (United States)

    Huang, D; Wu, W; Lu, L

    2004-05-01

    Amplification of resistance gene analogs (RGAs) is both a useful method for acquiring DNA markers closely linked to disease resistance (R) genes and a potential approach for the rapid cloning of R genes in plants. However, the screening of target sequences from among the numerous amplified RGAs can be very laborious. The amplification of RGAs from specific chromosomes could greatly reduce the number of RGAs to be screened and, consequently, speed up the identification of target RGAs. We have developed two methods for amplifying RGAs from single chromosomes. Method 1 uses products of Sau3A linker adaptor-mediated PCR (LAM-PCR) from a single chromosome as the templates for RGA amplification, while Method 2 directly uses a single chromosomal DNA molecule as the template. Using a pair of degenerate primers designed on the basis of the conserved nucleotide-binding-site motifs in many R genes, RGAs were successfully amplified from single chromosomes of pomelo using both these methods. Sequencing and cluster analysis of RGA clones obtained from single chromosomes revealed the number, type and organization of R-gene clusters on the chromosomes. We suggest that Method 1 is suitable for analyzing chromosomes that are unidentifiable under a microscope, while Method 2 is more appropriate when chromosomes can be clearly identified.

  8. A pathway from chromosome transfer to engineering resulting in human and mouse artificial chromosomes for a variety of applications to bio-medical challenges.

    Science.gov (United States)

    Oshimura, Mitsuo; Uno, Narumi; Kazuki, Yasuhiro; Katoh, Motonobu; Inoue, Toshiaki

    2015-02-01

    Microcell-mediated chromosome transfer (MMCT) is a technique to transfer a chromosome from defined donor cells into recipient cells and to manipulate chromosomes as gene delivery vectors and open a new avenue in somatic cell genetics. However, it is difficult to uncover the function of a single specific gene via the transfer of an entire chromosome or fragment, because each chromosome or fragment contains a set of numerous genes. Thus, alternative tools are human artificial chromosome (HAC) and mouse artificial chromosome (MAC) vectors, which can carry a gene or genes of interest. HACs/MACs have been generated mainly by either a "top-down approach" (engineered creation) or a "bottom-up approach" (de novo creation). HACs/MACs with one or more acceptor sites exhibit several characteristics required by an ideal gene delivery vector, including stable episomal maintenance and the capacity to carry large genomic loci plus their regulatory elements, thus allowing the physiological regulation of the introduced gene in a manner similar to that of native chromosomes. The MMCT technique is also applied for manipulating HACs and MACs in donor cells and delivering them to recipient cells. This review describes the lessons learned and prospects identified from studies on the construction of HACs and MACs, and their ability to drive exogenous gene expression in cultured cells and transgenic animals via MMCT. New avenues for a variety of applications to bio-medical challenges are also proposed.

  9. Molecular cloning and chromosomal localization of the ADH7 gene encoding human class IV ({sigma}) ADH

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, Hirokazu; Baraona, E.; Lieber, C.S. [Mount Sinai School of Medicine, Bronx, NY (United States)

    1996-01-15

    The ADH7 gene encoding human Class IV ({sigma}) alcohol dehydrogenase (ADH) was cloned from a Caucasian genomic DNA library and characterized. It has nine exons and eight introns that span about 22 kb, and its intron insertion is identical to that of the other ADH genes (ADH1 to ADH5). The nucleotide sequences of the exons encoding 374 amino acids are identical to the previously reported cDNA sequence of {sigma} ADH. Fluorescence in situ hybridization analysis showed that ADH7 is located on human chromosome 4q23-q24, close to the ADH cluster locus (4q21-q25). These data are consistent with the view that Class IV ADH is a member of the ADH family and is phylogenetically close to the other ADHs. 15 refs., 2 figs., 1 tab.

  10. Cloning, structural organization, and chromosomal mapping of the human phenol sulfotransferase STP2 gene

    Energy Technology Data Exchange (ETDEWEB)

    Gaedigk, A.; Beatty, B.G.; Grant, D.M. [Hospital for Sick Children, Toronto, Ontario (Canada)

    1997-03-01

    Phenol- and monoamine-metabolizing sulfotransferases (STP and STM, respectively) are members of a superfamily of enzymes that add sulfate to a variety of xenobiotics and endobiotics containing hydroxyl or amino functional groups. To characterize related sulfotransferase genes further, we used extra-long PCR (XL-PCR) to generate three distinct sizes of amplification products from human genomic DNA or from genomic phage library clones, each of which contained sulfotransferase gene sequences. One of the PCR fragments contained a new sulfotransferase gene, STP2, corresponding to a recently published cDNA clone that encodes a sulfotransferase with catalytic specificity distinct from that of the previously described STP1 and STM. Additional upstream sequence information was obtained using a second STP2-specific XL-PCR-based approach. The STP2 gene is composed of eight exons and seven introns, with exon sizes ranging from 95 to 181 bp. Protein-coding exon lengths and locations of the splice junctions were identical to those in both the STM gene and an STP2 gene published independently by another group recently. The STP2 gene maps to a chromosomal location (16p11.2-p1.2) that is the same as that previously determined for both STP1 and STM. The characterization of the STP2 gene provides further insight into the organization, regulation, and multiplicity of the sulfotransferase supergene family. 27 refs., 3 figs.

  11. Molecular cloning, chromosomal mapping, and characterization of the mouse UDP-galactose: Ceramide galactosyltransferase gene

    Energy Technology Data Exchange (ETDEWEB)

    Coetzee, T.; Fujita, N.; Marcus, J. [Univ. of North Carolina, Chapel Hill, NC (United States)] [and others

    1996-07-01

    UDP-galactose:ceramide galactosyltransferase (CGT) (EC 2.11.62) catalyzes the final step in the synthesis of galactocerebroside, a glycosphingolipid characteristically abundant in myelin. In this report, we describe the isolation of genomic clones spanning the mouse CGT gene. The mouse CGT gene consists of six exons that span a minimum of 70 kb of DNA and that encode a 541 amino acid translation product with extensive sequence similarity to the rat CGT enzyme and to UDP-glucuronosyltransferases (UGT). The 5{prime}-untranslated region of the mouse CGT gene is encoded by a separate exon located approximately 25 kb upstream of the first protein-encoding exon. Furthermore, the genomic organization of the five encoding region exons of the mouse CGT gene resembles that of the human UGT1 and rat UGT2B1 genes. Finally, analysis of somatic cell hybrids by PCR and fluorescence in situ hybridization to metaphase chromosomes has localized the mouse CGT gene to chromosome 3, bands E3-F1. 26 refs., 5 figs., 1 tab.

  12. Cloning and deletion mapping of the recF dnaN region of the Escherichia coli chromosome.

    Science.gov (United States)

    Ream, L W; Clark, A J

    1983-09-01

    By cloning a 3.6-kb EcoRI fragment of the Escherichia coli chromosome with pBR322 we located more precisely recF relative to dnaN. By deletion mapping we localized functional recF to a 1.65-kb region of the cloned fragment and allowed rough mapping of the C terminus of dnaN. Cloned recF+, separated from functional flanking genes dnaN and gyrB, complemented chromosomal recF mutations presumably by coding for a cytodiffusible product. The protein encoded by dnaN was observed as a band on a polyacrylamide gel from minicells. Identification of a recF protein was not made.

  13. Screening of YAC clones and building a map of the chromosome 13 region often deleted during chronic B-cell lymphocytic leucosis

    NARCIS (Netherlands)

    Brodyanskii, VM; Sulimova, GE; Udina, IG; Aitova, SS; Shaikhaev, GO; Sharikova, OA; Zakharev, VM; Fedorova, LI; Zelenin, AV; Eikhorn, S; Baush, C; Laland, M; Ross, M; Yankovskii, NK

    1995-01-01

    Pools of YAC clones from the ICRF library were analyzed by PCR using PBKpt, MGG15, and D13S25 markers that flank the chromosome 13 region often deleted during chronic lymphocytic leukemia. Ten clones were found and described. Nine mega-YAC clones from the CEPH library flanking the region of interest

  14. Interclonal variations in the molecular karyotype of Trypanosoma cruzi: chromosome rearrangements in a single cell-derived clone of the G strain.

    Science.gov (United States)

    Lima, Fabio Mitsuo; Souza, Renata Torres; Santori, Fábio Rinaldo; Santos, Michele Fernandes; Cortez, Danielle Rodrigues; Barros, Roberto Moraes; Cano, Maria Isabel; Valadares, Helder Magno Silva; Macedo, Andréa Mara; Mortara, Renato Arruda; da Silveira, José Franco

    2013-01-01

    Trypanosoma cruzi comprises a pool of populations which are genetically diverse in terms of DNA content, growth and infectivity. Inter- and intra-strain karyotype heterogeneities have been reported, suggesting that chromosomal rearrangements occurred during the evolution of this parasite. Clone D11 is a single-cell-derived clone of the T. cruzi G strain selected by the minimal dilution method and by infecting Vero cells with metacyclic trypomastigotes. Here we report that the karyotype of clone D11 differs from that of the G strain in both number and size of chromosomal bands. Large chromosomal rearrangement was observed in the chromosomes carrying the tubulin loci. However, most of the chromosome length polymorphisms were of small amplitude, and the absence of one band in clone D11 in relation to its reference position in the G strain could be correlated to the presence of a novel band migrating above or below this position. Despite the presence of chromosomal polymorphism, large syntenic groups were conserved between the isolates. The appearance of new chromosomal bands in clone D11 could be explained by chromosome fusion followed by a chromosome break or interchromosomal exchange of large DNA segments. Our results also suggest that telomeric regions are involved in this process. The variant represented by clone D11 could have been induced by the stress of the cloning procedure or could, as has been suggested for Leishmania infantum, have emerged from a multiclonal, mosaic parasite population submitted to frequent DNA amplification/deletion events, leading to a 'mosaic' structure with different individuals having differently sized versions of the same chromosomes. If this is the case, the variant represented by clone D11 would be better adapted to survive the stress induced by cloning, which includes intracellular development in the mammalian cell. Karyotype polymorphism could be part of the T. cruzi arsenal for responding to environmental pressure.

  15. Cloning, Structural Organization and Chromosomal Mapping of Rat Costimulatory Molecule 4-1BBL

    Institute of Scientific and Technical Information of China (English)

    Qiu-Ming DONG; Xue-Guang ZHANG; Li-Jie MA; Guang-Bo ZHANG; Ya-Fang WU; Jia-Yao SHEN; Ying CHEN; Yong-Jing CHEN; Xiang-Ke PU; Sai-Yu HANG

    2005-01-01

    4-1BBL (TNFSF9) is a member of the tumor necrosis factor (TNF) ligand superfamily, which is expressed on some activated antigen presenting cells and B cells. We isolated a rat cDNA clone encoding the rat homologue of the human 4-1BBL (GenBank accession No. AY259541). The deduced rat 4-1BBL protein, consisting of 308 amino acids with a molecular weight of 33,469 Da, was a typical type Ⅱ transmembrane glycoprotein, the same as human and murine 4-1BBL. "SDAA" in the cytoplasmic domain of rat 4-1BBL was deduced to act as the phosphorylation site for casein kinase I ("SXXS" motif), which is present in the cytoplasmic domains of human and murine 4-1BBL, and all other TNF ligand family members known to utilize reverse signaling. The two introns of 4-1BBL were also cloned (GenBank accession No.AY332409). Rat 4-1BBL is much more homologous with murine 4-1BBL than with human 4-1BBL, in both nucleotide and amino acid sequences. Rat 4-1BBL was expressed in all tested tissues: brain, lung, colon, liver,thymus, testicle, kidney, adrenal, stomach, spleen and heart. The chromosomal location of rat 4-1BBL was first identified by bioinformatics, then by fluorescence in situ hybridization at 9q11 (GenBank accession UniGene No. Rn.46783). Rat, murine and human 4-1BBL genes are evolved from a common gene. The identification and characterization of the rat counterpart of human 4-1BBL will facilitate studies of the biological function of this molecule.

  16. Cloning, tissue expression pattern, and chromosome localization of human protein kinase Bγ gene

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Protein kinase B (PKB) is a member of the second messenger-regulated subfamily of protein kinases, and plays a key role in cell-cycle regulation, glucose uptake and promotion of cell differentiation. Evidence shows that PKB undergoes activation in some human tumors and is involved in Ras pathway, which implies that PKB can trigger a pathway to induce oncogenic transformation. A nucleotide sequence of mouse Pkb? was used as a probe to screen homolog in a human liver cDNA library. A fragment of 1998 bp containing a 1440 bp ORF encoding 479 amino acid residues was obtained. Then the 3'-terminal of this fragment was extended to 2788 bp by 'electronic walking' screening, and the extended fragment was confirmed by PCR amplification. The protein deduced by the gene had a high identity of 83% and 78% to the human PKBγ and γ, respectively, and was designated as human PKB?. Northern hybridization detected two equally expressed transcripts of 8.5 and 6.5 kb in length in all 16 human tissues tested, with the highest expression level in brain, and lower levels with variation in the other tissues. By RH mapping, the PKBγ was placed on chromosome 1q43, between markers D1S304 and D1S2693. It is a valuable clue for cloning the candidate genes related to prostate cancer; Arrhythmogenic Right Ventricular Dysplasia (ARVD); Chediak-Higashi, NK cell Deficiency (CHS); and Hypoparathyrodism with Short Stature, Mental Retardation and Seizures which have already been mapped in this chromosomal region.

  17. Human phenol sulfotransferase STP2 gene: Molecular cloning, structural characterization, and chromosomal localization

    Energy Technology Data Exchange (ETDEWEB)

    Her, C.; Raftogianis, R.; Weinshilboum, R.M. [Mayo Foundation, Rochester, MN (United States)

    1996-05-01

    Sulfonation is an important pathway in the biotransformation of many drugs, xenobiotics, neurotransmitters, and steroid hormones. The thermostable (TS) form of phenol sulfotransferase (PST) preferentially catalyzes the sulfonation of {open_quotes}simple{close_quotes} planar phenols, and levels of activity of TS PST in human tissues are controlled by inheritance. Two different human liver TS PST cDNAs have been cloned that encode proteins with amino acid sequences that are 96% identical. We have determined the structure and chromosomal localization of the gene for one of these two cDNAs, STP2, as a step toward understanding molecular genetic mechanisms involved in the regulation of this enzyme activity in humans. STP2 spans approximately 5.1 kb and contains nine exons that range in length from 74 to 347 bp. The locations of most STP2 exon-intron splice junctions are identical to those of a gene for the thermolabile form of PST in humans, STM; a rat PST gene; a human estrogen ST (EST) gene, STE; and a guinea pig EST gene. The two initial STP2 exons, IA and IB, were identified by performing 5{prime}-rapid amplification of cDNA ends with human liver cDNA as template. Exons IA and IB are noncoding and represent two different human liver TS PST cDNA 5{prime}untranslated region sequences. The two apparent 5{prime}-ons IA and IB, contain no canonical TATA boxes, but do contain CCAAT elements. STP2 was localized to human chromosome 16 by performing the PCR with DNA from NIGMS human/rodent somatic cell hybrids as template. Structural characterization of STP2 will make it possible to begin to study molecular genetic mechanisms involved in the regulation of TS PST activity in human tissues. 63 refs., 7 figs., 1 tab.

  18. Improving the comparative map of SSC2p-q13 by sample sequencing of BAC clones

    NARCIS (Netherlands)

    Rattink, A.P.; Jungerius, B.J.; Faivre, M.; Chardon, P.; Harlizius, B.; Groenen, M.A.M.

    2001-01-01

    To improve the comparative map for pig chromosome 2 and increase the gene density on this chromosome, a porcine bacterial artificial chromosome (BAC) library was screened with 17 microsatellite markers and 18 genes previously assigned to pig chromosome 2. Fifty-one BAC clones located in the region o

  19. An easy and versatile 2-step protocol for targeted modification and subcloning of DNA from bacterial artificial chromosomes using non-commercial plasmids

    Directory of Open Access Journals (Sweden)

    Hartwich Heiner

    2012-03-01

    Full Text Available Abstract Background Promoter-specific expression of foreign DNA in transgenic organisms often relies on bacterial artificial chromosomes (BACs. This approach requires modification and subcloning of BAC-DNA by recombineering technologies in Escherichia coli. Most current protocols rely on commercial kits or isolation of BACs, their transfer between different host strains, and their restriction. Findings In this report we present a 2-step protocol for efficient modification and subcloning of DNA from bacterial artificial chromosomes using the non-commercial plasmids pKM208 and pTP223, distributed from addgene.com. A targeting cassette was successfully integrated into a BAC and 42 kb of this construct were subcloned. Both a plasmid-derived substrate with longer homology arms and a PCR-generated substrate with short homology arms (50 bp were used for recombination. pKM208 and pTP223 contain all required genes for recombineering, but differ in their antibiotic resistance genes. This makes the system independent of the selection markers on the DNA molecules targeted for recombination. Conclusions The time and cost saving protocol presented here compares favorably to currently used systems. Using non-commercial plasmids, it allows targeted modification and cloning of large DNA (> 40 kb fragments in vivo without restriction and ligation. Furthermore, both steps are performed in the same host eliminating the need to isolate BAC DNA and to use different bacterial strains.

  20. cDNA cloning, sequence analysis, and chromosomal localization of the gene for human carnitine palmitoyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Finocchiaro, G.; Taroni, F.; Martin, A.L.; Colombo, I.; Tarelli, G.T.; DiDonato, S. (Istituto Nazionale Neurologico C. Besta, Milan (Italy)); Rocchi, M. (Istituto G. Gaslini, Genoa (Italy))

    1991-01-15

    The authors have cloned and sequenced a cDNA encoding human liver carnitine palmitoyltransferase an inner mitochondrial membrane enzyme that plays a major role in the fatty acid oxidation pathway. Mixed oligonucleotide primers whose sequences were deduced from one tryptic peptide obtained from purified CPTase were used in a polymerase chain reaction, allowing the amplification of a 0.12-kilobase fragment of human genomic DNA encoding such a peptide. A 60-base-pair (bp) oligonucleotide synthesized on the basis of the sequence from this fragment was used for the screening of a cDNA library from human liver and hybridized to a cDNA insert of 2255 bp. This cDNA contains an open reading frame of 1974 bp that encodes a protein of 658 amino acid residues including 25 residues of an NH{sub 2}-terminal leader peptide. The assignment of this open reading frame to human liver CPTase is confirmed by matches to seven different amino acid sequences of tryptic peptides derived from pure human CPTase and by the 82.2% homology with the amino acid sequence of rat CPTase. The NH{sub 2}-terminal region of CPTase contains a leucine-proline motif that is shared by carnitine acetyl- and octanoyltransferases and by choline acetyltransferase. The gene encoding CPTase was assigned to human chromosome 1, region 1q12-1pter, by hybridization of CPTase cDNA with a DNA panel of 19 human-hanster somatic cell hybrids.

  1. Yeast artificial chromosome contigs reveal that distal variable-region genes reside at least 3 megabases from the joining regions in the murine immunoglobulin kappa locus.

    Science.gov (United States)

    George, J B; Li, S; Garrard, W T

    1995-01-01

    The immunoglobulin kappa gene locus encodes 95% of the light chains of murine antibody molecules and is thought to contain up to 300 variable (V kappa)-region genes generally considered to comprise 20 families. To delineate the locus we have isolated 29 yeast artificial chromosome genomic clones that form two contigs, span > 3.5 megabases, and contain two known non-immunoglobulin kappa markers. Using PCR primers specific for 19 V kappa gene families and Southern analysis, we have refined the genetically defined order of these V kappa gene families. Of these, V kappa 2 maps at least 3.0 Mb from the joining (J kappa) region and appears to be the most distal V kappa gene segment. Images Fig. 3 Fig. 4 PMID:8618913

  2. Efficient generation of recombinant RNA viruses using targeted recombination-mediated mutagenesis of bacterial artificial chromosomes containing full-length cDNA

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Risager, Peter Christian; Fahnøe, Ulrik

    2013-01-01

    . This strategy allows manipulation of viral cDNA by targeted recombination-mediated mutagenesis within bacteria. Results A new CSFV-BAC (pBeloR26) derived from the Riems vaccine strain has been constructed and subsequently modified in the E2 coding sequence, using the targeted recombination strategy to enable......Background Infectious cDNA clones are a prerequisite for directed genetic manipulation of RNA viruses. Here, a strategy to facilitate manipulation and rescue of classical swine fever viruses (CSFVs) from full-length cDNAs present within bacterial artificial chromosomes (BACs) is described...... recombination-mediated mutagenesis provides a powerful tool for expediting the construction of novel RNA genomes and should be applicable to the manipulation of other RNA viruses....

  3. 白眉长臂猿基因组BAC文库的构建%Construction of Genome Bacterial Artificial Chromosome Library of Hylobates Hoolock

    Institute of Scientific and Technical Information of China (English)

    王起明; 孙烨超; 厉申捷; 叶建平

    2015-01-01

    High quality genomic DNA of Hylobates hoolock was obtained by gentle physical homogenization. The DNA was partially digested with EcoRⅠand EcoRⅠmethylase, and cloned to pCC1BAC vector. The positive clones were stored in 384-well plates. The constructed BAC library consists of 85800 clones. DNA from randomly selected 250 BAC clones was restricted with Not I restriction enzyme and fragments were separated by pulsed field gel electrophoresis. The result shows that the average insert size is estimated as approximately 110 kb, and the ratio of non-recombinant clones is 10. 0%. If the genome size of Hylobates hoolock is 3 ×106 kilo-base, the library could cover 3 times the number of genome.%通过温和的物理方法获得白眉长臂猿高质量的基因组DNA,EcoRⅠ和EcoRⅠ甲基化酶部分酶切后经回收、连接、转化、阳性克隆的保存,构建了含有85800个克隆的全基因组BAC( Bacterial artificial chromosome)文库.随机选取250个BAC克隆进行Not I酶切及脉冲场电泳分析,结果表明该文库的平均插入片段大小为110 kb,非重组克隆(无插入片段)的比率为10.0%.假定白眉长臂猿的基因组大小为3×106 kb,根据文库的平均插入片段大小,则该文库具有3倍的基因组覆盖率.

  4. The Selection and Use of Sorghum (Sorghum propinquum Bacterial Artificial Chromosomes as Cytogenetic FISH Probes for Maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Debbie M. Figueroa

    2011-01-01

    Full Text Available The integration of genetic and physical maps of maize is progressing rapidly, but the cytogenetic maps lag behind, with the exception of the pachytene fluorescence in situ hybridization (FISH maps of maize chromosome 9. We sought to produce integrated FISH maps of other maize chromosomes using Core Bin Marker loci. Because these 1 Kb restriction fragment length polymorphism (RFLP probes are below the FISH detection limit, we used BACs from sorghum, a small-genome relative of maize, as surrogate clones for FISH mapping. We sequenced 151 maize RFLP probes and compared in silico BAC selection methods to that of library filter hybridization and found the latter to be the best. BAC library screening, clone verification, and single-clone selection criteria are presented along with an example of transgenomic BAC FISH mapping. This strategy has been used to facilitate the integration of RFLP and FISH maps in other large-genome species.

  5. The selection and use of sorghum (Sorghum propinquum) bacterial artificial chromosomes as cytogenetic FISH probes for maize (Zea mays L.).

    Science.gov (United States)

    Figueroa, Debbie M; Davis, James D; Strobel, Cornelia; Conejo, Maria S; Beckham, Katherine D; Ring, Brian C; Bass, Hank W

    2011-01-01

    The integration of genetic and physical maps of maize is progressing rapidly, but the cytogenetic maps lag behind, with the exception of the pachytene fluorescence in situ hybridization (FISH) maps of maize chromosome 9. We sought to produce integrated FISH maps of other maize chromosomes using Core Bin Marker loci. Because these 1 Kb restriction fragment length polymorphism (RFLP) probes are below the FISH detection limit, we used BACs from sorghum, a small-genome relative of maize, as surrogate clones for FISH mapping. We sequenced 151 maize RFLP probes and compared in silico BAC selection methods to that of library filter hybridization and found the latter to be the best. BAC library screening, clone verification, and single-clone selection criteria are presented along with an example of transgenomic BAC FISH mapping. This strategy has been used to facilitate the integration of RFLP and FISH maps in other large-genome species.

  6. A gene expression atlas of the central nervous system based on bacterial artificial chromosomes.

    Science.gov (United States)

    Gong, Shiaoching; Zheng, Chen; Doughty, Martin L; Losos, Kasia; Didkovsky, Nicholas; Schambra, Uta B; Nowak, Norma J; Joyner, Alexandra; Leblanc, Gabrielle; Hatten, Mary E; Heintz, Nathaniel

    2003-10-30

    The mammalian central nervous system (CNS) contains a remarkable array of neural cells, each with a complex pattern of connections that together generate perceptions and higher brain functions. Here we describe a large-scale screen to create an atlas of CNS gene expression at the cellular level, and to provide a library of verified bacterial artificial chromosome (BAC) vectors and transgenic mouse lines that offer experimental access to CNS regions, cell classes and pathways. We illustrate the use of this atlas to derive novel insights into gene function in neural cells, and into principal steps of CNS development. The atlas, library of BAC vectors and BAC transgenic mice generated in this screen provide a rich resource that allows a broad array of investigations not previously available to the neuroscience community.

  7. Diagnosis and Prognostication of Ductal Adenocarcinomas of the Pancreas Based on Genome-Wide DNA Methylation Profiling by Bacterial Artificial Chromosome Array-Based Methylated CpG Island Amplification

    Directory of Open Access Journals (Sweden)

    Masahiro Gotoh

    2011-01-01

    Full Text Available To establish diagnostic criteria for ductal adenocarcinomas of the pancreas (PCs, bacterial artificial chromosome (BAC array-based methylated CpG island amplification was performed using 139 tissue samples. Twelve BAC clones, for which DNA methylation status was able to discriminate cancerous tissue (T from noncancerous pancreatic tissue in the learning cohort with a specificity of 100%, were identified. Using criteria that combined the 12 BAC clones, T-samples were diagnosed as cancers with 100% sensitivity and specificity in both the learning and validation cohorts. DNA methylation status on 11 of the BAC clones, which was able to discriminate patients showing early relapse from those with no relapse in the learning cohort with 100% specificity, was correlated with the recurrence-free and overall survival rates in the validation cohort and was an independent prognostic factor by multivariate analysis. Genome-wide DNA methylation profiling may provide optimal diagnostic markers and prognostic indicators for patients with PCs.

  8. Human artificial chromosome assembly by transposon-based retrofitting of genomic BACs with synthetic alpha-satellite arrays.

    Science.gov (United States)

    Basu, Joydeep; Willard, Huntington F; Stromberg, Gregory

    2007-01-01

    The development of methodologies for the rapid assembly of synthetic alpha-satellite arrays recapitulating the higher-order periodic organization of native human centromeres permits the systematic investigation of the significance of primary sequence and sequence organization in centromere function. Synthetic arrays with defined mutations affecting sequence and/or organization may be evaluated in a de novo human artificial chromosome assay. This unit describes strategies for the assembly of custom built alpha-satellite arrays containing any desired mutation as well as strategies for the construction and manipulation of alpha satellite-based transposons. Transposons permit the rapid and reliable retrofitting of any genomic bacterial artificial chromosome (BAC) with synthetic alpha-satellite arrays and other functional components, thereby facilitating conversion into BAC-based human artificial chromosome vectors. These techniques permit identification and optimization of the critical parameters underlying the unique ability of alpha-satellite DNA to facilitate de novo centromere assembly, and they will establish the foundation for the next generation of human artificial chromosome vectors.

  9. Mapping and ordered cloning of the human X chromosome. Progress report, September 1991--November 1992

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, C.T.; Nelson, D.L.

    1992-12-01

    Progress is reported on gathering X chromosome specific libraries and integrating those with the library produced in this project. Further studies on understanding Fragile X Syndrome and other hereditary diseases related to the X chromosome are described. (DT)

  10. Mammalian DNA ligase III: Molecular cloning, chromosomal localization, and expression in spermatocytes undergoing meiotic recombination

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jingwen; Danehower, S.; Besterman, J.M.; Husain, I. [Glaxo Research Inst., Research Triangle Park, NC (United States)] [and others

    1995-10-01

    Three biochemically distinct DNA ligase activities have been identified in mammalian cell extracts. We have recently purified DNA ligase II and DNA ligase III to near homogeneity from bovine liver and testis tissue, respectively. Amino acid sequencing studies indicated that these enzymes are encoded by the same gene. In the present study, human and murine cDNA clones encoding DNA ligase III were isolated with probes based on the peptide sequences. The human DNA ligase III cDNA encodes a polypeptide of 862 amino acids, whose sequence is more closely related to those of the DNA ligases encoded by poxviruses than to replicative DNA ligases, such as human DNA ligase I. In vitro transcription and translation of the cDNA produced a catalytically active DNA ligase similar in size and substrate specificity to the purified bovine enzyme. The DNA ligase III gene was localized to human chromosome 17, which eliminated this gene as a candidate for the cancer-prone disease Bloom syndrome that is associated with DNA joining abnormalities. DNA ligase III is ubiquitously expressed at low levels, except in the testes, in which the steady-state levels of DNA ligase III mRNA are at least 10-fold higher than those detected in other tissues and cells. Since DNA ligase I mRNA is also present at high levels in the testes, we examined the expression of the DNA ligase genes during spermatogenesis. DNA ligase I mRNA expression correlated with the contribution of proliferating supermatogonia cells to the testes, in agreement with the previously defined role of this enzyme in DNA replications. In contrast, elevated levels of DNA ligase III mRNA were observed in primary supermatocytes undergoing recombination prior to the first meiotic division. Therefore, we suggest that DNA ligase III seals DNA strand breaks that arise during the process of meiotic recombination in germ cells and as a consequence of DNA damage in somatic cells. 62 refs., 7 figs.

  11. Transformation of Azotobacter vinelandii OP with a broad host range plasmid containing a cloned chromosomal nif-DNA marker.

    Science.gov (United States)

    Bingle, W H

    1988-05-01

    The non-nitrogen-fixing (Nif-) strain UW10 of Azotobacter vinelandii OP (UW) was naturally induced to competence and transformed with broad host range plasmid pKT210 containing the cloned wild-type nif-10 locus from A. vinelandii UW (Nif+); this marker was unable to complement the nif-10 mutation in trans, but could through recombination with the chromosome. The most frequent type of transformation event observed was recombination between the homologous regions of the plasmid and chromosome (producing Nif+ transformants) with loss of the plasmid vector. At a substantially lower frequency, transformants expressing the plasmid-encoded antibiotic resistance determinants were isolated which were phenotypically Nif-. Agarose gel electrophoresis showed that these transformants contained a plasmid migrating with the same mobility as the original donor plasmid. During culture these transformants acquired a Nif+ phenotype without the loss of the plasmid, as judged by the use of a hybridization probe specific for the cloned nif-DNA fragment. These data indicate that plasmids carrying sequences homologous to chromosomal sequences could be maintained in recombination-proficient A. vinelandii UW. The introduction of plasmids containing sequences homologous to chromosomal sequences was facilitated by prelinearization of the plasmid using a restriction endonuclease generating cohesive ends. Because the site of linearization could be chosen outside the region of shared homology, it was unlikely that the route of plasmid establishment occurred via a homology-facilitated transformation mechanism. The data also indicated that A. vinelandii UW could harbor broad host range cloning vectors based on plasmid RSF1010 without significant impairment of its nitrogen-fixation ability.

  12. Construction and characterization of two bacterial artificial chromosome libraries of pea (Pisum sativum L.) for the isolation of economically important genes.

    Science.gov (United States)

    Coyne, C J; McClendon, M T; Walling, J G; Timmerman-Vaughan, G M; Murray, S; Meksem, K; Lightfoot, D A; Shultz, J L; Keller, K E; Martin, R R; Inglis, D A; Rajesh, P N; McPhee, K E; Weeden, N F; Grusak, M A; Li, C-M; Storlie, E W

    2007-09-01

    Pea (Pisum sativum L.) has a genome of about 4 Gb that appears to share conserved synteny with model legumes having genomes of 0.2-0.4 Gb despite extensive intergenic expansion. Pea plant inventory (PI) accession 269818 has been used to introgress genetic diversity into the cultivated germplasm pool. The aim here was to develop pea bacterial artificial chromosome (BAC) libraries that would enable the isolation of genes involved in plant disease resistance or control of economically important traits. The BAC libraries encompassed about 3.2 haploid genome equivalents consisting of partially HindIII-digested DNA fragments with a mean size of 105 kb that were inserted in 1 of 2 vectors. The low-copy oriT-based T-DNA vector (pCLD04541) library contained 55 680 clones. The single-copy oriS-based vector (pIndigoBAC-5) library contained 65 280 clones. Colony hybridization of a universal chloroplast probe indicated that about 1% of clones in the libraries were of chloroplast origin. The presence of about 0.1% empty vectors was inferred by white/blue colony plate counts. The usefulness of the libraries was tested by 2 replicated methods. First, high-density filters were probed with low copy number sequences. Second, BAC plate-pool DNA was used successfully to PCR amplify 7 of 9 published pea resistance gene analogs (RGAs) and several other low copy number pea sequences. Individual BAC clones encoding specific sequences were identified. Therefore, the HindIII BAC libraries of pea, based on germplasm accession PI 269818, will be useful for the isolation of genes underlying disease resistance and other economically important traits.

  13. Chromosome

    Science.gov (United States)

    Chromosomes are structures found in the center (nucleus) of cells that carry long pieces of DNA. DNA ... is the building block of the human body. Chromosomes also contain proteins that help DNA exist in ...

  14. Integration of the cytogenetic, genetic, and physical maps of the human genome by FISH mapping of CEPH YAC clones

    Energy Technology Data Exchange (ETDEWEB)

    Bray-Ward, P.; Menninger, J.; Lieman, J. [Yale Univ. School of Medicine, New Haven, CT (United States)] [and others

    1996-02-15

    This article discusses the genetic mapping of over 950 yeast artificial chromosome (YAC) clones on human chromosomes. This integration of the cytogenetic, genetic and physical maps of the human genome was accomplished using fluorescence in situ hybridization (FISH) mapping and the CEPH library of YAC clones. 27 refs., 2 figs., 1 tab.

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

    Science.gov (United States)

    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...

  16. Cloning

    Science.gov (United States)

    ... copies of whole animals Therapeutic cloning, which creates embryonic stem cells. Researchers hope to use these cells to grow healthy tissue to replace injured or diseased tissues in the human body. NIH: National Human Genome Research Institute

  17. A bacterial artificial chromosome transgenic mouse model for visualization of neurite growth.

    Science.gov (United States)

    Tao, Tao; Chen, Chen; Sun, Jie; Peng, YaJing; Zhu, MinSheng

    2015-04-01

    Class III β-tubulin (Tubb3) is a component of the microtubules in neurons and contributes to microtubule dynamics that are required for axon outgrowth and guidance during neuronal development. We here report a novel bacterial artificial chromosome (BAC) transgenic mouse line that expresses Class III β-tubulin fused to mCherry, an improved monomeric red fluorescent protein, for the visualization of microtubules during neuronal development. A BAC containing Tubb3 gene was modified by insertion of mCherry complementary DNA downstream of Tubb3 coding sequence via homologous recombination. mCherry fusion protein was expressed in the nervous system and testis of the transgenic animal, and the fluorescent signal was observed in the neurons that located in the olfactory bulb, cerebral cortex, hippocampal formation, cerebellum, as well as the retina. Besides, Tubb3-mCherry fusion protein mainly distributed in neurites and colocalized with endogenous Class III β-tubulin. The fusion protein labels Purkinje cell dendrites during cerebellar circuit formation. Therefore, this transgenic line might be a novel tool for scientific community to study neuronal development both in vitro and in vivo.

  18. Integration-free iPS cells engineered using human artificial chromosome vectors.

    Directory of Open Access Journals (Sweden)

    Masaharu Hiratsuka

    Full Text Available Human artificial chromosomes (HACs have unique characteristics as gene-delivery vectors, including episomal transmission and transfer of multiple, large transgenes. Here, we demonstrate the advantages of HAC vectors for reprogramming mouse embryonic fibroblasts (MEFs into induced pluripotent stem (iPS cells. Two HAC vectors (iHAC1 and iHAC2 were constructed. Both carried four reprogramming factors, and iHAC2 also encoded a p53-knockdown cassette. iHAC1 partially reprogrammed MEFs, and iHAC2 efficiently reprogrammed MEFs. Global gene expression patterns showed that the iHACs, unlike other vectors, generated relatively uniform iPS cells. Under non-selecting conditions, we established iHAC-free iPS cells by isolating cells that spontaneously lost iHAC2. Analyses of pluripotent markers, teratomas and chimeras confirmed that these iHAC-free iPS cells were pluripotent. Moreover, iHAC-free iPS cells with a re-introduced HAC encoding Herpes Simplex virus thymidine kinase were eliminated by ganciclovir treatment, indicating that the HAC safeguard system functioned in iPS cells. Thus, the HAC vector could generate uniform, integration-free iPS cells with a built-in safeguard system.

  19. Natural - synthetic - artificial!

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  20. CHARACTERIZATION AND CHROMOSOMAL ASSIGNMENT OF YEAST ARTIFICIAL CHROMOSOMES CONTAINING HUMAN 3P13-P21-SPECIFIC SEQUENCE-TAGGED SITES

    NARCIS (Netherlands)

    MICHAELIS, SC; BARDENHEUER, W; LUX, A; SCHRAMM, A; GOCKEL, A; SIEBERT, R; WILLERS, C; SCHMIDTKE, K; TODT, B; VANDERHOUT, AH; BUYS, CHCM; HEPPELLPARTON, AC; RABBITTS, PH; UNGAR, S; SMITH, D; LEPASLIER, D; COHEN, D; OPALKA, B; SCHUTTE, J

    1995-01-01

    Human chromosomal region 3p12-p23 is proposed to harbor at least three tumor suppressor genes involved in the development of lung cancer, renal cell carcinoma, and other neoplasias. In order to identify one of these genes we defined sequence tagged sites (STSs) specific for 3p13-p24.2 by analyzing a

  1. Molecular cloning and chromosomal localization of the nucleic acid sequences encoding the cerebrovascular and plaque amyloid peptide

    Energy Technology Data Exchange (ETDEWEB)

    Robakis, N.K.; Ramakrishna, N.; Wolfe, G.; Wisniewski, H.M.

    1987-05-01

    Amyloid deposits in vessels and neuritic plaques are found in large numbers in the brains of Alzheimer's Disease (AD) and adult Downs Syndrome (DS) patients. The partial amino acid sequence of the amyloid peptide has been determined. They used this amino acid sequence to synthesize an oligonucleotide probe specific for the amyloid peptide gene. Screening of a human brain cDNA library with this probe, yielded a clone which contained an insert 1.8 kb. This clone contains a long open reading frame including a region which encodes the 28 amino acids of the amyloid peptide. Northern blots of human brain mRNA detected a transcript of 3.3 kb long which hybridized to their cDNA clone. A similar mRNA was detected in the hamster, mouse, sheep and rabbit brains. Southern blots under stringent hybridization conditions detected sequences homologous to the amyloid gene in the genomes of hamster, mouse, sheep and rabbit suggesting that this gene has been conserved during mammalian evolution. Hybridization under reduced stringency revealed the presence of additional sequences related to the amyloid gene in the genome of the above organisms. Hybridization analysis of human x chinese hamster cell lines DNA showed that the gene encoding the amyloid peptide is located on chromosome 21, suggesting a genetic relationship between AD and DS.

  2. Cloning of genomic DNA of rice 5-enolpyruvylshikimate 3-phosphate synthase gene and chromosomal localization of the gene

    Institute of Scientific and Technical Information of China (English)

    徐军望; 冯德江; 李旭刚; 常团结; 朱祯

    2002-01-01

    The shikimate pathway enzyme 5-enolpyruvylshikimate 3-phosphate synthase (EPSPs) is the target of nonselective herbicide glyphosate. A partial rice epsps cDNA was generated by RT-PCR with primers designed according to EST sequence in GenBank and used as probe for rice genomic library screening. In a screen of approximately 8.0×104 clones from the rice genomic library, sixteen positive clones were obtained, which strongly hybridized to the probe. One clone, E11, was selected for further analysis and the full-length 3661 bp rice epsps genomic sequence was obtained. Sequence analysis and homologous comparison revealed that epsps gene is composed of 8 exons and 7 introns. Analysis by restriction fragment length polymorphism with the probe of rice epsps cDNA fragment confirmed that rice epsps is located on chromosome 6 with an indica-japonica (ZYQ8-JX17) double-haploid (DH) population. This is the first report on the EPSP synthase from monocotyledons.

  3. Identification of 2nd chromosome region translocated onto the W chromosome by RFLP with EST-cDNA clones in the Gensei-kouken strains of the mulberry silkworm, Bombyx mori L

    Directory of Open Access Journals (Sweden)

    Sivaramakurup Sreekumar

    2010-01-01

    Full Text Available In silkworms, sex-limited strains are either obtained spontaneously or induced by X-rays or gamma rays. When a fragment of an autosome carrying a dominant allele of those genes responsible for certain characters is translocated onto a W chromosome, the female of the successive generations will express these phenotypic characters and sex discrimination can be facilitated. Gensei-kouken strains are sex-limited strains of silkworms developed by irradiating the pupae with gamma rays, by which a portion of the second chromosome is translocated onto the W chromosome. In these improved strains, the females are yellow-blooded and spin yellow cocoons. By using the EST-cDNA clones mapped on the Z chromosome, we identified the sex according to the polymorphic banding pattern or intensity of the signals. Furthermore, by using the clones on the second chromosome, the region of the second chromosome translocated onto the W chromosome was also defined. In both the A95 and A 96 strains selected for the present study, only the mid-portion of the second chromosome was translocated. The differences in length of the fragments translocated in these strains are discussed.

  4. Dysregulation of gene expression in the artificial human trisomy cells of chromosome 8 associated with transformed cell phenotypes.

    Directory of Open Access Journals (Sweden)

    Hisakatsu Nawata

    Full Text Available A change in chromosome number, known as aneuploidy, is a common characteristic of cancer. Aneuploidy disrupts gene expression in human cancer cells and immortalized human epithelial cells, but not in normal human cells. However, the relationship between aneuploidy and cancer remains unclear. To study the effects of aneuploidy in normal human cells, we generated artificial cells of human primary fibroblast having three chromosome 8 (trisomy 8 cells by using microcell-mediated chromosome transfer technique. In addition to decreased proliferation, the trisomy 8 cells lost contact inhibition and reproliferated after exhibiting senescence-like characteristics that are typical of transformed cells. Furthermore, the trisomy 8 cells exhibited chromosome instability, and the overall gene expression profile based on microarray analyses was significantly different from that of diploid human primary fibroblasts. Our data suggest that aneuploidy, even a single chromosome gain, can be introduced into normal human cells and causes, in some cases, a partial cancer phenotype due to a disruption in overall gene expression.

  5. Cloning and characterization of chromosomal markers in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Yu, Feng; Lei, Yunting; Li, Yuan; Dou, Quanwen; Wang, Haiqing; Chen, Zhiguo

    2013-07-01

    Eleven tandemly repetitive sequences were identified from a Cot-1 library by FISH and sequence analysis of alfalfa (Medicago sativa). Five repetitive sequences (MsCR-1, MsCR-2, MsCR-3, MsCR-4, and MsCR-5) were centromeric or pericentromeric, of which three were satellite DNAs and two were minisatellite DNAs. Monomers of 144, 148, and 168 bp were identified in MsCR-1, MsCR-2, and MsCR-3, respectively, while 15 and 39 bp monomers were identified in MsCR-4 and MsCR-5, respectively. Three repetitive sequences were characterized as subtelomeric; one repetitive sequence, MsTR-1, had a 184 bp monomer, and two repetitive sequences had fragments of 204 and 327 bp. Sequence analysis revealed homology (70-80 %) between MsTR-1 and a highly repeated sequence (C300) isolated from M. ssp. caerulea. Three identified repetitive sequences produced hybridization signals at multiple sites in a few of the chromosomes; one repetitive sequence was identified as the E180 satellite DNA previously isolated from M. sativa, while the other 163 and 227 bp fragments had distinct sequences. Physical mapping of the repetitive sequences with double-target FISH revealed different patterns. Thus, nine novel tandemly repetitive sequences that can be adopted as distinct chromosome markers in alfalfa were identified in this study. Furthermore, the chromosome distribution of each sequence was well described. Though significant chromosome variations were detected within and between cultivars, a molecular karyotype of alfalfa was suggested with the chromosome markers we identified. Therefore, these novel chromosome markers will still be a powerful tool for genome composition analysis, phylogenetic studies, and breeding applications.

  6. Construction of BAC libraries from flow-sorted chromosomes

    OpenAIRE

    Šafář, J.; Šimková, H; Doležel, J

    2016-01-01

    Cloned DNA libraries in bacterial artificial chromosome (BAC) are the most widely used form of large-insert DNA libraries. BAC libraries are typically represented by ordered clones derived from genomic DNA of a particular organism. In the case of large eukaryotic genomes, whole-genome libraries consist of a hundred thousand to a million clones, which make their handling and screening a daunting task. The labor and cost of working with whole-genome libraries can be greatly reduced by construct...

  7. Narrowing the genetic interval and yeast artificial chromosome map in the branchio-oto-renal region on chromosome 8q

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Shrawan; Kimberling, W.J.; Pinnt, J. [Boys Town National Research Hospital, Omaha, NE (United States)] [and others

    1996-01-01

    Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by branchial abnormality, hearing loss, and renal anomalies. Recently, the disease gene has been localized to chromosome 8q. Here, we report genetic studies that further refine the disease gene region to a smaller interval and identify several YACs from the critical region. We studied two large, clinically well-characterized BOR families with a set of 13 polymorphic markers spanning the D8S165-D8S275 interval from the chromosome 8q region. Based on multipoint analysis, the highest likelihood for the location of the BOR gene is between markers D8S543 and D8S530, a distance of about 2 cM. YACs that map in the BOR critical region have been identified and characterized by fluorescence in situ hybridization and pulsed-field gel electrophoresis. A YAC contig, based on the STS content map, that covers a minimum of 4 Mb of human DNA in the critical region of BOR is assembled. This lays the groundwork for the construction of a transcriptional map of this region and the eventual identification of genes involved in BOR syndrome. 40 refs., 4 figs., 1 tab.

  8. Telomere length homeostasis and telomere position effect on a linear human artificial chromosome are dictated by the genetic background.

    Science.gov (United States)

    Weuts, An; Voet, Thierry; Verbeeck, Jelle; Lambrechts, Nathalie; Wirix, Evelyne; Schoonjans, Luc; Danloy, Sophie; Marynen, Peter; Froyen, Guy

    2012-12-01

    Telomere position effect (TPE) is the influence of telomeres on subtelomeric epigenetic marks and gene expression. Previous studies suggested that TPE depends on genetic background. As these analyses were performed on different chromosomes, cell types and species, it remains unclear whether TPE represents a chromosome-rather than genetic background-specific regulation. We describe the development of a Linear Human Artificial Chromosome (L-HAC) as a new tool for telomere studies. The L-HAC was generated through the Cre-loxP-mediated addition of telomere ends to an existing circular HAC (C-HAC). As it can be transferred to genetically distinct cell lines and animal models the L-HAC enables the study of TPE in an unprecedented manner. The HAC was relocated to four telomerase-positive cell lines via microcell-mediated chromosome transfer and subsequently to mice via blastocyst injection of L-HAC(+)-ES-cells. We could show consistent genetic background-dependent adaptation of telomere length and telomere-associated de novo subtelomeric DNA methylation in mouse ES-R1 cells as well as in mice. Expression of the subtelomeric neomycin gene was inversely correlated with telomere length and subtelomeric methylation. We thus provide a new tool for functional telomere studies and provide strong evidence that telomere length, subtelomeric chromatin marks and expression of subtelomeric genes are genetic background dependent.

  9. Cloning, chromosomal localization, SNP detection and association analysis of the porcine IRS-1 gene.

    Science.gov (United States)

    Niu, P-X; Huang, Z; Li, C-C; Fan, B; Li, K; Liu, B; Yu, M; Zhao, S-H

    2009-11-01

    Insulin receptor substrate-1(IRS-1) gene is one member of the Insulin receptor substrate (IRS) gene family, which plays an important role in mediating the growth of skeletal muscle and the molecular metabolism of type 2 diabetes. Here, we cloned a 3,573 bp fragment of the partial CDS sequence of porcine IRS-1 gene by in silicon cloning strategy and RT-PCR method. The porcine IRS-1 gene was assigned to SSC15q25 by using IMpRH. Sequencing of PCR products from Duroc and Tibetan pig breeds identified one SNP in exon 1 of porcine IRS-1 gene (C3257A polymorphisms). Association analysis of genotypes with the growth traits, anatomy traits, meat quality traits and physiological biochemical indexes traits showed that different genotypes at locus 3,257 of IRS-1 have significant differences in carcass straight length in pigs (P = 0.0102 \\ 0.05).

  10. Porcine gamma-synuclein: molecular cloning, expression analysis, chromosomal localization and functional expression

    DEFF Research Database (Denmark)

    Frandsen, Pernille Munk; Madsen, Lone Bruhn; Bendixen, Christian

    2009-01-01

    which shows a high similarity to bovine (90%), human (87%) and mouse (83%) γ-synuclein. A genomic clone containing the entire porcine SNCG gene was isolated and its genomic organization determined. The gene is composed of five exons, the general structure being observed to be very similar...... reports the cloning and characterization of the porcine (Sus scrofa) γ-synuclein cDNA (SNCG). The SNCG cDNA was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) using oligonucleotide primers derived from in silico sequences. The porcine SNCG cDNA codes for a protein of 126 amino acids...... to that of the human SNCG gene. Expression analysis by quantitative real-time RT-PCR revealed the presence of SNCG transcripts in all examined organs and tissues. Differential expression was observed, with very high levels of SNCG mRNA in fat tissue and high expression levels in spleen, cerebellum, frontal cortex...

  11. Cloning, structural characterization, and chromosomal localization of the gene encoding the human prostaglandin E(2) receptor EP2 subtype.

    Science.gov (United States)

    Smock, S L; Pan, L C; Castleberry, T A; Lu, B; Mather, R J; Owen, T A

    1999-09-17

    Northern blot analysis of human placental RNA using a probe to the 5' end of the human prostaglandin E(2) (PGE(2)) EP2 receptor subtype coding region revealed the existence of a high abundance, low molecular weight transcript. To investigate the origin of this transcript, and its possible relationship to the human EP2 mRNA, we have cloned and characterized the gene encoding the human PGE(2) EP2 receptor subtype, identified transcriptional initiation and termination sites in two tissues (spleen and thymus), and determined its chromosomal localization. The human EP2 gene consists of two exons separated by a large intron, utilizes a common initiation site in both spleen and thymus at 1113 bp upstream of the translation initiation site, and has 3' transcript termini at 1140 bp and 1149 bp downstream of the translation stop site in spleen and thymus respectively. Southern and fluorescence in situ hybridization analysis demonstrated the human EP2 gene to be a single copy gene located in band 22 of the long arm of chromosome 14 (14q22). Though our initial interest in this gene was to investigate potential differential splicing of the human EP2 gene in placenta, this work demonstrates that the atypical transcript observed in placenta probably arises from a distinct, yet related, gene. Knowledge of the sequence, structure, and transcription events associated with the human EP2 gene will enable a broader understanding of its regulation and potential role in normal physiology and disease.

  12. The murine decorin. Complete cDNA cloning, genomic organization, chromosomal assignment, and expression during organogenesis and tissue differentiation.

    Science.gov (United States)

    Scholzen, T; Solursh, M; Suzuki, S; Reiter, R; Morgan, J L; Buchberg, A M; Siracusa, L D; Iozzo, R V

    1994-11-11

    Decorin, a proteoglycan known to interact with collagen and growth factors, may play key roles during ontogenesis, tissue remodeling, and cancer. We have deciphered the complete protein sequence of the murine decorin by cDNA cloning, elucidated its gene structure and chromosomal location, and investigated its expression in the developing embryo. The decorin protein and the gene were highly conserved vis à vis the human counterpart; however, the murine gene lacked a leader exon, exon Ib, which was found only in the human. Using interspecific backcrossing, we assigned the gene to chromosome 10 just proximally to the Steel gene locus. In situ hybridization studies of developing mouse embryos showed a distinct pattern of expression with a progressive increase of decorin mRNA during ontogenesis. At early stages (day 11 postconception), decorin was detectable only in the floor plate region. Subsequently (days 13-16 postconception), decorin expression was especially prominent in the meninges and mesothelial linings of pericardium, pleura, and coelomic cavity, as well as in the dermis and subepithelial layers of the intestine and urinary bladder. In contrast, the major parenchymal organs were only weakly positive for decorin mRNA. These findings suggest that decorin may play a role in epithelial/mesenchymal interactions during organ development and shaping.

  13. Rapid Emergence and Evolution of Staphylococcus aureus Clones Harboring fusC-Containing Staphylococcal Cassette Chromosome Elements.

    Science.gov (United States)

    Baines, Sarah L; Howden, Benjamin P; Heffernan, Helen; Stinear, Timothy P; Carter, Glen P; Seemann, Torsten; Kwong, Jason C; Ritchie, Stephen R; Williamson, Deborah A

    2016-04-01

    The prevalence of fusidic acid (FA) resistance amongStaphylococcus aureusstrains in New Zealand (NZ) is among the highest reported globally, with a recent study describing a resistance rate of approximately 28%. Three FA-resistantS. aureusclones (ST5 MRSA, ST1 MSSA, and ST1 MRSA) have emerged over the past decade and now predominate in NZ, and in all three clones FA resistance is mediated by thefusCgene. In particular, ST5 MRSA has rapidly become the dominant MRSA clone in NZ, although the origin of FA-resistant ST5 MRSA has not been explored, and the genetic context offusCin FA-resistant NZ isolates is unknown. To better understand the rapid emergence of FA-resistantS. aureus, we used population-based comparative genomics to characterize a collection of FA-resistant and FA-susceptible isolates from NZ. FA-resistant NZ ST5 MRSA displayed minimal genetic diversity and represented a phylogenetically distinct clade within a global population model of clonal complex 5 (CC5)S. aureus In all lineages,fusCwas invariably located within staphylococcal cassette chromosome (SCC) elements, suggesting that SCC-mediated horizontal transfer is the primary mechanism offusCdissemination. The genotypic association offusCwithmecAhas important implications for the emergence of MRSA clones in populations with high usage of fusidic acid. In addition, we found thatfusCwas colocated with a recently described virulence factor (tirS) in dominant NZS. aureusclones, suggesting a fitness advantage. This study points to the likely molecular mechanisms responsible for the successful emergence and spread of FA-resistantS. aureus.

  14. Artificially introduced aneuploid chromosomes assume a conserved position in colon cancer cells.

    Directory of Open Access Journals (Sweden)

    Kundan Sengupta

    Full Text Available BACKGROUND: Chromosomal aneuploidy is a defining feature of carcinomas. For instance, in colon cancer, an additional copy of Chromosome 7 is not only observed in early pre-malignant polyps, but is faithfully maintained throughout progression to metastasis. These copy number changes show a positive correlation with average transcript levels of resident genes. An independent line of research has also established that specific chromosomes occupy a well conserved 3D position within the interphase nucleus. METHODOLOGY/PRINCIPAL FINDINGS: We investigated whether cancer-specific aneuploid chromosomes assume a 3D-position similar to that of its endogenous homologues, which would suggest a possible correlation with transcriptional activity. Using 3D-FISH and confocal laser scanning microscopy, we show that Chromosomes 7, 18, or 19 introduced via microcell-mediated chromosome transfer into the parental diploid colon cancer cell line DLD-1 maintain their conserved position in the interphase nucleus. CONCLUSIONS: Our data is therefore consistent with the model that each chromosome has an associated zip code (possibly gene density that determines its nuclear localization. Whether the nuclear localization determines or is determined by the transcriptional activity of resident genes has yet to be ascertained.

  15. EasyClone: method for iterative chromosomal integration of multiple genes in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Jensen, Niels Bjerg; Strucko, Tomas; Kildegaard, Kanchana Rueksomtawin

    2014-01-01

    of multiple genes with an option of recycling selection markers. The vectors combine the advantage of efficient uracil excision reaction-based cloning and Cre-LoxP-mediated marker recycling system. The episomal and integrative vector sets were tested by inserting genes encoding cyan, yellow, and red...... fluorescent proteins into separate vectors and analyzing for co-expression of proteins by flow cytometry. Cells expressing genes encoding for the three fluorescent proteins from three integrations exhibited a much higher level of simultaneous expression than cells producing fluorescent proteins encoded...... on episomal plasmids, where correspondingly 95% and 6% of the cells were within a fluorescence interval of Log10 mean ± 15% for all three colors. We demonstrate that selective markers can be simultaneously removed using Cre-mediated recombination and all the integrated heterologous genes remain...

  16. Human sulfotransferase SULT1C1: cDNA cloning, tissue-specific expression, and chromosomal localization

    Energy Technology Data Exchange (ETDEWEB)

    Her, Chengtao; Weinshilboum, R.M. [Mayo Foundation, Rochester, MN (United States); Kaur, G.P. [Temple Univ. Medical School, Philadelphia, PA (United States)] [and others

    1997-05-01

    We have isolated and sequenced a cDNA that encodes an apparent human orthologue of a rat sulfotransferase (ST) cDNA that has been referred to as {open_quotes}ST1C1{close_quotes} - although it was recently recommended that sulfotransferase proteins and cDNAs be abbreviated {open_quotes}SULT.{close_quotes} The new human cDNA was cloned from a fetal liver-spleen cDNA library and had an 888-bp open reading frame. The amino acid sequence of the protein encoded by the cDNA was 62% identical with that encoded by the rat ST1C1 cDNA and included signature sequences that are conserved in all cytosolic SULT enzymes. Dot blot analysis of mRNA from 50 human tissues indicated that the cDNA was expressed in adult human stomach, kidney, and thyroid, as well as fetal kidney and liver. Northern blot analyses demonstrated that the major SULT1C1 mRNA in those same tissues was 1.4 kb in length. We next determined the partial human SULT1C1 gene sequence for a portion of the 5{prime}-terminus of one intron. That sequence was used to design SULT1C1 gene-specific primers that were used to perform the PCR with DNA from human/rodent somatic cell hybrids to demonstrate that the gene was located on chromosome 2. PCR amplifications performed with human chromosome 2/rodent hybrid cell DNA as template sublocalized SULT1C1 to a region between bands 2q11.1 and 2q11.2. 14 refs., 2 figs.

  17. cDNA cloning, chromosome mapping and expression characterization of human geranylgeranyl pyrophosphate synthase

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Geranylgeranyl pyrophosphate (GGPP) mainly participates in post-translational modification for various proteins including Rho/Rac, Rap and Rab families, as well as in regulation for cell apoptosis. Geranylgeranyl pyrophosphate synthase (GGPPS), which catalyzes the condensation reaction between farnesyl diphosphate and isopentenyl diphosphate, is the key enzyme for synthesizing GGPP. We report the isolation of a gene transcript showing high homology with Drosophila GGPPS cDNA. The transcript is 1 466 bp in length and contains an intact open reading frame (ORF) ranging from nt 239 to 1 138. This ORF encodes a deduced protein of 300 residues with calculated molecular weight of 35 ku. The deduced protein shows 57.5% identity and 75% similarity with Drosophila GGPPS, and contains five characteristic domains of prenyltransferases. Northern hybridization revealed that human GGPPS was expressed highest in heart, and moderately in spleen, testis, brain, placenta, lung, liver, skeletal muscle, kidney and pancreas. No obvious bands were detected in other examined tissues. The GGPPS gene was located on human chromosome 1q43 by Radiation Hybrid mapping method. It was proved that there was a putative predisposing gene for prostate cancer in this region, and that analogs of GGPP can inhibit the geranylgeranylation of p21rap protein in PC-3 prostate cancer cell lines. These facts suggest that GGPPS may be one of the candidate genes for prostate cancer.

  18. Seamless Ligation Cloning Extract (SLiCE) cloning method.

    Science.gov (United States)

    Zhang, Yongwei; Werling, Uwe; Edelmann, Winfried

    2014-01-01

    SLiCE (Seamless Ligation Cloning Extract) is a novel cloning method that utilizes easy to generate bacterial cell extracts to assemble multiple DNA fragments into recombinant DNA molecules in a single in vitro recombination reaction. SLiCE overcomes the sequence limitations of traditional cloning methods, facilitates seamless cloning by recombining short end homologies (15-52 bp) with or without flanking heterologous sequences and provides an effective strategy for directional subcloning of DNA fragments from bacterial artificial chromosomes or other sources. SLiCE is highly cost-effective and demonstrates the versatility as a number of standard laboratory bacterial strains can serve as sources for SLiCE extract. We established a DH10B-derived E. coli strain expressing an optimized λ prophage Red recombination system, termed PPY, which facilitates SLiCE with very high efficiencies.

  19. An A-T linker adapter polymerase chain reaction method for chromosome walking without restriction site cloning bias.

    Science.gov (United States)

    Trinh, Quoclinh; Xu, Wentao; Shi, Hui; Luo, Yunbo; Huang, Kunlun

    2012-06-01

    A-T linker adapter polymerase chain reaction (PCR) was modified and employed for the isolation of genomic fragments adjacent to a known DNA sequence. The improvements in the method focus on two points. The first is the modification of the PO(4) and NH(2) groups in the adapter to inhibit the self-ligation of the adapter or the generation of nonspecific products. The second improvement is the use of the capacity of rTaq DNA polymerase to add an adenosine overhang at the 3' ends of digested DNA to suppress self-ligation in the digested DNA and simultaneously resolve restriction site clone bias. The combination of modifications in the adapter and in the digested DNA leads to T/A-specific ligation, which enhances the flexibility of this method and makes it feasible to use many different restriction enzymes with a single adapter. This novel A-T linker adapter PCR overcomes the inherent limitations of the original ligation-mediated PCR method such as low specificity and a lack of restriction enzyme choice. Moreover, this method also offers higher amplification efficiency, greater flexibility, and easier manipulation compared with other PCR methods for chromosome walking. Experimental results from 143 Arabidopsis mutants illustrate that this method is reliable and efficient in high-throughput experiments.

  20. Bacterial artificial chromosomes (BACs)-on-Beads™ as a diagnostic platform for the rapid aneuploidy screening of products of conception.

    Science.gov (United States)

    Sheath, Karen L; Duffy, Lisa; Asquith, Philip; Love, Donald R; George, Alice M

    2013-08-01

    The aim of the present study was to evaluate the use of KaryoLite™ bacterial artificial chromosomes (BACs)‑on‑Beads™ (BoBs) technology for the rapid screening of products of conception (POC). Validation and prospective studies were carried out on 85 and 95 patient samples, respectively. Validation studies had previously been analyzed using routine culture and G-banded karyotyping. BoBs resulted in an abnormality detection frequency of 27%, with a failure rate of <3%. The time required for processing was significantly lower compared with that of tissue culture. In conclusion, BoBs technology decreased the failure rate, while increasing the analytical sensitivity compared with G-banded karyotype analysis alone. Additionally, significant cost savings may be achieved with regard to the time of processing and analysis of specimens.

  1. Construction of a bacterial artificial chromosome library of S-type CMS maize mitochondria

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to isolate mitochondrial genes easily, we have developed a new method to construct S-type CMS maize mitochondrial gene library by means of embedding mitochondria and enzymatic digesting mitochondria in situ, preparing mtDNA by electrophoresis, digesting LMP agarose with β-agarase, using BAC vector and electroporation. About 2 500 white clones of Mo17 CMS-J mitochondrial gene library were obtained with the average size of 18.24 kb, ranging from 5 to 40 kb, 63.6% inserts came from mitochondrial genome and represented 48 ′ mitochondrial genome equivalents. All the probes had detected the positive clones in the gene library. It is helpful to elucidating the maize mitochondrial genome structure and mechanism of S-type CMS, and may give some valuable reference to the construction of other plant mitochondrial genome library.

  2. Isolation and characterization of DNA probes for human chromosome 21.

    Science.gov (United States)

    Watkins, P C

    1990-01-01

    A coordinated effort to map and sequence the human genome has recently become a national priority. Chromosome 21, the smallest human chromosome accounting for less than 2% of the human genome, is an attractive model system for developing and evaluating genome mapping technology. Several strategies are currently being explored including the development of chromosome 21 libraries from somatic cell hybrids as reported here, the cloning of chromosome 21 in yeast artificial chromosomes (McCormick et al., 1989b), and the construction of chromosome 21 libraries using chromosome flow-sorting techniques (Fuscoe et al., 1989). This report describes the approaches used to identify DNA probes that are useful for mapping chromosome 21. Probes were successfully isolated from both phage and cosmid libraries made from two somatic cell hybrids that contain human chromosome 21 as the only human chromosome. The 15 cosmid clones from the WA17 library, reduced to cloned DNA sequences of an average size of 3 kb, total 525 kb of DNA which is approximately 1% of chromosome 21. From these clones, a set of polymorphic DNA markers that span the length of the long arm of chromosome 21 has been generated. All of the probes thus far analyzed from the WA17 libraries have been mapped to chromosome 21 both by physical and genetic mapping methods. It is therefore likely that the WA17 hybrid cell line contains human chromosome 21 as the only human component, in agreement with cytogenetic observation. The 153E7b cosmid libraries will provide an alternative source of cloned chromosome 21 DNA. Library screening techniques can be employed to obtain cloned DNA sequences from the same genetic loci of the two different chromosome 21s. Comparative analysis will allow direct estimation of DNA sequence variation for different regions of chromosome 21. Mapped DNA probes make possible the molecular analysis of chromosome 21 at a level of resolution not achievable by classical cytogenetic techniques (Graw et al

  3. Construction of a full bacterial artificial chromosome (BAC) library of Oryza sativa genome

    Institute of Scientific and Technical Information of China (English)

    TAOQUANZHOU; HAIYINGZHAO; 等

    1994-01-01

    We have constructed a full BAC library for the superior early indica variety of Oryza sativa,Guang Lu Ai 4.The MAX Efficiency DH10B with increased stability of inserts was used as BAC host cells.The potent pBelo BACII with double selection markers was used as cloning vector.The cloning efficiency we have reached was as high as 98%,and the transformation efficiency was raised up to 106 transformants/μg of large fragment DNA.The BAC recombinant transformants were picked at random and analyzed for the size of inserts,which turned out to be of 120 kb in length on average.We have obtained more than 20,000 such BAC clones.According to conventional probability equation,they covered the entire rice genome of 420,000 kb in length.The entire length of inserts of the library obtained has the 5-to 6-fold coverage of the genome.To our knowledge,this is the first reported full BAC library for a complex genome.

  4. The construction of a yeast artificial chromosome (YAC) contig in the vicinity of the Usher syndrome type IIa (USH2A) gene in 1q41

    Energy Technology Data Exchange (ETDEWEB)

    Sumegi, Janos; Wang, Ji-Yi; Zhen, Dong-Kai [Univ. of Nebraska Medical Center, Omaha, NE (United States)] [and others

    1996-07-01

    The gene for Usher syndrome type II (USH2A), and autosomal recessive syndromic deafness, has been mapped to a region of 1q41 flanked proximally by D1S217 and distally by D1S439. Using sequence-tagged sites (STSs) within the region, a total of 21 yeast artificial chromosome (YAC) clones were isolated and ordered into a single contig that spans approximately 11.0 Mb. The order of microsatellite and STS markers in this region was established as D1S505-D1S425-DXS217-D1S556-D1S237-D1S474-EB1-KB6-AFM144XF2-KB1-KB4-D1S229-D1S490-D1S227-TGF{beta}2-D1S439. Analysis of newly positioned polymorphic markers in recombinant individuals in two Usher syndrome type IIa families has enabled us to identify DXS474 and AFM144XF2 as two flanking markers for the Usher type IIa locus. The physical distance between the two markers is 1.0 Mb. This region is covered by eight YACs from the CEPH library: 945f7, 867g9, 762a6, 919h3, 794b8, 785h4, 848b9, and 841g2. A long range physical map of the Usher type IIa critical region, using MluI, BssHII, NotI, EagI, and SacII, has been developed. 41 refs., 5 figs.

  5. Cloning of the cDNA for a human homologue of the Drosophila white gene and mapping to chromosome 21q22.3

    Energy Technology Data Exchange (ETDEWEB)

    Haiming Chen; Lalioti, M.D.; Perrin, G.; Antonarakis, S.E. [Univ. of Geneva Medical School (Switzerland)] [and others

    1996-07-01

    In an effort to contribute to the transcript map of human chromosome 21 and the understanding of the pathophysiology of trisomy 21, we have used exon trapping to identify fragments of chromosome 21 genes. Two trapped exons, from pools of chromosome 21-specific cosmids, showed homology to the Drosophila white (w) gene. We subsequently cloned the corresponding cDNA for a human homologue of the Drosophila w gene (hW) from human retina and fetal brain cDNA libraries. The gene belongs to the ATP-binding cassette transporter gene family and is homologous to Drosophila w (and to 2 genes from other species) and to a lesser extent to Drosophila brown (bw) and scarlet (st) genes that are all involved in the transport of eye pigment precursor molecules. A DNA polymorphism with 62% heterozygosity due to variation of a poly (T) region in the 3{prime} UTR of the hW has been identified and used for the incorporation of this gene to the genetic map of chromosome 21. The hW is located at 21q22.3 between DNA markers D21S212 and D21S49 in a P1 clone that also contains marker BCEI. The gene is expressed at various levels in many human tissues. The contributions of this gene to the Down syndrome phenotypes, to human eye color, and to the resulting phenotypes of null or missense mutations are presently unknown. 56 refs., 8 figs., 1 tab.

  6. Correction of chromosomal instability and sensitivity to diverse mutagens by a cloned cDNA of the XRCC3 DNA repair gene

    Energy Technology Data Exchange (ETDEWEB)

    Tebbs, R.S.; Tucker, J.D.; Hwang, M. [Lawrence Livermore National Lab., CA (United States)] [and others

    1995-07-03

    The mutagen-sensitive CHO line irs1SF was previously isolated on the basis of hypersensitivity to ionizing radiation and was found to be chromosomally unstable as well as cross-sensitive to diverse kinds of DNA-damaging agents. The analysis of somatic cell hybrids formed between irs1SF and human lymphocytes implicated a human gene (defined as XRCC3; x-ray repair cross-complementing), which partially restored mitomycin C resistance to the mutant. A functional cDNA that confers mitomycin C resistance was transferred to irs1SF cells by transforming them with an expression cDNA library and obtaining primary and secondary transformants. Functional cDNA clones were recovered from a cosmid library prepared from a secondary transformant. Transformants also showed partial correction of sensitivity to displatin and {gamma}-rays, efficient correction of chromosomal instability, and substantially improved plating efficiency and growth rate. The XRCC3 cDNA insert is {approx} 2.5 kb and detects an {approx} 3.0-kb mRNA on Northern blots. The cDNA was mapped by fluorescence in situ hybridization to human chromosome 14q32.3, which was consistent with the chromosome concordance data of two independent hybrid clone panels. 30 refs., 5 figs., 2 tabs.

  7. Cloning, tissue expression pattern characterization and chromosome localization of human peptide methionine sulfoxide reductase cDNA

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Oxidation and reduction of some amino acids are one of the molecular mechanisms for regulating the function of proteins. The oxidation of methionine (Met) to methionine sulfoxide (Met(O)) results in decreasing or loss of the biological activity of related proteins. It was found that peptide methionine sulfoxide reductase (msrA) can reduce Met(O) to Met and therefore restored the biological function of the oxidized proteins. To reveal the methionine oxidation-reduction mechanism in human body, in this study, the cDNA sequence of bovine msrA was used as an information-probe to screen the human EST database. Based on a contig assembled from homologous ESTs, a 1 256-bp human MSRA cDNA was cloned from several human cDNA libraries. The cDNA contains an open reading frame (ORF) of 705 bp in length, which encodes 235 amino acid residues. Homology comparison revealed that human MSRA shares 88% and 61% identities with bovine and Escherichia coli msrA protein respectively. Expression pattern analysis revealed a single 1.6-kb transcript of human MSRA in most human tissues and with highest expression in kidney. By radiation hybrid panel mapping, the gene was localized to human chromosome 8p22-23 between markers D8S518 and D8S550. There are 2 human inherited diseases Keratolytic Winter Erythema and Microcephaly related genes in this region, it is inferred that human MSRA might be the candidate of the two diseases.

  8. Viral Bacterial Artificial Chromosomes: Generation, Mutagenesis, and Removal of Mini-F Sequences

    Directory of Open Access Journals (Sweden)

    B. Karsten Tischer

    2012-01-01

    Full Text Available Maintenance and manipulation of large DNA and RNA virus genomes had presented an obstacle for virological research. BAC vectors provided a solution to both problems as they can harbor large DNA sequences and can efficiently be modified using well-established mutagenesis techniques in Escherichia coli. Numerous DNA virus genomes of herpesvirus and pox virus were cloned into mini-F vectors. In addition, several reverse genetic systems for RNA viruses such as members of Coronaviridae and Flaviviridae could be established based on BAC constructs. Transfection into susceptible eukaryotic cells of virus DNA cloned as a BAC allows reconstitution of recombinant viruses. In this paper, we provide an overview on the strategies that can be used for the generation of virus BAC vectors and also on systems that are currently available for various virus species. Furthermore, we address common mutagenesis techniques that allow modification of BACs from single-nucleotide substitutions to deletion of viral genes or insertion of foreign sequences. Finally, we review the reconstitution of viruses from BAC vectors and the removal of the bacterial sequences from the virus genome during this process.

  9. Construction of BAC Libraries from Flow-Sorted Chromosomes.

    Science.gov (United States)

    Šafář, Jan; Šimková, Hana; Doležel, Jaroslav

    2016-01-01

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

  10. ADVANCES IN REPRODUCTIVE TECHNOLOGIES IN CATTLE: FROM ARTIFICIAL INSEMINATION TO CLONING

    Directory of Open Access Journals (Sweden)

    M Bertolini

    2009-01-01

    Full Text Available El afán por controlar los procesos reproductivos en animales ha llevado a una gran ganancia en conocimiento, impulsando el desarrollo de cuatro tecnologías reproductivas asistidas (ARTS para animales y humanos. El uso de ARTS ha sido de gran importancia en la producción ganadera. En términos generales, las tres principales generaciones de ART, incluyendo 1 inseminación artificial (AI y congelación de gametos y embriones, 2 superovulación y transferencia de embriones (MOET y 3 procedimientos de fertilización in Vitro, han madurado en aplicaciones comerciales exitosas, facilitando el incremento en la producción a través de la genética, reducción del intervalo generacional, control de enfermedades, y reducción de costos de producción. La cuarta generación de ARTS incluye procesos que aún son muy experimentales, como transferencia de núcleos (NT de células somáticas, transgénesis, y biología de células madre. Estas tecnologías se intercalan las unas con las otras y con las herramientas moleculares actuales, dependen completamente de las generaciones de tecnologías previas. Sin embargo, hay muchos retos reproductivos que no permiten alcanzar el potencial reproductivo máximo, afectando la productividad y la rentabilidad. Es claro que la aplicación de tales tecnologías como actividades lucrativas se mantendrán cuestionadas si no se asocian a otros componentes de la producción pecuaria, como la salud animal, nutrición, y prácticas de manejo adecuadas.

  11. cDNA cloning and chromosomal mapping of a predicted coiled-coil proline-rich protein immunogenic in meningioma patients.

    Science.gov (United States)

    Heckel, D; Brass, N; Fischer, U; Blin, N; Steudel, I; Türeci, O; Fackler, O; Zang, K D; Meese, E

    1997-11-01

    There is increasing evidence that tumor expressed genes induce immune responses in cancer patients. To identify meningioma expressed antigens, we established a meningioma expression library which was screened with autologous serum. Out of 20 positive cDNA clones eight share high sequence homologies as determined by sequence analysis. These eight clones can be grouped into three classes which differ in length and which are characterized by specific sequence variations. The longest open reading frame was found to be 2412 bp encoding an immunoreactive antigen termed meningioma expressed antigen 6 (MEA6). Using five sequence specific primer pairs, somatic hybrid panel mapping revealed locations of the three classes on several human chromosomes including chromosomes 2, 3, 6, 7, 9, 13 and 14. The mapping results were confirmed by fluorescence in situ hybridization. RT-PCR showed consistent expression of all classes in several meningiomas and additional tissues using the same set of primer pairs as for chromosomal mapping. The expression data were confirmed by northern blot analysis. For the predicted amino acid sequence BLASTX revealed a homology to a human C219-reactive peptide which was previously isolated by an antibody directed against p-glycoprotein. Sequence properties of the MEA protein include an acidic activation domain, a proline-rich region and two coiled-coil domains indicating protein binding and activation functions.

  12. Cloning of cDNA and genomic DNA encoding human type XVIII collagen and localization of the [alpha]1 (XVIII) collagen gene to mouse chromosome 10 and human chromosome 21

    Energy Technology Data Exchange (ETDEWEB)

    Oh, S.P.; Warman, M.L.; Timmons, S.; Olsen, B.R.; Knoll, J.H.M. (Harvard Medical School, Boston, MA (United States)); Seldin, M.F. (Duke Univ. Medical Center, Durham, NC (United States)); Cheng, Sou-De (Children' s Hospital/Harvard Medical School, Boston, MA (United States))

    1994-02-01

    Types XV and XVIII collagen belong to a unique and novel subclass of the collagen superfamily for which the authors have proposed the name the MULTIPLEXIN family. Members of this class contain polypeptides with multiple triple-helical domains separated and flanked by non-triple-helical regions. In this paper, they report the isolation of human cDNAs and genomic DNAs encoding the [alpha]1 (XVIII) collagen chain. Utilizing a genomic clone as probe, they have mapped the COL18A1 gene to chromosome 21q22.3 by fluorescence in situ hybridization. In addition, using an interspecific backcross panel, they have shown that the murine Col18a1 locus is on chromosome 10, close to the loci for Col6a1 and Col6a2. 16 refs., 5 figs.

  13. [Distribution of abnormal cell clone with deletion of chromosome 20q in marrow cell lineages and apoptosis cells in myelodysplastic syndrome].

    Science.gov (United States)

    Qin, Ling; Wang, Chun; Qin, You-Wen; Xie, Kuang-Cheng; Yan, Shi-Ke; Gao, Yan-Rong; Wang, Xiao-Rui; Zhao, Chu-Xian

    2008-06-01

    This study was aimed to investigate the distribution of abnormal clone in marrow cell lineages and apoptosis cells in myelodysplastic syndrome (MDS) with deletion of chromosome 20q. Monoclonal antibodies recognizing myeloid precursors (CD15), erythroid precursors (GPA), T cells (CD3(+)CD56(-)CD16(-)), B cells (CD19), NK cells (CD3(-)CD56(+)CD16(+)) were used to sort bone marrow cells in a MDS patient with del (20q) by fluorescence activated cell sorting (FACS). Annexin V-FITC and PI were used to sort bone marrow Annexin V(+)PI(-) and Annexin V(-)PI(-) cells by FACS. The sorted positive cells were detected by interphase dual-color fluorescence in situ hybridization (D-FISH) using a LSI D20S108 probe (Spectrum Orange) and a Telvysion TM 20p probe (Spectrum Green). FACS and FISH analysis were also performed on the samples from 4 cases with normal karyotype. The results showed that the proportions of MDS clone in the myeloid and erythroid precursors were 70.50% and 93.33% respectively, in the RAEB-1 patient with del (20q) and were obviously higher than that in control group (5.39% and 6.17%). The proportions of abnormal clone in T, B and NK cells were 3.23%, 4.32% and 5.77% respectively and were less than that in control group (5.76%, 4.85%, 6.36%). The percentage of apoptotic cells in the bone marrow nucleated cells was 16.09%. The proportions of MDS clone in Annexin V(+)PI(-) and Annexin V(-)PI(-) cells were 32.48% and 70.11%, respectively. It is concluded that most myeloid and erythroid precursors are originated from the abnormal clone in MDS with del (20q). A little part of apoptotic cells are derived from the abnormal clone.

  14. Incorporation of a lambda phage recombination system and EGFP detection to simplify mutagenesis of Herpes simplex virus bacterial artificial chromosomes

    Directory of Open Access Journals (Sweden)

    Weir Jerry P

    2007-05-01

    Full Text Available Abstract Background Targeted mutagenesis of the herpesvirus genomes has been facilitated by the use of bacterial artificial chromosome (BAC technology. Such modified genomes have potential uses in understanding viral pathogenesis, gene identification and characterization, and the development of new viral vectors and vaccines. We have previously described the construction of a herpes simplex virus 2 (HSV-2 BAC and the use of an allele replacement strategy to construct HSV-2 recombinants. While the BAC mutagenesis procedure is a powerful method to generate HSV-2 recombinants, particularly in the absence of selective marker in eukaryotic culture, the mutagenesis procedure is still difficult and cumbersome. Results Here we describe the incorporation of a phage lambda recombination system into an allele replacement vector. This strategy enables any DNA fragment containing the phage attL recombination sites to be efficiently inserted into the attR sites of the allele replacement vector using phage lambda clonase. We also describe how the incorporation of EGFP into the allele replacement vector can facilitate the selection of the desired cross-over recombinant BACs when the allele replacement reaction is a viral gene deletion. Finally, we incorporate the lambda phage recombination sites directly into an HSV-2 BAC vector for direct recombination of gene cassettes using the phage lambda clonase-driven recombination reaction. Conclusion Together, these improvements to the techniques of HSV BAC mutagenesis will facilitate the construction of recombinant herpes simplex viruses and viral vectors.

  15. Process for assembly and transformation into Saccharomyces cerevisiae of a synthetic yeast artificial chromosome containing a multigene cassette to express enzymes that enhance xylose utilization designed for an automated pla

    Science.gov (United States)

    A yeast artificial chromosome (YAC) containing a multigene cassette for expression of enzymes that enhance xylose utilization (xylose isomerase [XI] and xylulokinase [XKS]) was constructed and transformed into Saccharomyces cerevisiae to demonstrate feasibility as a stable protein expression system ...

  16. Development of one set of chromosome-specific microsatellite-containing BACs and their physical mapping in Gossypium hirsutum L.

    Science.gov (United States)

    Wang, Kai; Guo, Wangzhen; Zhang, Tianzhen

    2007-09-01

    Fluorescence in situ hybridization (FISH), using bacterial artificial chromosome (BAC) clone as probe, is a reliable cytological technique for chromosome identification. It has been used in many plants, especially in those containing numerous small chromosomes. We previously developed eight chromosome-specific BAC clones from tetraploid cotton, which were used as excellent cytological markers for chromosomes identification. Here, we isolated the other chromosome-specific BAC clones to make a complete set for the identification of all 26 chromosome-pairs by this technology in tetraploid cotton (Gossypium hirsutum L.). This set of BAC markers was demonstrated to be useful to assign each chromosome to a genetic linkage group unambiguously. In addition, these BAC clones also served as convenient and reliable landmarks for establishing physical linkage with unknown targeted sequences. Moreover, one BAC containing an EST, with high sequence similarity to a G. hirsutum ethylene-responsive element-binding factor was located physically on the long arm of chromosome A7 with the help of a chromosome-A7-specific BAC FISH marker. Comparative analysis of physical marker positions in the chromosomes by BAC-FISH and genetic linkage maps demonstrated that most of the 26 BAC clones were localized close to or at the ends of their respective chromosomes, and indicated that the recombination active regions of cotton chromosomes are primarily located in the distal regions. This technology also enables us to make associations between chromosomes and their genetic linkage groups and re-assign each chromosome according to the corresponding genetic linkage group. This BAC clones and BAC-FISH technology will be useful for us to evaluate grossly the degree to which a linkage map provides adequate coverage for developing a saturated genetic map, and provides a powerful resource for cotton genomic researches.

  17. Cloning of a parathyroid hormone/parathyroid hormone-related peptide receptor (PTHR) cDNA from a rat osteosarcoma (UMR 106) cell line: Chromosomal assignment of the gene in the human, mouse, and rat genomes

    Energy Technology Data Exchange (ETDEWEB)

    Pausova, Z.; Bourdon, J.; Clayton, D.; Janicic, N.; Goltzman, D.; Hendy, G.N. (McGill Univ. and Royal Victoria Hospital, Montreal Quebec (Canada)); Mattei, M.G. (INSERM, Marseille (France)); Seldin, M.F. (Duke Univ. Medical Center, Durham, NC (United States)); Riviere, M.; Szpirer, J. (Universite Libre de Bruxelles, Rhode-St-Genese (Belgium)) (and others)

    1994-03-01

    Complementary DNAs spanning the entire coding region of the rat parathyroid hormone/parathyroid hormone-related peptide receptor (PTHR) were isolated from a rat osteosarcoma (UMR 106) cell-line cDNA library. The longest of these clones (rPTHrec4) was used to chromosomally assign the PTHR gene in the human, rat, and mouse genomes. By somatic cell hybrid analysis, the gene was localized to human chromosome 3 and rat chromosome 8; by in situ hybridization, the gene was mapped to human chromosome 3p21.1-p22 and to mouse chromosome 9 band F; and by interspecific backcross analysis, the Pthr gene segregated with the transferrin (Trf) gene in chromosome 9 band F. Mouse chromosome 9 and rat chromosome 8 are known to be highly homologous and to also show synteny conservation with human chromosome 3. These three chromosomes share the transferrin gene (TF), the myosin light polypeptide 3 gene (MYL3), and the acelpeptide hydrolase gene (APEH). These results add a fourth gene, the PTHR gene, to the synteny group conserved in these chromosomes. 34 refs., 7 figs. 1 tab.

  18. A method for producing transgenic cells using a multi-integrase system on a human artificial chromosome vector.

    Directory of Open Access Journals (Sweden)

    Shigeyuki Yamaguchi

    Full Text Available The production of cells capable of expressing gene(s of interest is important for a variety of applications in biomedicine and biotechnology, including gene therapy and animal transgenesis. The ability to insert transgenes at a precise location in the genome, using site-specific recombinases such as Cre, FLP, and ΦC31, has major benefits for the efficiency of transgenesis. Recent work on integrases from ΦC31, R4, TP901-1 and Bxb1 phages demonstrated that these recombinases catalyze site-specific recombination in mammalian cells. In the present study, we examined the activities of integrases on site-specific recombination and gene expression in mammalian cells. We designed a human artificial chromosome (HAC vector containing five recombination sites (ΦC31 attP, R4 attP, TP901-1 attP, Bxb1 attP and FRT; multi-integrase HAC vector and de novo mammalian codon-optimized integrases. The multi-integrase HAC vector has several functions, including gene integration in a precise locus and avoiding genomic position effects; therefore, it was used as a platform to investigate integrase activities. Integrases carried out site-specific recombination at frequencies ranging from 39.3-96.8%. Additionally, we observed homogenous gene expression in 77.3-87.5% of colonies obtained using the multi-integrase HAC vector. This vector is also transferable to another cell line, and is capable of accepting genes of interest in this environment. These data suggest that integrases have high DNA recombination efficiencies in mammalian cells. The multi-integrase HAC vector enables us to produce transgene-expressing cells efficiently and create platform cell lines for gene expression.

  19. Uroporphyrinogen-III synthase: Molecular cloning, nucleotide sequence, expression of a mouse full-length cDNA, and its localization on mouse chromosome 7

    Energy Technology Data Exchange (ETDEWEB)

    Xu, W.; Desnick, R.J. [Mount Sinai School of Medicine, New York, NY (United States); Kozak, C.A. [National Institute of Health, Bethesda, MD (United States)

    1995-04-10

    Uroporphyrinogen-III synthase, the fourth enzyme in the heme biosynthetic pathway, is responsible for the conversion of hydroxymethylbilane to the cyclic tetrapyrrole, uroporphyrinogen III. The deficient activity of URO-S is the enzymatic defect in congenital erythropoietic porphyria (CEP), an autosomal recessive disorder. For the generation of a mouse model of CEP, the human URO-S cDNA was used to screen 2 X 10{sup 6} recombinants from a mouse adult liver cDNA library. Ten positive clones were isolated, and dideoxy sequencing of the entire 1.6-kb insert of clone pmUROS-1 revealed 5{prime} and 3{prime} untranslated sequences of 144 and 623 bp, respectively, and an open reading frame of 798 bp encoding a 265-amino-acid polypeptide with a predicted molecular mass of 28,501 Da. The mouse and human coding sequences had 80.5 and 77.8% nucleotide and amino acid identity, respectively. The authenticity of the mouse cDNA was established by expression of the active monomeric enzyme in Escherichia coli. In addition, the analysis of two multilocus genetic crosses localized the mouse gene on chromosome 7, consistent with the mapping of the human gene to a position of conserved synteny on chromosome 10. The isolation, expression, and chromosomal mapping of this full-length cDNA should facilitate studies of the structure and organization of the mouse genomic sequence and the development of a mouse model of CEP for characterization of the disease pathogenesis and evaluation of gene therapy. 38 refs., 1 tab.

  20. Analysis of chromosome conservation in Lemur catta studied by chromosome paints and BAC/PAC probes.

    Science.gov (United States)

    Cardone, Maria Francesca; Ventura, Mario; Tempesta, Sergio; Rocchi, Mariano; Archidiacono, Nicoletta

    2002-12-01

    A panel of human chromosome painting probes and bacterial and P1 artificial chromosome (BAC/PAC) clones were used in fluorescence in situ hybridization (FISH) experiments to investigate the chromosome conservation of the ring-tailed lemur (Lemur catta, LCA) with respect to human. Whole chromosome paints specific for human chromosomes 7, 9, 11, 13, 14, 17, 18, 20, 21, and X were found to identify a single chromosome or an uninterrupted chromosomal region in LCA. A large set of partial chromosome paints and BAC/PAC probes were then used to refine the characterization of the rearrangements differentiating the two karyotypes. The results were also used to reconstruct the ancestral Lemuridae karyotype. Lemur catta, indeed, can be used as an outgroup, allowing symplesiomorphic (ancestral) rearrangements to be distinguished from apomorphic (derived) rearrangements in lemurs. Some LCA chromosomes are difficult to distinguish morphologically. The 'anchorage' of most LCA chromosomes to specific probes will contribute to the standardization of the karyotype of this species.

  1. Protective efficacy of a recombinant BAC clone of Marek's disease virus containing REV-LTR

    Science.gov (United States)

    Insertion of reticuloendotheliosis virus (REV) long-terminal repeat (LTR) into a bacterial artificial chromosome (BAC) clone of a very virulent strain of Marek’s disease (MD) virus (MDV), Md5 (Kim et al, 2011) rendered the resultant recombinant virus termed rMd5 REV-LTR BAC fully attenuated at passa...

  2. Fluorescent in-situ hybridization of cattle and sheep chromosomes with cloned human fragile-X DNA

    DEFF Research Database (Denmark)

    Ali, Ahmd; Thomsen, Preben Dybdahl; Babar, M.E.

    2009-01-01

    An extensive study on spontaneous and 5-Fluorodeoxyuridine induced fragile sites identified Xq31 in cattle (Bos taurus) and (Xq24, Xq26) in sheep (Ovis aries) in addition to several autosomal fragile sites (under publication). A ZOO-FISH study using three cloned human fragile-X probes with CCG/CG...

  3. [Developing a physical map of human chromosome 22]. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Simon, M.I.

    1991-12-31

    We have developed bacterial F-factor based systems for cloning large fragments of human DNA in E. coli. In addition to large size, these systems are capable of maintaining human DNA with a high degree of stability. The cosmid size clones are called Fosmids and the clones containing larger inserts (100--200 kb) are called bacterial artificial chromosomes (BACs). The ultimate test of the effectiveness of cloning and mapping technology is the degree to which it can be efficiently applied to solve complex mapping problems. We, therefore, plan to use the large fragment cloning procedure as well as a variety of other approaches to generate a complete map of overlapping clones corresponding to human chromosome 22. We have thus far prepared two human chromosome 22 specific Fosmid libraries and we are in the process of constructing a chromosome 22 specific BAC library composed of fragments larger than 100 kb. We will further optimize the technology so that libraries of fragments larger than 200 kb can be readily prepared.

  4. (Developing a physical map of human chromosome 22)

    Energy Technology Data Exchange (ETDEWEB)

    Simon, M.I.

    1991-01-01

    We have developed bacterial F-factor based systems for cloning large fragments of human DNA in E. coli. In addition to large size, these systems are capable of maintaining human DNA with a high degree of stability. The cosmid size clones are called Fosmids and the clones containing larger inserts (100--200 kb) are called bacterial artificial chromosomes (BACs). The ultimate test of the effectiveness of cloning and mapping technology is the degree to which it can be efficiently applied to solve complex mapping problems. We, therefore, plan to use the large fragment cloning procedure as well as a variety of other approaches to generate a complete map of overlapping clones corresponding to human chromosome 22. We have thus far prepared two human chromosome 22 specific Fosmid libraries and we are in the process of constructing a chromosome 22 specific BAC library composed of fragments larger than 100 kb. We will further optimize the technology so that libraries of fragments larger than 200 kb can be readily prepared.

  5. Some observations on the pathogenicity of a molecular clone of a very virulent strain of Marek’s disease virus containing an insert of long terminal repeat of reticuloendotheliosis virus

    Science.gov (United States)

    We recently artificially inserted REV LTR into a bacterial artificial chromosome (BAC) clone of a very virulent strain of Marek’s disease (MD) virus (MDV), Md5; the virus was designated rMd5-RM1-LTR (Kim et al., 2011). In the present study, susceptible chickens of ADOL line 15I5 X 71 with and witho...

  6. Cloning and characterization of a novel gene (C17orf25) from the deletion region on chromosome 17p13.3 in hepatocelular carcinoma

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open reading frame 25, previously named it HC71A), from the deletion region on chromosome 17p13.3. The cDNA encodes a protein of 313 amino acids with a calculated molecular mass of 34.8 kDa. C17orf25 is divided into 10 exons and 9 introns, spanning 23 kb of genomic DNA. Northern blot analysis showed that the mRNA expression of C17orf25 was decreased in hepatocellular carcinoma samples as compared to adjacent noncancerous liver tissues from the same patients. The transfection of C17orf25 into the hepatocellular carcinoma cell SMMC7721 and overexpression could inhibit the cell growth. The above results indicate that C17orf25 is a novel human gene, and the cloning and preliminary characterization of C17orf25 is a prerequisite for further functional analysis of this novel gene in human hepatocellular carcinoma.

  7. Fusion primer and nested integrated PCR (FPNI-PCR: a new high-efficiency strategy for rapid chromosome walking or flanking sequence cloning

    Directory of Open Access Journals (Sweden)

    Wang Zhen

    2011-11-01

    Full Text Available Abstract Background The advent of genomics-based technologies has revolutionized many fields of biological enquiry. However, chromosome walking or flanking sequence cloning is still a necessary and important procedure to determining gene structure. Such methods are used to identify T-DNA insertion sites and so are especially relevant for organisms where large T-DNA insertion libraries have been created, such as rice and Arabidopsis. The currently available methods for flanking sequence cloning, including the popular TAIL-PCR technique, are relatively laborious and slow. Results Here, we report a simple and effective fusion primer and nested integrated PCR method (FPNI-PCR for the identification and cloning of unknown genomic regions flanked known sequences. In brief, a set of universal primers was designed that consisted of various 15-16 base arbitrary degenerate oligonucleotides. These arbitrary degenerate primers were fused to the 3' end of an adaptor oligonucleotide which provided a known sequence without degenerate nucleotides, thereby forming the fusion primers (FPs. These fusion primers are employed in the first step of an integrated nested PCR strategy which defines the overall FPNI-PCR protocol. In order to demonstrate the efficacy of this novel strategy, we have successfully used it to isolate multiple genomic sequences namely, 21 orthologs of genes in various species of Rosaceace, 4 MYB genes of Rosa rugosa, 3 promoters of transcription factors of Petunia hybrida, and 4 flanking sequences of T-DNA insertion sites in transgenic tobacco lines and 6 specific genes from sequenced genome of rice and Arabidopsis. Conclusions The successful amplification of target products through FPNI-PCR verified that this novel strategy is an effective, low cost and simple procedure. Furthermore, FPNI-PCR represents a more sensitive, rapid and accurate technique than the established TAIL-PCR and hiTAIL-PCR procedures.

  8. Development of stable reporter system cloning luxCDABE genes into chromosome of Salmonella enterica serotypes using Tn7 transposon

    Directory of Open Access Journals (Sweden)

    Lawrence Mark L

    2010-07-01

    Full Text Available Abstract Background Salmonellosis may be a food safety problem when raw food products are mishandled and not fully cooked. In previous work, we developed bioluminescent Salmonella enterica serotypes using a plasmid-based reporting system that can be used for real-time monitoring of the pathogen's growth on food products in short term studies. In this study, we report the use of a Tn7-based transposon system for subcloning of luxCDABE genes into the chromosome of eleven Salmonella enterica serotypes isolated from the broiler production continuum. Results We found that the lux operon is constitutively expressed from the chromosome post-transposition and the lux cassette is stable without external pressure, i.e. antibiotic selection, for all Salmonella enterica serotypes used. Bioluminescence expression is based on an active electron transport chain and is directly related with metabolic activity. This relationship was quantified by measuring bioluminescence against a temperature gradient in aqueous solution using a luminometer. In addition, bioluminescent monitoring of two serotypes confirmed that our chicken skin model has the potential to be used to evaluate pathogen mitigation strategies. Conclusions This study demonstrated that our new stable reporting system eliminates bioluminescence variation due to plasmid instability and provides a reliable real-time experimental system to study application of preventive measures for Salmonella on food products in real-time for both short and long term studies.

  9. Cloning of the VASP (Vasodilator-Stimulated Phosphoprotein) genes in human and mouse: Structure, sequence, and chromosomal localization

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, M.; Fischer, L.; Hauser, W. [Medizinische Universitaetsklinik, Wuerzburg (Germany)] [and others

    1996-09-01

    The genes encoding the vasodilator-stimulated phosphoprotein (VASP) in human and mouse were isolated, and major parts were sequenced. In both species the gene is composed of 13 exons with conserved exon-intron positions. The mouse VASP cDNA sequence was deduced from the genomic sequence. The predicted amino acid sequence is 89% identical to the human protein. The high nucleotide sequence homology extends not only over the coding regions but also into the 3{prime}-UTRs, indicating a possible function in mRNA targeting or regulation of translation. Prominent 5{prime} CpG islands including multiple SP1 sites indicate a housekeeping function of VASP. Using cosmid DNA as a probe for fluorescence in situ hybridization, the human VASP gene was assigned to chromosome 19q13.2-q13.3, an extended region with homology to mouse chromosome 7. A sequence overlap of the VASP 5{prime}-region with the telomeric end of a cosmid contig physically links the VASP gene with ERCC1. VASP is located about 92 kb distal to ERCC1 and about 300 kb proximal to the myotonic dystrophy protein kinase gene. 43 refs., 6 figs.

  10. Human beta 2 chain of laminin (formerly S chain): cDNA cloning, chromosomal localization, and expression in carcinomas

    DEFF Research Database (Denmark)

    Wewer, U M; Gerecke, D R; Durkin, M E

    1994-01-01

    Overlapping cDNA clones that encode the full-length human laminin beta 2 chain, formerly called the S chain, were isolated. The cDNA of 5680 nt contains a 5391-nt open reading frame encoding 1797 amino acids. At the amino terminus is a 32-amino-acid signal peptide that is followed by the mature...... chain showed 86.1% sequence identity to the rat beta 2 chain, 50.0% to the human beta 1 chain, and 36.3% to the human beta 3 chain. The greatest sequence identity was in domains VI, V, and III. The sequence of a 24-amino-acid peptide fragment isolated from the beta 2 chain of laminin purified from human...

  11. A PCR-free cloning method for the targeted φ80 Int-mediated integration of any long DNA fragment, bracketed with meganuclease recognition sites, into the Escherichia coli chromosome.

    Science.gov (United States)

    Ublinskaya, Anna A; Samsonov, Valeriy V; Mashko, Sergey V; Stoynova, Nataliya V

    2012-06-01

    The genetic manipulation of cells is the most promising strategy for designing microorganisms with desired traits. The most widely used approaches for integrating specific DNA-fragments into the Escherichia coli genome are based on bacteriophage site-specific and Red/ET-mediated homologous recombination systems. Specifically, the recently developed Dual In/Out integration strategy enables the integration of DNA fragments directly into specific chromosomal loci (Minaeva et al., 2008). To develop this strategy further, we designed a method for the precise cloning of any long DNA fragments from the E. coli chromosome and their targeted insertion into the genome that does not require PCR. In this method, the region of interest is flanked by I-SceI rare-cutting restriction sites, and the I-SceI-bracketed region is cloned into the unique I-SceI site of an integrative plasmid vector that then enables its targeted insertion into the E. coli chromosome via bacteriophage φ80 Int-mediated specialized recombination. This approach allows any long specific DNA fragment from the E. coli genome to be cloned without a PCR amplification step and reproducibly inserted into any chosen chromosomal locus. The developed method could be particularly useful for the construction of marker-less and plasmid-less recombinant strains in the biotechnology industry.

  12. Molecular cloning and chromosomal localization of human genes encoding three closely related G protein-coupled receptors

    Energy Technology Data Exchange (ETDEWEB)

    Zhao-Hui Song; Bonner, T.I. [NIMH National Inst. of Health, Bethesda, MD (United States); Modi, W. [Frederick Cancer Research and Development Center, Frederick, MD (United States)

    1995-07-20

    Cosmids containing human genes for orphan G protein-coupled receptors, GPR12, GPR6, and GPR3, were isolated using their rat homologs as probes. Previous studies of the mouse and rat cDNAs have shown the receptors to be expressed primarily in brain but have failed to identify their ligands. The three receptor proteins of 334, 363, and 330 amino acids, respectively, are encoded by a single exon in each gene. Excluding the divergent sequences preceding the first transmembrane domain, they have {approximately}60% amino acid identity with each other. Flurorescence in situ hybridization of GPR12, GPR6, and GPR3 localized these three genes to human chromosomal regions 13q12, 6q21, and 1p34.3-p36.1, respectively. 9 refs., 2 figs.

  13. Construction of a BAC library from cucumber (Cucumis sativus L.) and identification of linkage group specific clones

    Institute of Scientific and Technical Information of China (English)

    Yuan Guan; Qi Chen; Junsong Pan; Zheng Li; Huanle He; Aizhong Wu; Rentao Song; Run Cai

    2008-01-01

    A bacterial artificial chromosome (BAC) library consisting of 19,200 clones with an average insert size of 105 kb has been constructed from a cucumber (Cucumis sativus L.) inbred line S94, derived from a cultivar in North China. The entire library was equivalent to approximately 5 haploid cucumber genomes. To facilitate chromosome engineering and anchor the cucumber genetic linkage map to its chromosomes, 15 sequence-characterized amplified regions (SCAR) and seven simple sequence repeats (SSR) markers from each link-age group of cucumber were used to screen an ordered array of pooled BAC DNA with polymerase chain reaction (PCR). Fifteen mark-ers gave at least two positive clones. As a result, 22 BAC clones representing 7 linkage groups of cucumber were identified, which further validated the genome coverage and utility of the library. This BAC library and linkage group specific clones provide essential resources for future research of the cucumber genome.

  14. Two unisexual artificial polyploid clones constructed by genome addition of common carp (Cyprinus carp) and crucian carp (Carassius auratus)

    Institute of Scientific and Technical Information of China (English)

    WU; Qingjiang; (吴清江); YE; Yuzhen; (叶玉珍); DONG; Xinhong; (董新红)

    2003-01-01

    A polyploid hybrid fish with natural gynogenesis can prevent segregation and maintain their hybrid vigor in their progenies. Supposing the reproduction mode of induced polyploid fish being natural gynogenesis, allopolyploid hybrid between common carp and crucian carp into allopolyploid was performed. The purpose of this paper is to describe a lineage from sexual diploid carp transforming into allotriploid and allotetraploid unisexual clones by genome addition. The diploid hybrid between common carp and crucian carp reproduces an unreduced nucleus consisting of two parental genomes. This unreduced female pronucleus will fuse with male pronucleus and form allotriploid zygote after penetration of related species sperms. Allotriploid embryos grow normally, and part of female allotriploid can produce unreduced mature ova with three genomes. Mature ova of most allotriploid females are provided with natural gynogenetic trait and their nuclei do not fuse with any entrance sperm. All female offspring are produced by gynogenesis of allotriploid egg under activation of penetrating sperms. These offspring maintain morphological traits of their allotriploid maternal and form an allotetraploid unisexual clone by gynogenetic reproduction mode. However, female nuclei of rare allotriploid female can fuse with penetrating male pronuclei and result in the appearance of allotetraploid individuals by means of genome addition. All allotetraploid females can reproduce unreduced mature eggs containing four genomes. Therefore, mature eggs of allotetraploid maintain gynogenetic trait and allotetraploid unisexual clone is produced under activation of related species sperms.

  15. Construction of an Americn mink Bacterial Artificial Chromosome (BAC) library and sequencing candidate genes important for the fur industry

    DEFF Research Database (Denmark)

    Anistoroaei, Razvan Marian; Hallers, Boudewijn ten; Nefedov, Michael;

    2011-01-01

    consisting of 18,432 clones spotted in duplicate, have been produced for hybridization screening and are publicly available. Overgo probes derived from expressed sequence tags (ESTs), representing 21 candidate genes for traits important for the mink industry, were used to screen the BAC library...

  16. Physical maps and recombination frequency of six rice chromosomes.

    Science.gov (United States)

    Wu, Jianzhong; Mizuno, Hiroshi; Hayashi-Tsugane, Mika; Ito, Yukiyo; Chiden, Yoshino; Fujisawa, Masaki; Katagiri, Satoshi; Saji, Shoko; Yoshiki, Shoji; Karasawa, Wataru; Yoshihara, Rie; Hayashi, Akiko; Kobayashi, Harumi; Ito, Kazue; Hamada, Masao; Okamoto, Masako; Ikeno, Maiko; Ichikawa, Yoko; Katayose, Yuichi; Yano, Masahiro; Matsumoto, Takashi; Sasaki, Takuji

    2003-12-01

    We constructed physical maps of rice chromosomes 1, 2, and 6-9 with P1-derived artificial chromosome (PAC) and bacterial artificial chromosome (BAC) clones. These maps, with only 20 gaps, cover more than 97% of the predicted length of the six chromosomes. We submitted a total of 193 Mbp of non-overlapping sequences to public databases. We analyzed the DNA sequences of 1316 genetic markers and six centromere-specific repeats to facilitate characterization of chromosomal recombination frequency and of the genomic composition and structure of the centromeric regions. We found marked changes in the relative recombination rate along the length of each chromosome. Chromosomal recombination at the centromere core and surrounding regions on the six chromosomes was completely suppressed. These regions have a total physical length of about 23 Mbp, corresponding to 11.4% of the entire size of the six chromosomes. Chromosome 6 has the longest quiescent region, with about 5.6 Mbp, followed by chromosome 8, with quiescent region about half this size. Repetitive sequences accounted for at least 40% of the total genomic sequence on the partly sequenced centromeric region of chromosome 1. Rice CentO satellite DNA is arrayed in clusters and is closely associated with the presence of Centromeric Retrotransposon of Rice (CRR)- and RIce RetroElement 7 (RIRE7)-like retroelement sequences. We also detected relatively small coldspot regions outside the centromeric region; their repetitive content and gene density were similar to those of regions with normal recombination rates. Sequence analysis of these regions suggests that either the amount or the organization patterns of repetitive sequences may play a role in the inactivation of recombination.

  17. Molecular cloning, expression analysis and chromosomal mapping of salt-responsive cDNAs in rice ( Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    李子银; 张劲松; 陈受宜

    1999-01-01

    By using differential display PCR (DD-PCR) technique, two salt-inducible and one salt-repressed cDNA fragments were isolated from rice. The three eDNA fragments were characterized respectively as partial sequence of rice S-adenosylmethionine deearboxylase (SAMDC) gene, a new member of translation elongation factor 1A gene (named REF1A ), and a novel gene whose function is unknown (named SRG1). The full-length cDNA of SAMDC gene (named SAMDC1) was further isolated by RT-PCR approach and the deduced polypeptide was found to be homologous to SAMDC proteins of other plants, yeast and human. Northern hybridization revealed that expression of SAMDC1 and REF1A was induced, while SRG1 was dramatically repressed, by salinity stress. Southern blot analysis demonstrated that SAMDC1 and SRG1 were present as a single copy gene in rice genome, whereas rice REF1A gene was organized as a gene family. The REF1A, SAMDC1, and SRG1 genes were located on chromosome 3, 4, and 6 respectively by RFLP mapping approach using ZYQ

  18. Human platelet/erythroleukemia cell prostaglandin G/H synthase: cDNA cloning, expression, and gene chromosomal assignment

    Energy Technology Data Exchange (ETDEWEB)

    Funk, C.D.; Funk, L.B.; Kennedy, M.E.; Pong, A.S.; Fitzgerald, G.A. (Vanderbilt Univ., Nashville, TN (United States))

    1991-06-01

    Platelets metabolize arachidonic acid to thromboxane A{sub 2}, a potent platelet aggregator and vasoconstrictor compound. The first step of this transformation is catalyzed by prostaglandin (PG) G/H synthase, a target site for nonsteroidal antiinflammatory drugs. We have isolated the cDNA for both human platelet and human erythroleukemia cell PGG/H synthase using the polymerase chain reaction and conventional screening procedures. The cDNA encoding the full-length protein was expressed in COS-M6 cells. Microsomal fractions from transfected cells produced prostaglandin endoperoxide derived products which were inhibited by indomethacin and aspirin. Mutagenesis of the serine residue at position 529, the putative aspirin acetylation site, to an asparagine reduced cyclooxygenase activity to barely detectable levels, an effect observed previously with the expressed sheep vesicular gland enzyme. Platelet-derived growth factor and phorbol ester differentially regulated the expression of PGG/H synthase mRNA levels in the megakaryocytic/platelet-like HEL cell line. The PGG/H synthase gene was assigned to chromosome 9 by analysis of a human-hamster somatic hybrid DNA panel. The availability of platelet PGG/H synthase cDNA should enhance our understanding of the important structure/function domains of this protein and it gene regulation.

  19. Generation of chicken Z-chromosome painting probes by microdissection for screening large-insert genomic libraries.

    Science.gov (United States)

    Zimmer, R; King, W A; Verrinder Gibbins, A M

    1997-01-01

    A strategy for rapid generation of chicken sex chromosome-Z painting probes has been developed using microdissection. Whole chromosome painting probes (WCPs) were prepared from 10-15 copies of mitotic metaphase chicken Z chromosomes. The microisolated chromosomes were subjected to PEG/proteinase K treatment in a collection drop to release DNA, which was then amplified using a degenerate oligonucleotide-primed shuttle PCR (DOP-Shuttle-PCR) strategy. Size distributions of the PCR products were analyzed by agarose gel electrophoresis and smears of DNA were revealed that ranged in size from 200-800 bp, without any evidence of preferential amplification. Both specificity and complexity of the probes have been analyzed by Southern blot and fluorescence in situ hybridization (FISH). Non-specific hybridization was efficiently blocked by using chicken competitor DNA. Analysis of the WCPs produced shows that collectively they provide uniform hybridization signals along the entire length of the chicken Z chromosome. To demonstrate one possible application of these complex probes, we screened a large-insert bacterial artificial chromosome (BAC) chicken genomic library to select Z chromosome-specific clones. To address specificity of the selected clones and to physically map them to the Z chromosome, FISH analysis was used. Of the 3 clones initially tested, one clone (C3) carrying a 250-kb insert mapped to the distal portion of the short arm of the chicken Z chromosome. Therefore, this technique has provided appropriate probes for screening large-insert genomic libraries. Further application of these probes includes the analysis of chromosome rearrangements, studies of cases of heteroploidy involving the Z chromosome, positional cloning of Z-linked genes and studies on mechanisms of sex-chromosome evolution in birds.

  20. cDNA cloning, tissue distribution, and chromosomal localization of Ocp2, a gene encoding a putative transcription-associated factor predominantly expressed in the auditory organs

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hong; Thalmann, I.; Thalmann, R. [Washington Univ., St. Louis, MO (United States)] [and others

    1995-06-10

    We report the cloning of the Ocp2 gene encoding OCP-II from a guinea pig organ-of-Corti cDNA library. The predicted open reading frame encodes a protein of 163 amino acids with an estimated molecular mass of 18.6 kDa. A homology search revealed that Ocp2 shares significant sequence similarity with p15, a sub-unit of transcription factor SIII that regulates the activity of the RNA polymerase II elongation complex. The Ocp2 messenger RNA is expressed abundantly in the cochlea while not significantly in any other tissues examined, including brain, eye, heart, intestine, kidney, liver, lung, thigh muscle, and testis, demonstrating that the expression of this gene may be restricted to auditory organs. A polyclonal antiserum was raised against the N-terminal region of OCP-II. Immunohistochemical staining of paraffin-embedded sections of the cochlea showed that OCP-II is localized abundantly in nonsensory cells in the organ of Corti; in addition, it was also detected, at a lower concentration, in vestibular sensory organs, as well as auditory and vestibular brain stem nuclei. The Ocp2 gene was mapped to mouse chromosome 4 as well as 11. Our results suggest that OCP-II may be involved in transcription regulation for the development or maintenance of specialized functions of the inner ear. 40 refs., 5 figs.

  1. Molecular cloning of the cDNA and chromosomal localization of the gene for a putative seven-transmembrane segment (7-TMS) receptor isolated from human spleen

    Energy Technology Data Exchange (ETDEWEB)

    Federsppiel, B.; Melhado, I.G.; Delaney, A.; Clark-Lewis, I. (Univ. of British Columbia, Vancouver (Canada)); Duncan, A.M.V. (Queens Univ., Kinston, Ontario (Canada)); Jirik, F.R. (Hospital for Sick Children, Toronto, Ontario (Canada))

    1993-06-01

    A family of proinflammatory cytokines sharing several structural features has been described and includes, for example, interleukin-8, monocyte chemoattractant protein-1, and melanocyte growth stimulatory activity. Recently, the receptors for interleukin-8 have been isolated and found to belong to the seven-transmembrane domain class of G protein-coupled receptors. As other members of this cytokine family likely interact with similar receptors, the polymerase chain reaction was employed to isolate related receptors from human peripheral blood adherent cells. Degenerate oligonucleotide primers based on the rabbit interleukin-8 receptor sequence were used. The corresponding full-length cDNA was isolated from a human spleen cDNA library. The predicted protein sequence of this clone, designated pBE1.3, was 93% identical to that of a cDNA isolated from bovine locus coeruleus, which apparently encodes a neuropeptide Y receptor, and also shows similarity with the interleukin-8 receptor and the human cytomegalovirus US28 sequences. The gene, designated D2S201E, was localized to human chromosome 2q21. By Northern blotting, transcripts hybridizing to this cDNA were present in a variety of tissues and cells, including those of hemopoietic origin. 32 refs., 5 figs.

  2. First Birth after Sperm Selection through Discontinuous Gradient Centrifugation and Artificial Insemination from a Chromosomal Translocation Carrier

    Directory of Open Access Journals (Sweden)

    Alexandre Rouen

    2014-01-01

    Full Text Available Introduction. Balanced chromosomal carriers, though usually healthy, are confronted with recurrent spontaneous abortions and malformations in the offspring. Those are related to the transmission of an abnormal, chromosomally unbalanced genotype. We evidenced that the proportion of unbalanced spermatozoa can be significantly decreased through a sperm preparation process called discontinuous gradient centrifugation (DGC. We therefore started offering intrauterine inseminations with this procedure to couples with a male translocation carriers. Case Presentation. We report the case of a 37-year-old man carrying a t(3;10(q25;p13 reciprocal translocation. He and his partner had had trouble conceiving for ten years and had four spontaneous abortions. DGC in this patient decreased the proportion of unbalanced spermatozoa from 63.6% to 52.3%. They were therefore offered intrauterine insemination with DGC, which eventually led to the birth of a healthy female child carrying the paternal translocation. Conclusion. We showed that translocation carriers could be offered intrauterine inseminations with DGC. Before this, the only two options were natural conception with prenatal diagnosis and termination of chromosomally unbalanced fetuses or preimplantation genetic diagnosis, which is a much heavier and costly procedure. We are currently offering this option through a multicentric program in France, and this is the first birth originating from it.

  3. Molecular cloning, genomic organization, chromosome mapping, tissues expression pattern and identification of a novel splicing variant of porcine CIDEb gene.

    Science.gov (United States)

    Li, YanHua; Li, AiHua; Yang, Z Q

    2016-09-09

    Cell death-inducing DNA fragmentation factor-α-like effector b (CIDEb) is a member of the CIDE family of apoptosis-inducing factors, CIDEa and CIDEc have been reported to be Lipid droplets (LDs)-associated proteins that promote atypical LD fusion in adipocytes, and responsible for liver steatosis under fasting and obese conditions, whereas CIDEb promotes lipid storage under normal diet conditions [1], and promotes the formation of triacylglyceride-enriched VLDL particles in hepatocytes [2]. Here, we report the gene cloning, chromosome mapping, tissue distribution, genetic expression analysis, and identification of a novel splicing variant of the porcine CIDEb gene. Sequence analysis shows that the open reading frame of the normal porcine CIDEb isoform covers 660bp and encodes a 219-amino acid polypeptide, whereas its alternative splicing variant encodes a 142-amino acid polypeptide truncated at the fourth exon and comprised of the CIDE-N domain and part of the CIDE-C domain. The deduced amino acid sequence of normal porcine CIDEb shows an 85.8% similarity to the human protein and 80.0% to the mouse protein. The CIDEb genomic sequence spans approximately 6KB comprised of five exons and four introns. Radiation hybrid mapping demonstrated that porcine CIDEb is located at chromosome 7q21 and at a distance of 57cR from the most significantly linked marker, S0334, regions that are syntenic with the corresponding region in the human genome. Tissue expression analysis indicated that normal CIDEb mRNA is ubiquitously expressed in many porcine tissues. It was highly expressed in white adipose tissue and was observed at relatively high levels in the liver, lung, small intestine, lymphatic tissue and brain. The normal version of CIDEb was the predominant form in all tested tissues, whereas the splicing variant was expressed at low levels in all examined tissues except the lymphatic tissue. Furthermore, genetic expression analysis indicated that CIDEb mRNA levels were

  4. Analysis of plant meiotic chromosomes by chromosome painting.

    Science.gov (United States)

    Lysak, Martin A; Mandáková, Terezie

    2013-01-01

    Chromosome painting (CP) refers to visualization of large chromosome regions, entire chromosome arms, or entire chromosomes via fluorescence in situ hybridization (FISH). For CP in plants, contigs of chromosome-specific bacterial artificial chromosomes (BAC) from the target species or from a closely related species (comparative chromosome painting, CCP) are typically applied as painting probes. Extended pachytene chromosomes provide the highest resolution of CP in plants. CP enables identification and tracing of particular chromosome regions and/or entire chromosomes throughout all meiotic stages as well as corresponding chromosome territories in premeiotic interphase nuclei. Meiotic pairing and structural chromosome rearrangements (typically inversions and translocations) can be identified by CP. Here, we describe step-by-step protocols of CP and CCP in plant species including chromosome preparation, BAC DNA labeling, and multicolor FISH.

  5. A major barley allergen associated with baker's asthma disease is a glycosylated monomeric inhibitor of insect alpha-amylase: cDNA cloning and chromosomal location of the gene.

    Science.gov (United States)

    Mena, M; Sanchez-Monge, R; Gomez, L; Salcedo, G; Carbonero, P

    1992-11-01

    A 14.5 kDa barley endosperm protein that is a major allergen in baker's asthma disease, as previously shown by both in vitro (IgE binding) and in vivo tests, has been identified as a glycosylated monomeric member of the multigene family of inhibitors of alpha-amylase/trypsin from cereals. A cDNA encoding this allergen (renamed BMAI-1) has been isolated and characterized. The deduced sequence for the mature protein, which is 132 residues long, is identical in its N-terminal end to the 20 amino acid partial sequence previously determined from the purified allergen, and fully confirms that it is a member of the multigene family of cereal inhibitors. Southern-blot analysis of wheat/barley addition lines using the insert in the BMAI-1 cDNA clone as a probe, has led to the location of the allergen gene (Iam1) in barley chromosome 2, while another related member of this protein family, the barley dimeric alpha-amylase inhibitor BDAI-1 gene (Iad1) has been located in chromosome 6. Iam1 is the first member of this inhibitor family in cereals to be assigned to chromosome group 2, thus extending the dispersion of genes in the family to five out of the seven homology groups of chromosomes in wheat and barley (chromosomes 2, 3, 4, 6 and 7).

  6. A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome.

    Directory of Open Access Journals (Sweden)

    Teruhiko Suzuki

    Full Text Available Human artificial chromosomes (HACs are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming.

  7. A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome.

    Science.gov (United States)

    Suzuki, Teruhiko; Kazuki, Yasuhiro; Oshimura, Mitsuo; Hara, Takahiko

    2014-01-01

    Human artificial chromosomes (HACs) are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV) into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system) via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming.

  8. Chromosome-specific DNA Repeat Probes

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, Adolf; Weier, Jingly Fung; Weier, Heinz-Ulrich G.

    2006-03-16

    In research as well as in clinical applications, fluorescence in situ hybridization (FISH) has gained increasing popularity as a highly sensitive technique to study cytogenetic changes. Today, hundreds of commercially available DNA probes serve the basic needs of the biomedical research community. Widespread applications, however, are often limited by the lack of appropriately labeled, specific nucleic acid probes. We describe two approaches for an expeditious preparation of chromosome-specific DNAs and the subsequent probe labeling with reporter molecules of choice. The described techniques allow the preparation of highly specific DNA repeat probes suitable for enumeration of chromosomes in interphase cell nuclei or tissue sections. In addition, there is no need for chromosome enrichment by flow cytometry and sorting or molecular cloning. Our PCR-based method uses either bacterial artificial chromosomes or human genomic DNA as templates with {alpha}-satellite-specific primers. Here we demonstrate the production of fluorochrome-labeled DNA repeat probes specific for human chromosomes 17 and 18 in just a few days without the need for highly specialized equipment and without the limitation to only a few fluorochrome labels.

  9. Cloning and characterization of human very-long-chain acyl-CoA dehydrogenase cDNA, chromosomal assignment of the gene and identification in four patients of nine different mutations within the VLCAD gene

    DEFF Research Database (Denmark)

    Andresen, B S; Bross, P; Vianey-Saban, C;

    1996-01-01

    extensive sequence homology corroborating the notion that these genes are evolutionarily related. Southern blot analysis of genomic DNA from hybrid cell lines was used to localize the VLCAD gene to human chromosome 17p11.2-p11.13105. Using Northern and Western blot analysis to investigate the tissue...... specific distribution of VLCAD mRNA and protein in several human tissues we showed that VLCAD is most abundant in heart and skeletal muscle. This agrees well with the fact that cardiac and muscle symptoms are characteristic for patients with VLCAD deficiency. Northern blot analysis and sequencing of cloned...

  10. A new implementation of high-throughput five-dimensional clone pooling strategy for BAC library screening

    Directory of Open Access Journals (Sweden)

    Deal Karin R

    2010-12-01

    Full Text Available Abstract Background A five-dimensional (5-D clone pooling strategy for screening of bacterial artificial chromosome (BAC clones with molecular markers utilizing highly-parallel Illumina GoldenGate assays and PCR facilitates high-throughput BAC clone and BAC contig anchoring on a genetic map. However, this strategy occasionally needs manual PCR to deconvolute pools and identify truly positive clones. Results A new implementation is reported here for our previously reported clone pooling strategy. Row and column pools of BAC clones are divided into sub-pools with 1~2× genome coverage. All BAC pools are screened with Illumina's GoldenGate assay and the BAC pools are deconvoluted to identify individual positive clones. Putative positive BAC clones are then further analyzed to find positive clones on the basis of them being neighbours in a contig. An exhaustive search or brute force algorithm was designed for this deconvolution and integrated into a newly developed software tool, FPCBrowser, for analyzing clone pooling data. This algorithm was used with empirical data for 55 Illumina GoldenGate SNP assays detecting SNP markers mapped on Aegilops tauschii chromosome 2D and Ae. tauschii contig maps. Clones in single contigs were successfully assigned to 48 (87% specific SNP markers on the map with 91% precision. Conclusion A new implementation of 5-D BAC clone pooling strategy employing both GoldenGate assay screening and assembled BAC contigs is shown here to be a high-throughput, low cost, rapid, and feasible approach to screening BAC libraries and anchoring BAC clones and contigs on genetic maps. The software FPCBrowser with the integrated clone deconvolution algorithm has been developed and is downloadable at http://avena.pw.usda.gov/wheatD/fpcbrowser.shtml.

  11. Identification of Chromosomes from Multiple Rice Genomes Using a Universal Molecular Cytogenetic Marker System

    Institute of Scientific and Technical Information of China (English)

    Xiaomin Tang; Weidong Bao; Wenli Zhang; Zhukuan Cheng

    2007-01-01

    To develop reliable techniques for chromosome identification is critical for cytogenetic research, especially for genomes with a large number and smaller-sized chromosomes. An efficient approach using bacterial artificial chromosome (BAG) clones as molecular cytological markers has been developed for many organisms. Herein, we present a set of chromosomal arm-specific molecular cytological markers derived from the gene-enriched regions of the sequenced rice genome. All these markers are able to generate very strong signals on the pachytene chromosomes of Oryza satlva L. (AA genome) when used as fluorescence in situ hybridization (FISH) probes. We further probed those markers to the pachytene chromosomes of O. punctata (BB genome) and O. officinalis (CC genome) and also got very strong signals on the relevant pachytene chromosomes. The signal position of each marker on the related chromosomes from the three different rice genomes was pretty much stable, which enabled us to identify different chromosomes among various rice genomes. We also constructed the karyotype for both O. punctata and O. officinalis with the BB and CC genomes, respectively, by analysis of 10 pachytene cells anchored by these chromosomal arm-specific markers.

  12. Phosphoribosylpyrophosphate synthetase of Bacillus subtilis. Cloning, characterization and chromosomal mapping of the prs gene

    DEFF Research Database (Denmark)

    Nilsson, Dan; Hove-Jensen, Bjarne

    1987-01-01

    The gene (prs) encoding phosphoribosylpyrophosphate (PRPP) synthetase has been cloned from a library of Bacillus subtilis DNA by complementation of an Escherichia coli prs mutation. Flanking DNA sequences were pruned away by restriction endonuclease and exonuclease BAL 31 digestions, resulting...

  13. NotI jumping and linking clones as a tool for genome mapping and analysis of chromosome rearrangements in different tumors.

    Science.gov (United States)

    Zabarovsky, E R; Kashuba, V I; Gizatullin, R Z; Winberg, G; Zabarovska, V I; Erlandsson, R; Domninsky, D A; Bannikov, V M; Pokrovskaya, E; Kholodnyuk, I; Petrov, N; Zakharyev, V M; Kisselev, L L; Klein, G

    1996-01-01

    Long-range restriction site maps are of central importance for mapping the human genome. The use of clones from linking and jumping libraries for genome mapping offers a promising alternative to the laborious procedures used up until now. In the present review, this research field is analyzed with particular emphasis on the implementation of a shot-gun sequencing strategy for genome mapping and the use of NotI linking clones for analysis of rearrangements in tumors and tumor cell lines.

  14. ADVANCES IN REPRODUCTIVE TECHNOLOGIES IN CATTLE: FROM ARTIFICIAL INSEMINATION TO CLONING AVANCES EN BIOTECNOLOÍA REPRODUCTIVA EN BOVINOS: DE LA INSEMINACIÓN ARTIFICIAL A LA CLONACIÓN

    Directory of Open Access Journals (Sweden)

    Bertolini, L.R

    2009-05-01

    Full Text Available The urge for the control of reproductive processes in animals has propelled a great gain in knowledge, also setting off the development of four generations of assisted reproductive technologies (AR T for humans and animals. The use of assisted reproductive techniques has been of great importance in livestock production. In general terms, the main first three generations of ARTs, including 1 artificial insemination (AI and gamete and embryo freezing, 2 multiple ovulation and embryo transfer (MOET and 3 in vitro fertilization (IV F procedures, have matured into successful commercial applications, facilitating the increase in production through genetics, the reduction in generation intervals, the control of diseases, and the cutback in production costs. The fourth generation of AR T encompasses processes that are still more experimental, comprising cloning by nuclear transfer (NT of embryonic or somatic cells, transgenesis, and stem cell biology. Such technologies are intertwined with one another and with currently available molecular tools, being completely dependent upon the previous generations of technologies. However, many reproductive challenges still hinder maximal livestock reproductive performance, affecting productivity and profitability. It is clear that the application of such technologies as lucrative activities will remain questionable if not associated with other components of animal production, such as animal health, nutrition and adequate animal husbandry practices.El afán por controlar los procesos reproductivos en animales ha llevado a una gran ganancia en conocimiento, impulsando el desarrollo de cuatro tecnologías reproductivas asistidas (AR Ts para animales y humanos. El uso de AR Ts ha sido de gran importancia en la producción ganadera. En términos generales, las tres principales generaciones de AR T, incluyendo 1 inseminación artificial (AI y congelación de gametos y embriones, 2 superovulación y transferencia de

  15. Chromosome doubling in early spermatogonia produces diploid spermatozoa in a natural clonal fish.

    Science.gov (United States)

    Yoshikawa, Hiroyuki; Morishima, Kagayaki; Fujimoto, Takafumi; Saito, Taiju; Kobayashi, Tohru; Yamaha, Etsuro; Arai, Katsutoshi

    2009-05-01

    The natural clonal loach Misgurnus anguillicaudatus (Teleostei: Cobitidae) is diploid (2n = 50) and produces genetically identical unreduced eggs, which develop into diploid individuals without any genetic contribution from sperm. Artificially sex-reversed clones created by the administration of 17alpha-methyltestosterone produce clonal diploid sperm. In metaphase spreads from testicular cells of the sex-reversed clones, spermatocytes had twice the normal number of chromosomes (50 bivalents) compared with those of normal diploids (25 bivalents). Thus, the production of unreduced diploid spermatozoa is initiated by premeiotic endomitosis (or endoreduplication), chromosome doubling before meiosis, and is followed by two quasinormal divisions. Larger nuclei in the germ cells were observed in all stages of type B spermatogonia in the testes of the sex-reversed clones. In contrast, besides having larger type A spermatogonia, the sex-reversed clones also had the type A spermatogonia that were the same size as those of normal diploids. It follows that chromosome duplication causing unreduced spermatogenesis occurred in the type A spermatogonia. The presence of tetraploid type A and early type B spermatogonia, identified by labeling with antispermatogonia-specific antigen 1, was verified using DNA content flow cytometry. These results support the conclusion that chromosome doubling occurs at the type A spermatogonial stage in diploid spermatogenesis in the clonal fish.

  16. [Developing a physical map of human chromosome 22 using Pace electrophoresis and large fragment cloning]. Annual report, October 1, 1989--September 30, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Simon, M.I.

    1990-12-31

    In the past year the authors have made significant progress in the development of a bacterial based cloning system for large fragments of mammalian DNA. They have completed construction of several recombination deficient bacterial host strains designed to minimize homologous recombination arising with repeats within cloned DNA. Despite the multiple mutations, these strains are viable and grow readily on standard media (LB). One of the chief attractions of a bacterial system is the promise of high transformation efficiencies. The author have pursued two separate strategies with the vector. The first makes use of the cos sites in the vector to package cloned DNA as phage particles for infection. By maintaining the vector as a single copy in the recombination minus host, they believe that the recombination that affects conventional cosmid libraries will be eliminated. They encountered no difficulties in preparing such a ``Fosmid`` (F factor based cosmid) library of human DNA.

  17. Why Clone?

    Science.gov (United States)

    ... How might cloning be used in medicine? Cloning animal models of disease Much of what researchers learn ... issue of the genetic reshuffling that happensduring sexual reproduction and simply clone our drug-producing cow. Cloning ...

  18. Construction of A Bacterial Artificial Chromosome (BAC) Contig Encompassing the Bacterial Blight Resistance Gene Xa4 Locus in Rice%水稻抗白叶枯病基因Xa4位点跨叠BAC克隆群的构建

    Institute of Scientific and Technical Information of China (English)

    江光怀; 王文明; 谢兵; 翟文学; 鲁润龙; 朱立煌

    2001-01-01

    The gene Xa4 confers dominantly resistance to rice bacterialblight, which has been finely mapped between RFLP markers G181 and L1044, and co-segregated with the resistance gene homologues sequence marker RS13. The three markers were used to screen a rice Bacterial Artificial Chromosome (BAC) library constructed from IRBB56, a Xa4-harborring indica variety, resulting in the detection of totally 128 positive clones. Of the 18 positive clones picked out by RS13, 4 and 6 clones were simultaneously detected by G181 and L1044, respectively. Based on their Hindrestriction patterns, 12 clones were selected out to construct a contig that spanned about 420 kb covering the Xa4 locus, which is a solid base for the isolation of Xa4 gene.%水稻白叶枯病抗性基因Xa4已被定位于第11染色体长臂末端的分子标记G181和L1044之间,并与抗性基因同源序列片段RS13共分离。利用这3个标记筛选IRBB56的BAC文库,共得到128个阳性BAC克隆,其中RS13获得18个阳性克隆,这18个克隆中有4个和6个克隆分别同时为G181和L1044的阳性克隆。选其中的12个克隆进行分析,构建了一个从G181到L1044区间的BAC跨叠克隆群,全长420kb,并且56M22、106P13和104B153个BAC克隆可覆盖整个跨叠克隆群。这一研究结果为进一步分离Xa4基因打下了基础。

  19. Identification of a yeast artificial chromosome (YAC) spanning the synovial sarcoma-specific t(X;18)(p11.2;q11.2) breakpoint

    NARCIS (Netherlands)

    de Leeuw, B; Berger, W; Sinke, R J; Suijkerbuijk, R F; Gilgenkrantz, S; Geraghty, M T; Valle, D; Monaco, A P; Lehrach, H; Ropers, H H

    1993-01-01

    A somatic cell hybrid containing the synovial sarcoma-associated t(X;18)(p11.2;q11.2) derivative (der(X)) chromosome was used to characterize the translocation breakpoint region on the X chromosome. By using Southern hybridization of DNA from this der(X) hybrid in conjunction with Xp-region specific

  20. Tripeptidase Gene (pepT) of Lactococcus lactis : Molecular Cloning and Nucleotide Sequencing of pepT and Construction of a Chromosomal Deletion Mutant

    NARCIS (Netherlands)

    Mierau, Igor; Haandrikman, Alfred J.; Velterop, Odilia; Tan, Paris S.T.; Leenhouts, Kees L.; Konings, Wilhelmus; Venema, Gerhardus; Kok, Jan

    1994-01-01

    The gene encoding a tripeptidase (pepT) of lactococcus lactis subsp. cremoris (formerly subsp. lactis) MG1363 was cloned from a genomic library in pUC19 and subsequently sequenced. The tripeptidase of L. lactis was shown to be homologous to PepT of Salmonella typhimurium with 47.4% identity in the d

  1. Sequence composition of BAC clones and SSR markers mapped to Upland cotton chromosomes 11 and 21 targeting resistance to soil-borne pathogens

    Science.gov (United States)

    Genetic and physical framework mapping in cotton (Gossypium spp.) were used to discover putative gene sequences involved in resistance to common soil-borne pathogens. Chromosome (Chr) 11 and its homoeologous Chr 21 of Upland cotton (G. hirsutum) is a focus for discovery of resistance (R) or pathoge...

  2. Detection of the Integration of Human Transferrin Gene on Chromosomes in Transgenic Cloned Cows%人转铁蛋白转基因克隆牛整合位点检测

    Institute of Scientific and Technical Information of China (English)

    刘宇; 朱怡文; 许淼; 黄英

    2012-01-01

    为检测外源基因整合在转基因克隆牛染色体上的定位情况,通过优化染色体荧光原位杂交技术,成功对4头人转铁蛋白转基因克隆牛的整合位点进行定位.每头牛分析中期分裂相40个以上,杂交率在53.1%~86.8%之间,且杂交信号分别位于转基因克隆牛的11号、15号和19号染色体的相应位置;另外采用定量PCR方法对杂交信号强弱不同的转基因克隆牛个体进行整合位点拷贝数的检测,结果显示拷贝数的多少与杂交信号强弱直接有关.%To detect the integration of human transferrin gene(hTF) on chromosomes in transgenic cloned cows.the author optimized fluorescence in situ hybridization(FISH). For transgenic cloned cows,53. 1% to 86. 8% of metaphases showed hybridization signals which were located on different chromosomes,such as Chr. 11, Chr. 15 and Chr. 19. The results showed that using FISH to detect the integration site and hybridization signals was highly efficient and specific,also the copy numbers were detected by Real-time PCR.

  3. Protective efficacy of a recombinant bacterial artificial chromosome clone of a very virulent Marek’s disease virus containing a reticuloendotheliosis virus long terminal repeat

    Science.gov (United States)

    Marek’s disease virus (MDV), an alphaherpesvirus, causes Marek’s disease (MD), a lymphoproliferative disease in poultry characterized by T-cell lymphomas, nerve lesions and mortality. Vaccination is used worldwide to control MD, but increasingly virulent field strains can overcome this protection, d...

  4. Insertion of reticuloendotheliosis virus long terminal repeat into a bacterial artificial chromosome clone of a very virulent Marek's disease virus alters its pathogenicity

    Science.gov (United States)

    Co-cultivation of strain JM/102W of Marek’s disease virus (MDV) with reticuloendotheliosis virus (REV) resulted in the generation of a recombinant MDV containing REV long terminal repeat (LTR) named RM1 strain of MDV; a strain that was highly attenuated for oncogenicity, but induced severe bursal an...

  5. Cloning of the cDNA for the human ATP synthase OSCP subunit (ATP5O) by exon trapping and mapping to chromosome 21q22.1-q22.2

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Haiming [Geneva Univ. Medical School (Switzerland); Morris, M.A.; Rossier, C. [Cantonal Hospital, Geneva (Switzerland)] [and others

    1995-08-10

    Exon trapping was used to clone portions of potential genes from human chromosome 21. One trapped sequence showed striking homology with the bovine and rat ATP synthase OSCP (oligomycin sensitivity conferring protein) subunit. We subsequently cloned the full-length human ATP synthase OSCP cDNA (GDB/HGMW approved name ATP50) from infant brain and muscle libraries and determined its nucleotide and deduced amino acid sequence (EMBL/GenBank Accession No. X83218). The encoded polypeptide contains 213 amino acids, with more than 80% identity to bovine and murine ATPase OSCP subunits and over 35% identity to Saccharomyces cerevisiae and sweet potato sequences. The human ATP5O gene is located at 21q22.1-q22.2, just proximal to D21S17, in YACs 860G11 and 838C7 of the Chumakov et al. YAC contig. The gene is expressed in all human tissues examined, most strongly in muscle and heart. This ATP5O subunit is a key structural component of the stalk of the mitochondrial respiratory chain F{sub 1}F{sub 0}-ATP synthase and as such may contribute in a gene dosage-dependent manner to the phenotype of Down syndrome (trisomy 21). 39 refs., 5 figs.

  6. Expression cloning and chromosomal mapping of the leukocyte activation antigen CD97, a new seven-span transmembrane molecule of the secretin receptor superfamily with an unusual extracellular domain

    Energy Technology Data Exchange (ETDEWEB)

    Hamann, J. [Univ. of Amsterdam (Netherlands)]|[Max Planck Society, Berlin-Buch (Germany); Hamann, D.; Lier, R.A.W. [Univ. of Amsterdam (Netherlands)] [and others

    1995-08-15

    CD97 is a monomeric glycoprotein of 75 to 85 kDa that is induced rapidly on the surface of most leukocytes upon activation. We herein report the isolation of a cDNA encoding human CD97 by expression cloning in COS cells. The 3-kb cDNA clone encodes a mature polypeptide chain of 722 amino acids with a predicted molecular mass of 79 kDa. Within the C-terminal part of the protein, a region with seven hydrophobic segments was identified, suggesting that CD97 is a seven-span transmembrane molecule. Sequence comparison indicates that CD97 is the first leukocyte Ag in a recently described superfamily that includes the receptors for secretin, calcitonin, and other mammalian and insect peptide hormones. Different from these receptors, CD97 has an extended extracellular region of 433 amino acids that possesses three N-terminal epidermal growth factor-like domains, two of them with a calcium-binding site, and single Arg-Gly-Asp (RGD) motif. The existence of structural elements characteristic for extracellular matrix proteins in a seven-span transmembrane molecule makes CD97 a receptor potentially involved in both adhesion and signaling processes early after leukocyte activation. The gene encoding CD97 is localized on chromosome 19 (19p13.12-13.2).

  7. Characterisation of the chromosome fusions in Oreochromis karongae.

    Science.gov (United States)

    Mota-Velasco, Jose C; Ferreira, Irani Alves; Cioffi, Marcelo B; Ocalewicz, Konrad; Campos-Ramos, Rafael; Shirak, Andrey; Lee, Bo-Young; Martins, Cesar; Penman, David J

    2010-07-01

    Oreochromis karongae, one of the "chambo" tilapia species from Lake Malawi, has a karyotype of 2n = 38, making it one of the few species investigated to differ from the typical tilapia karyotype (2n = 44). The O. karongae karyotype consists of one large subtelocentric pair of chromosomes, four medium-sized pairs (three subtelocentric and one submetacentric) and 14 small pairs. The five largest pairs could be distinguished from each other on the basis of size, morphology and a series of fluorescence in situ hybridisation (FISH) probes. The largest pair is easily distinguished on the basis of size and a chromosome 1 (linkage group 3) bacterial artificial chromosome (BAC) FISH probe from Oreochromis niloticus. BAC clones from O. niloticus chromosome 2 (linkage group 7) hybridised to one of the medium-sized subtelocentric chromosome pairs (no. 5) of O. karongae, distinguishing the ancestral medium-sized pair from the three other medium-sized chromosome pairs (nos. 2, 3 and 4) that appear to have resulted from fusions. SATA repetitive DNA hybridised to the centromeres of all 19 chromosome pairs and also revealed the locations of the relic centromeres in the three fused pairs. Telomeric (TTAGGG)(n) repeats were identified in the telomeres of all chromosomes, and an interstitial telomeric site (ITS) was identified in three chromosomal pairs (no. 2, 3 and 4). Additionally, two ITS sites were identified in the largest chromosome pair (pair 1), confirming the origin of this chromosome from three ancestral chromosomes. SATA and ITS sites allowed the orientation of the fusions in pairs 2, 3 and 4, which all appear to have been in different orientations (q-q, p-q and p-p, respectively). One of these fusions (O. karongae chromosome pair no. 2) involves a small chromosome (equivalent to linkage group 1), which in O. niloticus carries the main sex-determining gene. 4',6-Diamidino-2-phenyloindole staining of the synaptonemal complex in male O. karongae revealed the presumptive

  8. Cloning of a conserved receptor-like protein kinase gene and its use as a functional marker for homoeologous group-2 chromosomes of the triticeae species.

    Directory of Open Access Journals (Sweden)

    Bi Qin

    Full Text Available Receptor-like kinases (RLKs play broad biological roles in plants. We report on a conserved receptor-like protein kinase (RPK gene from wheat and other Triticeae species. The TaRPK1 was isolated from the Triticum aestivum cv. Prins - Triticum timopheevii introgression line IGVI-465 carrying the powdery mildew resistance gene Pm6. The TaRPK1 was mapped to homoeologous chromosomes 2A (TaRPK1-2A, 2D (TaRPK1-2D and the Pm6-carrier chromosome 2G (TaRPK1-2G of IGVI-465. Under the tested conditions, only the TaRPK1-2G allele was actively transcribed, producing two distinct transcripts via alternative splicing. The predicted 424-amino acid protein of TaRPK1-2G contained a signal peptide, a transmembrane domain and an intracellular serine/threonine kinase domain, but lacked a typical extracellular domain. The expression of TaRPK1-2G gene was up-regulated upon the infection by Blumeria graminis f.sp. tritici (Bgt and treatment with methyl jasmonate (MeJA, but down-regulated in response to treatments of SA and ABA. Over-expression of TaRPK1-2G in the powdery mildew susceptible wheat variety Prins by a transient expression assay showed that it slightly reduced the haustorium index of the infected Bgt. These data indicated that TaRPK1-2G participated in the defense response to Bgt infection and in the JA signaling pathway. Phylogenetic analysis indicated that TaRPK1-2G was highly conserved among plant species, and the amino acid sequence similarity of TaRPK1-2G among grass species was more than 86%. Based on its conservation, the RPK gene-based STS primers were designed, and used to amplify the RPK orthologs from the homoeologous group-2 chromosomes of all the tested Triticeae species, such as chromosome 2G of T. timopheevii, 2R of Secale cereale, 2H of Hordeum vulgare, 2S of Aegilops speltoides, 2S(l of Ae. longissima, 2M(g of Ae. geniculata, 2S(p and 2U(p of Ae. peregrina. The developed STS markers serve as conserved functional markers for the

  9. Mitochondrial HMG to CoA synthase (mHS): cDNA cloning in human, mouse and C. elegans, mapping to human chromosome 1p12-13 and partial human genomic cloning

    Energy Technology Data Exchange (ETDEWEB)

    Boukaftane, Y.; Robert, M.F.; Mitchell, G.A. [Hopital Sainte-Justine, Montreal, Quebec (Canada)]|[Kingston General Hospital, Ontario (Canada)] [and others

    1994-09-01

    mHS catalyzes the rate-limiting first step of ketogenesis in the liver. A cytoplasmic HS isozyme, encoded by another gene, catalyzes an early step in cholesterol synthesis. Starting from a rat mHS cDNA obtained by RT-PCR from the published rat cDNA sequence, we obtained and sequenced human and mouse cDNAs spanning the entire coding sequence of natural human and mouse mHS, as well as sequencing C. elegans HS-like cDNA. Consensus sequences for 3 mitochondrial and 4 cytoplasmic HSs were created and compared to invertebrate HS sequences. We found high conversation in the active site and at other regions presumably important for HS function. We mapped the mHS locus, HMGCS2 by in situ hybridization to chromosome 1P12-13, in contrast to the human cHS locus (HMGCS1) known to be on chromosome 5p13. Comparative mapping results suggest that these two chromosomal regions may be contiguous in other species, constant with a recent gene duplication event. Furthermore, we have characterized a human genomic mHS subclone containing 4 mHS exons, and found the position of all splice junctions to be identical to that of the hamster cHS gene except for one site in the 3{prime} nontranslated region. We calculate that the mHS and cHS genes were derived from a common ancestor 400-700 Myrs ago, implying that ketogenesis from fat may have become possible around the time of emergence of vertebrates ({approximately}500 Myr ago). Ketogenesis has evolved into an important pathway of energy metabolism, and we predict the mHS deficiency may prove to be responsible for some as yet explained cases of Reye-like syndromes in humans. This hypothesis can now be tested at the molecular level without the necessity of obtaining hepatic tissue.

  10. Artificial synthesis and cloning of human obese gene%人肥胖(obese)基因的人工合成及克隆

    Institute of Scientific and Technical Information of China (English)

    杨林; 吴无畏

    2000-01-01

    根据人肥胖基因的cDNA序列,通过合理的引物设计、链延伸反应、PCR反应以及分子克隆等步骤,成功地合成出编码瘦蛋白(Leptin)的肥胖基因(ob基因)全长片段,并将其克隆至pUC18载体质粒上.序列分析和酶切鉴定显示肥胖基因得到了正确合成和克隆.%According to the known sequence of human ob gene cDNA,the gene coding the leptin was synthesized and cloned into pUC18 vector after reasonable primer designing,DNA strain extending,PCR reaction and molecular cloning.Sequence analysis and RE digest results showed the ob gene was synthesized and cloned correctly.

  11. Toward a molecular cytogenetic map for cultivated sunflower (Helianthus annuus L.) by landed BAC/BIBAC clones.

    Science.gov (United States)

    Feng, Jiuhuan; Liu, Zhao; Cai, Xiwen; Jan, Chao-Chien

    2013-01-01

    Conventional karyotypes and various genetic linkage maps have been established in sunflower (Helianthus annuus L., 2n = 34). However, the relationship between linkage groups and individual chromosomes of sunflower remains unknown and has considerable relevance for the sunflower research community. Recently, a set of linkage group-specific bacterial /binary bacterial artificial chromosome (BAC/BIBAC) clones was identified from two complementary BAC and BIBAC libraries constructed for cultivated sunflower cv. HA89. In the present study, we used these linkage group-specific clones (~100 kb in size) as probes to in situ hybridize to HA89 mitotic chromosomes at metaphase using the BAC-fluorescence in situ hybridization (FISH) technique. Because a characteristic of the sunflower genome is the abundance of repetitive DNA sequences, a high ratio of blocking DNA to probe DNA was applied to hybridization reactions to minimize the background noise. As a result, all sunflower chromosomes were anchored by one or two BAC/BIBAC clones with specific FISH signals. FISH analysis based on tandem repetitive sequences, such as rRNA genes, has been previously reported; however, the BAC-FISH technique developed here using restriction fragment length polymorphism (RFLP)-derived BAC/BIBAC clones as probes to apply genome-wide analysis is new for sunflower. As chromosome-specific cytogenetic markers, the selected BAC/BIBAC clones that encompass the 17 linkage groups provide a valuable tool for identifying sunflower cytogenetic stocks (such as trisomics) and tracking alien chromosomes in interspecific crosses. This work also demonstrates the potential of using a large-insert DNA library for the development of molecular cytogenetic resources.

  12. [Developing a physical map of human chromosome 22 using Pace electrophoresis and large fragment cloning]. Annual report, October 1, 1991--July 1, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Simon, M.I.

    1994-12-31

    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.

  13. An anchored framework BAC map of mouse chromosome 11 assembled using multiplex oligonucleotide hybridization.

    Science.gov (United States)

    Cai, W W; Reneker, J; Chow, C W; Vaishnav, M; Bradley, A

    1998-12-15

    Despite abundant library resources for many organisms, physical mapping of these organisms has been seriously limited due to lack of efficient library screening techniques. We have developed a highly efficient strategy for large-scale screening of genomic libraries based on multiplex oligonucleotide hybridization on high-density genomic filters. We have applied this strategy to generate a bacterial artificial chromosome (BAC) anchored map of mouse chromosome 11. Using the MIT mouse SSLP data, 320 pairs of oligonucleotide probes were designed with an "overgo" computer program that selects new primer sequences that avoid the microsatellite repeat. BACs identified by these probes are automatically anchored to the chromosome. Ninety-two percent of the probes identified positive clones from a 5.9-fold coverage mouse BAC library with an average of 7 positive clones per marker. An average of 4.2 clones was confirmed for 204 markers by PCR. Our data show that a large number of clones can be efficiently isolated from a large genomic library using this strategy with minimal effort. This strategy will have wide application for large-scale mapping and sequencing of human and other large genomes.

  14. DNA Probe Pooling for Rapid Delineation of Chromosomal Breakpoints

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Chun-Mei; Kwan, Johnson; Baumgartner, Adolf; Weier, Jingly F.; Wang, Mei; Escudero, Tomas; Munne' , Santiago; Zitzelsberger, Horst F.; Weier, Heinz-Ulrich

    2009-01-30

    Structural chromosome aberrations are hallmarks of many human genetic diseases. The precise mapping of translocation breakpoints in tumors is important for identification of genes with altered levels of expression, prediction of tumor progression, therapy response, or length of disease-free survival as well as the preparation of probes for detection of tumor cells in peripheral blood. Similarly, in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for carriers of balanced, reciprocal translocations benefit from accurate breakpoint maps in the preparation of patient-specific DNA probes followed by a selection of normal or balanced oocytes or embryos. We expedited the process of breakpoint mapping and preparation of case-specific probes by utilizing physically mapped bacterial artificial chromosome (BAC) clones. Historically, breakpoint mapping is based on the definition of the smallest interval between proximal and distal probes. Thus, many of the DNA probes prepared for multi-clone and multi-color mapping experiments do not generate additional information. Our pooling protocol described here with examples from thyroid cancer research and PGD accelerates the delineation of translocation breakpoints without sacrificing resolution. The turnaround time from clone selection to mapping results using tumor or IVF patient samples can be as short as three to four days.

  15. Identification of a yeast artificial chromosome that spans the human papillary renal cell carcinoma-associated t(X;1) breakpoint in Xp11.2

    NARCIS (Netherlands)

    Suijkerbuijk, R F; Meloni, A M; Sinke, R J; de Leeuw, B; Wilbrink, M; Janssen, H A; Geraghty, M T; Monaco, A P; Sandberg, A A; Geurts van Kessel, A

    1993-01-01

    Recently, a specific chromosome abnormality, t(X;1)(p11;q21), was described for a subgroup of human papillary renal cell carcinomas. The translocation breakpoint in Xp11 is located in the same region as that in t(X;18)(p11;q11)-positive synovial sarcoma. We used fluorescence in situ hybridization (F

  16. Structure, tissue distribution, and chromosomal localization of the prepronociceptin gene.

    Science.gov (United States)

    Mollereau, C; Simons, M J; Soularue, P; Liners, F; Vassart, G; Meunier, J C; Parmentier, M

    1996-08-01

    Nociceptin (orphanin FQ), the newly discovered natural agonist of opioid receptor-like (ORL1) receptor, is a neuropeptide that is endowed with pronociceptive activity in vivo. Nociceptin is derived from a larger precursor, prepronociceptin (PPNOC), whose human, mouse, and rat genes we have now isolated. The PPNOC gene is highly conserved in the three species and displays organizational features that are strikingly similar to those of the genes of preproenkephalin, preprodynorphin, and preproopiomelanocortin, the precursors to endogenous opioid peptides, suggesting the four genes belong to the same family-i.e., have a common evolutionary origin. The PPNOC gene encodes a single copy of nociceptin as well as of other peptides whose sequence is strictly conserved across murine and human species; hence it is likely to be neurophysiologically significant. Northern blot analysis shows that the PPNOC gene is predominantly transcribed in the central nervous system (brain and spinal cord) and, albeit weakly, in the ovary, the sole peripheral organ expressing the gene. By using a radiation hybrid cell line panel, the PPNOC gene was mapped to the short arm of human chromosome 8 (8p21), between sequence-tagged site markers WI-5833 and WI-1172, in close proximity of the locus encoding the neurofilament light chain NEFL. Analysis of yeast artificial chromosome clones belonging to the WC8.4 contig covering the 8p21 region did not allow to detect the presence of the gene on these yeast artificial chromosomes, suggesting a gap in the coverage within this contig.

  17. What is Cloning?

    Science.gov (United States)

    Donate Home Cloning What is Cloning What is Cloning Clones are organisms that are exact genetic copies. ... clones made through modern cloning technologies. How Is Cloning Done? Many people first heard of cloning when ...

  18. 亚洲棉5号染色体RGAs克隆与分析%Cloning and Analysis of RGAs from 5th Chromosome in Gossypiumn arboreum

    Institute of Scientific and Technical Information of China (English)

    彭仁海; 程华; 刘方; 王春英; 黎绍惠; 张香娣; 王玉红; 王坤波

    2012-01-01

    棉花是最主要的天然纤维作物,深入进行棉花基因组研究具有重要意义.采用酶解、前后低渗和轻压相结合的方法制备亚洲棉染色体中期膜载片,激光法分离亚洲棉第5号单染色体,建单染色体扩增池后克隆其抗病基因同源序列(RGAs),获得P7、P12、P19和P23等4个序列.序列比对和聚类分析表明,这4条序列均为NBS-LRR类RGAs,P7、P12、P19聚成一类,它们之间的同源性很高,P23聚成另一类,与黑松的RPS2和油菜的RGA30同源性较高.为该染色体分子标记开发、基因克隆乃至全序列测定奠定基础.%Cotton is one of the main natural fiber crops. it is important to accumulate basic data in cotton genome research. The high quality metaphase chromosome membrane preparations of G. arboreum were obtained integrated with method of pre-hypotonicity, enzymolysis, post- hypotonicity and squashed with cover slide. A 5th chromosome was microdissected. Amplified production was obtained after the sequential procedures of protein-removing, enzymolysis and linker adaptor PCR (LA-PCR). A verified system was constructed after integrated the method of Southern blotting, SSR primer amplification and fluorescence in situ hybridization (FISH). Four nucleotide sequence P7, P12, P19 and P23 were obtained. The blast results showed that they are NBS-LRR-type resistant gene analog (RGA). Clustering analysis indicated that the sequences of P7, P12, P19 were high homologous and in the same cluster, the P23 was in other cluster and homologous with RPS2 gene of B. nigra and RGA30 gene of B. napus.

  19. ADVANCES IN REPRODUCTIVE TECHNOLOGIES IN CATTLE: FROM ARTIFICIAL INSEMINATION TO CLONING
    AVANCES EN BIOTECNOLOÍA REPRODUCTIVA EN BOVINOS: DE LA INSEMINACIÓN ARTIFICIAL A LA CLONACIÓN

    OpenAIRE

    Bertolini, L.R; Bertolini, Marcelo

    2009-01-01

    The urge for the control of reproductive processes in animals has propelled a great gain in knowledge, also setting off the development of four generations of assisted reproductive technologies (AR T) for humans and animals. The use of assisted reproductive techniques has been of great importance in livestock production. In general terms, the main first three generations of ARTs, including 1) artificial insemination (AI) and gamete and embryo freezing, 2) multiple ovulation and embryo transfe...

  20. Estimation of long-terminal repeat element content in the Helicoverpa zea genome from next generation sequencing of reduced representation bacterial artificial chromosome (BAC) pools

    Science.gov (United States)

    The lepidopteran pest insect, Helicoverpa zea, feeds on cultivated corn and cotton crops in North America where control remains challenging due to evolution of resistance to chemical and transgenic insecticidal toxins, yet few genomic resources are available for this species. A bacterial artificial...

  1. A first generation physical map of the medaka genome in BACs essential for positional cloning and clone-by-clone based genomic sequencing.

    Science.gov (United States)

    Khorasani, Maryam Zadeh; Hennig, Steffen; Imre, Gabriele; Asakawa, Shuichi; Palczewski, Stefanie; Berger, Anja; Hori, Hiroshi; Naruse, Kiyoshi; Mitani, Hiroshi; Shima, Akihiro; Lehrach, Hans; Wittbrodt, Jochen; Kondoh, Hisato; Shimizu, Nobuyoshi; Himmelbauer, Heinz

    2004-07-01

    In order to realize the full potential of the medaka as a model system for developmental biology and genetics, characterized genomic resources need to be established, culminating in the sequence of the medaka genome. To facilitate the map-based cloning of genes underlying induced mutations and to provide templates for clone-based genomic sequencing, we have created a first-generation physical map of the medaka genome in bacterial artificial chromosome (BAC) clones. In particular, we exploited the synteny to the closely related genome of the pufferfish, Takifugu rubripes, by marker content mapping. As a first step, we clustered 103,144 public medaka EST sequences to obtain a set of 21,121 non-redundant sequence entities. Avoiding oversampling of gene-dense regions, 11,254 of EST clusters were successfully matched against the draft sequence of the fugu genome, and 2363 genes were selected for the BAC map project. We designed 35mer oligonucleotide probes from the selected genes and hybridized them against 64,500 BAC clones of strains Cab and Hd-rR, representing 14-fold coverage of the medaka genome. Our data set is further supplemented with 437 results generated from PCR-amplified inserts of medaka cDNA clones and BAC end-fragment markers. Our current, edited, first generation medaka BAC map consists of 902 map segments that cover about 74% of the medaka genome. The map contains 2721 markers. Of these, 2534 are from expressed sequences, equivalent to a non-redundant set of 2328 loci. The 934 markers (724 different) are anchored to the medaka genetic map. Thus, genetic map assignments provide immediate access to underlying clones and contigs, simplifying molecular access to candidate gene regions and their characterization.

  2. Intracellular screen to identify metagenomic clones that induce or inhibit a quorum-sensing biosensor.

    Science.gov (United States)

    Williamson, Lynn L; Borlee, Bradley R; Schloss, Patrick D; Guan, Changhui; Allen, Heather K; Handelsman, Jo

    2005-10-01

    The goal of this study was to design and evaluate a rapid screen to identify metagenomic clones that produce biologically active small molecules. We built metagenomic libraries with DNA from soil on the floodplain of the Tanana River in Alaska. We extracted DNA directly from the soil and cloned it into fosmid and bacterial artificial chromosome vectors, constructing eight metagenomic libraries that contain 53,000 clones with inserts ranging from 1 to 190 kb. To identify clones of interest, we designed a high throughput "intracellular" screen, designated METREX, in which metagenomic DNA is in a host cell containing a biosensor for compounds that induce bacterial quorum sensing. If the metagenomic clone produces a quorum-sensing inducer, the cell produces green fluorescent protein (GFP) and can be identified by fluorescence microscopy or captured by fluorescence-activated cell sorting. Our initial screen identified 11 clones that induce and two that inhibit expression of GFP. The intracellular screen detected quorum-sensing inducers among metagenomic clones that a traditional overlay screen would not. One inducing clone carries a LuxI homologue that directs the synthesis of an N-acyl homoserine lactone quorum-sensing signal molecule. The LuxI homologue has 62% amino acid sequence identity to its closest match in GenBank, AmfI from Pseudomonas fluorescens, and is on a 78-kb insert that contains 67 open reading frames. Another inducing clone carries a gene with homology to homocitrate synthase. Our results demonstrate the power of an intracellular screen to identify functionally active clones and biologically active small molecules in metagenomic libraries.

  3. Cloning, Expression, and Chromosomal Stabilization of the Propionibacterium shermanii Proline Iminopeptidase Gene (pip) for Food-Grade Application in Lactococcus lactis

    Science.gov (United States)

    Leenhouts, Kees; Bolhuis, Albert; Boot, Johan; Deutz, Inge; Toonen, Marjolein; Venema, Gerard; Kok, Jan; Ledeboer, Aat

    1998-01-01

    Proline iminopeptidase produced by Propionibacterium shermanii plays an essential role in the flavor development of Swiss-type cheeses. The enzyme (Pip) was purified and characterized, and the gene (pip) was cloned and expressed in Escherichia coli and Lactococcus lactis, the latter species being an extensively studied, primary cheese starter culture that is less fastidious in its growth condition requirements than P. shermanii. The levels of expression of the pip gene could be enhanced with a factor 3 to 5 by using a strong constitutive promoter in L. lactis or the inducible tac promoter in E. coli. Stable replication of the rolling-circle replicating (rcr) plasmid, used to express pip in L. lactis, could only be obtained by providing the repA gene in trans. Upon the integration of pip, clear gene dosage effects were observed and stable multicopy integrants could be maintained upon growth under the selective pressure of sucrose. The multicopy integrants demonstrated a high degree of stability in the presence of glucose. This study examines the possibilities to overexpress genes that play an important role in food fermentation processes and shows a variety of options to obtain stable food-grade expression of such genes in L. lactis. PMID:9835556

  4. Molecular cloning and chromosomal localization of the human cyclin C (CCNC) and cyclin E (CCNE) genes: Deletion of the CCNC gene in human tumors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Haimin; Lahti, J.M.; Kidd, V.J. [St. Jude Children`s Research Hospital, Memphis, TN (United States)] [and others

    1996-03-01

    The human G1-phase cyclins are important regulators of cell cycle progression that interact with various cyclin-dependent kinases and facilitate entry into S-phase. We have confirmed the localization of the human cyclin C (CCNC) gene to chromosome 6q21 and of human cyclin E (CCNE to 19q12). The CCNC gene structure was also determined, and we have shown that it is deleted in a subset of acute lymphoblastic leukemias, including a patient sample containing a t(2;6)(p21;q15), with no apparent cytogenetic deletion. Single-strand conformational polymorphism analysis of the remaining CCNC allele from patients with a deletion of one allele established that there were no further mutations within the exons or the flanking intronic sequences. These results suggest either that haploinsufficiency of the cyclin C protein is sufficient to promote tumorigenesis or that the important tumor suppressor gene is linked to the CCNC locus. 48 refs., 4 figs., 1 tab.

  5. Cloning of Rabbit HPRT Gene Using the Recombineering System

    Institute of Scientific and Technical Information of China (English)

    Jianjun SHI; Donghui CAI; Xuejin CHEN; Huizheng SHENG

    2007-01-01

    Hypoxanthine phosphoribosyltransferase (HPRT) plays an important role in the metabolic salvage of purines, and been used as an alternative pathway for mutant selection in many studies. To facilitate its application in rabbits, we have cloned the cDNA and genomic DNA of the rabbit HPRT gene using an approach that combines bioinformatics and recombineering methods. The cDNA is comprised of 1449 bp containing a coding sequence for a protein of 218 amino acids. The deduced amino acid sequence of the rabbit HPRT gene shares 98%, 97%, 98% and 94% identity with human, mouse, pig and cattle HPRT genes, respectively. Reverse transcription-polymerase chain reaction analysis showed that this gene is ubiquitously expressed in tissues of adult rabbit. The rabbit HPRT gene spans approximately 48 kb in length and consists of nine exons. The cloning of the rabbit HPRT gene shows the usefulness of the recombineering system in cloning genes of large size. This system may facilitate the subcloning of DNA from bacterial artificial chromosomes for cloning genes of large size or filling big gaps in genomic sequencing.

  6. Molecular cloning of the interleukin-1 gene cluster: Construction of an integrated YAC/PAC contig and a partial transcriptional map in the region of chromosome 2q13

    Energy Technology Data Exchange (ETDEWEB)

    Nothwang, H.G.; Strahm, B.; Denich, D. [Freiburg Univ. (Germany)] [and others

    1997-05-01

    Genes of the interleukin-1 (IL-1) gene cluster localized on chromosome 2q13 are implicated in many physiological and pathophysiological processes. We present here a high-resolution physical map of this region between markers D2S2008 and D2S43/PAX8. An integrated YAC/PAC contig and a partial transcriptional map were constructed by STS-content mapping using the CEPH YAC library and three PAC libraries. A total of 3 YACs, 34 PACs, and 56 STSs were integrated: 33 newly generated probes to PAC end sequences, 9 polymorphic and 4 nonpolymorphic markers, 5 known genes, 4 expressed sequence tags, and 1 pseudogene. Within the map, a complete PAC contig of > 1 Mb encompasses the IL-1 gene cluster and PAX8, a paired-box-containing gene. This allowed us to define the transcriptional orientation of GLVR1, IL1B, and IL1RN and to show that PAX8 is localized outside the IL-1 gene cluster. FISH analysis localized PAC clones containing the IL-1 gene cluster to 2q12-q13. The data provide the basis for further characterization of the IL-1 gene cluster and for the construction of a sequence-ready PAC contig of this region. 45 refs., 2 figs., 2 tabs.

  7. Molecular cloning of a highly conserved mouse and human integral membrane protein (Itm1) and genetic mapping to mouse chromosome 9

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Guizhu; Tylzanowski, P. [Univ. of Antwerp (Belgium); Deleersnijder, W. [N.V. Innogenetics, Ghent (Belgium)] [and others

    1996-02-01

    We have isolated and characterized a novel cDNA coding for a highly hydrophobic protein (B5) from a fetal mouse mandibular condyle cDNA library. The full-length mouse B5 cDNA is 3095 nucleotides long and contains a potential open reading frame coding for a protein of 705 amino acids with a calculated molecular weight of 80.5 kDa. The B5 mRNA is differentially polyadenylated, with the most abundant transcript having a length of 2.7 kb. The human homolog of B5 was isolated from a cDNA testis library. The predicted amino acid sequence of the human B5 is 98.5% identical to that of mouse. The most striking feature of the B5 protein is the presence of numerous (10-14) potential transmembrane domains, characteristic of an integral membrane protein. Similarity searches in public databanks reveal that B5 is 58% similar to the T12A2.2 gene of Caenorhabditis elegans and 60% similar to the STT3 gene of Saccharomyces cerevisiae. Futhermore, the report of an EST sequence (Accession No. Z13858) related to the human B5, but identical to the STT3 gene, indicates that B5 belongs to a larger gene family coding for novel putative transmembrane proteins. This family exhibits a remarkable degree of conservation in different species. The gene for B5, designated Itm1 (Integral membrane protein 1), is located on mouse chromosome 9. 28 refs., 4 figs.

  8. Quantum cloning

    OpenAIRE

    Scarani, Valerio; Iblisdir, Sofyan; Gisin, Nicolas; Acin, Antonio

    2005-01-01

    The impossibility of perfectly copying (or cloning) an arbitrary quantum state is one of the basic rules governing the physics of quantum systems. The processes that perform the optimal approximate cloning have been found in many cases. These "quantum cloning machines" are important tools for studying a wide variety of tasks, e.g. state estimation and eavesdropping on quantum cryptography. This paper provides a comprehensive review of quantum cloning machines (both for discrete-dimensional an...

  9. Whole genome comparison of donor and cloned dogs

    OpenAIRE

    Kim, Hak-Min; Cho, Yun Sung; Kim, Hyunmin; Jho, Sungwoong; Son, Bongjun; Choi, Joung Yoon; Kim, Sangsoo; Lee, Byeong Chun; Bhak, Jong; Jang, Goo

    2013-01-01

    Cloning is a process that produces genetically identical organisms. However, the genomic degree of genetic resemblance in clones needs to be determined. In this report, the genomes of a cloned dog and its donor were compared. Compared with a human monozygotic twin, the genome of the cloned dog showed little difference from the genome of the nuclear donor dog in terms of single nucleotide variations, chromosomal instability, and telomere lengths. These findings suggest that cloning by somatic ...

  10. Marker chromosomes.

    Science.gov (United States)

    Rao, Kiran Prabhaker; Belogolovkin, Victoria

    2013-04-01

    Marker chromosomes are a morphologically heterogeneous group of structurally abnormal chromosomes that pose a significant challenge in prenatal diagnosis. Phenotypes associated with marker chromosomes are highly variable and range from normal to severely abnormal. Clinical outcomes are very difficult to predict when marker chromosomes are detected prenatally. In this review, we outline the classification, etiology, cytogenetic characterization, and clinical consequences of marker chromosomes, as well as practical approaches to prenatal diagnosis and genetic counseling.

  11. Interstitial and terminal deletion of chromosome Y in a male individual with cryptozoospermia.

    Science.gov (United States)

    Duell, T; Mathews, S; Wunderlich, B; Mittermüller, J; Schmetzer, H

    1998-04-01

    A constitutional de-novo deletion of the long arm of the Y chromosome was detected by standard cytogenetic analysis in a 38-year old male who, except for small testes and cryptozoospermia, was phenotypically normal. The deletion was further characterized by fluorescent in-situ hybridization (FISH) and digital image analysis using contigs of overlapping yeast artificial chromosome (YAC) clones, spanning almost the entire Y chromosome. These results showed that the deletion involved a large interstitial segment on the proximal long arm of the Y chromosome (Yq11.1-->Yq11.22) as well as a more distal portion of the Y chromosome, including the entire heterochromatic region (Yq11.23-->qter). The breakpoints as determined by the YAC probes were defined within the published Vergnaud intervals so that region 6B and 6C was mostly retained. However, the AZFc region harbouring the DAZ locus on distal subinterval 6F was lost in the deletion, making the absence of this region the most probable location for the patient's infertility. The data underline the usefulness of FISH as an alternative technique to conventional banding for the refined detection of chromosome Y deletions/rearrangements.

  12. Correlation of chromosome patterns in human leukemic cells with exposure to chemicals and/or radiation. Progress report, July 1992--August 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J.D.

    1993-09-01

    Progress in identification of chromosomal transformations associated with leukemogenesis is described. In particular progress in DNA cloning of chromosomal break points in human cancer patients is described.

  13. Comprehensive cytological characterization of the Gossypium hirsutum genome based on the development of a set of chromosome cytological markers

    Directory of Open Access Journals (Sweden)

    Wenbo Shan

    2016-08-01

    Full Text Available Cotton is the world's most important natural fiber crop. It is also a model system for studying polyploidization, genomic organization, and genome-size variation. Integrating the cytological characterization of cotton with its genetic map will be essential for understanding its genome structure and evolution, as well as for performing further genetic-map based mapping and cloning. In this study, we isolated a complete set of bacterial artificial chromosome clones anchored to each of the 52 chromosome arms of the tetraploid cotton Gossypium hirsutum. Combining these with telomere and centromere markers, we constructed a standard karyotype for the G. hirsutum inbred line TM-1. We dissected the chromosome arm localizations of the 45S and 5S rDNA and suggest a centromere repositioning event in the homoeologous chromosomes AT09 and DT09. By integrating a systematic karyotype analysis with the genetic linkage map, we observed different genome sizes and chromosomal structures between the subgenomes of the tetraploid cotton and those of its diploid ancestors. Using evidence of conserved coding sequences, we suggest that the different evolutionary paths of non-coding retrotransposons account for most of the variation in size between the subgenomes of tetraploid cotton and its diploid ancestors. These results provide insights into the cotton genome and will facilitate further genome studies in G. hirsutum.

  14. EasyClone-MarkerFree

    DEFF Research Database (Denmark)

    Fabre, Mathew Malcolm Jessop; Jakociunas, Tadas; Stovicek, Vratislav

    2016-01-01

    Clone-MarkerFree. The integration of linearized expression cassettes into defined genomic loci is facilitated by CRISPR/Cas9. Cas9 is recruited to the chromosomal location by specific guide RNAs (gRNAs) expressed from a set of gRNA helper vectors. Using our genome engineering vector suite, single and triple insertions are obtained...

  15. Human mitochondrial HMG CoA synthase: Liver cDNA and partial genomic cloning, chromosome mapping to 1p12-p13, and possible role in vertebrate evolution

    Energy Technology Data Exchange (ETDEWEB)

    Boukaftane, Y.; Robert, M.F.; Mitchell, G.A. [Hopital Sainte-Justine, Montreal (Canada)] [and others

    1994-10-01

    Mitochondrial 3-hydroxy-3-methylglutaryl CoA synthase (mHS) is the first enzyme of ketogenesis, whereas the cytoplasmic HS isozyme (cHS) mediates an early step in cholersterol synthesis. We here report the sequence of human and mouse liver mHS cDNAs, the sequence of an HS-like cDNA from Caenorhabditis elegans, the structure of a partial human mHS genomic clone, and the mapping of the human mHS gene to chromosome 1p12-p13. the nucleotide sequence of the human mHS cDNA encodes a mature mHS peptide of 471 residues, with a mean amino acid identity of 66.5% with cHS from mammals and chicken. Comparative analysis of all known mHS and cHS protein and DNA sequences shows a high degree of conservation near the N-terminus that decreases progressively toward the C-terminus and suggests that the two isozymes arose from a common ancestor gene 400-900 million years ago. Comparison of the gene structure of mHS and cHS is also consistant with a recent duplication event. We hypothesize that the physiologic result of the HS gene duplication was the appearance of HS within the mitochondria around the time of emergence of early vertebrates, which linked preexisting pathways of beta oxidation and leucine catabolism and created the HMG CoA pathway of ketogenesis, thus providing a lipid-derived energy source for the vertebrate brain. 56 refs., 4 figs., 2 tabs.

  16. Complete genomic sequence and an infectious BAC clone of feline herpesvirus-1 (FHV-1).

    Science.gov (United States)

    Tai, S H Sheldon; Niikura, Masahiro; Cheng, Hans H; Kruger, John M; Wise, Annabel G; Maes, Roger K

    2010-06-05

    Infection with feline herpesvirus-1 (FHV-1) is a major cause of upper respiratory and ocular diseases in Felidae. We report the first complete genomic sequence of FHV-1, as well as the construction and characterization of a bacterial artificial chromosome (BAC) clone of FHV-1, which contains the entire FHV-1 genome and has the BAC vector inserted at the left end of U(L). Complete genomic sequences were derived from both the FHV-1 BAC clone and purified virion DNA. The FHV-1 genome is 135,797bp in size with an overall G+C content of 45%. A total of 78 open reading frames were predicted, encoding 74 distinct proteins. The gene arrangement is collinear with that of most sequenced varicelloviruses. The virus regenerated from the BAC was very similar to the parental C-27 strain in vitro in terms of plaque morphology and growth characteristics and highly virulent in cats in a preliminary in vivo study.

  17. A BAC clone of MDV strain GX0101 with REV-LTR integration retained its pathogenicity

    Institute of Scientific and Technical Information of China (English)

    SUN AiJun; LAWRENCE Petherbridge; ZHAO YuGuang; LI YanPeng; NAIR Venugopal K; CUI ZhiZhong

    2009-01-01

    The complete genome of Marek's disease virus (MDV) strain GX0101,which was integrated with the LTR sequences of REV,was cloned in Escherichia coli as a bacterial artificial chromosome (BAC).BAC vector sequences were introduced into the US2 locus of the MDV genome by homologous recombination.The viral DNA containing the BAC vector was used to transform Escherichia coli strain of DH10B.Then the recombinant virus was successfully rescued by transfection of the recombinant BAC DNA into primary chicken embryo fibroblast (CEF).This BAC viral clone was named bac-GX0101.When the reconstituted virus was inoculated into 1-day-old birds,visceral tumors could be detected as early as 62 d post infection.There was no difference in growth ability and pathogenicity to birds between the BAC derived virus and its parental virus.The BAC derived virus maintained its oncogenicity and immunosuppressive effects.In conclusion,the complete genome of GX0101 strain was successfully cloned into BAC and the infectious clone was rescued.With the powerful BAC manipulation system,the infectious clone will provide a useful tool for further understanding the functional roles of the inserted REV-LTR sequence in the GX0101 strain of MDV.

  18. SLiCE: a novel bacterial cell extract-based DNA cloning method.

    Science.gov (United States)

    Zhang, Yongwei; Werling, Uwe; Edelmann, Winfried

    2012-04-01

    We describe a novel cloning method termed SLiCE (Seamless Ligation Cloning Extract) that utilizes easy to generate bacterial cell extracts to assemble multiple DNA fragments into recombinant DNA molecules in a single in vitro recombination reaction. SLiCE overcomes the sequence limitations of traditional cloning methods, facilitates seamless cloning by recombining short end homologies (≥15 bp) with or without flanking heterologous sequences and provides an effective strategy for directional subcloning of DNA fragments from Bacteria Artificial Chromosomes (BACs) or other sources. SLiCE is highly cost effective as a number of standard laboratory bacterial strains can serve as sources for SLiCE extract. In addition, the cloning efficiencies and capabilities of these strains can be greatly improved by simple genetic modifications. As an example, we modified the DH10B Escherichia coli strain to express an optimized λ prophage Red recombination system. This strain, termed PPY, facilitates SLiCE with very high efficiencies and demonstrates the versatility of the method.

  19. Research on the Preparation of Bacterial Artificial Chromosome Library Genomic DNA%细菌人工染色体文库基因组DNA制备技术

    Institute of Scientific and Technical Information of China (English)

    陈献伟; 王会; 关伟军; 高剑峰

    2010-01-01

    试验旨在对基因组DNA的制备进行研究,为细菌人工染色体(bacterial artificial charomosome,BAc)文库的构建奠定基础.以豁眼鹅全血为试验材料,提取高质量的基因组DNA,分别采用Hind Ⅲ、EcoR Ⅰ和BamHⅠ3种限制性内切酶对所提基因组DNA进行部分酶切,并利用控制酶切时间、设置不同的Hind Ⅲ酶切浓度梯度对基因组DNA进行部分酶切.结果表明,Hind Ⅲ为最佳限制性内切酶,并得到了最佳酶切用量(40U/μL).该方法所制备的基因组DNA质量较好,可用于BAC文库的构建.

  20. Process for Assembly and Transformation into Saccharomyces cerevisiae of a Synthetic Yeast Artificial Chromosome Containing a Multigene Cassette to Express Enzymes That Enhance Xylose Utilization Designed for an Automated Platform.

    Science.gov (United States)

    Hughes, Stephen R; Cox, Elby J; Bang, Sookie S; Pinkelman, Rebecca J; López-Núñez, Juan Carlos; Saha, Badal C; Qureshi, Nasib; Gibbons, William R; Fry, Michelle R; Moser, Bryan R; Bischoff, Kenneth M; Liu, Siqing; Sterner, David E; Butt, Tauseef R; Riedmuller, Steven B; Jones, Marjorie A; Riaño-Herrera, Néstor M

    2015-12-01

    A yeast artificial chromosome (YAC) containing a multigene cassette for expression of enzymes that enhance xylose utilization (xylose isomerase [XI] and xylulokinase [XKS]) was constructed and transformed into Saccharomyces cerevisiae to demonstrate feasibility as a stable protein expression system in yeast and to design an assembly process suitable for an automated platform. Expression of XI and XKS from the YAC was confirmed by Western blot and PCR analyses. The recombinant and wild-type strains showed similar growth on plates containing hexose sugars, but only recombinant grew on D-xylose and L-arabinose plates. In glucose fermentation, doubling time (4.6 h) and ethanol yield (0.44 g ethanol/g glucose) of recombinant were comparable to wild type (4.9 h and 0.44 g/g). In whole-corn hydrolysate, ethanol yield (0.55 g ethanol/g [glucose + xylose]) and xylose utilization (38%) for recombinant were higher than for wild type (0.47 g/g and 12%). In hydrolysate from spent coffee grounds, yield was 0.46 g ethanol/g (glucose + xylose), and xylose utilization was 93% for recombinant. These results indicate introducing a YAC expressing XI and XKS enhanced xylose utilization without affecting integrity of the host strain, and the process provides a potential platform for automated synthesis of a YAC for expression of multiple optimized genes to improve yeast strains.

  1. A comparative physical map reveals the pattern of chromosomal evolution between the turkey (Meleagris gallopavo and chicken (Gallus gallus genomes

    Directory of Open Access Journals (Sweden)

    Delany Mary E

    2011-09-01

    Full Text Available Abstract Background A robust bacterial artificial chromosome (BAC-based physical map is essential for many aspects of genomics research, including an understanding of chromosome evolution, high-resolution genome mapping, marker-assisted breeding, positional cloning of genes, and quantitative trait analysis. To facilitate turkey genetics research and better understand avian genome evolution, a BAC-based integrated physical, genetic, and comparative map was developed for this important agricultural species. Results The turkey genome physical map was constructed based on 74,013 BAC fingerprints (11.9 × coverage from two independent libraries, and it was integrated with the turkey genetic map and chicken genome sequence using over 41,400 BAC assignments identified by 3,499 overgo hybridization probes along with > 43,000 BAC end sequences. The physical-comparative map consists of 74 BAC contigs, with an average contig size of 13.6 Mb. All but four of the turkey chromosomes were spanned on this map by three or fewer contigs, with 14 chromosomes spanned by a single contig and nine chromosomes spanned by two contigs. This map predicts 20 to 27 major rearrangements distinguishing turkey and chicken chromosomes, despite up to 40 million years of separate evolution between the two species. These data elucidate the chromosomal evolutionary pattern within the Phasianidae that led to the modern turkey and chicken karyotypes. The predominant rearrangement mode involves intra-chromosomal inversions, and there is a clear bias for these to result in centromere locations at or near telomeres in turkey chromosomes, in comparison to interstitial centromeres in the orthologous chicken chromosomes. Conclusion The BAC-based turkey-chicken comparative map provides novel insights into the evolution of avian genomes, a framework for assembly of turkey whole genome shotgun sequencing data, and tools for enhanced genetic improvement of these important agricultural and

  2. Optical mapping of a rice B AC clone using restriction endonuclease and imaging with fluorescent microscopy at single molecule level

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A method of constructing restriction map by optical mapping and single molecule fluorescent microscopy is described. DNA molecules were aligned and adsorbed on a glass coverslip surface by a mbdified "molecular combing"technique, and then the surface-immobilized DNAs were cleaved in situ with a restriction endonuclease. Individual DNA molecules digested by the endonuclease EcoR I were observable with fluorescent microscopy. Using optical mapping, a physical map of a rice bacterial artificial chromosome clone was constructed. This method will facilitate genomic mapping and tracing the dynamic process in real time at a single molecule level with fluorescence microscopy.

  3. Construction and characterization of two Citrus BAC libraries and identification of clones containing the phytoene synthase gene.

    Science.gov (United States)

    Baig, M N R; Yu, An; Guo, Wenwu; Deng, Xiuxin

    2009-05-01

    Two deep-coverage Bacterial Artificial Chromosome (BAC) libraries of Citrus sinensis (L.) Osbeck 'Cara Cara' navel orange and Citrus reticulata (L.) Blanco 'Egan No. 1' Ponkan mandarin, which belong to the two most important species of the Citrus genus, have been constructed and characterized to facilitate gene cloning and to analyze variety-specific genome composition. The C. sinensis BAC library consists of 36 000 clones with negligible false-positive clones and an estimated average insert size of 126 kb covering ~4.5 x 109 bp and thus providing an 11.8-fold coverage of haploid genome equivalents, whereas the C. reticulata library consists of 21 000 clones also with negligible false-positive clones and an estimated average of 120 kb covering ~2.5 x 109 bp representing a 6.6-fold coverage of haploid genome equivalents. Both libraries were evaluated for contamination with high-copy vector, empty pIndigoBAC536 vector, and organellar DNA sequences. Screening has been performed by Southern hybridization of BAC filters, which results in genomics research in the two important species C. sinensis and C. reticulata. Resources, high-density filters, individual clones, and whole libraries are available for public distribution and are accessible at the National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University.

  4. Full-length RecE enhances linear-linear homologous recombination and facilitates direct cloning for bioprospecting.

    Science.gov (United States)

    Fu, Jun; Bian, Xiaoying; Hu, Shengbaio; Wang, Hailong; Huang, Fan; Seibert, Philipp M; Plaza, Alberto; Xia, Liqiu; Müller, Rolf; Stewart, A Francis; Zhang, Youming

    2012-05-01

    Functional analysis of genome sequences requires methods for cloning DNA of interest. However, existing methods, such as library cloning and screening, are too demanding or inefficient for high-throughput application to the wealth of genomic data being delivered by massively parallel sequencing. Here we describe direct DNA cloning based on the discovery that the full-length Rac prophage protein RecE and its partner RecT mediate highly efficient linear-linear homologous recombination mechanistically distinct from conventional recombineering mediated by Redαβ from lambda phage or truncated versions of RecET. We directly cloned all ten megasynthetase gene clusters (each 10–52 kb in length) from Photorhabdus luminescens into expression vectors and expressed two of them in a heterologous host to identify the metabolites luminmycin A and luminmide A/B. We also directly cloned cDNAs and exactly defined segments from bacterial artificial chromosomes. Direct cloning with full-length RecE expands the DNA engineering toolbox and will facilitate bioprospecting for natural products.

  5. Walking, cloning, and mapping with YACs in 3q27: Localization of five ESTs including three members of the cystatin gene family and identification of CpG islands

    Energy Technology Data Exchange (ETDEWEB)

    James, L.A.; Ogilvie, D.J.; Anand, R. [Zeneca Pharmaceuticals, Cheshire (United Kingdom)] [and others

    1996-03-05

    Using yeast artificial chromosomes, we have generated a high-resolution physical map for 2.7 Mb of human chromosomal region 3q27. The YAC clones group into three contigs, one of which has also been linked to the CEPH YAC contig map of human chromosome 3. Fluorescence in situ hybridization has been used to order the contigs on the chromosome and to estimate the distance between them. Expressed sequence tags for five genes, including three members of the cystatin gene family and a gene thought to be involved in B-cell non-Hodgkin lymphoma, have been placed within the YAC contigs, and 12 putative CpG islands have been identified. These YACs provide a useful resource to complete the physical mapping of 3q27 and to begin identification and characterization of further genes that are located there. 27 refs., 1 fig., 1 tab.

  6. Academic Cloning.

    Science.gov (United States)

    Sikula, John P.; Sikula, Andrew F.

    1980-01-01

    The authors define "cloning" as an integral feature of all educational systems, citing teaching practices which reward students for closely reproducing the teacher's thoughts and/or behaviors and administrative systems which tend to promote like-minded subordinates. They insist, however, that "academic cloning" is not a totally…

  7. Construction of the Primary Physical Map of Rice Chromosome 12

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A primary physical map of rice chromosome 12 was constructed using marker-based chromosome landing and chromosome walking. A BAC library from IR64 was screened using 84 RFLP markers, 4 STS markers and 6 microsatellite markers on chromosome 12 by colony hybridization and polymerase chain reaction (PCR) amplification. A total of 59 contigs consisting of 419 BAC clones including 5 single-clones were physically aligned on rice chromosome 12 with the largest BAC contig covering 855 kb. The whole physical map had a size of ~16 Mb and covered about 52% of rice chromosome 12. This physical map will be certainly helpful for map-based gene cloning of agronomically and biological important genes and understanding the genome structure of the chromosome.

  8. Fish on avian lampbrush chromosomes produces higher resolution gene mapping

    NARCIS (Netherlands)

    Galkina, S.A.; Deryusheva, S.; Fillon, V.; Vignal, A.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Rodionov, A.V.; Gaginskaya, E.

    2006-01-01

    Giant lampbrush chromosomes, which are characteristic of the diplotene stage of prophase I during avian oogenesis, represent a very promising system for precise physical gene mapping. We applied 35 chicken BAC and 4 PAC clones to both mitotic metaphase chromosomes and meiotic lampbrush chromosomes o

  9. Consensus maps of cloned plant cuticle genes

    Institute of Scientific and Technical Information of China (English)

    Eviatar; Nevo

    2010-01-01

    Plant cuticle,which covers the plant surface,consists of waxes and cutins,and is associated with plant drought,cold,and salt resistance.Hitherto,at least 47 genes participating in the formation of plant cuticle have been cloned from Arabidopsis thaliana,Oryza sativa,Zea mays,Ricinus communis,Brassica napus,and Medicago truncatula;and about 85% of them encode proteins sharing above 50% identities with their rice homologous sequences.These cloned cuticle genes were mapped in silico on different chromosomes of rice and Arabidopsis,respectively.The mapping results revealed that plant cuticle genes were not evenly distributed in both genomes.About 40% of the mapped cuticle genes were located on chromosome 1 in Arabidopsis,while 20% of the mapped cuticle genes were located on chromosome 2 but none on chromosome 12 in rice.Some cloned plant cuticle genes have several rice homologous sequences,which might be produced by chromosomal segment duplication.The consensus map of cloned plant cuticle genes will provide important clues for the selection of candidate genes in a positional cloning of an unknown cuticle gene in plants.

  10. Nested chromosomal fragmentation in yeast using the meganuclease I-Sce I: a new method for physical mapping of eukaryotic genomes.

    Science.gov (United States)

    Thierry, A; Dujon, B

    1992-11-11

    We have developed a new method for the physical mapping of genomes and the rapid sorting of genomic libraries which is based on chromosome fragmentation by the meganuclease I-Sce I, the first available member of a new class of endonucleases with very long recognition sequences. I-Sce I allows complete cleavage at a single artificially inserted site in an entire genome. Sites can be inserted by homologous recombination using specific cassettes containing selectable markers or, at random, using transposons. This method has been applied to the physical mapping of chromosome XI (620 kb) of Saccharomyces cerevisi and to the sorting of a cosmid library. Our strategy has potential applications to various genome mapping projects. A set of transgenic yeast strains carrying the I-Sce I sites at various locations along a chromosome defines physical intervals against which new genes, DNA fragments or clones can be mapped directly by simple hybridizations.

  11. Human Cloning

    Science.gov (United States)

    2006-07-20

    genes, for example, has led to new treatments developed by the biotechnology industry for diseases such as diabetes and hemophilia. In the context of...or imposed a moratorium. The legislation was opposed by a number of medical organizations, the biotechnology industry and many scientists and was not...cloning by FDA.36 They find little evidence to support FDA’s position that cloned human embryos are “drugs.” However, the biotechnology industry and the

  12. Whole genome comparison of donor and cloned dogs.

    Science.gov (United States)

    Kim, Hak-Min; Cho, Yun Sung; Kim, Hyunmin; Jho, Sungwoong; Son, Bongjun; Choi, Joung Yoon; Kim, Sangsoo; Lee, Byeong Chun; Bhak, Jong; Jang, Goo

    2013-10-21

    Cloning is a process that produces genetically identical organisms. However, the genomic degree of genetic resemblance in clones needs to be determined. In this report, the genomes of a cloned dog and its donor were compared. Compared with a human monozygotic twin, the genome of the cloned dog showed little difference from the genome of the nuclear donor dog in terms of single nucleotide variations, chromosomal instability, and telomere lengths. These findings suggest that cloning by somatic cell nuclear transfer produced an almost identical genome. The whole genome sequence data of donor and cloned dogs can provide a resource for further investigations on epigenetic contributions in phenotypic differences.

  13. Construction and characterization of genomic libraries from specific human chromosomes.

    Science.gov (United States)

    Krumlauf, R; Jeanpierre, M; Young, B D

    1982-05-01

    Highly purified fractions of human chromosomes 21 and 22 were isolated from a suspension of metaphase chromosomes stained with ethidium bromide by using a fluorescence-activated cell sorter (FACS II). Two recombinant DNA libraries, representing chromosomes 21 and 22, were constructed by complete digestion of DNA from these fractions with EcoRI and insertion into the vector lambda gtWES lambda B. Twenty clones selected at random from the chromosome 22 library hybridized to EcoRI-digested human DNA, and five of these clones hybridized to single bands identical in size to the phage inserts. These five single-copy sequences and a clone coding for an 8S RNA isolated by screening the chromosome 22 library for expressed sequences were characterized in detail. Hybridization of all six clones to a panel of sorted chromosomes and hybrid cell lines confirmed the assignment of the sequences to chromosome 22. The sequences were localized to regions of chromosome 22 by hybridization to translocated chromosomes sorted from a cell line having a balanced translocation t(17;22)(p13;q11) and to hybrid cell lines containing the various portions of another translocation t(X;22)(q13;q112). Five clones reside on the long arm of chromosome 22 between q112 and pter, while one clone and an 18S rRNA gene isolated from the chromosome 22 library reside pter and g112. The construction of chromosome-specific libraries by this method has the advantage of being direct and applicable to nearly all human chromosomes and will be important in molecular analysis of human genetic diseases.

  14. Modeling Chromosomes

    Science.gov (United States)

    Robertson, Carol

    2016-01-01

    Learning about chromosomes is standard fare in biology classrooms today. However, students may find it difficult to understand the relationships among the "genome", "chromosomes", "genes", a "gene locus", and "alleles". In the simple activity described in this article, which follows the 5E approach…

  15. Multicolor FISHs for simultaneous detection of genes and DNA segments on human chromosomes.

    Science.gov (United States)

    Shimizu, Nobuyoshi; Maekawa, Masahiko; Asai, Satoko; Shimizu, Yoshiko

    2015-12-01

    We have developed a convenient multicolor fluorescent in situ hybridization (FISH) (five-, four-, three-, and two-color FISHs) for detecting specific genes/DNA segments on the human chromosomes. As a foundation of multicolor FISH, we first isolated 80 bacterial artificial chromosome (BAC) probes that specifically detect the peri-centromeres (peri-CEN) and subtelomeres (subTEL) of 24 different human chromosomes (nos. 1~22, X, and Y) by screening our homemade BAC library (Keio BAC library) consisting of 200,000 clones. Five-color FISH was performed using human DNA segments specific for peri-CEN or subTEL, which were labeled with five different fluorescent dyes [7-diethylaminocoumarin (DEAC): blue, fluorescein isothiocyanate (FITC): green, rhodamine 6G (R6G): yellow, TexRed: red, and cyanine5 (Cy5): purple]. To observe FISH signals under a fluorescence microscope, five optic filters were carefully chosen to avoid overlapping fluorescence emission. Five-color FISH and four-color FISH enabled us to accurately examine the numerical anomaly of human chromosomes. Three-color FISH using two specific BAC clones, that distinguish 5' half of oncogene epidermal growth factor receptor (EGFR) from its 3' half, revealed the amplification and truncation of EGFR in EGFR-overproducing cancer cells. Moreover, two-color FISH readily detected a fusion gene in leukemia cells such as breakpoint cluster region (BCR)/Abelson murine leukemia viral oncogene homologue (ABL) on the Philadelphia (Ph') chromosome with interchromosomal translocation. Some other successful cases such as trisomy 21 of Down syndrome are presented. Potential applications of multicolor FISH will be discussed.

  16. The evolution of chromosomal instability in Chinese hamster cells: a changing picture?

    Science.gov (United States)

    Ponnaiya, B.; Limoli, C. L.; Corcoran, J.; Kaplan, M. I.; Hartmann, A.; Morgan, W. F.

    1998-01-01

    PURPOSE: To investigate the kinetics of chromosomal instability induced in clones of Chinese hamster cells following X-irradiation. MATERIALS AND METHODS: X-irradiated clones of GM10115, human-hamster hybrid cells containing a single human chromosome 4 (HC4), have been previously established. These clones were defined as unstable if they contained > or = three subpopulations of cells with unique rearrangements of HC4 as detected by FISH. Stable and unstable clones were analysed by FISH and Giemsa staining at various times post-irradiation. RESULTS: While most of the stable clones continued to show chromosomal stability of HC4 over time, one became marginally unstable at approximately 45 population doublings post-irradiation. Clones exhibiting chromosomal instability had one of several fates. Many of the unstable clones were showed similar levels of instability over time. However, one unstable clone became stable with time in culture, while another became even more unstable over time. Cytogenetic analyses of all clones after Giemsa staining indicated that in some clones the hamster chromosomes were rearranged independent of HC4, demonstrating increased frequencies of chromatid breaks and dicentric chromosomes. The majority of the unstable clones also had higher yields of chromatid gaps. CONCLUSIONS: These data demonstrate the dynamic nature of chromosomal instability as measured by two different cytogenetic assays.

  17. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  18. Physical Mapping and Refinement of the Painted Turtle Genome (Chrysemys picta) Inform Amniote Genome Evolution and Challenge Turtle-Bird Chromosomal Conservation.

    Science.gov (United States)

    Badenhorst, Daleen; Hillier, LaDeana W; Literman, Robert; Montiel, Eugenia Elisabet; Radhakrishnan, Srihari; Shen, Yingjia; Minx, Patrick; Janes, Daniel E; Warren, Wesley C; Edwards, Scott V; Valenzuela, Nicole

    2015-06-24

    Comparative genomics continues illuminating amniote genome evolution, but for many lineages our understanding remains incomplete. Here, we refine the assembly (CPI 3.0.3 NCBI AHGY00000000.2) and develop a cytogenetic map of the painted turtle (Chrysemys picta-CPI) genome, the first in turtles and in vertebrates with temperature-dependent sex determination. A comparison of turtle genomes with those of chicken, selected nonavian reptiles, and human revealed shared and novel genomic features, such as numerous chromosomal rearrangements. The largest conserved syntenic blocks between birds and turtles exist in four macrochromosomes, whereas rearrangements were evident in these and other chromosomes, disproving that turtles and birds retain fully conserved macrochromosomes for greater than 300 Myr. C-banding revealed large heterochromatic blocks in the centromeric region of only few chromosomes. The nucleolar-organizing region (NOR) mapped to a single CPI microchromosome, whereas in some turtles and lizards the NOR maps to nonhomologous sex-chromosomes, thus revealing independent translocations of the NOR in various reptilian lineages. There was no evidence for recent chromosomal fusions as interstitial telomeric-DNA was absent. Some repeat elements (CR1-like, Gypsy) were enriched in the centromeres of five chromosomes, whereas others were widespread in the CPI genome. Bacterial artificial chromosome (BAC) clones were hybridized to 18 of the 25 CPI chromosomes and anchored to a G-banded ideogram. Several CPI sex-determining genes mapped to five chromosomes, and homology was detected between yet other CPI autosomes and the globally nonhomologous sex chromosomes of chicken, other turtles, and squamates, underscoring the independent evolution of vertebrate sex-determining mechanisms.

  19. Diploid clone produces unreduced diploid gametes but tetraploid clone generates reduced diploid gametes in the Misgurnus loach.

    Science.gov (United States)

    Morishima, Kagayaki; Yoshikawa, Hiroyuki; Arai, Katsutoshi

    2012-02-01

    Most individuals of the loach Misgurnus anguillicaudatus reproduce bisexually, but cryptic clonal lineages reproduce by natural gynogenesis of unreduced diploid eggs that are genetically identical to maternal somatic cells. Triploid progeny often occur by the accidental incorporation of a sperm nucleus into diploid eggs. Sex reversal from a genetic female to a physiological male is easily induced in this species by androgen treatment and through environmental influences. Here, we produced clonal tetraploid individuals by two methods: 1) fertilization of diploid eggs from a clonal diploid female with diploid sperm of a hormonally sex-reversed clonal diploid male and 2) artificial inhibition of the release of the second polar body in eggs of clonal diploid females just after initiation of gynogenetic development. There is no genetic difference between the clonal diploid and tetraploid individuals except for the number of chromosome sets or genomes. Clonal tetraploid males never produced unreduced tetraploid sperm, only diploid sperm that were genetically identical to those of a clonal diploid. Likewise, clonal tetraploid females did not form unreduced tetraploid eggs, just diploid eggs. However, the eggs' genotypes were identical to those of the original clone, and almost all the eggs initiated natural gynogenesis. Thus, gametogenesis of the clonal tetraploid loach is controlled by the presence of two chromosome sets to pair, thereby preserving the normal meiotic process, i.e., the formation of bivalents and subsequently two successive divisions.

  20. Molecular cloning.

    Science.gov (United States)

    Lessard, Juliane C

    2013-01-01

    This protocol describes the basic steps involved in conventional plasmid-based cloning. The goals are to insert a DNA fragment of interest into a receiving vector plasmid, transform the plasmid into E. coli, recover the plasmid DNA, and check for correct insertion events.

  1. Evidence for different origin of sex chromosomes in snakes, birds, and mammals and step-wise differentiation of snake sex chromosomes.

    Science.gov (United States)

    Matsubara, Kazumi; Tarui, Hiroshi; Toriba, Michihisa; Yamada, Kazuhiko; Nishida-Umehara, Chizuko; Agata, Kiyokazu; Matsuda, Yoichi

    2006-11-28

    All snake species exhibit genetic sex determination with the ZZ/ZW type of sex chromosomes. To investigate the origin and evolution of snake sex chromosomes, we constructed, by FISH, a cytogenetic map of the Japanese four-striped rat snake (Elaphe quadrivirgata) with 109 cDNA clones. Eleven of the 109 clones were localized to the Z chromosome. All human and chicken homologues of the snake Z-linked genes were located on autosomes, suggesting that the sex chromosomes of snakes, mammals, and birds were all derived from different autosomal pairs of the common ancestor. We mapped the 11 Z-linked genes of E. quadrivirgata to chromosomes of two other species, the Burmese python (Python molurus bivittatus) and the habu (Trimeresurus flavoviridis), to investigate the process of W chromosome differentiation. All and 3 of the 11 clones were localized to both the Z and W chromosomes in P. molurus and E. quadrivirgata, respectively, whereas no cDNA clones were mapped to the W chromosome in T. flavoviridis. Comparative mapping revealed that the sex chromosomes are only slightly differentiated in P. molurus, whereas they are fully differentiated in T. flavoviridis, and E. quadrivirgata is at a transitional stage of sex-chromosome differentiation. The differentiation of sex chromosomes was probably initiated from the distal region on the short arm of the protosex chromosome of the common ancestor, and then deletion and heterochromatization progressed on the sex-specific chromosome from the phylogenetically primitive boids to the more advanced viperids.

  2. Conditionally amplifiable BACs: switching from single-copy to high-copy vectors and genomic clones.

    Science.gov (United States)

    Wild, Jadwiga; Hradecna, Zdenka; Szybalski, Waclaw

    2002-09-01

    The widely used, very-low-copy BAC (bacterial artificial chromosome) vectors are the mainstay of present genomic research. The principal advantage of BACs is the high stability of inserted clones, but an important disadvantage is the low yield of DNA, both for vectors alone and when carrying genomic inserts. We describe here a novel class of single-copy/high-copy (SC/HC) pBAC/oriV vectors that retain all the advantages of low-copy BAC vectors, but are endowed with a conditional and tightly controlled oriV/TrfA amplification system that allows: (1) a yield of ~100 copies of the vector per host cell when conditionally induced with L-arabinose, and (2) analogous DNA amplification (only upon induction and with copy number depending on the insert size) of pBAC/oriV clones carrying >100-kb inserts. Amplifiable clones and libraries facilitate high-throughput DNA sequencing and other applications requiring HC plasmid DNA. To turn on DNA amplification, which is driven by the oriV origin of replication, we used copy-up mutations in the gene trfA whose expression was very tightly controlled by the araC-P(araBAD) promoter/regulator system. This system is inducible by L-arabinose, and could be further regulated by glucose and fucose. Amplification of DNA upon induction with L-arabinose and its modulation by glucose are robust and reliable. Furthermore, we discovered that addition of 0.2% D-glucose to the growth medium helped toward the objective of obtaining a real SC state for all BAC systems, thus enhancing the stability of their maintenance, which became equivalent to cloning into the host chromosome

  3. Artificial Intelligence.

    Science.gov (United States)

    Waltz, David L.

    1982-01-01

    Describes kinds of results achieved by computer programs in artificial intelligence. Topics discussed include heuristic searches, artificial intelligence/psychology, planning program, backward chaining, learning (focusing on Winograd's blocks to explore learning strategies), concept learning, constraint propagation, language understanding…

  4. A new approach for molecular cloning in cyanobacteria: cloning of an anacystis nidulans met gene using a Tn 907-induced mutant

    NARCIS (Netherlands)

    Tandeau de Marsac, N.; Borrias, W.E.; Kuhlemeijer, C.J.; Castets, A.M.; Arkel, G.A. van; Hondel, C.A.M.J.J. van den

    1982-01-01

    A new strategy for molecular cloning in the cyanobacterium Anacystis nidulans R-2 is described. This strategy involved the use of a transposon and was developed for the cloning of a gene encoding methionine biosynthesis. A met::Tn 901 mutant was isolated. Chromosomal DNA fragments were cloned in the

  5. Assembly of eukaryotic algal chromosomes in yeast

    OpenAIRE

    Karas, Bogumil J.; Molparia, Bhuvan; Jablanovic, Jelena; Hermann, Wolfgang J; Lin, Ying-Chi; Dupont, Christopher L.; Tagwerker, Christian; Yonemoto, Isaac T.; Noskov, Vladimir N.; Chuang, Ray-Yuan; Allen, Andrew E; Glass, John I.; Hutchison, Clyde A; Smith, Hamilton O; Venter, J Craig

    2013-01-01

    Background Synthetic genomic approaches offer unique opportunities to use powerful yeast and Escherichia coli genetic systems to assemble and modify chromosome-sized molecules before returning the modified DNA to the target host. For example, the entire 1 Mb Mycoplasma mycoides chromosome can be stably maintained and manipulated in yeast before being transplanted back into recipient cells. We have previously demonstrated that cloning in yeast of large (> ~ 150 kb), high G + C (55%) prokaryoti...

  6. Hominoid chromosomal rearrangements on 17q map to complex regions of segmental duplication

    OpenAIRE

    Cardone, Maria Francesca; Jiang, Zhaoshi; D'Addabbo, Pietro; Archidiacono, Nicoletta; Rocchi, Mariano; Eichler, Evan E.; Ventura, Mario

    2008-01-01

    Background Chromosomal rearrangements, such as translocations and inversions, are recurrent phenomena during evolution, and both of them are involved in reproductive isolation and speciation. To better understand the molecular basis of chromosome rearrangements and their part in karyotype evolution, we have investigated the history of human chromosome 17 by comparative fluorescence in situ hybridization (FISH) and sequence analysis. Results Human bacterial artificial chromosome/p1 artificial ...

  7. Nephropathic cystinosis (CTNS-LSB): construction of a YAC contig comprising the refined critical region on chromosome 17p13.

    Science.gov (United States)

    Peters, U; Senger, G; Rählmann, M; Du Chesne, I; Stec, I; Köhler, M R; Weissenbach, J; Leal, S M; Koch, H G; Deufel, T; Harms, E

    1997-01-01

    A yeast artificial chromosome (YAC) contig was constructed encompassing the entire region on chromosome 17p13 where the autosomal recessive disorder infantile nephropathic cystinosis (MIM 21980, CTNS-LSB) has been genetically mapped. It comprises seven clones ordered by their content of a series of six sequence-tagged sites (STSs). Fluorescence in situ hybridisation (FISH) revealed two chimaeric clones. The order of four polymorphic STSs mapped with the contig was consistent with that of the known genetic map with the exception of markers D17S1583 (AFMb307zg5) and D17S1798 (AFMa202xf5) where a telomeric location of D17S1583 was inferred from the contig; two non-polymorphic STSs were localised within the marker frame-work. From the analysis of recombination events in an unaffected individual as defined by leucocyte cystine levels we support the high-resolution mapping of this region to a small genetic interval and show that it is entirely represented on a single, non-chimaeric YAC clone in the contig.

  8. Synthetic chromosomes.

    Science.gov (United States)

    Schindler, Daniel; Waldminghaus, Torsten

    2015-11-01

    What a living organism looks like and how it works and what are its components-all this is encoded on DNA, the genetic blueprint. Consequently, the way to change an organism is to change its genetic information. Since the first pieces of recombinant DNA have been used to transform cells in the 1970s, this approach has been enormously extended. Bigger and bigger parts of the genetic information have been exchanged or added over the years. Now we are at a point where the construction of entire chromosomes becomes a reachable goal and first examples appear. This development leads to fundamental new questions, for example, about what is possible and desirable to build or what construction rules one needs to follow when building synthetic chromosomes. Here we review the recent progress in the field, discuss current challenges and speculate on the appearance of future synthetic chromosomes.

  9. A System To Generate Chromosomal Mutations in Lactococcus lactis Which Allows Fast Analysis of Targeted Genes

    NARCIS (Netherlands)

    Law, Jean; Buist, Girbe; Haandrikman, Alfred; Kok, Jan; Venema, Gerhardus; Leenhouts, Kees

    1995-01-01

    A system for generating chromosomal insertions in lactococci is described. It is based on the conditional replication of lactococcal pWV01-derived Ori+ RepA- vector pORI19, containing lacZα and the multiple cloning site of pUC19. Chromosomal AluI fragments of Lactococcus lactis were cloned in pORI19

  10. Construction of libraries enriched for sequence repeats and jumping clones, and hybridization selection for region-specific markers

    Energy Technology Data Exchange (ETDEWEB)

    Kandpal, R.P.; Kandpal, G.; Weissman, S.M. (Yale Univ. School of Medicine, New Haven, CT (United States))

    1994-01-04

    The authors describe a simple and rapid method for constructing small-insert genomic libraries highly enriched for dimeric, trimeric, and tetrameric nucleotide repeat motifs. The approach involves use of DNA inserts recovered by PCR amplification of a small-insert sonicated genomic phage library or by a single-primer PCR amplification of Mbo I-digested and adaptor-ligated genomic DNA. The genomic DNA inserts are heat denatured and hybridized to a biotinylated oligonucleotde. The biotinylated hybrids are retained on a Vectrex-avidin matrix and eluted specifically. The eluate is PCR amplified and cloned. More than 90% of the clones in a library enriched for (CA)[sub n] microsatellites with this approach contained clones with inserts containing CA repeats. They have also used this protocol for enrichment of (CAG)[sub n] and (AGAT)[sub n] sequence repeats and for Not I jumping clones. They have used the enriched libraries with an adaptation of the cDNA selection method to enrich for repeat motifs encoded in yeast artificial chromosomes.

  11. [Analysis of chromosome composition in interspecific embryonic stem hybrid cells of mice].

    Science.gov (United States)

    Pristiazhniuk, I E; Matveeva, N M; Grafodatskiĭ, A S; Serdiukova, N A; Serov, O L

    2010-01-01

    Chromosome complements of twenty hybrid clones obtained by fusion of Mus musculus embryonic stem cells (ESC) and M. caroli splenocytes were studied. Using of double-color in situ hybridization with chromosome- and species-specific probes we were able to detect the parental origin for each chromosome in hybrid cells. Based on parental chromosome ratio, all 20 hybrid clones were separated in some different groups: from the group containing practically tetraploid M. musculus genome with single M. caroli chromosomes to hybrids with dominance of M. caroli chromosome homologues. In 8 hybrid cells clones we observed prevalence of chromosomes originated from ESC in ratio from 5:1 to 3:1. Another hybrid cells clones have either equal (1:1, 1:2) ratio of M. musculus to M. caroli chromosomes or with the prevalence of ESC- (2:1) or splenocyte- (1:2) originated parental chromosome homologues. In 3 hybrid cells clones, we observed preferable segregation of ESC-originated pluripotent chromosomes. This phenomenon was found for the first time and it possibly indicates compensation of the epigenetic differences between parental chromosomes of ESC- and splenocyte-origination.

  12. The molecular characterization of maize B chromosome specific AFLPs

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The origin and evolution of B chromosomes could be explained by the specific DNA sequence on them.But the specific sequences known were quite limited. To investigate maize B chromosome sqicific DNA sequeces, maize genomes with and without B chromosomes were analyzed by AFLP. Only 5 markers were found specific to genomes with B chromosomes among about 2000 AFLP markers. Southern hybridization and sequence analysis revealed that only the sequence of M8-2D was a B chromosome specific sequence.This sequence contained the telomeric repeat unit AGGGTTT conserved in plant chromosome telomeres.In addition, the sequence of M8-2D shared low homology to clones from maize chromosome 4 centromere as well. M8-2D were localized to B chromosome centromeric and telomeric regions.

  13. Chromosome Analysis

    Science.gov (United States)

    1998-01-01

    Perceptive Scientific Instruments, Inc., provides the foundation for the Powergene line of chromosome analysis and molecular genetic instrumentation. This product employs image processing technology from NASA's Jet Propulsion Laboratory and image enhancement techniques from Johnson Space Center. Originally developed to send pictures back to earth from space probes, digital imaging techniques have been developed and refined for use in a variety of medical applications, including diagnosis of disease.

  14. Characterization and mapping to human chromosome 8q24.3 of Ly-6-related gene 9804 encoding an apparent homologue of mouse TSA-1.

    Science.gov (United States)

    Shan, X; Bourdeau, A; Rhoton, A; Wells, D E; Cohen, E H; Landgraf, B E; Palfree, R G

    1998-01-01

    The 9804 gene, which encodes a human Ly-6 protein most similar to mouse differentiation Ag TSA-1/Sca-2, has also been called RIG-E. Like mouse TSA-1, it has a broad tissue distribution with varied expression levels in normal human tissues and tumor cell lines. Like some members of the murine Ly-6 family, the 9804 gene is responsive to IFNs, particularly IFN-alpha. Overlapping genomic fragments spanning the 9804 gene (5543 bp) have been isolated and characterized. The gene organization is analogous to that of known mouse Ly-6 genes. The first exon, 2296 bp upstream from exon II, is entirely untranslated. The three coding exons (II, III, and IV) are separated by short introns of 321 and 131 bp, respectively. Primers were developed for specific amplification of 9804 gene fragments. Screening of human-hamster somatic cell hybrids and yeast artificial chromosomes (YACs) indicated that the gene is distal to c-Myc, located in the q arm of human chromosome 8. No positives were detected from the Centre d'Etude du Polymorphisme Humain mega-YAC A or B panels, nor from bacterial artificial chromosome libraries; two positive cosmids (c101F1 and c157F6) were isolated from a human chromosome 8 cosmid library (LA08NC01). Fluorescence in situ hybridization of metaphase spreads of chromosome 8, containing hybrid cell line 706-B6 clone 17 (CL-17) with cosmid c101F1, placed the 9804 gene close to the telomere at 8q24.3. This mapping is significant, since the region shares a homology with a portion of mouse chromosome 15, which extends into band E where Ly-6 genes reside. Moreover, the gene encoding E48, the homologue of mouse Ly-6 molecule ThB, has also been mapped to 8q24.

  15. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei).

    Science.gov (United States)

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  16. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei.

    Directory of Open Access Journals (Sweden)

    Zuzana Majtánová

    Full Text Available Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis. We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA. Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  17. Genetic modification of mammalian genome at chromosome level

    Directory of Open Access Journals (Sweden)

    OLEG L. SEROV

    2000-09-01

    Full Text Available The review is concerned with a progress in genetic modification of a mammalian genome in vitro and in vivo at chromosomal level. Recently three new approaches for the chromosome biotechnology have been developed: Using Cre/loxP-system a researcher is able to produce targeted rearrangements of whole chromosomes or their segments or particular genes within the genome, and therefore to modify the set, position and copy number of the endogenous elements of the genome. Mammalian artificial chromosomes (MACs provide a possibility to introduce into genome relatively large segments of alien chromosome material, either artificially constructed or derived from the genome of different species. Using ES-somatic cell hybrids allows to transfer whole chromosomes or their fragments between different genomes within and between species. Advantages and limitations of these approaches are discussed.

  18. Artificial blood

    Directory of Open Access Journals (Sweden)

    Sarkar Suman

    2008-01-01

    Full Text Available Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  19. Artificial blood.

    Science.gov (United States)

    Sarkar, Suman

    2008-07-01

    Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  20. Statement on Human Cloning

    Science.gov (United States)

    ... for the Advancement of Science Statement on Human Cloning Tweet The American Association for the Advancement of ... for this statement on human cloning. Ban Reproductive Cloning AAAS endorses a legally enforceable ban on efforts ...

  1. The mapping of novel genes to human chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Buenaventura, J.M. [Sarah Lawrence College, Bronxville, NY (United States)

    1994-12-01

    The principle goal of our laboratory is the discovery of new genes on human chromosome 19. One of the strategies to achieve this goal is through the use of cDNA clones known as {open_quotes}expressed sequence tags{close_quotes} (ESTs). ESTs, short segments of sequence from a cDNA clone that correspond to the mRNA, occur as unique regions in the genome and, therefore, can be used as markers for specific positions. In collaboration with researchers from Genethon in France, fifteen cDNA clones from a normalized human infant brain cDNA library were tested and determined to map to chromosome 19. A verification procedure is then followed to confirm assignment to chromosome 19. First, primers for each cDNA clone are developed and then amplified by polymerase chain reaction from genomic DNA. Next, a {sup 32}P-radiolabeled probe is made by polymerase chain reaction for each clone and then hybridized against filters containing an LLNL chromosome 19-specific cosmid library to find putative locations on the chromosome. The location is then verified by running a polymerase chain reactions from the positive cosmids. With the Browser database at LLNL, additional information about the positive cosmids can be found. Through use of the BLAST database at the National Library of Medicine, homologous sequences to the clones can be found. Among the fifteen cDNA clones received from Genethon, all have been amplified by polymerase chain reaction. Three have turned out as repetitive elements in the genome. Ten have been mapped to specific locations on chromosome 19. Putative locations have been found for the remaining two clones and thus verification testing will proceed.

  2. Molecular mapping of chromosomes 17 and X

    Energy Technology Data Exchange (ETDEWEB)

    Barker, D.F.

    1991-01-15

    Progress toward the construction of high density genetic maps of chromosomes 17 and X has been made by isolating and characterizing a relatively large set of polymorphic probes for each chromosome and using these probes to construct genetic maps. We have mapped the same polymorphic probes against a series of chromosome breakpoints on X and 17. The probes could be assigned to over 30 physical intervals on the X chromosome and 7 intervals on 17. In many cases, this process resulted in improved characterization of the relative locations of the breakpoints with respect to each other and the definition of new physical intervals. The strategy for isolation of the polymorphic clones utilized chromosome specific libraries of 1--15 kb segments from each of the two chromosomes. From these libraries, clones were screened for those detecting restriction fragment length polymorphisms. The markers were further characterized, the chromosomal assignments confirmed and in most cases segments of the original probes were subcloned into plasmids to produce probes with improved signal to noise ratios for use in the genetic marker studies. The linkage studies utilize the CEPH reference families and other well-characterized families in our collection which have been used for genetic disease linkage work. Preliminary maps and maps of portions of specific regions of 17 and X are provided. We have nearly completed a map of the 1 megabase Mycoplasma arthritidis genome by applying these techniques to a lambda phage library of its genome. We have found bit mapping to be an efficient means to organize a contiguous set of overlapping clones from a larger genome.

  3. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  4. Artificial urushi.

    Science.gov (United States)

    Kobayashi, S; Uyama, H; Ikeda, R

    2001-11-19

    A new concept for the design and laccase-catalyzed preparation of "artificial urushi" from new urushiol analogues is described. The curing proceeded under mild reaction conditions to produce the very hard cross-linked film (artificial urushi) with a high gloss surface. A new cross-linkable polyphenol was synthesized by oxidative polymerization of cardanol, a phenol derivative from cashew-nut-shell liquid, by enzyme-related catalysts. The polyphenol was readily cured to produce the film (also artificial urushi) showing excellent dynamic viscoelasticity.

  5. A YAC contig of approximately 3 Mb from human chromosome 5q31 [yields] q33

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang; Wang Jabs, E.; Hawkins, A.L.; Griffin, C.A. (John Hopkins School of Medicine, Baltimore, MD (United States)); Wise, C.A.; Lovett, M. (Univ. of Texas Southwestern Medical Center, Dallas, TX (United States)); Le Paslier, D. (CEPH, Paris (France)); Pittler, S.J. (Univ. of South Alabama College of Medicine, Mobile, AL (United States))

    1994-02-01

    The human chromosome 5q31-q33 region contains an interesting cluster of growth factor and receptor genes. In addition, several genetic disease loci have been localized within this region, but have not as yet been isolated as molecular clones. These include those loci involved in autosomal dominant limb-girdle muscular dystrophy, diastrophic dysplasia, Treacher Collins syndrome, and myeloid disorders associated with the 5q-syndrome. A yeast artificial chromosome (YAC) contig of this region would assist in the further localization and isolation of these genes. The authors have used YACs isolated from the Washington University and Centre d'Etude du Polymorphisme Humain YAC libraries, including YACs from the large insert (mega) YAC library to build a contig greater than 3 Mb in size. An STS content strategy coupled with limited walking from YAC ends was used to isolate 22 overlapping YACs with as much as sixfold coverage. A total of 20 STSs, derived from genes, anonymous sequences, and vector Alu-PCR or inverse PCR products, were used to compile this contig. The order of loci, centromere-GRL-D5S207-D5S70-D5S545-D5S546-D5S547-D5S68-D5S548-D5S210-D5S549-D5S686- ADRB2-D5S559-CSF1R-D5S551-RPS14-D5S519-SPARC-telomere, was derived from the overlapping clones. This contig and clones derived from it will be useful substrates in selecting candidate cDNAs for the disease loci in this interval. 45 refs., 1 fig., 2 tabs.

  6. Isolation, characterization, and chromosomal mapping of the human Nkx6.1 gene (NKX6A), a new pancreatic islet homeobox gene

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Hiroshi; Permutt, M.A.; Veile, R. [Washington Univ. School of Medicine, St. Louis, MO (United States)] [and others

    1997-03-01

    Nkx6.1 (gene symbol NKX6A), a new member of the NK homeobox gene family, was recently identified in rodent pancreatic islet 13-cell lines. The pattern of expression suggested that this gene product might be important for control of islet development and/or regulation of insulin biosynthesis. We now report cloning of human NKX6A, characterization of its genomic structure, and its chromosomal localization. The predicted protein of human NKX6A contained 367 amino acids and had 97% identity to the hamster protein. The highly conserved NK decapeptide and homeodomain regions were identical between human and hamster, suggesting functional importance of these domains. The coding region spanned approximately 4.8 kb and was composed of three exons. The gene was localized to four CEPH {open_quotes}B{close_quotes} yeast artificial chromosome clones (914B4, 951G9, 981D6, and 847133), and a nearby polymorphic marker (D4S1538) on chromosome 4 was identified <1270 kb from the gene. Using fluorescence in situ hybridization, we also determined that NKX6A maps to 4q21.2-q22. 11 refs., 2 figs.

  7. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  8. Artificial Limbs

    Science.gov (United States)

    ... diabetes. They may cause you to need an amputation. Traumatic injuries, including from traffic accidents and military combat Cancer Birth defects If you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which is ...

  9. Chromosomal rearrangements in Tourette syndrome

    DEFF Research Database (Denmark)

    Bertelsen, Birgitte; Debes, Nanette Mol; Hjermind, Lena E

    2013-01-01

    Tourette syndrome (TS) is a childhood-onset complex neurobiological disorder characterized by a combination of persistent motor and vocal tics and frequent presence of other neuropsychiatric comorbidities. TS shares the fate of other complex disorders, where the genetic etiology is largely unknown......, and identification of susceptibility genes through linkage and association studies has been complicated due to inherent difficulties such as no clear mode of inheritance, genetic heterogeneity, and apparently incomplete penetrance. Positional cloning through mapping of disease-related chromosome rearrangements has...

  10. Construction of a genetic map of human chromosome 17 by use of chromosome-mediated gene transfer

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Weiming; Gorman, P.A.; Rider, S.H.; Hedge, P.J.; Moore, G.; Prichard, C.; Sheer, D.; Solomon, E. (Imperial Cancer Research Fund, London (England))

    1988-11-01

    The authors used somatic-cell hybrids, containing as their only human genetic contribution part or all of chromosome 17, as donors for chromosome-mediated gene transfer. A total of 54 independent transfectant clones were isolated and analyzed by use of probes or isoenzymes for >20 loci located on chromosome 17. By combining the data from this chromosome-mediated gene transfer transfectant panel, conventional somatic-cell hybrids containing well-defined breaks on chromosome 17, and in situ hybridization they propose the following order for these loci; pter-(TP53-RNP2-D17S1)-(MYH2-MYH1)-D17Z1-CRYB1-(ERBA1-GCSF-NGL)-acute promyelocytic leukemia breakpoint-RNU2-HOX2-(NGFR-COLIAI-MPO)-GAA-UMPH-GHC-TK1-GALK-qter. Using chromosome-mediated gene transfer, they have also regionally localized the random probes D17S6 to D17S19 on chromosome 17.

  11. The Clone Factory

    Science.gov (United States)

    Stoddard, Beryl

    2005-01-01

    Have humans been cloned? Is it possible? Immediate interest is sparked when students are asked these questions. In response to their curiosity, the clone factory activity was developed to help them understand the process of cloning. In this activity, students reenact the cloning process, in a very simplified simulation. After completing the…

  12. Localization of Sry gene on Y chromosome of Muntjac munticus vaginalis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The chromosomes 1, Y1, Y2 of Muntjac munticus vaginalis were isolated by fluorescence activated chromosome sorting and amplified by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR). A primer pair within human Sry HMG box was designed and the Sry gene of the male M. m vaginalis was amplified. The product was cloned and sequenced. The result proved that Sry is located on chromosome Y2, which is the sex-determining chromosome in the male M. m vaginalis.

  13. Cloning of observables

    OpenAIRE

    Ferraro, Alessandro; Galbiati, Matteo; Paris, Matteo G. A.

    2005-01-01

    We introduce the concept of cloning for classes of observables and classify cloning machines for qubit systems according to the number of parameters needed to describe the class under investigation. A no-cloning theorem for observables is derived and the connections between cloning of observables and joint measurements of noncommuting observables are elucidated. Relationships with cloning of states and non-demolition measurements are also analyzed.

  14. Unrepaired DNA damage facilitates elimination of uniparental chromosomes in interspecific hybrid cells.

    Science.gov (United States)

    Wang, Zheng; Yin, Hao; Lv, Lei; Feng, Yingying; Chen, Shaopeng; Liang, Junting; Huang, Yun; Jiang, Xiaohua; Jiang, Hanwei; Bukhari, Ihtisham; Wu, Lijun; Cooke, Howard J; Shi, Qinghua

    2014-01-01

    Elimination of uniparental chromosomes occurs frequently in interspecific hybrid cells. For example, human chromosomes are always eliminated during clone formation when human cells are fused with mouse cells. However, the underlying mechanisms are still elusive. Here, we show that the elimination of human chromosomes in human-mouse hybrid cells is accompanied by continued cell division at the presence of DNA damage on human chromosomes. Deficiency in DNA damage repair on human chromosomes occurs after cell fusion. Furthermore, increasing the level of DNA damage on human chromosomes by irradiation accelerates human chromosome loss in hybrid cells. Our results indicate that the elimination of human chromosomes in human-mouse hybrid cells results from unrepaired DNA damage on human chromosomes. We therefore provide a novel mechanism underlying chromosome instability which may facilitate the understanding of carcinogenesis.

  15. Physical mapping of a large plant genome using global high-information-content-fingerprinting: the distal region of the wheat ancestor Aegilops tauschii chromosome 3DS

    Directory of Open Access Journals (Sweden)

    You Frank M

    2010-06-01

    Full Text Available Abstract 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

  16. A plasmid RK2-based broad-host-range cloning vector useful for transfer of metagenomic libraries to a variety of bacterial species.

    Science.gov (United States)

    Aakvik, Trine; Degnes, Kristin Fløgstad; Dahlsrud, Rannveig; Schmidt, Frank; Dam, Ragnar; Yu, Lihua; Völker, Uwe; Ellingsen, Trond Erling; Valla, Svein

    2009-06-01

    The majority of microorganisms in natural environments are difficult to cultivate, but their genes can be studied via metagenome libraries. To enhance the chances that these genes become expressed we here report the construction of a broad-host-range plasmid vector (pRS44) for fosmid and bacterial artificial chromosome (BAC) cloning. pRS44 can be efficiently transferred to numerous hosts by conjugation. It replicates in such hosts via the plasmid RK2 origin of replication, while in Escherichia coli it replicates via the plasmid F origin. The vector was found to be remarkably stable due to the insertion of an additional stability element (parDE). The copy number of pRS44 is adjustable, allowing for easy modifications of gene expression levels. A fosmid metagenomic library consisting of 20 000 clones and BAC clones with insert sizes up to 200 kb were constructed. The 16S rRNA gene analysis of the fosmid library DNA confirmed that it represents a variety of microbial species. The entire fosmid library and the selected BAC clones were transferred to Pseudomonas fluorescens and Xanthomonas campestris (fosmids only), and heterologous proteins from the fosmid library were confirmed to be expressed in P. fluorescens. To our knowledge no other reported vector system has a comparable potential for functional screening across species barriers.

  17. Engineered human dicentric chromosomes show centromere plasticity.

    Science.gov (United States)

    Higgins, Anne W; Gustashaw, Karen M; Willard, Huntington F

    2005-01-01

    The centromere is essential for the faithful distribution of a cell's genetic material to subsequent generations. Despite intense scrutiny, the precise genetic and epigenetic basis for centromere function is still unknown. Here, we have used engineered dicentric human chromosomes to investigate mammalian centromere structure and function. We describe three classes of dicentric chromosomes isolated in different cell lines: functionally monocentric chromosomes, in which one of the two genetically identical centromeres is consistently inactivated; functionally dicentric chromosomes, in which both centromeres are consistently active; and dicentric chromosomes heterogeneous with respect to centromere activity. A study of serial single cell clones from heterogeneous cell lines revealed that while centromere activity is usually clonal, the centromere state (i.e. functionally monocentric or dicentric) in some lines can switch within a growing population of cells. Because pulsed field gel analysis indicated that the DNA at the centromeres of these chromosomes did not change detectably, this switching of the centromere state is most likely due to epigenetic changes. Inactivation of one of the two active centromeres in a functionally dicentric chromosome was observed in a percentage of cells after treatment with Trichostatin A, an inhibitor of histone deacetylation. This study provides evidence that the activity of human centromeres, while largely stable, can be subject to dynamic change, most likely due to epigenetic modification.

  18. Reproductive Incompatibility Involving Senegalese Aedes aegypti (L) Is Associated with Chromosome Rearrangements

    Science.gov (United States)

    Dickson, Laura B.; Sharakhova, Maria V.; Timoshevskiy, Vladimir A.; Fleming, Karen L.; Caspary, Alex; Sylla, Massamba; Black, William C.

    2016-01-01

    Aedes aegypti, the primary vector of dengue, yellow fever and Zika flaviviruses, consists of at least two subspecies. Aedes aegypti (Aaa) is light in color, has pale scales on the first abdominal tergite, oviposits in artificial containers, and preferentially feeds on humans. Aedes aegypti formosus (Aaf), has a dark cuticle, is restricted to sub-Saharan Africa, has no pale scales on the first abdominal tergite and frequently oviposits in natural containers. Scale patterns correlate with cuticle color in East Africa but not in Senegal, West Africa where black cuticle mosquitoes display a continuum of scaling patterns and breed domestically indoors. An earlier laboratory study did not indicate any pre- or postzygotic barriers to gene flow between Aaa and Aaf in East Africa. However, similar attempts to construct F1 intercross families between Aaa laboratory strains and Senegal Ae. aegypti (SenAae) failed due to poor F1 oviposition and low F2 egg-to-adult survival. Insemination and assortative mating experiments failed to identify prezygotic mating barriers. Backcrosses were performed to test for postzygotic isolation patterns consistent with Haldane’s rule modified for species, like Aedes, that have an autosomal sex determining locus (SDL). Egg-pupal survival was predicted to be low in females mated to hybrid F1 males but average when a male mates with a hybrid F1 female. Survival was in fact significantly reduced when females mated to hybrid males but egg-pupal survival was significantly increased when males were mated to hybrid F1 females. These observations are therefore inconclusive with regards to Haldane’s rule. Basic cytogenetic analyses and Fluorescent In Situ Hybridization (FISH) experiments were performed to compare SenAae strains with the IB12 strain of Aaa that was used for genome sequencing and physical mapping. Some SenAae strains had longer chromosomes than IB12 and significantly different centromeric indices on chromosomes 1 and 3. DAPI staining

  19. Reproductive Incompatibility Involving Senegalese Aedes aegypti (L) Is Associated with Chromosome Rearrangements.

    Science.gov (United States)

    Dickson, Laura B; Sharakhova, Maria V; Timoshevskiy, Vladimir A; Fleming, Karen L; Caspary, Alex; Sylla, Massamba; Black, William C

    2016-04-01

    Aedes aegypti, the primary vector of dengue, yellow fever and Zika flaviviruses, consists of at least two subspecies. Aedes aegypti (Aaa) is light in color, has pale scales on the first abdominal tergite, oviposits in artificial containers, and preferentially feeds on humans. Aedes aegypti formosus (Aaf), has a dark cuticle, is restricted to sub-Saharan Africa, has no pale scales on the first abdominal tergite and frequently oviposits in natural containers. Scale patterns correlate with cuticle color in East Africa but not in Senegal, West Africa where black cuticle mosquitoes display a continuum of scaling patterns and breed domestically indoors. An earlier laboratory study did not indicate any pre- or postzygotic barriers to gene flow between Aaa and Aaf in East Africa. However, similar attempts to construct F1 intercross families between Aaa laboratory strains and Senegal Ae. aegypti (SenAae) failed due to poor F1 oviposition and low F2 egg-to-adult survival. Insemination and assortative mating experiments failed to identify prezygotic mating barriers. Backcrosses were performed to test for postzygotic isolation patterns consistent with Haldane's rule modified for species, like Aedes, that have an autosomal sex determining locus (SDL). Egg-pupal survival was predicted to be low in females mated to hybrid F1 males but average when a male mates with a hybrid F1 female. Survival was in fact significantly reduced when females mated to hybrid males but egg-pupal survival was significantly increased when males were mated to hybrid F1 females. These observations are therefore inconclusive with regards to Haldane's rule. Basic cytogenetic analyses and Fluorescent In Situ Hybridization (FISH) experiments were performed to compare SenAae strains with the IB12 strain of Aaa that was used for genome sequencing and physical mapping. Some SenAae strains had longer chromosomes than IB12 and significantly different centromeric indices on chromosomes 1 and 3. DAPI staining was

  20. Conversion of BAC Clones into Binary BAC (BIBAC) Vectors and Their Delivery into Basidiomycete Fungal Cells Using Agrobacterium tumefaciens

    KAUST Repository

    Ali, Shawkat

    2014-09-19

    The genetic transformation of certain organisms, required for gene function analysis or complementation, is often not very efficient, especially when dealing with large gene constructs or genomic fragments. We have adapted the natural DNA transfer mechanism from the soil pathogenic bacterium Agrobacterium tumefaciens, to deliver intact large DNA constructs to basidiomycete fungi of the genus Ustilago where they stably integrated into their genome. To this end, Bacterial Artificial Chromosome (BAC) clones containing large fungal genomic DNA fragments were converted via a Lambda phage-based recombineering step to Agrobacterium transfer-competent binary vectors (BIBACs) with a Ustilago-specific selection marker. The fungal genomic DNA fragment was subsequently successfully delivered as T-DNA through Agrobacterium-mediated transformation into Ustilago species where an intact copy stably integrated into the genome. By modifying the recombineering vector, this method can theoretically be adapted for many different fungi.

  1. Mapping of metastasis suppressor genes for prostate cancer by microcell-mediated chromosome transfer

    Institute of Scientific and Technical Information of China (English)

    TomohikoICHIKAWA; ShigeruHOSOKI; HiroyoshiSUZUKI; KoichiroAKAKURA; TatsuoIGARASHI; YuzoFURUYA; MitsuoOSHIMURA; CarrieW.RINKER-SCHAEFFER; NaokiNIHEI; JohnT.ISAACS; HaruoITO

    2000-01-01

    Aim: To identify the metastasis suppressor genes for prostate cancer. Methods: A copy of human chromosomes was introduced into the highly metastatic Dunning R-3327 rat prostate cancer cells by the use of microcell-mediated chromosome transfer. Relationships between the size of human chromosomes introduced into microcell hybrid clones and the number of lung metastases produced by the clones were analyzed to determine which part of human chromosomes contained the metastasis suppressor gene (s) for prostate cancer. To determine portions of human chromosomes introduced, G-banding chromosomal analysis, fluorescence in situ hybridization analysis, and polymerase chain reaction analysis were performed. Results: Each of microcell hybrid clones containing human chromosomes 7, 8, 10, 11, 12, or 17 showed decreased ability to metastasize to the lung without any loss of ttmaorigenicity. This demonstrates that these human chromosomes contain metastasis suppressor genes for prostate cancer. Spontaneous deletion of portions of human chromosomes was observed in the human chromosome 7, 10, 11, 12, and 17 studies. In the human chromosome 8 study, irradiated microcell-mediated chromosome transfer was performed to enrich chromosomal ann deletions of human chromosome 8. Molecular and cytogenetic analyses of microcell hybrid clones demonstrated that metastasis suppressor genes on human chromosomes were located on 7q21-22, 7q31.2-32, 8p21-12, 10q11-22, 11p13-11.2, 12p11-q13, 12q24-ter, and 17pter-q23. KAI1 and MKK4/SEKI were identified as metastasis suppressor genes from 11p11.2 and 17p12, respectively. Conclusion: This assay system is useful to identify metastasis suppressor gene (s) for prostate cancer.

  2. Artificial Intelligence

    CERN Document Server

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  3. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containin......Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie...

  4. Mapping of the human dentin matrix acidic phosphoprotein gene (DMP1) to the dentinogenesis imperfecta type II critical region at chromosome 4q21

    Energy Technology Data Exchange (ETDEWEB)

    Aplin, H.M.; Hirst, K.L.; Crosby, A.H.; Dixon, M.J. [Univ. of Manchester (United Kingdom)

    1995-11-20

    Dentinogenesis imperfecta type II (DGI1) is an autosomal dominant disorder of dentin formation, which has been mapped to human chromosome 4q12-q21. The region most likely to contain the DGI1 locus is a 3.2-cM region surrounding the osteopontin (SPP1) locus. Recently, a novel dentin-specific acidic phosphoprotein (dmp1) has been cloned in the rat and mapped to mouse chromosome 5q21. In the current investigation, we have isolated a cosmid containing the human DMP1 gene. The isolation of a short tandem repeat polymorphism at this locus has allowed us to map the DMP1 locus to human chromosome 4q21 and demonstrate that it is tightly linked to DGI1 in two families (Z{sub max} = 11.01, {theta} = 0.001). The creation of a yeast artificial chromosome contig around SPP1 has further allowed us to demonstrate that DMP1 is located within 150 kb of the bone sialoprotein and 490 kb of the SPP1 loci, respectively. DMP1 is therefore a strong candidate for the DGI1 locus. 12 refs., 2 figs., 1 tab.

  5. Construction of 110 cosmid markers and a 4.5-Mb YAC contig on human chromosome 8p12-q11

    Energy Technology Data Exchange (ETDEWEB)

    Kurimasa, Akihiro; Suzuki, Noriyuki; Kumano, Satoshi; Oshimura, Mitsuo [Tottori Univ. (Japan)] [and others

    1995-07-20

    Microcell hybrids containing various regions of human chromosome 8 were formed by microcell-mediated transfer of neo-tagged chromosome 8 into the cells derived from severe combined immunodeficiency (SCID) mouse. Thus, 110 cosmid markers were isolated from SV40-transformed SCID fibroblast cell line (SCVA) containing a p12-q11.1 region of human chromosome 8 and were assigned to eight regions in 8p12-q11.1, using a microcell-hybrid panel. For positional cloning of a human gene that restores the DNA-repair defect in a mouse with SCID on 8p11.1-q11.1 (SCID region), we constructed a yeast artificial chromosome (YAC) contig of about 4.5 Mb. Overlapping YACs were further aligned by restriction mapping, using rare-cutting restriction endonucleases. The cosmids and YAC contig should facilitate isolation of the SCID gene and other genes, such as the Werner syndrome-responsible gene in or near this region. 29 refs., 5 figs.

  6. Construction, Characterization, and Chromosomal Mapping of a Fosmid Library of the White-Cheeked Gibbon (Nomascus leucogenys)

    Institute of Scientific and Technical Information of China (English)

    Liping; Chen; Jianping; Ye; Yan; Liu; Jinghuan; Wang; Weiting; Su; Fengtang; Yang; Wenhui; Nie

    2007-01-01

    Gibbons have experienced extensive karyotype rearrangements during evolution and represent an ideal model for studying the underlying molecular mechanism of evolutionary chromosomal rearrangements. It is anticipated that the cloning and sequence characterization of evolutionary chromosomal breakpoints will provide vital insights into the molecular force that has driven such a radical karyotype reshuffle in gibbons. We constructed and characterized a high-quality fosmid li- brary of the white-cheeked gibbon (Nomascus leucogenys) containing 192,000 non- redundant clones with an average insert size of 38 kb and 2.5-fold genome coverage. By end sequencing of 100 randomly selected fosmid clones, we generated 196 se- quence tags for the library. These end-sequenced fosmid clones were then mapped onto the chromosomes of the white-cheeked gibbon by fluorescence in situ hy- bridization, and no spurious chimeric clone was detected. BLAST search against the human genome showed a good correlation between the number of hit clones and the number of chromosomes, an indication of unbiased chromosomal distribu- tion of the fosmid library. The chromosomal distribution of the mapped clones is also consistent with the BLAST search result against human and white-cheeked gibbon genomes. The fosmid library and the mapped clones will serve as a valu- able resource for further studying gibbons' chromosomal rearrangements and the underlying molecular mechanism as well as for comparative genomic study in the lesser apes.

  7. Construction of BAC-based physical map and analysis of chromosome rearrangement in Chinese hamster ovary cell lines.

    Science.gov (United States)

    Cao, Yihua; Kimura, Shuichi; Itoi, Takayuki; Honda, Kohsuke; Ohtake, Hisao; Omasa, Takeshi

    2012-06-01

    Chinese hamster ovary (CHO) cells have frequently been used in biotechnology for many years as a mammalian host cell platform for cloning and expressing genes of interest. A detailed physical chromosomal map of the CHO DG44 cell line was constructed by fluorescence in situ hybridization (FISH) imaging using randomly selected 303 BAC clones as hybridization probes (BAC-FISH). The two longest chromosomes were completely paired chromosomes; other chromosomes were partly deleted or rearranged. The end sequences of 624 BAC clones, including 287 mapped BAC clones, were analyzed and 1,119 informative BAC end sequences were obtained. Among 303 mapped BAC clones, 185 clones were used for BAC-FISH analysis of CHO K1 chromosomes and 94 clones for primary Chinese hamster lung cells. Based on this constructed physical map and end sequences, the chromosome rearrangements between CHO DG44, CHO K1, and primary Chinese hamster cells were investigated. Among 20 CHO chromosomes, eight were conserved without large rearrangement in CHO DG44, CHO K1, and primary Chinese hamster cells. This result suggested that these chromosomes were stable and essential in CHO cells and supposedly conserved in other CHO cell lines.

  8. MOLECULAR CLONING OF HUMAN NEUROTROPHIN-4 GENE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective Cloning and sequencing of the human neurotrophin-4(hNT-4) gene.Methods With the chromosomal DNA of human blood lymphocytes as template,hNT-4 coding genes were amplified by polymerase chain reaction(PCR) and recombinated into phage vector pGEM-T Easy,which were sequenced by using Sanger's single stranded DNA terminal termination method.Results The sequence of the cloned gene is completely the same as that reported in the literature(GenBank data base,M86528).Conclusion This study successfully cloning and sequenced the gene of mhNT-4,and it would be convenient for us to study the expression of mhNT-4 in eukaryote,and to continue the research on the gene therapy of Alzheimer's disease intensively.This study indicate that the hNT-4 is conservative in different races and individuals.

  9. Cloning the soil metagenome: a strategy for accessing the genetic and functional diversity of uncultured microorganisms.

    Science.gov (United States)

    Rondon, M R; August, P R; Bettermann, A D; Brady, S F; Grossman, T H; Liles, M R; Loiacono, K A; Lynch, B A; MacNeil, I A; Minor, C; Tiong, C L; Gilman, M; Osburne, M S; Clardy, J; Handelsman, J; Goodman, R M

    2000-06-01

    Recent progress in molecular microbial ecology has revealed that traditional culturing methods fail to represent the scope of microbial diversity in nature, since only a small proportion of viable microorganisms in a sample are recovered by culturing techniques. To develop methods to investigate the full extent of microbial diversity, we used a bacterial artificial chromosome (BAC) vector to construct libraries of genomic DNA isolated directly from soil (termed metagenomic libraries). To date, we have constructed two such libraries, which contain more than 1 Gbp of DNA. Phylogenetic analysis of 16S rRNA gene sequences recovered from one of the libraries indicates that the BAC libraries contain DNA from a wide diversity of microbial phyla, including sequences from diverse taxa such as the low-G+C, gram-positive Acidobacterium, Cytophagales, and Proteobacteria. Initial screening of the libraries in Escherichia coli identified several clones that express heterologous genes from the inserts, confirming that the BAC vector can be used to maintain, express, and analyze environmental DNA. The phenotypes expressed by these clones include antibacterial, lipase, amylase, nuclease, and hemolytic activities. Metagenomic libraries are a powerful tool for exploring soil microbial diversity, providing access to the genetic information of uncultured soil microorganisms. Such libraries will be the basis of new initiatives to conduct genomic studies that link phylogenetic and functional information about the microbiota of environments dominated by microorganisms that are refractory to cultivation.

  10. Cross-species bacterial artificial chromosome (BAC) library screening via overgo-based hybridization and BAC-contig mapping of a yield enhancement quantitative trait locus (QTL) yld1.1 in the Malaysian wild rice Oryza rufipogon.

    Science.gov (United States)

    Song, Beng-Kah; Nadarajah, Kalaivani; Romanov, Michael N; Ratnam, Wickneswari

    2005-01-01

    The construction of BAC-contig physical maps is an important step towards a partial or ultimate genome sequence analysis. Here, we describe our initial efforts to apply an overgo approach to screen a BAC library of the Malaysian wild rice species, Oryza rufipogon. Overgo design is based on repetitive element masking and sequence uniqueness, and uses short probes (approximately 40 bp), making this method highly efficient and specific. Pairs of 24-bp oligos that contain an 8-bp overlap were developed from the publicly available genomic sequences of the cultivated rice, O. sativa, to generate 20 overgo probes for a 1-Mb region that encompasses a yield enhancement QTL yld1.1 in O. rufipogon. The advantages of a high similarity in melting temperature, hybridization kinetics and specific activities of overgos further enabled a pooling strategy for library screening by filter hybridization. Two pools of ten overgos each were hybridized to high-density filters representing the O. rufipogon genomic BAC library. These screening tests succeeded in providing 69 PCR-verified positive hits from a total of 23,040 BAC clones of the entire O. rufipogon library. A minimal tilling path of clones was generated to contribute to a fully covered BAC-contig map of the targeted 1-Mb region. The developed protocol for overgo design based on O. sativa sequences as a comparative genomic framework, and the pooled overgo hybridization screening technique are suitable means for high-resolution physical mapping and the identification of BAC candidates for sequencing.

  11. Duplication and loss of chromosome 21 in two children with Down syndrome and acute leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Rogan, P.K.; Close, P.; Gannutz, L. [Pennsylvania State Univ., Hershey, PA (United States)] [and others

    1995-11-06

    Acute leukemia in Down syndrome (DS) is often associated with additional changes in the number of structure of chromosome 21. We present two DS patients whose leukemic karyotypes were associated with changes in chromosome 21 ploidy. Patient 1 developed acute lymphocytic leukemia (type L1); disomy for chromosome 21 was evident in all blast cells examined. Loss of the paternal chromosome in the leukemic clone produced maternal uniparental disomy with isodisomy over a 25-cM interval. The second patient had acute monoblastic leukemia (type M5) with tetrasomy 21 in all leukemic cells. DNA polymorphism analysis showed duplicate paternal chromosomes in the constitutional genotype. The maternal chromosome was subsequently duplicated in the leukemic clone. The distinct inheritance patterns of chromosome 21 in the blast cells of these patients would appear to indicate that leukemogenesis occurred by different genetic mechanisms in each individual. 57 refs., 2 figs., 3 tabs.

  12. Caracterização citogenética, viabilidade de pólen e hibridação artificial em gérbera Chromosome number, pollen viability and gerbera hybridization

    Directory of Open Access Journals (Sweden)

    Raquel DL Cardoso

    2009-03-01

    Full Text Available Este trabalho foi conduzido com o objetivo de confirmar o número de cromossomos em cultivares de Gerbera hybrida Hort., determinar o número de cromossomos em acessos não comerciais de Gerbera sp., avaliar a viabilidade de pólen e a possibilidade de cruzamentos entre cultivares e acessos não comerciais. Foram coletados ápices de raízes e pólen de seis cultivares e de sete acessos não comerciais. O material coletado foi corado com carmim acético a 45%. A contagem dos cromossomos foi realizada em células metafásicas intactas e a estimativa de viabilidade de pólen realizada por meio da contagem do número de grãos de pólen viáveis e não viáveis. A possibilidade de cruzamento entre as cultivares e entre as cultivares e acessos não comerciais foi avaliada por meio da hibridação entre os genitores femininos, cv. Terra Fame e acesso A8, e masculinos, cvs. Cariba e Azteca. Todos os acessos contiveram cinqüenta cromossomos, indicando que a variação morfológica nos capítulos (simples, semidobrado e dobrado não é devida a mutações cromossômicas numéricas ou a poliploidia. A viabilidade do pólen variou de 87,67% a 99,27%. A formação de sementes foi de 4,46% nos cruzamentos entre cultivares, e de 50% entre o A8 e as cultivares. A compatibilidade genômica entre os acessos, a alta viabilidade do pólen e o sucesso na obtenção de sementes entre acessos comercias e não comerciais, revela a possibilidade de produção de híbridos com novas combinações alélicas e transferência de caracteres desejáveis dos acessos não comerciais para os comerciaisThis work was conducted to confirm the chromosomes number of Gerbera hybrida Hort. cultivars, to determine the chromosomes number in the non commercial accessions of Gerbera sp., and to estimate the pollen viability and the possibility of crossings among different accessions. Root-tip and pollen were collected from six cultivars and seven non commercial accessions. The collected

  13. Ethical issues in cloning.

    Science.gov (United States)

    Satris, S

    2000-01-01

    There is great public concern with the ethics of human cloning. This paper briefly examines some of what I identify as pseudo-problems or myths associated with cloning, and some of the more substantial ethical concerns.

  14. The microcell mediated transfer of human chromosome 8 into highly metastatic rat liver cancer cell line C5F

    Institute of Scientific and Technical Information of China (English)

    Hu Liu; Sheng-Long Ye; Jiong Yang; Zhao-You Tang; Yin-Kun Liu; Lun-Xiu Qin; Shuang-Jian Qiu; Rui-Xia Sun

    2003-01-01

    AIM: Our previous research on the surgical samples of primary liver cancer with CGH showed that the loss of human chromosome 8p had correlation with the metastatic phenotype of liver cancer. In order to seek the functional evidence that there could be a metastatsis suppressor gene (s) for liver cancer on human chromosome 8, we tried to transfer normal human chromosome 8 into rat liver cancer cell line C5F, which had high metastatic potential to lung.METHODS: Human chromosome 8 randomly marked with neo gene was introduced into C5F cell line by MMCT and positive microcell hybrids were screened by double selections of G418 and HAT. Single cell isolation cloning was applied to clone microcell hybrids. Finally, STS-PCR and WCP-FISH were used to confirm the introduction.RESULTS: Microcell hybrids resistant to HAT and G418 were obtained and 15 clones were obtained by single-cell isolation cloning. STS-PCR and WCP-FISH proved that human chromosome 8 had been successfully introduced into rat liver cancer cell line C5F. STS-PCR detected a random loss in the chromosome introduced and WCP-FISH found a consistent recombination of the introduced human chromosome with the rat chromosome.CONCLUSION: The successful introduction of human chromosome 8 into highly metastatic rat liver cancer cell line builds the basis for seeking functional evidence of a metastasis suppressor gene for liver cancer harboring on human chromosome 8 and its subsequent cloning.

  15. Artificial ribonucleases.

    Science.gov (United States)

    Morrow, J R

    1994-01-01

    Many inorganic and organic compounds promote the reactions catalyzed by RNase A. Both the transesterification step, where a 2',3'-cyclic phosphate is formed with concomitant cleavage of RNA, and the hydrolysis step, where the 2',3'-cyclic phosphate is converted to a phosphate monoester, may be mimicked with compounds that are readily synthesized in the laboratory. Electrophilic activation of the phosphate ester and charge neutralization are generally important means by which artificial RNases promote phosphate diester displacement reactions. Several artificial RNases operate by a bifunctional general acid/general base mechanism, as does RNase A. Provision of an intramolecular nucleophile appears to be an important pathway for metal complex promoted phosphate diester hydrolysis. In contrast to the successful design of compounds that promote the reactions catalyzed by RNase A, there are no artificial nucleases to date that will cleave the 3' P-O bond of RNA or hydrolyze an oligonucleotide of DNA. Artificial RNases based on both metal complexes and organic compounds have been described. Metal complexes may be particularly effective catalysts for both transesterification and hydrolysis reactions of phosphate diesters. Under physiological conditions (37 degrees C and neutral pH), several metal complexes catalyze the transesterification of RNA. Future work should involve the development of metal complexes which are inert to metal ion release but which maintain open coordination sites for catalytic activity. The design of compounds containing multiple amine or imidazole groups that may demonstrate bifunctional catalysis is a promising route to new artificial RNases. Further design of these compounds and careful placement of catalytic groups may yield new RNase mimics that operate under physiological conditions. The attachment of artificial RNases to recognition agents such as oligodeoxynucleotides to create new sequence-specific endoribonucleases is an exciting field of

  16. Artificial Intelligence.

    Science.gov (United States)

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve.

  17. Construction of a DNA library from chromosome 4 of rice (Oryza sativa) by microdissection

    Institute of Scientific and Technical Information of China (English)

    MAOYINGWEI; SIYUANLIANG; 等

    1998-01-01

    A simple method to create a chromosome-specific DNA librqary of rice,including microdissection,amplification,charterization and cloning,is described.Rice chromosome 4 from a metaphase cell has been isolated and amplified by the Linker Adapter PCR (LA-PCR).The PCR products were labeled as probes with DIG-11-dUTP using the random priming method.Southern blot analysis with rice genomic DNA and specific RFLP markers demonstrated that the PCR products were derived from rice chromosome 4.A large library comprising over 100,000 recombinant plasmid microclones from rice chromosome 4 was constructed.Colony hybridization showed that 58% of the clones contained single or low-copy sequences and 42% contained repetitive sequences.The size of inserts generated by PCR ranged from 140bp to 500bp.This method will facilitate cloning of the specific chromosome DNA markers and important genes of rice.

  18. Artificial blood.

    OpenAIRE

    1983-01-01

    #Blood substitutes have been developed for almost a century. The various type of artificial blood was continuously available on the market. The theme of this report is to identify the best substitute in emergency situation for some patients and science students. The definition of best is given; thus, as the vital part of the report, the comparison between them is described and discussed. Modified hemoglobin, bovine-based hemoglobin and PFCs are three basic types. In terms of the perfor...

  19. Role of SV40 Integration Site at Chromosomal Interval 1q21.1 in Immortalized CRL2504 Cells

    Science.gov (United States)

    Liu, Jinglan; Kaur, Gurpreet; Zhawar, Vikramjit K.; Zimonjic, Drazen B.; Popescu, Nicholas C.; Kandpal, Raj P.; Athwal, Raghbir S.

    2009-01-01

    We have applied a functional gene transfer strategy to demonstrate the importance of viral integration site in cellular immortalization. The large tumor antigen of SV40 is capable of extending the cellular life span by sequestering tumor suppressor proteins pRB and p53 in virus-transformed human cells. Although SV40-LT is essential, it is not sufficient for cellular immortalization, suggesting that additional alterations in cellular genes are required to attain infinite proliferation. We demonstrate here that the disruption of human chromosomal interval at 1q21.1, by SV40 integration, can be an essential step for cellular immortalization. The transfer of a 150Kb bacterial artificial chromosome (BAC) clone, RP364B14, corresponding to viral integration site in CRL2504 cells, reverted their immortal phenotype. Interestingly, the BAC transfer clones of CRL-2504 cells displayed characteristics of either senescence as shown by β-galactosidase activity or apoptosis as revealed by positive staining with M30 cytoDeath antibody. The SV40 integration at 1q21.1, in the vicinity of epidermal differentiation complex genes, resulted in the down-regulation of the filaggrin (FLG) gene that is part of the epidermal differentiation complex. FLG gene expression was restored to its normal levels in BAC transfer senescent and apoptotic clones. Our results suggest that the disruption of native genomic sequence by SV40 may alter expression of genes involved in senescence and apoptosis by modulating chromatin structure. These studies imply that identification of genes located in the vicinity of viral integration sites in human cancers may be helpful in developing new diagnostic and therapeutic strategies. PMID:19789346

  20. Artificial vision.

    Science.gov (United States)

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  1. Undetected sex chromosome aneuploidy by chromosomal microarray.

    Science.gov (United States)

    Markus-Bustani, Keren; Yaron, Yuval; Goldstein, Myriam; Orr-Urtreger, Avi; Ben-Shachar, Shay

    2012-11-01

    We report on a case of a female fetus found to be mosaic for Turner syndrome (45,X) and trisomy X (47,XXX). Chromosomal microarray analysis (CMA) failed to detect the aneuploidy because of a normal average dosage of the X chromosome. This case represents an unusual instance in which CMA may not detect chromosomal aberrations. Such a possibility should be taken into consideration in similar cases where CMA is used in a clinical setting.

  2. Soybean chromosome painting: a strategy for somatic cytogenetics.

    Science.gov (United States)

    Shi, L; Zhu, T; Morgante, M; Rafalski, J A; Keim, P

    1996-01-01

    Cytological identification of soybean mitotic metaphase chromosomes (2n = 40) has been severely limited by their small size and uniform karyomorphology. We have developed fluorescent in situ hybridization (FISH), PCR-primed in situ labelling (PCR-PRINS) procedures, and molecular probes for routine cytological identification and for the physical mapping of soybean somatic chromosomes. Chromosome preparation has been achieved by modifications of previous protocols and through the preparation of root-tip protoplasts prior to chromosome spreading. Initially our probe selection focused on highly repeated DNAs that provide very intense localized hybridization signals. Repetitive gene probes that have proven valuable include the rDNA loci (5S and 45S) which are chromosome specific. We have also developed satellite DNA probes for two different sequence families: the SB92 and the STR120 satellites. Both of these are tandemly arranged at multiple chromosomal loci. By using different cloned examples of each family, we have been able to selectively label unique subsets of soybean chromosomes. Double hybridization with biotin and digoxigenin labeled probes has allowed us to determine the chromosomal overlap between different probes. In addition, we have joined portions of the metaphase chromosome painting patterns with the genetic map by single-copy FISH and PCR-PRINS detection of the RFLP loci G8.15, G17.3, and A199a and A199b. Total genomic DNA in situ hybridization (GISH) patterns were also used to characterize the soybean chromosomes.

  3. A physical map of Brassica oleracea shows complexity of chromosomal changes following recursive paleopolyploidizations

    Directory of Open Access Journals (Sweden)

    Giattina Emily

    2011-09-01

    Full Text Available Abstract Background Evolution of the Brassica species has been recursively affected by polyploidy events, and comparison to their relative, Arabidopsis thaliana, provides means to explore their genomic complexity. Results A genome-wide physical map of a rapid-cycling strain of B. oleracea was constructed by integrating high-information-content fingerprinting (HICF of Bacterial Artificial Chromosome (BAC clones with hybridization to sequence-tagged probes. Using 2907 contigs of two or more BACs, we performed several lines of comparative genomic analysis. Interspecific DNA synteny is much better preserved in euchromatin than heterochromatin, showing the qualitative difference in evolution of these respective genomic domains. About 67% of contigs can be aligned to the Arabidopsis genome, with 96.5% corresponding to euchromatic regions, and 3.5% (shown to contain repetitive sequences to pericentromeric regions. Overgo probe hybridization data showed that contigs aligned to Arabidopsis euchromatin contain ~80% of low-copy-number genes, while genes with high copy number are much more frequently associated with pericentromeric regions. We identified 39 interchromosomal breakpoints during the diversification of B. oleracea and Arabidopsis thaliana, a relatively high level of genomic change since their divergence. Comparison of the B. oleracea physical map with Arabidopsis and other available eudicot genomes showed appreciable 'shadowing' produced by more ancient polyploidies, resulting in a web of relatedness among contigs which increased genomic complexity. Conclusions A high-resolution genetically-anchored physical map sheds light on Brassica genome organization and advances positional cloning of specific genes, and may help to validate genome sequence assembly and alignment to chromosomes. All the physical mapping data is freely shared at a WebFPC site (http://lulu.pgml.uga.edu/fpc/WebAGCoL/brassica/WebFPC/; Temporarily password-protected: account

  4. Quick and clean cloning.

    Science.gov (United States)

    Thieme, Frank; Marillonnet, Sylvestre

    2014-01-01

    Identification of unknown sequences that flank known sequences of interest requires PCR amplification of DNA fragments that contain the junction between the known and unknown flanking sequences. Since amplified products often contain a mixture of specific and nonspecific products, the quick and clean (QC) cloning procedure was developed to clone specific products only. QC cloning is a ligation-independent cloning procedure that relies on the exonuclease activity of T4 DNA polymerase to generate single-stranded extensions at the ends of the vector and insert. A specific feature of QC cloning is the use of vectors that contain a sequence called catching sequence that allows cloning specific products only. QC cloning is performed by a one-pot incubation of insert and vector in the presence of T4 DNA polymerase at room temperature for 10 min followed by direct transformation of the incubation mix in chemo-competent Escherichia coli cells.

  5. [Stable maintenance of dicentric mini-chromosomes in CHL4 mutants in yeast].

    Science.gov (United States)

    Kuprina, N Iu; Krol', E S; Koriabin, M Iu; Bannikov, V M; Kirillov, A V; Zakhar'ev, V M; Larionov, V L

    1993-01-01

    Earlier we have identified the chl4-1 mutation in a screen for yeast mutants with increased loss of chromosome III and circular artificial minichromosome in mitosis. Mutation in the CHL4 gene leads to a 50-100-fold promotion in the rate of chromosome loss per cell division compared to the isogenic wild type strain. Detailed analysis of behaviour of the circular minichromosome marked by the CUP1 gene has shown that minichromosome nondisjunction (2:0 segregation) leading to an increase in the copy number of minichromosome in part of a cell population is the main reason of minichromosome instability in the mutant. The unique peculiarity of chl4-1 mutation is the ability of the strains carrying this mutation to stably maintain circular dicentric minichromosomes without any rearrangement during many generations. (In the wild type strains dicentric minichromosomes are extremely unstable. As a consequence of that there is a strong selection for cells harboring monocentric derivatives in a population of cells derived from a cell containing a dicentric plasmid). Introduction of the second centromere into one of the natural chromosomes (chromosomes II or III) in the chl4-1 mutant leads to the same dramatic consequences as that in the wild type strain (mitotic lag of cells harboring dicentric chromosomes and, as a result of that, selective pressure for cells harboring monocentric derivatives of dicentric chromosome). A genomic clone of CHL4 was isolated by complementation of the chl4-1 mutation. Nucleotide sequence analysis of CHL4 revealed a 1.4-kb open reading frame with a predicted 53-kDa protein sequence. Analyzing the sequence of the CHL4 protein we have found a region meeting the necessary requirements for the helix-turn-helix (HTH) structure. This region of the CHL4 protein has about 40% homology with the repressor of tryptophane operon (TrpR) of E. coli. A strain containing a null allele of CHL4 was viable under standard growth conditions, but had temperature

  6. Genetic stability of pestivirus genomes cloned into BACs

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Reimann, Ilona; Uttenthal, Åse;

    chromosome (BAC) vector “pBeloBAC11”. This BAC vector provides a markedly higher stability of cloned sequences in E. coli compared to plasmids that form the basis for the existing pestivirus cDNA clones. In this study, two of the newly constructed BAC clones were analysed for genetic stability of the cloned...... pestivirus genomes to demonstrate the suitability of the BAC vector for harbouring pestivirus genomes. Two BAC clones, comprising the complete genomes of BDV Gifhorn (pBeloGif3) and CSFV Paderborn (pBeloPader10) were passaged 15 times in E.coli representing at least 360 bacteria generations. From 15th...... passage of the BAC clones, the entire 5’ and 3’ ends of the cloned genomes and parts of the open reading frame were sequenced and compared to the sequences of the parent BAC clones. The sequenced areas represent approximately 20 % of the cloned genome. No mutations were observed after the extensive...

  7. Molecular cloning and functional characterization of avian interleukin-19

    Science.gov (United States)

    The present study describes the cloning and functional characterization of avian interleukin (IL)-19, a cytokine that, in mammals, alters the balance of Th1 and Th2 cells in favor of the Th2 phenotype. The full-length avian IL-19 gene, located on chromosome 26, was amplified from LPS-stimulated chi...

  8. Plasmid cloning vehicle for Haemophilus influenzae and Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, D.; Clayton, N.L.; Setlow, J.K.

    1982-09-01

    A new plasmid cloning vehicle (pDM2) was used to introduce a library of Haemophilus influenzae chromosomal fragments into H. influenzae. Transformants of the higly recombination-defective rec-1 mutant were more likely to contain exclusively recombinant plasmids after exposure to ligated DNA mixtures than was the wild type. pDM2 could replicate in Escherichia coli K-12.

  9. Disruption of Netrin G1 by a balanced chromosome translocation in a girl with Rett syndrome

    DEFF Research Database (Denmark)

    Borg, Isabella; Freude, Kristine; Kübart, Sabine;

    2005-01-01

    hybridisations, utilizing probes derived from breakpoint spanning BACs, detected several aberrant fragments specific for the patient. Sequence analysis of the cloned junction fragment indicated that on chromosome 1 the predominantly brain-expressed Netrin G1 (NTNG1) gene is disrupted, whereas on chromosome 7...

  10. Chromosome Disorder Outreach

    Science.gov (United States)

    ... BLOG Join Us Donate You are not alone. Chromosome Disorder Outreach, Inc. is a non-profit organization, ... Support For all those diagnosed with any rare chromosome disorder. Since 1992, CDO has supported the parents ...

  11. Chromosome painting in plants.

    NARCIS (Netherlands)

    Schubert, I.; Fransz, P.F.; Fuchs, J.; Jong, de J.H.

    2001-01-01

    The current 'state-of-art' as to chromosome painting in plants is reviewed. We define different situations described as painting so far: i) Genomic in situ hybridisation (GISH) with total genomic DNA to distinguish alien chromosomes on the basis of divergent dispersed repeats, ii) 'Chromosomal in si

  12. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric C-b

  13. Cloning of the human heparan sulfate-N-deacetylase/N-sulfotransferase gene from the Treacher Collins syndrome candidate region at 5q32-q33.1

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, J.; Loftus, S.K.; Gladwin, A.J. [Univ. of Manchester (United Kingdom)] [and others

    1995-03-20

    Treacher Collins syndrome is an autosomal dominant disorder of craniofacial development, the features of which include conductive hearing loss and cleft palate. Previous studies have shown that the Treacher Collins syndrome locus is flanked by D5S519 and SPARC, and a yeast artificial chromosome contig encompassing this {open_quotes}critical region{close_quotes} has been completed. In the current investigation a cosmid containing D5S519 has been used to screen a human placental cDNA library. This has resulted in the cloning of the human heparan sulfate-N-deacetylase/N-sulfotransferase gene. Two different mRNA species that have identical protein coding sequences but that differ in the size and sequence of the 3{prime} untranslated regions (3{prime}UTR) have been identified. The smaller species has a 3{prime}UTR of 1035 bp, whereas that of the larger is 4878 bp. 24 refs., 3 figs.

  14. 野化培训大熊猫采食和人为砍伐对拐棍竹无性系种群生物量的影响%Effects of Wildness Training Giant Pandas' Grazing and Artificial Harvesting on Clone Population Biomass of Umbrella Bamboo (Fargesia robusta)

    Institute of Scientific and Technical Information of China (English)

    周世强; 黄金燕; 张亚辉; 李仁贵; 刘巅; 黄炎; 李德生; 张和民

    2012-01-01

    Giant pandas (Ailuropoda melanoleuca) have evolved to be obligate bamboo grazers, and 99% of their diets consist of subalpine bamboo species. The life span of giant pandas are directly related to the life cycle of the bamboo which pandas feed on, so the regeneration of bamboo is directly linked to survival and conservation of giant pandas. The biomass of population and ramet were used to evaluate the impact of panda foraging and artificial harvesting on the sustainability of umbrella bamboo (Fargesia robusta) in Wolong Nature Reserve, China. From 2003 to 2007, the population density, age, and growth characteristics of F. Robusta clone were monitored by the methods of the immobile plot sampling and positioning observation. Three types of plots were located in the reserve: Grazed (bamboo in the wildness training enclosure from July 2003 to September 2004), harvested (bamboo cut in the spring of 2004), and control (no treatments from 2003 to 2007). The simultaneous regressive models of each age-class bamboo and remnant stake biomass in both ways of population and ramet were constructed using the methods of harvest and non-destructive volume estimation. Then the effects of wildness training pandas' grazing and artificial harvesting on the clone population and ramet biomass of F. Robustav/e were analyzed according to the models. Controlling the demographic, morphologic, population biomass and environmental conditions, panda feeding and artificial harvesting resulted in a reduction of bamboo productivity, and influenced the restoration and development of experimental populations from 2005 to 2007. Compared to the bamboo population biomass in the control plots, the value in panda grazed plots was lower (e.g. Bamboo shoot biomass in grazed plots was 57.79% of that in control plots). The ramet biomass of each age-class bamboo was up to the standards of panda feeding, with the exception of 2004 year, and was in capacity of sustainingly providing food resources to pandas

  15. B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.

    Science.gov (United States)

    Yoshida, Kohta; Terai, Yohey; Mizoiri, Shinji; Aibara, Mitsuto; Nishihara, Hidenori; Watanabe, Masakatsu; Kuroiwa, Asato; Hirai, Hirohisa; Hirai, Yuriko; Matsuda, Yoichi; Okada, Norihiro

    2011-08-01

    The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85%) in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb) revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.

  16. B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.

    Directory of Open Access Journals (Sweden)

    Kohta Yoshida

    2011-08-01

    Full Text Available The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85% in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.

  17. Cloning, expression, and chromosome mapping of human galectin-7

    DEFF Research Database (Denmark)

    Madsen, Peder; Rasmussen, H H; Flint, T

    1995-01-01

    comigrated with IEF 17 as determined by two-dimensional (two-dimensional gel electrophoresis) analysis of proteins expressed by transiently transfected COS-1 cells, and bound lactose. Alignment of the amino acid sequences with other members of the family showed that the amino acids central to the beta...

  18. Circular permutation of a synthetic eukaryotic chromosome with the telomerator

    Science.gov (United States)

    Mitchell, Leslie A.; Boeke, Jef D.

    2014-01-01

    Chromosome engineering is a major focus in the fields of systems biology, genetics, synthetic biology, and the functional analysis of genomes. Here, we describe the “telomerator,” a new synthetic biology device for use in Saccharomyces cerevisiae. The telomerator is designed to inducibly convert circular DNA molecules into mitotically stable, linear chromosomes replete with functional telomeres in vivo. The telomerator cassette encodes convergent yeast telomere seed sequences flanking the I-SceI homing endonuclease recognition site in the center of an intron artificially transplanted into the URA3 selectable/counterselectable auxotrophic marker. We show that inducible expression of the homing endonuclease efficiently generates linear molecules, identified by using a simple plate-based screening method. To showcase its functionality and utility, we use the telomerator to circularly permute a synthetic yeast chromosome originally constructed as a circular molecule, synIXR, to generate 51 linear variants. Many of the derived linear chromosomes confer unexpected phenotypic properties. This finding indicates that the telomerator offers a new way to study the effects of gene placement on chromosomes (i.e., telomere proximity). However, that the majority of synIXR linear derivatives support viability highlights inherent tolerance of S. cerevisiae to changes in gene order and overall chromosome structure. The telomerator serves as an important tool to construct artificial linear chromosomes in yeast; the concept can be extended to other eukaryotes. PMID:25378705

  19. Stochasticity or the fatal `imperfection' of cloning

    Indian Academy of Sciences (India)

    Reiner A Veitia

    2005-02-01

    The concept of clone is analysed with the aim of exploring the limits to which a phenotype can be said to be determined geneticaly. First of all, mutations that result from the replication, topological manipulation or lesion of DNA introduce a source of heritable variation in an otherwise identical genetic background. But more important, stochastic effects in many biological processes may superimpose a phenotypic variation which is not encoded in the genome. The source of stochasticity ranges from the random selection of alleles or whole chromosomes to be expressed in small cell populations, to fluctuations in processes such as gene expression, due to limiting amounts of the players involved. The picture emerging is that the term clone is a statistical over-simplification representing a series of individuals having essentially the same genome but capable of exhibiting wide phenotypic variation. Finally, to what extent fluctuations in biological processes, usually thought of as noise, are in fact signal is also discussed.

  20. Mapping genes on human chromosome 20

    Energy Technology Data Exchange (ETDEWEB)

    Keith, T.; Phipps, P.; Serino, K. [Collaborative Research, Inc., Waltham, MA (United States)] [and others

    1994-09-01

    While a substantial number of genes have been physically localized to human chromosome 20, few have been genetically mapped. In the process of developing a genetic linkage map of chromosome 20, we have mapped microsatellite polymorphisms associated with six genes. Three of these had highly informative polymorphisms (greater than 0.70) that were originally identified by other investigators. These include avian sarcoma oncogene homolog (SRC), ribophorin II (RPN2), and phosphoenolpyruvate carboxykinase (PCK1). Polymorphisms associated with two genes were determined following a screen of their DNA sequences in GenBank. These include dinucleotide polymorphisms in introl II of cystatin c (CST3) and in the promoter region of neuroendocrine convertase 2 (NEC2) with heterozygosities of 0.52 and 0.54, respectively. A sixth gene, prodynorphin (PDYN) was mapped following the identification of a dinucleotide repeat polymorphism (heterozygosity of 0.35) in a cosmid subclone from a YAC homologous to the original phage clone. CA-positive cosmid subclones from a YAC for an additional gene, guanine nucleotide binding protein, alpha (GNAS10), have been identified and sequencing is in progress. Similar efforts were utilized to identify a microsatellite polymorphism from a half-YAC cloned by W. Brown and localized by FISH to 20pter. This polymorphism is highly informative, with a heterozygosity of 0.83, and serves to delimit the genetic map of the short arm of this chromosome.

  1. Cloning-free CRISPR

    NARCIS (Netherlands)

    Arbab, Mandana; Srinivasan, Sharanya; Hashimoto, Tatsunori; Geijsen, Niels; Sherwood, Richard I

    2015-01-01

    We present self-cloning CRISPR/Cas9 (scCRISPR), a technology that allows for CRISPR/Cas9-mediated genomic mutation and site-specific knockin transgene creation within several hours by circumventing the need to clone a site-specific single-guide RNA (sgRNA) or knockin homology construct for each targ

  2. Chromosomal instability in meningiomas.

    Science.gov (United States)

    van Tilborg, Angela A G; Al Allak, Bushra; Velthuizen, Sandra C J M; de Vries, Annie; Kros, Johan M; Avezaat, Cees J J; de Klein, Annelies; Beverloo, H Berna; Zwarthoff, Ellen C

    2005-04-01

    Approximately 60% of sporadic meningiomas are caused by inactivation of the NF2 tumor suppressor gene on chromosome 22. No causative gene is known for the remaining 40%. Cytogenetic analysis shows that meningiomas caused by inactivation of the NF2 gene can be divided into tumors that show monosomy 22 as the sole abnormality and tumors with a more complex karyotype. Meningiomas not caused by the NF2 gene usually have a diploid karyotype. Here we report that, besides the clonal chromosomal aberrations, the chromosome numbers in many meningiomas varied from one metaphase spread to the other, a feature that is indicative of chromosomal instability. Unexpectedly and regardless of genotype, a subgroup of tumors was observed with an average number of 44.9 chromosomes and little variation in the number of chromosomes per metaphase spread. In addition, a second subgroup was recognized with a hyperdiploid number of chromosomes (average 48.5) and considerable variation in numbers per metaphase. However, this numerical instability resulted in a clonal karyotype with chromosomal gains and losses in addition to loss of chromosome 22 only in meningiomas caused by inactivation of the NF2 gene. In cultured cells of all tumor groups, bi- and multinucleated cells were seen, as well as anaphase bridges, residual chromatid strings, multiple spindle poles, and unseparated chromatids, suggesting defects in the mitotic apparatus or kinetochore. Thus, we conclude that even a benign and slow-growing tumor like a meningioma displays chromosomal instability.

  3. Acentric chromosome ends are prone to fusion with functional chromosome ends through a homology-directed rearrangement.

    Science.gov (United States)

    Ohno, Yuko; Ogiyama, Yuki; Kubota, Yoshino; Kubo, Takuya; Ishii, Kojiro

    2016-01-08

    The centromeres of many eukaryotic chromosomes are established epigenetically on potentially variable tandem repeats; hence, these chromosomes are at risk of being acentric. We reported previously that artificially created acentric chromosomes in the fission yeast Schizosaccharomyces pombe can be rescued by end-to-end fusion with functional chromosomes. Here, we show that most acentric/functional chromosome fusion events in S. pombe cells harbouring an acentric chromosome I differed from the non-homologous end-joining-mediated rearrangements that result in deleterious dicentric fusions in normal cells, and were elicited by a previously unidentified homologous recombination (HR) event between chromosome end-associated sequences. The subtelomere repeats associated with the non-fusogenic ends were also destabilized in the surviving cells, suggesting a causal link between general subtelomere destabilization and acentric/functional chromosome fusion. A mutational analysis indicated that a non-canonical HR pathway was involved in the rearrangement. These findings are indicative of a latent mechanism that conditionally induces general subtelomere instability, presumably in the face of accidental centromere loss events, resulting in rescue of the fatal acentric chromosomes by interchromosomal HR.

  4. Measurement of background translocation frequencies in individuals with clones

    Energy Technology Data Exchange (ETDEWEB)

    Wade, M.J.

    1996-08-01

    In the leukemia case the unseparated B and T lymphocytes had a high translocation frequency even after 0.0014, respectively. After purging all clones from the data, the translocation frequencies for Bio 8 and Bio 23 were 0.00750.0014 and 0.0073 metaphases were scored for chromosomal aberrations,, specifically reciprocal translocations, using fluorescence in situ hybridization (FISH). Metaphase spreads were used from two healthy, unexposed individuals (not exposed to radiation, chemotherapy or radiotherapy) and one early B- precursor acute lymphocytic leukemia (ALL) patient (metaphase spreads from both separated T lymphocytes and unseparated B and T lymphocytes were scored). All three individuals had an abnormally high translocation frequency. The high translocation frequencies resulted from clonal expansion of specific translocated chromosomes. I show in this thesis that by purging (discounting or removing) clones from the data of unexposed individuals, one can obtain true background translocation frequencies. In two cases, Bio 8 and Bio 23, the measured translocation frequency for chromosomes 1, 2 and 4 was 0.0124 purging all of the clones from the data. This high translocation frequency may be due to a low frequency of some clones and may not be recognized. The separated T lymphocytes had a higher translocation frequency than expected.

  5. Artificial Economy

    Directory of Open Access Journals (Sweden)

    Alexandru JIVAN

    2011-08-01

    Full Text Available This paper proposes to eliminate, a routine in the economic thinking, claimed to be responsible for the negative essence of economic developments, from the point of view, of the ecological implications (employment in the planetary ecosystem. The methodological foundations start from the natural origins of the functionality of the human economic society according to the originary physiocrat liberalism, and from specific natural characteristics of the humankind. This paper begins with a comment-analysis of the difference between natural and artificial within the economy, and then explains some of the most serious diversions from the natural essence of economic liberalism. It shall be explained the original (heterodox interpretation of the Classical political economy (economics, by making calls to the Romanian economic thinking from aggravating past century. Highlighting the destructive impact of the economy - which, under the invoked doctrines, we call unnatural - allows an intuitive presentation of a logical extension of Marshall's market price, based on previous research. Besides the doctrinal arguments presented, the economic realities inventoried along the way (major deficiencies and effects, determined demonstrate the validity of the hypothesis of the unnatural character and therefore necessarily to be corrected, of the concept and of the mechanisms of the current economy.The results of this paper consist of original heterodox methodspresented, intuitive or developed that can be found conclusively within the key proposals for education and regulation.

  6. Molecular mapping of chromosomes 17 and X. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Barker, D.F.

    1991-01-15

    Progress toward the construction of high density genetic maps of chromosomes 17 and X has been made by isolating and characterizing a relatively large set of polymorphic probes for each chromosome and using these probes to construct genetic maps. We have mapped the same polymorphic probes against a series of chromosome breakpoints on X and 17. The probes could be assigned to over 30 physical intervals on the X chromosome and 7 intervals on 17. In many cases, this process resulted in improved characterization of the relative locations of the breakpoints with respect to each other and the definition of new physical intervals. The strategy for isolation of the polymorphic clones utilized chromosome specific libraries of 1--15 kb segments from each of the two chromosomes. From these libraries, clones were screened for those detecting restriction fragment length polymorphisms. The markers were further characterized, the chromosomal assignments confirmed and in most cases segments of the original probes were subcloned into plasmids to produce probes with improved signal to noise ratios for use in the genetic marker studies. The linkage studies utilize the CEPH reference families and other well-characterized families in our collection which have been used for genetic disease linkage work. Preliminary maps and maps of portions of specific regions of 17 and X are provided. We have nearly completed a map of the 1 megabase Mycoplasma arthritidis genome by applying these techniques to a lambda phage library of its genome. We have found bit mapping to be an efficient means to organize a contiguous set of overlapping@ clones from a larger genome.

  7. The Precarious Prokaryotic Chromosome

    OpenAIRE

    Kuzminov, Andrei

    2014-01-01

    Evolutionary selection for optimal genome preservation, replication, and expression should yield similar chromosome organizations in any type of cells. And yet, the chromosome organization is surprisingly different between eukaryotes and prokaryotes. The nuclear versus cytoplasmic accommodation of genetic material accounts for the distinct eukaryotic and prokaryotic modes of genome evolution, but it falls short of explaining the differences in the chromosome organization. I propose that the t...

  8. Mechanisms for chromosome segregation.

    Science.gov (United States)

    Bouet, Jean-Yves; Stouf, Mathieu; Lebailly, Elise; Cornet, François

    2014-12-01

    Bacteria face the problem of segregating their gigantic chromosomes without a segregation period restricted in time and space, as Eukaryotes do. Segregation thus involves multiple activities, general or specific of a chromosome region and differentially controlled. Recent advances show that these various mechanisms conform to a “pair and release” rule, which appears as a general rule in DNA segregation. We describe the latest advances in segregation of bacterial chromosomes with emphasis on the different pair and release mechanisms.

  9. An integrated molecular cytogenetic map of Cucumis sativus L. chromosome 2

    Directory of Open Access Journals (Sweden)

    Huang Sanwen

    2011-01-01

    Full Text Available Abstract Background Integration of molecular, genetic and cytological maps is still a challenge for most plant species. Recent progress in molecular and cytogenetic studies created a basis for developing integrated maps in cucumber (Cucumis sativus L.. Results In this study, eleven fosmid clones and three plasmids containing 45S rDNA, the centromeric satellite repeat Type III and the pericentriomeric repeat CsRP1 sequences respectively were hybridized to cucumber metaphase chromosomes to assign their cytological location on chromosome 2. Moreover, an integrated molecular cytogenetic map of cucumber chromosomes 2 was constructed by fluorescence in situ hybridization (FISH mapping of 11 fosmid clones together with the cucumber centromere-specific Type III sequence on meiotic pachytene chromosomes. The cytogenetic map was fully integrated with genetic linkage map since each fosmid clone was anchored by a genetically mapped simple sequence repeat marker (SSR. The relationship between the genetic and physical distances along chromosome was analyzed. Conclusions Recombination was not evenly distributed along the physical length of chromosome 2. Suppression of recombination was found in centromeric and pericentromeric regions. Our results also indicated that the molecular markers composing the linkage map for chromosome 2 provided excellent coverage of the chromosome.

  10. Bacterial chromosome segregation.

    Science.gov (United States)

    Possoz, Christophe; Junier, Ivan; Espeli, Olivier

    2012-01-01

    Dividing cells have mechanisms to ensure that their genomes are faithfully segregated into daughter cells. In bacteria, the description of these mechanisms has been considerably improved in the recent years. This review focuses on the different aspects of bacterial chromosome segregation that can be understood thanks to the studies performed with model organisms: Escherichia coli, Bacillus subtilis, Caulobacter crescentus and Vibrio cholerae. We describe the global positionning of the nucleoid in the cell and the specific localization and dynamics of different chromosomal loci, kinetic and biophysic aspects of chromosome segregation are presented. Finally, a presentation of the key proteins involved in the chromosome segregation is made.

  11. Chromosome oscillations in mitosis

    Science.gov (United States)

    Campas, Otger

    2008-03-01

    Successful cell division necessitates a tight regulation of chromosome movement via the activity of molecular motors. Many of the key players at the origin of the forces generating the motion have been identified, but their spatial and temporal organization remains elusive. In animal cells, chromosomes periodically switch between phases of movement towards and away from the pole. This characteristic oscillatory behaviour cannot be explained by the current models of chromosome positioning and congression. We perform a self-contained theoretical analysis in which the motion of mono-oriented chromosomes results from the competition between the activity of the kinetochore and chromokinesin motors on the chromosome arms. Our analysis, consistent with the available experimental data, proposes that the interplay between the aster-like morphology of the spindle and the collective kinetics of molecular motors is at the origin of chromosome oscillations, positioning and congression. It provides a natural explanation for the so-called chromosome directional instability and for the mechanism by which chromosomes sense their position in space. In addition, we estimate the in vivo velocity of chromokinesins at vanishing load and propose new experiments to assess the mechanism at the origin of chromosome movement in cell division.

  12. Characterization of a chromosome-specific chimpanzee alpha satellite subset: Evolutionary relationship to subsets on human chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, P.E.; Gosden, J.; Lawson, D. [Western General Hospital, Edinburgh (United Kingdom)] [and others

    1996-04-15

    Alpha satellite DNA is a tandemly repeated DNA family found at the centromeres of all primate chromosomes examined. The fundamental repeat units of alpha satellite DNA are diverged 169- to 172-bp monomers, often found to be organized in chromosome-specific higher-order repeat units. The chromosomes of human (Homo sapiens (HSA)), chimpanzee (Pan troglodytes (PTR) and Pan paniscus), and gorilla (Gorilla gorilla) share a remarkable similarity and synteny. It is of interest to ask if alpha satellite arrays at centromeres of homologous chromosomes between these species are closely related (evolving in an orthologous manner) or if the evolutionary processes that homogenize and spread these arrays within and between chromosomes result in nonorthologous evolution of arrays. By using PCR primers specific for human chromosome 17-specific alpha satellite DNA, we have amplified, cloned, and characterized a chromosome-specific subset from the PTR chimpanzee genome. Hybridization both on Southern blots and in situ as well as sequence analysis show that this subset is most closely related, as expected, to sequences on HSA 17. However, in situ hybridization reveals that this subset is not found on the homologous chromosome in chimpanzee (PTR 19), but instead on PTR 12, which is homologous to HSA 2p. 40 refs., 3 figs.

  13. Molecular mapping of chromosomes 17 and X

    Energy Technology Data Exchange (ETDEWEB)

    Barker, D.F.

    1989-01-01

    The basic aims of this project are the construction of high density genetic maps of chromosomes 17 and X and the utilization of these maps for the subsequent isolation of a set of physically overlapping DNA segment clones. The strategy depends on the utilization of chromosome specific libraries of small (1--15 kb) segments from each of the two chromosomes. Since the time of submission of our previous progress report, we have refined the genetic map of markers which we had previously isolated for chromosome 17. We have completed our genetic mapping in CEPH reference and NF1 families of 15 markers in the pericentric region of chromosome 17. Physical mapping results with three probes, were shown be in very close genetic proximity to the NF1 gene, with respect to two translocation breakpoints which disrupt the activity of the gene. All three of the probes were found to lie between the centromere and the most proximal translocation breakpoint, providing important genetic markers proximal to the NF1 gene. Our primary focus has shifted to the X chromosome. We have isolated an additional 30 polymorphic markers, bringing the total number we have isolated to over 80. We have invested substantial effort in characterizing the polymorphisms at each of these loci and constructed plasmid subclones which reveal the polymorphisms for nearly all of the loci. These subclones are of practical value in that they produce simpler and stronger patterns on human genomic Southern blots, thus improving the efficiency of the genetic mapping experiments. These subclones may also be of value for deriving DNA sequence information at each locus, necessary for establishing polymerase chain reaction primers specific for each locus. Such information would allow the use of each locus as a sequence tagged site.

  14. Chromosomal localization of 5S rDNA in Chinese shrimp (Fenneropenaeus chinensis):a chromosome-specific marker for chromosome identification

    Institute of Scientific and Technical Information of China (English)

    郇聘; 张晓军; 李富花; 赵翠; 张成松; 相建海

    2010-01-01

    Chinese shrimp(Fenneropenaeus chinensis)is an economically important aquaculture species in China.However,cytogenetic and genomic data is limited in the organism partly because the chromosomes are difficult to isolate and analyze.In this study,fluorescence in-situ hybridization(FISH) was used to identify the chromosomes of F.chinensis.The 5S ribosomal RNA gene(rDNA)of F. chinensis was isolated,cloned and then used as a hybridization probe.The results show that the 5S rDNA was located on one pair of homologo...

  15. Unified Approach to Universal Cloning and Phase-Covariant Cloning

    OpenAIRE

    Hu, Jia-Zhong; Yu, Zong-Wen; Wang, Xiang-Bin

    2008-01-01

    We analyze the problem of approximate quantum cloning when the quantum state is between two latitudes on the Bloch's sphere. We present an analytical formula for the optimized 1-to-2 cloning. The formula unifies the universal quantum cloning (UQCM) and the phase covariant quantum cloning.

  16. Enzyme free cloning for high throughput gene cloning and expression

    NARCIS (Netherlands)

    de Jong, R.N.; Daniëls, M.; Kaptein, R.; Folkers, G.E.

    2006-01-01

    Structural and functional genomics initiatives significantly improved cloning methods over the past few years. Although recombinational cloning is highly efficient, its costs urged us to search for an alternative high throughput (HTP) cloning method. We implemented a modified Enzyme Free Cloning (EF

  17. Banding studies of chromosomes in a patient with mycosis fungoides

    Energy Technology Data Exchange (ETDEWEB)

    Fukuhara, S.; Rowley, J.D.; Variakojis, D.

    1978-11-01

    Chromosomes from a patient with mycosis fungoides were examined in detail with banding techniques. Hyperdiploid cells from a lymph node had common anomalies of certain chromosomes which formed three similar clones. The abnormalities involved chromosomes Nos. 1, 2, 5, 8, 9, 10, 14, and 18, in addition to an unknown small metacentric marker (M3). Although there were a number of mitotic cells in peripheral blood cultured both with and without PHA, none of the few cells with abnormal karyotypes was similar to the clonal cells of the lymph node. One of the abnormalities in the lymph node was a 14q rearrangement, which could be the result of a translocation of Nos. 8 and 14 involving a third chromosome, No. 2. An abnormality in the blood resulted from a translocation between the long arms of Nos. 1 and 14. These findings could be useful for studies in which mycosis fungoides is compared with the Sezary syndrome and other lymphoid malignancies.

  18. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J

    1983-01-01

    The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...... to women having amniocentesis, although considered not to have any increased risk of fetal chromosome abnormality (1390 pregnancies, group B). They were also compared with 750 consecutive pregnancies in women 25-34 years of age, in whom all heritable diseases were excluded (group C). The risk of unbalanced...... with women without elevated risk. Spontaneous abortion rate and prematurity rate did not differ from rates expected without amniocentesis. It is concluded that current indications may be characterized as a mixture of evident high risk factors and factors with only a minor influence on risk. Indications...

  19. Do Managers Clone Themselves?

    Science.gov (United States)

    Baron, Alma S.

    1981-01-01

    A recent questionnaire survey provides statistics on male managers' views of female managers. The author recommends that male managers break out of their cloning behavior and that the goal ought to be a plurality in management. (Author/WD)

  20. Main: Clone Detail [KOME

    Lifescience Database Archive (English)

    Full Text Available Clone Detail Mapping Pseudomolecule data detail Detail information Mapping to the TIGR japonica Pseudomolecu...les kome_mapping_pseudomolecule_data_detail.zip kome_mapping_pseudomolecule_data_detail ...

  1. BIOETHICS AND HUMAN CLONING

    Directory of Open Access Journals (Sweden)

    Željko Kaluđerović

    2011-12-01

    Full Text Available In this paper the authors analyze the process of negotiating and beginning of the United Nations Declaration on Human Cloning as well as the paragraphs of the very Declaration. The negotiation was originally conceived as a clear bioethical debate that should have led to a general agreement to ban human cloning. However, more often it had been discussed about human rights, cultural, civil and religious differences between people and about priorities in case of eventual conflicts between different value systems. In the end, a non-binding Declaration on Human Cloning had been adopted, full of numerous compromises and ambiguous formulations, that relativized the original intention of proposer states. According to authors, it would have been better if bioethical discussion and eventual regulations on cloning mentioned in the following text had been left over to certain professional bodies, and only after the public had been fully informed about it should relevant supranational organizations have taken that into consideration.

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

    Directory of Open Access Journals (Sweden)

    Wu Cheng-Cang

    2011-05-01

    Full Text Available Background Although second generation sequencing (2GS technologies allow re-sequencing of previously gold-standard-sequenced genomes, 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 still a prerequisite for whole genome sequencing for genomes like barley. To start such an endeavor, large insert genomic libraries, i.e. Bacterial Artificial Chromosome (BAC libraries, which are unbiased and representing deep haploid genome coverage, need to be ready in place. Result Five new BAC libraries were constructed for barley (Hordeum vulgare L. cultivar Morex. These libraries were constructed in different cloning sites (HindIII, EcoRI, MboI and BstXI of the respective vectors. In order to enhance unbiased genome representation and to minimize the number of gaps between BAC contigs, which are often due to uneven distribution of restriction sites, a mechanically sheared library was also generated. The new BAC libraries were fully characterized in depth by scrutinizing the major quality parameters such as average insert size, degree of contamination (plate wide, neighboring, and chloroplast, empty wells and off-scale clones (clones with 250 fragments. Additionally a set of gene-based probes were hybridized to high density BAC filters and showed that genome coverage of each library is between 2.4 and 6.6 X. Conclusion BAC libraries representing >20 haploid genomes are available as a new resource to the barley research community. Systematic utilization of these libraries in high-throughput BAC fingerprinting should allow developing a genome-wide physical map for the barley genome, which will be instrumental for map-based gene isolation and genome sequencing.

  3. Frequent occurrence of highly expanded but unrelated B-cell clones in patients with multiple myeloma.

    Science.gov (United States)

    Kriangkum, Jitra; Motz, Sarah N; Debes Marun, Carina S; Lafarge, Sandrine T; Gibson, Spencer B; Venner, Christopher P; Johnston, James B; Belch, Andrew R; Pilarski, Linda M

    2013-01-01

    Clonal diversity in multiple myeloma (MM) includes both MM-related and MM-unrelated clonal expansions which are subject to dominance exerted by the MM clone. Here we show evidence for the existence of minor but highly expanded unrelated B-cell clones in patients with MM defined by their complementary determining region 3 (CDR3) peak. We further characterize these clones over the disease and subsequent treatment. Second clones were identified by their specific IgH-VDJ sequences that are distinct from those of dominant MM clones. Clonal frequencies were determined through semi-quantitative PCR, quantitative PCR and single-cell polymerase chain reaction of the clone-specific sequence. In 13/74 MM patients, more than one dominant CDR3 peak was identified with 12 patients (16%) being truly biclonal. Second clones had different frequencies, were found in different locations and were found in different cell types from the dominant MM clone. Where analysis was possible, they were shown to have chromosomal characteristic distinct from those of the MM clone. The frequency of the second clone also changed over the course of the disease and often persisted despite treatment. Molecularly-defined second clones are infrequent in monoclonal gammopathy of undetermined significance (MGUS, 1/43 individuals or 2%), suggesting that they may arise at relatively late stages of myelomagenesis. In further support of our findings, biclonal gammopathy and concomitant MM and CLL (chronic lymphocytic leukemia) were confirmed to originate from two unrelated clones. Our data supports the idea that the clone giving rise to symptomatic myeloma exerts clonal dominance to prevent expansion of other clones. MM and second clones may arise from an underlying niche permissive of clonal expansion. The clinical significance of these highly expanded but unrelated clones remains to be confirmed. Overall, our findings add new dimensions to evaluating related and unrelated clonal expansions in MM and the

  4. Frequent occurrence of highly expanded but unrelated B-cell clones in patients with multiple myeloma.

    Directory of Open Access Journals (Sweden)

    Jitra Kriangkum

    Full Text Available Clonal diversity in multiple myeloma (MM includes both MM-related and MM-unrelated clonal expansions which are subject to dominance exerted by the MM clone. Here we show evidence for the existence of minor but highly expanded unrelated B-cell clones in patients with MM defined by their complementary determining region 3 (CDR3 peak. We further characterize these clones over the disease and subsequent treatment. Second clones were identified by their specific IgH-VDJ sequences that are distinct from those of dominant MM clones. Clonal frequencies were determined through semi-quantitative PCR, quantitative PCR and single-cell polymerase chain reaction of the clone-specific sequence. In 13/74 MM patients, more than one dominant CDR3 peak was identified with 12 patients (16% being truly biclonal. Second clones had different frequencies, were found in different locations and were found in different cell types from the dominant MM clone. Where analysis was possible, they were shown to have chromosomal characteristic distinct from those of the MM clone. The frequency of the second clone also changed over the course of the disease and often persisted despite treatment. Molecularly-defined second clones are infrequent in monoclonal gammopathy of undetermined significance (MGUS, 1/43 individuals or 2%, suggesting that they may arise at relatively late stages of myelomagenesis. In further support of our findings, biclonal gammopathy and concomitant MM and CLL (chronic lymphocytic leukemia were confirmed to originate from two unrelated clones. Our data supports the idea that the clone giving rise to symptomatic myeloma exerts clonal dominance to prevent expansion of other clones. MM and second clones may arise from an underlying niche permissive of clonal expansion. The clinical significance of these highly expanded but unrelated clones remains to be confirmed. Overall, our findings add new dimensions to evaluating related and unrelated clonal expansions in

  5. Zebrafish Cx35: cloning and characterization of a gap junction gene highly expressed in the retina.

    Science.gov (United States)

    McLachlan, Elizabeth; White, Thomas W; Ugonabo, Chioma; Olson, Carl; Nagy, James I; Valdimarsson, Gunnar

    2003-09-15

    The vertebrate connexin gene family encodes protein subunits of gap junction channels, which provide a route for direct intercellular communication. Consequently, gap junctions play a vital role in many developmental and homeostatic processes. Aberrant functioning of gap junctions is implicated in many human diseases. Zebrafish are an ideal vertebrate model to study development of the visual system as they produce transparent embryos that develop rapidly, thereby facilitating morphological and behavioral testing. In this study, zebrafish connexin35 has been cloned from a P1 artificial chromosome (PAC) library. Sequence analysis shows a high degree of similarity to the Cx35/36 orthologous group, which are expressed primarily in nervous tissue, including the retina. The gene encodes a 304-amino acid protein with a predicted molecular weight of approximately 35 kDa. Injection of zebrafish Cx35 RNA into paired Xenopus oocytes elicited intercellular electrical coupling with weak voltage sensitivity. In development, Cx35 is first detectable by Northern analysis and RT-PCR, at 2 days post-fertilization (2 dpf), and in the adult it is expressed in the brain and retina. Immunohistochemical analysis revealed that the Cx35 protein is expressed in two sublaminae of the inner plexiform layer of the adult retina. A similar pattern was seen in the 4 and 5 dpf retina, but no labeling was detected in the retina of earlier embryos.

  6. XYY chromosome anomaly and schizophrenia.

    Science.gov (United States)

    Rajagopalan, M; MacBeth, R; Varma, S L

    1998-02-07

    Sex chromosome anomalies have been associated with psychoses, and most of the evidence is linked to the presence of an additional X chromosome. We report a patient with XYY chromosome anomaly who developed schizophrenia.

  7. Formation of complex and unstable chromosomal translocations in yeast.

    Directory of Open Access Journals (Sweden)

    Kristina H Schmidt

    Full Text Available Genome instability, associated with chromosome breakage syndromes and most human cancers, is still poorly understood. In the yeast Saccharomyces cerevisiae, numerous genes with roles in the preservation of genome integrity have been identified. DNA-damage-checkpoint-deficient yeast cells that lack Sgs1, a RecQ-like DNA helicase related to the human Bloom's-syndrome-associated helicase BLM, show an increased rate of genome instability, and we have previously shown that they accumulate recurring chromosomal translocations between three similar genes, CAN1, LYP1 and ALP1. Here, the chromosomal location, copy number and sequence similarity of the translocation targets ALP1 and LYP1 were altered to gain insight into the formation of complex translocations. Among 844 clones with chromosomal rearrangements, 93 with various types of simple and complex translocations involving CAN1, LYP1 and ALP1 were identified. Breakpoint sequencing and mapping showed that the formation of complex translocation types is strictly dependent on the location of the initiating DNA break and revealed that complex translocations arise via a combination of interchromosomal translocation and template-switching, as well as from unstable dicentric intermediates. Template-switching occurred between sequences on the same chromosome, but was inhibited if the genes were transferred to different chromosomes. Unstable dicentric translocations continuously gave rise to clones with multiple translocations in various combinations, reminiscent of intratumor heterogeneity in human cancers. Base substitutions and evidence of DNA slippage near rearrangement breakpoints revealed that translocation formation can be accompanied by point mutations, and their presence in different translocation types within the same clone provides evidence that some of the different translocation types are derived from each other rather than being formed de novo. These findings provide insight into eukaryotic

  8. Cloning of the hexA mismatch-repair gene of Streptococcus pneumoniae and identification of the product.

    Science.gov (United States)

    Martin, B; Prats, H; Claverys, J P

    1985-01-01

    The hexA mismatch repair gene of Streptococcus pneumoniae has been cloned into multicopy plasmid vectors. The cloned hexA gene is expressed as judged from its ability to complement various chromosomal hexA- alleles. Its direction of transcription was defined and the functional limits were localized by original methods relying on homology-dependent integration of nonautonomous chimeric plasmids carrying chromosomal inserts into the chromosome. Comparison of the proteins encoded by recombinant plasmids and by restriction fragments allowed us to identify an Mr 94 000 protein as the probable product of the hexA gene.

  9. Chromosome region-specific libraries for human genome analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kao, Fa-Ten.

    1991-01-01

    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.

  10. Sequence and chromosomal localization of the mouse brevican gene

    DEFF Research Database (Denmark)

    Rauch, U; Meyer, H; Brakebusch, C

    1997-01-01

    Brevican is a brain-specific proteoglycan belonging to the aggrecan family. Phage clones containing the complete mouse brevican open reading frame of 2649 bp and the complete 3'-untranslated region of 341 bp were isolated from a mouse brain cDNA library, and cosmid clones containing the mouse bre...... to an alternative brevican cDNA, coding for a GPI-linked isoform. Single strand conformation polymorphism analysis mapped the brevican gene (Bcan) to chromosome 3 between the microsatellite markers D3Mit22 and D3Mit11....

  11. Chromosomal mosaicism goes global

    Directory of Open Access Journals (Sweden)

    Yurov Yuri B

    2008-11-01

    Full Text Available Intercellular differences of chromosomal content in the same individual are defined as chromosomal mosaicism (alias intercellular or somatic genomic variations or, in a number of publications, mosaic aneuploidy. It has long been suggested that this phenomenon poorly contributes both to intercellular (interindividual diversity and to human disease. However, our views have recently become to change due to a series of communications demonstrated a higher incidence of chromosomal mosaicism in diseased individuals (major psychiatric disorders and autoimmune diseases as well as depicted chromosomal mosaicism contribution to genetic diversity, the central nervous system development, and aging. The later has been produced by significant achievements in the field of molecular cytogenetics. Recently, Molecular Cytogenetics has published an article by Maj Hulten and colleagues that has provided evidences for chromosomal mosaicism to underlie formation of germline aneuploidy in human female gametes using trisomy 21 (Down syndrome as a model. Since meiotic aneuploidy is suggested to be the leading genetic cause of human prenatal mortality and postnatal morbidity, these data together with previous findings define chromosomal mosaicism not as a casual finding during cytogenetic analyses but as a more significant biological phenomenon than previously recognized. Finally, the significance of chromosomal mosaicism can be drawn from the fact, that this phenomenon is involved in genetic diversity, normal and abnormal prenatal development, human diseases, aging, and meiotic aneuploidy, the intrinsic cause of which remains, as yet, unknown.

  12. Comparative sequence analysis of a highly oncogenic but horizontal spread-defective clone of Marek's disease virus.

    Science.gov (United States)

    Spatz, Stephen J; Zhao, Yuguang; Petherbridge, Lawrence; Smith, Lorraine P; Baigent, Susan J; Nair, Venugopal

    2007-12-01

    Marek's disease virus (MDV) is a cell-associated alphaherpesvirus that induces rapid-onset T-cell lymphomas in poultry. MDV isolates vary greatly in pathogenicity. While some of the strains such as CVI988 are non-pathogenic and are used as vaccines, others such as RB-1B are highly oncogenic. Molecular determinants associated with differences in pathogenicity are not completely understood. Comparison of the genome sequences of phenotypically different strains could help to identify molecular determinants of pathogenicity. We have previously reported the construction of bacterial artificial chromosome (BAC) clones of RB-1B from which fully infectious viruses could be reconstituted upon DNA transfection into chicken cells. MDV reconstituted from one of these clones (pRB-1B-5) showed similar in vitro and in vivo replication kinetics and oncogenicity as the parental virus. However, unlike the parental RB-1B virus, the BAC-derived virus showed inability to spread between birds. In order to identify the unique determinants for oncogenicity and the ''non-spreading phenotype'' of MDV derived from this clone, we determined the full-length sequence of pRB-1B-5. Comparative sequence analysis with the published sequences of strains such as Md5, Md11, and CVI988 identified frameshift mutations in RLORF1, protein kinase (UL13), and glycoproteins C (UL44) and D (US6). Comparison of the sequences of these genes with the parental virus indicated that the RLORF1, UL44, and US6 mutations were also present in the parental RB-1B stock of the virus. However with regard to UL13 mutation, the parental RB-1B stock appeared to be a mixture of wild type and mutant viruses, indicating that the BAC cloning has selected a mutant clone. Although further studies are needed to evaluate the role of these genes in the horizontal-spreading defective phenotype, our data clearly indicate that mutations in these genes do not affect the oncogenicity of MDV.

  13. Telomere length status of somatic cell sheep clones and their offspring.

    Science.gov (United States)

    Alexander, Basil; Coppola, Gianfranco; Perrault, Steven D; Peura, Teija T; Betts, Dean H; King, W Allan

    2007-12-01

    This study was carried out to determine the telomere length status of sheep clones and their offspring, and to examine telomere dynamics and chromosomal abnormalities in culture propagated donor cells. Skin samples were collected from somatic cell nuclear transfer-derived sheep clones, and three of their progeny generated by natural mating. Samples were collected from control animals (n = 35), spanning in age from 1 month to 36 months of age. Genomic DNA was extracted from cell/tissue samples and their telomere lengths were assessed by terminal restriction fragment (TRF) analysis. Results revealed: that (a) sheep clones derived from cultured somatic cells have shortened telomere lengths compared to age-matched controls; (b) the offspring derived from natural mating between clones had normal telomere lengths compared to their age-matched counterparts; and donor cell cultures beyond 20 population doublings had significantly (P < 0.05) shortened telomeres and exhibited a higher numerical and structural chromosomal abnormalities.

  14. CHROMOSOMES OF AMERICAN MARSUPIALS.

    Science.gov (United States)

    BIGGERS, J D; FRITZ, H I; HARE, W C; MCFEELY, R A

    1965-06-18

    Studies of the chromosomes of four American marsupials demonstrated that Caluromys derbianus and Marmosa mexicana have a diploid number of 14 chromosomes, and that Philander opossum and Didelphis marsupialis have a diploid number of 22. The karyotypes of C. derbianus and M. mexicana are similar, whereas those of P. opossum and D. marsupialis are dissimilar. If the 14-chromosome karyotype represents a reduction from a primitive number of 22, these observations suggest that the change has occurred independently in the American and Australasian forms.

  15. The gene for human glutaredoxin (GLRX) is localized to human chromosome 5q14

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, C.A.; Holmgren, A. [Karolinska Inst., Stockholm (Sweden); Bajalica, S.; Lagercrantz, J. [Karolinska Hospital, Stockholm (Sweden)

    1996-03-05

    Glutaredoxin is a small protein (12 kDa) catalyzing glutathione-dependent disulfide oxidoreduction reactions in a coupled system with NADPH, GSH, and glutathione reductase. A cDNA encoding the human glutaredoxin gene (HGMW-approved symbol GLRX) has recently been isolated and cloned from a human fetal spleen cDNA library. The screening of a human fetal spleen cDNA library. The screening of a human genomic library in Charon 4A led to the identification of three genomic clones. Using fluorescence in situ hybridization to metaphase chromosomes with one genomic clone as a probe, the human glutaredoxin gene was localized to chromosomal region 5q14. This localization at chromosome 5 was in agreement with the somatic cell hybrid analysis, using DNA from a human-hamster and a human-mouse hybrid panel and using a human glutaredoxin cDNA as a probe. 13 refs., 2 figs.

  16. Trends in Artificial Intelligence.

    Science.gov (United States)

    Hayes, Patrick

    1978-01-01

    Discusses the foundations of artificial intelligence as a science and the types of answers that may be given to the question, "What is intelligence?" The paradigms of artificial intelligence and general systems theory are compared. (Author/VT)

  17. Spontaneous aneuploidy and clone formation in adipose tissue stem cells during different periods of culturing.

    Science.gov (United States)

    Buyanovskaya, O A; Kuleshov, N P; Nikitina, V A; Voronina, E S; Katosova, L D; Bochkov, N P

    2009-07-01

    Cytogenetic analysis of 13 mesenchymal stem cell cultures isolated from normal human adipose tissue was carried out at different stages of culturing. The incidence of chromosomes 6, 8, 11, and X aneuploidy and polyploidy was studied by fluorescent in situ hybridization. During the early passages, monosomal cells were more often detected than trisomal ones. A clone with chromosome 6 monosomy was detected in three cultures during late passages.

  18. Placentation in cloned cattle

    DEFF Research Database (Denmark)

    Miglino, M A; Pereira, F T V; Visintin, J A

    2007-01-01

    To elucidate the morphological differences between placentas from normal and cloned cattle pregnancies reaching term, the umbilical cord, placentomes and interplacentomal region of the fetal membranes were examined macroscopically as well as by light and scanning electron microscopy. In pregnancies...... than one primary villus, as opposed to a single villus in non-cloned placentae. Scanning electron microscopy of blood vessel casts revealed that there was also more than one stem artery per villous tree and that the ramification of the vessels failed to form dense complexes of capillary loops...

  19. Artificiality in Social Sciences

    OpenAIRE

    Rennard, Jean-Philippe

    2007-01-01

    This text provides with an introduction to the modern approach of artificiality and simulation in social sciences. It presents the relationship between complexity and artificiality, before introducing the field of artificial societies which greatly benefited from the computer power fast increase, gifting social sciences with formalization and experimentation tools previously owned by "hard" sciences alone. It shows that as "a new way of doing social sciences", artificial societies should undo...

  20. Artificial life and Piaget.

    Science.gov (United States)

    Mueller, Ulrich; Grobman, K H.

    2003-04-01

    Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

  1. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  2. [Sex chromosomes and meiosis].

    Science.gov (United States)

    Guichaoua, M-R; Geoffroy-Siraudin, C; Tassistro, V; Ghalamoun-Slaimi, R; Perrin, J; Metzler-Guillemain, C

    2009-01-01

    Sex chromosome behaviour fundamentally differs between male and female meiosis. In oocyte, X chromosomes synapse giving a XX bivalent which is not recognizable in their morphology and behaviour from autosomal bivalents. In human male, X and Y chromosomes differ from one another in their morphology and their genetic content, leading to a limited pairing and preventing genetic recombination, excepted in homologous region PAR1. During pachytene stage of the first meiotic prophase, X and Y chromosomes undergo a progressive condensation and form a transcriptionally silenced peripheral XY body. The condensation of the XY bivalent during pachytene stage led us to describe four pachytene substages and to localize the pachytene checkpoint between substages 2 and 3. We also defined the pachytene index (PI=P1+P2/P1+P2+P3+P4) which is always less than 0.50 in normal meiosis. XY body undergoes decondensation at diplotene stage, but transcriptional inactivation of the two sex chromosomes or Meiotic Sex Chromosome Inactivation (MSCI) persists through to the end of spermatogenesis. Sex chromosome inactivation involves several proteins, some of them were now identified. Two isoforms of the HP1 protein, HP1beta and HP1gamma, are involved in the facultative heterochromatinization of the XY body, but the initiation of this process involves the phosphorylation of the protein H2AX by the kinase ATR whose recruitment depends on BRCA1. Extensive researches on the inactivation of the sex chromosomes during male meiosis will allow to a better understanding of some male infertilities.

  3. Chromosome doubling method

    Science.gov (United States)

    Kato, Akio

    2006-11-14

    The invention provides methods for chromosome doubling in plants. The technique overcomes the low yields of doubled progeny associated with the use of prior techniques for doubling chromosomes in plants such as grasses. The technique can be used in large scale applications and has been demonstrated to be highly effective in maize. Following treatment in accordance with the invention, plants remain amenable to self fertilization, thereby allowing the efficient isolation of doubled progeny plants.

  4. Activation of X Chromosome Inactivation

    NARCIS (Netherlands)

    C.M. Maduro (Cheryl)

    2016-01-01

    markdownabstractIn mammals, males are the heterogametic sex having an X chromosome and a Y chromosome whereas females have two X chromosomes. Despite originating from an ancient homologous autosomal pair, the X and Y chromosome now differ greatly in size and gene content after ~180 MY of evolution.

  5. Why clone flies? Using cloned Drosophila to monitor epigenetic defects.

    Science.gov (United States)

    Haigh, Andrew J; Lloyd, Vett K

    2007-01-01

    Since the birth of the first cloned sheep in 1996, advances in nuclear transplantation have led to both the creation of genetically tailored stem cells and the generation of a number of cloned organisms. The list of cloned animals reared to adulthood currently includes the frog, sheep, mouse, cow, goat, pig, rabbit, cat, zebrafish, mule, horse, rat and dog. The addition of Drosophila to this elite bestiary of cloned animals has prompted the question - why clone flies? Organisms generated by nuclear transplantation suffer from a high rate of associated defects, and many of these defects appear to be related to aberrant genomic imprinting. Imprinted gene expression also appears to be compromised in Drosophila clones. Proper imprinted gene regulation relies on a suite of highly conserved chromatin-modifying genes first identified in Drosophila. Thus, Drosophila can potentially be used to study epigenetic dysfunction in cloned animals and to screen for genetic and epigenetic conditions that promote the production of healthy clones.

  6. The orphan nuclear receptor ROR{alpha} (RORA) maps to a conserved region of homology on human chromosome 15q21-q22 and mouse chromosome 9

    Energy Technology Data Exchange (ETDEWEB)

    Giguere, V. [McGill Univ., Montreal (Canada); Beatty, B.; Squire, J. [Hospital for Sick Children, Toronto (Canada)] [and others

    1995-08-10

    ROR{alpha} is a novel member of the steroid/thyroid/retinoid receptor superfamily with unique DNA-binding properties. We have mapped the RORA gene by fluorescence in situ hybridization to human chromosome 15q21-q22. To map the mouse Rora gene, a partial mouse cDNA clone was isolated from brain. Using interspecific backcross analysis, we have mapped the Rora gene to mouse chromosome 9. This places the human RORA gene in the proximity of the PML gene, which is involved in a reciprocal chromosomal translocation t(15:17) with the RARA gene in patients with acute promyelocytic leukemia. 13 refs., 2 figs.

  7. Vibrio chromosomes share common history

    Directory of Open Access Journals (Sweden)

    Gevers Dirk

    2010-05-01

    Full Text Available Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II were identified from 19 sequenced Vibrionales genomes and their phylogenetic comparison suggests consistent phylogenies for each chromosome. Additionally, study of the gene organization and phylogeny of the respective origins of replication confirmed the shared history. Conclusions Thus, while elements within the chromosomes may have experienced significant genetic mobility, the backbones share a common history. This allows conclusions based on multilocus sequence analysis (MLSA for one chromosome to be applied equally to both chromosomes.

  8. The Cloning of America.

    Science.gov (United States)

    Dobson, Judith E.; Dobson, Russell L.

    1981-01-01

    Proposes that the U.S. school system purports to prize human variability, but many educators are engaged in activities that seek to homogenize students. Describes these activities, including diagnosis, labeling, ability grouping, and positive reinforcement. Presents suggestions for counselors to combat sources of cloning and self-validation. (RC)

  9. Clip, connect, clone

    DEFF Research Database (Denmark)

    Fujima, Jun; Lunzer, Aran; Hornbæk, Kasper

    2010-01-01

    using three mechanisms: clipping of input and result elements from existing applications to form cells on a spreadsheet; connecting these cells using formulas, thus enabling result transfer between applications; and cloning cells so that multiple requests can be handled side by side. We demonstrate...

  10. Asian Yellow Goat Cloned

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ It was released on August 24,2005 by Prof. CHEN Dayuan (Da-Yuan Chen) from the CAS Institute of Zoology that the first success in cloning the Asian Yellow Goat by nuclear transfer had recently been achieved in east China's Shandong Province.

  11. An improved method for producing radiation hybrids applied to human chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, C.L.

    1992-01-01

    At the initiation of the grant we had just produced radiation hybrids from a monochromosomal microcell hybrid containing human chromosome 19 as its only human component. Radiation hybrids were produced using doses of radiation ranging from 1000--8000 rads. Lethally irradiated cells were then fused to hamster recipients (CHTG49) and selected for growth in histidinol. Approximately 240 clones were isolated and 75 clones were expanded for the isolation of DNA. This report describes in situ hybridization studies and the introduction of markers into human chromosome 19.

  12. Interference in DNA replication can cause mitotic chromosomal breakage unassociated with double-strand breaks.

    Directory of Open Access Journals (Sweden)

    Mari Fujita

    Full Text Available Morphological analysis of mitotic chromosomes is used to detect mutagenic chemical compounds and to estimate the dose of ionizing radiation to be administered. It has long been believed that chromosomal breaks are always associated with double-strand breaks (DSBs. We here provide compelling evidence against this canonical theory. We employed a genetic approach using two cell lines, chicken DT40 and human Nalm-6. We measured the number of chromosomal breaks induced by three replication-blocking agents (aphidicolin, 5-fluorouracil, and hydroxyurea in DSB-repair-proficient wild-type cells and cells deficient in both homologous recombination and nonhomologous end-joining (the two major DSB-repair pathways. Exposure of cells to the three replication-blocking agents for at least two cell cycles resulted in comparable numbers of chromosomal breaks for RAD54(-/-/KU70(-/- DT40 clones and wild-type cells. Likewise, the numbers of chromosomal breaks induced in RAD54(-/-/LIG4(-/- Nalm-6 clones and wild-type cells were also comparable. These data indicate that the replication-blocking agents can cause chromosomal breaks unassociated with DSBs. In contrast with DSB-repair-deficient cells, chicken DT40 cells deficient in PIF1 or ATRIP, which molecules contribute to the completion of DNA replication, displayed higher numbers of mitotic chromosomal breaks induced by aphidicolin than did wild-type cells, suggesting that single-strand gaps left unreplicated may result in mitotic chromosomal breaks.

  13. The First Human Cloned Embryo.

    Science.gov (United States)

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  14. Animal Cloning and Food Safety

    Science.gov (United States)

    ... For Consumers Home For Consumers Consumer Updates Animal Cloning and Food Safety Share Tweet Linkedin Pin it ... evaluate the issue. back to top FDA Studies Cloning For more than five years, CVM scientists studied ...

  15. Structural organization of the inactive X chromosome in the mouse.

    Science.gov (United States)

    Giorgetti, Luca; Lajoie, Bryan R; Carter, Ava C; Attia, Mikael; Zhan, Ye; Xu, Jin; Chen, Chong Jian; Kaplan, Noam; Chang, Howard Y; Heard, Edith; Dekker, Job

    2016-07-28

    X-chromosome inactivation (XCI) involves major reorganization of the X chromosome as it becomes silent and heterochromatic. During female mammalian development, XCI is triggered by upregulation of the non-coding Xist RNA from one of the two X chromosomes. Xist coats the chromosome in cis and induces silencing of almost all genes via its A-repeat region, although some genes (constitutive escapees) avoid silencing in most cell types, and others (facultative escapees) escape XCI only in specific contexts. A role for Xist in organizing the inactive X (Xi) chromosome has been proposed. Recent chromosome conformation capture approaches have revealed global loss of local structure on the Xi chromosome and formation of large mega-domains, separated by a region containing the DXZ4 macrosatellite. However, the molecular architecture of the Xi chromosome, in both the silent and expressed regions,remains unclear. Here we investigate the structure, chromatin accessibility and expression status of the mouse Xi chromosome in highly polymorphic clonal neural progenitors (NPCs) and embryonic stem cells. We demonstrate a crucial role for Xist and the DXZ4-containing boundary in shaping Xi chromosome structure using allele-specific genome-wide chromosome conformation capture (Hi-C) analysis, an assay for transposase-accessible chromatin with high throughput sequencing (ATAC-seq) and RNA sequencing. Deletion of the boundary disrupts mega-domain formation, and induction of Xist RNA initiates formation of the boundary and the loss of DNA accessibility. We also show that in NPCs, the Xi chromosome lacks active/inactive compartments and topologically associating domains (TADs), except around genes that escape XCI. Escapee gene clusters display TAD-like structures and retain DNA accessibility at promoter-proximal and CTCF-binding sites. Furthermore, altered patterns of facultative escape genes indifferent neural progenitor clones are associated with the presence of different TAD

  16. Probabilistic Cloning and Quantum Computation

    Institute of Scientific and Technical Information of China (English)

    GAO Ting; YAN Feng-Li; WANG Zhi-Xi

    2004-01-01

    @@ We discuss the usefulness of quantum cloning and present examples of quantum computation tasks for which the cloning offers an advantage which cannot be matched by any approach that does not resort to quantum cloning.In these quantum computations, we need to distribute quantum information contained in the states about which we have some partial information. To perform quantum computations, we use a state-dependent probabilistic quantum cloning procedure to distribute quantum information in the middle of a quantum computation.

  17. Affected chromosome homeostasis and genomic instability of clonal yeast cultures.

    Science.gov (United States)

    Adamczyk, Jagoda; Deregowska, Anna; Panek, Anita; Golec, Ewelina; Lewinska, Anna; Wnuk, Maciej

    2016-05-01

    Yeast cells originating from one single colony are considered genotypically and phenotypically identical. However, taking into account the cellular heterogeneity, it seems also important to monitor cell-to-cell variations within a clone population. In the present study, a comprehensive yeast karyotype screening was conducted using single chromosome comet assay. Chromosome-dependent and mutation-dependent changes in DNA (DNA with breaks or with abnormal replication intermediates) were studied using both single-gene deletion haploid mutants (bub1, bub2, mad1, tel1, rad1 and tor1) and diploid cells lacking one active gene of interest, namely BUB1/bub1, BUB2/bub2, MAD1/mad1, TEL1/tel1, RAD1/rad1 and TOR1/tor1 involved in the control of cell cycle progression, DNA repair and the regulation of longevity. Increased chromosome fragility and replication stress-mediated chromosome abnormalities were correlated with elevated incidence of genomic instability, namely aneuploid events-disomies, monosomies and to a lesser extent trisomies as judged by in situ comparative genomic hybridization (CGH). The tor1 longevity mutant with relatively balanced chromosome homeostasis was found the most genomically stable among analyzed mutants. During clonal yeast culture, spontaneously formed abnormal chromosome structures may stimulate changes in the ploidy state and, in turn, promote genomic heterogeneity. These alterations may be more accented in selected mutated genetic backgrounds, namely in yeast cells deficient in proper cell cycle regulation and DNA repair.

  18. Physical Characterization of human centromeric regions using transformation-associated recombination cloning technology

    Energy Technology Data Exchange (ETDEWEB)

    Vladimir Larionov, Ph D

    2007-06-05

    A special interest in the organization of human centromeric DNA was stimulated a few years ago when two independent groups succeeded in reconstituting a functional human centromere, using constructs carrying centromere-specific alphoid DNA arrays. This work demonstrated the importance of DNA components in mammalian centromeres and opened a way for studying the structural requirements for de novo kinetochore formation and for construction of human artificial chromosomes (HACs) with therapeutic potential. To elucidate the structural requirements for formation of HACs with a functional kinetochore, we developed a new method for cloning of large DNA fragments for human centromeric regions that can be used as a substrate for HAC formation. This method exploits in vivo recombination in yeast (TAR cloning). In addition, a new strategy for the construction of alphoid DNA arrays was developed in our lab. The strategy involves the construction of uniform or hybrid synthetic alphoid DNA arrays by the RCA-TAR technique. This technique comprises two steps: rolling circle amplification of an alphoid DNA dimer and subsequent assembling of the amplified fragments by in vivo homologous recombination in yeast (Figure 1). Using this system, we constructed a set of different synthetic alphoid DNA arrays with a predetermined sequence varying in size from 30 to 140 kb and demonstrated that some of the arrays are competent in HAC formation. Because any nucleotide can be changed in a dimer before its amplification, this new technique is optimal for identifying the structural requirements for de novo kinetochore formation in HACs. Moreover, the technique makes possible to introduce into alphoid DNA arrays recognition sites for DNA-binding proteins. We have made the following progress on the studying of human centromeric regions using transformation-associated recombination cloning technology: i) minimal size of alphoid DNA array required for de novo kinetochore formation was estimated; ii

  19. "Chromosome": a knowledge-based system for the chromosome classification.

    Science.gov (United States)

    Ramstein, G; Bernadet, M

    1993-01-01

    Chromosome, a knowledge-based analysis system has been designed for the classification of human chromosomes. Its aim is to perform an optimal classification by driving a tool box containing the procedures of image processing, pattern recognition and classification. This paper presents the general architecture of Chromosome, based on a multiagent system generator. The image processing tool box is described from the met aphasic enhancement to the fine classification. Emphasis is then put on the knowledge base intended for the chromosome recognition. The global classification process is also presented, showing how Chromosome proceeds to classify a given chromosome. Finally, we discuss further extensions of the system for the karyotype building.

  20. Persistent chromosome damage induced by localized radiotherapy for lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Zaslav, A.L.; Stamberg, J.; Shende, A.

    1988-02-01

    A fibroblast culture was established from a lymph node biopsy of a patient with non-Hodgkin lymphoma, 9 months after chemotherapy and intensive therapeutic x-irradiation of the area. In contrast with blood and bone marrow, which were chromosomally normal, all cells of the lymph node were chromosomally abnormal, with numerous clones having multiple structural abnormalities. Numerical abnormalities (trisomies and monosomies) were not found. Structural abnormalities included translocations, terminal deletions, and pericentric inversions, with an excess of centromeric breakpoints being the only apparent deviation from a random distribution of breakpoints. None of the rearrangements associated with malignant lymphoma were seen, indicating that the chromosome abnormalities in the lymph stroma were radiation-associated, not disease-associated. These acquired changes may be a cause of additional malignant transformation.

  1. Structural comparison of three types of staphylococcal cassette chromosome mec integrated in the chromosome in methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Ito, T; Katayama, Y; Asada, K; Mori, N; Tsutsumimoto, K; Tiensasitorn, C; Hiramatsu, K

    2001-05-01

    The beta-lactam resistance gene mecA of Staphylococcus aureus is carried by a novel mobile genetic element, designated staphylococcal cassette chromosome mec (SCCmec), identified in the chromosome of a Japanese methicillin-resistant S. aureus (MRSA) strain. We now report identification of two additional types of mecA-carrying genetic elements found in the MRSA strains isolated in other countries of the world. There were substantial differences in the size and nucleotide sequences between the elements and the SCCmec. However, new elements shared the chromosomal integration site with the SCCmec. Structural analysis of the new elements revealed that they possessed all of the salient features of the SCCmec: conserved terminal inverted repeats and direct repeats at the integration junction points, conserved genetic organization around the mecA gene, and the presence of cassette chromosome recombinase (ccr) genes responsible for the movements of SCCmec. The elements, therefore, were considered to comprise the SCCmec family of staphylococcal mobile genetic elements together with the previously identified SCCmec. Among 38 epidemic MRSA strains isolated in 20 countries, 34 were shown to possess one of the three typical SCCmec elements on the chromosome. Our findings indicated that there are at least three distinct MRSA clones in the world with different types of SCCmec in their chromosome.

  2. Identification and characterization of a new type of asymmetrical dicentric chromosome derived from a single maternal chromosome 18.

    Science.gov (United States)

    Lin, C C; Li, Y-C; Liu, P-P; Hsieh, L-J; Cheng, Y-M; Teng, R-H; Shi, S-L; Tsai, F-J

    2007-01-01

    Molecular cytogenetic analysis identified a new type of dicentric chromosome involving different breakpoints at 18q in a female fetus. The chromosome anomaly was designated as an asymmetrical pseudoisodicentric chromosome 18, 46,XX,psu dic(18)(pter-->q11.2::q21.3-->pter)mat. A series of BAC clones for 18q11.2 and q21.3 regions were used to identify one breakpoint within the region q11.2 between 19.8 and 21.6 Mb from the telomere of 18p and another breakpoint within q21.3 between 55.4 and 56.9 Mb from the telomere of 18p by FISH analysis. Real-time quantitative PCR and microsatellite analysis further verified that the dicentric chromosome was maternal in origin and resulted from a break-reunion between sister chromatids of a single maternal chromosome. We propose that a loop-type configuration of sister chromatids took place and that the break-reunion occurred at cross sites of the loop to form an asymmetrical isodicentric chromosome during either mitosis or meiosis. In this case, the asymmetrical pseudoisodicentric resulted in an 18pter--> q11.2 duplication and an 18q21.3-->qter deletion, which could have led to certain dysmorphic features of 18q- syndrome in this fetus.

  3. Quality and safety of bovine clones and their products.

    Science.gov (United States)

    Heyman, Y; Chavatte-Palmer, P; Fromentin, G; Berthelot, V; Jurie, C; Bas, P; Dubarry, M; Mialot, J P; Remy, D; Richard, C; Martignat, L; Vignon, X; Renard, J P

    2007-08-01

    A multidisciplinary research programme was developed to get a scientific expertise for the quality assessment of products obtained from cloned livestock. Thirty-seven bovine Holstein female clones of five different genotypes and their products were analysed in comparison with 38 control animals obtained by conventional artificial insemination and raised under the same conditions at the same experimental farm. Animal evaluation included over 150 criteria and more than 10 000 measurements to check the physiological status and health over a 3-year period. All the parameters studied were in the normal range for age and breed, but some significant differences were detected between clone and control groups in terms of delayed onset of puberty in clones, higher neutrophil counts in haematology or lower biochemical plasma concentrations of gamma glutamyl transferase. Milk and meat analyses were conformable to expected values. We, however, found some differences in fatty acid (FA) composition of milk and muscle suggesting a possible deviation in lipid metabolism as assessed by higher delta-9 desaturase activity indexes in both milk and muscles from clones compared with controls. Repeated muscle biopsies in the semitendinosus muscle of the same animals demonstrated a higher oxidative activity in muscle of young clones (8 months of age) compared with controls, suggesting a delayed muscle maturation in clones. Nutritional evaluation of milk and meat using the rat feeding trials did not show any difference between clone and control products for food intake, growth rate, body composition of the rats, nor for possible allergenicity. Possible reactivation of bovine endogenous retroviruses (BERVs) was analysed and compared between normal and cloned cattle. As expected, these BERV sequences are not transcribed and no RNA was detected in the blood of clones, donor animals or controls; therefore, it may be assumed that the sanitary risk associated with BERV sequences is not higher in

  4. Transformation of Bacillus Subtilis with cloned thymidylate synthetases

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, Edward M.

    1980-01-01

    Bacillus subtilis carries two genes, thyA and thyB, each encoding different protein products, with thymidylate synthetase (TSase) activity. Either of these genes alone is sufficient for thymidine independence in B. subtilis. In addition there exist two B. subtilis temperate bacteriophages which upon infection of thymine requiring auxotrophs results in conversion of the organism to thymine independence. Chimeric plasmids selected for Thy/sup +/ transforming activity in E. coli were constructed and then used as a source of defined highly enriched DNA with which to transform competent B. subtilis. These plasmids were studied for their: (1) abiility to transform B. subtilis to thymine independence; (2) site of integration within the B. subtilis chromosome upon transformation; (3) phenotype of Thy/sup +/ plasmid generated transformants; and (4) nucleotide sequence homology among the cloned DNA fragments conferring thymine independence. Plasmids containing the two bacteriophage thy genes displayed the phenotype associated with thyA, whereas the plasmids containing the cloned B. subtilis chromosomal genes displayed the phenotype associated with thyB. Utilizing similar technology, the ability of an entirely foreign hybred bacterial plasmiid to transform B. subtilis was examined. In this case the gene from E. coli encoding thymidylate synthetase was cloned in the plasmid pBR322. The resulting chimeric plasmid was effective in transforming both E. coli and B. subtilis to thymine prototrophy. Uncloned linear E. coli chromosomal DNA was unable to transform thymine requiring strains of B. subtilis to thymine independence. Although the Thy/sup +/ transformants of E. coli contained plasmid DNA, the Thy/sup +/ transformants derived from the transformation of B. subtilis did not contain detectable extrachromosomal DNA. Instead the DNA from the chimeric plasmid was integrated into the chromosome of B. subtilis. (ERB)

  5. Chromosome numbers in Bromeliaceae

    Directory of Open Access Journals (Sweden)

    Cotias-de-Oliveira Ana Lúcia Pires

    2000-01-01

    Full Text Available The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. utriculosa. The chromosome number of all species was determined for the first time, except for Billbergia chlorosticta and Cryptanthus bahianus. Our data supports the hypothesis of a basic number of x = 25 for the Bromeliaceae family and decreasing aneuploidy in the genus Cryptanthus.

  6. Those amazing dinoflagellate chromosomes

    Institute of Scientific and Technical Information of China (English)

    PETER J RIZZO

    2003-01-01

    Dinoflagellates are a very large and diverse group of eukaryotic algae that play a major role in aquatic food webs of both fresh water and marine habitats. Moreover, the toxic members of this group pose a health threat in the form of red tides. Finally, dinoflagellates are of great evolutionary importance,because of their taxonomic position, and their unusual chromosome structure and composition. While the cytoplasm of dinoflagellates is typically eukaryotic, the nucleus is unique when compared to the nucleus of other eukaryotes. More specifically, while the chromosomes of all other eukaryotes contain histones,dinoflagellate chromosomes lack histones completely. There are no known exceptions to this observation: all dinoflagellates lack histones, and all other eukaryotes contain histones. Nevertheless, dinoflagellates remain a relatively unstudied group of eukaryotes.

  7. Entering the Clone Age

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Suppose you make your parents so happy,they decide to have another baby just like you.It might be flattering,but how would you feel about having a little brother or sister who is also your twin? A laboratory experiment conducted last fall suggests it may someday be possible.For the first time ever,scientists made exact copies, or clones, of a human embryo.

  8. Post-death cloning of endangered Jeju black cattle (Korean native cattle): fertility and serum chemistry in a cloned bull and cow and their offspring.

    Science.gov (United States)

    Kim, Eun Young; Song, Dong Hwan; Park, Min Jee; Park, Hyo Young; Lee, Seung Eun; Choi, Hyun Yong; Moon, Jeremiah Jiman; Kim, Young Hoon; Mun, Seong Ho; Oh, Chang Eon; Ko, Moon Suck; Lee, Dong Sun; Riu, Key Zung; Park, Se Pill

    2013-12-17

    To preserve Jeju black cattle (JBC; endangered native Korean cattle), a pair of cattle, namely a post-death cloned JBC bull and cow, were produced by somatic cell nuclear transfer (SCNT) in a previous study. In the present study, we examined the in vitro fertilization and reproductive potentials of these post-death cloned animals. Sperm motility, in vitro fertilization and developmental capacity were examined in a post-death cloned bull (Heuk Oll Dolee) and an extinct nuclear donor bull (BK94-13). We assessed reproductive ability in another post-death cloned cow (Heuk Woo Sunee) using cloned sperm for artificial insemination (AI). There were no differences in sperm motility or developmental potential of in vitro fertilized embryos between the post-death cloned bull and its extinct nuclear donor bull; however, the embryo development ratio was slightly higher in the cloned sperm group than in the nuclear donor sperm group. After one attempt at AI, the post-death cloned JBC cow became pregnant, and gestation proceeded normally until day 287. From this post-death cloned sire and dam, a JBC male calf (Heuk Woo Dolee) was delivered naturally (weight, 25 kg). The genetic paternity/maternity of the cloned JBC bull and cow with regard to their offspring was confirmed using International Society for Animal Genetics standard microsatellite markers. Presently, Heuk Woo Dolee is 5 months of age and growing normally. In addition, there were no significant differences in blood chemistry among the post-death cloned JBC bull, the cow, their offspring and cattle bred by AI. This is the first report showing that a pair of cattle, namely, a post-death cloned JBC bull and cow, had normal fertility. Therefore, SCNT can be used effectively to increase the population of endangered JBC.

  9. A novel nucleo-cytoplasmic hybrid clone formed via androgenesis in polyploid gibel carp

    Directory of Open Access Journals (Sweden)

    Zhou Li

    2011-03-01

    Full Text Available Abstract Background Unisexual vertebrates have been demonstrated to reproduce by gynogenesis, hybridogenesis, parthenogenesis, or kleptogenesis, however, it is uncertain how the reproduction mode contributes to the clonal diversity. Recently, polyploid gibel carp has been revealed to possess coexisting dual modes of unisexual gynogenesis and sexual reproduction and to have numerous various clones. Using sexual reproduction mating between clone D female and clone A male and subsequent 7 generation multiplying of unisexual gynogenesis, we have created a novel clone strain with more than several hundred millions of individuals. Here, we attempt to identify genetic background of the novel clone and to explore the significant implication for clonal diversity contribution. Methods Several nuclear genome markers and one cytoplasmic marker, the mitochondrial genome sequence, were used to identify the genetic organization of the randomly sampled individuals from different generations of the novel clone. Results Chromosome number, Cot-1 repetitive DNA banded karyotype, microsatellite patterns, AFLP profiles and transferrin alleles uniformly indicated that nuclear genome of the novel clone is identical to that of clone A, and significantly different from that of clone D. However, the cytoplasmic marker, its complete mtDNA genome sequence, is same to that of clone D, and different from that of clone A. Conclusions The present data indicate that the novel clone is a nucleo-cytoplasmic hybrid between the known clones A and D, because it originates from the offspring of gonochoristic sexual reproduction mating between clone D female and clone A male, and contains an entire nuclear genome from the paternal clone A and a mtDNA genome (cytoplasm from the maternal clone D. It is suggested to arise via androgenesis by a mechanism of ploidy doubling of clone A sperm in clone D ooplasm through inhibiting the first mitotic division. Significantly, the selected nucleo

  10. Ethical issues in livestock cloning.

    Science.gov (United States)

    Thompson, P B

    1999-01-01

    Although cloning may eventually become an important technology for livestock production, four ethical issues must be addressed before the practice becomes widespread. First, researchers must establish that the procedure is not detrimental to the health or well-being of affected animals. Second, animal research institutions should evaluate the net social benefits to livestock producers by weighing the benefits to producers against the opportunity cost of research capacity lost to biomedical projects. Third, scientists should consider the indirect effects of cloning research on the larger ethical issues surrounding human cloning. Finally, the market structure for products of cloned animals should protect individual choice, and should recognize that many individuals find the prospect of cloning (or consuming cloned animals) repugnant. Analysis of these four issues is complicated by spurious arguments alleging that cloning will have a negative impact on environment and genetic diversity.

  11. Cloning-free CRISPR

    Directory of Open Access Journals (Sweden)

    Mandana Arbab

    2015-11-01

    Full Text Available We present self-cloning CRISPR/Cas9 (scCRISPR, a technology that allows for CRISPR/Cas9-mediated genomic mutation and site-specific knockin transgene creation within several hours by circumventing the need to clone a site-specific single-guide RNA (sgRNA or knockin homology construct for each target locus. We introduce a self-cleaving palindromic sgRNA plasmid and a short double-stranded DNA sequence encoding the desired locus-specific sgRNA into target cells, allowing them to produce a locus-specific sgRNA plasmid through homologous recombination. scCRISPR enables efficient generation of gene knockouts (∼88% mutation rate at approximately one-sixth the cost of plasmid-based sgRNA construction with only 2 hr of preparation for each targeted site. Additionally, we demonstrate efficient site-specific knockin of GFP transgenes without any plasmid cloning or genome-integrated selection cassette in mouse and human embryonic stem cells (2%–4% knockin rate through PCR-based addition of short homology arms. scCRISPR substantially lowers the bar on mouse and human transgenesis.

  12. Secure the Clones

    CERN Document Server

    Jensen, Thomas; Pichardie, David

    2012-01-01

    Exchanging mutable data objects with untrusted code is a delicate matter because of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java stress the importance of using defensive copying before accepting or handing out references to an internal mutable object. However, implementation of a copy method (like clone()) is entirely left to the programmer. It may not provide a sufficiently deep copy of an object and is subject to overriding by a malicious sub-class. Currently no language-based mechanism supports secure object cloning. This paper proposes a type-based annotation system for defining modular copy policies for class-based object-oriented programs. A copy policy specifies the maximally allowed sharing between an object and its clone. We present a static enforcement mechanism that will guarantee that all classes fulfil their copy policy, even in the presence of overriding of copy methods, and establish the semantic correctness of the ove...

  13. 用高分辨G带和人工细菌染色体荧光原位杂交技术分析中国儿童孤独症患者的染色体改变%Detection of chromosome aberrations in Chinese children with autism using G-banding and BAC FISH

    Institute of Scientific and Technical Information of China (English)

    刘青杰; 陈晓宁; 沈岩; 马芬; 李丹; 王晓维; 田文雁; 陈艳; 封江彬; 陆雪; 陈德清

    2005-01-01

    Objective To detect the characteristic chromosomal changes in Chinese children with infantile autism. Methods Chromosome aberrations in 68 cases of infantile autism were analyzed by high-resolution G-banding and fluorescence in situ hybridization (FISH) with bacterial artificial chromosome (BAC) clones. Results Chromosomal changes were detected in 4 cases by high-resolution G-banding: one case with t(4;6)(q23-24;p21), one case with longer p arm of chromosome 21 (21p+), and two cases with pericentric inversion of chromosome 9 (inv(9)) which was confirmed by C-banding. BAC FISH analysis was performed to confirm these observations and changes in chromosomes 2, 7 and 15, which are often found in autistic children. There could exist the translocation of t(4;6) (q25-26;p21.1). Chromosome changes often reported previously in chromosomes 2, 7 and 15 were not detected in this study. Inv(9) and 21p+ were not confirmed with present BAC clones. Conclusion Chromosomal changes were detected in four cases of infantile autism, with a detectability of 5.9%, far lower than that (10% to 48%) reported in literature. The breakpoint of translocation could be detected more accurately using BAC FISH method.%目的检测中国儿童孤独症患者的特征性染色体改变.方法应用高分辨G带和人工细菌染色体(bacterial artificial chromosome, BAC)荧光原位杂交(flourescence in situ hybridization, FISH)分析68例中国儿童孤独症患者的染色体改变.结果用G带分析观察到有染色体改变的4例患者,分别为1例t(4;6)(q23-24;p21)、1例21p+和2例9号染色体臂间倒位.BAC FISH进一步证实易位病例,而且更精确[t(4;6)(q25-26;p21.1)];涉及7号、15号、2号染色体的BAC FISH均未观察到文献中报道的染色体改变;而9号染色体的臂间倒位和21p+因无BAC克隆而无法证实.结论用G带和BAC FISH发现少数中国孤独症患者有染色体改变,但远没有文献中报道的10%~48%那么高.BAC FISH有助于精确地确定染色体易位断裂点.

  14. Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

    Directory of Open Access Journals (Sweden)

    Yerle Martine

    2003-11-01

    Full Text Available Abstract A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+ translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5 were elaborated and hybridised independently on chromosomal preparations of the bull who was a carrier of the mosaic translocation. The impossibility of differentiating chromosomes 2 and der(2 from other chromosomes of the metaphases did not allow the production of painting probes for these chromosomes. For all experiments, the quality of painting was comparable to that usually observed with probes obtained from flow-sorted chromosomes. The results obtained allowed confirmation of the interpretations proposed with G-banding karyotype analyses. In the bovine case, however, the reciprocity of the translocation could not be proven. The results presented in this paper show the usefulness of the microdissection technique for characterising chromosomal rearrangements in species for which commercial probes are not available. They also confirmed that the main limiting factor of the technique is the quality of the chromosomal preparations, which does not allow the identification of target chromosomes or chromosome fragments in all cases.

  15. Artificial cognition architectures

    CERN Document Server

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  16. CLONING, SEQUENCING, AND EXPRESSION OF BACILLUS-SUBTILIS GENES INVOLVED IN ATP-DEPENDENT NUCLEASE SYNTHESIS

    NARCIS (Netherlands)

    KOOISTRA, J; VENEMA, G

    1991-01-01

    The genes encoding the subunits of the Bacillus subtilis ATP-dependent nuclease (add genes) have been cloned. The genes were located on an 8.8-kb SalI-SmaI chromosomal DNA fragment. Transformants of a recBCD deletion mutant of Escherichia coli with plasmid pGV1 carrying this DNA fragment showed ATP-

  17. Cloning and characterization of a critical regulator for pre-harvest sprouting in Wheat

    Science.gov (United States)

    Sprouting of grains in mature spikes before harvest is a major problem in wheat (Triticum aestivum) production worldwide. We cloned and characterized a gene underlying a wheat quantitative trait locus (QTL) on the short arm of chromosome 3A for pre-harvest sprouting (PHS) resistance in white wheat u...

  18. Cytological studies on adventitious shoots and minitubers of a monoploid potato clone

    NARCIS (Netherlands)

    Hermelink, J; Jacobsen, Evert; Pijnacker, Laas; Witholt, Bernard; de Vries, J.N.; Feenstra, W.J.

    1988-01-01

    A three step procedure for adventitious shoot regeneration on leaf explants of monoploid potato clone H7322 and a minituber induction procedure on stem segments have been described. Chromosome counts on 92 adventitious shoots showed that 85% of them had been polyploidized, i.e., 71% were diploid, 1%

  19. The Staurotypus turtles and aves share the same origin of sex chromosomes but evolved different types of heterogametic sex determination.

    Science.gov (United States)

    Kawagoshi, Taiki; Uno, Yoshinobu; Nishida, Chizuko; Matsuda, Yoichi

    2014-01-01

    Reptiles have a wide diversity of sex-determining mechanisms and types of sex chromosomes. Turtles exhibit temperature-dependent sex determination and genotypic sex determination, with male heterogametic (XX/XY) and female heterogametic (ZZ/ZW) sex chromosomes. Identification of sex chromosomes in many turtle species and their comparative genomic analysis are of great significance to understand the evolutionary processes of sex determination and sex chromosome differentiation in Testudines. The Mexican giant musk turtle (Staurotypus triporcatus, Kinosternidae, Testudines) and the giant musk turtle (Staurotypus salvinii) have heteromorphic XY sex chromosomes with a low degree of morphological differentiation; however, their origin and linkage group are still unknown. Cross-species chromosome painting with chromosome-specific DNA from Chinese soft-shelled turtle (Pelodiscus sinensis) revealed that the X and Y chromosomes of S. triporcatus have homology with P. sinensis chromosome 6, which corresponds to the chicken Z chromosome. We cloned cDNA fragments of S. triporcatus homologs of 16 chicken Z-linked genes and mapped them to S. triporcatus and S. salvinii chromosomes using fluorescence in situ hybridization. Sixteen genes were localized to the X and Y long arms in the same order in both species. The orders were also almost the same as those of the ostrich (Struthio camelus) Z chromosome, which retains the primitive state of the avian ancestral Z chromosome. These results strongly suggest that the X and Y chromosomes of Staurotypus turtles are at a very early stage of sex chromosome differentiation, and that these chromosomes and the avian ZW chromosomes share the same origin. Nonetheless, the turtles and birds acquired different systems of heterogametic sex determination during their evolution.

  20. The Staurotypus turtles and aves share the same origin of sex chromosomes but evolved different types of heterogametic sex determination.

    Directory of Open Access Journals (Sweden)

    Taiki Kawagoshi

    Full Text Available Reptiles have a wide diversity of sex-determining mechanisms and types of sex chromosomes. Turtles exhibit temperature-dependent sex determination and genotypic sex determination, with male heterogametic (XX/XY and female heterogametic (ZZ/ZW sex chromosomes. Identification of sex chromosomes in many turtle species and their comparative genomic analysis are of great significance to understand the evolutionary processes of sex determination and sex chromosome differentiation in Testudines. The Mexican giant musk turtle (Staurotypus triporcatus, Kinosternidae, Testudines and the giant musk turtle (Staurotypus salvinii have heteromorphic XY sex chromosomes with a low degree of morphological differentiation; however, their origin and linkage group are still unknown. Cross-species chromosome painting with chromosome-specific DNA from Chinese soft-shelled turtle (Pelodiscus sinensis revealed that the X and Y chromosomes of S. triporcatus have homology with P. sinensis chromosome 6, which corresponds to the chicken Z chromosome. We cloned cDNA fragments of S. triporcatus homologs of 16 chicken Z-linked genes and mapped them to S. triporcatus and S. salvinii chromosomes using fluorescence in situ hybridization. Sixteen genes were localized to the X and Y long arms in the same order in both species. The orders were also almost the same as those of the ostrich (Struthio camelus Z chromosome, which retains the primitive state of the avian ancestral Z chromosome. These results strongly suggest that the X and Y chromosomes of Staurotypus turtles are at a very early stage of sex chromosome differentiation, and that these chromosomes and the avian ZW chromosomes share the same origin. Nonetheless, the turtles and birds acquired different systems of heterogametic sex determination during their evolution.

  1. Chromosomal rearrangement interferes with meiotic X chromosome inactivation

    OpenAIRE

    Homolka, David; Ivanek, Robert; Capkova, Jana; Jansa, Petr; Forejt, Jiri

    2007-01-01

    Heterozygosity for certain mouse and human chromosomal rearrangements is characterized by the incomplete meiotic synapsis of rearranged chromosomes, by their colocalization with the XY body in primary spermatocytes, and by male-limited sterility. Previously, we argued that such X–autosomal associations could interfere with meiotic sex chromosome inactivation. Recently, supporting evidence has reported modifications of histones in rearranged chromosomes by a process called the meiotic silencin...

  2. Isolation of cosmid and cDNA clones in the region surrounding the BTK gene at Xq21.3-q22

    Energy Technology Data Exchange (ETDEWEB)

    Vorechovsky, I.; Zhou, J.N.; Hammarstroem, L. [Karolinska Institute, Huddinge (Sweden)] [and others

    1994-06-01

    A regional physical and transcription map involving yeast artificial chromosomes (YACs), cosmids, and cDNAs has been constructed for Xq21.3-q22 around the gene BTK (formerly atk or BPK) defective in X-linked agammaglobulinemia (XLA). With a positional cloning strategy employing direct cDNA selection, novel cDNAs were found to cluster in the region of approximately 100 kb flanking the XLA and {alpha}-galactosidase A loci. While these widely expressed transcripts are in the area known to contain CpG islands, a less evolutionarily conserved gene, located more than 130 kb distal of DXS178, maps to cosmid clones that could not be digested with rare-cutting restriction enzymes. The presence of transcribed sequences flanking the BTK allowed investigation of their involvement in complex XLA phenotypes. Southern blot analysis using cDNA clones isolated from this region permitted exclusion of a contiguous deletion syndrome as an underlying defect in three patients with XLA and associated growth hormone deficiency. A single XLA patient with torsion dystonia and cosegregating X-linked deafness has been found with a deletion in the 3{prime} part of BTK extending centromerically into the flanking expressed sequence DXS1274E. This suggests a possible involvement of the DXS1274E in this phenotype. The GenBank accession numbers for novel cDNA sequences are as follows: DXS1269E (L20773), DXS1271E (UO1923), DXS1273E (UO1925), and DXS1274E (UO1922). 51 refs., 4 figs., 1 tab.

  3. Cattle mammary bioreactor generated by a novel procedure of transgenic cloning for large-scale production of functional human lactoferrin.

    Directory of Open Access Journals (Sweden)

    Penghua Yang

    Full Text Available Large-scale production of biopharmaceuticals by current bioreactor techniques is limited by low transgenic efficiency and low expression of foreign proteins. In general, a bacterial artificial chromosome (BAC harboring most regulatory elements is capable of overcoming the limitations, but transferring BAC into donor cells is difficult. We describe here the use of cattle mammary bioreactor to produce functional recombinant human lactoferrin (rhLF by a novel procedure of transgenic cloning, which employs microinjection to generate transgenic somatic cells as donor cells. Bovine fibroblast cells were co-microinjected for the first time with a 150-kb BAC carrying the human lactoferrin gene and a marker gene. The resulting transfection efficiency of up to 15.79 x 10(-2 percent was notably higher than that of electroporation and lipofection. Following somatic cell nuclear transfer, we obtained two transgenic cows that secreted rhLF at high levels, 2.5 g/l and 3.4 g/l, respectively. The rhLF had a similar pattern of glycosylation and proteolytic susceptibility as the natural human counterpart. Biochemical analysis revealed that the iron-binding and releasing properties of rhLF were identical to that of native hLF. Importantly, an antibacterial experiment further demonstrated that rhLF was functional. Our results indicate that co-microinjection with a BAC and a marker gene into donor cells for somatic cell cloning indeed improves transgenic efficiency. Moreover, the cattle mammary bioreactors generated with this novel procedure produce functional rhLF on an industrial scale.

  4. Chromatin Folding, Fragile Sites, and Chromosome Aberrations Induced by Low- and High- LET Radiation

    Science.gov (United States)

    Zhang, Ye; Cox, Bradley; Asaithamby, Aroumougame; Chen, David J.; Wu, Honglu

    2013-01-01

    We previously demonstrated non-random distributions of breaks involved in chromosome aberrations induced by low- and high-LET radiation. To investigate the factors contributing to the break point distribution in radiation-induced chromosome aberrations, human epithelial cells were fixed in G1 phase. Interphase chromosomes were hybridized with a multicolor banding in situ hybridization (mBAND) probe for chromosome 3 which distinguishes six regions of the chromosome in separate colors. After the images were captured with a laser scanning confocal microscope, the 3-dimensional structure of interphase chromosome 3 was reconstructed at multimega base pair scale. Specific locations of the chromosome, in interphase, were also analyzed with bacterial artificial chromosome (BAC) probes. Both mBAND and BAC studies revealed non-random folding of chromatin in interphase, and suggested association of interphase chromatin folding to the radiation-induced chromosome aberration hotspots. We further investigated the distribution of genes, as well as the distribution of breaks found in tumor cells. Comparisons of these distributions to the radiation hotspots showed that some of the radiation hotspots coincide with the frequent breaks found in solid tumors and with the fragile sites for other environmental toxins. Our results suggest that multiple factors, including the chromatin structure and the gene distribution, can contribute to radiation-induced chromosome aberrations.

  5. B lineage acute lymphoblastic leukemia transformation in a child with juvenile myelomonocytic leukemia, type 1 neurofibromatosis and monosomy of chromosome 7. Possible implications in the leukemogenesis

    DEFF Research Database (Denmark)

    Scrideli, Carlos Alberto; Baruffi, Marcelo Razera; Rogatto, Silvia Regina

    2003-01-01

    diagnosis of JMML and ALL, suggesting that both neoplasias may have evolved from the same clone. Our results support the theory that JMML may derive from pluripotential cells and that the occurrence of monosomy of chromosome 7 within a clone of cells having an aberrant neurofibromatosis type 1 (NF1) gene...

  6. The M26 hotspot of Schizosaccharomyces pombe stimulates meiotic ectopic recombination and chromosomal rearrangements.

    OpenAIRE

    Virgin, J B; Bailey, J P

    1998-01-01

    Homologous recombination is increased during meiosis between DNA sequences at the same chromosomal position (allelic recombination) and at different chromosomal positions (ectopic recombination). Recombination hotspots are important elements in controlling meiotic allelic recombination. We have used artificially dispersed copies of the ade6 gene in Schizosaccharomyces pombe to study hotspot activity in meiotic ectopic recombination. Ectopic recombination was reduced 10-1000-fold relative to a...

  7. Systematic analysis of human protein complexes identifies chromosome segregation proteins.

    Science.gov (United States)

    Hutchins, James R A; Toyoda, Yusuke; Hegemann, Björn; Poser, Ina; Hériché, Jean-Karim; Sykora, Martina M; Augsburg, Martina; Hudecz, Otto; Buschhorn, Bettina A; Bulkescher, Jutta; Conrad, Christian; Comartin, David; Schleiffer, Alexander; Sarov, Mihail; Pozniakovsky, Andrei; Slabicki, Mikolaj Michal; Schloissnig, Siegfried; Steinmacher, Ines; Leuschner, Marit; Ssykor, Andrea; Lawo, Steffen; Pelletier, Laurence; Stark, Holger; Nasmyth, Kim; Ellenberg, Jan; Durbin, Richard; Buchholz, Frank; Mechtler, Karl; Hyman, Anthony A; Peters, Jan-Michael

    2010-04-30

    Chromosome segregation and cell division are essential, highly ordered processes that depend on numerous protein complexes. Results from recent RNA interference screens indicate that the identity and composition of these protein complexes is incompletely understood. Using gene tagging on bacterial artificial chromosomes, protein localization, and tandem-affinity purification-mass spectrometry, the MitoCheck consortium has analyzed about 100 human protein complexes, many of which had not or had only incompletely been characterized. This work has led to the discovery of previously unknown, evolutionarily conserved subunits of the anaphase-promoting complex and the gamma-tubulin ring complex--large complexes that are essential for spindle assembly and chromosome segregation. The approaches we describe here are generally applicable to high-throughput follow-up analyses of phenotypic screens in mammalian cells.

  8. Isolation of 24 novel cDNA fragments from microdis—sected human chromosome band

    Institute of Scientific and Technical Information of China (English)

    ZHANGMIN; LONGYU; 等

    1998-01-01

    The strategy of isolating the band0specific expression fragments from a probe pool generated by human chromosome microdissection was reported.A chromosome 14q 24.3 band-specific single copy DNA pool was constructed based on this probe pool.Using total DNA of the pool as probe to hybridize the human marrow cDNA library,68 primary positive clones were selected from 5×105 cDNA clones.Among these primary clones,32 secondary clones were obtained after second-round screening and designed as cFD14-1-32.Finally,24 band-specific expression fragments were identified from these 32 positive clones by DNA hybridization.Those band-specific clones can hybridize to both 14q24.3 DNA and human genomic DNA but cann't hybridize to 17q11-12 DNA,Partial sequences of 13 fragments of them were sequenced and idenfified as novel cDNA sequences,and these sequences were proved to have some homology with known genes in NCBI database.Analysis of expression spectrum of cFD 14-1 suggested that the cDNA fragments thus obtained should be used to isolate the genes can not been cloned in 14q24.3 region.

  9. More Genetic Engineering With Cloned Hemoglobin Genes

    Science.gov (United States)

    Bailey, James E.

    1992-01-01

    Cells modified to enhance growth and production of proteins. Method for enhancing both growth of micro-organisms in vitro and production of various proteins or metalbolites in these micro-organisms provides for incorporation of selected chromosomal or extrachormosomal deoxyribonucleic acid (DNA) sequences into micro-organisms from other cells or from artificial sources. Incorporated DNA includes parts encoding desired product(s) or characteristic(s) of cells and parts that control expression of productor characteristic-encoding parts in response to variations in environment. Extended method enables increased research into growth of organisms in oxygen-poor environments. Industrial applications found in enhancement of processing steps requiring oxygen in fermentation, enzymatic degradation, treatment of wastes containing toxic chemicals, brewing, and some oxidative chemical reactions.

  10. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli;

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... chromosomes that results in formation of derivative chromosomes with a mixed DNA sequence. The method currently used for their detection is Fluorescent In Situ Hybridization, which requires a use of expensive, fluorescently labeled probes that target the derivative chromosomes. We present here a double...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...

  11. Chromosome Variations And Human Behavior

    Science.gov (United States)

    Soudek, D.

    1974-01-01

    Article focused on the science of cytogenetics, which studied the transmission of the units of heredity called chromosomes, and considered the advantage of proper diagnosis of genetic diseases, treated on the chromosomal level. (Author/RK)

  12. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B;

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation...

  13. Chromosomes, cancer and radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Samouhos, E.

    1983-08-01

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available.

  14. The Y Chromosome

    Science.gov (United States)

    Offner, Susan

    2010-01-01

    The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

  15. Why Chromosome Palindromes?

    Directory of Open Access Journals (Sweden)

    Esther Betrán

    2012-01-01

    Full Text Available We look at sex-limited chromosome (Y or W evolution with particular emphasis on the importance of palindromes. Y chromosome palindromes consist of inverted duplicates that allow for local recombination in an otherwise nonrecombining chromosome. Since palindromes enable intrachromosomal gene conversion that can help eliminate deleterious mutations, they are often highlighted as mechanisms to protect against Y degeneration. However, the adaptive significance of recombination resides in its ability to decouple the evolutionary fates of linked mutations, leading to both a decrease in degeneration rate and an increase in adaptation rate. Our paper emphasizes the latter, that palindromes may exist to accelerate adaptation by increasing the potential targets and fixation rates of incoming beneficial mutations. This hypothesis helps reconcile two enigmatic features of the “palindromes as protectors” view: (1 genes that are not located in palindromes have been retained under purifying selection for tens of millions of years, and (2 under models that only consider deleterious mutations, gene conversion benefits duplicate gene maintenance but not initial fixation. We conclude by looking at ways to test the hypothesis that palindromes enhance the rate of adaptive evolution of Y-linked genes and whether this effect can be extended to palindromes on other chromosomes.

  16. Photoinhibition of photosynthesis in needles of two cypress (Cupressus sempervirens) clones.

    Science.gov (United States)

    La Porta, Nicola; Bertamini, Massimo; Nedunchezhian, Namachevayam; Raddi, Paolo; Muthuchelian, Krishnasamy

    2005-08-01

    Photoinhibition of photosynthesis and photosynthetic recovery were studied in detached needles of cypress (Cupressus sempervirens L.) Clones 52 and 30 under controlled conditions of high irradiation (about 1900 micromol m(-2) s(-1) for 60 min; HL treatment), followed by 60 min in darkness. The degree of photoinhibition was determined based on the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm), which is a measure of the potential efficiency of photosystem II (PSII), and on electron transport measurements. The Fv/Fm ratio declined in needles of both clones in response to the HL treatment. Minimal fluorescence (Fo) increased in HL-treated needles of both clones. The HL treatment decreased rates of whole-chain and PSII activity of isolated thylakoids more in Clone 52 than in Clone 30. In needles of both clones, PSI activity was less sensitive to photoinhibition than PSII activity. In the subsequent 60-min dark incubation, fast recovery was observed in needles of both clones, with PSII efficiencies reaching similar values to those in non-photoinhibited needles. The artificial exogenous electron donors diphenyl carbazide (DPC), hydroxylamine (NH2OH) and manganese chloride (MnCl2) failed to restore the HL-induced loss of PSII activity in needles of Clone 30, whereas DPC and NH2OH significantly restored PSII activity in photoinhibited needles of Clone 52. Quantification of the PSII reaction center protein D1 and the 33-kDa protein of the water-splitting complex following HL treatment of needles revealed pronounced differences between Clone 52 and Clone 30. The large decrease in PSII activity in HL-treated needles was caused by the marked loss of D1 protein and 33-kDa protein in Clone 30 and Clone 52, respectively.

  17. Ethical issues in animal cloning.

    Science.gov (United States)

    Fiester, Autumn

    2005-01-01

    The issue of human reproductive cloning has recently received a great deal attention in public discourse. Bioethicists, policy makers, and the media have been quick to identify the key ethical issues involved in human reproductive cloning and to argue, almost unanimously, for an international ban on such attempts. Meanwhile, scientists have proceeded with extensive research agendas in the cloning of animals. Despite this research, there has been little public discussion of the ethical issues raised by animal cloning projects. Polling data show that the public is decidedly against the cloning of animals. To understand the public's reaction and fill the void of reasoned debate about the issue, we need to review the possible objections to animal cloning and assess the merits of the anti-animal cloning stance. Some objections to animal cloning (e.g., the impact of cloning on the population of unwanted animals) can be easily addressed, while others (e.g., the health of cloned animals) require more serious attention by the public and policy makers.

  18. Chromosomal mapping of the structural gene coding for the mouse cell adhesion molecule uvomorulin

    Energy Technology Data Exchange (ETDEWEB)

    Eistetter, H.R.; Adolph, S.; Ringwald, M.; Simon-Chazottes, D.; Schuh, R.; Guenet, J.L.; Kemler, R. (Max-Planck-Gesellschaft, Tuebingen (West Germany))

    1988-05-01

    The gene coding for the mouse cell adhesion molecule uvomorulin has been mapped to chromosome 8. Uvomorulin cDNA clone F5H3 identified restriction fragment length polymorphisms in Southern blots of genomic DNA from mouse species Mus musculus domesticus and Mus spretus. By analyzing the segregation pattern of the gene in 75 offspring from an interspecific backcross a single genetic locus, Um, was defined on chromosome 8. Recombination frequency between Um and the co-segregating loci serum esterase 1 (Es-1) and tyrosine aminotransferase (Tat) places Um about 14 centimorgan (cM) distal to Es-1, and 5 cM proximal to Tat. In situ hybridization of uvomorulin ({sup 3}H)cDNA to mouse metaphase chromosomes located the Um locus close to the distal end of chromosome 8 (bands C3-E1). Since uvomorulin is evolutionarily highly conserved, its chromosomal assignment adds an important marker to the mouse genetic map.

  19. Telomere dysfunction and chromosome instability

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, John P., E-mail: jmurnane@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, 2340 Sutter Street, San Francisco, CA 94143-1331 (United States)

    2012-02-01

    The ends of chromosomes are composed of a short repeat sequence and associated proteins that together form a cap, called a telomere, that keeps the ends from appearing as double-strand breaks (DSBs) and prevents chromosome fusion. The loss of telomeric repeat sequences or deficiencies in telomeric proteins can result in chromosome fusion and lead to chromosome instability. The similarity between chromosome rearrangements resulting from telomere loss and those found in cancer cells implicates telomere loss as an important mechanism for the chromosome instability contributing to human cancer. Telomere loss in cancer cells can occur through gradual shortening due to insufficient telomerase, the protein that maintains telomeres. However, cancer cells often have a high rate of spontaneous telomere loss despite the expression of telomerase, which has been proposed to result from a combination of oncogene-mediated replication stress and a deficiency in DSB repair in telomeric regions. Chromosome fusion in mammalian cells primarily involves nonhomologous end joining (NHEJ), which is the major form of DSB repair. Chromosome fusion initiates chromosome instability involving breakage-fusion-bridge (B/F/B) cycles, in which dicentric chromosomes form bridges and break as the cell attempts to divide, repeating the process in subsequent cell cycles. Fusion between sister chromatids results in large inverted repeats on the end of the chromosome, which amplify further following additional B/F/B cycles. B/F/B cycles continue until the chromosome acquires a new telomere, most often by translocation of the end of another chromosome. The instability is not confined to a chromosome that loses its telomere, because the instability is transferred to the chromosome donating a translocation. Moreover, the amplified regions are unstable and form extrachromosomal DNA that can reintegrate at new locations. Knowledge concerning the factors promoting telomere loss and its consequences is

  20. [Dicentric Y chromosome].

    Science.gov (United States)

    Abdelmoula, N Bouayed; Amouri, A

    2005-01-01

    Dicentric Y chromosomes are the most common Y structural abnormalities and their influence on gonadal and somatic development is extremely variable. Here, we report the third comprehensive review of the literature concerning dicentric Y chromosomes reported since 1994. We find 78 new cases for which molecular studies (PCR or FISH) have been widely applied to investigate SRY (68% of cases), GBY, ZFY, RFS4Y, GCY and different genes at AZF region. For dic(Yq), all cases (n = 20) were mosaic for 45,X and 4 of them were also mosaic for a 46,XY cell line. When breakpoints were available (15/20 cases), they were in Yp11. 50% of cases were phenotypic female and 20% phenotypic male while 20% of cases were reported with gonadal dysgenesis. Gonadal histology was defined in 8 cases but only in one case, gonadal tissu was genetically investigated because of gonadoblastoma. For dic(Yp) (n = 55), mosaicism concerned only 45,X cell line and was found in 50 cases while the remainder five cases were homogeneous. When breakpoints were available, it was at Yq11 in 50 cases and at Yq12 in two cases. 54% of cases were phenotypic female, 26% were phenotypic male and 18% were associated with genitalia ambiguous. SRY was analyzed in 33 cases, sequenced in 9 cases and was muted in only one case. Gonads were histologically explored in 34 cases and genetically investigated in 8 cases. Gonadoblastoma was found in only two cases. Through this review, it seems that phenotype-genotype correlations are still not possible and that homogeneous studies of dic(Y) in more patients using molecular tools for structural characterization of the rearranged Y chromosome and assessment of mosaicism in many organs are necessary to clarify the basis of the phenotypic heterogeneity of dicentric Y chromosomes and then to help phenotypic prediction of such chromosome rearrangement.

  1. Reprogramming to pluripotency can conceal somatic cell chromosomal instability.

    Directory of Open Access Journals (Sweden)

    Masakazu Hamada

    Full Text Available The discovery that somatic cells are reprogrammable to pluripotency by ectopic expression of a small subset of transcription factors has created great potential for the development of broadly applicable stem-cell-based therapies. One of the concerns regarding the safe use of induced pluripotent stem cells (iPSCs in therapeutic applications is loss of genomic integrity, a hallmark of various human conditions and diseases, including cancer. Structural chromosome defects such as short telomeres and double-strand breaks are known to limit reprogramming of somatic cells into iPSCs, but whether defects that cause whole-chromosome instability (W-CIN preclude reprogramming is unknown. Here we demonstrate, using aneuploidy-prone mouse embryonic fibroblasts (MEFs in which chromosome missegregation is driven by BubR1 or RanBP2 insufficiency, that W-CIN is not a barrier to reprogramming. Unexpectedly, the two W-CIN defects had contrasting effects on iPSC genomic integrity, with BubR1 hypomorphic MEFs almost exclusively yielding aneuploid iPSC clones and RanBP2 hypomorphic MEFs karyotypically normal iPSC clones. Moreover, BubR1-insufficient iPSC clones were karyotypically unstable, whereas RanBP2-insufficient iPSC clones were rather stable. These findings suggest that aneuploid cells can be selected for or against during reprogramming depending on the W-CIN gene defect and present the novel concept that somatic cell W-CIN can be concealed in the pluripotent state. Thus, karyotypic analysis of somatic cells of origin in addition to iPSC lines is necessary for safe application of reprogramming technology.

  2. Artificial life and life artificialization in Tron

    Directory of Open Access Journals (Sweden)

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  3. TP53-dependent chromosome instability is associated with transient reductions in telomere length in immortal telomerase-positive cell lines

    Science.gov (United States)

    Schwartz, J. L.; Jordan, R.; Liber, H.; Murnane, J. P.; Evans, H. H.

    2001-01-01

    Telomere shortening in telomerase-negative somatic cells leads to the activation of the TP53 protein and the elimination of potentially unstable cells. We examined the effect of TP53 gene expression on both telomere metabolism and chromosome stability in immortal, telomerase-positive cell lines. Telomere length, telomerase activity, and chromosome instability were measured in multiple clones isolated from three related human B-lymphoblast cell lines that vary in TP53 expression; TK6 cells express wild-type TP53, WTK1 cells overexpress a mutant form of TP53, and NH32 cells express no TP53 protein. Clonal variations in both telomere length and chromosome stability were observed, and shorter telomeres were associated with higher levels of chromosome instability. The shortest telomeres were found in WTK1- and NH32-derived cells, and these cells had 5- to 10-fold higher levels of chromosome instability. The primary marker of instability was the presence of dicentric chromosomes. Aneuploidy and other stable chromosome alterations were also found in clones showing high levels of dicentrics. Polyploidy was found only in WTK1-derived cells. Both telomere length and chromosome instability fluctuated in the different cell populations with time in culture, presumably as unstable cells and cells with short telomeres were eliminated from the growing population. Our results suggest that transient reductions in telomere lengths may be common in immortal cell lines and that these alterations in telomere metabolism can have a profound effect on chromosome stability. Copyright 2000 Wiley-Liss, Inc.

  4. Dynamics of X Chromosome Inactivation

    NARCIS (Netherlands)

    F. Loos (Friedemann)

    2015-01-01

    markdownabstract__Abstract__ Dosage compensation evolved to account for the difference in expression of sex chromosome-linked genes. In mammals dosage compensation is achieved by inactivation of one X chromosome during early female embryogenesis in a process called X chromosome inactivation (XCI).

  5. To clone or not to clone--whither the law?

    Science.gov (United States)

    Lupton, M L

    1999-01-01

    The cloning of Dolly the lamb from adult cells by scientists at the Roslin Laboratories near Edinburgh in February 1997 has startled the world because it now opens the way to clone adult human beings. The reaction to Ian Wilmut's breakthrough has been instant and largely negative. Bills were rushed into both the US Senate and House of Representatives aimed at banning the cloning of human beings. Human cloning is premature at this stage, but there are many positive spin-offs of cloning in the field of genetic engineering, such as the production of human proteins such as blood clotting factors which aid in healing wounds. Progress by means of cloning can also be made into devising a cure for Parkinson's Disease amongst others. No lesser ethicist than John C. Fletcher of the University of Virginia foresees circumstances in which human cloning is acceptable e.g. to enable a couple to replace a dying child, to enable a couple, one of whom is infertile, to clone a child from either partner. Extensive regulation of cloning by the law is inevitable but, in doing so, the legislation should be careful not to outlaw research in this area which could be beneficial to mankind.

  6. Physical mapping of the split hand/split foot (SHSF) locus on chromosome 7 reveals a relationship between SHSF and the syndromic ectrodactylies

    Energy Technology Data Exchange (ETDEWEB)

    Poorkaj, P.; Nunes, M.E.; Geshuri, D. [Univ. of Washington, Seattle, WA (United States)] [and others

    1994-09-01

    Split hand/split foot (also knows as ectrodactyly) is a human developmental malformation characterized by missing digits and claw-like extremities. An autosomal dominant form of this disorder has been mapped to 7q21.3-q22.1 on the basis of SHSF-associated chromosomal rearrangements: this locus has been designated SHFD1. We have constructed a physical map of the SHFD1 region that consists of contiguous yeast artificial chromosome clones and spans approximately 8 Mb. Somatic cell hybrid and fluorescent in situ hybridization analyses were used to define SHSF-associated chromosomal breakpoints in fourteen patients. A critical interval of about 1 Mb was established for SHFD1 by analysis of six patients with deletions. Translocation and inversion breakpoints in seven other patients were found to localize within a 500-700 kb interval within the critical region. Several candidate genes including DLX5 and DLX6 (members of the Drosophilia Distal-less homeobox-containing gene family) localize to this region. At least four of these genes are expressed in the developing mouse limb bud. Of particular interest is the observation that 8 of the 14 patients studied have syndromic ectrodactyly, which is characterized by the association of SHSF with a variety of other anomalies including cleft lip/palate, ectodermal dysplasia, and renal anomalies. Thus, these data implicate a single gene or cluster of genes at the SHFD1 locus in a wide range of developmental processes and serve to establish a molecular genetic relationship between simple SHSF and a broad group of human birth defects.

  7. Chromosomal breakpoints characterization of two supernumerary ring chromosomes 20.

    Science.gov (United States)

    Guediche, N; Brisset, S; Benichou, J-J; Guérin, N; Mabboux, P; Maurin, M-L; Bas, C; Laroudie, M; Picone, O; Goldszmidt, D; Prévot, S; Labrune, P; Tachdjian, G

    2010-02-01

    The occurrence of an additional ring chromosome 20 is a rare chromosome abnormality, and no common phenotype has been yet described. We report on two new patients presenting with a supernumerary ring chromosome 20 both prenatally diagnosed. The first presented with intrauterine growth retardation and some craniofacial dysmorphism, and the second case had a normal phenotype except for obesity. Conventional cytogenetic studies showed for each patient a small supernumerary marker chromosome (SMC). Using fluorescence in situ hybridization, these SMCs corresponded to ring chromosomes 20 including a part of short and long arms of chromosome 20. Detailed molecular cytogenetic characterization showed different breakpoints (20p11.23 and 20q11.23 for Patient 1 and 20p11.21 and 20q11.21 for Patient 2) and sizes of the two ring chromosomes 20 (13.6 Mb for case 1 and 4.8 Mb for case 2). Review of the 13 case reports of an extra r(20) ascertained postnatally (8 cases) and prenatally (5 cases) showed varying degrees of phenotypic abnormalities. We document a detailed molecular cytogenetic chromosomal breakpoints characterization of two cases of supernumerary ring chromosomes 20. These results emphasize the need to characterize precisely chromosomal breakpoints of supernumerary ring chromosomes 20 in order to establish genotype-phenotype correlation. This report may be helpful for prediction of natural history and outcome, particularly in prenatal diagnosis.

  8. Chromosomal assignment of canine THADA gene to CFA 10q25

    Directory of Open Access Journals (Sweden)

    Dolf Gaudenz

    2008-06-01

    Full Text Available Abstract Background Chromosomal translocations affecting the chromosome 2p21 cluster in a 450 kb breakpoint region are frequently observed in human benign thyroid adenomas. THADA (thyroid adenoma associated was identified as the affected gene within this breakpoint region. In contrast to man tumours of the thyroid gland of dogs (Canis lupus familiaris constitute mainly as follicular cell carcinomas, with malignant thyroid tumours being more frequent than benign thyroid adenomas. In order to elucidate if the THADA gene is also a target of chromosomal rearrangements in thyroid adenomas of the dog we have physically mapped the canine THADA gene to canine chromosome 10. A PCR was established to screen a canine genome library for a BAC clone containing the gene sequence of canine THADA. Further PCR reactions were done using the identified BAC clone as a template in order to verify the corresponding PCR product by sequencing. Canine whole blood was incubated with colcemid in order to arrest the cultured cells in metaphases. The verified BAC DNA was digoxigenin labeled and used as a probe in fluorescence in situ hybridization (FISH. Ten well spread metaphases were examined indicating a signal on canine chromosome 10 on both chromatids. A detailed fine mapping was performed indicating the canine THADA gene locus on the q-arm of chromosome 10. Results The canine THADA gene locus was mapped on chromosome 10q25. Our mapping results obtained in this study following the previously described nomenclature for the canine karyotype. Conclusion We analysed whether the THADA gene locus is a hotspot of canine chromosomal rearrangements in canine neoplastic lesions of the thyroid and in addition might play a role as a candidate gene for a possible malignant transformation of canine thyroid adenomas. Although the available cytogenetic data of canine thyroid adenomas are still insufficient the chromosomal region to which the canine THADA has been mapped seems to be no

  9. Familial complex chromosomal rearrangement resulting in a recombinant chromosome.

    Science.gov (United States)

    Berend, Sue Ann; Bodamer, Olaf A F; Shapira, Stuart K; Shaffer, Lisa G; Bacino, Carlos A

    2002-05-15

    Familial complex chromosomal rearrangements (CCRs) are rare and tend to involve fewer breakpoints and fewer chromosomes than CCRs that are de novo in origin. We report on a CCR identified in a child with congenital heart disease and dysmorphic features. Initially, the child's karyotype was thought to involve a straightforward three-way translocation between chromosomes 3, 8, and 16. However, after analyzing the mother's chromosomes, the mother was found to have a more complex rearrangement that resulted in a recombinant chromosome in the child. The mother's karyotype included an inverted chromosome 2 and multiple translocations involving chromosomes 3, 5, 8, and 16. No evidence of deletion or duplication that could account for the clinical findings in the child was identified.

  10. The Relationship Between Spontaneous Telomere Loss and Chromosome Instability in a Human Tumor Cell Line

    Directory of Open Access Journals (Sweden)

    Bijan Fouladi

    2000-01-01

    Full Text Available Chromosome instability plays an important role in cancer by promoting the alterations in the genome required for tumor cell progression. The loss of telomeres that protect the ends of chromosomes and prevent chromosome fusion has been proposed as one mechanism for chromosome instability in cancer cells, however, there is little direct evidence to support this hypothesis. To investigate the relationship between spontaneous telomere loss and chromosome instability in human cancer cells, clones of the EJ-30 tumor cell line were isolated in which a herpes simplex virus thymidine kinase (HSV-tk gene was integrated immediately adjacent to a telomere. Selection for HSV-tkdeficient cells with ganciclovir demonstrated a high rate of loss of the end these "marked" chromosomes (10-4 events/cell per generation. DNA sequence and cytogenetic analysis suggests that the loss of function of the HSV-tk gene most often involves telomere loss, sister chromatid fusion, and prolonged periods of chromosome instability. In some HSV-tk-deficient cells, telomeric repeat sequences were added on to the end of the truncated HSV-tk gene at a new location, whereas in others, no telomere was detected on the end of the marked chromosome. These results suggest that spontaneous telomere loss is a mechanism for chromosome instability in human cancer cells.

  11. Lessons learned from cloning dogs.

    Science.gov (United States)

    Kim, M J; Oh, H J; Kim, G A; Park, J E; Park, E J; Jang, G; Ra, J C; Kang, S K; Lee, B C

    2012-08-01

    The aim of this article is to review dog cloning research and to suggest its applications based on a discussion about the normality of cloned dogs. Somatic cell nuclear transfer was successfully used for production of viable cloned puppies despite limited understanding of in vitro dog embryo production. Cloned dogs have similar growth characteristics to those born from natural fertilization, with no evidence of serious adverse effects. The offspring of cloned dogs also have similar growth performance and health to those of naturally bred puppies. Therefore, cloning in domestic dogs can be applied as an assisted reproductive technique to conserve endangered species, to treat sterile canids or aged dogs, to improve reproductive performance of valuable individuals and to generate disease model animals.

  12. Duplication and loss of chromosome 21 in two children with Down Syndrome and acute leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Rogan, P.K.; Close, P.; Seip, J.R. [Pennsylvania State Univ. College of Medicine, Hershey, PA (United States)] [and others

    1994-09-01

    Acute leukemia in patients with Trisomy 21 (Down Syndrome; DS) may often result in additional karyotypic changes in the number or structure of chromosome 21. We present two DS patients whose immunoblast karyotypes were associated with changes in chromosome 21 ploidy. Patient L.E. developed acute lymphocytic leukemia concomitant with the loss of a single copy of chromosome 21. Trisomy 21 in this individual was due to maternal meiosis I nondisjunction. A recombination event resulted in reduction of maternal alleles to homozygosity distal to D21S167. Loss of the paternal chromosomes in the leukemia clone produced uniparental maternal disomy with isodisomy over a 25cM interval. This could, in theory, permit the unopposed expression of one or more homozygous recessive maternal tumor-associated genes, thus providing an explanation for leukemogenesis in this patient. Patient E.H. was diagnosed with acute monoblastic leukemia and consistently displayed tetrasomy 21 in the blast cell population. The DS karyotype probably arose from a mitotic error in which the paternal chromosome was duplicated. DNA polymorphism analysis indicated that the additional chromosome in the leukemia clone was of maternal origin. The presence of equal numbers of maternal and paternal chromosomes in the tetraploid blast clone would not appear to be consistent with the expression of a mutant tumor suppressor gene in this patient. Although tetrasomy 21 could be a non-specific karyotypic abnormality unrelated to leukemogenesis, it is possible that monoblastic leukemia may be a consequence of increased expression of one or more genes on this chromosome.

  13. Screening and sequencing of candidate genes in Chinese merino sheep 55L9 BAC clone%中国美利奴绵羊55L9BAC克隆基因的筛选与序列的初步分析

    Institute of Scientific and Technical Information of China (English)

    董慧芹; 李峰; 白大章; 杨晓亮; 陈芳; 高剑峰

    2011-01-01

    Sheep 55L9 BAC (bacterial artificial chromosomes) clones was used to prepare radioactive probes. The probes were used to screen the immune-related gene from Chinese merino cDNA library through phage in situ hybridization.The isolated candidate positive cDNA clones were sequenced and analyzed. Twelve candidate positive clones were screened out, of which 8 separate sequences obtained by sequencing and blasting may be immune-related genes of sheep. Two genes in the 8 separate sequences were located on the 55L9 BAC.%利用绵羊55L9 BAC(细菌人造染色体)克隆制备探针,采用噬菌斑原位杂交方法,从中国美利奴细毛羊cDNA文库中筛选与免疫相关的基因,并对筛选得到的候选基因进行测序及软件分析.初步筛出12个候选阳性克隆.经过测序和比对,推测有8个独立的序列可能与绵羊的免疫及疾病相关,其中2个基因可以在已提交的BAC序列中定位.

  14. Onion artificial muscles

    Science.gov (United States)

    Chen, Chien-Chun; Shih, Wen-Pin; Chang, Pei-Zen; Lai, Hsi-Mei; Chang, Shing-Yun; Huang, Pin-Chun; Jeng, Huai-An

    2015-05-01

    Artificial muscles are soft actuators with the capability of either bending or contraction/elongation subjected to external stimulation. However, there are currently no artificial muscles that can accomplish these actions simultaneously. We found that the single layered, latticed microstructure of onion epidermal cells after acid treatment became elastic and could simultaneously stretch and bend when an electric field was applied. By modulating the magnitude of the voltage, the artificial muscle made of onion epidermal cells would deflect in opposing directions while either contracting or elongating. At voltages of 0-50 V, the artificial muscle elongated and had a maximum deflection of -30 μm; at voltages of 50-1000 V, the artificial muscle contracted and deflected 1.0 mm. The maximum force response is 20 μN at 1000 V.

  15. Molecular Cloning of Adenosinediphosphoribosyl Transferase.

    Science.gov (United States)

    1987-09-08

    ACCESSION NO.D,. 03261102F 2312 A~5 11. TITLE (include Securqt Classification) 0 Molecular Cloning of Adenosinediphosphoribosyl Transferase 12. PERSONAL...I’:- AFOSR.Tlt. 8 7 - 0 9 8,2 0IL * pi AFOSR- 85 -0377 PROGRESS REPORT Molecular Cloning of Adenosinediphosphoribosyl Transferase 5." Period of...Pharmacology and the Cardiovascular Research Institute September 8, 1987 .’, 5.’- "’S ". -f, AFOSR - 85 -0377 PROGRESS REPORT Molecular Cloning of

  16. Karyotyping of Chromosomes in Human Bronchial Epithelial Cells Transformed by High Energy Fe Ions

    Science.gov (United States)

    Yeshitla, Samrawit; Zhang, Ye; Park, Seongmi; Story, Michael D.; Wilson, Bobby; Wu, Honglu

    2015-01-01

    Lung cancer induced from exposures to space radiation is one of the most significant health risks for long-term space travels. Evidences show that low- and high- Linear energy transfer (LET)-induced transformation of normal human bronchial epithelial cells (HBEC) that are immortalized through the expression of Cdk4 and hTERT. The cells were exposed to gamma rays and high-energy Fe ions for the selection of transformed clones. Transformed HBEC are identified and analyzed chromosome aberrations (i.e. genomic instability) using the multi-color fluorescent in situ hybridization (mFISH), as well as the multi-banding in situ hybridization (mBAND) techniques. Our results show chromosomal translocations between different chromosomes and several of the breaks occurred in the q-arm of chromosome 3. We also identified copy number variations between the transformed and the parental HBEC regardless of the exposure conditions. We observed chromosomal aberrations in the lowand high-LET radiation-induced transformed clones and they are imperfectly different from clones obtain in spontaneous soft agar growth.

  17. Development of T. aestivum L.-H. californicum alien chromosome lines and assignment of homoeologous groups of Hordeum californicum chromosomes.

    Science.gov (United States)

    Fang, Yuhui; Yuan, Jingya; Wang, Zhangjun; Wang, Haiyan; Xiao, Jin; Yang, Zhixi; Zhang, Ruiqi; Qi, Zengjun; Xu, Weigang; Hu, Lin; Wang, Xiu-E

    2014-08-20

    Hordeum californicum (2n = 2x = 14, HH) is resistant to several wheat diseases and tolerant to lower nitrogen. In this study, a molecular karyotype of H. californicum chromosomes in the Triticum aestivum L. cv. Chinese Spring (CS)-H. californicum amphidiploid (2n = 6x = 56, AABBDDHH) was established. By genomic in situ hybridization (GISH) and multicolor fluorescent in situ hybridization (FISH) using repetitive DNA clones (pTa71, pTa794 and pSc119.2) as probes, the H. californicum chromosomes could be differentiated from each other and from the wheat chromosomes unequivocally. Based on molecular karyotype and marker analyses, 12 wheat-alien chromosome lines, including four disomic addition lines (DAH1, DAH3, DAH5 and DAH6), five telosomic addition lines (MtH7L, MtH1S, MtH1L, DtH6S and DtH6L), one multiple addition line involving H. californicum chromosome H2, one disomic substitution line (DSH4) and one translocation line (TH7S/1BL), were identified from the progenies derived from the crosses of CS-H. californicum amphidiploid with common wheat varieties. A total of 482 EST (expressed sequence tag) or SSR (simple sequence repeat) markers specific for individual H. californicum chromosomes were identified, and 47, 50, 45, 49, 21, 51 and 40 markers were assigned to chromosomes H1, H2, H3, H4, H5, H6 and H7, respectively. According to the chromosome allocation of these markers, chromosomes H2, H3, H4, H5, and H7 of H. californicum have relationship with wheat homoeologous groups 5, 2, 6, 3, and 1, and hence could be designated as 5H(c), 2H(c), 6H(c), 3H(c) and 1H(c), respectively. The chromosomes H1 and H6 were designated as 7H(c) and 4H(c), respectively, by referring to SSR markers located on rye chromosomes.

  18. NotI linking clones as a tool for joining physical and genetic maps of the human genome.

    Science.gov (United States)

    Allikmets, R L; Kashuba, V I; Pettersson, B; Gizatullin, R; Lebedeva, T; Kholodnyuk, I D; Bannikov, V M; Petrov, N; Zakharyev, V M; Winberg, G

    1994-01-15

    To study the connection among NotI linking clones, CpG islands, and genes, the sequence surrounding 143 NotI sites was determined. These NotI linking clones were isolated from human chromosome 3-specific libraries and contain an average C + G content of 65%. These clones represent sequence-tagged sites that can be positioned onto chromosome maps and used for generating a long-range NotI map of the human genome. A majority (about 90%) of these clones contain transcribed sequences, as detected by Northern blot hybridization, providing an efficient link between physical and functional (genetic) maps. The GenBank nucleotide database was searched with sequences from these NotI linking clones. For many clones, homology was found to human and other vertebrate genes. About 20 clones contained various repeats in their sequences and may represent microsatellite loci. Most of these NotI linking clones therefore represent evolutionarily conserved DNA fragments and also can be used for comparative genome mapping of other mammalian species. In addition, approximately 20% of all sequenced human CpG island-containing genes and more than 12% of all well-characterized human genes were found to possess NotI restriction sites. This is at least 2-5 times more than has been previously estimated and suggests that NotI sites have a much stronger association with genes.

  19. NotL linking clones as a tool for joining physical and genetic maps of the human genome

    Energy Technology Data Exchange (ETDEWEB)

    Allikmets, R.L.; Dean, M.; Modi, W. (DynCorp National Cancer Institute, Frederick, MD (United States)); Kholodnyuk, I.D.; Winberg, G.; Klein, G. (Karolinska Institutet, Stockholm (Sweden)); Pettersson, B.; Uhlen, M. (Royal Institute of Technology, Stockholm (Sweden)); Gizatullin, R.; Bannikov, V.M. (and others)

    1994-01-15

    To study the connection among NotI linking clones, CpG islands, and genes, the sequence surrounding 143 NotI sites was determined. These NotI linking clones were isolated from human chromosome 3-specific libraries and contain an average C + G content of 65%. These clones represent sequence-tagged sites that can be positioned onto chromosome maps and used for generating a long-range NotI map of the human genome. A majority (about 90%) of these clones contain transcribed sequences, as detected by Northern blot hybridization, providing an efficient link between physical and functional (genetic) maps. The GenBank nucleotide database was searched with sequences from these NotI linking clones. For many clones, homology was found to human and other vertebrate genes. About 20 clones contained various repeats in their sequences and may represent microsatellite loci. Most of these NotI linking clones therefore represent evolutionarily conserved DNA fragments and also can be used for comparative genome mapping of other mammalian species. In addition, approximately 20% of all sequenced human CpG island-containing genes and more than 12% of all well-characterized human genes were found to possess NotI restriction sites. This is at least 2-5 times more than has been previously estimated and suggests that NotI sites have a much stronger association with genes. 41 refs., 3 figs., 2 tabs.

  20. Chromosomal evolution of the PKD1 gene family in primates

    Directory of Open Access Journals (Sweden)

    Krawczak Michael

    2008-09-01

    Full Text Available Abstract Background The autosomal dominant polycystic kidney disease (ADPKD is mostly caused by mutations in the PKD1 (polycystic kidney disease 1 gene located in 16p13.3. Moreover, there are six pseudogenes of PKD1 that are located proximal to the master gene in 16p13.1. In contrast, no pseudogene could be detected in the mouse genome, only a single copy gene on chromosome 17. The question arises how the human situation originated phylogenetically. To address this question we applied comparative FISH-mapping of a human PKD1-containing genomic BAC clone and a PKD1-cDNA clone to chromosomes of a variety of primate species and the dog as a non-primate outgroup species. Results Comparative FISH with the PKD1-cDNA clone clearly shows that in all primate species studied distinct single signals map in subtelomeric chromosomal positions orthologous to the short arm of human chromosome 16 harbouring the master PKD1 gene. Only in human and African great apes, but not in orangutan, FISH with both BAC and cDNA clones reveals additional signal clusters located proximal of and clearly separated from the PKD1 master genes indicating the chromosomal position of PKD1 pseudogenes in 16p of these species, respectively. Indeed, this is in accordance with sequencing data in human, chimpanzee and orangutan. Apart from the master PKD1 gene, six pseudogenes are identified in both, human and chimpanzee, while only a single-copy gene is present in the whole-genome sequence of orangutan. The phylogenetic reconstruction of the PKD1-tree reveals that all human pseudogenes are closely related to the human PKD1 gene, and all chimpanzee pseudogenes are closely related to the chimpanzee PKD1 gene. However, our statistical analyses provide strong indication that gene conversion events may have occurred within the PKD1 family members of human and chimpanzee, respectively. Conclusion PKD1 must have undergone amplification very recently in hominid evolution. Duplicative

  1. Recombinant protein expression by targeting pre-selected chromosomal loci

    Directory of Open Access Journals (Sweden)

    Krömer Wolfgang

    2009-12-01

    Full Text Available Abstract Background Recombinant protein expression in mammalian cells is mostly achieved by stable integration of transgenes into the chromosomal DNA of established cell lines. The chromosomal surroundings have strong influences on the expression of transgenes. The exploitation of defined loci by targeting expression constructs with different regulatory elements is an approach to design high level expression systems. Further, this allows to evaluate the impact of chromosomal surroundings on distinct vector constructs. Results We explored antibody expression upon targeting diverse expression constructs into previously tagged loci in CHO-K1 and HEK293 cells that exhibit high reporter gene expression. These loci were selected by random transfer of reporter cassettes and subsequent screening. Both, retroviral infection and plasmid transfection with eGFP or antibody expression cassettes were employed for tagging. The tagged cell clones were screened for expression and single copy integration. Cell clones producing > 20 pg/cell in 24 hours could be identified. Selected integration sites that had been flanked with heterologous recombinase target sites (FRTs were targeted by Flp recombinase mediated cassette exchange (RMCE. The results give proof of principle for consistent protein expression upon RMCE. Upon targeting antibody expression cassettes 90-100% of all resulting cell clones showed correct integration. Antibody production was found to be highly consistent within the individual cell clones as expected from their isogenic nature. However, the nature and orientation of expression control elements revealed to be critical. The impact of different promoters was examined with the tag-and-targeting approach. For each of the chosen promoters high expression sites were identified. However, each site supported the chosen promoters to a different extent, indicating that the strength of a particular promoter is dominantly defined by its chromosomal context

  2. Chromosome 19 International Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ., Durham, NC (United States). Medical Center); Ropers, H.H. (Univ. Hospital Nijmegen, (The Netherlands). Dept. of Human Genetics); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1993-01-04

    The Second International Workshop on Human Chromosome 19 was hosted on January 25 and 26, 1992, by the Department of Human Genetics, University Hospital Nijmegen, The Netherlands, at the 'Meerdal Conference Center'. The workshop was supported by a grant from the European Community obtained through HUGO, the Dutch Research Organization (NWO) and the Muscular Dystrophy Association (MDA). Travel support for American participants was provided by the Department of Energy. The goals of this workshop were to produce genetic, physical and integrated maps of chromosome 19, to identify inconsistencies and gaps, and to discuss and exchange resources and techniques available for the completion of these maps. The second day of the meeting was largely devoted to region or disease specific efforts. In particular, the meeting served as a platform for assessing and discussing the recent progress made into the molecular elucidation of myotonic dystrophy.

  3. Chromosome numbers and meiotic analysis in the pre-breeding of Brachiaria decumbens (Poaceae)

    Indian Academy of Sciences (India)

    Gléia Cristina Laverde Ricci; Alice Maria De Souza-Kaneshima; Mariana Ferrari Felismino; Andrea Beatriz Mendes-Bonato; Maria Suely Pagliarini; Cacilda Borges Do Valle

    2011-08-01

    A total of 44 accessions of Brachiaria decumbens were analysed for chromosome count and meiotic behaviour in order to identify potential progenitors for crosses. Among them, 15 accessions presented $2n = 18$; 27 accessions, $2n = 36$; and 2 accessions, $2n = 45$ chromosomes. Among the diploid accessions, the rate of meiotic abnormalities was low, ranging from 0.82% to 7.93%. In the 27 tetraploid accessions, the rate of meiotic abnormalities ranged from 18.41% to 65.83%. The most common meiotic abnormalities were related to irregular chromosome segregation, but chromosome stickiness and abnormal cytokinesis were observed in low frequency. All abnormalities can compromise pollen viability by generating unbalanced gametes. Based on the chromosome number and meiotic stability, the present study indicates the apomictic tetraploid accessions that can act as male genitor to produce interspecific hybrids with B. ruziziensis or intraspecific hybrids with recently artificially tetraploidized accessions.

  4. Chromosome numbers and meiotic analysis in the pre-breeding of Brachiaria decumbens (Poaceae).

    Science.gov (United States)

    Ricci, Gléia Cristina Laverde; De Souza-Kaneshima, Alice Maria; Felismino, Mariana Ferrari; Mendes-Bonato, Andrea Beatriz; Pagliarini, Maria Suely; Do Valle, Cacilda Borges

    2011-08-01

    A total of 44 accessions of Brachiaria decumbens were analysed for chromosome count and meiotic behaviour in order to identify potential progenitors for crosses. Among them, 15 accessions presented 2n = 18; 27 accessions, 2n = 36; and 2 accessions, 2n = 45 chromosomes. Among the diploid accessions, the rate of meiotic abnormalities was low, ranging from 0.82% to 7.93%. In the 27 tetraploid accessions, the rate of meiotic abnormalities ranged from 18.41% to 65.83%. The most common meiotic abnormalities were related to irregular chromosome segregation, but chromosome stickiness and abnormal cytokinesis were observed in low frequency. All abnormalities can compromise pollen viability by generating unbalanced gametes. Based on the chromosome number and meiotic stability, the present study indicates the apomictic tetraploid accessions that can act as male genitor to produce interspecific hybrids with B. ruziziensis or intraspecific hybrids with recently artificially tetraploidized accessions.

  5. The HOX-5 and surfeit gene clusters are linked in the proximal portion of mouse chromosome 2.

    Science.gov (United States)

    Stubbs, L; Huxley, C; Hogan, B; Evans, T; Fried, M; Duboule, D; Lehrach, H

    1990-04-01

    Using an interspecies backcross, we have mapped the HOX-5 and surfeit (surf) gene clusters within the proximal portion of mouse chromosome 2. While the HOX-5 cluster of homeobox-containing genes has been localized to chromosome 2, bands C3-E1, by in situ hybridization, its more precise position relative to the genes and cloned markers of chromosome 2 was not known. Surfeit, a tight cluster of at least six highly conserved "housekeeping" genes, has not been previously mapped in mouse, but has been localized to human chromosome 9q, a region of the human genome with strong homology to proximal mouse chromosome 2. The data presented here place HOX-5 in the vicinity of the closely linked set of developmental mutations rachiterata, lethargic, and fidget and place surf close to the proto-oncogene Abl, near the centromere of chromosome 2.

  6. Assignment of Chinook salmon (Oncorhynchus tshawytscha) linkage groups to specific chromosomes reveals a karyotype with multiple rearrangements of the chromosome arms of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Phillips, Ruth B; Park, Linda K; Naish, Kerry A

    2013-12-09

    The Chinook salmon genetic linkage groups have been assigned to specific chromosomes using fluorescence in situ hybridization with bacterial artificial chromosome probes containing genetic markers mapped to each linkage group in Chinook salmon and rainbow trout. Comparison of the Chinook salmon chromosome map with that of rainbow trout provides strong evidence for conservation of large syntenic blocks in these species, corresponding to entire chromosome arms in the rainbow trout as expected. In almost every case, the markers were found at approximately the same location on the chromosome arm in each species, suggesting conservation of marker order on the chromosome arms of the two species in most cases. Although theoretically a few centric fissions could convert the karyotype of rainbow trout (2N = 58-64) into that of Chinook salmon (2N = 68) or vice versa, our data suggest that chromosome arms underwent multiple centric fissions and subsequent new centric fusions to form the current karyotypes. The morphology of only approximately one-third of the chromosome pairs have been conserved between the two species.

  7. Artificial intelligence in medicine.

    Science.gov (United States)

    Ramesh, A. N.; Kambhampati, C.; Monson, J. R. T.; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. RESULTS: The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. DISCUSSION: Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting. PMID:15333167

  8. Cloning and expression of transgenes using linear vectors in Trypanosoma cruzi.

    Science.gov (United States)

    Curto, María de Los Ángeles; Lorenzi, Hernán A; Moraes Barros, Roberto R; Souza, Renata T; Levin, Mariano J; Da Silveira, José Franco; Schijman, Alejandro G

    2014-06-01

    The identification of new targets for vaccine and drug development for the treatment of Chagas' disease is dependent on deepening our understanding of the parasite genome. Vectors for genetic manipulation in Trypanosoma cruzi basically include those that remain as circular episomes and those that integrate into the parasite's genome. Artificial chromosomes are alternative vectors to overcome problematic transgene expression often occurring with conventional vectors in this parasite. We have constructed a series of vectors named pTACs (Trypanosome Artificial Chromosomes), all of them carrying telomeric and subtelomeric sequences and genes conferring resistance to different selection drugs. In addition, one pTAC harbours a modified GFP gene (pTAC-gfp), and another one carries the ornithine decarboxilase gene from Crithidia fasciculata (pTAC-odc). We have encountered artificial chromosomes generated from pTACs in transformed T. cruzi epimastigotes for every version of the designed vectors. These extragenomic elements, in approximately 6-8 copies per cell, remained as linear episomes, contained telomeres and persisted after 150 and 60 generations with or without selection drugs, respectively. The linear molecules remained stable through the different T. cruzi developmental forms. Furthermore, derived artificial chromosomes from pTAC-odc could complement the auxotrophy of T. cruzi for polyamines. Our results show that pTACs constitute useful tools for reverse functional genetics in T. cruzi that will contribute to a better understanding of T. cruzi biology.

  9. Complementation of a defect in the asparagine-linked glycosylation of a mouse FM3A mutant G258 cell line by spheroplast fusion of a human mega YAC clone 923f5.

    Science.gov (United States)

    Masuda, Takahisa; Moriya, Masayuki; Kataoka, Kensuke; Nishikawa, Yoshihisa

    2012-01-01

    Mouse G258 mutant stopped both cell growth and the synthesis of lipid-linked oligosaccharide at the Man(3)GlcNAc(2)-P-P-Dolichol at a restricted temperature with a single gene mutation. To clarify the lesion in the G258 mutant, we isolated human genomic DNA transformants of the G258 mutant, which recovered from both defects by way of cell hybridization with X-ray irradiated HeLa cells. We detected a common 1.3-kb product by inter-human specific sequence in the L1 (L1Hs) PCR in the transformants (Kataoka et al., Somat. Cell Mol. Genet., 24, 235-243 (1998)). In the present study, we screened a human mega yeast artificial chromosome (YAC) library by PCR with primers designed according to the 1.3-kb DNA, and selected YAC clone 923f5. Moreover, we found by spheroplast fusion that YAC clone 923f5 complemented both defects of the G258 mutant. Since the human counterpart of the yeast ALG11 gene is localized in the region, the G258 mutant might have a defect in the mouse ALG11 gene.

  10. BURDEN OF ABNORMAL HEMATOPOIETIC CLONE IN PATIENTS WITH MYELODYSPLASTIC SYNDROMES

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To investigate the role of the burden of abnormal hematopoietic clone in the development of myelodys plastic syndromes (MDS).Methods The ratio of the bone marrow cells with abnormal chromosomes to the total counted bone marrow cells was regarded as the index of MDS clone burden. The disease severity related parameters including white blood cell count, hemoglobin, platelet count, lactate dehydrogenase level, bone marrow blast, myeloid differentiation index, micromegakaryocyte, transfusion, interleukin-2, tumor necrosis factor ( TNF), CD4 + and CD8 + T cells of MDS patients were assayed, and the correlations between those parameters and MDS clone burden were also analyzed.Results The clone burden of MDS patients was 67.4% ± 36. 2%. MDS clone burden positively correlated with bone marrow blasts (r=0.483, P<0.05), negatively with hemoglobin level (r=-0.445, P<0.05). The number of blasts, hemoglobin, and erythrocytes in high clone burden (>50%) and low clone burden (≤50%) groups were 7.78%±5.51% and 3.45%±3.34%, 56.06±14. 28 g/L and 76.40±24.44 g/L, (1.82±0.48)×1012/L and (2. 32±0.66)×1012/L, respectively (all P <0.05). CD4 + T lymphocytes of MDS patients and normal controls were (0. 274±0.719)×109/L and (0.455±0.206)×109/L, respectively (P<0.05). CD8 ± T lymphocytes of MDS patients and normal controls were (0.240±0.150)×109/L and (0.305 ±0.145)×109/L, respectively. The serum level of interleukin-2 of MDS patients (6.29±3.58 ng/mL) was significantly higher than normal control (3.11±1.40ng/mL, P<0.05). The serum level of TNF of MDS patients and normal control group were 2.42±1.79 ng/mL and 1.68 ±0.69 ng/mL, respectively. The ratio of CD4 to CD8 was higher in high clone burden MDS patients (1.90 ±0.52) than that in low clone burden patients (0.97±0.44, P<0.05).Conclusion The quantitive clonal karyotype abnormalities and deficient T cell immunity are important parameters for evaluating MDS severity and predicting its

  11. A sugar beet (Beta vulgaris L.) reference FISH karyotype for chromosome and chromosome-arm identification, integration of genetic linkage groups and analysis of major repeat family distribution.

    Science.gov (United States)

    Paesold, Susanne; Borchardt, Dietrich; Schmidt, Thomas; Dechyeva, Daryna

    2012-11-01

    We developed a reference karyotype for B. vulgaris which is applicable to all beet cultivars and provides a consistent numbering of chromosomes and genetic linkage groups. Linkage groups of sugar beet were assigned to physical chromosome arms by FISH (fluorescent in situ hybridization) using a set of 18 genetically anchored BAC (bacterial artificial chromosome) markers. Genetic maps of sugar beet were correlated to chromosome arms, and North-South orientation of linkage groups was established. The FISH karyotype provides a technical platform for genome studies and can be applied for numbering and identification of chromosomes in related wild beet species. The discrimination of all nine chromosomes by BAC probes enabled the study of chromosome-specific distribution of the major repetitive components of sugar beet genome comprising pericentromeric, intercalary and subtelomeric satellites and 18S-5.8S-25S and 5S rRNA gene arrays. We developed a multicolor FISH procedure allowing the identification of all nine sugar beet chromosome pairs in a single hybridization using a pool of satellite DNA probes. Fiber-FISH was applied to analyse five chromosome arms in which the furthermost genetic marker of the linkage group was mapped adjacently to terminal repetitive sequences on pachytene chromosomes. Only on two arms telomere arrays and the markers are physically linked, hence these linkage groups can be considered as terminally closed making the further identification of distal informative markers difficult. The results support genetic mapping by marker localization, the anchoring of contigs and scaffolds for the annotation of the sugar beet genome sequence and the analysis of the chromosomal distribution patterns of major families of repetitive DNA.

  12. CATO: The Clone Alignment Tool.

    Directory of Open Access Journals (Sweden)

    Peter V Henstock

    Full Text Available High-throughput cloning efforts produce large numbers of sequences that need to be aligned, edited, compared with reference sequences, and organized as files and selected clones. Different pieces of software are typically required to perform each of these tasks. We have designed a single piece of software, CATO, the Clone Alignment Tool, that allows a user to align, evaluate, edit, and select clone sequences based on comparisons to reference sequences. The input and output are designed to be compatible with standard data formats, and thus suitable for integration into a clone processing pipeline. CATO provides both sequence alignment and visualizations to facilitate the analysis of cloning experiments. The alignment algorithm matches each of the relevant candidate sequences against each reference sequence. The visualization portion displays three levels of matching: 1 a top-level summary of the top candidate sequences aligned to each reference sequence, 2 a focused alignment view with the nucleotides of matched sequences displayed against one reference sequence, and 3 a pair-wise alignment of a single reference and candidate sequence pair. Users can select the minimum matching criteria for valid clones, edit or swap reference sequences, and export the results to a summary file as part of the high-throughput cloning workflow.

  13. CATO: The Clone Alignment Tool.

    Science.gov (United States)

    Henstock, Peter V; LaPan, Peter

    2016-01-01

    High-throughput cloning efforts produce large numbers of sequences that need to be aligned, edited, compared with reference sequences, and organized as files and selected clones. Different pieces of software are typically required to perform each of these tasks. We have designed a single piece of software, CATO, the Clone Alignment Tool, that allows a user to align, evaluate, edit, and select clone sequences based on comparisons to reference sequences. The input and output are designed to be compatible with standard data formats, and thus suitable for integration into a clone processing pipeline. CATO provides both sequence alignment and visualizations to facilitate the analysis of cloning experiments. The alignment algorithm matches each of the relevant candidate sequences against each reference sequence. The visualization portion displays three levels of matching: 1) a top-level summary of the top candidate sequences aligned to each reference sequence, 2) a focused alignment view with the nucleotides of matched sequences displayed against one reference sequence, and 3) a pair-wise alignment of a single reference and candidate sequence pair. Users can select the minimum matching criteria for valid clones, edit or swap reference sequences, and export the results to a summary file as part of the high-throughput cloning workflow.

  14. [The discrete horror of cloning].

    Science.gov (United States)

    Guibourg, Ricardo A

    2009-01-01

    The author raises the topic of cloning after the decision of the Argentine government, which concerned for the "dignity of the human person", passed a decree of need and urgency, No. 200/97 (Annex), prohibiting cloning experiments with human beings. Therefore, considering that the topic is so terribly urgent and necessary, the author feels it is timely to consider it.

  15. Chromosomal Organization and Sequence Diversity of Genes Encoding Lachrymatory Factor Synthase in Allium cepa L.

    Science.gov (United States)

    Masamura, Noriya; McCallum, John; Khrustaleva, Ludmila; Kenel, Fernand; Pither-Joyce, Meegham; Shono, Jinji; Suzuki, Go; Mukai, Yasuhiko; Yamauchi, Naoki; Shigyo, Masayoshi

    2012-06-01

    Lachrymatory factor synthase (LFS) catalyzes the formation of lachrymatory factor, one of the most distinctive traits of bulb onion (Allium cepa L.). Therefore, we used LFS as a model for a functional gene in a huge genome, and we examined the chromosomal organization of LFS in A. cepa by multiple approaches. The first-level analysis completed the chromosomal assignment of LFS gene to chromosome 5 of A. cepa via the use of a complete set of A. fistulosum-shallot (A. cepa L. Aggregatum group) monosomic addition lines. Subsequent use of an F(2) mapping population from the interspecific cross A. cepa × A. roylei confirmed the assignment of an LFS locus to this chromosome. Sequence comparison of two BAC clones bearing LFS genes, LFS amplicons from diverse germplasm, and expressed sequences from a doubled haploid line revealed variation consistent with duplicated LFS genes. Furthermore, the BAC-FISH study using the two BAC clones as a probe showed that LFS genes are localized in the proximal region of the long arm of the chromosome. These results suggested that LFS in A. cepa is transcribed from at least two loci and that they are localized on chromosome 5.

  16. A molecularly defined duplication set for the X chromosome of Drosophila melanogaster

    Energy Technology Data Exchange (ETDEWEB)

    Venken, Koen J. T.; Popodi, Ellen; Holtzman, Stacy L.; Schulze, Karen L.; Park, Soo; Carlson, Joseph W.; Hoskins, Roger A.; Bellen, Hugo J.; Kaufman, Thomas C.

    2010-07-22

    We describe a molecularly defined duplication kit for the X chromosome of Drosophila melanogaster. A set of 408 overlapping P[acman] BAC clones was used to create small duplications (average length 88 kb) covering the 22-Mb sequenced portion of the chromosome. The BAC clones were inserted into an attP docking site on chromosome 3L using C31 integrase, allowing direct comparison of different transgenes. The insertions complement 92% of the essential and viable mutations and deletions tested, demonstrating that almost all Drosophila genes are compact and that the current annotations of the genome are reasonably accurate. Moreover, almost all genes are tolerated at twice the normal dosage. Finally, we more precisely mapped two regions at which duplications cause diplo-lethality in males. This collection comprises the first molecularly defined duplication set to cover a whole chromosome in a multicellular organism. The work presented removes a long-standing barrier to genetic analysis of the Drosophila X chromosome, will greatly facilitate functional assays of X-linked genes in vivo, and provides a model for functional analyses of entire chromosomes in other species.

  17. Quantum probabilistically cloning and computation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this article we make a review on the usefulness of probabilistically cloning and present examples of quantum computation tasks for which quantum cloning offers an advantage which cannot be matched by any approach that does not resort to it.In these quantum computations,one needs to distribute quantum information contained in states about which we have some partial information.To perform quantum computations,one uses state-dependent probabilistic quantum cloning procedure to distribute quantum information in the middle of a quantum computation.And we discuss the achievable efficiencies and the efficient quantum logic network for probabilistic cloning the quantum states used in implementing quantum computation tasks for which cloning provides enhancement in performance.

  18. Artificial Neural Networks

    OpenAIRE

    Chung-Ming Kuan

    2006-01-01

    Artificial neural networks (ANNs) constitute a class of flexible nonlinear models designed to mimic biological neural systems. In this entry, we introduce ANN using familiar econometric terminology and provide an overview of ANN modeling approach and its implementation methods.

  19. Introduction to artificial intelligence

    Science.gov (United States)

    Cheeseman, P.; Gevarter, W.

    1986-01-01

    This paper presents an introductory view of Artificial Intelligence (AI). In addition to defining AI, it discusses the foundations on which it rests, research in the field, and current and potential applications.

  20. A 2-megabase physical contig incorporating 43 DNA markers on the human X chromosome at p11.23-p11.22 from ZNF21 to DXS255

    Energy Technology Data Exchange (ETDEWEB)

    Boycott, K.M.; Bech-Hansen, N.T. [Univ. of Calgary, Alberta (Canada); Halley, G.R.; Schlessinger, D. [Washington Univ. School of Medicine, St. Louis, MO (United States)

    1996-05-01

    A comprehensive physical contig of yeast artificial chromosomes (YACs) and cosmid clones between ZNF21 and DXS255 has been constructed, spanning 2 Mb within the region Xp11.23-p11.22. As a portion of the region was found to be particularly unstable in yeast, the integrity of the contig is dependent on additional information provided by the sequence-tagged site (STS) content of cosmid clones and DNA marker retention in conventional and radiation hybrids. The contig was formatted with 43 DNA markers, including 19 new STSs from YAC insert ends and an internal Alu-PCR product. The density of STSs across the contig ranges from one marker every 20 kb to one every 60 kb, with an average density of one marker every 50 kb. The relative order of previously known gene and expressed sequence tags in this region is predicted to be Xpter-ZNF21-DXS7465E (MG66)-DXS7927E (MG81)-WASP, DXS1011E, DXS7467E (MG21)-DXS-7466E (MG44)-GATA1-DXS7469E (Xp664)-TFE3-SYP (DXS1007E)-Xcen. This contig extends the coverage in Xp11 and provides a framework for the future identification and mapping of new genes, as well as the resources for developing DNA sequencing templates. 47 refs., 1 fig., 4 tabs.