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91.
Sara Montanari Munazza Saeed Mareike Kn?bel YoonKyeong Kim Michela Troggio Mickael Malnoy Riccardo Velasco Paolo Fontana KyungHo Won Charles-Eric Durel Laure Perchepied Robert Schaffer Claudia Wiedow Vincent Bus Lester Brewer Susan E. Gardiner Ross N. Crowhurst David Chagné 《PloS one》2013,8(10)
We have used new generation sequencing (NGS) technologies to identify single nucleotide polymorphism (SNP) markers from three European pear (Pyrus communis L.) cultivars and subsequently developed a subset of 1096 pear SNPs into high throughput markers by combining them with the set of 7692 apple SNPs on the IRSC apple Infinium® II 8K array. We then evaluated this apple and pear Infinium® II 9K SNP array for large-scale genotyping in pear across several species, using both pear and apple SNPs. The segregating populations employed for array validation included a segregating population of European pear (‘Old Home’בLouise Bon Jersey’) and four interspecific breeding families derived from Asian (P. pyrifolia Nakai and P. bretschneideri Rehd.) and European pear pedigrees. In total, we mapped 857 polymorphic pear markers to construct the first SNP-based genetic maps for pear, comprising 78% of the total pear SNPs included in the array. In addition, 1031 SNP markers derived from apple (13% of the total apple SNPs included in the array) were polymorphic and were mapped in one or more of the pear populations. These results are the first to demonstrate SNP transferability across the genera Malus and Pyrus. Our construction of high density SNP-based and gene-based genetic maps in pear represents an important step towards the identification of chromosomal regions associated with a range of horticultural characters, such as pest and disease resistance, orchard yield and fruit quality. 相似文献
92.
Quantitative electroelution of oligonucleotides and large DNA fragments from gels and purification by electrodialysis 总被引:5,自引:0,他引:5
We have designed a new device [Biotrap (Elutrap in the U.S.A. and Canada), available from Schleicher & Schuell] for electroelution, -concentration , and -dialysis of DNA and other charged macromolecules above 5 kDa. In an electric field, the DNA migrates in an open channel out of the gel slice through a microporous membrane, BT2, into the trap section, where it is retained by a very dense, non-adsorbant, and inert membrane BT1. Specifically designed for use in an electric field, the matrix of this new membrane is much denser than that of dialysis membranes. In contrast to dialysis membranes, BT1 will not adsorb large DNA fragments nor allow passage of small DNA fragments when subjected to an electric field. In the absence of an electric field, BT1 and BT2 effectively seal the trap, maintaining the final elution volume of the purified sample. The trap can contain from 200-600 microliter and is collected from above with a pipet. In the experiments described here, 85-95% of oligonucleotides (14-mer) and large (150 kb) DNA fragments were recovered, independent of fragment length. The purity of the eluted DNA was demonstrated by restriction enzyme digestion, nick-translation, primer extension, end-labeling with polynucleotide kinase, and ligation. Electrodialysis was successfully used for the complete removal of common contaminants inhibiting the polynucleotide kinase reaction and for the removal of CsCl from DNA samples. 相似文献
93.
Recently, we described the distribution of testosterone-metabolizing enzymes (i.e., aromatase, 5 alpha- and 5 beta-reductases) in the zebra finch (Taeniopygia guttata) brain using a sensitive radioenzyme assay combined to the Palkovits punch method. A number of sex-differences in the activity of these enzymes were observed especially in nuclei of the song-control system. The hormonal controls of these differences have now been analyzed by gonadectomizing birds of both sexes and by giving them a replacement therapy with silastic implants of testosterone (T). Five nuclei of the song system (Area X [X], nucleus magnocellularis of the anterior neostriatum [MAN], nucleus robustus archistriatalis [RA], nucleus intercollicularis [ICo], hyperstriatum ventrale, pars caudalis [HVc]) and three preoptic-hypothalamic areas (preoptic anterior [POA], periventricular magnocellular nucleus [PVM], and posterior medial hypothalamic nucleus [PMH]) were studied as well as other limbic and control non-steroid-sensitive areas. The activity of the 5 alpha-reductase was higher in males than in females for the five song-control nuclei and was not affected by the hormonal treatments. The overall activity of this enzyme was not sexually dimorphic in POA and PVM. It was higher in males than in females in intact birds only, and was reduced by gonadectomy and enhanced by T. The activity of the 5 beta-reductase was higher in females than in males in all nuclei of the song system and in POA, but was not influenced by the changes in T level. Both sex and treatment effects were observed in the control of aromatase. The production of estrogens was dimorphic (females greater than males) in RA and PMH. It was increased by T in POA, PVM, and PMH, and also in RA. These data show that some of the sex differences in T-metabolizing enzymes result from the exposure to different levels of T in adulthood (e.g., 5 alpha-reductase in POA and PVM or aromatase in PVM), whereas others persist even if birds are exposed to the same hormonal conditions. These are presumably the result of organizational effects of steroids. The steroid modulation of the aromatase might be related directly to the activation of sexual, aggressive, and nest-building behaviors, whereas the stable dimorphism in 5 alpha- and 5 beta-reductase observed in the nuclei of the song system might be one of the neurochemical bases of the sex differences in the vocal behavior of the zebra finch. 相似文献
94.
Liang Ru Shi Dirk Eichelbauer Franz Borchard Herbert Jürgens Ulrich Göbel E. Marion Schneider 《Cancer immunology, immunotherapy : CII》1994,38(3):208-213
A selection of 16 monoclonal antibodies has been produced against a fresh Ewing's sarcoma (ES) tumor mixed with a permanent ES cell line. The majority of antibodies identify an 80-kDa molecule, which is not detected on healthy tissues except on certain cultured monocytes. One antibody recognize the CD2 ligand MIC2 and 2 antibodies (numbers 13 and 16) define a higher-molecular-mass antigen. Antibody 16 is also expressed on mesenchymal fibroblasts of bone marrow or fetal origin. Tumorspecific antigen expression is potentially linked to the chromosome 22 abnormality decribed in Ewing's sarcoma. 相似文献
95.
Johannes Pr?ll Martin Danzer Stephanie Stabentheiner Norbert Niklas Christa Hackl Katja Hofer Sabine Atzmüller Peter Hufnagl Christian Gülly Hanns Hauser Otto Krieger Christian Gabriel 《DNA research》2011,18(4):201-210
How cells coordinate the immune system activities is important for potentially life-saving organ or stem cell transplantations. Polymorphic immunoregulatory genes, many of them located in the human major histocompatibility complex, impact the process and assure the proper execution of tolerance-versus-activity mechanisms. In haematopoietic stem cell transplantation, on the basis of fully human leukocyte antigen (HLA)-matched donor–recipient pairs, adverse effects like graft versus leukaemia and graft versus host are observed and difficult to handle. So far, high-resolution HLA typing was performed with Sanger sequencing, but for methodological reasons information on additional immunocompetent major histocompatibility complex loci has not been revealed. Now, we have used microarray sequence capture and targeted enrichment combined with next generation pyrosequencing for 3.5 million base pair human major histocompatibility complex resequencing in a clinical transplant setting and describe 3025 variant single nucleotide polymorphisms, insertions and deletions among recipient and donor in a single sequencing experiment. Taken together, the presented data show that sequence capture and massively parallel pyrosequencing can be used as a new tool for risk assessment in the setting of allogeneic stem cell transplantation. 相似文献
96.
The non-cytotoxic concentration (20 microM) of menadione (2-methyl-1,4-naphthoquinone), after 1 h of incubation, leads to loss of the activity of rhodanese by 33%, 3-mercaptopyruvate sulfurtransferase by 20%, as well as the level of sulfane sulfur by about 23% and glutathione by 12%, in the culture of U373 cells, in comparison with the control culture. Reactive oxygen species generated by menadione oxidize sulfhydryl groups in active centers of the investigated enzymes, inhibiting them and saving cysteine for glutathione synthesis. A decreased sulfane sulfur level can be correlated with an oxidative stress. 相似文献
97.
P. Schmitt C. Couvreur J. F. Cavin H. Prévost Ch. Diviès 《Applied microbiology and biotechnology》1988,29(5):430-436
Summary The effects of pH, temperature and concentration of citrate were investigated to achieve an optimal production of diacetyl, acetoin and C2 compounds such as acetaldehyde, acetate and ethanol for free and immobilized cells. The critical conditions of culture, 22°C, pH 4.8, increased the production of C4 compounds (diacetyl, acetoin, 2, 3 butylene glycol), C2 compounds (acetaldehyde, ethanol, acetate) and formate. A higher yield of C2 and C4 compounds was observed for the immobilized cells than for the free cells in continuous culture. At 75 mMol/l of citrate, the citrate bioconversion yield was 42.8% and 80% for free and immobilized cells, respectively. This paper discusses citrate and lactose utilization and NADH2 part on diacetyl reduction. 相似文献
98.
99.
Alvarez F Castro M Príncipe A Borioli G Fischer S Mori G Jofré E 《Journal of applied microbiology》2012,112(1):159-174
Aims: This work was conducted to identify the antifungal compounds produced by two previously isolated Bacillus sp. strains: ARP23 and MEP218. Both strains were subjected to further analysis to determine their taxonomic position and to identify the compounds responsible for their antifungal activity as well as to evaluate the efficiency of these strains to control sclerotinia stem rot in soybean. Methods and Results: The antifungal compounds were isolated by acid precipitation of cell‐free supernatants, purified by RP‐HPLC and then tested for antagonistic activity against Sclerotinia sclerotiorum. Mass spectra from RP‐HPLC eluted fractions showed the presence of surfactin C15, fengycins A (C16–C17) and B (C16) isoforms in supernatants from strain ARP23 cultures, whereas the major lipopeptide produced by strain MEP218 was iturin A C15. Alterations in mycelial morphology and sclerotial germination were observed in the presence of lipopeptides‐containing supernatants from Bacillus strains cultures. Foliar application of Bacillus amyloliquefaciens strains on soybean plants prior to S. sclerotiorum infection resulted in significant protection against sclerotinia stem rot compared with noninoculated plants or plants inoculated with a nonlipopeptide‐producing B. subtilis strain. Conclusions: Both strains, renamed as B. amyloliquefaciens ARP23 and MEP218, were able to produce antifungal compounds belonging to the cyclic lipopeptide family. Our data suggest that the foliar application of lipopeptide‐producing B. amyloliquefaciens strains could be a promising strategy for the management of sclerotinia stem rot in soybean. Significance and Impact of the Study: Sclerotinia stem rot was ranked as one of the most severe soybean disease in Argentina and worldwide. The results of this study showed the potential of B. amyloliquefaciens strains ARP23 and MEP218 to control plant diseases caused by S. sclerotiorum. 相似文献
100.
Gunnhild Jakobsen Morten Engstrøm Ørnulf Paulsen Karin Sjue Sunil X. Raj Morten Thronæs Marianne Jensen Hjermstad Stein Kaasa Peter Fayers Pål Klepstad 《Trials》2018,19(1):707