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991.
992.
993.
Jason Witherington Lee Abberley Benjamin R. Bellenie Rio Boatman Katharine Collis David K. Dean Alessandra Gaiba N. Paul King Nicola Shuker Jon G.A. Steadman Andrew K. Takle Gareth Sanger Sharon Butler Fiona McKay Alison Muir Kim Winborn Robert W. Ward Tom D. Heightman 《Bioorganic & medicinal chemistry letters》2009,19(3):684-687
As part of an on-going lead optimisation effort, a cross screening exercise identified an aryl sulphonyl amide hit that was optimised to afford a highly potent series of ghrelin receptor agonists. 相似文献
994.
Centromeric Regions Control Autonomous Segregation Tendencies in Single-Division Meiosis of Saccharomyces Cerevisiae 总被引:2,自引:1,他引:1 下载免费PDF全文
We have previously shown that yeast cdc5 or cdc14 homozygotes can be led through a single-division meiosis in which some of the chromosomes segregate reductionally whereas others, within the same cell, segregate equationally. Chromosomes XI tend to segregate reductionally, whereas chromosomes IV tend to segregate equationally. In this report we present experiments with cdc5 homozygous strains, in which the centromeres of one or both chromosomes XI was replaced by the centromeric region from chromosome IV. Analysis of the products of single-division meioses in these strains demonstrates that the choice between reductional or equational segregation is directed by sequences in the vicinity of the centromeres. Although the choice is made separately for each individual chromosome, the analysis also reveals the existence of a system responsible for coordinated segregation of the two chromosomes of a given pair. 相似文献
995.
Sharon Y. Strauss 《Oecologia》1990,84(1):111-116
Summary Patchiness in herbivore attack is a well-documented phenomenon. When neighboring plants suffer vastly different levels of
attack, then one suspects genotypic differences among plants to be the underlying mechanism. In this study, I use common garden
experiments in two natural, but divergent, habitats at the Cedar Creek Natural History Area in central Minnesota to determine
the role of plant genotype, environment and gender in plant resistance to a specialist herbivore. Resistance was measured
by larval survivorship and weight. Eight clones ofRhus glabra were selected and 12 equal-aged ramets were dug up and planted in two gardens (each garden received 6 ramets per clone).
First instarBlepharida rhois (Coleoptera: Chrysomelidae) larvae of known parentage were transferred to ramets and censused every other day. At the end
of the experiment, larvae were collected and weighed. Analysis of variance was used to determine the importance of plant genotype,
environment and gender on larval mortality and weight. The experiment was repeated in its entirety one month later. Both plant
genotype and environment significantly affected larval survivorship in the first run of the experiment. No interactions were
significant. Results from the second run indicated marginally significant genotype and environment main effects, and a genotype
by environment interaction in larval survivorship. There was a significant genotype by environment interaction in larval weight
on the same run. In neither run did clone gender have significant affects on resistance. 相似文献
996.
Class II genes of miniature swine 总被引:2,自引:0,他引:2
Frances Hirsch David H. Sachs Kenth Gustafson Karen Pratt Sharon Germana Christian LeGuern 《Immunogenetics》1990,31(1):52-56
Genomic clones corresponding to class II genes of theSLA
c haplotype of miniature swine have been isolated and characterized. These genes have been grouped into seven non-overlapping clusters on the basis of restriction mapping. Ordering of exons within each cluster was accomplished by hybridization of Southern blots of restriction fragments with exon-specific probes. The two clusters (clusters 2 and 3) encoding theDRB andDQB genes were identified on the basis of hybridization with locus-specific 3 untranslated cDNA probes. Cluster 4 contained exons of bothDOB andDQB genes, the basis for which remains to be determined. The remaining four clusters (1, 5, 6, 7) were identified as containingDP, DR, andDO coding sequences, respectively, on the basis of sequence analysis. The porcine class II region appears very similar to that of man in number and nature of the class II genes identified and in the intron/exon organization of corresponding genes.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the association number M29944.
Address correspondence and offprint requests to: C. LeGuern. 相似文献
997.
Siu-Leung Lee Minocher Reporter Sharon N. Hsu James L. Corbin Gregory Luli Paul L. Burkhouse John H. Litchfield 《Journal of industrial microbiology & biotechnology》1988,3(5):293-297
Summary A cell line, NA13-2, was selected as a rapidly growing colony of protoplasts from a UV(254 nm)-fluorescent cell line, NA13-1, which originated from a tryptamine-resistant strain ofCatharanthus roseus NA13. Cell line NA13-2 lost the capability to produce indole alkaloids. Tryptophan fed to these cells was converted toN
b-acetyltryptamine as the major product. The free acetyl coenzyme A content of NA13-2 cells was 50% higher than in the mother cells. The total lipid content of the NA13-2 cells was 2.5-fold that in the NA13 cells. In spite of the similarity in the fatty acid content to that of the mother cell line NA13, the total lipid extract of NA13-2 cells appeared as a wax instead of an oil, resulting from the presence of sterol esters.This paper was presented in part at the Annual Meeting of the Society for Industrial Microbiology, Boston, MA, 1985, and the International Congress of the Plant Tissue Culture Association, Minneapolis, MN, 1986. 相似文献
998.
M Sharon J R Gnarra M Baniyash W J Leonard 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(10):3512-3515
In the process of evaluating murine hybridomas for an antibody to the beta-subunit of the IL-2R (p70) we identified an antibody that immunoprecipitated a 55- to 57-kDa complex from cross-linked lysates. We demonstrate that this complex is composed of IL-2 (15.5 kDa) cross-linked to the H chain of HLA class I (40 to 42 kDa), suggesting a molecular interaction between HLA class I molecules and IL-2R. Although the exact role of this association remains to be determined, the specific cross-linking of IL-2 to HLA class I Ag is intriguing in view of published claims for a role of HLA class I in OKT3-induced lymphocyte proliferation and in NK cell lytic activity. 相似文献
999.
The invariant tryptophan in an H chain V region is not essential to antibody binding 总被引:3,自引:0,他引:3
J Sharon 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(8):2666-2669
The first amino acid residue of the second framework region in all antibody H and L chain V regions sequenced to date is invariably tryptophan. To test whether this invariance is essential to proper domain folding and generation of a functional antibody, the tryptophan residue in the heavy chain V region of a mouse anti-p-azophenylarsonate antibody was converted to an alanine residue by oligonucleotide-directed mutagenesis of the H chain gene. The mutant gene was transfected into mouse hybridoma cells that produce the homologous L chain, and the resulting mutant antibody was purified from the cell supernatant. It was shown to have essentially the same reactivity as wild type toward a series of anti-idiotypic antibodies and to bind Ag with a Ka similar to that of wild type. 相似文献
1000.
Sharon L. Campbell-Burka Peter J. Domaillea Melissa A. Starovasnik Wayne Boucher Ernest D. Laue 《Journal of biomolecular NMR》1992,2(6):639-646
Summary The c-H-ras p21 protein is the product of the humanras proto-oncogene, a member of a ubiquitous eukaryotic gene family which is highly conserved in evolution. These proteins play an important role in the control of cellular growth. We report here the sequential assignment of the backbone nuclei in a truncated form of the 21-kD gene product, using our recently proposed 4D NMR strategy (Boucher et al., 1992). These assignments are the first step towards a full investigation of the structure, dynamics and interactions of wild-type and oncogenicrasp21 using NMR spectroscopy. Some of the data were presented at the 33rd ENC held at Asilomar, California, U.S.A., in April 1992.Supplementary material is available from the corresponding authors: One table containing the complete resonance assignment of c-H-ras p21 (1–166).GDP. 相似文献