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51.
Tom Drader Kara Johnson Robert Brueggeman Dave Kudrna Andris Kleinhofs 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):811-820
Approaches utilizing microlinearity between related species allow for the identification of syntenous regions and orthologous
genes. Within the barley Chromosome 7H(1) is a region of high recombination flanked by molecular markers cMWG703 and MWG836.
We present the constructed physical contigs linked to molecular markers across this region using bacterial artificial chromosomes
(BAC) from the cultivar Morex. Barley expressed sequence tags (EST), identified by homology to rice chromosome 6 between the
rice molecular markers C425A and S1434, corresponded to the barley syntenous region of Chromosome 7H(1) Bins 2–5 between molecular
markers cMWG703-MWG836. Two hundred and thirteen ESTs were genetically mapped yielding 267 loci of which 101 were within the
target high recombination region while 166 loci mapped elsewhere. The 101 loci were joined by 43 other genetic markers resulting
in a highly saturated genetic map. In order to develop a physical map of the region, ESTs and all other molecular markers
were used to identify Morex BAC clones. Seventy-four BAC contigs were formed containing 2–102 clones each with an average
of 19 and a median of 13 BAC clones per contig. Comparison of the BAC contigs, generated here, with the Barley Physical Mapping
Database contigs, resulted in additional overlaps and a reduction of the contig number to 56. Within cMWG703-MWG836 are 24
agriculturally important traits including the seedling spot blotch resistance locus, Rcs5. Genetic and physical analysis of this region and comparison to rice indicated an inversion distal of the Rcs5 locus. Three BAC clone contigs spanning the Rcs5 locus were identified.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
52.
John Ambler Emma Baker Lyndon Brown Paul Butler Dave Farr Karen Dunnet Darren Le Grand Diana Janus Darryl Jones Keith Menear Mark Mercer Garrick Smith Mark Talbot Morris Tweed 《Bioorganic & medicinal chemistry letters》1998,8(24):189-3588
The chemical optimisation of CGH1668 1 is described employing an in vivo model of absorption to determine the influence on bioavailability of single point modifications to five key molecular templates. The discovery of an orally bioavailable and selective thrombin inhibitor, 24, highlights the utility of this approach. 相似文献
53.
Proteome analysis of early somatic embryogenesis in Picea glauca 总被引:3,自引:0,他引:3
Lippert D Zhuang J Ralph S Ellis DE Gilbert M Olafson R Ritland K Ellis B Douglas CJ Bohlmann J 《Proteomics》2005,5(2):461-473
Forestry is a valuable natural resource for many countries. Rapid production of large quantities of genetically improved and uniform seedlings for restocking harvested lands is a key component of sustainable forest management programs. Clonal propagation through somatic embryogenesis has the potential to meet this need in conifers and can offer the added benefit of ensuring consistent seedling quality. Although in commercial use, mass production of conifers through somatic embryogenesis is relatively new and there are numerous biological unknowns regarding this complex developmental pathway. To aid in unravelling the embryo developmental process, two-dimensional electrophoresis was employed to quantitatively assess the expression levels of proteins across four stages of somatic embryo maturation in white spruce (0, 7, 21 and 35 days post abscisic acid treatment). Forty-eight differentially expressed proteins have been identified, which display a significant change in abundance as early as day 7 of embryo development. These proteins are involved in a variety of cellular processes, many of which have not previously been associated with embryo development. The identification of these proteins was greatly assisted by the availability of a substantial expressed sequence tag (EST) resource developed for white, sitka and interior spruce. The combined use of these spruce ESTs in conjunction with GenBank accessions for other plants improved the rate of protein identification from 38% to 62% when compared with GenBank alone using automated, high-throughput techniques. This underscores the utility of EST resources in a proteomic study of any species for which a genome sequence is unavailable. 相似文献
54.
Dave C. Christophel 《American journal of botany》1973,60(1):61-66
A new Sciadopitys-like conifer is described on the basis of compression fossils of shoots and leaves found at the Smokey Tower locality in western Alberta. The specimens consist of long, strap-like leaves attached in apparent whorls and subtended by groups of scale leaves. Other scale leaves are borne in loose spirals on the shoots between whorls. These specimens represent the first record of Sciadopitys-like foliage from western North America. Comparisons are made with extant and extinct species of the genus Sciadopitys (Siebold and Zuccarini, 1841) and with the widely distributed fossil genus Sciadopitytes (Goeppert and Menge, 1883). 相似文献
55.
56.
Luke Tornabene Gabby N. Ahmadia Michael L. Berumen Dave J. Smith Jamaluddin Jompa Frank Pezold 《Molecular phylogenetics and evolution》2013,66(1):391-400
Gobies (Teleostei: Gobiidae) are an extremely diverse and widely distributed group and are the second most species rich family of vertebrates. Ecological drivers are key to the evolutionary success of the Gobiidae. However, ecological and phylogenetic data are lacking for many diverse genera of gobies. Our study investigated the evolution of microhabitat association across the phylogeny of 18 species of dwarfgobies (genus Eviota), an abundant and diverse group of coral reef fishes. In addition, we also explore the evolution of pectoral fin-ray branching and sensory head pores to determine the relationship between morphological evolution and microhabitat shifts. Our results demonstrate that Eviota species switched multiple times from a facultative hard-coral association to inhabiting rubble or mixed sand/rubble habitat. We found no obvious relationship between microhabitat shifts and changes in pectoral fin-ray branching or reduction in sensory pores, with the latter character being highly homoplasious throughout the genus. The relative flexibility in coral-association in Eviota combined with the ability to move into non-coral habitats suggests a genetic capacity for ecological release in contrast to the strict obligate coral-dwelling relationship commonly observed in closely related coral gobies, thus promoting co-existence through fine scale niche partitioning. The variation in microhabitat association may facilitate opportunistic ecological speciation, and species persistence in the face of environmental change. This increased speciation opportunity, in concert with a high resilience to extinction, may explain the exceptionally high diversity seen in Eviota compared to related genera in the family. 相似文献
57.
Background
Fine tuning expression of genes is a prerequisite for the strictly human pathogen Neisseria meningitidis to survive hostile growth conditions and establish disease. Many bacterial species respond to stress by using alternative σ factors which, in complex with RNA polymerase holoenzyme, recognize specific promoter determinants. σE, encoded by rpoE (NMB2144) in meningococci, is known to be essential in mounting responses to environmental challenges in many pathogens. Here we identified genes belonging to the σE regulon of meningococci. 相似文献58.
First detection of Nosema ceranae, a microsporidian parasite of European honey bees (Apis mellifera), in Canada and central USA 总被引:1,自引:0,他引:1
Williams GR Shafer AB Rogers RE Shutler D Stewart DT 《Journal of invertebrate pathology》2008,97(2):189-192
Nosema ceranae is an emerging microsporidian parasite of European honey bees, Apis mellifera, but its distribution is not well known. Six Nosema-positive samples (determined from light microscopy of spores) of adult worker bees from Canada (two each from Nova Scotia, New Brunswick, and Prince Edward Island) and two from USA (Minnesota) were tested to determine Nosema species using previously-developed PCR primers of the 16S rRNA gene. We detected for the first time N. ceranae in Canada and central USA. One haplotype of N. ceranae was identified; its virulence may differ from that of other haplotypes. 相似文献
59.
Methylation of p16 and Ras association domain family protein 1a during colorectal malignant transformation 总被引:2,自引:0,他引:2
Umetani N de Maat MF Sunami E Hiramatsu S Martinez S Hoon DS 《Molecular cancer research : MCR》2006,4(5):303-309
Accurate assessment of gene methylation in formalin-fixed, paraffin-embedded archived tissue (FF-PEAT) by microdissection remains challenging because the tissue volume is small and DNA is damaged. In addition, methods for methylation assessment, such as methylation-specific PCR (MSP), require sodium bisulfite modification (SBM) on purified DNA, which causes major loss of DNA. On-slide SBM, in which DNA is modified in situ before isolation of tumor cells, eliminates DNA purification steps and allows histology-oriented assessment of gene methylation. This study describes a protocol and use of on-slide SBM using 20 FF-PEAT of colorectal cancers with intratumoral adenoma components to detect accumulation of gene methylation during colorectal malignant transformation. Deparaffinized tissue sections were incubated in sodium bisulfite solution for 8 hours at 60 degrees C, stained with hematoxylin, and then microdissected. Proteinase K lysate was directly used as a template in subsequent PCR. Using on-slide SBM, 282-bp-long bisulfite direct sequencing was possible. Yield of modified DNA was 2.6-fold greater than standard SBM on average. The mean conversion rate was 97%, and false-positive or false-negative results were not observed in subsequent MSP. Intratumoral heterogeneity by accumulation of p16 and Ras association domain family protein 1a methylation during malignant transformation were shown by MSP comparing cancer with adenoma parts within a single section. On-slide SBM is applicable in most methylation studies using FF-PEAT. It allows detailed, intratumoral analysis of methylation heterogeneity within solid tumors. On-slide SBM will significantly improve our approach and understanding of epigenetic events in minimal disease and the carcinogenic process. 相似文献
60.