334 research outputs found

    Lack of an Interchromosomal Effect Associated with Spontaneous Recombination in Males of Drosophila Melanogaster

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    Author Institution: Department of Biological Sciences, Bowling Green State UniversityIt is shown that the frequency of spontaneous male recombination in two different lines of Drosophila melanogaster (OKI and T-007) are not subject to an interchromosomal effect. Second-chromosome male recombination in these lines was not affected by heterozygosity for the multiple third-chromosome inversions In(3LR)TM3 or In(3LR)Ubxm, which do affect recombination in females. It seems, therefore, that a large fraction of spontaneous recombination in males of D. melanogaster occurs by some mechanism other than that in females. We discuss the possibility that the mechanism is chromosome breakage and reunion, and that these breakage events may be caused by a microorganism

    Pendokumentasian Aplikasi Ragam Hias Budaya Bali, sebagai Upaya Konservasi Budaya Bangsa Khususnya pada Perancangan Interior

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    Various ornament of Indonesian people comes from the ethnic groups from all over the archipelago. As a tangible cultural ornament has a specific purpose and it does not change throughout the ages. Bali is one of the ethnic group in archipelago that has beautiful decorative art and one of the most popular tourism destination in Indonesia. Bali\u27s ornament generally seen as decorative carving on the column, window or even in door. The beauty of Bali is not only as an inspiration for their colors and sculpture but also the variety of forms that have been simplified in the ornament. Moreover, floral & fauna forms are easy to apply as an interior element in modern buildings. Generally the value of these ornament has a specific purpose related to the cultural and social custom in Bali people. So that the application need to consider more about the purpose of the symbol of the ornament

    Nematode-Bacterium Symbioses—Cooperation and Conflict Revealed in the “Omics” Age

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    Nematodes are ubiquitous organisms that have a significant global impact on ecosystems, economies, agriculture, and human health. The applied importance of nematodes and the experimental tractability of many species have promoted their use as models in various research areas, including developmental biology, evolutionary biology, ecology, and animal-bacterium interactions. Nematodes are particularly well suited for the investigation of host associations with bacteria because all nematodes have interacted with bacteria during their evolutionary history and engage in a variety of association types. Interactions between nematodes and bacteria can be positive (mutualistic) or negative (pathogenic/parasitic) and may be transient or stably maintained (symbiotic). Furthermore, since many mechanistic aspects of nematode-bacterium interactions are conserved, their study can provide broader insights into other types of associations, including those relevant to human diseases. Recently, genome-scale studies have been applied to diverse nematode-bacterial interactions and have helped reveal mechanisms of communication and exchange between the associated partners. In addition to providing specific information about the system under investigation, these studies also have helped inform our understanding of genome evolution, mutualism, and innate immunity. In this review we discuss the importance and diversity of nematodes, “omics”' studies in nematode-bacterial systems, and the wider implications of the findings

    Overview of Metagenomics for Marine Biodiversity Research

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    We are in the midst of the fastest growing revolution in molecular biology,perhaps in all of life science, and it appears to be speeding up. We still know very little about the vast diversity of micro-organisms, their metabolic pathways and microbial activity in natural environments. Modern genomic tools are providing deep access to natural microbial diversity and ecology. Interdisciplinary approaches will be required to fully understand microbial ecology by: (1) analysis of genomes, transcriptomes, proteomes and metabolomes and (2) analysis at various levels of individuals, populations, communities and ecosystems. Data gathered is not only theoretical. It holds the promise of practical applications in the control of infectious diseases, in the production of biotechnology goods and services and in environmentalremediation. It is an incredibly exciting time in science for the newer generation of scientists, “loaded” with opportunities. It is an excellent time to develop and apply tools to solve problems of local and global importance.We are in the midst of the fastest growing revolution in molecular biology,perhaps in all of life science, and it appears to be speeding up. We still know very little about the vast diversity of micro-organisms, their metabolic pathways and microbial activity in natural environments. Modern genomic tools are providing deep access to natural microbial diversity and ecology. Interdisciplinary approaches will be required to fully understand microbial ecology by: (1) analysis of genomes, transcriptomes, proteomes and metabolomes and (2) analysis at various levels of individuals, populations, communities and ecosystems. Data gathered is not only theoretical. It holds the promise of practical applications in the control of infectious diseases, in the production of biotechnology goods and services and in environmentalremediation. It is an incredibly exciting time in science for the newer generation of scientists, “loaded” with opportunities. It is an excellent time to develop and apply tools to solve problems of local and global importance

    Wire Tapping

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    Denaturing Polyacrylamide Gel Electrophoresis

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    Thin polyacrylamide gels that contain a high concentration of urea as a denaturant are capable of resolving short (<500 nucleotides) single‐stranded fragments of DNA or RNA that differ in length by as little as one nucleotide. Such gels are uniquely suited for nucleic acid sequence analysis, which is required, for instance, for all footprinting protocols. Thicker gels are often used to purify oligonucleotides. This appendix describes the pouring, running, and processing of a typical sequencing gel, which is 40 cm long with a uniform thickness of 0.4 mm, containing 7 M urea and 4% to 8% acrylamide.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143785/1/cpnca03b.pd

    The Wolbachia Genome of Brugia malayi: Endosymbiont Evolution within a Human Pathogenic Nematode

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    Complete genome DNA sequence and analysis is presented for Wolbachia, the obligate alpha-proteobacterial endosymbiont required for fertility and survival of the human filarial parasitic nematode Brugia malayi. Although, quantitatively, the genome is even more degraded than those of closely related Rickettsia species, Wolbachia has retained more intact metabolic pathways. The ability to provide riboflavin, flavin adenine dinucleotide, heme, and nucleotides is likely to be Wolbachia's principal contribution to the mutualistic relationship, whereas the host nematode likely supplies amino acids required for Wolbachia growth. Genome comparison of the Wolbachia endosymbiont of B. malayi (wBm) with the Wolbachia endosymbiont of Drosophila melanogaster (wMel) shows that they share similar metabolic trends, although their genomes show a high degree of genome shuffling. In contrast to wMel, wBm contains no prophage and has a reduced level of repeated DNA. Both Wolbachia have lost a considerable number of membrane biogenesis genes that apparently make them unable to synthesize lipid A, the usual component of proteobacterial membranes. However, differences in their peptidoglycan structures may reflect the mutualistic lifestyle of wBm in contrast to the parasitic lifestyle of wMel. The smaller genome size of wBm, relative to wMel, may reflect the loss of genes required for infecting host cells and avoiding host defense systems. Analysis of this first sequenced endosymbiont genome from a filarial nematode provides insight into endosymbiont evolution and additionally provides new potential targets for elimination of cutaneous and lymphatic human filarial disease

    Diversifying selection and host adaptation in two endosymbiont genomes

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    Background: The endosymbiont Wolbachia pipientis infects a broad range of arthropod and filarial nematode hosts. These diverse associations form an attractive model for understanding host: symbiont coevolution. Wolbachia's ubiquity and ability to dramatically alter host reproductive biology also form the foundation of research strategies aimed at controlling insect pests and vector-borne disease. The Wolbachia strains that infect nematodes are phylogenetically distinct, strictly vertically transmitted, and required by their hosts for growth and reproduction. Insects in contrast form more fluid associations with Wolbachia. In these taxa, host populations are most often polymorphic for infection, horizontal transmission occurs between distantly related hosts, and direct fitness effects on hosts are mild. Despite extensive interest in the Wolbachia system for many years, relatively little is known about the molecular mechanisms that mediate its varied interactions with different hosts. We have compared the genomes of the Wolbachia that infect Drosophila melanogaster, wMel and the nematode Brugia malayi, wBm to that of an outgroup Anaplasma marginale to identify genes that have experienced diversifying selection in the Wolbachia lineages. The goal of the study was to identify likely molecular mechanisms of the symbiosis and to understand the nature of the diverse association across different hosts. Results: The prevalence of selection was far greater in wMel than wBm. Genes contributing to DNA metabolism, cofactor biosynthesis, and secretion were positively selected in both lineages. In wMel there was a greater emphasis on DNA repair, cell division, protein stability, and cell envelope synthesis. Conclusion: Secretion pathways and outer surface protein encoding genes are highly affected by selection in keeping with host: parasite theory. If evidence of selection on various cofactor molecules reflects possible provisioning, then both insect as well as nematode Wolbachia may be providing substances to hosts. Selection on cell envelope synthesis, DNA replication and repair machinery, heat shock, and two component switching suggest strategies insect Wolbachia may employ to cope with diverse host and intra-host environments

    Lipoprotein biosynthesis as a target for anti-Wolbachia treatment of filarial nematodes

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    <p>Abstract</p> <p>Background</p> <p>Lymphatic filariasis and onchocerciasis are debilitating diseases caused by filarial nematodes. Disease pathogenesis is induced by inflammatory responses following the death of the parasite. <it>Wolbachia </it>endosymbionts of filariae are potent inducers of innate and adaptive inflammation and bacterial lipoproteins have been identified as the ligands that bind toll-like receptors (TLR) 2 and TLR6. Lipoproteins are important structural and functional components of bacteria and therefore enzymes involved in <it>Wolbachia </it>lipoprotein biosynthesis are potential chemotherapeutic targets.</p> <p>Results</p> <p>Globomycin, a signal peptidase II (LspA) inhibitor, has activity against Gram-negative bacteria and a putative <it>lspA </it>gene has been identified from the <it>Wolbachia </it>genome of <it>Brugia malayi </it>(<it>w</it>Bm). The amino acids required for function are strictly conserved and functionality was verified by complementation tests in a temperature-sensitive <it>Escherichia coli lspA </it>mutant. Also, transformation of wild type <it>E. coli </it>with <it>Wolbachia lspA </it>conferred significant globomycin resistance. A cell-based screen has been developed utilizing a <it>Wolbachia</it>-containing <it>Aedes albopictus </it>cell line to assay novel compounds active against <it>Wolbachia</it>. Globomycin was screened using this assay, which resulted in a dose-dependent reduction in <it>Wolbachia </it>load. Furthermore, globomycin was also effective in reducing the motility and viability of adult <it>B. malayi in vitro</it>.</p> <p>Conclusions</p> <p>These studies validate lipoprotein biosynthesis as a target in an organism for which no genetic tools are available. Further studies to evaluate drugs targeting this pathway are underway as part of the A-WOL drug discovery and development program.</p
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