120 research outputs found

    Cell autonomous regulation of herpes and influenza virus infection by the circadian clock.

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    Viruses are intracellular pathogens that hijack host cell machinery and resources to replicate. Rather than being constant, host physiology is rhythmic, undergoing circadian (∼24 h) oscillations in many virus-relevant pathways, but whether daily rhythms impact on viral replication is unknown. We find that the time of day of host infection regulates virus progression in live mice and individual cells. Furthermore, we demonstrate that herpes and influenza A virus infections are enhanced when host circadian rhythms are abolished by disrupting the key clock gene transcription factor Bmal1. Intracellular trafficking, biosynthetic processes, protein synthesis, and chromatin assembly all contribute to circadian regulation of virus infection. Moreover, herpesviruses differentially target components of the molecular circadian clockwork. Our work demonstrates that viruses exploit the clockwork for their own gain and that the clock represents a novel target for modulating viral replication that extends beyond any single family of these ubiquitous pathogens.A.B.R. acknowledges funding from the Wellcome Trust (083643/Z/07/Z, 100333/Z/12/Z and 100574/Z/12/Z), the European Research Council (ERC Starting Grant No. 281348, MetaCLOCK), the EMBO Young Investigators Programme, the Lister Institute of Preventative Medicine and the Medical Research Council (MRC_MC_UU_12012/5). A.D.N acknowledges funding from the People Programme (Marie Curie Actions) of the European Union Seventh Framework Programme (FP7/2007-2013; REA grant agreement 627630). We thank L. Ansel-Bollepalli for assistance with animal breeding, I. Robinson for assistance with pilot animal experiments, A. Snijders and H. Flynn (Francis Crick Institute Proteomics Core) for help with proteomics work, Cambridge NIHR BRC Cell Phenotyping Hub for flow cytometry assistance, A. Miyawaki (RIKEN Brain Science Institute, Japan) for Fucci2 lentiviral vectors, and H. Coleman, J. May and M. Jain for helpful discussions. We thank Prof J. Bass (Northwestern University, USA) for Bmal-/- mouse embryonic fibroblasts used in preliminary experiments, and N. Heaton and P. Palese (Icahn School of Medicine at Mount Sinai, USA) for PB2::Gaussia luciferase IAV (PR8 PB2::GLUC).This is the author accepted manuscript. The final version is available from the National Academy of Sciences via http://dx.doi.org/10.1073/pnas.160189511

    Temperature-sensitive revertants

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    About 50% of a series of non-temperature-sensitive, spontaneously revertable auxotrophs of Escherichia coli showed temperature-sensitive revertants when the selection was at 25[deg] rather than at 37[deg]. This procedure provides a simple device to select temperature-sensitive mutants.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33510/1/0000007.pd

    Functional divergence in the role of N-linked glycosylation in smoothened signaling

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    The G protein-coupled receptor (GPCR) Smoothened (Smo) is the requisite signal transducer of the evolutionarily conserved Hedgehog (Hh) pathway. Although aspects of Smo signaling are conserved from Drosophila to vertebrates, significant differences have evolved. These include changes in its active sub-cellular localization, and the ability of vertebrate Smo to induce distinct G protein-dependent and independent signals in response to ligand. Whereas the canonical Smo signal to Gli transcriptional effectors occurs in a G protein-independent manner, its non-canonical signal employs Gαi. Whether vertebrate Smo can selectively bias its signal between these routes is not yet known. N-linked glycosylation is a post-translational modification that can influence GPCR trafficking, ligand responsiveness and signal output. Smo proteins in Drosophila and vertebrate systems harbor N-linked glycans, but their role in Smo signaling has not been established. Herein, we present a comprehensive analysis of Drosophila and murine Smo glycosylation that supports a functional divergence in the contribution of N-linked glycans to signaling. Of the seven predicted glycan acceptor sites in Drosophila Smo, one is essential. Loss of N-glycosylation at this site disrupted Smo trafficking and attenuated its signaling capability. In stark contrast, we found that all four predicted N-glycosylation sites on murine Smo were dispensable for proper trafficking, agonist binding and canonical signal induction. However, the under-glycosylated protein was compromised in its ability to induce a non-canonical signal through Gαi, providing for the first time evidence that Smo can bias its signal and that a post-translational modification can impact this process. As such, we postulate a profound shift in N-glycan function from affecting Smo ER exit in flies to influencing its signal output in mice

    Identification of Homogentisate Dioxygenase as a Target for Vitamin E Biofortification in Oilseeds

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    Soybean (Glycine max) is a major plant source of protein and oil and produces important secondary metabolites beneficial for human health. As a tool for gene function discovery and improvement of this important crop, a mutant population was generated using fast neutron irradiation. Visual screening of mutagenized seeds identified a mutant line, designated MO12, which produced brown seeds as opposed to the yellow seeds produced by the unmodified Williams 82 parental cultivar. Using forward genetic methods combined with comparative genome hybridization analysis, we were able to establish that deletion of the GmHGO1 gene is the genetic basis of the brown seeded phenotype exhibited by the MO12 mutant line. GmHGO1 encodes a homogentisate dioxygenase (HGO), which catalyzes the committed enzymatic step in homogentisate catabolism. This report describes to our knowledge the first functional characterization of a plant HGO gene, defects of which are linked to the human genetic disease alkaptonuria. We show that reduced homogentisate catabolism in a soybean HGO mutant is an effective strategy for enhancing the production of lipid-soluble antioxidants such as vitamin E, as well as tolerance to herbicides that target pathways associated with homogentisate metabolism. Furthermore, this work demonstrates the utility of fast neutron mutagenesis in identifying novel genes that contribute to soybean agronomic traits

    A critical review of the evidence for nurses as information providers to cancer patients

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    To review evidence on the role of oncology nurses in the provision of information to cancer patients and to delineate evidence-based implications for clinical practice and research.Provision of information is central for the empowerment of patients to participate in their care. There is not enough evidence regarding the nursing role in the information delivery process in cancer patients.Descriptive literature review.From January 1990–2008, databases searched included Medline, CINAHL, PubMed, CancerLit and the Cochrane Library. Original research articles addressing the role of nurses in information delivery were included. We explored evidence on: (1) the effectiveness of nurses as information providers, (2) the way patients evaluate nurses’ input to information delivery, (3) the extent to which nurses contribute to information delivery to cancer patients and (4) the types of information provided by nurses.The most important findings were: (1) nurses’ role as information providers for cancer patients is prominent, especially after the initiation of treatment, (2) specialist nurses are very effective in providing information, (3) no clear evidence exists on how nurses compare with other health-care professionals as information providers and (4) some evidence exists that patients may prefer nurses as information providers at specific times in their treatment and especially in regards to symptom management.Well-designed studies provide some evidence that nurses are effective as information providers to cancer patients. Specifically, oncology nurses are able to provide information of both high quality and of appropriate quantity and to assist individuals to interpret information provided by others.Oncology nurses should be specifically educated and prepared to offer explicit, practical and timely information and they should be trained in interpersonal communication skills, which will increase their ability to comprehend patient information needs.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79127/1/j.1365-2702.2009.02954.x.pd

    Low-risk susceptibility alleles in 40 human breast cancer cell lines

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    Background: Low-risk breast cancer susceptibility alleles or SNPs confer only modest breast cancer risks ranging from just over 1.0 to 1.3 fold. Yet, they are common among most populations and therefore are involved in the development of essentially all breast cancers. The mechanism by which the low-risk SNPs confer breast cancer risks is currently unclear. The breast cancer association consortium BCAC has hypothesized that the low-risk SNPs modulate expression levels of nearby located genes. Methods: Genotypes of five low-risk SNPs were determined for 40 human breast cancer cell lines, by direct sequencing of PCR-amplified genomic templates. We have analyzed expression of the four genes that are located nearby the low-risk SNPs, by using real-time RT-PCR and Human Exon microarrays. Results: The SNP genotypes and additional phenotypic data on the breast cancer cell lines are presented. We did not detect any effect of the SNP genotypes on expression levels of the nearby-located genes MAP3K1, FGFR2, TNRC9 and LSP1. Conclusion: The SNP genotypes provide a base line for functional studies in a well-characterized cohort of 40 human breast cancer cell lines. Our expression analyses suggest that a putative disease mechanism through gene expression modulation is not operative in breast cancer cell lines

    Monitoring of Farm-Level Antimicrobial Use to Guide Stewardship: Overview of Existing Systems and Analysis of Key Components and Processes

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    peer-reviewedThe acknowledgment of antimicrobial resistance (AMR) as a major health challenge in humans, animals and plants, has led to increased efforts to reduce antimicrobial use (AMU). To better understand factors influencing AMR and implement and evaluate stewardship measures for reducing AMU, it is important to have sufficiently detailed information on the quantity of AMU, preferably at the level of the user (farmer, veterinarian) and/or prescriber or provider (veterinarian, feed mill). Recently, several countries have established or are developing systems for monitoring AMU in animals. The aim of this publication is to provide an overview of known systems for monitoring AMU at farm-level, with a descriptive analysis of their key components and processes. As of March 2020, 38 active farm-level AMU monitoring systems from 16 countries were identified. These systems differ in many ways, including which data are collected, the type of analyses conducted and their respective output. At the same time, they share key components (data collection, analysis, benchmarking, and reporting), resulting in similar challenges to be faced with similar decisions to be made. Suggestions are provided with respect to the different components and important aspects of various data types and methods are discussed. This overview should provide support for establishing or working with such a system and could lead to a better implementation of stewardship actions and a more uniform communication about and understanding of AMU data at farm-level. Harmonization of methods and processes could lead to an improved comparability of outcomes and less confusion when interpreting results across systems. However, it is important to note that the development of systems also depends on specific local needs, resources and aims

    New genetic loci link adipose and insulin biology to body fat distribution.

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    Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
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