Publications by authors named "Jeremy Brownlie"

Plant pathogens are a major reason of reduced crop productivity and may lead to a shortage of food for both human and animal consumption. Although chemical control remains the main method to reduce foliar fungal disease incidence, frequent use can lead to loss of susceptibility in the fungal population. Furthermore, over-spraying can cause environmental contamination and poses a heavy financial burden on growers.

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Background: Peripherally inserted central catheters are susceptible to microbial colonisation and subsequent biofilm formation, leading to central line-associated bloodstream infection, a serious peripherally inserted central catheter-related complication. Next-generation peripherally inserted central catheter biomaterials, such as hydrophobic materials (e.g.

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Neurogenesis is a persistent and essential feature of the adult mammalian hippocampus. Granular neurons generated from resident pools of stem or progenitor cells provide a mechanism for the formation and consolidation of new memories. Regulation of hippocampal neurogenesis is complex and multifaceted, and numerous signaling pathways converge to modulate cell proliferation, apoptosis, and clearance of cellular debris, as well as synaptic integration of newborn immature neurons.

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Live-cell flow cytometry is increasingly used among cell biologists to quantify biological processes in a living cell culture. This protocol describes a method whereby live-cell flow cytometry is extended upon to analyze the multiple functions of P2X7 receptor activation in real-time. Using a time module installed on a flow cytometer, live-cell functionality can be assessed and plotted over a given time period to explore the kinetics of calcium influx, transmembrane pore formation, and phagocytosis.

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infections can present different phenotypes in hosts, including different forms of reproductive manipulation and antiviral protection, which may influence infection dynamics within host populations. In populations of two distinct strains coexist, each manipulating host reproduction: strain PanCI causes cytoplasmic incompatibility (CI), whereas strain PanMK causes male killing (MK). CI occurs when a -infected male mates with a female not infected with a compatible type of , leading to nonviable offspring.

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Wolbachia are endosymbiotic bacteria present in a wide range of invertebrates. Although their dramatic effects on host reproductive biology have been well studied, little is known about the effects of Wolbachia on the learning and memory capacity (LMC) of hosts, despite their distribution in the host nervous system, including brain. In this study, we found that Wolbachia infection significantly enhanced LMC in both Drosophila melanogaster and D.

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Identifying the signaling mechanisms that regulate adult neurogenesis is essential to understanding how the brain may respond to neuro-inflammatory events. P2X7 receptors can regulate pro-inflammatory responses, and in addition to their role as cation channels they can trigger cell death and mediate phagocytosis. How P2X7 receptors may regulate adult neurogenesis is currently unclear.

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Background: The formation of biofilms and subsequent encasement of bacterial cells in a complex matrix can enhance resistance to antimicrobials and sterilizing agents making these organisms difficult to eradicate and control. The aim of this study was to evaluate and compare the capacity of 40 E. coli O26 isolates of enterohemorrhagic E.

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Transposable elements (TEs) have been recognized as potentially powerful drivers of genomic evolutionary change, but factors affecting their mobility and regulation remain poorly understood. Chaperones such as Hsp90 buffer environmental perturbations by regulating protein conformation, but are also part of the PIWI-interacting RNA pathway, which regulates genomic instability arising from mobile TEs in the germline. Stress-induced mutagenesis from TE movement could thus arise from functional trade-offs in the dual roles of Hsp90.

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Wolbachia are maternally transmitted intracellular bacterial symbionts that infect approximately 40% of all insect species. Though several strains of Wolbachia naturally infect Drosophila melanogaster and provide resistance against viral pathogens, or provision metabolites during periods of nutritional stress, one virulent strain, wMelPop, reduces fly lifespan by half, possibly as a consequence of over-replication. While the mechanisms that allow wMelPop to over-replicate are still of debate, a unique tandem repeat locus in the wMelPop genome that contains eight genes, referred to as the "Octomom" locus has been identified and is thought to play an important regulatory role.

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Elevated levels of reactive oxygen species (ROS) provide protection against virus-induced mortality in Drosophila. In addition to contributing to oxidative stress, ROS are known to activate a number of signalling pathways including the extracellular signal-regulated kinases (ERK) signalling cascade. It was recently shown that ERK signalling is important for resistance against viral replication and invasion in cultured Drosophila cells and the gut epithelium of adult flies.

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Hyaluronic acid (HA) is a polysaccharide found in the extracellular matrix of vertebrate epithelial, neural and connective tissues. Due to the high moisture retention, biocompatibility and viscoelasticity properties of this polymer, HA has become an important component of major pharmaceutical, biomedical and cosmetic products with high commercial value worldwide. Currently, large scale production of HA involves extraction from animal tissues as well as the use of bacterial expression systems in Streptococci.

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To investigate the molecular mechanisms of cytoplasmic incompatibility (CI) induced by Wolbachia bacteria in Drosophila melanogaster, we applied an isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic assay to identify differentially expressed proteins extracted from spermathecae and seminal receptacles (SSR) of uninfected females mated with either 1-day-old Wolbachia-uninfected (1T) or infected males (1W) or 5-day-old infected males (5W). In total, 1317 proteins were quantified; 83 proteins were identified as having at least a 1.5-fold change in expression when 1W was compared with 1T.

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Wolbachia bacteria are endosymbionts that infect approximately 40% of all insect species and are best known for their ability to manipulate host reproductive systems. Though the effect Wolbachia infection has on somatic tissues is less well understood, when present in cells of the adult Drosophila melanogaster brain, Wolbachia exerts an influence over behaviors related to olfaction. Here, we show that a strain of Wolbachia influences male aggression in flies, which is critically important in mate competition.

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Wolbachia mediates antiviral protection in insect hosts and is being developed as a potential biocontrol agent to reduce the spread of insect-vectored viruses. Definition of the molecular mechanism that generates protection is important for understanding the tripartite interaction between host insect, Wolbachia, and virus. Elevated oxidative stress was previously reported for a mosquito line experimentally infected with Wolbachia, suggesting that oxidative stress is important for Wolbachia-mediated antiviral protection.

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Most strains of the widespread endosymbiotic bacterium Wolbachia pipientis are benign or behave as reproductive parasites. The pathogenic strain wMelPop is a striking exception, however: it overreplicates in its insect hosts and causes severe life shortening. The mechanism of this pathogenesis is currently unknown.

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Background: The endosymbiont Wolbachia pipientis causes diverse and sometimes dramatic phenotypes in its invertebrate hosts. Four Wolbachia strains sequenced to date indicate that the constitution of the genome is dynamic, but these strains are quite divergent and do not allow resolution of genome diversification over shorter time periods. We have sequenced the genome of the strain wBol1-b, found in the butterfly Hypolimnas bolina, which kills the male offspring of infected hosts during embyronic development and is closely related to the non-male-killing strain wPip from Culex pipiens.

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Wolbachia, a maternally transmitted endosymbiont of insects, is increasingly being seen as an effective biological control agent that can interfere with transmission of pathogens, including dengue virus. However, the mechanism of antiviral protection is not well understood. The density and distribution of Wolbachia in host tissues have been implicated as contributing factors by previous studies with both mosquitoes and flies.

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The outcome of microbial infection of insects is dependent not only on interactions between the host and pathogen, but also on the interactions between microbes that co-infect the host. Recently the maternally inherited endosymbiotic bacteria Wolbachia has been shown to protect insects from a range of microbial and eukaryotic pathogens. Mosquitoes experimentally infected with Wolbachia have upregulated immune responses and are protected from a number of pathogens including viruses, bacteria, Plasmodium and filarial nematodes.

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