Identifying substrate proteins for GAN1 and Keap1

Abstract only availableGAN1 and Keap1 are proteins characterized by a N-terminal BTB domain and a C-terminal Kelch repeat domain. Both of these domains are protein-protein interaction domains, suggesting that these BTB-Kelch proteins form signaling complexes in cells. Previous work has suggested that BTB-Kelch proteins function as substrate adaptor proteins for Cul3-dependent E3 ubiquitin ligase complexes. The goal of this project was to identify substrate proteins of GAN1 and Keap1. This information will be particularly useful when for understanding Giant Axonal Neuropathy, a sensorimotor disease characterized by excessive accumulation of neurofilaments in neurons that contain mutated GAN1 genes. We used an affinity purification approach to identify candidate substrate proteins for GAN1 and Keap1. Recombinant GAN1 and Keap1 genes containing a C-terminal chitin binding domain (CBD) were inserted into pBabe puro vectors. These vectors were used to generate virus stocks, which were used to infect a microglial cell line, BV-2. Stable cell lines were generated using puromycin selection. A mock-infected cell line was generated in parallel. When the cell lines were confluent, the cells were lysed using a 0.1% SDS RIPA solution and chitin beads were used to precipitate the CBD-tagged proteins. Western blot analyses were performed to determine if the purification of the CBD-tagged proteins was successful. No CBD-tagged proteins were identified in our first pull-down experiment. We are currently reexamining the precipitation protocol and preparing to lysate the same set of cells.Life Sciences Undergraduate Research Opportunity Progra

Tau phosphorylation by GSK-3β promotes tangle-like filament morphology

<p>Abstract</p> <p>Background</p> <p>Neurofibrillary tangles (NFTs) are intraneuronal aggregates associated with several neurodegenerative diseases including Alzheimer's disease. These abnormal accumulations are primarily comprised of fibrils of the microtubule-associated protein tau. During the progression of NFT formation, disperse and non-interacting tau fibrils become stable aggregates of tightly packed and intertwined filaments. Although the molecular mechanisms responsible for the conversion of disperse tau filaments into tangles of filaments are not known, it is believed that some of the associated changes in tau observed in Alzheimer's disease, such as phosphorylation, truncation, ubiquitination, glycosylation or nitration, may play a role.</p> <p>Results</p> <p>We have investigated the effects of tau phosphorylation by glycogen synthase kinase-3β (GSK-3β) on tau filaments in an in vitro model system. We have found that phosphorylation by GSK-3β is sufficient to cause tau filaments to coalesce into tangle-like aggregates similar to those isolated from Alzheimer's disease brain.</p> <p>Conclusion</p> <p>These results suggest that phosphorylation of tau by GSK-3β promotes formation of tangle-like filament morphology. The in vitro cell-free experiments described here provide a new model system to study mechanisms of NFT development. Although the severity of dementia has been found to correlate with the presence of NFTs, there is some question as to the identity of the neurotoxic agents involved. This model system will be beneficial in identifying intermediates or side reaction products that might be neurotoxic.</p

Clinical Nursing and Midwifery Research in Southern and Eastern African Countries

Background: Although nurses provide the majority of healthcare, Africa also has the fewest healthcare workers in the world, including the least number of nurses and midwives in any WHO region. Concurrently, the majority of healthcare research is generated within the United States and Europe, creating evidence for practice that is potentially not applicable in African countries with limited resources and vastly different healthcare problems. Limited information is available regarding what determines which topics are studied in nursing, and even less is known regarding what predicts research trends in African countries. To maximize the use of the limited supply of nurse scientists available, it is important to understand what influences trends in nursing and midwifery research and whether these trends are correlated with what experts consider to be research priorities in a given geographical location and healthcare field. Objective: To address these gaps in the literature and to assist nurse scientists in southern and eastern African countries in directing their research toward those topics with the most critical needs, the aims of this study were to identify 1) what research is currently being conducted, 2) which topics local experts consider to be priorities and furthermore, 3) what influences trends in nursing research. The background and theoretical framework as well as an overview of the dissertation are presented in Chapter 1. Methods: This was accomplished through 1) an environmental scan (including a scoping and a grey literature review in Chapter 2) 2) a Delphi survey of clinical nurse research experts in southeastern African countries (Chapter 3), and 3) a statistical analysis of factors associated with current research topics (Chapter 4). Results: The results of the environmental scan suggest that overall, there is limited clinical nursing and midwifery research and it is less likely to be published in indexed literature. The Delphi survey suggested that critical research priorities in southern and eastern African countries include midwifery and maternal mortality and infectious disease and infection control. Although clinical nurse and midwifery research experts in the region are sensitive to the needs of the region, topics that they rank as critical priorities (such as midwifery and infectious disease) are under-researched. Publication in the grey literature (rather than an indexed source) appears to be associated with whether a topic has major funding, affiliations of the first author (such as international affiliations, or affiliation with a nursing school with a global research focus), and the education level of the first author. Conclusions (Chapter 5): Clinical nursing and midwifery researchers in southern and eastern African countries are generating research that is critical for developing and supporting evidence-based practice but may have difficulty publishing in indexed sources reducing the dissemination and impact of this research. Strategies to assist junior nurse scientists with broader dissemination of their work could include establishing a network of clinical nursing and midwifery researchers in the area for mentoring and resource sharing. Moreover, policy makers and funders from outside the region should consider expert opinion when developing health care policy and funding mechanisms for research to assist with the dissemination of research, reduce waste in research, and to ensure improvement of patient outcomes through relevant, translational research

Viral Receptor Trafficking Regulated by GABARAP

Human cytomegalovirus (HCMV) is a widespread pathogen that can be life-threatening to immune-compromised patients but rarely causes disease in healthy individuals. Previous work using the yeast two-hybrid system found that GABARAP (γ-aminobutyric-acid-receptor-associated-protein) binds to HCMV US27. US27 is similar to human chemokine receptors, but is localized intracellularly instead of on the surface. Here, we examined the US27-GABARAP interaction in human cells and identified a four amino acid motif (WXXL) that mediates GABARAP binding to US27 and its localization to endosomal compartments. Since GABARAP regulates cellular receptor trafficking, these results show that viral US27 is also controlled by a cellular protein

The Figure in Art: Selections from the Gettysburg College Collection

The Figure in Art: Selections from the Gettysburg College Collection is the second annual exhibition curated by students enrolled in the Art History Methods class. This exhibition is an exciting academic endeavor and provides an incredible opportunity for engaged learning, research, and curatorial experience. The eleven student curators are Diane Brennan, Rebecca Duffy, Kristy Garcia, Megan Haugh, Dakota Homsey, Molly Lindberg, Kathya Lopez, Kelly Maguire, Kylie McBride, Carolyn McBrady and Erica Schaumberg. Their research presents a multifaceted view of the representation of figures in various art forms from different periods and cultures.https://cupola.gettysburg.edu/artcatalogs/1017/thumbnail.jp

Pentraxins and Fc Receptor-Mediated Immune Responses

C-reactive protein (CRP) is a member of the pentraxin family of proteins. These proteins are highly conserved over the course of evolution being present as far back as 250 million years ago. Mammalian pentraxins are characterized by the presence of five identical non-covalently linked subunits. Each subunit has a structurally conserved site for calcium-dependent ligand binding. The biological activities of the pentraxins established over many years include the ability to mediate opsonization for phagocytosis and complement activation. Pentraxins have an important role in protection from infection from pathogenic bacteria, and regulation of the inflammatory response. It was recognized early on that some of these functions are mediated by activation of the classical complement pathway through C1q. However, experimental evidence suggested that cellular receptors for pentraxins also play a role in phagocytosis. More recent experimental evidence indicates a direct link between pentraxins and Fc receptors. The Fc receptors were first identified as the major receptors for immunoglobulins. The avidity of the interaction between IgG complexes and Fc receptors is greatly enhanced when multivalent ligands interact with the IgG binding sites and activation of signaling pathways requires Fc receptor crosslinking. Human pentraxins bind and activate human and mouse IgG receptors, FcγRI and FcγRII, and the human IgA receptor, FcαRI. The affinities of the interactions between Fc receptors and pentraxins in solution and on cell surfaces are similar to antibody binding to low affinity Fc receptors. Crystallographic and mutagenesis studies have defined the structural features of these interactions and determined the stoichiometry of binding as one-to-one. Pentraxin aggregation or binding to multivalent ligands increases the avidity of binding and results in activation of these receptors for phagocytosis and cytokine synthesis. This review will discuss the structural and functional characteristics of pentraxin Fc receptor interactions and their implications for host defense and inflammation

Influence of Parenting Practices on Eating Behaviors of Early Adolescents during Independent Eating Occasions: Implications for Obesity Prevention

Among early adolescents (10–14 years), poor diet quality along with physical inactivity can contribute to an increased risk of obesity and associated biomarkers for chronic disease. Approximately one-third of United States (USA) children in this age group are overweight or obese. Therefore, attention to factors affecting dietary intake as one of the primary contributors to obesity is important. Early adolescents consume foods and beverages during eating occasions that occur with and without parental supervision. Parents may influence eating behaviors of early adolescents during eating occasions when they are present or during independent eating occasions by engaging in practices that affect availability of foods and beverages, and through perceived normative beliefs and expectations for intake. Therefore, the purpose of this article was to describe the influence of parenting practices on eating behaviors in general and when specifically applied to independent eating occasions of early adolescents. This information may be helpful to inform parenting interventions targeting obesity prevention among early adolescents focusing on independent eating occasions

Addressing Research Needs in the Field of Plant Virus Ecology by Defining Knowledge Gaps and Developing Wild Dicot Study Systems

Viruses are ubiquitous within all habitats that support cellular life and represent the most important emerging infectious diseases of plants. Despite this, it is only recently that we have begun to describe the ecological roles of plant viruses in unmanaged systems and the influence of ecosystem properties on virus evolution. We now know that wild plants frequently harbor infections by diverse virus species, but much remains to be learned about how viruses influence host traits and how hosts influence virus evolution and vector interactions. To identify knowledge gaps and suggest avenues for alleviating research deficits, we performed a quantitative synthesis of a representative sample of virus ecology literature, developed criteria for expanding the suite of pathosystems serving as models, and applied these criteria through a case study. We found significant gaps in the types of ecological systems studied, which merit more attention. In particular, there is a strong need for a greater diversity of logistically tractable, wild dicot perennial study systems suitable for experimental manipulations of infection status. Based on criteria developed from our quantitative synthesis, we evaluated three California native dicot perennials typically found in Mediterranean-climate plant communities as candidate models: Cucurbita foetidissima (buffalo gourd), Cucurbita palmata (coyote gourd), and Datura wrightii (sacred thorn-apple). We used Illumina sequencing and network analyses to characterize viromes and viral links among species, using samples taken from multiple individuals at two different reserves. We also compared our Illumina workflow with targeted RT-PCR detection assays of varying costs. To make this process accessible to ecologists looking to incorporate virology into existing studies, we describe our approach in detail and discuss advantages and challenges of different protocols. We also provide a bioinformatics workflow based on open-access tools with graphical user interfaces. Our study provides evidence that dicot perennials in xeric habitats support multiple, asymptomatic infections by viruses known to be pathogenic in related crop hosts. Quantifying the impacts of these interactions on plant performance and virus epidemiology in our logistically tractable host systems will provide fundamental information about plant virus ecology outside of crop environments

Parents\u27 Calcium Knowledge Is Associated with Parental Practices to Promote Calcium Intake Among Parents of Early Adolescent Children

The study reported here aimed to identify the relationship of parents\u27 calcium knowledge with diet-related parental practices and determinants of calcium knowledge. A cross-sectional survey was conducted measuring parental practices, calcium knowledge, and demographics. A convenience sample of 599 racially/ethnically diverse parents of children 10-13y completed questionnaires. Higher education and having a daughter were associated with higher calcium knowledge; being Asian or Hispanic and born outside the U.S. were associated with lower calcium knowledge. Parents with greater calcium knowledge were more likely to engage in healthy parenting practices. These factors may be important considerations for Extension educators in nutrition education

Exploring the metabolic network of the epidemic pathogen Burkholderia cenocepacia J2315 via genome-scale reconstruction

<p>Abstract</p> <p>Background</p> <p><it>Burkholderia cenocepacia </it>is a threatening nosocomial epidemic pathogen in patients with cystic fibrosis (CF) or a compromised immune system. Its high level of antibiotic resistance is an increasing concern in treatments against its infection. Strain <it>B. cenocepacia </it>J2315 is the most infectious isolate from CF patients. There is a strong demand to reconstruct a genome-scale metabolic network of <it>B. cenocepacia </it>J2315 to systematically analyze its metabolic capabilities and its virulence traits, and to search for potential clinical therapy targets.</p> <p>Results</p> <p>We reconstructed the genome-scale metabolic network of <it>B. cenocepacia </it>J2315. An iterative reconstruction process led to the establishment of a robust model, <it>i</it>KF1028, which accounts for 1,028 genes, 859 internal reactions, and 834 metabolites. The model <it>i</it>KF1028 captures important metabolic capabilities of <it>B. cenocepacia </it>J2315 with a particular focus on the biosyntheses of key metabolic virulence factors to assist in understanding the mechanism of disease infection and identifying potential drug targets. The model was tested through BIOLOG assays. Based on the model, the genome annotation of <it>B. cenocepacia </it>J2315 was refined and 24 genes were properly re-annotated. Gene and enzyme essentiality were analyzed to provide further insights into the genome function and architecture. A total of 45 essential enzymes were identified as potential therapeutic targets.</p> <p>Conclusions</p> <p>As the first genome-scale metabolic network of <it>B. cenocepacia </it>J2315, <it>i</it>KF1028 allows a systematic study of the metabolic properties of <it>B. cenocepacia </it>and its key metabolic virulence factors affecting the CF community. The model can be used as a discovery tool to design novel drugs against diseases caused by this notorious pathogen.</p