Membrane localization of the NlpC/P60 family protein EGL-26 correlates with regulation of vulval cell morphogenesis in Caenorhabditis elegans

AbstractVulval morphogenesis in Caenorhabditis elegans generates a stack of toroidal cells enclosing a tubular lumen. Mutation of egl-26 is associated with malformation of vulF, the most dorsal toroid in the stack, resulting in a blocked lumen and an egg-laying defect. Here we present evidence that vulF retains the expected gene expression pattern, functions in signaling to the uterus and retains proper polarity when egl-26 is mutated, all suggesting that mutation of egl-26 specifically results in aberrant morphogenesis as opposed to abnormal fate specification. Recent computational analysis indicates that EGL-26, which was previously characterized as novel, belongs to the LRAT (lecithin retinol acyltransferase) subfamily of the NlpC/P60 superfamily of catalytic proteins. Via site-directed mutagenesis, we demonstrate a requirement of the putative catalytic residues for EGL-26 function in vivo. We also show that mutation of conserved serine 275 perturbs the apical membrane localization and the function of the EGL-26 protein. Additional mutagenesis of this residue suggests that EGL-26 attains its membrane localization via a mechanism distinct from that of LRAT

Gulf of Mexico Regional Collaborative Final Report

This report presents the results of the Gulf of Mexico Regional Collaborative (GoMRC), a year-long project funded by NASA. The GoMRC project was organized around end user outreach activities, a science applications team, and a team for information technology (IT) development. Key outcomes are summarized below for each of these areas. End User Outreach Successfully engaged federal and state end users in project planning and feedback With end user input, defined needs and system functional requirements Conducted demonstration to End User Advisory Committee on July 9, 2007 and presented at Gulf of Mexico Alliance (GOMA) meeting of Habitat Identification committee Conducted significant engagement of other end user groups, such as the National Estuary Programs (NEP), in the Fall of 2007 Established partnership with SERVIR and Harmful Algal Blooms Observing System (HABSOS) programs and initiated plan to extend HABs monitoring and prediction capabilities to the southern Gulf. Established a science and technology working group with Mexican institutions centered in the State of Veracruz. Key team members include the Federal Commission for the Protection Against Sanitary Risks (COFEPRIS), the Ecological Institute (INECOL) a unit of the National Council for science and technology (CONACYT), the Veracruz Aquarium (NOAA’s first international Coastal Ecology Learning Center) and the State of Veracruz. The Mexican Navy (critical to coastal studies in the Southern Gulf) and other national and regional entities have also been engaged. Training on use of SERVIR portal planned for Fall 2007 in Veracruz, Mexico Science Applications Worked with regional scientists to produce conceptual models of submerged aquatic vegetation (SAV) ecosystems Built a logical framework and tool for ontological modeling of SAV and HABs Created online guidance for SAV restoration planning Created model runs which link potential future land use trends, runoff and SAV viability Analyzed SAV cover change at five other bays in the Gulf of Mexico to demonstrate extensibility of the analytical tools Initiated development of a conceptual model for understanding the causes and effects of HABs in the Gulf of Mexico IT Tool Development Established a website with the GoMRC web-based tools at www.gomrc.org Completed development of an ArcGIS-based decision support tool for SAV restoration prioritization decisions, and demonstrated its use in Mobile Bay Developed a web-based application, called Conceptual Model Explorer (CME), that enables non-GIS users to employ the prioritization model for SAV restoration Created CME tool enabling scientists to view existing, and create new, ecosystem conceptual models which can be used to document cause-effect relationships within coastal ecosystems, and offer guidance on management solutions. Adapted the science-driven advanced web search engine, Noesis, to focus on an initial set of coastal and marine resource issues, including SAV and HABs Incorporated map visualization tools with initial data layers related to coastal wetlands and SAV

Increased Intestinal Permeability Correlates with Sigmoid Mucosa alpha-Synuclein Staining and Endotoxin Exposure Markers in Early Parkinson's Disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder of aging. The pathological hallmark of PD is neuronal inclusions termed Lewy bodies whose main component is alpha-synuclein protein. The finding of these Lewy bodies in the intestinal enteric nerves led to the hypothesis that the intestine might be an early site of PD disease in response to an environmental toxin or pathogen. One potential mechanism for environmental toxin(s) and proinflammatory luminal products to gain access to mucosal neuronal tissue and promote oxidative stress is compromised intestinal barrier integrity. However, the role of intestinal permeability in PD has never been tested. We hypothesized that PD subjects might exhibit increased intestinal permeability to proinflammatory bacterial products in the intestine. To test our hypothesis we evaluated intestinal permeability in subjects newly diagnosed with PD and compared their values to healthy subjects. In addition, we obtained intestinal biopsies from both groups and used immunohistochemistry to assess bacterial translocation, nitrotyrosine (oxidative stress), and alpha-synuclein. We also evaluated serum markers of endotoxin exposure including LPS binding protein (LBP). Our data show that our PD subjects exhibit significantly greater intestinal permeability (gut leakiness) than controls. In addition, this intestinal hyperpermeability significantly correlated with increased intestinal mucosa staining for E. coli bacteria, nitrotyrosine, and alpha-synuclein as well as serum LBP levels in PD subjects. These data represent not only the first demonstration of abnormal intestinal permeability in PD subjects but also the first correlation of increased intestinal permeability in PD with intestinal alpha-synuclein (the hallmark of PD), as well as staining for gram negative bacteria and tissue oxidative stress. Our study may thus shed new light on PD pathogenesis as well as provide a new method for earlier diagnosis of PD and suggests potential therapeutic targets in PD subjects.Clinicaltrials.gov NCT01155492

Non-Lytic, Actin-Based Exit of Intracellular Parasites from C. elegans Intestinal Cells

The intestine is a common site for invasion by intracellular pathogens, but little is known about how pathogens restructure and exit intestinal cells in vivo. The natural microsporidian parasite N. parisii invades intestinal cells of the nematode C. elegans, progresses through its life cycle, and then exits cells in a transmissible spore form. Here we show that N. parisii causes rearrangements of host actin inside intestinal cells as part of a novel parasite exit strategy. First, we show that N. parisii infection causes ectopic localization of the normally apical-restricted actin to the basolateral side of intestinal cells, where it often forms network-like structures. Soon after this actin relocalization, we find that gaps appear in the terminal web, a conserved cytoskeletal structure that could present a barrier to exit. Reducing actin expression creates terminal web gaps in the absence of infection, suggesting that infection-induced actin relocalization triggers gap formation. We show that terminal web gaps form at a distinct stage of infection, precisely timed to precede spore exit, and that all contagious animals exhibit gaps. Interestingly, we find that while perturbations in actin can create these gaps, actin is not required for infection progression or spore formation, but actin is required for spore exit. Finally, we show that despite large numbers of spores exiting intestinal cells, this exit does not cause cell lysis. These results provide insight into parasite manipulation of the host cytoskeleton and non-lytic escape from intestinal cells in vivo

Robust and persistent reactivation of SIV and HIV by N-803 and depletion of CD8+ cells

Human immunodeficiency virus (HIV) persists indefinitely in individuals with HIV who receive antiretroviral therapy (ART) owing to a reservoir of latently infected cells that contain replication-competent virus1–4. Here, to better understand the mechanisms responsible for latency persistence and reversal, we used the interleukin-15 superagonist N-803 in conjunction with the depletion of CD8+ lymphocytes in ART-treated macaques infected with simian immunodeficiency virus (SIV). Although N-803 alone did not reactivate virus production, its administration after the depletion of CD8+ lymphocytes in conjunction with ART treatment induced robust and persistent reactivation of the virus in vivo. We found viraemia of more than 60 copies per ml in all macaques (n = 14; 100%) and in 41 out of a total of 56 samples (73.2%) that were collected each week after N-803 administration. Notably, concordant results were obtained in ART-treated HIV-infected humanized mice. In addition, we observed that co-culture with CD8+ T cells blocked the in vitro latency-reversing effect of N-803 on primary human CD4+ T cells that were latently infected with HIV. These results advance our understanding of the mechanisms responsible for latency reversal and lentivirus reactivation during ART-suppressed infection

NASA'S SERVIR Gulf of Mexico Project: The Gulf of Mexico Regional Collaborative (GoMRC)

The Gulf of Mexico Regional Collaborative (GoMRC) is a NASA-funded project that has as its goal to develop an integrated, working, prototype IT infrastructure for Earth science data, knowledge and models for the five Gulf U.S. states and Mexico, and to demonstrate its ability to help decision-makers better understand critical Gulf-scale issues. Within this preview, the mission of this project is to provide cross cutting solution network and rapid prototyping capability for the Gulf of Mexico region, in order to demonstrate substantial, collaborative, multi-agency research and transitional capabilities using unique NASA data sets and models to address regional problems. SERVIR Mesoamerica is seen as an excellent existing framework that can be used to integrate observational and GIs data bases, provide a sensor web interface, visualization and interactive analysis tools, archival functions, data dissemination and product generation within a Rapid Prototyping concept to assist decision-makers in better understanding Gulf-scale environmental issues

bZIP transcription factor zip-2 mediates an early response to Pseudomonas aeruginosa infection in Caenorhabditis elegans

Very little is known about how animals discriminate pathogens from innocuous microbes. To address this question, we examined infection-response gene induction in the nematode Caenorhabditis elegans. We focused on genes that are induced in C. elegans by infection with the bacterial pathogen Pseudomonas aeruginosa, but are not induced by an isogenic attenuated gacA mutant. Most of these genes are induced independently of known immunity pathways. We generated a GFP reporter for one of these genes, infection response gene 1 (irg-1), which is induced strongly by wild-type P. aeruginosa strain PA14, but not by other C. elegans pathogens or by other wild-type P. aeruginosa strains that are weakly pathogenic to C. elegans. To identify components of the pathway that induces irg-1 in response to infection, we performed an RNA interference screen of C. elegans transcription factors. This screen identified zip-2, a bZIP transcription factor that is required for inducing irg-1, as well as several other genes, and is important for defense against infection by P. aeruginosa. These data indicate that zip-2 is part of a specialized pathogen response pathway that is induced by virulent strains of P. aeruginosa and provides defense against this pathogen

Non-Human Primate Models of HIV Brain Infection and Cognitive Disorders

Human Immunodeficiency virus (HIV)-associated neurocognitive disorders are a major burden for people living with HIV whose viremia is stably suppressed with antiretroviral therapy. The pathogenesis of disease is likely multifaceted, with contributions from viral reservoirs including the brain, chronic and systemic inflammation, and traditional risk factors including drug use. Elucidating the effects of each element on disease pathogenesis is near impossible in human clinical or ex vivo studies, facilitating the need for robust and accurate non-human primate models. In this review, we describe the major non-human primate models of neuroHIV infection, their use to study the acute, chronic, and virally suppressed infection of the brain, and novel therapies targeting brain reservoirs and inflammation