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UC Riverside Researchers Discover Model Organism For Studying Viruses that Affect Humans
August 18, 2005
Simple nematode has similar virus-fighting mechanism as humans and can be used in research RIVERSIDE, Calif. - www.ucr.edu - Researchers at the University of California, Riverside have discovered that a simple worm, called C. elegans, makes an excellent experimental host for studying some of the most virulent viruses that infect humans. The researchers published their findings in the Aug. 18 issue of the journal Nature in a paper titled, Animal virus replication and RNAi-mediated antiviral silencing in C. elegans. UCR Professor of Plant Pathology Shou-Wei Ding co-authored the paper with Morris Maduro, assistant professor of biology; Feng Li, a graduate student in microbiology; Rui Lu and Hongwei Li, postdoctoral researchers in Ding's laboratory; and research specialists Gina Broitman-Maduro and Wan-Xiang Li. Lu and Maduro are co-first authors of this Nature paper. The National Institutes of Health and the U.S. Department of Agriculture supported the research. The paper reflects a major step forward in the study of how some of the world's most virulent viruses, such as West Nile, SARS, Ebola and Hepatitis C interact with their hosts. "All these viruses are very dangerous and are traditionally studied in animal models, so large-scale genetic studies of the host-virus interaction is very hard to do," said Ding, who works in the Center for Plant Cell Biology at UCR's Institute for Integrative Genome Biology. "Needless to say, we are all very excited to find that this little worm can be used to understand how hosts genetically control viruses." For years researchers throughout the world have studied C. elegans because many aspects of its biology, such as genetics, development and the workings of neurons, mirror the biology of humans. However, no viruses were known to infect the millimeter-long roundworm so it was not used as a model for studying viral infections. The Nature paper now shows that UC Riverside researchers have developed a strain of the worm, C. elegans, in which an animal virus could replicate, allowing them to map the delicate dance of action and reaction between virus and host. The UCR team has shown that virus replication in the worm triggers an antiviral response known as RNA silencing or RNA interference (RNAi). RNAi specifically breaks down the virus' RNA. Virus RNA creates proteins that allow the virus to function. The virus responds by producing a protein acting as a suppressor of RNAi to shut down the host's antiviral response. Virus infection did not occur when the viral RNAi suppressor was made inactive by genetic mutations in the host system. C. elegans' RNAi system is considered a "blanket system," meaning that it has parallels in humans, making the worm model discovered by Ding and his colleagues a valuable tool in studying the way viruses interact with hosts. This tool may speed the discovery of treatments for virus-caused diseases that plague humans. "The RNAi machinery is very similar between humans and C. elegans, and human viruses such as Influenza A virus and HIV are known to produce RNAi suppressors," Ding said. "So now, the question is can we treat human viral diseases using chemical inhibitors of viral RNAi suppressors?" The methods outlined in the Nature paper are now being used to generate additional C. elegans strains for screening chemical compounds that inactivate RNAi suppressors associated with avian flu, HIV and others. University of California, Riverside Related C Elegans Current Events and C Elegans News ArticlesScientists develop worm EEG to test the effects of drugsScientists from the University of Southampton have developed a device which records the brain activity of worms to help test the effects of drugs. CU study suggests link between tumor suppressors and starvation survivalA particular tumor suppressor gene that fights cancer cells does more than clamp down on unabated cell division -- the hallmark of the disease -- it also can help make cells more fit by allowing them to fend off stress, says a University of Colorado Boulder study Finding Nematostella: An ancient sea creatureThere's a new actor on the embryology stage: the starlet sea anemone Nematostella vectensis. Its career is being launched in part by Stowers Institute for Medical Research Associate Investigator Matt Gibson, Ph.D., who is giving it equal billing with what has been his laboratory's leading player, the fruit fly Drosophila melanogaster. Tiny worm sheds light on giant mystery about neuronsScientists have identified a gene that keeps our nerve fibers from clogging up. Researchers in Ken Miller's laboratory at the Oklahoma Medical Research Foundation (OMRF) found that the unc-16 gene of the roundworm Caenorhabditis elegans encodes a gatekeeper that restricts flow of cellular organelles from the cell body to the axon, a long, narrow extension that neurons use for signaling. Worming our way to new treatments for Alzheimer's diseaseAccording to a 2012 World Health Organization report, over 35 million people worldwide currently have dementia, a number that is expected to double by 2030 (66 million) and triple by 2050 (115 million). Alzheimer's disease, the most common form of dementia, has no cure and there are currently only a handful of approved treatments that slow, but do not prevent, the progression of symptoms. Linking insulin to learningRecent work by Harvard researchers demonstrates how the signaling pathway of insulin and insulinlike peptides plays a critical role in helping to regulate learning and memory. Cellular renewal process may underlie benefits of omega fatty acidsA search for genes that change their levels of expression in response to nutrient deprivation has uncovered potential clues to the mechanism underlying the health benefits of omega fatty acids. Researchers find chemical 'switches' for neurodegenerative diseasesBy using a model, researchers at the University of Montreal have identified and "switched off" a chemical chain that causes neurodegenerative diseases such as Huntington's disease, amyotrophic lateral sclerosis and dementia. UC Santa Barbara scientists learn how to unlock the destiny of a cell: A gift for the tin man?Scientists have discovered that breaking a biological signaling system in an embryo allows them to change the destiny of a cell. The findings could lead to new ways of making replacement organs. Understanding the brain by controlling behaviorIn the quest to understand how the brain turns sensory input into behavior, Harvard scientists have crossed a major threshold. Using precisely-targeted lasers, researchers have been able to take over an animal's brain, instruct it to turn in any direction they choose, and even to implant false sensory information, fooling the animal into thinking food was nearby. More C Elegans Current Events and C Elegans News Articles

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C. elegans: A Practical Approach
by Ian A. Hope (Editor)
Caenorhabditis Elegans has been a popular model organism for biological research for over thirty years and has been used to investigate many aspects of animal development, for example apoptosis, the Hox genes, signal transduction pathways, and the development of the nervous system. It has recently taken on new importance with the publication of the entire genome sequence in 1998. The first chapter gives all the basic information on C. elegans required to use it: it's natural history, anatomy, life cycle, development, and evolution. Information on how to obtain, grow, and maintain C. elegans for use as a model system is given in Chapter 4. Chapters 2 and 3 describe the genome project and show how to use genome sequence information by searching the database for homologues using different...
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C. Elegans II
by Donald Riddle (Author)
Studies of the cells and genes of the nematode C. elegans have become a cornerstone of current biology. A classic 1988 Cold Spring Harbor monograph, The Nematode Caenorhabditis elegans, described the basic genetics, anatomy and development of the organism. Now, in that authoritative tradition, comes C. elegans II not a second edition but a book that breaks new ground and defines the current status of the field, providing a detailed molecular explanation of how development is regulated and the nervous system specifies varied aspects of behavior. This volume is a must for any investigator doing worm studies but it has been written and rigorously edited to illuminate for a wider community of investigators in cell and molecular biology who should know how new knowledge of C. elegans relates...
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C. elegans: Methods and Applications (Methods in Molecular Biology)
by Kevin Strange (Editor)
Nonmammalian model organisms have become a cornerstone of systems biology research. Like the Rosetta Stone, which enabled modern scholars to decode ancient Egyptian hieroglyphics, model organisms enable biologists to decipher the genetic code underlying the complex physiological processes common to all life. C. elegans provides a particularly striking example of the experimental utility of model organisms. Genetic, molecular and systems biological characterization of this organism is greatly facilitated by its short life cycle and high rate reproduction, and by the ease with which it can be cultured in the laboratory. C. elegans also has a fully sequenced and well-annotated genome, which is assembled in readily accessible public databases along with virtually all other biological data...
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The Nematode Caenorhabditis Elegans (The Cold Spring Harbor Monograph Series)
by William B Wood (Author)
In 1965 Sydney Brenner chose the free-living nematode Caenorhabditis elegans as a promising model system for a concerted genetic, ultrastructural, and behavioral attack on the development and function of a simple nervous system. Since then, with the help of a growing number of investigators, knowledge about the biology of;the worm; has accumulated at a steadily accelerating pace to the extent that C. elegans is now probably the most completely understood metazoan in terms of anatomy, genetics, development, and behavior. The past few years have seen the completion of two major long-term projects that provide new insights into C. elegans development and lay important groundwork for future investigation: completion of the cell lineages of both sexes, from zygote to adult, and description of...
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C. elegans and Innate Immunity: A proteomic approach
by Srinivasan Ponnuraj (Author), Raja Lakshmi Manickam (Author)
The striking similarities between the innate defenses of vertebrates and invertebrates as well as the amenability of Caenorhabditis elegans for genetic analysis have made this free-living ground nematode a popular model system in the study of bacterial pathogenesis. Although genetic studies have brought new insights, showing the inducibility and pathogen-specificity of the immune response, there is still much to be discovered about the exact mechanisms underlying resistance to infection. In this study a different angle was adopted to study host–pathogen interactions in C. elegans. Given the dynamic nature of an immune response, the proteome of C. elegans was investigated at four different time-points (24, 48, 72, 96 h) after infection with S. typhi, S. typhi Ty21a, C. sakazakii and E....
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Germ Cell Development in C. elegans (Advances in Experimental Medicine and Biology)
by Tim Schedl (Editor)
Germ cells in sexually reproducing metazoa, through the germline lineage, are the route by which genetic material and cytoplasmic constituents are passed from one generation to the next in the continuum of life. Chapters in this book review germ cell development in the model organism Caenorhabditis elegans, discussing the biology, the genetics and the molecular mechanisms for various processes, as well as drawing comparisons with other organisms. Processes discussed include specification of germ cell fate, meiosis, gametogenesis, environmental/ physiological controls, epigenetics and translational control, fertilization and the oocyte-to-embryo transition. This book thus provides a comprehensive picture of the germline lineage and the continuum of life for the worm.
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C. elegans Atlas
by David H. Hall (Author), Zeynep F. Altun (Author)
Derived from the acclaimed online ''WormAtlas,''C. elegans Atlas is a large-format, full-color atlas of the hermaphroditic form of the model organism C. elegans, known affectionately as ''the worm'' by workers in the field. Prepared by the editors of the WormAtlas Consortium, David H. Hall and Zeynep F. Altun, this book combines explanatory text with copious, labeled, color illustrations and electron micrographs of the major body systems of C. elegans. Also included are electron microscopy cross sections of the worm. This laboratory reference is essential for the working worm biologist, at the bench and at the microscope, and provides a superb companion to the C. elegans II monograph. It is also a valuable tool for investigators in the fields of developmental biology, neurobiology,...
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The Neurobiology of C. elegans, Volume 69 (International Review of Neurobiology)
by Eric James Aamodt (Editor)
The Neurobiology of C. elegans assembles together a series of chapters describing the progress researchers have made toward solving some of the major problems in neurobiology with the use of this powerful model organism. The first chapter is an introduction to the anatomy of the C. elegans nervous system. This chapter provides a useful introduction to this system and will help the reader who is less familiar with this system understand the chapters that follow. The next two chapters on learning, conditioning and memory and neuronal specification and differentiation, summarize the current state of the C. elegans field in these two major areas of neurobiology. The remaining chapters describe studies in C. elegans that have provided particularly exciting insights into neurobiology.
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Ay's Neuroanatomy of C. Elegans for Computation
by Theodore B. Achacoso (Author), William S. Yamamoto (Author)
AY's Neuroanatomy of C. elegans for Computation provides the neural circuitry database of the nematode Caenorhabditis elegans, both in printed form and in ASCII files on 5.25-inch diskettes (for use on IBM® and compatible personal computers, Macintosh® computers, and higher level machines). Tables of connections among neuron classes, synapses among individual neurons, gap junctions among neurons, worm cells and their embryonic origin, and synthetically derived neuromuscular connections are presented together with the references from which the data were compiled and edited. Sample data files and source codes of FORTRAN and BASIC programs are provided to illustrate the use of mathematical tools for any researcher or student interested in examining a natural neural network and discovering...
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Evolution in Health and Disease
by Stephen C. Stearns (Author), Jacob C. Koella (Author)
In this fully revised and updated edition, the editors have integrated a completely new set of contributions from the leading researchers in the field to describe the latest research in evolutionary medicine, providing a fresh summary of this rapidly expanding field 10 years after its predecessor was first compiled. It continues to adopt a broad approach to the subject, drawing on medically relevant research from evolutionary genetics, human behavioral ecology, evolutionary microbiology (especially experimental evolution of virulence and resistance), the evolution of aging and degenerative disease, and other aspects of biology or medicine where evolutionary approaches make important contributions.
Evolution in Health and Disease describes how evolutionary thinking gives valuable...
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