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[
Worm Breeder's Gazette,
1994]
mab-3 YAC rescue David Zarkower, Mario de Bono, and Jonathan Hodgkin MRC Laboratory of Molecular Biology, Cambridge, England
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[
BMC Biol,
2018]
David Weinkove is an associate professor at Durham University, UK, studying host-microbe interactions in the model organism Caenorhabditis elegans. David has been focusing on the way microbes affect the physiology of their hosts, including the process of aging. In this interview, he discusses the questions shaping his research, how they evolved over the years, and his guiding principles for leading a lab.
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[
Worm Breeder's Gazette,
1992]
unc-4 LacZ expression in A-type motor neurons David M. Miller and Charles J. Niemeyer, Dept. of Cell Biology, Duke Univ. Medical Ctr, Durham, NC 27710
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[
Worm Breeder's Gazette,
1993]
DIFFERENTIAL EFFECTS OF DAUER-DEFECTIVE MUTATIONS ON L1- SPECIFIC SURFACE ANTIGEN SWITCHING. David G. Grenache and Samuel M. Politz, Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA.
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[
International Worm Meeting,
2019]
The Tokuyasu method is room-temperature immuno-electron microscopy of cryosections. This technique is based on using sucrose as a cryoprotectant during both freezing and thawing steps [Tokuyasu 1973]. This method is optimized for preserving the antigenicity of the sample. Thus, the cocktails of heavy metals, organic solvents, and plastics that are used to stabilize, infiltrate, and stain the fine ultrastructure in plastic-section microscopy are not used. As a result, the inherent nature of the sample is minimally altered. However, compared to plastic sections, preservation of fine ultrastructure in tokuyasu sections remains inadequate and inconsistent. Despite attempts to optimize by several groups, the morphology of neurons obtained with this method remains poor still. Here we show that this method could be modified to preserve the C. elegans ventral nerve cord (VNC) at an unprecedented level of structural detail while preserving antigenicity. Osmolality driven structural collapse is a significant drawback of using sucrose in the vitrification step. When a sample block is immersed in sucrose during the process of infusion, sucrose-driven collapse of cellular turgor pressure result in deformation of cellular structures that are prone to collapse. Such tissue is the ventral nerve cord (VNC) of C. elegans. When sucrose is used, neuronal profiles of the VNC collapse inwardly, and their plasma membranes appear jagged. The critical difference between our method and previously published ones [Tokuyasu 1973, Liou et al. 1996, Bos et al. 2004, Nicolle et al. 2015], is the lack of sucrose. Removing sucrose from the sample vitrification step prevented the sucrose driven collapse of cellular turgor pressure and thus preserved the cellular structural form. This modification also necessitated compensatory changes in sample embedding, orienting and freezing steps to maintain ease of cryosectioning and sample vitrification due to lack of sucrose. To address these challenges we used high-pressure freezing to cryo-immobilize C. elegans in an enhanced copper tube. This sample carrier enables robust loading, grouping, orienting, freezing, and downstream processing to generate ribbons of hydrated cryosections of gently fixed or unfixed worms. We plan to use the Tokuyasu method of thawing cryosections as a screening step before correlative cryo fluorescence microscopy and cryo-electron tomography of C. elegans ventral nerve cord.
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[
Worm Breeder's Gazette,
1994]
Strain names for non-C. elegans species Scott W. Emmonst, Armand Leroit, and David Fitch, Department of Molecular Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, Department of Biology, New York University, RmlOO9 Main Bldg., Washington Square, New York, NY 10003
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[
Worm Breeder's Gazette,
1994]
Cytology of degenerin-induced cell death in the PVM neuron David H. Hall, Guoqiang Gu+, Lei Gong#, Monica Driscoll#, and Martin Chalfie+, * Dept. Neuroscience, Albert Einstein College of Medicine, Bronx, N.Y. 10461 + Dept. Biological Sciences, Columbia University, New York, N.Y. 10027 # Dept. Molecular Biology and Biochemistry, Rutgers University, Piscataway, N.J. 08855
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[
J Vis Exp,
2017]
Next generation sequencing (NGS) technologies have revolutionized the nature of biological investigation. Of these, RNA Sequencing (RNA-Seq) has emerged as a powerful tool for gene-expression analysis and transcriptome mapping. However, handling RNA-Seq datasets requires sophisticated computational expertise and poses inherent challenges for biology researchers. This bottleneck has been mitigated by the open access Galaxy project that allows users without bioinformatics skills to analyze RNA-Seq data, and the Database for Annotation, Visualization, and Integrated Discovery (DAVID), a Gene Ontology (GO) term analysis suite that helps derive biological meaning from large data sets. However, for first-time users and bioinformatics' amateurs, self-learning and familiarization with these platforms can be time-consuming and daunting. We describe a straightforward workflow that will help C. elegans researchers to isolate worm RNA, conduct an RNA-Seq experiment and analyze the data using Galaxy and DAVID platforms. This protocol provides stepwise instructions for using the various Galaxy modules for accessing raw NGS data, quality-control checks, alignment, and differential gene expression analysis, guiding the user with parameters at every step to generate a gene list that can be screened for enrichment of gene classes or biological processes using DAVID. Overall, we anticipate that this article will provide information to C. elegans researchers undertaking RNA-Seq experiments for the first time as well as frequent users running a small number of samples.
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[
Science,
2002]
As any homeowner knows, timely maintenance is vital for keeping a building functioning properly after construction is finished. The same is evidently true for the complex architecture of the nervous system - at least in the roundworm. On page 686, neuroscientists Oliver Hobert, Oscar Aurelio, and David Hall describe a new family of proteins that help keep the wiring of the worm's nervous system tangle free.
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[
Parasitol Today,
1996]
Historically, peptidergic substances (in the form of neurosecretions) were linked to moulting in nematodes. More recently, there has been a renewal of interest in nematode neurobiology, initially triggered by studies demonstrating the localization of peptide immunoreactivities to the nervous system. Here, David Brownlee, Ian Fairweather, Lindy Holden-Dye and Robert Walker will review progress on the isolation of nematode neuropeptides and efforts to unravel their physiological actions and inactivation mechanisms. Future avenues for research are suggested and the potential exploitation of peptidergic pathways in future therapeutic strategies