Caenorhabditis elegans:
A species of nematode that is widely used in biological, biochemical, and genetic studies.
JoVE General
Visualization of Caenorhabditis elegans Cuticular Structures Using the Lipophilic Vital Dye DiI
We present a method to visualize cuticle in live C. elegans using the red fluorescent lipophilic dye DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate), which is commonly used in C. elegans to visualize environmentally exposed neurons. With this optimized protocol, alae and annular cuticular structures are stained by DiI and observed using compound microscopy.
JoVE General
Basic Caenorhabditis elegans Methods: Synchronization and Observation
1Department of Cancer and Human Molecular Genetics, Bellvitge Institute for Biomedical Research, 2C. elegans Core Facility, Bellvitge Institute for Biomedical Research
The easiness of maintaining and propagating the nematode C. elegans make it a nice model organism to work with. The possibility of synchronizing worms allows the work with a significant amount of subjects at the same developmental stage, what facilitates the study of one particular process in many animals.
JoVE General
RNAi Screening to Identify Postembryonic Phenotypes in C. elegans
Department of Molecular and Cellular Medicine, Texas A&M University System Health Science Center
We describe a sensitized method to identify postembryonic regulators of protein expression and localization in C. elegans using an RNAi-based genomic screen and an integrated transgene that expresses a functional, fluorescently tagged protein.
JoVE General
Measuring Caenorhabditis elegans Life Span on Solid Media
1Department of Pathology, University of Washington, 2Molecular and Cellular Biology Program, University of Washington
In this article we present a general protocol for measuring life span of nematodes maintained on solid media with UV-killed bacterial food.
JoVE General
Imaging C. elegans Embryos using an Epifluorescent Microscope and Open Source Software
Human Genetics, University of Michigan
The C. elegans embryo is a powerful system for studying cell biology and development. We present a protocol for live imaging of C. elegans embryos utilizing DIC optics or fluorescence using readily available epifluorescent microscopes and open-source software.
JoVE Neuroscience
C. elegans Positive Butanone Learning, Short-term, and Long-term Associative Memory Assays
1Department of Molecular Biology, Lewis-Sigler Institute for Integrative Genomics, Princeton University, 2Lewis-Sigler Institute for Integrative Genomics, Princeton University
Here we describe methods to test C. elegans associative learning and short- and long-term associative memory. These population assays employ the worms abilities to chemotax toward volatile odorants, and form positive associations upon pairing food with the chemoattractant butanone. Increasing the number of conditioning periods induces long-term memory.
JoVE Bioengineering
Microfluidic-based Electrotaxis for On-demand Quantitative Analysis of Caenorhabditis elegans' Locomotion
1Department of Biology, McMaster University, 2Department of Mechanical Engineering, McMaster University
A semi-automated micro-electro-fluidic method to induce on-demand locomotion in Caenorhabditis elegans is described. This method is based on the neurophysiologic phenomenon of worms responding to mild electric fields (“electrotaxis”) inside microfluidic channels. Microfluidic electrotaxis serves as a rapid, sensitive, low-cost, and scalable technique to screen for factors affecting neuronal health.
JoVE General
Solid Plate-based Dietary Restriction in Caenorhabditis elegans
1Department of Internal Medicine, Division of Geriatric Medicine, University of Michigan, 2Department of Molecular and Integrative Physiology, University of Michigan
Here we present a protocol for performing solid plate-based dietary restriction in C. elegans with killed bacteria.
JoVE Neuroscience
C. elegans Tracking and Behavioral Measurement
1Donnelly Centre, University of Toronto, 2Department of Physics and Astronomy, Vrije Universiteit, 3Okinawa Institute of Science and Technology, 4Department of Physics, University of Toronto
We have developed a video-rate tracking microscope system that can record and quantify C. elegans behavior at high resolution and high speeds. We have also developed computational methods to reduce the dimensionality of the worm images to a fundamental set of measurements that completely describe the shape of the worm.
JoVE General
Vampiric Isolation of Extracellular Fluid from Caenorhabditis elegans
Department of Molecular and Cellular Biology, Harvard University
The model organism C. elegans uses pseudocoelomic fluid as a passive circulatory system. Direct assay of this fluid has not been previously possible. Here we present a novel technique to directly assay the extracellular space, and use systemic silencing signals during an RNAi response as a proof of principle example.
JoVE General
Isolation and In vitro Activation of Caenorhabditis elegans Sperm
Waksman Institute of Microbiology, Rutgers University
A protocol for isolating and activating spermatids from male C. elegans is described here. Cutting the posterior end of male releases spermatids. The spermatids can be activated by addition of protease.
JoVE General
High-throughput Screening and Biosensing with Fluorescent C. elegans Strains
1Department of Biology, University of Florida, 2Mount Desert Island Biological Laboratory
A procedure for liquid-based culturing and dispensing of C. elegans strains expressing fluorescent reporter proteins is described that does not require expensive sorting equipment. This approach can be applied to numerous inducible C. elegans genes for drug discovery or biosensing of contaminants.
JoVE Neuroscience
Assaying β-amyloid Toxicity using a Transgenic C. elegans Model
1Institute for Behavioral Genetics, University of Colorado, 2Integrative Physiology, University of Colorado
The intensely studied nematode worm Caenorhabditis elegans can be transgenically engineered to express the human β-amyloid peptide (Aβ). Induced expression of Aβ in C. elegans muscle leads to a rapid, reproducible paralysis phenotype that can be used to monitor treatments that modulate Aβ toxicity.
JoVE General
Measuring Caenorhabditis elegans Life Span in 96 Well Microtiter Plates
1Department of Chemical Physiology, The Scripps Research Institute, 2Department of Molecular and Experimental Medicine, The Scripps Research Institute
In this protocol we present a method to measure Caenorhabditis elegans lifespan in 96 well microtiter plates.
JoVE General
Generation of Transgenic C. elegans by Biolistic Transformation
Department of Medicine, University of Pittsburgh
Transgenic worms are commonly used in C. elegans research. Described is a simple, yet effective, protocol to introduce transgenes into worms using biolistic bombardment with DNA-coated gold particles. The effort involved and results of bombardment compare favorably with microinjection for the generation of transgenic animals.
JoVE General
Use of Time Lapse Microscopy to Visualize Anoxia-induced Suspended Animation in C. elegans Embryos
Department of Biological Sciences, University of North Texas
Described here is an in vivo technique to image sub-cellular structures in animals exposed to anoxia using a gas flow through microincubation chamber in conjunction with a spinning disc confocal microscope. This method is straightforward and flexible enough to suit a variety of experimental parameters and model systems.
JoVE General
C. elegans Chemotaxis Assay
1Life Sciences, Queen's University, 2Department of Chemical Engineering, Queen's University, 3Department of Biology, Queen's University
A method of quantitatively evaluating the chemotactic response of Caenorhabditis elegans is described. A chemotactic index (CI) was employed as a way to precisely evaluate the response of worms to certain targets, and serve as a platform of comparison between strains and compounds of interest.
JoVE General
Biochemical and High Throughput Microscopic Assessment of Fat Mass in Caenorhabditis Elegans
1Center for Human Genetic Research and Department of Medicine, Massachusetts General Hospital and Harvard Medical School, 2Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology
We present robust biochemical and microscopic methods for studying Caenorhabditis elegans lipid stores. A rapid, simple, fixing-staining procedure for fluorescent lipid droplet imaging leverages the spectral properties of the lipophilic dye Nile red. We then present biochemical measurement of triglycerides and phospholipids using solid phase extraction and gas chromatography-mass spectrometry.
JoVE General
The Production of C. elegans Transgenes via Recombineering with the galK Selectable Marker
1Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, 2Department of Medicine, Division of Geriatric Medicine and Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh
The ability to produce transgenes for Caenorhabditis elegans using genomic DNA carried by fosmids is particularly attractive as all of the native regulatory elements are retained. Described is a simple and robust procedure for the production of transgenes via recombineering with the galK selectable marker.
JoVE General
Quantitative and Automated High-throughput Genome-wide RNAi Screens in C. elegans
Centre d’Immunologie de Marseille-Luminy, Université de la Méditerranée
We describe a protocol using C. elegans and RNAi feeding libraries that allows automated measurement of multiple parameters such as fluorescence, size and opacity of individual worms in a population. We give one example of a screen to identify genes involved in anti-fungal innate immunity in C. elegans.
JoVE Neuroscience
In vivo Laser Axotomy in C. elegans
A protocol to cut neurons in C. elegans with a MicroPoint pulsed laser is presented. We describe setting up the system, immobilizing worms, and severing labeled neurons. Advantages include a relatively low-cost system and the ability to sever neuronal processes or ablate cells in vivo.
JoVE Neuroscience
In vivo Neuronal Calcium Imaging in C. elegans
1Department of Physiology and Biophysics, Boston University School of Medicine, 2Boston University Photonics Center
With its small transparent body, well-documented neuroanatomy and a host of amenable genetic techniques and reagents, C. elegans makes an ideal model organism for in vivo neuronal imaging using relatively simple, low-cost techniques. Here we describe single neuron imaging within intact adult animals using genetically encoded fluorescent calcium indicators.
JoVE Neuroscience
A Molecular Readout of Long-term Olfactory Adaptation in C. elegans
1Department of Biological Sciences and Institute for Neuroscience, George Washington University, 2Fred Hutchinson Cancer Research Center, 3Department of Cell and Tissue Biology, University of California San Francisco
Here we describe a molecular readout of long-term olfactory adaptation in Caenorhabditis elegans. The Protein Kinase G, EGL-4, is necessary for stable adaptation responses in the primary sensory neuron pair called AWC. During prolonged odor exposure EGL-4 translocates from the cytosol to nucleus of the AWC.
JoVE Neuroscience
Automated Quantification of Synaptic Fluorescence in C. elegans
Department of Biological Sciences, University of Toledo
The abundance of neurotransmitter receptors clustered at synapses strongly influences synaptic strength. This method quantifies fluorescently-labeled neurotransmitter receptors in three dimensions with single-synapse resolution in C. elegans, allowing hundreds of synapses to be rapidly characterized within a single sample without distortions introduced by z-plane projection.
JoVE General
Using RNA-mediated Interference Feeding Strategy to Screen for Genes Involved in Body Size Regulation in the Nematode C. elegans
1Department of Science, Borough of Manhattan Community College, City Universtiy of New York (CUNY), 2Department of Biology, Queens College, The City University of New York (CUNY), 3Biochemistry Program, The Graduate Center, Queens College, The City University of New York (CUNY)
We demonstrate how to use the RNAi feeding technique to knock down target genes and score body size phenotype in C. elegans. This method could be used for a large scale screen to identify potential genetic components of interest, such as those involved in body size regulation by DBL-1/TGF-β signaling.
JoVE General
Stable Isotopic Profiling of Intermediary Metabolic Flux in Developing and Adult Stage Caenorhabditis elegans
1Department of Pediatrics, The Children's Hospital of Philadelphia, 2Department of Pediatrics, University of Pennsylvania
Stable isotopic profiling by gas chromatography mass spectrometric analysis of intermediary metabolic flux is described in the nematode, Caenorhabditis elegans. Methods are detailed for assessing isotopic enrichment in carbon dioxide, organic acids, and amino acids following isotope exposure either during development on agar plates or during adulthood in liquid culture.
JoVE General
Generation of Stable Transgenic C. elegans Using Microinjection
Department of Biological Sciences, University of Alabama
This video demonstrates the technique of microinjection into the gonad of C. elegans to create transgenic animals.
JoVE General
Creating Defined Gaseous Environments to Study the Effects of Hypoxia on C. elegans
1Department of Biochemistry, University of Washington, 2Molecular and Cellular Biology Program, University of Washington
This paper details how to use continuous-flow hypoxia chambers to generate atmospheres with defined concentrations of O2 to understand biological responses to decreased O2. This system is easy to setup and maintain, and flexible enough to suit a wide range of O2 concentrations and model systems
JoVE General
Paradigms for Pharmacological Characterization of C. elegans Synaptic Transmission Mutants
Department of Biological Sciences, University of Alabama
This video demonstrates how to employ two neural stimulants, aldicarb and pentylenetetrazole (PTZ), in complementary ways to study synaptic function in the nematode, C. elegans. This complementary approach may also be used to shed light on evolutionarily conserved mechanisms for modulating neuronal synchrony and has implications for epilepsy and seizures.
JoVE General
Application of a C. elegans Dopamine Neuron Degeneration Assay for the Validation of Potential Parkinson's Disease Genes
Department of Biological Sciences, University of Alabama
This video demonstrates how to use C. elegans to assess dopaminergic neuron neurodegeneration as a model for Parkinson's disease. Furthermore, genetic screens are used to identify factors that either enhance degeneration or are neuroprotective.
JoVE Bioengineering
Quantitative Locomotion Study of Freely Swimming Micro-organisms Using Laser Diffraction
1Physics & Astronomy Department, Vassar College, 2Biology Department, Vassar College
Microscopic organisms like the free-swimming nematode C. elegans, live and behave in a complex three-dimensional environment. We report on a novel approach that provides analysis of C. elegans using diffraction patterns. This approach consists of tracking the temporal periodicity of diffraction patterns generated by directing laser light through a cuvette.
JoVE Bioengineering
Simple Microfluidic Devices for in vivo Imaging of C. elegans, Drosophila and Zebrafish
1Neurobiology, NCBS-TIFR, 2Department of Biological Sciences, TIFR
A simple microfluidic device has been developed to perform anesthetic free in vivo imaging of C. elegans, intact Drosophila larvae and zebrafish larvae. The device utilizes a deformable PDMS membrane to immobilize these model organisms in order to perform time lapse imaging of numerous processes such as heart beat, cell division and sub-cellular neuronal transport. We demonstrate the use of this device and show examples of different types of data collected from different model systems.
JoVE Editorial
August 2011: This Month in JoVE
Here are some highlights from the August 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE Bioengineering
Constructing a Low-budget Laser Axotomy System to Study Axon Regeneration in C. elegans
Department of Biology, University of Utah
Laser axotomy followed by time-lapse imaging is a sensitive way to assay the effects of mutations in C. elegans on axon regeneration. A high quality, but inexpensive, laser ablation system can be easily added to most microscopes. Time lapse imaging over 15 hours requires careful immobilization of the worm.
JoVE General
Time-lapse Microscopy of Early Embryogenesis in Caenorhabditis elegans
1Department of Biological Sciences, University of Alabama in Huntsville, 2NIDDK-National Institutes of Health
This article describes a technique for the visualization of the early events of embryogenesis in the nematode Caenorhabditis elegans.
JoVE Editorial
January 2012: This Month in JoVE
Here are some highlights from the January 2012 Issue of Journal of Visualized Experiments (JoVE).
JoVE General
Determining Genetic Expression Profiles in C. elegans Using Microarray and Real-time PCR
Department of Biological Sciences, Southwestern Oklahoma State University
Microarray analysis was conducted to determine genetic expression profiles in C. elegans, and real-time PCR was used to validate and quantify microarray data.
JoVE Neuroscience
A Caenorhabditis elegans Model System for Amylopathy Study
We describe methods to study aspects of amylopathies in the worm C. elegans. We show how to construct worms expressing human Aβ42 in neurons and how to test their function in behavioral assays. We further show how to obtain primary neuronal cultures that can be used for pharmacological testing.
JoVE General
Channelrhodopsin2 Mediated Stimulation of Synaptic Potentials at Drosophila Neuromuscular Junctions
Department of Biology, Brandeis
This procedure uses a blue light-activated algal channel and cell-specific genetic expression tools to evoke synaptic potentials with light pulses at the neuromuscular junction (NMJ) in Drosophila larvae. This technique is an inexpensive and easy-to-use alternative to suction electrode stimulation for synaptic physiology studies in research and teaching laboratories.
JoVE General
RNAi Mediated Gene Knockdown and Transgenesis by Microinjection in the Necromenic Nematode Pristionchus pacificus
Biology Department, California State University
In model organisms, transgenesis can manipulate gene functions while RNAi can knockdown specific mRNA transcripts 1-2. This protocol aims to illustrate the techniques needed to introduce stably transmitted DNA and transient double stranded RNA into the necromenic nematode Pristionchus pacificus for studies in evolutionary, developmental, and behavioral biology.
JoVE Neuroscience
Studying Synaptic Vesicle Pools using Photoconversion of Styryl Dyes
STED Microscopy of Synaptic Function, European Neuroscience Institute Göttingen
FM dyes have been of invaluable help in the understanding of synaptic dynamics. FMs are normally followed under the fluorescent microscope during different stimulation conditions. However, photoconversion of FM dyes combined with electron microscopy allows the visualization of distinct synaptic vesicle pools, among other ultrastructure components, in synaptic boutons.
JoVE General
Osmotic Avoidance in Caenorhabditis elegans: Synaptic Function of Two Genes, Orthologues of Human NRXN1 and NLGN1, as Candidates for Autism
1Departamento de Genética, Facultad de Ciencias, Universidad de Córdoba, 2Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)
Neurexins and neuroligins are membrane-neuron adhesion proteins which perform essential roles in synaptic differentiation and transmission. Neuroligin deficient mutants of C. elegans are defective in detecting osmotic strength, but when they also contain a mutation in the gene coding neurexin, they recover the wild type phenotype.
JoVE Bioengineering
Lensless Fluorescent Microscopy on a Chip
Department of Electrical Engineering, University of California, Los Angeles
A lensless on-chip fluorescent microscopy platform is demonstrated that can image fluorescent objects over an ultra-wide field-of-view of e.g., >0.6-8 cm2 with <4μm resolution using a compressive sampling based decoding algorithm. Such a compact and wide-field fluorescent on-chip imaging modality could be valuable for high-throughput cytometry, rare-cell research and microarray-analysis.
JoVE General
RNAi Interference by dsRNA Injection into Drosophila Embryos
Department of Biological Sciences, Oakland University
RNA interference has been proven very effective to analyze gene function in Drosophila tracheal development. A detailed protocol used by Jiang lab to inject dsRNA into fly embryos to knockdown gene expression is illustrated. This technique has the potential for screening genes required for tissue and organ development in Drosophila.
JoVE General
Identification of Protein Complexes in Escherichia coli using Sequential Peptide Affinity Purification in Combination with Tandem Mass Spectrometry
1Banting and Best Department of Medical Research, Donnelly Centre, University of Toronto, 2Deparment of Biochemistry, Research and Innovation Centre, University of Regina, 3Department of Medical Genetics and Microbiology, University of Toronto
Affinity purification of tagged proteins in combination with mass spectrometry (APMS) is a powerful method for the systematic mapping of protein interaction networks and for investigating the mechanistic basis of biological processes. Here, we describe an optimized sequential peptide affinity (SPA) APMS procedure developed for the bacterium Escherichia coli that can be used to isolate and characterize stable multi-protein complexes to near homogeneity even starting from low copy numbers per cell.
JoVE General
Dissecting and Recording from The C. Elegans Neuromuscular Junction
Department of Biological Sciences, University of Illinois, Chicago
Application of electrophysiology to accessible synapses provides a quantifiable measure of synaptic activity, useful in analyzing synaptic mutants. This article describes a dissection method used to expose the neuromuscular junctions (NMJ) of Caenorhabditis elegans (C. elegans) and briefly discusses some of the uses to which this preparation can be applied.
JoVE General
Aseptic Laboratory Techniques: Plating Methods
Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles
When working with media and reagents used to culture microorganisms, aseptic technique must be practiced to ensure contamination is minimized. A variety of plating methods are routinely used to isolate, propagate, or enumerate bacteria and phage, all of which incorporate procedures that maintain the sterility of experimental materials.
JoVE General
Detection of Protein Interactions in Plant using a Gateway Compatible Bimolecular Fluorescence Complementation (BiFC) System
1Department of Biology, University of Western Ontario, 2Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada
We have developed a technique to test protein-protein interactions in plant. A yellow fluorescent protein (YFP) is split into two non-overlapping fragments. Each fragment is cloned in-frame to a gene of interest via Gateway system, enabling expression of fusion proteins. Reconstitution of YFP signal only occurs when the inquest proteins interact.
JoVE General
Protein Membrane Overlay Assay: A Protocol to Test Interaction Between Soluble and Insoluble Proteins in vitro
Department of Biochemistry and Cell Biology, State University of New York
Testing protein-protein interaction is indispensable for dissection of protein functionality. Here, we introduce an in vitro protein-protein binding assay to probe a membrane-immobilized protein with a soluble protein. This assay provides a reliable method to test interaction between an insoluble protein and a protein in solution.
JoVE General
PAR-CliP - A Method to Identify Transcriptome-wide the Binding Sites of RNA Binding Proteins
1Howard Hughes Medical Institute, Laboratory of RNA Molecular Biology, Rockefeller University, 2Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, 3Biozentrum der Universität Basel and Swiss Institute of Bioinformatics (SIB), 4Biozentrum der Universität Basel and Swiss Institute of Bioinformatics (SIB), 5Genomics Resource Center, Rockefeller University
RNA transcripts are subject to extensive posttranscriptional regulation that is mediated by a multitude of trans-acting RNA-binding proteins (RBPs). Here we present a generalizable method to identify precisely and on a transcriptome-wide scale the RNA binding sites of RBPs.
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