JoVE General
Pharmacological and Functional Genetic Assays to Manipulate Regeneration of the Planarian Dugesia japonica
Department of Pharmacology and The Stem Cell Institute, University of Minnesota Medical School
An attractive model for studying stem cell differentiation within a live animal is the planarian flatworm. Regeneration is studied by simple amputation experiments that are easily performed in a basic laboratory and are amenable to pharmacological and genetic (in vivo RNAi) manipulation as detailed by protocols in this article.
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
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
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 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
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
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 Immunology and Infection
RNAi Screening for Host Factors Involved in Vaccinia Virus Infection using Drosophila Cells
Department of Microbiology, Penn Genome Frontiers Institute, University of Pennsylvania
Novel host factors involved in viral infection can be identified through cell-based genome-wide loss of function RNAi screening. A Drosophila cell culture model is particularly amenable to this approach due to the ease and efficiency of RNAi. Here we demonstrate this technique using vaccinia virus as an example.
JoVE General
Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
Institute of Pathology, Charité Campus Mitte
For development of RNA interference (RNAi)-based therapies, a novel strategy was developed, transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells. Here, tkRNAi was successfully applied for reversal of classical ABCB1-mediated multidrug resistance (MDR) of cancer cells.
JoVE Immunology and Infection
RNA Interference in Ticks
1Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, 2(CSIC-UCLM-JCCM), Instituto de Investigación en Recursos Cinegéticos IREC
A method for RNA interference (RNAi) by injection of dsRNA into unfed ticks is described. RNAi is the most widely used gene-silencing technique in ticks where the use of other methods of genetic manipulation has been limited.
JoVE General
MISSION esiRNA for RNAi Screening in Mammalian Cells
Max Planck Institute of Molecular Cell Biology and Genetics
Here we use a human esiRNA library in a high-throughput screen for genes involved in cell division. We demonstrate how to set up and conduct an esiRNA screens, as well as how to analyze and validate the results.
JoVE General
Preparation of Drosophila S2 cells for Light Microscopy
Department of Cell Biology and Anatomy, University of Arizona (UOA)
Drosophila Schneider (S2) cells are an increasingly popular system for the discovery and functional analysis of genes. Our goal is to describe some of the microscopic techniques that make S2 cells such an increasingly important experimental system.
JoVE General
RNAi-mediated Gene Knockdown and In Vivo Diuresis Assay in Adult Female Aedes aegypti Mosquitoes
1Biology Department, New Mexico State University, 2Molecular Biology Department, New Mexico State University
In this protocol we combine RNAi-mediated gene silencing with an in vivo diuresis assay to study the effects knockdown of genes of interest has on mosquito fluid excretion.
JoVE General
Primary Cell Cultures from Drosophila Gastrula Embryos
1Department of Genetics, Harvard Medical School, 2 , Howard Hughes Medical Institute
We provide a detailed protocol for preparing primary cells dissociated from Drosophila embryos. The ability to carry out the effective RNAi perturbation, together with other molecular, biochemical and cell imaging methods will allow a variety of questions to be addressed in Drosophila primary cells.
JoVE General
Protocol for RNAi Assays in Adult Mosquitoes (A. gambiae)
Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University
Reverse genetic approaches have proven extremely useful for determining which genes underly resistance to vector pathogens in mosquitoes. This video protocol illustrates a method used by the Dimopoulos lab to inject dsRNA into Anopheles gambiae mosquitoes, which harbor the malaria parasite. The technique manipulating the injection setup and injecting dsRNA into the thorax is illustrated.
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 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
Virus-induced Gene Silencing (VIGS) in Nicotiana benthamiana and Tomato
1Plant Pathology and Plant-Microbe Biology, Cornell University, 2Boyce Thompson Institute for Plant Research
Description of a virus-induced gene silencing (VIGS) method for knock-down of gene expression in Nicotiana benthamiana and tomato.
JoVE Clinical and Translational Medicine
DNA Vector-based RNA Interference to Study Gene Function in Cancer
1Department of Cancer Biology and Comprehensive Cancer Center, Wake Forest University School of Medicine, 2Department of Pathology and Comprehensive Cancer Center, Wake Forest University School of Medicine
RNA interference (RNAi) possesses many advantages over gene knockout and has been broadly used as a tool in gene functional studies. The invention of DNA vector-based RNAi technology has made long term and inducible gene knockdown possible, and also increased the feasibility of gene silencing in vivo.
JoVE General
MISSION LentiPlex Pooled shRNA Library Screening in Mammalian Cells
Here we use a human LentiPlex pooled library and traditional sequencing methods to identify gene targets promoting cell survival. We demonstrate how to set up and deconvolute a LentiPlex screen and validate the results.
JoVE General
Oct4GiP Reporter Assay to Study Genes that Regulate Mouse Embryonic Stem Cell Maintenance and Self-renewal
Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences
We describe a fluorescence reporter assay to quickly identify and characterize genes that regulate mouse embryonic stem cell maintenance and self-renewal.
JoVE Neuroscience
Targeting Olfactory Bulb Neurons Using Combined In Vivo Electroporation and Gal4-Based Enhancer Trap Zebrafish Lines
1Department of Biology, Pace University, 2Cellular and Molecular Medicine, University of California, San Diego, 3Division of Cell Biology and Cell Physiology, Zoological Institute, Braunschweig University of Technology
The temporal and spatial resolution of genetic manipulations determines the spectrum of biological phenomena that they can perturb. Here we use temporally and spatially discrete in vivo electroporation, combined with transgenic lines of zebrafish, to induce expression of a GFP transgene specifically in neurons of the developing olfactory bulb.
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 General
Lentivirus Production
Diabetes Center, University of California, San Francisco - UCSF
To make lentiviruses, DNA vectors are transfected into human 293 cells. After harvest and concentrating the supernatant, virus titer is determined by fluorescence expression with a flow cytometer.
JoVE Bioengineering
High efficiency, Site-specific Transfection of Adherent Cells with siRNA Using Microelectrode Arrays (MEA)
School of Biological and Health Systems Engineering, Arizona State University
The article details the protocol for site-specific transfection of scrambled sequence of siRNA in an adherent mammalian cell culture using a microelectrode array (MEA).
JoVE General
Identifying the Effects of BRCA1 Mutations on Homologous Recombination using Cells that Express Endogenous Wild-type BRCA1
1Department of Biomedical Informatics, The Ohio State University, 2Departments of Molecular Immunology and Clinical Oncology, Tohoku University
We provide a method for testing BRCA1 variants in a tissue culture based assay for homologous recombination repair of DNA damage by depleting endogenous BRCA1 protein from a cell using RNAi and replacing it with a BRCA1 point mutant that contains a coding change.
JoVE General
Gene Transfer into Older Chicken Embryos by ex ovo Electroporation
1Albrecht-Kossel-Institute for Neuroregeneration, School of Medicine University of Rostock, 2Institute of Anatomy I, School of Medicine University of Jena
A method of gene transfer into chicken embryos at later incubation stages (older than Hamburger and Hamilton stage (HH) 22) is described. This method overcomes disadvantages of in ovo electroporation applied to older chicken embryos and is a useful technique to study gene function and regulation at older developmental stages.
JoVE Clinical and Translational Medicine
High Content Screening in Neurodegenerative Diseases
1Department of Clinical Genetics, VU University Medical Center, 2Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam
We describe a methodology combining automated cell culturing with high-content imaging to visualize and quantify multiple cellular processes and structures, in a high-throughput manner. Such methods can aid in the further functional annotation of genomes as well as identify disease gene networks and potential drug targets.
JoVE General
Live Dissection of Drosophila Embryos: Streamlined Methods for Screening Mutant Collections by Antibody Staining
Division of Biology, California Institute of Technology
We describe a streamlined protocol for generating "fillet" preparations of Drosophila embryos of specific genotypes. This protocol allows efficient execution of a variety of genetic screens. It also allows excellent visualization of structures in the late embryo.
JoVE General
Isolation of Protoplasts from Tissues of 14-day-old Seedlings of Arabidopsis thaliana
Crop and Soil Sciences, Cornell University
This video shows a procedure for isolating intact protoplasts from tissues of 14-day-old seedlings of Arabidopsis. Given that the isolated protoplasts remain intact for at least 96h and are isolated from seedlings instead of one-month-old mature plants, this procedure expedites assays requiring intact protoplasts.
JoVE General
Laser Microdissection Applied to Gene Expression Profiling of Subset of Cells from the Drosophila Wing Disc
Dipartimento di Biologia Strutturale e Funzionale, University of Naples
Laser microdissection was applied to analyse gene expression profiling in specific compartments of Drosophila wing disc subjected to localised RNAi in vivo. RNA extracted from equivalent areas of silenced and unsilenced compartments was analysed by quantitative RT-PCR to determine comparative gene expression profiling within the context of native tissue microecology.
JoVE Neuroscience
In ovo Electroporation of miRNA-based Plasmids in the Developing Neural Tube and Assessment of Phenotypes by DiI Injection in Open-book Preparations
Institute of Molecular Life Sciences, University of Zurich
A method by which gene expression in the neural tube can be downregulated in a cell type-specific, traceable manner is described. We demonstrate how in ovo electroporation of microRNA-based plasmids that elicit spatiotemporally controlled RNA interference can be used to investigate commissural axon guidance in the developing neural tube.
JoVE General
Time-lapse Imaging of Mitosis After siRNA Transfection
1Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, 2Fluorescence Microscopy Core Facility, University of Utah
Here we describe a basic protocol to image and quantify the mitotic timing of live mammalian tissue culture cells after siRNA transfection.
JoVE Neuroscience
Laser Capture Microdissection of Drosophila Peripheral Neurons
1Department of Molecular and Microbiology, George Mason University, 2Krasnow Institute for Advanced Study, George Mason University
In this video-article we present a method for isolating single or multiple Drosophila da neurons from third instar larvae using the infrared capture (IR) class of Laser Capture Microdissection (LCM). RNA obtained from the isolated neurons can be readily used for downstream applications including qRT-PCR or microarray analyses.
JoVE Immunology and Infection
Alphavirus Transducing System: Tools for Visualizing Infection in Mosquito Vectors
Microbiology, Immunology, and Pathology, Colorado State University
Methods for using alphavirus transducing systems to express fluorescent reporters in vitro and in adult mosquitoes are described. This technique may be adapted to express any protein of interest in lieu of or in addition to a reporter.
JoVE Neuroscience
Methods for Study of Neuronal Morphogenesis: Ex vivo RNAi Electroporation in Embryonic Murine Cerebral Cortex
1Department of Molecular, Cellular Biology and Biochemistry, Brown University, 2Institute for Brain Science, Brown University, 3Department of Psychiatry and Human Behavior, Warren Alpert School of Medicine, Brown University
To conduct a rapid assessment of the function of genes in the development of cerebral cortex, we describe methods involving the ex vivo electroporation of plasmids co-expressing inhibitory RNA (RNAi) and GFP in murine embryonic cortex. This protocol is amenable to the study of various aspects of neurodevelopment such as neurogenesis, neuronal migration and neuronal morphogenesis including dendrite and axon outgrowth.
JoVE General
Small-scale Nuclear Extracts for Functional Assays of Gene-expression Machineries
Department of Cell Biology, Harvard Medical School
A protocol for preparation of robust, small-scale HeLa nuclear extracts is described. This protocol is valuable for assays that require use of small populations of cells, such as cells treated with drugs or RNAi. The method should be applicable to a wide variety of gene expression assays and other cell types, including patient cells.
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 Immunology and Infection
Development of Cell-type specific anti-HIV gp120 aptamers for siRNA delivery
1Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, 2Graduate School of Biological Sciences, Beckman Research Institute of City of Hope, 3Shared Resource-DNA/RNA Peptide, Beckman Research Institute of City of Hope
Several 2’-Fluoro RNA aptamers against HIV-1Ba-L gp120 with nanomole affinity are isolated from a RNA library by in vitro SELEX procedure. A new dual inhibitory function anti-gp120 aptamer-siRNA chimera is created and shows considerable promise for systemic anti-HIV therapy.
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
Adult and Embryonic Skeletal Muscle Microexplant Culture and Isolation of Skeletal Muscle Stem Cells
School of Biosciences, University of Birmingham
The micro-dissected explants technique is a robust and reliable method for isolating proliferative skeletal muscle cells from juvenile, adult or embryonic muscles as a source of skeletal muscle stem cells. Uniquely, these cells have been clonally derived to produce skeletal muscle stem cell lines used for in vivo transplantation.
JoVE General
Localized RNAi and Ectopic Gene Expression in the Medicinal Leech
1Division of Biological Sciences, University of California San Diego - UCSD, 2Department of Physics, University of California San Diego - UCSD
In this video, we show a procedure for an accurate biolistic delivery of reagents into live tissue with a novel miniature gene gun. We are knocking down the expression of the axon guidance molecule Netrin in leech embryos by delivering molecules of dsRNA into the ventral body wall and ganglia of single segments.
JoVE Editorial
August 2011: This Month in JoVE
Here are some highlights from the August 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE Neuroscience
In utero Electroporation followed by Primary Neuronal Culture for Studying Gene Function in Subset of Cortical Neurons
1Center for Neurologic Diseases, Brigham and Woman's Hospital and Harvard Medical School, 2Department of Physiology and Neurobiology, University of Connecticut
In utero electroporation is a valuable method for transfecting neuronal progenitor cells in vivo. Depending upon the placement of the electrodes and the developmental timepoint of electroporation, certain subsets of cortical cells can be targeted. Targeted cells can then be analyzed in vivo or in vitro for effects of genetic alteration.
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 General
Fluorescent Labeling of Drosophila Heart Structures
1Biology Department, San Diego State University, 2Development and Aging Program, NASCR Center, The Sanford Burnham Institute for Medical Research
Here we describe a basic protocol for fluorescent labeling of different elements of heart tubes from larva and adult Drosophila melanogaster. These specimens are well-suited for imaging via fluorescent or confocal microscopy. This technique permits detailed structural analysis of the features of the hearts from a powerful model organism.
JoVE General
Monitoring Dynamic Changes In Mitochondrial Calcium Levels During Apoptosis Using A Genetically Encoded Calcium Sensor
Department of Neuroscience and Cell Biology, University of Texas Medical Branch
This protocol describes a method for real-time measurement of mitochondrial calcium fluxes by fluorescent imaging. The method takes advantage of a circularly permutated YFP-based dual-excitation ratiometric calcium sensor (ratiometric pericam-mt) selectively expressed in mitochondria.
JoVE General
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
Department of Biological Sciences, The University of Memphis
Circadian clocks function within individual cells, i.e., they are cell-autonomous. Here, we describe methods for generating cell-autonomous clock models using non-invasive, luciferase-based real-time bioluminescence technology. Reporter cells provide tractable, functional model systems for studying circadian biology.
JoVE General
Efficient Polyethylene Glycol (PEG) Mediated Transformation of the Moss Physcomitrella patens
Department of Biology and Biotechnology, Worcester Polytechnic Institute- WPI
A simple and efficient method to transform Physcomitrella pantens protoplasts is described. This method is adapted from protocols for Physocmitrella protonemal protoplast and Arabidopsis mesophyll protoplast transformation1.
JoVE General
Isolation and Genetic Manipulation of Adult Cardiac Myocytes for Confocal Imaging
Institute for Molecular Cell Biology, Universty of Saarland
Adult cardiac myocytes are primary cells that can be isolated from animal hearts and cultured for several days. Within this culture period adenoviral gene transfer can be used to express genetically encoded biosensors (GEBs) or fluorescent fusion proteins. Both approaches allow cellular investigations by means of confocal microscopy.
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