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 Bioengineering
Developing Custom Chinese Hamster Ovary-host Cell Protein Assays using Acoustic Membrane Microparticle Technology
1Biomarker Division, BioScale, Inc., 2Bioprocessing Division, BioScale, Inc.
Development of custom assays on the ViBE platform for more sensitive, reproducible, automated results in complex matrices is described. The universal cartridge allows assays to be easily adapted for use with custom assays. This versatility enables rapid development and validation of novel assays or automated versions of existing manual assays, exemplified in this video.
JoVE General
Fast and Sensitive Colloidal Coomassie G-250 Staining for Proteins in Polyacrylamide Gels
Biological Medical Research Center (BMFZ), University Duesseldorf
This video shall popularize a colloidal Coomassie G-250 staining protocol according to Kang et al. for the detection of average 4 ng protein in gels. The staining is completed within 2 hours and without any effort. We routinely use Kang's protocol for analytical purposes in gel-based proteomics.
JoVE General
Knowing What Counts: Unbiased Stereology in the Non-human Primate Brain
1Department of Physiology, University of Montreal, 2Ecole d’optometrie, University of Montreal, 3Stereology Resource Center
The anatomical organization of the primate brain can provide important insights into normal and pathological conditions in humans. Unbiased stereology is a method for accurately and efficiently estimating the total neuron number (or other cell type) in a given reference space1.
JoVE Application Notes
The 22 Minute Western Blot - ADVERTISEMENT
JoVE Clinical and Translational Medicine
Production and Detection of Reactive Oxygen Species (ROS) in Cancers
Center for Cell and Gene Therapy, Baylor College of Medicine
Here we propose simple methods to test and evaluate the presence of reactive oxygen species in cells.
JoVE General
Fluorescent Labeling of COS-7 Expressing SNAP-tag Fusion Proteins for Live Cell Imaging
Division of Chemical Biology, New England Biolabs
SNAP-tag and CLIP-tag protein labeling systems enable the specific, covalent attachment of molecules, including fluorescent dyes, to a protein of interest in live cells. Once cloned and expressed, the tagged protein can be used with a variety of substrates for numerous downstream applications without having to clone again.
JoVE General
Separation of Mouse Embryonic Facial Ectoderm and Mesenchyme
1Department of Craniofacial Biology, University of Colorado Denver Anschutz Medical Campus, 2Department of Cell and Developmental Biology, University of Colorado Denver Anschutz Medical Campus
A protocol for separation of embryo facial ectoderm and mesenchyme is described. We use Dispase II to treat whole embryos first, dissect whole facial prominences out, and then separate the facial ectoderm and mesenchyme.
JoVE General
Rapid Homogeneous Detection of Biological Assays Using Magnetic Modulation Biosensing System
1Department of Physical Electronics, Faculty of Engineering, Tel Aviv University, 2Department of Biomedical Engineering, Washington University in St. Louis, 3Department of Biological Sciences, University of Illinois, 4Department of Cell Research and Immunology, Tel Aviv University
Magnetic modulation biosensing system is utilized to rapidly, sensitively and simply detect biological assays, such as DNA molecules and proteins.
JoVE Clinical and Translational Medicine
The Use of Reverse Phase Protein Arrays (RPPA) to Explore Protein Expression Variation within Individual Renal Cell Cancers
1Edinburgh Urological Cancer Group, University of Edinburgh, 2School of Medicine, University of St Andrews, 3Division of Pathology, University of Edinburgh, 4MRC Human Genetics Unit, MRC IGMM, University of Edinburgh, 5Department of Pathology, Western General Hospital, 6Breakthrough Breast Cancer Research Unit, University of Edinburgh, 7St Bartholomew's Cancer Institute, Experimental Cancer Medicine Centre, Queen Mary University of London
RPPA enables the protein expression of hundreds of samples, printed on nitrocellulose slides to be interrogated simultaneously, using fluorescently labelled antibodies. This technique has been applied to study the effect of drug treatment heterogeneity within clear cell renal carcinoma.
JoVE General
Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds
Institute of Plant Biology and Zürich-Basel Plant Science Center, University of Zürich
We report an efficient and simple method to isolate embryos at early stages of development from Arabidopsis thaliana seeds. Up to 40 embryos can be isolated in 1 hr to 4 hr, depending on the downstream application. The procedure is suitable for transcriptome, DNA methylation, reporter gene expression, immunostaining and fluorescence in situ hybridization analyses.
JoVE General
Staining of Proteins in Gels with Coomassie G-250 without Organic Solvent and Acetic Acid
Protein Expression and Purification Core Facility, EMBL Heidelberg
A short protocol for protein staining with Coomassie Brilliant Blue (CBB) G-250 in polyacrylamide gels is described without using organic solvents or acetic acid as in the classical staining procedures with CBB.
JoVE General
Staining Proteins in Gels
1Keck Graduate Institute of Applied Life Sciences, UVP, LLC, 2Proteomic Center, Keck Graduate Institute of Applied Life Sciences
Following separation by electrophoretic methods, proteins in a gel can be detected by several staining methods. Staining of proteins with Coomassie Blue, Silver Staining, SYPRO Orange, SYPRO Ruby are demonstrated in this video.
JoVE Applied Physics
Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing
Department of Physics, University of Alberta
Fluorescent-core microcavity sensors employ a high-index quantum-dot coating in the channel of silica microcapillaries. Changes in the refractive index of fluids pumped into the capillary channel cause shifts in the microcavity fluorescence spectrum that can be used to analyze the channel medium.
JoVE General
Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
1Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, 2Department of Anesthesiology, David Geffen School of Medicine, University of California, Los Angeles, 3Department of Anesthesiology, Medicine and Physiology, David Geffen School of Medicine, University of California, Los Angeles
We describe a simple protocol to identify brain proteins that bind to the full length C terminus of ATP-gated P2X2 receptors. The extension and systematic application of this approach to all P2X receptors is expected to lead to a better understanding of P2X receptor signaling.
JoVE Immunology and Infection
High-throughput Detection Method for Influenza Virus
1Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, 2Department of Microbiology, Mount Sinai School of Medicine, 3Laboratory of Molecular Genetics, Blood Research Institute, 4City of Milwaukee Health Department Laboratory, 5Division of Hematology-Oncology/BMT, Children's Hospital of Wisconsin, Medical College of Wisconsin, 6Division of Hematology and Oncology, Dept Medicine, Medical College of Wisconsin
This method describes the use of Infrared dye based imaging system for detection of H1N1 in bronchioalveolar lavage (BAL) fluid of infected mice at a high sensitivity. This methodology can be performed in a 96- or 384-well plate, requires <10 μl volume of test material and has the potential for concurrent screening of multiple pathogens.
JoVE Immunology and Infection
Visualisation and Quantification of Intracellular Interactions of Neisseria meningitidis and Human α-actinin by Confocal Imaging
Department of Cellular and Molecular Medicine, University of Bristol, UK
Neisseria meningitidis (Nm), a gram negative human-specific respiratory pathogen, can bind to human α-actinin. Here we present a protocol for visualisation of colocalisation of the bacterium with intracellular α-actinin after bacterial entry into human brain microvascular endothelial cells (HBMECs).
JoVE General
Chemically-blocked Antibody Microarray for Multiplexed High-throughput Profiling of Specific Protein Glycosylation in Complex Samples
1Institute for Hepatitis and Virus Research, 2Department of Microbiology and Immunology, Thomas Jefferson University, 3Drexel University College of Medicine, 4Van Andel Research Institute, 5Institute for Hepatitis and Virus Research, Serome Biosciences Inc.
In this study, we describe an improved protocol for a multiplexed high-throughput antibody microarray with lectin detection method that can be used in glycosylation profiling of specific proteins. This protocol features new reliable reagents and significantly reduces the time, cost, and lab equipment requirements as compared to the previous procedure.
JoVE Neuroscience
Strategies for Study of Neuroprotection from Cold-preconditioning
Department of Neurology, The University of Chicago Medical Center
We seek to define the neural immune signaling responsible for cold-preconditioning as means to identify novel targets for therapeutics development to protect brain before injury onset. We present strategies for such work that require biological systems, experimental manipulations plus technical capacities that are highly reproducible and sensitive.
JoVE General
Genome-wide Screen for miRNA Targets Using the MISSION Target ID Library
The Target ID Library is a plasmid-based, genome-wide collection of cloned cDNA used to identify miRNA targets. Here we demonstrate its use and application.
JoVE General
Batch Immunostaining for Large-Scale Protein Detection in the Whole Monkey Brain
1Cognitive Neuroscience Unit, Montreal Neurological Institute, 2Ècole d’Optomètrie, Universitè de Montrèal, 3Department of Psychology, McGill University
Large-scale immunodetection of target proteins across the entire primate brain is possible by employing novel tissue embedding and sectioning methods combined with the use of creative apparatus for batch staining of multiple free-floating sections at a given time.
JoVE General
Conversion of a Capture ELISA to a Luminex xMAP Assay using a Multiplex Antibody Screening Method
1Chemistry Research and Development, Luminex Corporation, 2Global Marketing, Luminex Corporation
An ELISA can be easily converted to a Luminex xMAP assay and, through the benefits of multiplexing, several antibodies can be screened simultaneously to identify an optimum antibody pair, resulting in increased sensitivity and dynamic range, while reducing assay cost.
JoVE General
Tangential Flow Ultrafiltration: A “Green” Method for the Size Selection and Concentration of Colloidal Silver Nanoparticles
1Department of Chemistry, Wright State University, 2Department of Neuroscience, Cell Biology, and Physiology, Wright State University
Tangential flow ultrafiltration (TFU) is a recirculation method used for the weight-based separation of biosamples. TFU was adapted to size-select (1-20 nm diameter) and highly concentrate a large volume of polydisperse silver nanoparticles (4 L of 15.2 μg ml-1 down to 4 ml of 8,539.9 μg ml-1) with minimal aggregation.
JoVE General
Direct Imaging of ER Calcium with Targeted-Esterase Induced Dye Loading (TED)
1Institute for Clinical Neurobiology, University of Wuerzburg, 2Department of Synapses - Circuits - Plasticity, Max Planck Institute of Neurobiology, Martinsried, 3Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians University of Munich
Targeted-esterase induced dye loading (TED) supports the analysis of intracellular calcium store dynamics by fluorescence imaging. The method bases on targeting of a recombinant Carboxylesterase to the endoplasmic reticulum (ER), where it improves the local unmasking of synthetic low-affinity Ca2+ indicator dyes in the ER lumen.
JoVE General
Immunoblot Analysis
1UVP, LLC, 2Proteomic Center, Keck Graduate Institute of Applied Life Sciences
Immunoblotting (western blotting) is a rapid and sensitive assay for the detection and characterization of proteins that works by exploiting the specificity inherent in antigen-antibody recognition. This video provides protocols for protein separation, blotting proteins onto membranes, immunoprobing, and visualization using chromogenic or chemiluminescent substrates.
JoVE Bioengineering
Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries
Department of Chemical and Biological Engineering, Iowa State University
This method describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries.
JoVE Clinical and Translational Medicine
High Throughput Sequential ELISA for Validation of Biomarkers of Acute Graft-Versus-Host Disease
Pediatric Blood and Marrow Transplant Program, University of Michigan
High throughput validation of multiple candidate biomarkers can be performed by sequential ELISA in order to minimize freeze/thaw cycles and use of precious plasma samples. Here, we demonstrate how to sequentially perform ELISAs for six different validated plasma biomarkers1-3 of graft-versus-host disease (GVHD)4 on the same plasma sample.
JoVE Neuroscience
Detection of Protein Palmitoylation in Cultured Hippocampal Neurons by Immunoprecipitation and Acyl-Biotin Exchange (ABE)
The reversible addition of palmitate to proteins is an important regulator of intracellular protein trafficking. This is of particular interest in neurons where many synaptic proteins are palmitoylated. We utilize a simple biochemical method to detect palmitoylated proteins in cultured neurons, which can be adapted for multiple cell types and tissues.
JoVE Clinical and Translational Medicine
A Strategy to Identify de Novo Mutations in Common Disorders such as Autism and Schizophrenia
1Centre of Excellence in Neuromics, CHUM Research Center and the Department of Medicine, Universite de Montreal, 2Center of Excellence in Neuromics, CHU Sainte Justine and CHUM Notre-Dame Research Centers, Universite de Montreal, 3Department of Medicine, Universite de Montreal
Molecular genetic strategy for finding de novo mutations causing common disorders such as autism and schizophrenia.
JoVE Immunology and Infection
ampliPHOX Colorimetric Detection on a DNA Microarray for Influenza
InDevR, Inc.
ampliPHOX colorimetric detection technology is presented as an inexpensive alternative to fluorescence detection for microarrays. Based on photopolymerization, ampliPHOX produces solid polymer spots visible to the naked eye in just a few minutes. Results are then imaged and automatically interpreted with a simple yet powerful software package.
JoVE Clinical and Translational Medicine
Analytical Techniques for Assaying Nitric Oxide Bioactivity
1Texas Therapeutics Institute, University of Texas Health Science Center at Houston, 2Deptartment of Pediatrics, Baylor College of Medicine
The endogenous production of nitric oxide (NO) regulates a wide variety of biological functions. It is becoming increasingly clear that disruption or dysregulation of NO based signaling is involved in many human diseases. Methods to quantify relevant NO metabolites may provide novel diagnostic or prognostic biomarkers for human disease.
JoVE Bioengineering
Fabrication of Electrochemical-DNA Biosensors for the Reagentless Detection of Nucleic Acids, Proteins and Small Molecules
1Department of Chemistry and Biochemistry, University Of California Santa Barbara, 2Department of Chemistry and Biochemistry, Program in BioMolecular Science and Engineering, University Of California Santa Barbara
"E-DNA" sensors, reagentless, electrochemical biosensors that perform well even when challenged directly in blood and other complex matrices, have been adapted to the detection of a wide range of nucleic acid, protein and small molecule analytes. Here we present a general procedure for the fabrication and use of such sensors.
JoVE General
Whole Mount RNA Fluorescent in situ Hybridization of Drosophila Embryos
1Institut de Recherches Cliniques de Montréal (IRCM), 2Department of Biochemistry, Université de Montréal
Here we describe a whole-mount fluorescent in situ hybridization (FISH) protocol for determining the expression and localization properties of RNAs expressed during embryogenesis in the fruit fly, Drosophila melanogaster.
JoVE General
In-vivo Detection of Protein-protein Interactions on Micro-patterned Surfaces
Institute of Biophysics, Johannes Kepler Universitat Linz
This video shows experiments with subsequent analysis of protein-protein interactions by the use of micro-patterned surfaces. The approach offers the possibility to detect protein interactions in living cells and combines high throughput capabilities with the possibility to extract quantitative information.
JoVE General
Paraffin-Embedded and Frozen Sections of Drosophila Adult Muscles
Gene Expression and Signaling Research Group, Max Planck Institute for Biophysical Chemistry
Identification of mechanisms underlying muscle damage is crucial. Here we present the histological technique for preparing paraffin-embedded and frozen sections of Drosophila thoracic muscles. This allows analysis of muscle morphology and localization of protein and other muscle cell components.
JoVE General
Western Blotting Using the Invitrogen NuPage Novex Bis Tris MiniGels
Department of Physiology and Biophysics, University of California, Irvine (UCI)
This technical article describes a standard western-blotting procedure using the commercially available NuPAGE electrophoresis Mini-Gel system from Invitrogen.
JoVE General
Synthesis of an In vivo MRI-detectable Apoptosis Probe
1Division of Cardiovascular Medicine, Department of Medicine, Stanford University Medical Center, 2Division of Cardiology, Department of Medicine, University of California, San Francisco, 3San Francisco VAMC
Early detection of apoptosis may identify at-risk cell populations in a variety of diseases. Here we demonstrate a method to link an early apoptosis-detection protein (Annexin V) to a MRI-detectable iron oxide nanoparticle (SPIO). This method may be extended to other proteins of interest to generate MRI-detectable molecular imaging probes.
JoVE Bioengineering
Bacterial Detection & Identification Using Electrochemical Sensors
1Research Service, Veterans Affairs Greater Los Angeles Healthcare System, 2Department of Urology, The David Geffen School of Medicine, University of California, Los Angeles, 3GeneFluidics, 4Division of Infectious Diseases, Veterans Affairs Greater Los Angeles Healthcare System, 5Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles
We describe an electrochemical sensor assay method for rapid bacterial detection and identification. The assay involves a sensor array functionalized with DNA oligonucleotide capture probes for ribosomal RNA (rRNA) species-specific sequences. Sandwich hybridization of target rRNA with the capture probe and a horseradish peroxidase-linked DNA oligonucleotide detector probe produces a measurable amperometric current.
JoVE Immunology and Infection
Quantitative Analyses of all Influenza Type A Viral Hemagglutinins and Neuraminidases using Universal Antibodies in Simple Slot Blot Assays
1Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health canada, 2National Institute for the Control of Pharmaceutical and Biological Products, The State Food and Drug Administration, Beijing, 3Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 4Microbiology Department, Faculty of Medicine, King Abdulaziz University, 5National Microbiology Laboratory, Public Health Agency of Canada
A simple slot blot method was developed for the quantification of influenza viral hemagglutinin and neuraminidase using universal antibodies targeting their most conserved sequences identified through bioinformatics analyses. This innovative approach may provide a useful alternative to quantitative determination of all viral hemagglutinin and neuraminidase.
JoVE Bioengineering
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
1Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, 2Clinical Research Laboratory, 81st Medical Group, Keesler Air Force Base
Lytic phage biosensors and antibody beads are able to discriminate between methicillin resistant (MRSA) and sensitive staphylococcus bacteria. The phages were immobilized by a Langmuir-Blodgett method onto a surface of a quartz crystal microbalance sensor and worked as broad range staphylococcus probes. Antibody beads recognize MRSA.
JoVE Bioengineering
Biomolecular Detection employing the Interferometric Reflectance Imaging Sensor (IRIS)
1Department of Electrical and Computer Engineering, Boston University, 2Department of Biomedical Engineering, Boston University, 3Center for Advanced Genomics Technology, Boston University, 4Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, 5Department of Microbiology, Boston University School of Medicine, 6CNR (National Research Council), Istituto di Chimica del Riconoscimento Molecolare
Quantitative, high-throughput, real-time, and label-free biomolecular detection (DNA, protein, etc.) on SiO2 surfaces can be achieved using a simple interferometric technique which relies on LED illumination, minimal optical components, and a camera. The Interferometric Reflectance Imaging Sensor (IRIS) is inexpensive, simple to use, and amenable to microarray formats.
JoVE Neuroscience
Detection of Neuritic Plaques in Alzheimer's Disease Mouse Model
Department of Neuroscience, The University of British Columbia
One of the pathological characteristics of AD is the formation of Amyloid β protein positive neuritic plaques. In this protocol we describe two methods to detect neuritic plaques in transgenic AD model mice: immunohistochemical detection using the ABC and DAB method and fluorescent detection using thioflavin S staining method.
JoVE Neuroscience
Comprehensive Profiling of Dopamine Regulation in Substantia Nigra and Ventral Tegmental Area
Dopamine is distinctly regulated in the midbrain nuclei, which contain the cell bodies and dendrites of the dopamine neurons. Here we describe a dissection and sample-handling approach to maximize results, and thus conclusions and insights, on dopamine regulation in the midbrain nuclei of the substantia nigra (SN) and ventral tegmental area (VTA) in rodents.
JoVE Application Notes
Abcam Quantitative Cleaved PARP-1 High-Throughput In-Cell ELISA (ICE) Assay - ADVERTISEMENT
Abcam, plc
Quantitative measurement of cleaved PARP-1 in fixed adherent or suspension cells by high-throughput In-Cell ELISA for using infra-red Li-Cor imaging system.
JoVE Immunology and Infection
Detection of Bacteria Using Fluorogenic DNAzymes
1Department of Biochemistry and Biomedical Sciences, McMaster University, 2Department of Chemistry and Chemical Biology, McMaster University
We have recently reported a novel approach for generating fluorogenic DNAzyme probes that can be applied to set up a simple, "mix-and-read" fluorescent assay for bacterial detection. These special DNA probes catalyze the cleavage of a chromophore-modified DNA-RNA chimeric substrate in the presence of crude extracellular mixture (CEM) produced by a specific bacterium, thereby translating bacterial detection into fluorescence signal generation. In this report we will describe key experimental procedures where a specific DNAzyme probe denoted "RFD-EC1" is employed for the detection of the model bacterium, Escherichia coli (E. coli).
JoVE General
Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
1Department of Medicine, Albert Einstein College of Medicine, 2Diabetes Research and Training Center, Albert Einstein College of Medicine, 3Department of Genetics, Albert Einstein College of Medicine
An accurate, short, sophisticated and cheap method is described that assesses telomere length in multiple tissues and species using qRT-PCR. In addition, we will describe a simple assay to assess telomerase activity as a complementary backbone test for telomere length.
JoVE General
Detection of Protein Ubiquitination
Signal Transduction Program, The Sanford Burnham Institute for Medical Research
Ubiquitination is a key posttranslational modification carried out by a set of three enzymes. Mutations of genes involved in this modification are associated with many different human diseases. Here, we describe protocols to detect protein ubiquitination in cultured cells in vivo and test tubes in vitro.
JoVE General
IP-FCM: Immunoprecipitation Detected by Flow Cytometry
Department of Immunology, College of Medicine, Mayo Clinic
The IP-FCM method is presented, which allows a sensitive, robust, biochemical assessment of native protein-protein interactions, without requiring genetic engineering or large sample sizes.
JoVE General
Mutagenesis and Analysis of Genetic Mutations in the GC-rich KISS1 Receptor Sequence Identified in Humans with Reproductive Disorders
1Division of Endocrinology and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, 2Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine
Mutations in the kisspeptin receptor (KISS1R) are associated with reproductive disorders in patients. Here we describe how to introduce mutations of interest in the GC-rich sequence of KISS1R as well as the use of KISS1R constructs to characterize the degradation pathway of the receptor by immunoprecipitation and western blot.
JoVE Immunology and Infection
Two Methods of Heterokaryon Formation to Discover HCV Restriction Factors
1Division of Experimental Virology, Twincore, Centre for Experimental and Clinical Infection Research, 2Aaron Diamond AIDS Research Center, Laboratory of Retrovirology, The Rockefeller University, NY
We describe two methods for conditional trans-complementation of hepatitis C virus (HCV) assembly and the completion of the full viral life cycle, which rely on heterokaryon formation. These techniques are suitable to screen for cell lines that express dominant restriction factors, which preclude production of infectious HCV progeny.
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