Genomic Instability:
An increased tendency of the Genome to acquire Mutations when various processes involved in maintaining and replicating the genome are dysfunctional.
JoVE General
Studying Age-dependent Genomic Instability using the S. cerevisiae Chronological Lifespan Model
Here we describe a set of DNA mutation assays that can be combined with the yeast chronological life span model to study the genes/pathways that regulate or contribute to genomic DNA instability during aging.
JoVE General
Quantitation and Analysis of the Formation of HO-Endonuclease Stimulated Chromosomal Translocations by Single-Strand Annealing in Saccharomyces cerevisiae
1Irell & Manella Graduate School of Biological Sciences, 2Department of Molecular and Cellular Biology, City of Hope Comprehensive Cancer Center and Beckman Research Institute, 3Department of Biochemistry and Molecular Biology, University of Southern California, Norris Comprehensive Cancer Center
The HO-stimulated translocation assay monitors single-strand annealing following the creation of DNA double-strand breaks at multiple loci in diploid Saccharomyces cerevisiae. This mechanism may model genome rearrangements in somatic cells of higher eukaryotes following exposure to high doses of ionizing radiation.
JoVE General
Visualization of DNA Replication in the Vertebrate Model System DT40 using the DNA Fiber Technique
1Department of Molecular Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, 2Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw
DT40, a model vertebrate genetic system, provides a powerful tool to analyze protein function. Here we describe a simple method that allows qualitative analysis of parameters that influence DNA synthesis during the S-phase in DT40 cells at the single molecule level.
JoVE General
Deficient Pms2, ERCC1, Ku86, CcOI in Field Defects During Progression to Colon Cancer
1Department of Cell Biology and Anatomy, College of Medicine, University of Arizona, Tucson, 2Southern Arizona Veterans Affairs Health Care System, Tucson, AZ, 3Department of Surgery, College of Medicine, University of Arizona, Tucson, 4Biomedical Diagnostics and Research, Tucson, AZ, 5Department of Medicine, College of Medicine, University of Arizona, Tucson
Reduced/absent expression of Pms2 and/or ERCC1 in entire crypts is a frequent event within 10 cm on each side of colonic adenocarcinomas, likely the basis of a field defect with high mutability and progression to cancer. Deficiency in Ku86 or CcOI is much less frequent in these field defects.
JoVE General
Studying Mitotic Checkpoint by Illustrating Dynamic Kinetochore Protein Behavior and Chromosome Motion in Living Drosophila Syncytial Embryos
Institute for Cell and Molecular Biosciences, University of Newcastle, United Kingdom
The kinetochore is where the SAC initiates its signal monitoring the mitotic segregation of the sister chromatids. A method is described to visualize the recruitment and turnover of one of the kinetochore proteins and its coordination with the chromosome motion in Drosophila embryos using a Leica laser scanning confocal system.
JoVE General
Chromosome Replicating Timing Combined with Fluorescent In situ Hybridization
A quantitative method for the analysis of chromosome replication timing is described. The method utilizes BrdU incorporation in combination with fluorescent in situ hybridization (FISH) to assess replication timing of mammalian chromosomes. This technique allows for the direct comparison of rearranged and un-rearranged chromosomes within the same cell.
JoVE General
Two- and Three-Dimensional Live Cell Imaging of DNA Damage Response Proteins
1Department of Radiation Oncology, Virginia Commonwealth University, 2Department of Biochemistry & Molecular Biology, Virginia Commonwealth University, 3Department of Anatomy & Neurobiology, Virginia Commonwealth University, 4Massey Cancer Center, Virginia Commonwealth University
This protocol describes a method for visualizing a DNA double-strand break signaling protein activated in response to DNA damage as well as its localization during mitosis.
JoVE General
Study of the DNA Damage Checkpoint using Xenopus Egg Extracts
Department of Biology, University of North Carolina at Charlotte
Xenopus egg extract is a useful model system to investigate the DNA damage checkpoint. This protocol is for the preparation of Xenopus egg extracts and DNA damage checkpoint inducing reagents. These techniques are adaptable to a variety of DNA damaging approaches in the study of the DNA damage checkpoint signaling.
JoVE Clinical and Translational Medicine
Patient Derived Cell Culture and Isolation of CD133+ Putative Cancer Stem Cells from Melanoma
1Institute of Pathology, Laboratory of Molecular Tumor Pathology, Charité - Universitätsmedizin Berlin, 2Institute for Chemistry and Biochemistry, Free University Berlin, 3Laboratory for Functional Genomics Charité (LFGC), Charité - Universitätsmedizin Berlin, 4Comprehensive Cancer Center Charité, Charité - Universitätsmedizin Berlin
This article describes the preparation of freshly obtained melanoma tissue into primary cell cultures, and how to remove contaminations of erythrocytes and fibroblasts from the tumor cells. Finally, we describe how CD133+ putative melanoma stem cells are sorted from the CD133- bulk using Magnetic Activated Cell Sorting (MACS).
JoVE General
Genetic Studies of Human DNA Repair Proteins Using Yeast as a Model System
Laboratory of Molecular Gerontology, National Institute on Aging, NIH
Genetic studies in yeast can be employed to investigate the molecular and cellular functions of human genes in cellular DNA metabolism. Methods are described for the genetic characterization of the human WRN gene product defective in the premature aging disorder Werner syndrome in functionally conserved pathways using yeast as a tractable model system.
JoVE General
Environmentally Induced Heritable Changes in Flax
Department of Biology, Case Western Reserve University
Growing some flax varieties under nutrient stress results in genomic variation within a subset of the genome and phenotypic variation. A complex insertion at a specific site is associated with growth under various nutrient regimes and with changes in gene expression around this site.
JoVE General
Combined Immunofluorescence and DNA FISH on 3D-preserved Interphase Nuclei to Study Changes in 3D Nuclear Organization
1Department of Pathology, New York University School of Medicine, 2New York University Center for Health Informatics and Bioinformatics, 3NYU Cancer Institute, 4Department of Pathology and Yale Cancer Center, Yale University School of Medicine
Here we describe a protocol for simultaneous detection of histone modifications by immunofluorescence and DNA sequences by DNA FISH followed by 3D microscopy and analyses (3D immuno-DNA FISH).
JoVE General
The Logic, Experimental Steps, and Potential of Heterologous Natural Product Biosynthesis Featuring the Complex Antibiotic Erythromycin A Produced Through E. coli
1Chemical and Biological Engineering Department, State University of New York at Buffalo, 2Chemical Engineering Department, Massachusetts Institute of Technology
The heterologous biosynthesis of erythromycin A through E. coli includes the following experimental steps: 1) genetic transfer; 2) heterologous reconstitution; and 3) product analysis. Each step will be explained in the context of the motivation, potential, and challenges in producing therapeutic natural products using E. coli as a surrogate host.
JoVE General
A Practical and Novel Method to Extract Genomic DNA from Blood Collection Kits for Plasma Protein Preservation
1Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine and Children's Health Care of Atlanta, 2Division of Rheumatology, Department of Pediatrics, Emory University School of Medicine and Children's Health Care of Atlanta
We are describing a new method of isolating genomic DNA from whole blood collected for plasma/serology. After plasma collection, the compacted blood is usually discarded. Our novel method represents a significant improvement over existing methods and makes DNA and plasma available from a single collection, without requesting additional blood.
JoVE Clinical and Translational Medicine
Spectral Karyotyping to Study Chromosome Abnormalities in Humans and Mice with Polycystic Kidney Disease
1Department of Pharmacology, University of Toledo, College of Pharmacy and Pharmaceutical Sciences, 2Department of Emergency and Intensive Care, ProMedica Sponsored Research
Spectral Karyotyping (SKY) is an advanced cytogenetics technique to identify genomic and chromosomal aberrations. This technique takes advantage of chromosome painting probes, which allow classification of all chromosomes. SKY can also identify complex chromosome aberrations and segregation defects in mice and humans with various diseases, including polycystic kidney disease.
JoVE General
Polymerase Chain Reaction: Basic Protocol Plus Troubleshooting and Optimization Strategies
Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles
PCR has emerged as a common technique in many molecular biology laboratories. Provided here is a quick guide to several conventional PCR protocols. Because each reaction is a unique experiment, optimal conditions required to generate a product vary. Understanding the variables in a reaction will greatly enhance troubleshooting efficiency, thereby increasing the chance to obtain the desired result.
JoVE Applied Physics
Micro 3D Printing Using a Digital Projector and its Application in the Study of Soft Materials Mechanics
Department of Mechanical Engineering, Massachusetts Institute of Technology
We demonstrate controlled pattern transformation of swelling gel tubes by elastic instability. A simple projection micro stereo-lithography setup is built using an off-the-shelf digital data projector to fabricate three-dimensional polymeric structures in a layer-by-layer fashion. Swelling hydrogel tubes under mechanical constraint display various circumferential buckling modes depending on dimension.
JoVE Neuroscience
An Experimental Platform to Study the Closed-loop Performance of Brain-machine Interfaces
Department of Bioengineering, Imperial College London
We use a closed-loop fly-machine interface to investigate general principles in neuronal control.
JoVE General
Global Gene Expression Analysis Using a Zebrafish Oligonucleotide Microarray Platform
School of Health Sciences, Purdue University
Gene microarrays are powerful tools in gene expression profiling at a genome-wide level. This technology has application in a variety of biological disciplines including developmental biology and toxicology. In this video, we detail a protocol for global gene expression analysis using a comprehensive oligonucleotide microarray platform for the zebrafish.
JoVE General
Optimized PCR-based Detection of Mycoplasma
Product Management, Sigma-Aldrich
The LookOut Mycoplasma PCR Detection Kit utilizes the polymerase chain reaction (PCR), which is established as the method of choice for highest sensitivity in the detection of Mycoplasma, Acholeplasma, and Ureaplasma contamination in cell cultures and other cell culture derived biologicals.
JoVE General
Purification of the M. magneticum Strain AMB-1 Magnetosome Associated Protein MamAΔ41
MamA is a unique Magnetosome associated protein which was shown to be involved in magnetosome activation. Here we present the purification protocol of MamA deletion mutant (MamAΔ41) from M. magneticum AMB-1.
JoVE General
Selective Capture of 5-hydroxymethylcytosine from Genomic DNA
1Department of Human Genetics, Emory University School of Medicine, 2Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago
Described is a two-step labeling process using β-glucosyltransferase (β-GT) to transfer an azide-glucose to 5-hmC, followed by click chemistry to transfer a biotin linker for easy and density-independent enrichment. This efficient and specific labeling method enables enrichment of 5-hmC with extremely low background and high-throughput epigenomic mapping via next-generation sequencing.
JoVE General
Genomic MRI - a Public Resource for Studying Sequence Patterns within Genomic DNA
Department of Medicine, University of Toledo Health Science Campus
We present a public computational web site for the analysis of genomic sequences. It detects DNA sequence patterns with various non-random nucleotide compositions. This resource also generates randomized sequences with diverse levels of complexity.
JoVE General
Large Insert Environmental Genomic Library Production
Department of Microbiology and Immunology, University of British Columbia - UBC
Construction of a fosmid library with environmental genomic DNA isolated from the vertical depth continuum of a seasonally hypoxic fjord is described. The resulting clone library is picked into 384-well plates and archived for downstream sequencing and functional screening by the application of an automated colony picking system.
JoVE General
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Wellcome Trust Centre for Human Genetics, University of Oxford
Genetic associations often remain unexplained at a functional level. This method aims to assess the effect of phenotype-associated genetic markers on gene expression by analyzing cells heterozygous for transcribed SNPs. The technology allows accurate measurement by MALDI-TOF mass spectrometry to quantify allele-specific primer extension products.
JoVE Neuroscience
Laser Capture Microdissection of Enriched Populations of Neurons or Single Neurons for Gene Expression Analysis After Traumatic Brain Injury
Department of Anesthesiology, University of Texas Medical Branch
We describe how to use laser capture microdissection (LCM) to obtain enriched populations of hippocampal neurons or single neurons from frozen sections of the injured rat brain for subsequent gene expression analysis using quantitative real time PCR and/or whole-genome microarrays.
JoVE General
Extraction of High Molecular Weight Genomic DNA from Soils and Sediments
Department of Microbiology and Immunology, University of British Columbia - UBC
A methodology to isolate high molecular weight and high quality genomic DNA from soil microbial community is described.
JoVE Immunology and Infection
TransFLP — A Method to Genetically Modify Vibrio cholerae Based on Natural Transformation and FLP-recombination
Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL)
A quick method to modify the genome of V. cholerae is described. These modifications include the deletion of single genes, gene clusters and genomic islands as well as the integration of short sequences (e.g. promoter elements or affinity-tag sequences). The method is based on the natural transformation and FLP-recombination.
JoVE General
Chromosomal Spread Preparation of Human Embryonic Stem Cells for Karyotyping
Institute of Biomedical Sciences, Federal University of Rio De Janeiro-UFRJ
Karyotyping is a simple and useful technique widely used for detecting genetic alterations. Here we describe a step by step protocol for chromosome spread preparation of human embryonic stem cells for monitoring the chromosomal status of these cells maintained in culture.
JoVE General
Genome Editing with CompoZr Custom Zinc Finger Nucleases (ZFNs)
Emerging Technologies, Sigma Life Science
The CompoZr Custom Zinc-Finger Nuclease (ZFN) Service enables precise genome editing in any organism or cell line at any locus defined by the user. This article describes the process for the design, manufacture, validation and implementation of the CompoZr Custom ZFN Service.
JoVE Clinical and Translational Medicine
Creating Rigidly Stabilized Fractures for Assessing Intramembranous Ossification, Distraction Osteogenesis, or Healing of Critical Sized Defects
Department of Orthopaedic Surgery, University of California, San Francisco
This article describes a method for stabilizing long bone fractures that is based on the application of modified Ilizarov external fixators 1-3. After application of the fixators and creation of the bone injury, healing can be assessed, distraction osteogenesis can be performed, or non-union or critical sized defect can be created and used to study therapeutic interventions.
JoVE General
Fluorescence-microscopy Screening and Next-generation Sequencing: Useful Tools for the Identification of Genes Involved in Organelle Integrity
DOE Plant Research Laboratory, Michigan State University
A fundamental quest in cell biology is to define the mechanisms that underlie the identity of the organelles that make eukaryotic cells. Here we propose a method to identify the genes responsible for the morphological and functional integrity of plant organelles using fluorescence microscopy and next-generation sequencing tools.
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
Generation of RNA/DNA Hybrids in Genomic DNA by Transformation using RNA-containing Oligonucleotides
School of Biology, Georgia Institute of Technology
This work shows how to form an RNA/DNA hybrid at the chromosomal level and reveal transfer of genetic information from RNA to genomic DNA in yeast cells.
JoVE General
Detection of Viral RNA by Fluorescence in situ Hybridization (FISH)
1Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, 2Department of Microbiology and Immunology, McGill University, 3Department of Medicine, Division of Experimental Medicine, McGill University
A fluorescence in situ hybridization (FISH) method was developed to visually detect viral genomic RNA using fluorescence microscopy. A probe is made with specificity to the viral RNA that can then be identified using a combination of hybridization and immunofluorescence techniques. This technique offers the advantage of identifying the localization of the viral RNA or DNA at steady-state, providing information on the control of intracellular virus trafficking events.
JoVE General
Concentration Determination of Nucleic Acids and Proteins Using the Micro-volume Bio-spec Nano Spectrophotometer
Shimadzu, Scientific Instruments
This communication presents data on the accuracy and reproducibility of the BioSpec-nano UV-VIS spectrophotometer for dsDNA and protein quantitation. Even with ultra-small volumes (1 to 2 L), reproducibility is excellent, while the automated wiping function improves throughput and results in minimal carryover for more precise results.
JoVE General
Genome-wide Gene Deletions in Streptococcus sanguinis by High Throughput PCR
The Philips Institute of Oral and Craniofacial Molecular Biology, Virginia Commonwealth University
An efficient genome-wide single gene mutation method has been established using Streptococcus sanguinis as a model organism. This method has achieved via high throughput recombinant PCRs and transformations.
JoVE General
Technical Demonstration of Whole Genome Array Comparative Genomic Hybridization
1Department of Cancer Genetics, BC Cancer Research Centre, 2Deeley Research Centre, BC Cancer Agency, 3Photography/Video Production, Multi-Media Services, BC Cancer Agency
This video is a technical demonstration of the hybridization protocol for whole genome tiling path array CGH, which scans the entire human genome using only 25-100 ng of DNA that can be isolated from a variety of sources, including archival formalin fixed material.
JoVE General
Primer-Free Aptamer Selection Using A Random DNA Library
1Department of Pathology, Hershey Medical Center, Pennsylvania State University, 2Department of Chemistry, Pennsylvania State University, 3Departments of Pathology, and Biochemistry and Molecular Biology, Hershey Medical Center, Pennsylvania State University, 4Materials Research Institute, Pennsylvania State University
SELEX protocols comprise multiple rounds of selection, each of which require regeneration of bound ligands, which in turn require fixed primer sequences flanking the random library regions. These fixed primer sequences can interfere with the selection process (false positives and negatives). Here we present a primer-free protocol.
JoVE General
DNA Extraction from Paraffin Embedded Material for Genetic and Epigenetic Analyses
1Department of Integrative Oncology, BC Cancer Research Centre, 2Interdisciplinary Oncology Program, University of British Columbia - UBC, 3Photography/Video Production, Multi-Media Services, BC Cancer Agency, 4Department of Pathology and Laboratory Medicine, University of British Columbia - UBC
This video demonstrates the protocol for DNA extraction from formalin-fixed paraffin-embedded material. This is a multi-day procedure in which tissue sections are deparaffinized with xylene, rehydrated with ethanol and treated with proteinase K to purify and isolate DNA for subsequent gene-specific or genome-wide analysis.
JoVE General
DNA Methylation: Bisulphite Modification and Analysis
1Epigenetics Group, Cancer Research Program, Garvan Institute of Medical Research, 2St Vincent's Clinical School, University of NSW
The gold standard for DNA methylation analysis is genomic sequencing of bisulphite converted DNA. This method takes advantage of the increased sensitivity of cytosine compared with 5-methylcytosine (5-MeC) to bisulphite deamination under acidic conditions. Unmethylated cytosines can be distinguished from methylated cytosines after PCR amplification of the target genomic DNA.
JoVE General
An Improved Method of RNA Isolation from Loblolly Pine (P. taeda L.) and Other Conifer Species
Warnell School of Forestry and Natural Resources, University of Georgia (UGA)
Many plant tissues, including phloem and xylem from loblolly pine (Pinus taeda L.), contain high levels of phenolics and polysaccharides that interfere with RNA purification. This presentation discusses techniques for the harvest of field-grown tissues and isolation of RNA of sufficient quality for microarrays and other genomic analyses.
JoVE General
Genome-wide Analysis using ChIP to Identify Isoform-specific Gene Targets
1Department of Biochemistry and Molecular Genetics, University of Illinois Chicago - UIC, 2Research Unit on Biomedical Informatics, Universitat Pompeu Fabra, 3Genome Technology Core, Whitehead Institute for Biomedical Research
Here we are presenting a chromatin immunoprecipitation (ChIP) procedure for genome-wide location analysis of protein isoforms that differ in a histone-binding domain. We are applying it to ChIP-Seq analysis to identify the targets of the KDM5A/JARID1A/RBP2 histone demethylase.
JoVE Neuroscience
High Sensitivity 5-hydroxymethylcytosine Detection in Balb/C Brain Tissue
Applications and Product Development, New England Biolabs
The EpiMark 5-hmC and 5-mC Analysis Kit can be used to analyze and quantitate 5-methylcytosine and 5-hydroxymethylcytosine within a spe cific locus. The kit distinguishes 5-mC from 5-hmC by the addition of glucose to the hydroxyl group of 5-hmC via an enzymatic reaction utilizing β-glucosyltransferase (T4-BGT). When 5-hmC occurs In the context of CCGG, this modification converts a cleavable MspI site to a non-cleavable site.
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 Bioengineering
Measurement of Bioelectric Current with a Vibrating Probe
Dermatology, University of California, Davis
The manufacture, calibration and use of non-invasive vibrating probes to measure bioelectric current in various biological systems is described.
JoVE Bioengineering
Fluorescence detection methods for microfluidic droplet platforms
1Department of Chemistry, Imperial College London, 2Department of Biochemistry, Protein Chip Research Center, Chungbuk National University, 3Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zurich
Droplet-based microfluidic platforms are promising candidates for high throughput experimentation since they are able to generate picoliter, self-compartmentalized vessels inexpensively at kHz rates. Through integration with fast, sensitive and high resolution fluorescence spectroscopic methods, the large amounts of information generated within these systems can be efficiently extracted, harnessed and utilized.
JoVE General
Extracting DNA from the Gut Microbes of the Termite (Zootermopsis Angusticollis) and Visualizing Gut Microbes
Department of Environmental Science and Engineering, California Institute of Technology - Caltech
This video illustrates the technique for extracting DNA from the species of microbes resident in the termite hindgut. The preparation of a wet mount slide, which is useful for visualizing the gut microbial community is also illustrated, and a tour through the species-rich gut environment is given.
JoVE General
A PCR-based Genotyping Method to Distinguish Between Wild-type and Ornamental Varieties of Imperata cylindrica
1Department of Biological Sciences, The University of Alabama, Huntsville, 2USDA-APHIS-PPQ, Center for Plant Health Science and Technology
We provide a cost-effective and rapid molecular genotyping protocol that employs variety-specific PCR primers that target DNA sequence differences within the chloroplast trnL-F spacer region to differentiate between varieties of Imperata cylindrica (cogongrass) that cannot be distinguished by morphology alone. These varieties include the federally listed noxious weed, cogongrass and closely-related, wide-spread ornamental variety, I. cylindrica var. koenigii (Japanese blood grass).
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.
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