Micropunching Lithography for Generating Micro- and Submicron-patterns on Polymer Substrates
Mechanical and Aerospace Engineering, University of Texas at Arlington
A micropunching lithography approach is developed to generate micro- and submicron-patterns on top, sidewall and bottom surfaces of polymer substrates. It overcomes the obstacles of patterning conducting polymers and generating sidewall patterns. This method allows rapid fabrication of multiple features and is free of aggressive chemistry.
Competitive Homing Assays to Study Gut-tropic T Cell Migration
Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School
Competitive homing experiments allow to directly assessing the migratory properties of two different cell populations in a single mouse. Here we illustrate this procedure by comparing the migration of ex vivo-generated gut-tropic versus non-gut tropic T cells.
Determination of DNA Methylation of Imprinted Genes in Arabidopsis Endosperm
Department of Biology, Saint Louis University
Imprinting is a phenomenon in plant and mammal reproduction. DNA methylation plays an important role in mechanisms of imprinting. Isolating endosperm and determining methylation status of imprinted genes in Arabidopsis can be difficult. In this protocol, we describe how to isolate endosperm and determine methylation by bisulfite sequencing.
Single Oocyte Bisulfite Mutagenesis
1Department of Obstretrics & Gynaecology, Schulich School of Medicine and Dentistry, University of Western Ontario, 2Department of Biochemistry, Schulich School of Medicine and Dentistry, University of Western Ontario, 3Children's Health Research Institute
Bisulfite mutagenesis is the gold standard for analyzing DNA methylation. Our modified protocol allows for DNA methylation analysis at the single-cell level and was specifically designed for individual oocytes. It can also be used for cleavage-stage embryos.
Associated Chromosome Trap for Identifying Long-range DNA Interactions
Medical Service, VA Palo Alto Health Care System , Stanford University School of Medicine
The associated chromosome trap (ACT) assay is a novel unbiased method for identifying long-range DNA interactions. The characterization of long range DNA interactions will allow us to determine the relationship of nuclear architecture to gene expression in both normal physiology and in diseased states.
Generation of Mice Derived from Induced Pluripotent Stem Cells
1Dorris Neuroscience Center & Department of Cell Biology, The Scripps Research Institute, 2Mouse Genetics Core Facility, The Scripps Research Institute
Generating induced pluripotent stem cell (iPSC) lines produces lines of differing developmental potential even when they pass standard tests for pluripotency. Here we describe a protocol to produce mice derived entirely from iPSCs, which defines the iPSC lines as possessing full pluripotency1.
Chromatin Isolation by RNA Purification (ChIRP)
ChIRP is a novel and rapid technique to map genomic binding sites of long noncoding RNAs (lncRNAs). The method takes advantage of the specificity of anti-sense tiling oligonucleotides to allow the enumeration of lncRNA-bound genomic sites.
Nanomoulding of Functional Materials, a Versatile Complementary Pattern Replication Method to Nanoimprinting
1Institute of Microengineering (IMT), Photovoltaics and Thin Film Electronics Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), 2Department of Electrical Engineering and Computer Sciences, University of California, Berkeley
We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes.
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.
The Specification of Telencephalic Glutamatergic Neurons from Human Pluripotent Stem Cells
1Department of Neuroscience, The University of Connecticut Health Center, 2Department of Genetics and Developmental Biology, The University of Connecticut Health Center, 3Stem Cell Institute, The University of Connecticut Health Center
This procedure yields telencephalic neurons by going through checkpoints which are similar to those observed during human development. The cells are allowed to spontaneously differentiate, are exposed to factors which push them towards the neural lineage, are isolated, and are plated onto coverslips to allow for terminal differentiation and maturation.
A Zebrafish Model of Diabetes Mellitus and Metabolic Memory
1Dr. William M. Scholl College of Podiatric Medicine, Rosalind Franklin University of Medicine and Science, 2Chicago Medical School, Rosalind Franklin University of Medicine and Science
Metabolic memory is the phenomenon by which diabetic complications persist and progress unimpeded even after euglycemia is achieved pharmaceutically. Here we describe a diabetes mellitus zebrafish model which is unique in that it allows for the examination of the mitotically transmissible epigenetic components of metabolic memory in vivo.
Derivation of Mouse Trophoblast Stem Cells from Blastocysts
In this video, we demonstrate the isolation of mouse blastocysts and the derivation of trophoblast stem cells from blastocysts. We also describe conditions for maintenance of the stem cell property as well as induction of differentiation in culture.
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.
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.
Evaluation of the Spatial Distribution of γH2AX following Ionizing Radiation
1Epigenetics in Human Health and Disease, BakerIDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, 2Epigenomic Medicine, BakerIDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, 3Department of Pathology, University of Melbourne
Microscopic analysis of γH2AX foci, which form following the phosphorylation of H2AX at Ser-139 in response to DNA double-strand breaks, has become an invaluable tool in radiation biology. Here we used an antibody to mono-methylated histone H3 at lysine 4 as an epigenetic marker of actively transcribing euchromatin, to evaluate the spatial distribution of radiation-induced γH2AX formation within the nucleus.
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.
Assessing Somatic Hypermutation in Ramos B Cells after Overexpression or Knockdown of Specific Genes
Department of Immunology, Duke University
We describe how to perform retroviral or lentiviral infections of overexpression or shRNA-containing constructs in the human Ramos B-cell line and how to measure somatic hypermutation in these cells.
Hyperinsulinemic-euglycemic Clamps in Conscious, Unrestrained Mice
1Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute at Lake Nona, 2Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, 3Vanderbilt Mouse Metabolic Phenotyping Center, Vanderbilt University School of Medicine, 4Department of Pediatrics and Cellular and Integrative Physiology, Indiana University School of Medicine
The hyperinsulinemic-euglycemic clamp, or insulin clamp, is the gold standard for assessing insulin action in vivo. A method for performing insulin clamps in mice is described. This includes a method for arterial catheterization that permits experiments to be performed in conscious, unrestrained mice with minimal stress.
