The Claremont Colleges 8 articles published in JoVE Biology Identification of Novel Regulators of Plant Transpiration by Large-Scale Thermal Imaging Screening in Helianthus Annuus Konnie Guo*1, Peter Mellinger*1, Vy Doan1, Jeffrey Allen1, Ross N. Pringle1, Fabien Jammes1 1Department of Biology and Program in Molecular Biology, Pomona College We provide a method for identifying modulators of foliar transpiration by large-scale screening of a compound library. Behavior Operant Conditioning Task to Measure Song Preference in Zebra Finches Melissa J. Coleman1, David Saxon1, Anastasia Robbins1, Natalie Lillie1, Nancy F. Day2 1W.M. Keck Science Department, Claremont McKenna College – Pitzer College – Scripps College, 2Department of Psychology, Whitman College We describe a technique to evaluate song preference in zebra finches. Females are placed in a two-chambered cage and song preference is measured by the number of times she triggers the playback of one song by landing on a perch within one chamber, compared with triggering a different song in the second chamber. Perch landings are counted using infrared sensors. Environment Laser-Induced Fluorescence Emission (L.I.F.E.) as Novel Non-Invasive Tool for In-Situ Measurements of Biomarkers in Cryospheric Habitats Klemens Weisleitner1,2, Lars Hunger3, Christoph Kohstall4, Albert Frisch5, Michael C. Storrie-Lombardi6, Birgit Sattler1,2 1Institute of Ecology, University of Innsbruck, 2Austrian Polar Research Institute, University of Vienna, 3BrainLinks-BrainTools, Bernstein Center Freiburg, 4Atom Science, Kasevich Lab, Stanford University, 5Institute of Experimental Physics, University of Innsbruck, 6Department of Physics, Extraterrestrial Vehicle Instruments Laboratory, Harvey Mudd College Carbon fluxes in the cryosphere are hardly assessed yet but are crucial regarding climate change. Here we show a novel prototype device that captures the phototrophic potential in supraglacial environments based on laser-induced fluorescence emission (L.I.F.E.) technology offering high spectral and spatial resolution data under in situ conditions. Engineering Drawing and Hydrophobicity-patterning Long Polydimethylsiloxane Silicone Filaments Katherine Snell1, Isabelle Lopez2, Brandon Louie1, Roxanna Kiessling1, Babak Sanii1,2,3 1Keck Science Department, Claremont McKenna College, 2Keck Science Department, Scripps College, 3Keck Science Department, Pitzer College Here, we present a protocol to produce long filaments of polydimethylsiloxane (PDMS) silicone by gravity-drawing through a furnace. Filaments are on the order of hundreds of micrometers in diameter and tens of centimeters in length and are hydrophobically patternable via an Arduino-controlled corona discharge system. Biochemistry DNA Polymerase Activity Assay Using Near-infrared Fluorescent Labeled DNA Visualized by Acrylamide Gel Electrophoresis Eliza L. Lewis1, Aaron M. Leconte1 1Department of Chemistry, W.M. Keck Science Department of Claremont Mckenna, Pitzer, and Scripps College This protocol describes the characterization of DNA polymerase synthesis of modified DNA through observation of changes to near-infrared fluorescently labeled DNA using gel electrophoresis and gel imaging. Acrylamide gels are used for high resolution imaging of the separation of short nucleic acids, which migrate at different rates depending on size. Immunology and Infection Detection of Trypanosoma brucei Variant Surface Glycoprotein Switching by Magnetic Activated Cell Sorting and Flow Cytometry Danae Schulz1,2, Monica R. Mugnier1, Catherine E. Boothroyd1,3, F. Nina Papavasiliou1 1Laboratory of Lymphocyte Biology, Rockefeller University, 2Department of Biology, Harvey Mudd College, 3Masters School African trypanosomes grown in vitro undergo antigenic variation at a low rate, such that populations are made up of parasites expressing a dominant variant surface glycoprotein (VSG) type and a small population of "switched" variants. This protocol describes a fast method for detecting and quantifying these populations. Neuroscience Optical Clearing of the Mouse Central Nervous System Using Passive CLARITY Dustin G. Roberts1, Hadley B. Johnsonbaugh1, Rory D. Spence2, Allan MacKenzie-Graham1 1Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, 2W.M. Keck Science Department, Claremont McKenna, Pitzer & Scripps Colleges Optical clearing techniques are revolutionizing the way tissues are visualized. In this report we describe modifications of the original Clear Lipid-exchanged Acrylamide-hybridized Rigid Imaging-compatible Tissue-hYdrogel (CLARITY) protocol that yields more consistent and less expensive results. Biology Simple Method for Fluorescence DNA In Situ Hybridization to Squashed Chromosomes Amanda M. Larracuente1, Patrick M. Ferree2 1Department of Biology, University of Rochester, 2W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges Here, we present a simple method for performing fluorescence DNA in situ hybridization (DNA ISH) to visualize repetitive heterochromatic sequences on slide-mounted chromosomes. The method requires minimal reagents and it is versatile for use with short or long probes, different tissues, and detection with fluorescence or non-fluorescence-based signals.