A Sealed Preparation for Long-Term Observations of Cultured Cells This protocol describes a sealed preparation that allows the continuous long-term observation of cultured mammalian cells on upright or inverted microscopes without environmental CO2 control. The preparation allows for optical conditions consistent with high-quality imaging and good cell viability for at least 100 hours.
Chambers for Examination of Live Cells under Mechanical Stress Protocol Manual measurement and manipulation of the cell surface requires access to the cells, usually in an open chamber. Temperature-controlled chambers or stage inserts are preferred for maintaining physiological activity during the experiment. For example, heated culture dishes with coverslip glass bottoms (Bioptechs) permit high-resolution fluorescence microscopy of living cells during force application.
Culture Chambers for Live-Cell Imaging Specimen chambers have had many designs published over the years describing systems that offer excellent optical properties while allowing specimens to be maintained for varying amounts of time. Ranging in complexity from the simple preparation of a sealed coverslip on a microscope slide to sophisticated perfusion chambers that enable tight control of virtually all environmental variables culture chambers are designed to to allow living specimens to be observed with minimal invasion at high res.
Design, Synthesis, and Characterization of Caged Compounds When choosing a particular molecule for photoactivation studies, it is necessary to have some structural knowledge of the molecule in order to design an appropriately caged species that will retain its biological inactivity until uncaging is effected. Includes synthesis of caged peptides or proteins.
Imaging of Organelle Membrane Systems and Membrane Traffic in Living Cells Using confocal laser-scanning microscope & GFP fusion proteins in time-lapse imaging to visualize the behavior of organelles and to track membrane-bound transport intermediates that bud off from organelles. Practical issues related to construction & expression of GFP fusion proteins are discussed. Essential for optimizing the brightness and expression levels of GFP fusion proteins so that intracellular membrane-bound structures containing these fusion proteins can be readily visualized.
Introduction to Live-Cell Imaging Techniques Live-cell imaging techniques provide critical insight into the fundamental nature of cellular & tissue function, especially due to the rapid advances that are currently being witnessed in fluorescent protein & synthetic fluorophore technology. Because of these advances, live-cell imaging has become a requisite analytical tool in most cell biology labs. Includes: Maintaining Live Cells on the Microscope Stage; Live-Cell Imaging Culture Chambers; Optical System and Detector Requirements etc.
Live Single-Cell Fura-2 Measurements to Determine the Intracellular Free Calcium This protocol describes a method to assess concentrations of free cytoplasmic calcium, [Ca2+]i, for cultured adherent RAW 264.7 cells in an 8-well coverglass. This objective is accomplished using the Ca2+-sensitive fluorescent dye, fura-2
acetoxymethyl (AM), which permeates cell membranes as an ester and is hydrolyzed in the cell to its Ca2+-sensitive acidic form. Fluorescence for the adherent cells is measured over time with cells that have been washed free of extracellular dye.
Live-Cell Imaging of GFP in Plants GFP serves as a molecular marker that can be imaged dynamically in living cells, both in its native form & as a fusion to other proteins. For GFP imaging, plants present the challenge of autofluorescence from chlorophyll, lignified cell walls, vacuolar contents, and other cell materials, all of which can obscure the GFP signal. Maximizing the signal-to-noise ratio is a major concern, and careful consideration should be given to the choice of tissue imaged, GFP expression level, etc.
Maintaining Live Cells on the Microscope Stage Live-cell imaging techniques provide a critical insight into the fundamental nature of cellular and tissue function, especially due to the rapid advances that are currently being witnessed in fluorescent protein and synthetic fluorophore technology. Because of these advances, live-cell imaging has become a requisite analytical tool in most cell biology laboratories.
Membrane Trafficking and Organelle Reagents Several common drugs, their targets, and protocols are described for studying organelle distribution and trafficking. The drugs are readily available from general suppliers, including Sigma, Roche, and Calbiochem.
Photoactivation-Based Labeling and In Vivo Tracking of RNA Molecules in the Nucleus This protocol describes a method for observing and measuring the movement of RNA molecules in the nucleus of living mammalian cells. Caged fluorescein-labeled DNA oligonucleotides are introduced into living mammalian cells, where they demonstrably hybridize to complementary RNA. After site-specific photoactivation at desired sites within the cell, the RNA movements away from those sites are followed and digitally recorded using a rapid acquisition microscopy system.