Analyzing Real‐Time Video Microscopy: The Dynamics and Geometry of Vesicles and Tubules in Endocytosis

Nicholas Hamilton1, Markus C. Kerr1, Kevin Burrage1, Rohan D. Teasdale1

1 ARC Centre in Bioinformatics Institute for Molecular Bioscience The University of Queensland, St. Lucia, Australia
Publication Name:  Current Protocols in Cell Biology
Unit Number:  Unit 4.16
DOI:  10.1002/0471143030.cb0416s35
Online Posting Date:  June, 2007
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With the advent of live cell imaging microscopy, new types of mathematical analyses and measurements are possible. Many of the real‐time movies of cellular processes are visually very compelling, but elementary analysis of changes over time of quantities such as surface area and volume often show that there is more to the data than meets the eye. This unit outlines a geometric modeling methodology and applies it to tubulation of vesicles during endocytosis. Using these principles, it has been possible to build better qualitative and quantitative understandings of the systems observed, as well as to make predictions about quantities such as ligand or solute concentration, vesicle pH, and membrane trafficked. The purpose is to outline a methodology for analyzing real‐time movies that has led to a greater appreciation of the changes that are occurring during the time frame of the real‐time video microscopy and how additional quantitative measurements allow for further hypotheses to be generated and tested.

Keywords: endocytosis; video microscopy; endosomal trafficking; membrane trafficking

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Table of Contents

  • Data and Measurement
  • Conservation of Surface Area
  • Measurement of Volume
  • Flux Across a Membrane, Solute Concentration, and pH Change
  • Pressure, Tension, and Morphology
  • Vesicle Fusion
  • Proportionality and Surface Area
  • Conclusions
  • Acknowledgements
  • Literature Cited
  • Figures
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Internet Resources
  The U.S. National Institutes of Health Web site for ImageJ written by W.S. Rasband and updated from 1997 to 2007.
  The T.I.L.L. Photonics Web site for the TILLvisION image analysis software.
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