Live cell imaging techniques are driving a revolution in biological research. Instead of viewing dead tissues and cells fixed at a particular stage of activity, scientists can now visualize dynamic changes as they happen, permitting a better understanding of biological processes. The revolution has been fueled by the implementation of genetically encoded fluorescent proteins, the subject of the 2008 Nobel Prize in Chemistry (http://nobelprize.org/nobel_prizes/chemistry/laureates/2008/press.html). The diverse array of applications benefiting from fluorescent proteins ranges from markers targeted at organelles and protein fusions designed to monitor intracellular dynamics to reporters of transcriptional regulation and in vivo probes for whole-body imaging and detection of cancer. Fluorescent proteins have enabled the creation of highly specific biosensors to monitor a wide range of intracellular phenomena, including pH and metal-ion concentration, protein kinase activity, apoptosis, membrane voltage, cyclic nucleotide signaling, and tracing neuronal pathways. In the December issue of Cold Spring Harbor Protocols (www.cshprotocols.org/TOCs/toc12_09.dtl), David Piston and colleagues (https://medschool.mc.vanderbilt.edu/piston_lab/) present “Fluorescent Protein Tracking and Detection: Fluorescent Protein Structure and Color Variants,” a comprehensive overview of the wide variety of fluorescent proteins that are currently available. As one of December’s featured articles, it is freely available on the journal’s website (http://cshprotocols.cshlp.org/cgi/content/full/2009/12/pdb.top63).
While obtaining data through live cell imaging has become a regular practice in many laboratories, performing detailed analyses on the data is often problematic. The application of computational image processing is still far from routine. Researchers need to determine which measurements are necessary and sufficient to characterize a system and they need to find the appropriate tools to extract these data. In “Computational Image Analysis of Cellular Dynamics: A Case Study Based on Particle Tracking,” Gaudenz Danuser (http://lccb.hms.harvard.edu/) and Khuloud Jaqaman (http://sorger.med.harvard.edu/people/khuloud-jaqaman/) introduce the basic concepts that make the application of computational image processing to live cell image data successful. The article is featured in the December issue of Cold Spring Harbor Protocols (www.cshprotocols.org/TOCs/toc12_09.dtl) and is freely available on the journal’s website (http://cshprotocols.cshlp.org/cgi/content/full/2009/12/pdb.top65).
Both articles are adapted from the forthcoming Live Cell Imaging: A Laboratory Manual, Second Edition (http://www.cshlpress.com/link/livecell2p.htm). Available later this month, the manual expands upon and extends the collection of established and evolving methods for studying dynamic changes in living cells and organisms presented in the well-known first edition.
Related: See my article on Rife a man who created a special microscope to view living cells in the late 1930’s and who, after years of research, supposedly used the scope along with another to cure cancer in rats and then in people.