<p>Researchers at Howard Hughes Medical Institutes Janelia Farm Research Campus, the National Institutes of Health, and Florida State University have developed and applied a new light microscopy technique that will allow them to determine the arrangement of proteins that make up the individual organelles, or structures, within a cell.</p>
<p>The microscope and the technology that make it possible are described in an article appearing on-line in the August 10 issue of Science Express. The technique was conceived by Eric Betzig, Ph.D., and Harald Hess, Ph.D. while working as independent inventors and later as investigators at Janelia Farm, which subsequently supported their effort on the project. Funding for the project was also provided by the NIH. Drs. Betzig and Hess built the microscope and demonstrated the method at the NIH, while working with Jennifer Lippincott-Schwartz, Ph.D. and her colleagues in the Cell Biology and Metabolism Branch of the National Institute of Child Health and Human Development. Also working on the project was Michael Davidson of the National High Magnetic Field Laboratory at Florida State University.</p>
<p>This is a major advance that will allow us to understand the fundamental organization of the key structures within a cell, said Elias A. Zerhouni, M.D., Director of the NIH. What researchers learn from the new microscopy technique will provide a broad foundation for understanding the complexity of how proteins, the building blocks of cells, interact in health and disease.</p>
<p>The new technique is known as photoactivated localization microscopy (PALM). It relies on the earlier pioneering effort of Dr. Lippincott-Schwartz and NIH Staff Scientist George Patterson, Ph.D. to develop a new class of molecules, called photoactivated fluorescent proteins, which emit green or yellow light when exposed to a laser, but only after being activated by brief exposure to violet light. The cell itself is coaxed to produce these molecules, which are then bound to specific proteins of interest, thereby optically marking the molecular constituents of specific cellular structures.</p>
<p>For more, see: <a href="http://www.nih.gov/news/pr/aug2006/nichd-10.htm%5B/url%5D">http://www.nih.gov/news/pr/aug2006/nichd-10.htm</a></p>