Julian Voss-Andreae’s GFP-based sculpture Steel Jellyfish (2006). The image shows the stainless-steel sculpture at Friday Harbor Laboratories on San Juan Island (Wash., USA), the place of GFP’s discovery.
What is green, glows and has become an indispensable tool in cell biology? And, it was discovered right here in the Pacific Northwest!
The Green Fluorescent Protein (GFP) was initially isolated in 1962 from the pacific jellyfish Aequorea victoriaby Dr. Osamu Shimomura at the University of Washington’s Friday Harbor Laboratories. By harvesting and dissecting out the bioluminescent rim of thousands of jellyfish and purifying a “squeezate” extract of the material, enough GFP could be isolated to study the protein in greater detail.
After characterizing its green fluorescent properties when exposed to UV light, Shimomura went on to investigate the chemistry of the GFP chromophore and, in 1979, determined that the highly fluorescent structure is constructed from amino-acids that are part of the protein structure itself.The breakthrough in developing GFP as a molecular tool came when Martin Chalfie, in collaboration with Douglas Prasher, isolated the gene for GFP from the jellyfish genome, determined its sequence, and inserted it into E. coli and the nematode worm C. elegan. These experiments proved that GFP produces the chromophore independent of the jellyfish, is non-toxic, and can be used to monitor cellular events in live animals.
GFP has gained a wide variety of uses in various biology fields and has been modified to act as a sub-cellular sensor in many ways (pH, temperature, calcium, protein-protein interaction). Combined with fluorescent proteins from other aquatic species (such as the red fluorescent protein dsRed from the sea coral Discosoma striata), the color spectrum of fluorescent proteins has been expanded to cover almost the entire visible spectrum. As red and far-red colored variants of fluorescent proteins can be illuminated within tissues non-invasively, these fluorescent proteins have been inserted into cancer cells, used as markers to track tumor growth & malignancy, and visualize tumor shrinkage in response to chemotherapy. (more…)