Diving For Science 2005 Proceedings Of The American

Diving For Science 2005 Proceedings Of The American Academy Of Underwater Sciences
proteins in Aequorea victoria, a bioluminescent jellyfish (Morise et al., 1974), and is now
used to refer loosely to the entire family of related proteins, no matter what their color.
What is so special about GFP? Most natural fluorescence does not come directly from a
protein, but from other molecules that are attached after the protein has been made by the
cell. This means that in order to become fluorescent an organism would not only have to
make the right protein, but would also need to do some additional chemistry, having the right
substances available to the protein. What is magic about GFP is that the fluorescence comes
directly from the protein itself, with no additional chemistry needed. If a cell makes the
protein, it becomes fluorescent. This property makes GFP incredibly valuable for a wide
range of applications in biomedical research, where it serves as a marker for gene activity
(Chalfie et al., 1994). Several companies sell GFP's derived from corals and other organisms.
It is not necessary to harvest large numbers of corals from the reef to meet the demand. The
gene for the GFP can be transferred to bacteria, and colonies of bacteria can be used to grow
supplies of the gene.
Several researchers are using fluorescence equipment in the field to discover new fluorescing
proteins, and in the laboratory to work with the proteins. There is a need for new FP's in
order to have better properties, such as new colors, brighter fluorescence, improved
resistance to photobleaching, better compatibility for a wider range of experiments, and
more.
Discoveries
The exploration for fluorescence has already led to discoveries of scientific interest. As
noted above, the ability to find very small targets is already being applied to coral reef
recruitment research. The process of discovering more and more types of fluorescing
organisms is leading to greater understanding of evolutionary relationships.
In one instance our dive team happened upon a mantis shrimp (stomatopod) in its burrow in
just 2 m of water within a stone’s throw of the dock at a Bahamas research station. The
mantis shrimp had two bright yellow fluorescent spots on its back. Our video of the mantis
shrimp captured the interest of a researcher who specialized in their vision. This in turn led
to a 4-person collaborative effort to understand the significance of the fluorescence through
observation, measurement, and modeling. We were able to determine that the fluorescence
was a part of the animal’s visual threat response and published the results in Science (Mazel
et al., 2004).
Discoveries are easy to come by since so little as known. Applications are just now
emerging as more and more scientists begin to experiment with the technique. It is not
particularly difficult to learn and apply, with the major disadvantage being the need to do
much of the work at night. Beyond specific scientific applications, experiencing
fluorescence in the sea is a broadening of one's horizons. Fluorescence is a very real aspect
of the underwater world, one that relatively few divers have ever experienced. Seeing this
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