You’ve already seen bioluminescence…even if you don’t realize it. Like the words fireplace, meatball, flatbread and blackbird, Green Fluorescent Protein has a name that lets you know what it does without having to know too much else about it. I imagine that the people who named mouthwash and bedroom were probably just very lazy, or at least not very creative. So sure, it seems like Osamu Shimomura might have phoned it in when he named GFP, but he has an excuse. He spent all of the 1960’s farming a million jellyfish to understand the cool biochemistry that was inside them. Most significantly, that aequorin from jellies produces light and then GFP absorbs it so that it can be reemitted at a fun, sassier green wavelength. Why would jellyfish want to do that? Dr. Shimomura didn’t care. He also didn’t care about what it could be used for. He had jellyfish to feed. Douglas Prasher did care.
Prasher had the insight that a fluorescent protein could be used as a reporter if it could be isolated and tagged to other proteins of interest. In 1992, he successfully cloned the gene for GFP and expressed it in e. coli. Prasher’s funding ran out and he left academia, but not before he shared the clone with Marty Chalfie’s group at Columbia, presumably hoping that one day it would lead to a Nobel Prize for one of both of them.
Things got real shortly thereafter in the world of fluorescent proteins, especially in Roger Tsien’s lab at UCSD. In the next few years, dozens of fluorescent proteins would be isolated, mutated and commercialized, leading to not just one, but countless revolutions in molecular biology. If PCR is the first tool you’d buy for your molecular biology toolbox—maybe like a hammer—fluorescent proteins would be one of the other really important tools. Like a drill? Another smaller backup hammer with the round end instead of a nail yanker? I’m not that handy, to be honest with you. Definitely one of the top tools though!
While this was happening, Douglas Prasher hopped from jobs as a geneticist at the USDA to contracting gigs NASA. In 2008, the Nobel Prize for medicine was awarded to Tsien, Chalfie and Shimomura. At the time of the award, Douglas Prasher was roommates with Pete Best. Haha! Not really: he worked as a courtesy shuttle driver for a Toyota dealership in Alabama. Soooo… yeah. Since then, Prasher has returned to science, including a stint at Tsien’s lab at UCSD. So everything’s good, I suppose.
So why do jellyfish produce light anyway? What’s the point if they don’t have eyes? Many bioluminescent organisms—and there are a lot of them—produce light to communicate with each other or attract prey. Some use it as camouflage, which is one of the reasons it’s helpful for organisms to produce light of various wavelengths, not just maximizing brightness. Most jellyfish use bioluminescence as a defense mechanism. A flash of light when bumped can temporarily blind the kind of extremely terrifying fish that populate the deep and dark depths. At slightly less horrible distances from the surface, some jellies can drop a glowing tentacle that serves as a glowing distraction as the organism makes a very slow, undulating escape. This sort of defense is familiar to those of us on the surface who may have seen a gecko drop its tail and make an awkward getaway. Or maybe you have a younger brother who continually reminds you of the time a neighbor’s scary dog approached the driveway and a nine-year-old future BMG Labtech employee pushed his younger brother to the ground and pumped his chubby legs as fast as he could in the direction of the approaching school bus.