Martin Chalfie is a soft-spoken man with a relaxed way of describing complicated topics. He is a professor in the Biological Sciences Department at Columbia University, conducting research on the nervous system of worms. One day, almost twenty-five years ago, he walked into a casual lunchtime seminar in his department at Columbia to hear a lecture outside his field of research. An hour later he walked out with what turned out to be a million-dollar idea for a natural flashlight that would let him look inside living organisms to watch their biological processes in action. Chalfie’s insight was akin to the invention of the microscope, enabling researchers to see what had previously been invisible. In 2008, he received a Nobel Prize in Chemistry for his work.
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Something happened to him during the hour he spent at the seminar that started his path to the Nobel Prize. Chalfie was studying the nervous system of worms. The type of worms he investigated just happened to have translucent skin, an incidental feature that had played no part in his project up to that point. To study the neurons of worms, Chalfie’s assistants had to kill the worms in order to examine their tissues. Chalfie hadn’t given the methodology for running these experiments much thought because it was the standard way for researchers like him to do their work.
The speaker at the April 25, 1989, lunchtime talk, one of the regular Tuesday seminars arranged by his department, covered a range of issues that didn’t particularly interest Chalfie. Then, in the middle of the talk, the speaker described how jellyfish can produce visible light and are capable of bioluminescence. In 1962, a Japanese scientist discovered the protein that fluoresces to produce a green light in the jellyfish. When ultraviolet light is shined on the protein, it reacts by emitting green light.
That was Chalfie’s eureka moment. Suddenly, he understood that if he inserted the green fluorescent protein (GFP) into his transparent worms, he could shine ultraviolet light on it and see where the protein was spreading. He could track the cells into which he placed the GFP. He thought, “I work on this transparent animal, this is going to be terrific! I’ll be able to see the cells within the living animal.”
Chalfie doesn’t remember much about the rest of the lecture because he was so busy making notes about how he could use this GFP as a biological flashlight.
Today, these biological flashlights are a workhorse of molecular biology and a multimillion-dollar industry. Other researchers cloned the GFP so that technicians don’t have to chop up lots of jellyfish to extract it. The GFP now comes in additional colors, such as blue, cyan, and red.
This tidbit is from Seeing What Others Don't from Gary Klein.