Jellyfish glow. It’s true and it’s all because of one protein.
A protein is a string of amino acids. Imagine a string of pearls, each pearl linked to the next in linear succession to form a beautiful necklace. The pearls are the building blocks for the necklace. Amino acids are the building blocks for a protein. If you string a few together you get a peptide; if you string a lot together you get a protein.
As a long string, free and loose, the protein isn’t doing much and certainly isn’t focusing on its chores. Sorry mom and dad. It needs to assume a particular shape in order to do any work. Free and loose it is essentially useless to the cell, but folded up and tightly bound it is ready for action.
What action? Depends on the protein. They fall into several categories, some quite distinctly and some hosting multiple labels. Much like music, really. Gustav Holst’s The Planets is unmistakably classical. Indigo Girls, however, could be considered rock, Indie, folk, and alternative. In music language, some proteins are strictly classical while others dabble in rock, Indie and folk.
In science language, some transport cargo – the hemoglobin protein carries oxygen, some are hormones like insulin, some are enzymes like monoamine oxidase (inhibitors of which are widespread in the pharmaceutical industry), some provide structure like keratin in hair or collagen in skin and muscles.
One kind of protein has a really cool job. Its job is to be fluorescent. Shine the right kind of light onto the protein and you’ve got yourself a glowing organism. Whatever your favorite color, there’s almost guaranteed a fluorescent protein for you.
The Nobel Prize for Chemistry in 2008 went out to Roger Tsien of UC San Diego, Martin Chalfie of Columbia University and Osamu Shimomura of Japan for the development of these fluorescent proteins. This work has led not only to a sizable color wheel but also a variety of glowing organisms. Monkey? Glows green. Mice? Green. Worm? Green. Cat? Glows red. Dog? Red. Fish? Green, red AND yellow.
The original source of the green fluorescent protein? Aequorea victoria. Also known as the jellyfish.