Wed Oct 8 21:59:36 PDT 2008
The Beauty of Jellyfish, Photo-Optic Nano-Technology, and GFP
Have you ever been mesmerized by the beauty of a jellyfish? Have you ever wondered where the glow of the jellyfish comes from?
Osamu Shimomura wondered, set about finding out, and in the process changed the way that researches explore the production of proteins throughout living creatures.
The 2008 Nobel Prize for chemistry was awarded to Osamu Shimomura, Martin Chalfie, and Roger Tsien. The molecule at the center of their prize, green fluorescent protein, also known as GFP, is shown below.
The motion of the jellyfish leads to the creation of calcium ions within the creature's cells.
The beautiful green glow of jellyfish is produced through a coupled interaction between two unique proteins.
The first, a protein named aequorin, produces blue light, when it reacts with the calcium ions released by cell motion. Then the blue light is converted to the beautiful green fluorescent jellyfish green glow by GFP.
As you can see from the image above, a GFP protein possesses a cylindrical structure. The center of the molecule contains the chemical species which convert blue light to green. This is the 'fluorophore' and it is well protected. The environment of the fluorophore has been designed by evolution to create the correct electrostatic environment and the right protection for the conversion of light from blue to green. As you might imagine for a delicate conversion, cleanliness and a high degree of control, are required.
The GFP protein is in effect a highly controlled photo-optic nano-particle which possesses the appropriate characteristics to allow it perform its assigned function. Although this might seem relatively advanced technology, GFP has been that way in jellyfish for hundreds of millions of years.
The properties of GFP allow it to be used to follow the transcription of genes. By inserting the code for GFP into a DNA sequence, researches can see when and where a given gene is active, simply by shining a blue light at the creature and watching for the characteristic jellyfish glow in response.
So ancient photo-optic nano-technology allows for the rapid analysis of biological systems!