Narrator: This is Science Today. The 2008 Nobel Prize for Chemisty recognized the work of researchers who built molecules that can track cellular function using glowing markers. Roger Tsien of the University of California, San Diego, who share the prestigious honor, says they developed Green Fluorescent Protein to measure calcium levels inside cells.
Tsien: Calcium controls an awful lot inside us. Every twitch of every muscle in our body, a lot of cases of secretion from glands, practically every time one of our neurons in the brain talks to another neuron, that's a tiny little squirt of calcium.
Narrator: The researchers went a step further and taught cells how to make their own dyes, creating what Tsien calls "molecular spies".
Tsien: You can really build that in from ground zero and even sent it to very specific places because we now know by molecular biology, how to put zipcodes on proteins and so we can send them wherever we want, pretty much - within some limitations and those proteins then had been trained from birth to tell us to be our eyes and ears.
Narrator: For Science Today, I'm Larissa Branin.