Michael Caterina recalls a graduate student in David Julius' University of California, San Francisco lab who often brought his collection of bottled hot sauces to lab parties, for tasting with guacamole and chips. But the lab's interest in capsaicin goes beyond social gatherings.
Julius started out in yeast genetics, but decided as a postdoc to switch to neuroscience. "I started reading and becoming more and more interested in the biology of the sensory neurons involved in pain," he says. He also became interested in the idea of using natural products, such as capsaicin, to identify molecular components of the pain pathway.
At the time, the defining hallmark of these neurons was sensitivity to capsaicin and other vanilloid compounds. So he decided to take a pharmacological approach and identify the capsaicin receptor by expression cloning. "But what really made it happen," says Julius, was the development of a calcium imaging...