“For discoveries concerning channels in cell membranes,” as the Royal Swedish Academy of Sciences put it, two Americans have won this year’s Nobel Prize in Chemistry. Peter Agre of the Johns Hopkins School of Medicine in Baltimore earned his half of the prize for discovering water channels. Roderick MacKinnon of the Rockefeller University in New York City earned his half for structural and mechanistic studies of ion channels.
Water channels span cell membranes in our kidneys, eyes, sweat glands, and other body parts. Bacteria, plants, and invertebrates have water channels, too. But until Agre’s discovery, no one had isolated the molecules that form the channels. Ion channels help regulate the electrostatic potential of cells and mediate the transmission of nerve signals. MacKinnon was the first to determine an ion channel’s atomic structure and to figure out how the channel works.
Cells need specialized channels to import and export ions because...
