US Embassy Sweden · CC BY 2.0

A biochemist who mapped how cells package and ship molecules internally — the vesicle trafficking system that moves hormones, neurotransmitters, and enzymes to exactly where they're needed inside a cell. The discovery, made with Randy Schekman and Thomas Südhof, explained a basic mechanism of biology that had been a black box, and won the three the 2013 Nobel Prize in Physiology or Medicine. Rothman has taught at Yale, Columbia, and University College London.