Roger Y. Tsien (1952–2016) was a pioneering American biochemist and Nobel Laureate. He studied at Churchill College, Cambridge, earning a Ph.D. in Physiology in 1977 under a Marshall Scholarship.
Tsien revolutionized biological imaging through his development of fluorescent calcium indicators and engineered rainbow-colored variants of green fluorescent protein (GFP), enabling unprecedented visualization of processes inside living cells. For these groundbreaking tools, he shared the 2008 Nobel Prize in Chemistry with Osamu Shimomura and Martin Chalfie.
Over his career, Tsien held appointments at UC Berkeley and UC San Diego, served as an HHMI Investigator, co-founded biotech companies like Aurora Biosciences and Senomyx, and authored over 100 patents. His honors include the Wolf Prize in Medicine, Rosenstiel Medal, Gairdner International Award, election to the U.S. National Academy of Sciences, and membership in the Royal Society. Learn more.