Elizabeth Blackburn of the University of California, San Francisco, was named the Nobel Prize winner in physiology or medicine for discovering how chromosomes are protected.
Blackburn will share one-third of the $1.4 million prize with Carol Greider of Johns Hopkins University and Jack Szostak of the Howard Hughes Medical Institute and Massachusetts General Hospital.
The trio found that chromosome-capping telomeres — which Blackburn has compared to the plastic ends of shoe laces — and the enzyme telomerase protect chromosomes as cells divide.
Blackburn and Szostak discovered that a unique DNA sequence in the telomeres protects the chromosomes from degradation while Blackburn and Greider identified telomerase, the enzyme that makes telomere DNA.
If the telomeres are shortened, cells age. Higher telomerase activity, meanwhile, maintains telomeres length.
The discoveries have an impact on cancer research as well as research into aging and other diseases. Blackburn and her UCSF colleagues have found, for example, that telomeres are worn down in people who are stressed for long periods of time, like a parent caring for a chronically ill child.
Blackburn is the fourth UCSF Nobel Prize winner, joining Stanley Prusiner, Harold Varmus and former chancellor J. Michael Bishop.
Blackburn, Greider and Szostak beat out other notable scientists, including Shinya Yamanaka of UCSF and the J. David Gladstone Institutes, whose work at Kyoto University in Japan produced an embryonic-like stem cell from adult stem cells.
Yamanaka last month won the Lasker Award, considered a precursor to a Nobel Prize. It is the same award that Blackburn, Greider and Szostak won in 2006.