STOCKHOLM: Two Americans, one of Chinese origin, and a Japanese scientist won the Nobel Prize in chemistry yesterday for discovering and developing a glowing jellyfish protein that revolutionized the ability to study disease and normal development in living organisms.

Americans Roger Tsien and Martin Chalfie, as well as Japan's Osamu Shimomura shared the prize for their work on green fluorescent protein (GFP), the Royal Swedish Academy of Sciences said.

Researchers worldwide now use GFP to track such processes as the development of brain cells, the growth of tumors and the spread of cancer cells. It has let them study nerve cell damage from Alzheimer's disease and see how insulin-producing beta cells arise in the pancreas of a growing embryo, for example.