The Royal Swedish Academy of Sciences says two Americans and a Japanese man have won the Nobel chemistry prize.

The academy says they shared the prize for the discovery and development of the green fluorescent protein, GFP, which was first seen in jellyfish.

The protein is a widely used laboratory tool to illuminate processes in living organisms, like development of brain cells or the spread of cancer cells.

The academy says the work of Japan's Osamu Shimomura and Americans Martin Chalfie and Roger Tsien has enabled "scientists to follow several different biological processes at the same time."

That means that researchers have been able to use GFP to track nerve cell damage from Alzheimer's disease or see how insulin-producing beta-cells are created in the pancreas of a growing embryo.

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