Green fluorescent protein (GFP) is a fluorescent molecule that is found in the jellyfish Aequorea victoria. Isolated in 1961 and cloned in 1992, GFP has become a popular reporter molecule for gene expression in both mammalian and nonmammalian systems. Some modifications of GFP have resulted in the creation of an important class of reporter molecules which provides superior monitoring capabilities to those of other reporters such as luciferase or alkaline phosphatase. GFP can also be used as a nontoxic reporter in whole organisms.
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