User:Daniel Mietchen/Sandbox/Cameleon

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Cameleons are Förster Resonance Energy Transfer (FRET) based indicators in which two fluorescent proteins, CFP and YFP (or circularly permuted variants of YFP), are linked together by the calcium-binding protein calmodulin and a calmodulin binding peptide. Binding of Ca2+ to these calcium-responsive elements alters the distance between the two fluorophores, hence the efficiency of FRET, allowing a quantitative measurement of Ca2+ dynamics [21].