The structure and function of fluorescent proteins.

The current complement of fluorescent proteins (FPs) contains color variants whose emission spectra span most of the visible spectrum, providing researchers with a versatile toolset of fluorescent probes for live cell imaging applications. FP family members generate their chromophores autocatalytically through a series of posttranslational modifications. The fluorescence characteristics of GFP-family members are influenced in important ways by the local microenvironment surrounding the chromophore. In this tutorial review, we first examine the molecular factors that influence the photophysical properties of FP family members and then briefly discuss some of the ways in which these fascinating proteins have been applied to the field of live cell imaging.