Fluorescent reporter proteins have become indispensible in molecular biology. Originally isolated from Aequorea victoria, a jellyfish, green fluorescent protein (GFP) has been widely used as molecular tag to study cellular processes such as protein synthesis and gene expression. Fluorescence resonance energy transfer (FRET) occurs between two chromophores in close proximity. FRET using GFP reporter tags can be used to study protein interactions. Other fluorescent proteins are available in different colors, with fluorescence in other areas of the spectrum. With multichannel detection technology, two-color fluorescence can be used, for example, in gels to identify two different proteins at the same time. Although fluorescent reporter tags can in some cases change the outcome of an experiment, overall they are minimally toxic to cells and easy to work with. Follow the links below to find the right fluorescent reporter for your needs.