TagRFP is a monomeric red (orange) fluorescent protein generated from the wild-type RFP from sea anemone Entacmaea quadricolor [Merzlyak et al., 2007]. It possesses bright fluorescence with excitation/emission maxima at 555 and 584 nm, respectively. TagRFP is about three times brighter than mCherry protein [Shaner et al., 2004], which makes it the brightest monomeric red fluorescent protein available so far.

TagRFP is mainly intended for protein labeling and FRET applications. It can also be used for cell and organelle labeling and for tracking the promoter activity.