mCherry is a 28.8 kDa fluorescent protein expressed and purified from transformed E. coli. It is a second generation red fluorescent protein derived from naturally-occuring fluorescent proteins in Anthozoa. mCherry offers emission is the red spectrum, which is less phototoxic to cells. It also offers brighness and photostability, making it the fluorescent protein of choice for in vivo and in vitro cell imaging.
Davidson, M.W. et al. (2009) Engineered fluorescent proteins: innovations and applications. Nature Methods. 6, 713-17.