mCherry

mCherry is a fluorophore (a fluorescent protein) used as a marker when tagged to molecules and cell components. mCherry and the majority of red fluorescent proteins derive from the protein drFP583 (commonly known as DsRed) isolated from Discosoma sea anemones, while other fluorescent proteins in the green range are often variants of jellyfish GFP. DsRed is a tetramer optimally excited at 558 nm and has an emission maximum at 583 nm. However, the maturation of DsRed is slow, and proceeds through an intermediate chromophore stage where most of the fluorescence emission occurs in the green spectral region.^[1]

Through extensive mutagenesis of the tetrameric DsRed, the monomeric mCherry protein was derived with a smaller size and faster maturation and a greater photostability. mCherry is sometimes preferred to other fluorophores due to its colour, as well as its photostability compared to other monomeric fluorophores. The 'm' in the name denotes its monomer configuration, which may be of importance in experimental design (other variants may be prefixed with 'td' for tandem-dimer, for example).

Other fluorophores derived from DsRed belong to the mFruit family (e.g. mApple, mOrange and mRaspberry) and have different spectra and protein configurations and structures.^[1]

Properties

Recombinant mCherry is expressed and purified from transformed E. coli. The protein is a 28.8 kDa monomer of 236 amino acids with a peak fluorescent excitation and emission at 587 nm and 610 nm, respectively. It is stable and resistant to photobleaching. It matures quickly, with a t_0.5 of 15 minutes, allowing it to be visualised soon after translation.^[2]

References

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