MUTANTS OF GREEN FLUORESCENT PROTEIN

摘要

The present invention provides novel engineered derivatives of green fluorescent protein (GFP) which have an amino acid sequence which is modifie d by amino acid substitution compared with the amino acid sequence of wild typ e Green Fluorescent Protein. The modified GFPs exhibit enhanced fluorescence relative to wtGFP when expressed in non-homologous cells at temperatures abo ve 30 ~C, and when excited at about 490 nm compared to the parent proteins, i.e . wtGFP. An example of a preferred protein is F64L-S175G-E222G-GFP. The modifi ed GFPs provide a means for detecting GFP reporters in mammalian cells at lower levels of expression and/or increased sensitivity relative to wtGFP. This greatly improves the usefulness of fluorescent proteins in studying cellular functions in living cells.