Protein quantification in situ by fluorescence resonance energy transfer in living cells Method - protein interactions

The present invention discloses a method for determining the interaction energy transfer method of the first cell to a second protein if the protein by the presence of fluorescence resonance. The method comprises: (a) expressing a first fusion protein and a second fusion protein in the cell, wherein the first fusion protein comprises a first protein and a closable first donor fluorescent protein, said second fusion and a second protein comprising a protein as an acceptor second fluorescent protein may be closed; (2) may be closed in the first and second fluorescent proteins are fluorescent proteins may be closed to open, and the lower three conditions individually opened, respectively, in three species under the conditions of excitation light and the emitted light is detected fluorescence of the cells in order to obtain an absolute value of a data set consisting of a fluorescent. (3) based on the data set, determining a parameter value FR, and FR based on the obtained parameter values ​​to determine whether there is between the first and the second protein-protein interactions.