Luciferase-YFP fusion tag with enhanced emission for single-cell luminescence imaging

Taking advantage of the phenomenon of bioluminescence resonance energy transfer ( BRET), we developed a bioluminescent probe composed of EYFP and Renilla reniformis luciferase ( RLuc) - BRET- based autoilluminated fluorescent protein on EYFP ( BAF- Y) - for near- real- time single- cell imaging. We show that BAF- Y exhibits enhanced RLuc luminescence intensity and appropriate subcellular distribution when it was fused to targeting- signal peptides or histone H2AX, thus allowing high spatial and temporal resolution microscopy of living cells.