In vivo FLIM-FRET measurements of recombinant proteins expressed in filamentous fungi

Fluorescence imaging techniques are extremely powerful tools in cell biology, providing valuable insights into the structure and function of biomolecules in their native environments. In particular, the use of Förster resonance energy transfer (FRET) has become increasingly important to obtain information on interactions on the nanoscale, in turn providing insights into molecular behaviour inside living cells. This review describes the basic principles of FRET and fluorescence lifetime imaging microscopy (FLIM) and their application in analyses of protein interactions inside living fungal cells.