Peter Hemmerich

Nuclear proteins can be introduced into living cells as fusion proteins (fp) tagged with fluorescent proteins such as enhanced green fluorescent protein (EGFP) or monomeric red fluorescent protein (mRFP). Depending on its function the nuclear protein(s) may occur diffusely in the nucleoplasm as well as in specific subnuclear structures or compartments. Mobility and interactions can be assessed by time-lapse microscopy, fluorescence correlation spectroscopy (FCS), fluorescence recovery (or redistribution) after photobleaching (FRAP), continuous photobleaching (CP), fluorescence resonance energy transfer (FRET), fluorescence lifetime imaging (FLIM) and fluorescence cross-correlation spectroscopy (FCCS).