Figure 4

Schematic representations of intein-mediated protein labeling. POI is protein of interest. In (A), the complementary pink shapes represent the ligand and its receptor. In (B), 'off’ and 'on’ indicate conditional expression states from a plasmid, with the proteins in black ¹⁵ N labeled and those in blue or red are not labeled. In (C), the conversion of the star from clear to yellow indicates induction of fluorescence.