Figure 1.

Schematic overview of Plk1 function. A. The Polo-Box Domain (PBD) mediates protein interactions with targets (X). These interactions are often enhanced by priming phosphorylation (yellow). This docking facilitates the phosphorylation (orange) of the same target or another target in the vicinity (Y) by the kinase domain (K_D). B. A competitive chemical inhibitor (red) of the PBD prevents Plk1 from interacting with its targets, thereby decreasing the efficiency of substrate phosphorylation by the K_D.