A cryptic hydrophobic pocket in the polo-box domain of the polo-like kinase PLK1 regulates substrate recognition and mitotic chromosome segregation

DOI: 10.1038/s41598-019-50702-2

Authors: Pooja Sharma (The Medical Research Council Cancer Unit, University of Cambridge) , Robert Mahen (The Medical Research Council Cancer Unit, University of Cambridge) , Maxim Rossmann (University of Cambridge) , Jamie E. Stokes (University of Cambridge) , Bryn Hardwick (The Medical Research Council Cancer Unit, University of Cambridge) , David J. Huggins (University of Cambridge) , Amy Emery (The Medical Research Council Cancer Unit, University of Cambridge) , Dominique L. Kunciw (University of Cambridge) , Marko Hyvonen (University of Cambridge) , David R. Spring (University of Cambridge) , Grahame J. Mckenzie (The Medical Research Council Cancer Unit, University of Cambridge) , Ashok R. Venkitaraman (The Medical Research Council Cancer Unit, University of Cambridge)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Scientific Reports , VOL 9

State: Published (Approved)
Published: November 2019
Diamond Proposal Number(s): 7141 , 9537

Abstract: The human polo-like kinase PLK1 coordinates mitotic chromosome segregation by phosphorylating multiple chromatin- and kinetochore-binding proteins. How PLK1 activity is directed to specific substrates via phosphopeptide recognition by its carboxyl-terminal polo-box domain (PBD) is poorly understood. Here, we combine molecular, structural and chemical biology to identify a determinant for PLK1 substrate recognition that is essential for proper chromosome segregation. We show that mutations ablating an evolutionarily conserved, Tyr-lined pocket in human PLK1 PBD trigger cellular anomalies in mitotic progression and timing. Tyr pocket mutations selectively impair PLK1 binding to the kinetochore phosphoprotein substrate PBIP1, but not to the centrosomal substrate NEDD1. Through a structure-guided approach, we develop a small-molecule inhibitor, Polotyrin, which occupies the Tyr pocket. Polotyrin recapitulates the mitotic defects caused by mutations in the Tyr pocket, further evidencing its essential function, and exemplifying a new approach for selective PLK1 inhibition. Thus, our findings support a model wherein substrate discrimination via the Tyr pocket in the human PLK1 PBD regulates mitotic chromosome segregation to preserve genome integrity.

Journal Keywords: Kinases; Kinetochores; Mitosis; Phosphoproteins; Small molecules

Subject Areas: Biology and Bio-materials, Chemistry


Instruments: I03-Macromolecular Crystallography , I24-Microfocus Macromolecular Crystallography

Added On: 14/11/2019 14:14

Documents:
s41598-019-50702-2.pdf

Discipline Tags:

Biochemistry Chemistry Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)