Mass spectrometry-based phosphoproteomics of PCMD-1

PCMD-1 is a centriolar protein that stabilizes the pericentriolar material (PCM) scaffold in C. elegans. Our data show that CDK-1 primes PCMD-1 for PLK-1–dependent phosphorylation. Mutations in PLK-1 docking sites reduce PCMD-1 phosphorylation, leading to disorganized PCM, unstable centrosomes, and delayed centriole separation. These findings suggest that PCMD-1 phosphorylation is essential for tethering and maintaining PCM scaffold integrity during mitosis.