Cep152 interacts with the cryptic Polo-box of Plk4 and is required for Plk4-induced centriole overduplication.

and Cdc25B, but not Cdc25C phosphatases have an effect on timing and efficiency of cyclin-kinase complex formation. Overexpression of Cdc25A or Cdc25B promotes earlier assembly and activation of Cdk1-cyclin B complexes, whereas repression of these phosphatases by short hairpin RNA has a reverse effect, leading to a substantial decrease in amounts of cyclin B-bound Cdk1 in G 2 and mitosis. Importantly, we find that Cdc25A overexpression leads to an activation of Cdk7 and increase in Thr 161 phosphorylation of Cdk1. In conclusion, our data suggest that complex assembly and dephosphorylation of Cdk1 at G 2 /M is tightly coupled and regulated by Cdc25 phosphatases.

MISP is a substrate of Plk1 and important for the stabilization of cortical and astral microtubule attachments to regulate mitotic spindle positioning.