Molecular basis for the activation of Aurora A and Plk1 kinases during mitotic entry

ABSTRACT: The evolutionarily conserved, intrinsically disordered protein Bora is critical for initiating the activation of mitotic kinases. Once phosphorylated at Ser112 by Cyclin A-Cdk1 kinase, phospho-Bora activates unphosphorylated Aurora A kinase (AURKA), directing it towards Polo-like kinase 1 (Plk1), thus promoting Cyclin B-Cdk1 activation and mitotic entry. Here, by combining structural modelling and in vitro assays, we provide evidence that Bora wraps around the N-terminal lobe of AURKA to position its phospho-Ser112 near AURKA's T-loop, mimicking T-loop phosphorylation. Additionally, Bora transiently interacts with the ᵬ2;C helix of the Plk1 kinase domain through a conserved motif, guiding AURKA activity towards the Plk1 T-loop, which is otherwise impervious to phosphorylation by AURKA. We

SUBMITTER: Anaïs Pillan 

PROVIDER: S-SCDT-10_1038-S44318-025-00679-8 | biostudies-other |

REPOSITORIES: biostudies-other