title: Allosteric modulation of AURKA kinase activity by a small-molecule inhibitor of its protein-protein interaction with TPX2.
abstract: The essential mitotic kinase Aurora A (AURKA) is controlled during cell cycle progression via two distinct mechanisms. Following activation loop autophosphorylation early in mitosis when it localizes to centrosomes, AURKA is allosterically activated on the mitotic spindle via binding to the microtubule-associated protein, TPX2. Here, we report the discovery of AurkinA, a novel chemical inhibitor of the AURKA-TPX2 interaction, which acts via an unexpected structural mechanism to inhibit AURKA activity and mitotic localization. In crystal structures, AurkinA binds to a hydrophobic pocket (the 'Y pocket') that normally accommodates a conserved Tyr-Ser-Tyr motif from TPX2, blocking the AURKA-TPX2 interaction. AurkinA binding to the Y- pocket induces structural changes in AURKA that inhibit catalytic activity in vitro and in cells, without affecting ATP binding to the active site, defining a novel mechanism of allosteric inhibition. Consistent with this mechanism, cells exposed to AurkinA mislocalise AURKA from mitotic spindle microtubules. Thus, our findings provide fresh insight into the catalytic mechanism of AURKA, and identify a key structural feature as the target for a new class of dual-mode AURKA inhibitors, with implications for the chemical biology and selective therapeutic targeting of structurally related kinases.
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.|Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: Matej
authors.initials: M
authors.lastname: Janeček
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Old Addenbrooke's Site, Cambridge CB2 1GA.
authors.forename: Maxim
authors.initials: M
authors.lastname: Rossmann
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Pooja
authors.initials: P
authors.lastname: Sharma
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Amy
authors.initials: A
authors.lastname: Emery
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: David J
authors.initials: DJ
authors.lastname: Huggins
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Simon R
authors.initials: SR
authors.lastname: Stockwell
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: Jamie E
authors.initials: JE
authors.lastname: Stokes
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: Yaw S
authors.initials: YS
authors.lastname: Tan
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Estrella Guarino
authors.initials: EG
authors.lastname: Almeida
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Bryn
authors.initials: B
authors.lastname: Hardwick
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Ana J
authors.initials: AJ
authors.lastname: Narvaez
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Old Addenbrooke's Site, Cambridge CB2 1GA.
authors.forename: Marko
authors.initials: M
authors.lastname: Hyvönen
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: David R
authors.initials: DR
authors.lastname: Spring
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Grahame J
authors.initials: GJ
authors.lastname: McKenzie
authors.affiliation: MRC Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Ashok R
authors.initials: AR
authors.lastname: Venkitaraman
mesh_terms: D064096:Aurora Kinase A / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D006367:HeLa Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008938:Mitosis / Q000187:drug effects; D009363:Neoplasm Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D060066:Protein Interaction Maps / Q000187:drug effects*; D011494:Protein Kinases / Q000378:metabolism*; D054852:Small Molecule Libraries / Q000494:pharmacology*; D008941:Spindle Apparatus / Q000187:drug effects
chemical_list: D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D054852:Small Molecule Libraries; D011494:Protein Kinases; D064096:Aurora Kinase A