2bfx
From Proteopedia
Mechanism of Aurora-B activation by INCENP and inhibition by Hesperadin.
Structural highlights
FunctionAUKBA_XENLA Serine/threonine-protein kinase component of the chromosomal passenger complex (CPC), a complex that acts as a key regulator of mitosis. The CPC complex has essential functions at the centromere in ensuring correct chromosome alignment and segregation and is required for chromatin-induced microtubule stabilization and spindle assembly. Involved in the bipolar attachment of spindle microtubules to kinetochores and is a key regulator for the onset of cytokinesis during mitosis. Required for central/midzone spindle assembly and cleavage furrow formation. Phosphorylates 'Ser-10' of histone H3 during mitosis.[1] [2] [3] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAurora family serine/threonine kinases control mitotic progression, and their deregulation is implicated in tumorigenesis. Aurora A and Aurora B, the best-characterized members of mammalian Aurora kinases, are approximately 60% identical but bind to unrelated activating subunits. The structure of the complex of Aurora A with the TPX2 activator has been reported previously. Here, we report the crystal structure of Aurora B in complex with the IN-box segment of the inner centromere protein (INCENP) activator and with the small molecule inhibitor Hesperadin. The Aurora B:INCENP complex is remarkably different from the Aurora A:TPX2 complex. INCENP forms a crown around the small lobe of Aurora B and induces the active conformation of the T loop allosterically. The structure represents an intermediate state of activation of Aurora B in which the Aurora B C-terminal segment stabilizes an open conformation of the catalytic cleft, and a critical ion pair in the kinase active site is impaired. Phosphorylation of two serines in the carboxyl terminus of INCENP generates the fully active kinase. Mechanism of Aurora B activation by INCENP and inhibition by hesperadin.,Sessa F, Mapelli M, Ciferri C, Tarricone C, Areces LB, Schneider TR, Stukenberg PT, Musacchio A Mol Cell. 2005 Apr 29;18(3):379-91. PMID:15866179[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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