title: Molecular mechanism of Aurora A kinase autophosphorylation and its allosteric activation by TPX2.
abstract: We elucidate the molecular mechanisms of two distinct activation strategies (autophosphorylation and TPX2-mediated activation) in human Aurora A kinase. Classic allosteric activation is in play where either activation loop phosphorylation or TPX2 binding to a conserved hydrophobic groove shifts the equilibrium far towards the active conformation. We resolve the controversy about the mechanism of autophosphorylation by demonstrating intermolecular autophosphorylation in a long-lived dimer by combining X-ray crystallography with functional assays. We then address the allosteric activation by TPX2 through activity assays and the crystal structure of a domain-swapped dimer of dephosphorylated Aurora A and TPX2(1-25). While autophosphorylation is the key regulatory mechanism in the centrosomes in the early stages of mitosis, allosteric activation by TPX2 of dephosphorylated Aurora A could be at play in the spindle microtubules. The mechanistic insights into autophosphorylation and allosteric activation by TPX2 binding proposed here, may have implications for understanding regulation of other protein kinases.DOI: http://dx.doi.org/10.7554/eLife.02667.001.
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.
authors.forename: Adelajda
authors.initials: A
authors.lastname: Zorba
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Buosi
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.
authors.forename: Steffen
authors.initials: S
authors.lastname: Kutter
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.
authors.forename: Nadja
authors.initials: N
authors.lastname: Kern
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.
authors.forename: Francesco
authors.initials: F
authors.lastname: Pontiggia
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Cho
authors.affiliation: Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, United States dkern@brandeis.edu.
authors.forename: Dorothee
authors.initials: D
authors.lastname: Kern
mesh_terms: D000494:Allosteric Regulation; D064096:Aurora Kinase A / Q000737:chemistry / Q000378:metabolism*; D055162:Biocatalysis; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D006801:Humans; D007700:Kinetics; D008869:Microtubule-Associated Proteins / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D050505:Mutant Proteins / Q000737:chemistry / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D010769:Phosphothreonine / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D055503:Protein Multimerization; D055550:Protein Stability; D017434:Protein Structure, Tertiary; D012996:Solutions; D013379:Substrate Specificity
chemical_list: D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D050505:Mutant Proteins; D009687:Nuclear Proteins; D012996:Solutions; C122167:TPX2 protein, human; D010769:Phosphothreonine; D064096:Aurora Kinase A
keywords: activation; kinase; mechanism