title: Autophosphorylation of a newly identified site of Aurora-B is indispensable for cytokinesis.
abstract: Mitotic kinases regulate cell division and its checkpoints, errors of which can lead to aneuploidy or genetic instability. One of these is Aurora-B, a key kinase that is required for chromosome alignment at the metaphase plate and for cytokinesis in mammalian cells. We report here that human Aurora-B is phosphorylated at Thr-232 through interaction with the inner centromere protein (INCENP) in vivo. The phosphorylation of Thr-232 occurs by means of an autophosphorylation mechanism, which is indispensable for the Aurora-B kinase activity. The activation of Aurora-B spatio-temporally correlated with the site-specific phosphorylation of its physiological substrates, histone H3 and vimentin. Overexpression of the TA mutant of Aurora-B, in which Thr-232 was changed into alanine, frequently induced multinuclearity in cells. These results indicate that the phosphorylation of Thr-232 is an essential regulatory mechanism for Aurora-B activation.
authors.affiliation: Division of Biochemistry, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya, Aichi 464-8681, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yasui
authors.forename: Takeshi
authors.initials: T
authors.lastname: Urano
authors.forename: Aie
authors.initials: A
authors.lastname: Kawajiri
authors.forename: Koh-ichi
authors.initials: K
authors.lastname: Nagata
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tatsuka
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Saya
authors.forename: Koichi
authors.initials: K
authors.lastname: Furukawa
authors.forename: Toshitada
authors.initials: T
authors.lastname: Takahashi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Izawa
authors.forename: Masaki
authors.initials: M
authors.lastname: Inagaki
mesh_terms: D000409:Alanine / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D064107:Aurora Kinase B; D064127:Aurora Kinases; D001665:Binding Sites; D019556:COS Cells; D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism; D002875:Chromosomes / Q000648:ultrastructure; D006367:HeLa Cells; D006657:Histones / Q000737:chemistry; D006801:Humans; D013058:Mass Spectrometry; D008856:Microscopy, Fluorescence; D008938:Mitosis; D008969:Molecular Sequence Data; D009154:Mutation; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D013912:Threonine / Q000737:chemistry; D013997:Time Factors; D014162:Transfection; D014746:Vimentin / Q000737:chemistry
chemical_list: D006657:Histones; D014746:Vimentin; D013912:Threonine; C576921:AURKB protein, human; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; D000409:Alanine