title: Tripin/hSgo2 recruits MCAK to the inner centromere to correct defective kinetochore attachments.
abstract: hSgo2 (previously annotated as Tripin) was recently reported to be a new inner centromere protein that is essential for centromere cohesion (Kitajima et al., 2006). In this study, we show that hSgo2 exhibits a dynamic distribution pattern, and that its localization depends on the BUB1 and Aurora B kinases. hSgo2 is concentrated at the inner centromere of unattached kinetochores, but extends toward the kinetochores that are under tension. This localization pattern is reminiscent of MCAK, which is a microtubule depolymerase that is believed to be a key component of the error correction mechanism at kinetochores. Indeed, we found that hSgo2 is essential for MCAK to localize to the centromere. Delocalization of MCAK accounts for why cells depleted of hSgo2 exhibit kinetochore attachment defects that go uncorrected, despite a transient delay in the onset of anaphase. Consequently, these cells exhibit a high frequency of lagging chromosomes when they enter anaphase. We confirmed that hSgo2 is associated with PP2A, and we propose that it contributes to the spatial regulation of MCAK activity within inner centromere and kinetochore.
authors.affiliation: Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
authors.forename: Haomin
authors.initials: H
authors.lastname: Huang
authors.forename: Jie
authors.initials: J
authors.lastname: Feng
authors.forename: Jakub
authors.initials: J
authors.lastname: Famulski
authors.forename: Jerome B
authors.initials: JB
authors.lastname: Rattner
authors.forename: Song Tao
authors.initials: ST
authors.lastname: Liu
authors.forename: Gary D
authors.initials: GD
authors.lastname: Kao
authors.forename: Ruth
authors.initials: R
authors.lastname: Muschel
authors.forename: Gordon K T
authors.initials: GK
authors.lastname: Chan
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Yen
mesh_terms: D000705:Anaphase / Q000502:physiology*; D064107:Aurora Kinase B; D064127:Aurora Kinases; D018797:Cell Cycle Proteins / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D016547:Kinesins / Q000378:metabolism*; D018386:Kinetochores / Q000378:metabolism* / Q000648:ultrastructure; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D021381:Protein Transport / Q000502:physiology
chemical_list: D018797:Cell Cycle Proteins; C091489:KIF2C protein, human; C510590:SGO2 protein, human; D011494:Protein Kinases; C576921:AURKB protein, human; D064107:Aurora Kinase B; D064127:Aurora Kinases; C584277:BUB1 protein, human; C090464:Bub1 spindle checkpoint protein; D017346:Protein Serine-Threonine Kinases; D010749:Phosphoprotein Phosphatases; D016547:Kinesins