title: Cnn1 inhibits the interactions between the KMN complexes of the yeast kinetochore.
abstract: Kinetochores attach the replicated chromosomes to the mitotic spindle and orchestrate their transmission to the daughter cells. Kinetochore-spindle binding and chromosome segregation are mediated by the multi-copy KNL1(Spc105), MIS12(Mtw1) and NDC80(Ndc80) complexes that form the so-called KMN network. KMN-spindle attachment is regulated by the Aurora B(Ipl1) and MPS1(Mps1) kinases. It is unclear whether other mechanisms exist that support KMN activity during the cell cycle. Using budding yeast, we show that kinetochore protein Cnn1 localizes to the base of the Ndc80 complex and promotes a functionally competent configuration of the KMN network. Cnn1 regulates KMN activity in a spatiotemporal manner by inhibiting the interaction between its complexes. Cnn1 activity peaks in anaphase and is driven by the Cdc28, Mps1 and Ipl1 kinases.
authors.affiliation: European Institute of Oncology, Department of Experimental Oncology, Via Adamello 16, 20139 Milan, Italy.
authors.forename: Lucy J
authors.initials: LJ
authors.lastname: Bock
authors.forename: Cinzia
authors.initials: C
authors.lastname: Pagliuca
authors.forename: Norihiko
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Ryan A
authors.initials: RA
authors.lastname: Grove
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Oku
authors.forename: Kriti
authors.initials: K
authors.lastname: Shrestha
authors.forename: Claudio
authors.initials: C
authors.lastname: Alfieri
authors.forename: Cristina
authors.initials: C
authors.lastname: Golfieri
authors.forename: Amanda
authors.initials: A
authors.lastname: Oldani
authors.forename: Marianna
authors.initials: M
authors.lastname: Dal Maschio
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Bermejo
authors.forename: Tony R
authors.initials: TR
authors.lastname: Hazbun
authors.forename: Tomoyuki U
authors.initials: TU
authors.lastname: Tanaka
authors.forename: Peter
authors.initials: P
authors.lastname: De Wulf
mesh_terms: D000705:Anaphase; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D015825:Chromosomes, Fungal / Q000378:metabolism; D018386:Kinetochores / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D008941:Spindle Apparatus / Q000378:metabolism
chemical_list: D018797:Cell Cycle Proteins; C574223:Cnn1 protein, S cerevisiae; C120362:MTW1 protein, S cerevisiae; D008869:Microtubule-Associated Proteins; D029701:Saccharomyces cerevisiae Proteins; C546124:Spc105 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C093416:MPS1 protein, S cerevisiae