title: A FRET-based study reveals site-specific regulation of spindle position checkpoint proteins at yeast centrosomes.
abstract: The spindle position checkpoint (SPOC) is a spindle pole body (SPB, equivalent of mammalian centrosome) associated surveillance mechanism that halts mitotic exit upon spindle mis-orientation. Here, we monitored the interaction between SPB proteins and the SPOC component Bfa1 by FRET microscopy. We show that Bfa1 binds to the scaffold-protein Nud1 and the γ-tubulin receptor Spc72. Spindle misalignment specifically disrupts Bfa1-Spc72 interaction by a mechanism that requires the 14-3-3-family protein Bmh1 and the MARK/PAR-kinase Kin4. Dissociation of Bfa1 from Spc72 prevents the inhibitory phosphorylation of Bfa1 by the polo-like kinase Cdc5. We propose Spc72 as a regulatory hub that coordinates the activity of Kin4 and Cdc5 towards Bfa1. In addition, analysis of spc72∆ cells shows that a mitotic-exit-promoting dominant signal, which is triggered upon elongation of the spindle into the bud, overrides the SPOC. Our data reinforce the importance of daughter-cell-associated factors and centrosome-based regulations in mitotic exit and SPOC control.
authors.affiliation: DKFZ-ZMBH Alliance, German Cancer Research Centre, Heidelberg, Germany.
authors.forename: Yuliya
authors.initials: Y
authors.lastname: Gryaznova
authors.affiliation: DKFZ-ZMBH Alliance, German Cancer Research Centre, Heidelberg, Germany.|Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany.
authors.forename: Ayse Koca
authors.initials: AK
authors.lastname: Caydasi
authors.affiliation: DKFZ-ZMBH Alliance, Centre for Molecular Biology, Heidelberg, Germany.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Malengo
authors.affiliation: DKFZ-ZMBH Alliance, Centre for Molecular Biology, Heidelberg, Germany.
authors.forename: Victor
authors.initials: V
authors.lastname: Sourjik
authors.affiliation: DKFZ-ZMBH Alliance, German Cancer Research Centre, Heidelberg, Germany.|Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany.
authors.forename: Gislene
authors.identifier: 0000-0002-6519-4737
authors.initials: G
authors.lastname: Pereira
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism*; D031541:Fluorescence Resonance Energy Transfer; D008856:Microscopy, Fluorescence; D008938:Mitosis; D025941:Protein Interaction Mapping; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D064048:Spindle Pole Bodies / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D029701:Saccharomyces cerevisiae Proteins
keywords: S. cerevisiae; cell biology; centrosome/spindle pole body; checkpoint; mitosis