Cell cycle control of spindle pole body duplication and splitting by Sfi1 and Cdc31 in fission yeast.
Spindle pole biogenesis and segregation are tightly coordinated to produce a bipolar mitotic spindle. In yeasts, the spindle pole body (SPB) half-bridge composed of Sfi1 and Cdc31 duplicates to promote the biogenesis of a second SPB. Sfi1 accumulates at the half-bridge in two phases in Schizosaccharomyces pombe, from anaphase to early septation and throughout G2 phase. We found that the function of Sfi1-Cdc31 in SPB duplication is accomplished before septation ends and G2 accumulation starts. Thus, Sfi1 early accumulation at mitotic exit might correspond to half-bridge duplication. We further show that Cdc31 phosphorylation on serine 15 in a Cdk1 (encoded by cdc2) consensus site is required for the dissociation of a significant pool of Sfi1 from the bridge and timely segregation of SPBs at mitotic onset. This suggests that the Cdc31 N-terminus modulates the stability of Sfi1-Cdc31 arrays in fission yeast, and impacts on the timing of establishment of spindle bipolarity.
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France.
Imène B
IB
Bouhlel
Tokyo 169-8050, Japan.
Midori
M
Ohta
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France.
Adeline
A
Mayeux
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France.
Nicole
N
Bordes
Institut Curie, Centre de Recherche F-75248 Paris, France.
Florent
F
Dingli
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France.
Jérôme
J
Boulanger
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France.
Guilhem
G
Velve Casquillas
Institut Curie, Centre de Recherche F-75248 Paris, France.
Damarys
D
Loew
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France.
Phong T
PT
Tran
Tokyo 169-8050, Japan.
Masamitsu
M
Sato
Institut Curie, Centre de Recherche F-75248 Paris, France CNRS UMR144 F-75248 Paris, France anne.paoletti@curie.fr.
Anne
A
Paoletti
D016203:CDC2 Protein Kinase / Q000502:physiology; D002135:Calcium-Binding Proteins / Q000502:physiology*; D002148:Calmodulin-Binding Proteins / Q000502:physiology*; D059447:Cell Cycle Checkpoints; D018797:Cell Cycle Proteins / Q000502:physiology*; D048749:Cytokinesis; D008938:Mitosis; D012568:Schizosaccharomyces / Q000166:cytology*; D029702:Schizosaccharomyces pombe Proteins / Q000502:physiology*; D064048:Spindle Pole Bodies / Q000502:physiology*
D002135:Calcium-Binding Proteins; D002148:Calmodulin-Binding Proteins; D018797:Cell Cycle Proteins; D029702:Schizosaccharomyces pombe Proteins; C000598233:Sfi1 protein, S pombe; C489994:cdc31 protein, S pombe; D016203:CDC2 Protein Kinase; C469447:cdc2 protein, S pombe
Cell Cycle; Centrosome; Mitotic spindle; SPB