Cell cycle-dependent kinetochore localization of condensin complex in Saccharomyces cerevisiae.
In budding yeast mitosis is endonuclear and associated with a very limited condensation of the chromosomes. Despite this partial chromosomal condensation, condensin is conserved and essential for the Saccharomyces cerevisiae mitotic cycle. Here, we investigate the localization of condensin during the mitotic cycle. In addition to a constitutive association with rDNA, we have discovered that condensin is localized to the kinetochore in a cell cycle-dependent manner. Shortly after duplication of the spindle pole body, the yeast equivalent of the centrosome, we observed a local enrichment of condensin colocalizing with kinetochore components. This specific association is consistent with mutant phenotypes of chromosome loss and defective sister chromatid separation at anaphase. During a short period of the cell cycle, we observed, at the single cell level, a spatial proximity of condensin and a cohesin rosette, without colocalization. Furthermore, using a genetic screen we demonstrated that condensin localization at kinetochores is specifically impaired in a mutant for ulp2/smt4, an abundant SUMO protease. In conclusion, during chromosome segregation, we established a SUMO-dependent cell cycle-specific condensin concentration colocalizing with kinetochores.
Bachellier-Bassi
Sophie
S
Unité de Biologie Cellulaire du Noyau, CNRS URA 2582, Institut Pasteur, 25 rue du Dr Roux, 75724 Paris cedex 15, France. bachelli@pasteur.fr
Gadal
Olivier
O
Bourout
Gaëlle
G
Nehrbass
Ulf
U
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D002453:Cell Cycle; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004275:DNA, Ribosomal / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D018386:Kinetochores / Q000378:metabolism*; D008938:Mitosis; D046912:Multiprotein Complexes / Q000378:metabolism*; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D000097722:Cohesins
D000251:Adenosine Triphosphatases; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004275:DNA, Ribosomal; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D000097722:Cohesins; C108312:condensin complexes