GSE53856
Shugoshin biases chromosomes for biorientation through condensin recruitment to the pericentromere
To protect against aneuploidy, chromosomes must attach to microtubules from opposite poles (“biorientation”) prior to their segregation during mitosis. Biorientation relies on the correction of erroneous attachments by the aurora B kinase, which destabilizes kinetochore-microtubule attachments that lack tension. Incorrect attachments are also avoided because sister kinetochores are intrinsically biased towards capture by microtubules from opposite poles. Here we show that shugoshin acts as a pericentromeric adaptor that plays dual roles in biorientation in budding yeast. Shugoshin maintains the aurora B kinase at kinetochores that lack tension, thereby engaging the error correction machinery. Shugoshin also recruits the chromosome-organising complex, condensin, to the pericentromere. Pericentromeric condensin biases sister kinetochores towards capture by microtubules from opposite poles. Overall, shugoshin integrates a bias to sister kinetochore capture with error correction to enable chromosome biorientation. Our findings uncover the molecular basis of the bias to sister kinetochore capture and expose shugoshin as a pericentromeric hub controlling chromosome biorientation. Overall design: Two experiments: Experiment A: Sgo1 is required for condensin localization in the pericentromere. Sample 1: Wild type input DNA Sample 2: Wild type Brn1-6HA ChIP DNA, Sample 3 sgo1D input DNA, Sample 4 sgo1D Brn1-6HA ChIP DNA; Experiment B: Sgo1 is not required for cohesin localization in the periecentromere: Sample 5: wild type input DNA, Sample 6 Wild type Scc1-6HA ChIP DNA, Sample 7, sgo1D input DNA, Sample 8 sgo1D Scc1-6HA ChIP DNA. 1 replicate of each repeat