A Bir1-Sli15 complex connects centromeres to microtubules and is required to sense kinetochore tension

Cell. 2006 Dec 15;127(6):1179-91. doi: 10.1016/j.cell.2006.09.049.


Proper connections between centromeres and spindle microtubules are of critical importance in ensuring accurate segregation of the genome during cell division. Using an in vitro approach based on the sequence-specific budding yeast centromere, we identified a complex of the chromosomal passenger proteins Bir1 and Sli15 (Survivin and INCENP) that links centromeres to microtubules. This linkage does not require Ipl1/Aurora B kinase, whose targeting and activation are controlled by Bir1 and Sli15. Ipl1 is the tension-dependent regulator of centromere-microtubule interactions that ensures chromosome biorientation on the spindle. Elimination of the linkage between centromeres and microtubules mediated by Bir1-Sli15 phenocopies mutations that selectively cripple Ipl1 kinase activation. These findings lead us to propose that the Bir1-Sli15-mediated linkage, which bridges centromeres and microtubules and includes the Aurora kinase-activating domain of INCENP family proteins, is the tension sensor that relays the mechanical state of centromere-microtubule attachments into local control of Ipl1 kinase activity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aurora Kinases
  • Cell Cycle
  • Centromere / metabolism*
  • Chromosomes, Fungal / metabolism
  • DNA, Fungal / metabolism
  • DNA-Binding Proteins / metabolism
  • Fungal Proteins / genetics
  • Fungal Proteins / isolation & purification
  • Fungal Proteins / metabolism*
  • Kinetochores / metabolism*
  • Microtubule-Associated Proteins / metabolism*
  • Microtubules / metabolism*
  • Mitosis
  • Protein Structure, Tertiary
  • Protein-Serine-Threonine Kinases / metabolism
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Spindle Apparatus / metabolism*


  • CBF3b protein, S cerevisiae
  • DNA, Fungal
  • DNA-Binding Proteins
  • Fungal Proteins
  • Microtubule-Associated Proteins
  • Saccharomyces cerevisiae Proteins
  • Sli15 protein, S cerevisiae
  • Aurora Kinases
  • Protein-Serine-Threonine Kinases