Sds22 regulates aurora B activity and microtubule-kinetochore interactions at mitosis

J Cell Biol. 2010 Oct 4;191(1):61-74. doi: 10.1083/jcb.200912046.

Abstract

We have studied Sds22, a conserved regulator of protein phosphatase 1 (PP1) activity, and determined its role in modulating the activity of aurora B kinase and kinetochore-microtubule interactions. Sds22 is required for proper progression through mitosis and localization of PP1 to mitotic kinetochores. Depletion of Sds22 increases aurora B T-loop phosphorylation and the rate of recovery from monastrol arrest. Phospho-aurora B accumulates at kinetochores in Sds22-depleted cells juxtaposed to critical kinetochore substrates. Sds22 modulates sister kinetochore distance and the interaction between Hec1 and the microtubule lattice and, thus, the activation of the spindle assembly checkpoint. These results demonstrate that Sds22 specifically defines PP1 function and localization in mitosis. Sds22 regulates PP1 targeting to the kinetochore, accumulation of phospho-aurora B, and force generation at the kinetochore-microtubule interface.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aurora Kinase B
  • Aurora Kinases
  • Chromosome Segregation
  • HeLa Cells
  • Humans
  • Kinetochores / metabolism*
  • Microtubules / metabolism*
  • Mitosis*
  • Phosphorylation
  • Protein Phosphatase 1 / genetics
  • Protein Phosphatase 1 / metabolism
  • Protein Phosphatase 1 / physiology*
  • Protein Serine-Threonine Kinases / metabolism*
  • Protein Transport

Substances

  • PPP1R7 protein, human
  • AURKB protein, human
  • Aurora Kinase B
  • Aurora Kinases
  • Protein Serine-Threonine Kinases
  • Protein Phosphatase 1