The protein kinase Kin4 inhibits exit from mitosis in response to spindle position defects

Mol Cell. 2005 Jul 22;19(2):223-34. doi: 10.1016/j.molcel.2005.06.005.


Accurate nuclear position is essential for each daughter cell to receive one DNA complement. In budding yeast, a surveillance mechanism known as the spindle position checkpoint ensures that exit from mitosis only occurs when the anaphase nucleus is positioned along the mother-bud axis. We identified the protein kinase Kin4 as a component of the spindle position checkpoint. KIN4 prevents exit from mitosis in cells with mispositioned nuclei by inhibiting the mitotic exit network (MEN), a GTPase signaling cascade that promotes exit from mitosis. Kin4 is active in cells with mispositioned nuclei and predominantly localizes to mother cells, where it is ideally situated to inhibit MEN signaling at spindle pole bodies (SPBs) when anaphase spindle elongation occurs within the mother cell.

Publication types

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

MeSH terms

  • Anaphase / physiology
  • Cell Cycle Proteins / metabolism
  • Cytoskeletal Proteins / metabolism
  • Mitosis / drug effects*
  • Mitosis / genetics
  • Mitosis / physiology
  • Protein Kinases / genetics
  • Protein Kinases / metabolism
  • Protein Kinases / physiology*
  • Protein Tyrosine Phosphatases / metabolism
  • Protein-Serine-Threonine Kinases
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Saccharomyces cerevisiae Proteins / physiology*
  • Spindle Apparatus / drug effects*
  • Spindle Apparatus / metabolism*
  • Time Factors


  • BFA1 protein, S cerevisiae
  • BUB2 protein, S cerevisiae
  • CDC14 protein, S cerevisiae
  • Cell Cycle Proteins
  • Cytoskeletal Proteins
  • Saccharomyces cerevisiae Proteins
  • Protein Kinases
  • KIN4 kinase, S cerevisiae
  • Protein-Serine-Threonine Kinases
  • Protein Tyrosine Phosphatases