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Evidence that the yeast spindle assembly checkpoint has a target other than the anaphase promoting complex

Catherine A Andrews1, Laura A Díaz-Martínez, Juan F Giménez-Abián

  • 1Department of Genetics, Cell Biology & Development, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.

Cell Cycle (Georgetown, Tex.)
|November 1, 2005
PubMed

Insights

The spindle assembly checkpoint delays cell division by inhibiting the Anaphase Promoting Complex (APC). Even without APC, yeast cells activate this checkpoint, indicating a non-APC target controls cell cycle progression.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • The spindle assembly checkpoint (SAC) is crucial for accurate chromosome segregation during cell division.
  • SAC prevents anaphase onset by inhibiting the Anaphase Promoting Complex (APC), a key regulator of cell cycle progression.
  • APC's specificity factor, Cdc20, is a known target of SAC.

Purpose of the Study:

  • To investigate if the Anaphase Promoting Complex (APC) is the sole target of the spindle assembly checkpoint (SAC).
  • To determine if cells lacking APC and its targets exhibit functional SAC.
  • To identify potential non-APC targets of the SAC.

Main Methods:

  • Utilized APC-null yeast cells to assess SAC functionality.
  • Observed cell cycle progression in G2/M phase.
  • Analyzed the role of APC-Cdc20 in SAC-mediated cell cycle arrest.

Main Results:

  • APC-null yeast cells demonstrated the ability to activate the spindle assembly checkpoint.
  • Cell cycle progression was delayed in G2/M phase in these cells.
  • These findings challenge the notion that APC-Cdc20 is the sole target of the SAC.

Conclusions:

  • The spindle assembly checkpoint possesses a non-APC target that can inhibit anaphase onset.
  • The SAC's regulatory mechanism is more complex than previously understood.
  • Further research is needed to identify the novel non-APC target(s) of the SAC.

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