Distinct nuclear and spindle pole body population of cyclin-cdc2 in fission yeast

Nature. 1990 Oct 18;347(6294):680-2. doi: 10.1038/347680a0.


Cyclins, as subunits of the protein kinase encoded by the cdc2 gene are major controlling elements of the eukaryotic cell cycle. The fission yeast Schizosaccharomyces pombe has a B-type cyclin, which is a nuclear protein encoded by the cdc13 gene. Here we demonstrate the presence of two spatially distinct cdc13 cyclin populations in the nucleus of S. pombe, one of which is associated with the mitotic spindle poles. Both populations colocalize with the product of the cdc2 gene (p34cdc2). Treatment of cells with the antimicrotubule drug thiabendazole prevents cyclin degradation and blocks the tyrosine dephosphorylation and activation of cdc2. These results suggest a key regulatory role of the cdc2-cyclin complex in the initiation of mitotic spindle formation and also that mitotic microtubule function is required for cdc2 activation.

Publication types

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

MeSH terms

  • CDC2 Protein Kinase / antagonists & inhibitors
  • CDC2 Protein Kinase / metabolism*
  • Cell Nucleus / metabolism*
  • Cyclins / metabolism*
  • Fluorescent Antibody Technique
  • Fungal Proteins / metabolism
  • Mitosis
  • Phosphotyrosine
  • Schizosaccharomyces / drug effects
  • Schizosaccharomyces / metabolism
  • Schizosaccharomyces / ultrastructure*
  • Spindle Apparatus / metabolism*
  • Thiabendazole / pharmacology
  • Tyrosine / analogs & derivatives
  • Tyrosine / metabolism


  • Cyclins
  • Fungal Proteins
  • Phosphotyrosine
  • Tyrosine
  • CDC2 Protein Kinase
  • Thiabendazole