Negative regulation of mitosis by wee1+, a gene encoding a protein kinase homolog

Cell. 1987 May 22;49(4):559-67. doi: 10.1016/0092-8674(87)90458-2.


Fission yeast wee1- mutants initiate mitosis at half the cell size of wild type. The wee1+ activity is required to prevent lethal premature mitosis in cells that overproduce the mitotic inducer cdc25+. This lethal phenotype was used to clone wee1+ by complementation. When wee1+ expression is increased, mitosis is delayed until cells grow to a larger size. Thus wee1+ functions as a dose-dependent inhibitor of mitosis, the first such element to be specifically identified and cloned. The carboxy-terminal region of the predicted 112 kd wee1+ protein contains protein kinase consensus sequences, suggesting that negative regulation of mitosis involves protein phosphorylation. Genetic evidence indicates that wee1+ and cdc25+ compete in a control system regulating the cdc2+ protein kinase, which is required for mitotic initiation.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA Restriction Enzymes
  • Genes*
  • Genes, Fungal*
  • Genes, Lethal
  • Genes, Regulator*
  • Mitosis
  • Protein Kinases / genetics*
  • Saccharomycetales / genetics*
  • Schizosaccharomyces / enzymology
  • Schizosaccharomyces / genetics*
  • Sequence Homology, Nucleic Acid


  • Protein Kinases
  • DNA Restriction Enzymes

Associated data

  • GENBANK/M16508