The wee1 protein kinase is required for radiation-induced mitotic delay.
Cellular feedback or 'checkpoint' mechanisms maintain the order of completion of essential, cell-cycle related functions. In the budding yeast, for example, the RAD9 gene product is required to delay progression into mitosis in response to DNA damage. Similarly, in fission yeast, the cdc25 and cdc2 gene products influence the ability of cells to delay mitosis in response to the inhibition of DNA synthesis. Because these two checkpoint controls regulate the same event, mitosis, we observed the effect of gamma-irradiation on cell cycle progression in fission yeast, to test whether the two controls require the same cell-cycle regulatory elements. We show that gamma-radiation-induced mitotic delay requires functional wee1 protein kinase but does not seem to involve the cdc25 pathway. Mitotic delay in response to DNA damage is thus distinct from the delay induced by inhibition of DNA synthesis, which involves cdc25 but is not dependent on wee1.
Rowley
R
R
Department of Radiology, University of Utah Medical Center, Salt Lake City 84132.
Hudson
J
J
Young
P G
PG
D018797:Cell Cycle Proteins; D004260:DNA Repair; D005656:Fungal Proteins / Q000378:metabolism; D005720:Gamma Rays; D008938:Mitosis / Q000528:radiation effects; D009687:Nuclear Proteins; D011494:Protein Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases; D012568:Schizosaccharomyces / Q000166:cytology* / Q000201:enzymology / Q000528:radiation effects; D029702:Schizosaccharomyces pombe Proteins
D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D009687:Nuclear Proteins; D029702:Schizosaccharomyces pombe Proteins; D011494:Protein Kinases; C068689:wee1 protein, S pombe; D011505:Protein-Tyrosine Kinases