Mitotic control mutants have altered sensitivity to increased expression of flp1+. Mitotic control mutants have altered sensitivity to increased expression of flp1+. A single, nmt1-promoter-controlled copy of flp1+ was introduced into the leu1 locus and crossed into the indicated strain backgrounds. Expression of flp1+ was induced and cell number was determined at intervals thereafter. Cells were grown at 25°C. (A) The effect of increased flp1+ expression in wee1-6 and cdc25::ura4+ wee1-50. Induced images were taken 26 hours (approximately 6 generations) after induction. (B) Cell number increase after induction of flp1+. Cell numbers are expressed in arbitrary units. Cell numbers at 16 hours were approximately 106 ml-1. (C,D) Induction of flp1+ in dominant activated alleles of cdc2. Nathalie Cueille et al. J Cell Sci 2001;114:2649-2664 © The Company of Biologists Limited 2001