Cell-Cycle Experiments Multiple independent colonies from each strain were grown at 30uC overnight in YEP-raffinose liquid medium. Yeast cells were diluted to YEP-raffinose liquid medium to OD595 0.1 to refresh for three hours, incubated at 30uC for additional four hours in 100 mM a-factor or 20 mg/ml nocodazole. Cultures were split and half continued to grow in YEP-raffinose with a-factor or nocodazole while the other half received galactose to a final concentration of 2% for one hour. Yeast cells from YEP-raffinose and YPGal were then serial diluted on YPD and YPGal plates, respectively. The frequency of imprecise end joining was determined as the ratio of the number of colonies growing on YPGal vs. YPD from per ml of culture. Supporting Information Figure S1 Southern blot analysis of 5-FOA-resistant survivors after HO endonuclease induced. Found at: doi:10.1371/journal.pgen.1000060.s001 (0.55 MB DOC) References 1. 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