TABLE 2

IME2-lacZ expression in cells carrying PACII-IME1

IME2-lacZ expression
StrainRME1Pact1-IME1MitosisSPOSPO + HU
TLY78+0.020.050.02
TLY770.04670.3
TLY78++427019
TLY77+3928633

All strains carry the reporter plasmid pKB852 (PIME2-CYC1-lacZ-URA3) and the indicated strains carry pTL5 (PACT1-IME1-TRP1), which can complement the sporulation defect of an ime1Δ/ime1Δ diploid. Cells were grown for 2 days in selective media containing 0.5% glucose. Mitotic cultures were collected at this time, and the remaining culture shifted to SPO. After 1 hr in SPO, the culture was divided and one-half was brought to 40 mM HU, while the other remained untreated. These samples were cultured an additional 23 hr and then collected. The β-galactosidase activity (Miller units) of three independent cultures were all within 22% of the presented average value.