RNR3-lacZ induction is attenuated in wtm2 deletion mutants. Cells lacking WTM1, WTM2, or both genes were grown to midlog phase in YPD medium, incubated with or without 100 mm HU for 3 hr, and then assayed for β-galactosidase activity. Values indicate mean and standard deviation of four independent isolates: P = 0.001 and P = 0.002 for effects of wtm2Δ and wtmΔ12 vs. control on HU induction, respectively. Strains used: TSR30-15, TSG10, TSG12, TSR1257, and TSG1.