Viability assays.

<p>All the mutants were derived from the TG81 <i>tlc1</i>Δ type II survivors (TG81 for short), and TG300 <i>tlc1</i>Δ type II survivors (TG300 for short) served as a control. (A) Dotting assay. Cell cultures were diluted with sterile water to a concentration of OD₆₀₀ ∼0.3, and 3 µl of each 5-fold serial dilutions was dotted on YC plates. Plates were incubated at 30°C for 2 to 3 days and then photographed. <i>rad50</i>Δ and <i>cgi121</i>Δ are mutants of slow growth, which were dotted earlier than other strains. (B) Quantification of viability assays. 100 µl of the 5^th dilution sample in (A) was plated. Plates were incubated at 30°C for 2 to 3 days and colony numbers were counted. The viability was calculated using the formula: Viability = (Induced total - Induced uncut)/Uninduced total. Error bars represent standard deviations of three independent experiments. Compared to TG81 control, P values of the <i>rad50</i>Δ, <i>rad59Δ</i>, <i>cgi121</i>Δ, <i>tel1Δ</i> and <i>chk1Δ</i> mutants are 0.030, 0.025, 0.015, 0.295 and 0.317, respectively. Significance (*) is defined by P value <0.05.