Influence of <i>DUN1</i>, <i>SML1</i>, or <i>CRT1</i> deletion on the sensitivity of <i>tsa1</i>Δ cells to DNA damage and replicative stress.

<p>(A) Spot tests. Ten-fold serial dilutions of strains BY4741 (<i>WT</i>), <i>dun1</i>Δ, <i>sml1</i>Δ, <i>crt1</i>Δ, <i>tsa1</i>Δ, <i>tsa1</i>Δ <i>dun1</i>Δ, <i>tsa1</i>Δ <i>sml1</i>Δ, and <i>tsa1</i>Δ <i>crt1</i>Δ were spotted on YPD medium containing indicated doses of H₂O₂, HU or 4-NQO. Cells were exposed to the indicated dose of UV after plating. Plates were incubated for 4 days at 30°C. Experiments were repeated for six times and similar results were obtained. (B) Survival curves. Logarithmically growing yeast cells, BY4741 (<i>WT</i>), <i>dun1</i>Δ, <i>sml1</i>Δ, <i>tsa1</i>Δ, <i>tsa1</i>Δ <i>dun1</i>Δ, and <i>tsa1</i>Δ <i>sml1</i>Δ, in YPD were treated with indicated doses of 4-NQO for 90 min before plating on YPD agar. For UV treatment, cells were first plated onto YPD agar followed by UV irradiation at the indicated doses. Plates were incubated for 3 days at 30°C, and then counted for survival. The number of colonies from untreated plates was taken as 100%. Experiments were repeated for three times and similar results were obtained. (C) <i>TSA1</i> catalytic cysteine mutant cannot complement the HU sensitivity in <i>tsa1</i>Δ cells. Tenfold serial dilutions of the indicated strains transformed with pRS415, pTSA1, pTSA1C47S, or pTSA1C170S were spotted on SC-Leu plates containing 2% glucose and the indicated doses of diamide or HU. Note that cells grew more slowly on SC plates than on YPD plates as shown in (A). (D) Influence of <i>DUN1</i>, <i>SML1</i>, or <i>CRT1</i> deletion on the sensitivity of <i>sod1</i>Δ cells to DNA damage. (E) Complementation of drug sensitivity in <i>tsa1</i>Δ <i>dun1</i>Δ cells by <i>TSA1</i> or <i>DUN1</i>.