Cell growth of <i>MEC1</i>, <i>RAD3</i>, <i>RAD18</i>, <i>yKu70</i>, and mutant cells after HU or MMS treatment.

<p>(A) Under conditions with no genotoxic treatment, the <i>MEC1</i> P2186A/A2351S double mutant showed a lower growth rate compared to WT. (B) Only <i>mec1Δ sml1Δ</i> showed significantly slower growth under HU treatment. (C) Under MMS treatment, all strains showed slower growth compared to WT. <i>mec1Δ sml1Δ</i> showed significantly reduced growth compared to WT-Hyg in both HU and MMS treatment conditions. (D) Under conditions without treatment, significant differences in growth were observed between the <i>RAD3</i> WT and mutant strains. Only the <i>RAD3</i> R594C mutant showed significantly reduced growth compared to WT. (E) Under 50 mM HU treatment, <i>RAD3</i> R594C cells showed substantially reduced growth compared to WT, WT-Hyg, and other mutant strains. (F) In 0.01% MMS-treated liquid YPD, the <i>RAD3</i> R594C mutant showed substantially reduced growth compared to WT, WT-Hyg, and other mutant strains. (G) Under conditions without treatment, no significant differences in growth were observable in WT and mutant strains. (H) Under HU treatment, <i>RAD18</i> L50R did not show significantly reduced growth compared to WT-Hyg. (I) Under MMS treatment, the <i>RAD18</i> L50R mutant strain did not show any significant difference in growth when compared to WT and WT-Hyg. (J) In YPD plates without genotoxic agents, <i>yKu70</i> R456M showed higher growth rate compared to WT. <i>yKu70</i> E391V displayed considerably reduced growth compared to WT and other mutant strains. (K) No significant growth differences were observed in WT and mutant strains when cultured in YPD containing HU. (L) Under MMS treatment, <i>yKu70</i> E391V showed reduced growth compared to the WT-Hyg and <i>yKu70</i> R456M strains. Cells were grown for 8 h in varying conditions, after which OD₆₀₀ values were measured. Student’s paired <i>t</i>-test was performed on WT, WT-Hyg, and all mutant strains. WT: wild-type; WT-Hyg: wild-type with hygromycin vector. *: P-value < 0.05. **: P-value <0.01. * and ** without comparative bars indicate statistically significant differences compared to WT. X axis indicates mutant strain and Y axis indicates OD₆₀₀ value.