Figure 8.

Cells with the cit1 deletion exhibit increased sensitivity to ROS-generating chemicals. (A) Effect of CIT1-deletion on the survival of yeast cells in the presence of ROS-generating chemicals. Yeast cells (wild type, Δcit1, Δcit2, and Δcit1Δcit2) grown in SCD were exposed to 100 μM antimycin, 100 μM rotenone, 10 mM H₂O₂, or 20 mM acetic acid for 1 h in the presence or absence of 10 mM Tiron. Surviving cells were evaluated by CFU assays carried out in triplicate. (B) Effect of CIT1-deletion on the intracellular levels of ROS in the presence of ROS-generating chemicals. The yeast strains were prepared and treated with the ROS-generating chemicals as described above. The cells were then stained with DCFH-DA and examined by fluorescence microscopy. The numbers of DCFH-DA–positive cells were estimated in fluorescence images and total cells in corresponding DIC images.