Figure 4

The TRKO mutants are deficient in respiratory functions. A. respiration; B. ETC CI activity; C. ETC CIV activity, and D. ROS production.dpb 4∆, hfl1∆, and rbf1∆ each respired less (2.2-5-fold reduction) than WT cells. CI activity decreased in each mutant proportionally to their decrease in respiration. CIV activity was 5.5 fold lower in the TRKO mutants. In D, ROS production compared to WT cells was highest in the rbf1∆, although also significantly increased in hfl1∆. The dpb4∆ produced ROS equal to WT cells. E. ETC CI and CIV inhibitors: growth of mutants and WT cells on YPD containing either rotenone (C1 inhibitor) or KCN (CIV inhibitor) is shown. rbf1∆ and hfl1∆ are hypersensitive to both inhibitors while dpb4∆ was less so.