Figure 6.

Mitochondrial Activity Is Altered by SRV2 Deletion

(A) High-resolution respirometry was used to assay the oxygen consumption rate (OCR) as described in Methods. OCRs of wild-type, Δsrv2, srv2-189, and Δdnm1 yeast in YPD with mitochondrial respiration complex inhibitors were determined (Figure S6). Reserve capacities (1-Routine respiration/maximal respiration) of wild-type, Δsrv2, srv2-189, and Δdnm1 mitochondria were 32.54%, 21.22%, 18.62%, and 30.17%, respectively. **p < 0.01 vs. WT cells.

(B) OCRs for wild-type, Δsrv2, srv2-189, and Δdnm1 cells were determined in YPD/YPR. Increases of OCR (from YPD to YPR) in wild-type, Δsrv2, srv2-189, and Δdnm1 cells were 2.34-, 1.53-, 1.47-, and 1.79-fold, respectively. ***p < 0.001 vs. WT cells. (C) Mitochondrial membrane potential of wild-type, ∆srv2, srv2-189, and ∆dnm1 yeast in YPD/YPR medium was evaluated by DiOC₆ staining followed by flow cytometry. Wild-type (WT) and ∆dnm1 yeast cells showed higher mitochondria membrane potentials in YPR medium, but ∆srv2 and srv2-189 yeast cells did not. Increases of DiOC₆ intensity (YPD vs. YPR) in WT, ∆srv2, srv2-189, and ∆dnm1 were 3.94-, 0.90-, 0.93-, and 3.34-fold, respectively. **p < 0.01 vs. WT cells. Mean values ± SE were obtained by averaging the values of three independent experiments.