FIGURE 7.

Mitophagy induced by nitrogen starvation or cells grown to stationary phase is defective in taz1Δ yme1Δ yeast. A, an anti-GFP antibody was used to perform Western blotting to ascertain the levels of Om45-GFP and free GFP in the indicated yeast strains before and after nitrogen starvation. Western blotting indicated lower levels of free GFP in taz1Δ yme1Δ cells when compared with wild type and single mutants, indicating inefficient mitophagy in these cells. An antibody against Pgk1 was used to assess equal protein loading among the different lanes. B, yeast strains with a chromosomally tagged Om45-GFP allele were grown to post-log phase for 3–5 days and processed for Western blotting with an anti-GFP antibody to determine the levels of Om45-GFP and free GFP at mid-log and stationary phase. Western blotting indicated a marked reduction in the levels of free GFP in taz1Δ yme1Δ cells when compared with wild type and single mutants, indicating a severe mitophagy defect in these cells. An antibody against Pgk1 was used to assess equal protein loading among the different lanes.