FIGURE 4:

Tim22 import is defective in the mia40-F311E mitochondria. (A–D) Radiolabeled precursors of Su9-DHFR, Tim9, and Tim22 were incubated with mitochondria isolated from WT and mia40-F311E mutant strains grown at 19°C. (A–C) Mitochondria were treated with proteinase K, except the Tim9 samples 1–8. (D) Mitochondria were solubilized in digitonin-containing buffer and analyzed by blue native electrophoresis. (E) Wild-type (MIA40) strain and mia40-F311E mutant transformed with the multicopy ERV1 plasmid were subjected to consecutive 10-fold dilutions, spotted on YPD and YPG, and grown for 2 d at 37°C. (F) Mitochondria were isolated from mia40-F311E– and mia40-F311E–overproducing Erv1 strain grown at 19°C and analyzed by Western blotting. (G) Radiolabeled Tim22 precursor was incubated with mitochondria isolated from the indicated strains. Mitochondria were treated with proteinase K. WT, wild type. Asterisk indicates a nonspecific band.