Figure 4.

The oxa1ΔC Δguf1 double mutant effectively synthesizes mitochondrial proteins in the presence of tellurite, whereas double mutants overexpressing hGUF1 and hGUF1^A609S are highly and moderately sensitive to this oxidizing compound, respectively. The strains described in Figure 3 were incubated with cycloheximide to block cytosolic translation, and mitochondria were isolated, incubated in the presence of ATP, amino acids and radiolabeled [³⁵S]-methionine before visualization of newly synthesized translation products by autoradiography. Visualized bands are annotated on the left, while molecular weight markers are indicated on the right (a). The rate of mitochondrial translation is quantified in panel (b).