Figure 8.

Assembly of Tom5, Tom6, and Tom7 is dependent on Sam37. (A) ³⁵S-labeled Tom5 (lanes 1–6), Tom6 (lanes 7–12), and Tom7 (lanes 13–18) precursors were imported into isolated mitochondria from wild-type (WT) and sam37Δ yeast cells for the indicated times. Reisolated mitochondria were lysed in digitonin-containing buffer and separated by blue native electrophoresis, and radiolabeled proteins were detected by digital autoradiography. (B) ³⁵S-labeled Tom5 (lanes 1–6), Tom6 (lanes 7–12), and Tom7 (lanes 13–18) precursors were imported into isolated mitochondria from wild-type and sam37Δ yeast cells for the indicated times. The reisolated mitochondria were resuspended in 0.1 M Na₂CO₃, pH 11.5, and incubated on ice for 30 min. Membrane sheets were isolated by ultracentrifugation, solubilized in laemmli buffer, and separated by Tris-tricine gel electrophoresis. (C) Growth of wild-type yeast, mdm10Δ, and mdm10Δ sam37Δ deletion strains on YPD at 24, 30, and 37°C. (D) 50 μg mitochondria from wild-type, mdm10Δ, and mdm10Δ sam37Δ yeast cells were solubilized in digitonin-containing buffer, separated by blue native electrophoresis, and subsequently analyzed by immunoblotting with antibodies directed against Tom5. Arrowheads indicate intermediate complexes.