Figure 6.

Synthesis and Turnover of COX Subunits in Control and Subject Fibroblasts

(A) Pulse labeling with [³⁵S] methionine and [³⁵S] cysteine of mitochondrial polypeptides and a 10 min chase (PULSE), as well as the time course of degradation via chases for 8, 17, and 32 hr (CHASE) are shown in control and subject fibroblasts. The seven subunits of complex I (ND), one subunit of complex III (cyt b), three subunits of complex IV (COX), and two subunits of complex V (ATP) are indicated at the left of the figure.

(B) Histograms in which the level of the three COX subunits is normalized to the level of ATP6 in the PULSE and CHASE experiments in (A).