Pulse-chase [35S]methionine radiolabeling of mitochondrial translation products in wild type and MITRAC15-/- cells. Samples were analyzed by SDS-PAGE and digital autoradiography. Signal intensity of ND2 was normalized to the ATP6 signal and the relative ND2 stability was calculated by relative chase ND2 signal/relative pulse ND2 signal (error bars indicate SEM from three biological replicates; *p < 0,05; unpaired t-test). 