Figure 2.

Inhibition by KCN of endogenous respiration rate in TD buffer in the presence of DNP (○), or of (ascorbate + 0.2 mM TMPD)-dependent respiration rate in TD buffer in the presence of DNP and antimycin A (•), in intact 143B.TK⁻ cells and transmitochondrial human cell lines carrying mtDNA with the mitochondrial tRNA^Lys gene mutation (pT1, pT4) or wild-type mtDNA (pT3), derived from a patient affected by the MERRF encephalomyopathy (8). The data shown represent the means ± SE obtained in six or seven determinations on 143B cells, three determinations on pT1 cells, and four determinations on pT4 cells (the error bars that fall within the limits of the individual data symbols are not shown), or the results of a single determination on pT3 cells.