Figure 3.

Dark respiration in mETC mutants. Dark respiration was determined in leaf strips of fully expanded leaves from 5-week-old plants according to Umbach et al. (2006), using a Clarke-type oxygen electrode. Dark respiration R_d (A) was determined as oxygen consumption over a period of 30 min after 30 min of initial acclimatization. The percentage of alternative respiration (B) was determined by recording KCN-insensitive respiration for additional 30 min after the addition of 100mM KCN, or until steady state was reached. Data are means of four independent biological replicates ± SE. Col-0 (black bars), AOX-OX (dark gray bars), ndufs4 (white bars), sdh2-1 (left hatched bars), ucr8-1 (right hatched bars), ucp1-2 (light gray bars). Significant differences to Col-0 in a pairwise t-test are indicated by asterisks with *: p < 0.05 and **: p < 0.005.