(A) Excerpts of complexome profiling data showing the distribution of CIV subunits and assembly factors HIGD1A, HIGD2A, CMC1 and COA3 in control (143B), COX1∆ and COX2∆ cybrids. The relative abundance and distribution of detected proteins is shown in the lower graphs. The localization of SC I+III2plus in COX2Δ cybrids is highlighted with a red line. The approximate molecular weights of CIV-containing structures are indicated on the top (in kDa). 