(D) Mean incorporation rates of CIII subunits CORE2 and RISP into SC I+III2+IV1 from control cells and into SCs I+III2 from CIV-KO cybrids. Signals from at least three independent experiments were quantified and normalized by CII subunit SDHA levels. Time-point values are expressed as percentages of untreated cells (SS) and indicated as mean±SD. 