Solubilized mitochondria from MITRAC15FLAG- or TIM21FLAG-expressing cells were subjected to anti-FLAG immunoisolation and analyzed by 2D-BN/SDS-PAGE and western blotting. MITRAC15FLAG isolation: Total 0.1 %, Eluate 100 %. TIM21FLAG isolation: Total 0.2 %, Eluate 66 % (TIM21FLAG decoration), 33 % (MITRAC15, ACAD9, MITRAC12, COX1 decoration). 