After C12orf62 down regulation, [35S]methionine labelling was performed. During labeling mitochondrial translation was inhibited with puromycin (pur) (2 µg/ml). MITRAC15FLAG interacting nascent chains were isolated by FLAG-immunoprecipitation from cell lysates. Eluates were subjected to SDS-PAGE, analyzed by digital autoradiography. Total 2 %, MITRAC15FLAG eluates 100 % (in case of C12ORF62FLAG, 25% of eluate was loaded as a standard). Red asterisks, accumulating nascent chains of ND2. The accumulating nascent chains of ND2 of lane 12 is presented in a magnification. F1-F3 mark nascent chains of COX1 [18]. 