Fig. 2.

Diversity of mechanisms for proteins targeting in mitochondria. (I) Chaperone-mediated post-translational targeting. (II) Co-translational targeting of the complex consisting of mRNA, ribosome and MTS-containing nascent peptide to the TOM/TIM pore, mediated by NAC (Nascent polypeptide-Associated Complex). (III) Direct binding of NAC to proteins of the outer mitochondrial membrane. (IV) Binding of transcripts to the outer mitochondrial membrane through mRNA-binding proteins. (V) ER-SURF pathway: DJP1-mediated insertion of proteins synthesized on the ER membrane into the mitochondrial membrane. Details are in the text.