Mitochondrial targeting sequences
Mitochondrial targeting sequences (MTS) function in targeting and import of nuclear encoded proteins to the mitochondria. Unlike the ER signal sequences, the length of MTS greatly varies between 15-150. Although it has been thought that mitochondrial proteins are targeted posttranslationally (after complete synthesis of proteins), recent studies show that mitochondrial inner membrane proteins which contain hydrophobic transmembrane domains are cotranslationally targeted, and via the ER membrane. How diverse types of MTS direct proteins to mitochondria and what sequence characteristics in MTS and mature domain region contribute in proper targeting in vivo largely remain unknown, and we aim to answer to these questions.