Transport of proteins across or into the mitochondrial outer membrane.
Mitochondria are surrounded by two biological membranes. The outer mitochondrial membrane contains two major translocators, the TOM40 (TOM) and TOB/SAM complexes for protein translocation across and/or insertion into the outer membrane. The TOM40 complex functions as an entry gate for most mitochondrial proteins, and the TOB/SAM complex as a specialized insertion machinery for beta-barrel membrane proteins. In order to handle loosely folded or unfolded precursor polypeptides, those translocators cooperate with chaperones in the cytosol and intermembrane space, and also exhibit chaperone-like functions on their own. Several alpha-helical membrane proteins take 'non-standard' routes to be inserted into the outer membrane. Here we review the current view on a remarkable variety of mechanisms of protein transport taking place at the mitochondrial outer membrane.
Endo
Toshiya
T
Department of Chemistry, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan. endo@biochem.chem.nagoya-u.ac.jp
Yamano
Koji
K
D000818:Animals; D001419:Bacteria / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D008954:Models, Biological; D010455:Peptides / Q000737:chemistry; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D011506:Proteins / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000378:metabolism
D010455:Peptides; D011506:Proteins