title: Mitochondria-targeting sequence, a multi-role sorting sequence recognized at all steps of protein import into mitochondria.
abstract: The intracellular sorting of newly synthesized precursor proteins (preproteins) to mitochondria depends on the "mitochondria-targeting sequence" (MTS), which is located at the amino termini of the preproteins. MTS is required, however, not only for targeting newly synthesized preproteins to mitochondria, but also for all the following steps along the mitochondrial protein import pathway. MTS of nascent preproteins is first recognized by a cytoplasmic molecular chaperone, MSF, and then by Tom70 and Tom20 of the mitochondrial outer membrane receptor complex, Tom5 and Tom40 of the outer membrane protein translocation machinery, Tim23 of the inner membrane protein translocation machinery, and finally the processing peptidase, MPP, in the matrix. MTS is a multi-role sorting sequence which specifically interacts with various components along the mitochondrial protein import pathway. Recognition of MTS at multiple steps during the import of preproteins may contribute to the strict sorting of proteins destined for mitochondria.
authors.affiliation: Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka, Fukuoka, 812-8582, Japan. omurat@mxs.meshnet.or.jp
authors.forename: T
authors.initials: T
authors.lastname: Omura
mesh_terms: D048948:14-3-3 Proteins; D000595:Amino Acid Sequence; D000818:Animals; D001692:Biological Transport / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D029701:Saccharomyces cerevisiae Proteins; D017421:Sequence Analysis; D000099221:Protein Kinase C zeta
chemical_list: D048948:14-3-3 Proteins; D002352:Carrier Proteins; D005656:Fungal Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D018832:Molecular Chaperones; D011506:Proteins; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D029701:Saccharomyces cerevisiae Proteins; C490392:Prkcz protein, rat; D000099221:Protein Kinase C zeta; C489350:TOM20 protein, S cerevisiae; C106794:TOM5 protein, S cerevisiae; C489039:TOM70 protein, S cerevisiae; C084008:TOMM20 protein, human; C066555:Tom40 protein, S cerevisiae; C489998:Tomm20 protein, rat; C490391:Ywhaz protein, rat; C090759:mitochondrial import stimulation factor, rat