title: In vivo protein-interaction mapping of a mitochondrial translocator protein Tom22 at work.
abstract: Mitochondrial protein import requires cooperation of the machineries called translocators in the outer and inner mitochondrial membranes. Here we analyze the interactions of Tom22, a multifunctional subunit of the outer membrane translocator TOM40 complex, with other translocator subunits such as Tom20, Tom40, and Tim50 and with substrate precursor proteins at a spatial resolution of the amino acid residue by in vivo and in organello site-specific photocross-linking. Changes in cross-linking patterns caused by excess substrate precursor proteins or presequence peptides indicate how the cytosolic receptor domain of Tom22 accepts substrate proteins and how the intermembrane space domain of Tom22 transfers them to Tim50 of the inner-membrane translocator.
authors: Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
authors: Takuya
authors: T
authors: Shiota
authors: Hide
authors: H
authors: Mabuchi
authors: Sachiko
authors: S
authors: Tanaka-Yamano
authors: Koji
authors: K
authors: Yamano
authors: Toshiya
authors: T
authors: Endo
mesh_terms: D000595:Amino Acid Sequence; D003432:Cross-Linking Reagents / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D033681:Mitochondrial Membrane Transport Proteins / Q000737:chemistry / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism; D011485:Protein Binding; D025941:Protein Interaction Mapping; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D003432:Cross-Linking Reagents; D033681:Mitochondrial Membrane Transport Proteins; D024101:Mitochondrial Proteins; D010455:Peptides; D029701:Saccharomyces cerevisiae Proteins; C090857:TOM22 protein, S cerevisiae