A conserved proline residue is present in the transmembrane-spanning domain of Tom7 and other tail-anchored protein subunits of the TOM translocase.
The TOM translocase consists of several integral membrane proteins organised around the channel forming protein Tom40. Here we show that one of these protein subunits, Tom7, is a tail-anchored protein. The carboxy-terminal 33 amino acids of Tom7 contain the information for targeting the protein to the mitochondrial outer membrane, and a conserved proline residue within the transmembrane segment is required for efficient targeting of Tom7 to the outer membrane. An equivalent proline residue is important in targeting each of the other three tail-anchored proteins that associate with Tom40 to form the core of the TOM translocase.
Allen
Renae
R
Russell Grimwade School of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3010, Australia.
Egan
Billie
B
Gabriel
Kipros
K
Beilharz
Traude
T
Lithgow
Trevor
T
D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D007425:Intracellular Membranes / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics; D046911:Macromolecular Substances; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D008969:Molecular Sequence Data; D011392:Proline / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D005656:Fungal Proteins; D008164:Luminescent Proteins; D046911:Macromolecular Substances; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; C099634:TOM7 protein, S cerevisiae; C066555:Tom40 protein, S cerevisiae; D049452:Green Fluorescent Proteins; D011392:Proline