Specific targeting of ISP6 to mitochondria is mediated by sequences other than its amino terminus.
Most proteins synthesized in cytoplasm target to mitochondria through sequences at their amino termini. However, a previous study suggests that the native carboxyl terminus of ISP6 might be critical of its specific delivery. Here we investigated the sequence directing ISP6 to yeast mitochondrial outer membrane. Unlike mitochondrial presequences, a region at the amino terminus of ISP6 is dispensable for importing the rest of the protein. The carboxyl-terminal end and the nearby transmembrane region of ISP6 are essential to direct the protein exclusively to its correct membrane destination. ISP6 thus may be directed to mitochondria by an unusual sequence.
Cao
W
W
Department of Biochemistry and Biophysics, University of North Carolina Medical School, Chapel Hill 27599-7260, USA.
Douglas
M G
MG
D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D016133:Polymerase Chain Reaction; D011499:Protein Processing, Post-Translational; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins
D017931:DNA Primers; D005656:Fungal Proteins; D008565:Membrane Proteins; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; C082532:TOM6 protein, S cerevisiae