Targeting and translocation of the phosphate carrier/p32 to the inner membrane of yeast mitochondria

J Biol Chem. 1993 Dec 5;268(34):25958-64.

Abstract

We analyzed the submitochondrial location and biogenesis pathway of the phosphate carrier (PiC), also termed p32, of Saccharomyces cerevisiae mitochondria, PiC/p32 was found to behave as an integral membrane protein that cofractionated with the ADP/ATP carrier of the inner membrane. Import of the precursor of PiC/p32 required a membrane potential across the inner membrane, supporting its localization to the inner membrane. This makes it unlikely that the major function of PiC/p32 is that of an import receptor on the surface of the mitochondrial outer membrane. Furthermore, we found that both receptors MOM72 and MOM19 were involved in the import pathway of the precursor of PiC/p32 with MOM72 being responsible for the bulk of import. Yeast PiC/p32 is thus not only structurally homologous to the ADP/ATP carrier, but has a similar targeting mechanism and submitochondrial location, supporting its classification as a member of the inner membrane carrier family.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal
  • Antimycin A / pharmacology
  • Base Sequence
  • Carrier Proteins / isolation & purification
  • Carrier Proteins / metabolism*
  • Cloning, Molecular
  • Escherichia coli
  • Fungal Proteins*
  • Genotype
  • Immunoblotting
  • Intracellular Membranes / drug effects
  • Intracellular Membranes / metabolism*
  • Kinetics
  • Membrane Proteins / isolation & purification
  • Membrane Proteins / metabolism
  • Mitochondria / drug effects
  • Mitochondria / metabolism*
  • Mitochondrial Membrane Transport Proteins
  • Mitochondrial Precursor Protein Import Complex Proteins
  • Molecular Sequence Data
  • Neurospora crassa / metabolism*
  • Oligomycins / pharmacology
  • Phosphate-Binding Proteins
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Valinomycin / pharmacology

Substances

  • Antibodies, Monoclonal
  • Carrier Proteins
  • Fungal Proteins
  • Membrane Proteins
  • Mitochondrial Membrane Transport Proteins
  • Mitochondrial Precursor Protein Import Complex Proteins
  • Oligomycins
  • Phosphate-Binding Proteins
  • Receptors, Cytoplasmic and Nuclear
  • Recombinant Proteins
  • Saccharomyces cerevisiae Proteins
  • TOM20 protein, S cerevisiae
  • TOM70 protein, S cerevisiae
  • Valinomycin
  • Antimycin A