We analyzed the submitochondrial location and biogenesis pathway of the phosphate carrier (P(i)C), also termed p32, of Saccharomyces cerevisiae mitochondria. P(i)C/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 P(i)C/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 P(i)C/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 P(i)C/p32 with MOM72 being responsible for the bulk of import. Yeast P(i)C/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.
|Number of pages||7|
|Journal||Journal of Biological Chemistry|
|Publication status||Published - Jan 1 1993|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology