Dietmeier K, Zara V, Palmisano A, Palmieri F, Voos W, Schlossmann J, Moczko M, Kispal G, Pfanner N
Biochemisches Institut, Universität Freiburg, Germany.
J Biol Chem. 1993 Dec 5;268(34):25958-64.
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.
我们分析了酿酒酵母线粒体中磷酸盐载体（PiC，也称为p32）的亚线粒体定位和生物合成途径，发现PiC/p32表现为一种整合膜蛋白，与内膜的ADP/ATP载体共分离。PiC/p32前体的导入需要内膜两侧的膜电位，这支持了其定位于内膜。这使得PiC/p32的主要功能不太可能是线粒体外膜表面的导入受体。此外，我们发现受体MOM72和MOM19都参与了PiC/p32前体的导入途径，其中MOM72负责大部分的导入。因此，酵母PiC/p32不仅在结构上与ADP/ATP载体同源，而且具有相似的靶向机制和亚线粒体定位，支持将其归类为内膜载体家族的成员。
