Mitochondria-Associated Degradation Pathway (MAD) Function beyond the Outer Membrane

A discrete pathway for the transfer of intermembrane space proteins across the outer membrane of mitochondria

Mitochondrial proteins are synthesized on cytosolic ribosomes and imported into mitochondria with the help of protein translocases. For the majority of precursor proteins, the role of the translocase of the outer membrane (TOM) and mechanisms of their transport across the outer mitochondrial membrane are well recognized. However, little is known about the mode of membrane translocation for prot...

The Preprotein Translocation Channel of the Outer Membrane of Mitochondria

The protein translocase of the outer mitochondrial membrane (TOM) serves as the main entry site for virtually all mitochondrial proteins. Like many other protein translocases it also has an ion channel activity that can be used to study the dynamical properties of this supramolecular complex. We have purified TOM core complex and Tom40, the main pore forming subunit, from mitochondria of the fi...

Golgi membrane-associated degradation pathway in yeast and mammals.

Autophagy is a cellular process that degrades subcellular constituents, and is conserved from yeast to mammals. Although autophagy is believed to be essential for living cells, cells lacking Atg5 or Atg7 are healthy, suggesting that a non-canonical degradation pathway exists to compensate for the lack of autophagy. In this study, we show that the budding yeast Saccharomyces cerevisiae, which la...

Membrane proteins in the outer mebrane of plastids and mitochondria

An Electron-transport System Associated with the Outer Membrane of Liver Mitochondria

Preparations of rat-liver mitochondria catalyze the oxidation of exogenous NADH by added cytochrome c or ferricyanide by a reaction that is insensitive to the respiratory chain inhibitors, antimycin A, amytal, and rotenone, and is not coupled to phosphorylation. Experiments with tritiated NADH are described which demonstrate that this "external" pathway of NADH oxidation resembles stereochemica...