Retro-translocation of mitochondrial intermembrane space proteins

08.06.2015

Bragoszewski P, Wasilewski M, Sakowska P, Gornicka A, Böttinger L, Qiu J, Wiedemann N, Chacinska A.

Proc Natl Acad Sci U S A. 2015;112(25):7713-8.

Proc Natl Acad Sci U S A.            online article

The mitochondrial proteome is maintained by import of mitochondrial precursor proteins. Whether the reverse movement of unfolded proteins to the cytosol occurs across the intact outer membrane is unknown. We found that reduced, conformationally destabilized proteins are released from mitochondria. We identified Tom40 as an escape gate. We propose that the mitochondrial proteome is not only regulated by the import and degradation of proteins but also by their retro-translocation to the cytosol.