Structural basis of membrane protein chaperoning through the mitochondrial intermembrane space
Weinhäupl K, Lindau C, Hessel A, Wang Y, Schütze C, Jores T, Melchionda L, Schönfisch B, Kalbacher H, Bersch B, Rapaport D, Brennich M, Lindorff-Larsen K, Wiedemann N, Schanda P.
The exchange of metabolites between the mitochondrial matrix and the cytosol depends on beta-barrel channels in the outer and alpha-helical carrier proteins in the inner membrane. We reveal the functional principle how the essential TIM chaperones escort these proteins through the intermembrane space. Multiple clamp-like binding sites hold the mitochondrial membrane proteins in a translocation-competent elongated form, thus mimicking characteristics of co-translational membrane insertion.