Mitochondrial ATP-independent chaperones.

Mitochondria possess a dedicated-chaperone system in the intermembrane space, the small Tims that are ubiquitous in all eukaryotes from yeast to man. They escort membrane proteins to the outer or the inner membrane for proper insertion. These mitochondrial chaperones do not require external energy to perform their function and have structural similarities to other ATP-independent chaperones. Here, we discuss their structural properties and how these relate to their chaperoning function in the mitochondrial intermembrane space.