Secondly, in the process of translocation of proteins across the inner membrane of mitochondria Hsp70 binds to polypeptides traversing the membrane facilitating their movement into the mitochondrial matrix. We use tools of biochemistry, genetics and cell biology to attack these biological problems. A second, minor Hsp70 is also present in the mitochondrial matrix. Studies of this Hsp70 led to our uncovering of a complex system in the mitochondrial matrix required for iron homeostasis and Fe-S cluster formation. Unraveling the mechanism of action of this Hsp70 and the system of iron homeostasis in mitochondria will be one focus of the lab in coming years.
Proteins can exist in more than one conformation.
Occasionally protein conformations can be self-propagating and therefore are referred to as prions. Yeast contains several prions whose conformation is affected by Hsp40 and Hsp70 chaperones. Our goal is to understand the mechanism by which these chaperones affect these self-replicating forms of proteins. Heat shock proteins act as molecular chaperones in proteinfolding and translocation. E.A. Craig, N. Zufall O. von Ahsen, N. Pfanner and W. Voos.