The functional interaction of mitochondrial Hsp70s with the escort protein Zim17 is critical for Fe/S biogenesis and substrate interaction at the inner membrane preprotein translocase
12.09.2013
Lewrenz I, Rietzschel N, Guiard B, Lill R, van der Laan M, Voos W.
J Biol Chem. 2013;288(43):30931-43
Biogenesis of mitochondrial matrix proteins requires the translocation of their precursor forms across both mitochondrial membranes, processing of the amino-terminal presequences and folding of the mature proteins into their active conformations. Mitochondrial members of the heat shock protein 70 family (mtHsp70s) are required for both import and maturation of matrix proteins. Several co-chaperones cooperate with mtHsp70s to regulate their membrane association, ATPase activity and substrate interaction. Different views have been reported on the role of the co-chaperone Zim17. Using conditional zim17 yeast mutants we now show that Zim17 not only prevents the aggregation of mtHsp70s, but also plays an important role in the biogenesis of Fe/S protein and regulates mtHsp70-preprotein interactions during protein import across the inner mitochondrial membrane.
