FIG. 2.

Structure of the mitochondrial Lon protease. (A) The Lon protease consists of three domains: an N-terminal domain that recognizes oxidized substrates, an ATPase domain that hydrolyzes ATP to facilitate ring opening, and a proteolytic domain that degrades damaged proteins. (B) Top view of the Lon protease. (C) A side view of the Lon protease, showing the recognition and degradation of only oxidized proteins due to exposure of hydrophobic residues. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars