Cu/Zn Superoxide Dismutase (Sod1) is a highly conserved and abundant metalloenzyme that catalyzes thedisproportionation of superoxide radicals into hydrogen peroxide and molecular oxygen. As a consequence, Sod1serves dual roles in oxidative stress protection and redox signaling by both scavenging cytotoxic superoxideradicals and producing hydrogen peroxide that can be used to oxidize and regulate the activity of downstreamtargets. However, the relative contributions of Sod1 to protection against oxidative stress and redox signaling arepoorly understood. Using the model unicellular eukaryote, Baker's yeast, we found that only a small fraction ofthe total Sod1 pool is required for protection against superoxide toxicity and that this pool is localized to themitochondrial intermembrane space. On the contrary, wefind that much larger amounts of extra-mitochondrialSod1 are critical for peroxide-mediated redox signaling. Altogether, our results force the re-evaluation of thephysiological role of bulk Sod1 in redox biology; namely, we propose that the vast majority of Sod1 in yeast isutilized for peroxide-mediated signaling rather than superoxide scavenging.
Digital Object Identifier (DOI)
Published in Redox Biology, Volume 21, 2019, pages 101064-.
© 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/).
Montllor-Albalate, C., Colin, A. E., Chandrasekharan, B., Bolaji, N., Andersen, J. L., Wayne Outten, F., & Reddi, A. R. (2019). Extra-Mitochondrial CU/Zn Superoxide Dismutase (SOD1) Is Dispensable for Protection Against Oxidative Stress but Mediates Peroxide Signaling in Saccharomyces Cerevisiae. Redox Biology, 21, 101064.