In vivo mitochondrial matrix proteome profiling reveals RTN4IP1/OPA10 as an antioxidant NADPH oxidoreductase

Park, I.; Kim, K.-e.; Kim, J.; Bae, S.; Jung, M.; Choi, J.; Kwak, C.; Kang, M.-G.; Yoo, C.-M.; Mun, J. Y.; Liu, K.-H.; Kim, J.-S.; Suh, J. M.; Rhee, H.-W.

doi:10.1101/2021.10.14.464368

bioRxiv · 10.1101/2021.10.14.464368

In vivo mitochondrial matrix proteome profiling reveals RTN4IP1/OPA10 as an antioxidant NADPH oxidoreductase

Park, I.·Kim, K.-e.·Kim, J.·Bae, S.·Jung, M.·Choi, J.·Kwak, C.·Kang, M.-G.·Yoo, C.-M.·Mun, J. Y.·Liu, K.-H.·Kim, J.-S.·Suh, J. M.·Rhee, H.-W.

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Abstract

Targeting proximity labeling enzymes to specific cellular locations is a viable strategy for profiling subcellular proteomes. Here, we generated transgenic mice expressing a mitochondrial matrix-targeted ascorbate peroxidase (MAX-Tg) to analyze tissue-specific matrix proteomes. Desthiobiotin-phenol labeling of muscle tissues from MAX-Tg mice allowed for efficient profiling of mitochondrial-localized proteins in these tissues. Comparative analysis of matrix proteomes from MAX-Tg muscle tissues revealed differential enrichment of mitochondrial proteins related to energy production in between different muscle groups. Reticulon 4 interacting protein 1 (RTN4IP1), also known as Optic Atrophy-10 (OPA10), was highly enriched in the cardiac and soleus muscles and was found to localize to the mitochondrial matrix via a strong mitochondrial targeting sequence at its N-terminus. Protein structure analysis revealed that RTN4IP1 is an NADPH oxidoreductase with structural homology to bacterial quinone oxidoreductase. Enzymatic activity assays, interactome analysis, and metabolite profiling confirmed a function for RTN4IP1 in coenzyme Q (CoQ) biosynthesis. Rtn4ip1-knockout C2C12 cells had reduced CoQ9 levels, were vulnerable to oxidative stress, and had decreased oxygen consumption rates and ATP production. Collectively, RTN4IP1 is a mitochondrial antioxidant NADPH oxidoreductase supporting oxidative phosphorylation activity in muscle tissue.

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Park, I., Kim, K.-e., Kim, J., Bae, S., Jung, M., Choi, J., Kwak, C., Kang, M.-G., Yoo, C.-M., Mun, J. Y., Liu, K.-H., Kim, J.-S., Suh, J. M., Rhee, H.-W.. 2021-10-14. In vivo mitochondrial matrix proteome profiling reveals RTN4IP1/OPA10 as an antioxidant NADPH oxidoreductase. https://doi.org/10.1101/2021.10.14.464368

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