Coenzyme A protects against ferroptosis via CoAlation of mitochondrial thioredoxin reductase
Chao-Chieh Lin, Yi-Tzu Lin, Ssu-Yu Chen, Yasaman Setayeshpour, Yubin Chen, Denise E. Dunn, Taylor Nguyen, Alexander A. Mestre, Adrija Banerjee, Lalitha Guruprasad, Erik J. Soderblom, Guo-Fang Zhang, Chen-Yong Lin, Valeriy Filonenko, Suh Young Jeong, Scott R. Floyd, Susan J. Hayflick, Ivan Gout, Jen-Tsan Chi
Chao-Chieh Lin, Yi-Tzu Lin, Ssu-Yu Chen, Yasaman Setayeshpour, Yubin Chen, Denise E. Dunn, Taylor Nguyen, Alexander A. Mestre, Adrija Banerjee, Lalitha Guruprasad, Erik J. Soderblom, Guo-Fang Zhang, Chen-Yong Lin, Valeriy Filonenko, Suh Young Jeong, Scott R. Floyd, Susan J. Hayflick, Ivan Gout, Jen-Tsan Chi
View: Text | PDF
Research Article Cell biology Metabolism

Coenzyme A protects against ferroptosis via CoAlation of mitochondrial thioredoxin reductase

Abstract

The cystine-xCT transporter/glutathione/GPX4 axis is the canonical pathway protecting cells from ferroptosis. Whereas GPX4-targeting ferroptosis-inducing compounds (FINs) act independently of mitochondria, xCT-targeting FINs require mitochondrial lipid peroxidation, though the mechanism remains unclear. Because cysteine is also a precursor for coenzyme A (CoA) biosynthesis, here, we demonstrated that CoA supplementation selectively prevented ferroptosis triggered by xCT inhibition by regulating the mitochondrial thioredoxin system. Our data showed that CoA regulated the in vitro enzymatic activity of mitochondrial thioredoxin reductase-2 (TXNRD2) by covalently modifying the thiol group of cysteine (CoAlation) on Cys-483. Replacing Cys-483 with alanine on TXNRD2 abolished its enzymatic activity and ability to protect cells against ferroptosis. Targeting xCT to limit cysteine import and, therefore, CoA biosynthesis reduced CoAlation on TXNRD2. Furthermore, the fibroblasts from patients with disrupted CoA metabolism had increased mitochondrial lipid peroxidation. In organotypic brain slice cultures, inhibition of CoA biosynthesis led to an oxidized thioredoxin system, increased mitochondrial lipid peroxidation, and loss of cell viability, which were all rescued by ferrostatin-1. These findings identified CoA-mediated posttranslational modification to regulate the thioredoxin system as an alternative ferroptosis protection pathway with potential clinical relevance for patients with disrupted CoA metabolism.

Authors

Chao-Chieh Lin, Yi-Tzu Lin, Ssu-Yu Chen, Yasaman Setayeshpour, Yubin Chen, Denise E. Dunn, Taylor Nguyen, Alexander A. Mestre, Adrija Banerjee, Lalitha Guruprasad, Erik J. Soderblom, Guo-Fang Zhang, Chen-Yong Lin, Valeriy Filonenko, Suh Young Jeong, Scott R. Floyd, Susan J. Hayflick, Ivan Gout, Jen-Tsan Chi

×

Figure 2

CoA regulates mitochondrial TXN system.

Options: View larger image (or click on image) Download as PowerPoint
CoA regulates mitochondrial TXN system. (A) HT-1080 cells were treated w...
(A) HT-1080 cells were treated with CoA (100 μM) alone or in combination with the TXN inhibitor ferroptocide (2 μM), during erastin-induced ferroptosis (20 hours). Cell viability was quantified using the Cell-Titer Glo assay. (B) TXNRD activity was significantly reduced after erastin treatment (1.25 μM, 16 hours) in HT-1080 cell lysates, and this repression was restored by CoA (100 μM) supplementation. (C) Pooled siRNA knockdown of TXN2, but not TXN1, abolished CoA-mediated protection from ferroptosis, indicating a specific role for mitochondrial TXN2. siNC, negative control siRNA. (D) Erastin disrupted the interaction between TXNRD2 and TXN2, which was restored by CoA. HT-1080 cells overexpressing TXNRD2 and TXN2 were treated with erastin (2.5 μM, 18 hours), with or without CoA, and lysed in NEM buffer for coimmunoprecipitation analysis. (E) Western blot analysis revealed that erastin reduced the levels of PRDX3 monomers (reduced, active forms), which was reversed by CoA supplementation. (F) Monomer/dimer ratios of PRDX3 were quantified in cells treated with erastin and CoA. Data were analyzed by 1-way ANOVA and Tukey’s test. (A–C) Data were analyzed by 2-way ANOVA and Šídák’s test; n = 3 biological replicates. Data are reported as mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001.