The extracellular Ero1α/PDI electron transport system regulates platelet function by increasing glutathione reduction potential
Lu Wang,
Xi Wang,
Xiying Lv,
Qiushuo Jin,
Hongcai Shang,
Chih-chen Wang,
Lei Wang
Affiliations
Lu Wang
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China; Corresponding author.
Xi Wang
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
Xiying Lv
Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, 100700, China
Qiushuo Jin
Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, 100700, China
Hongcai Shang
Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, 100700, China
Chih-chen Wang
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
Lei Wang
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China; Corresponding author. National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
Protein disulfide isomerase (PDI), an oxidoreductase, possesses two vicinal cysteines in the -Cys-Gly-His-Cys-motif that either form a disulfide bridge (S–S) or exist in a sulfhydryl form (-SH), forming oxidized or reduced PDI, respectively. PDI has been proven to be critical for platelet aggregation, thrombosis, and hemostasis, and PDI inhibition is being evaluated as a novel antithrombotic strategy. The redox states of functional PDI during the regulation of platelet aggregation, however, remain to be elucidated. Endoplasmic reticulum (ER) oxidoreductin-1α (Ero1α) and PDI constitute the pivotal oxidative folding pathway in the ER and play an important role in ER redox homeostasis. Whether Ero1α and PDI constitute an extracellular electron transport pathway to mediate platelet aggregation is an open question. Here, we found that oxidized but not reduced PDI promotes platelet aggregation. On the platelet surface, Ero1α constitutively oxidizes PDI and further regulates platelet aggregation in a glutathione-dependent manner. The Ero1α/PDI system oxidizes reduced glutathione (GSH) and establishes a reduction potential optimal for platelet aggregation. Therefore, platelet aggregation is mediated by the Ero1α-PDI-GSH electron transport system on the platelet surface. We further showed that targeting the functional interplay between PDI and Ero1α by small molecule inhibitors may be a novel strategy for antithrombotic therapy.
