1. Cooperative Protein Folding by Two Protein Thiol Disulfide Oxidoreductases and ERO1 in Soybean
- Author
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Yurika Naruo, Reiko Urade, Yuichiro Tsuchi, Katsunori Koishihara, Motonori Matsusaki, Ryuta Mita, Akiho Hirose, Kumiko Hara, Kensuke Iwasaki, Taro Masuda, and Aya Okuda
- Subjects
0301 basic medicine ,Protein Folding ,genetic structures ,Physiology ,Protein Disulfide-Isomerases ,Plant Science ,Oxidative phosphorylation ,Endoplasmic Reticulum ,Catalysis ,Active center ,03 medical and health sciences ,Oxidoreductase ,Genetics ,Disulfides ,Protein disulfide-isomerase ,chemistry.chemical_classification ,Endoplasmic reticulum ,Oxidative folding ,Protein Disulfide Reductase (Glutathione) ,Articles ,Recombinant Proteins ,Yeast ,030104 developmental biology ,chemistry ,Biochemistry ,Protein folding ,Soybeans ,Oxidoreductases ,Oxidation-Reduction - Abstract
Most proteins produced in the endoplasmic reticulum (ER) of eukaryotic cells fold via disulfide formation (oxidative folding). Oxidative folding is catalyzed by protein disulfide isomerase (PDI) and PDI-related ER protein thiol disulfide oxidoreductases (ER oxidoreductases). In yeast and mammals, ER oxidoreductin-1s (Ero1s) supply oxidizing equivalent to the active centers of PDI. In this study, we expressed recombinant soybean Ero1 (GmERO1a) and found that GmERO1a oxidized multiple soybean ER oxidoreductases, in contrast to mammalian Ero1s having a high specificity for PDI. One of these ER oxidoreductases, GmPDIM, associated in vivo and in vitro with GmPDIL-2, was unable to be oxidized by GmERO1a. We therefore pursued the possible cooperative oxidative folding by GmPDIM, GmERO1a, and GmPDIL-2 in vitro and found that GmPDIL-2 synergistically accelerated oxidative refolding. In this process, GmERO1a preferentially oxidized the active center in the A': domain among the A: , A': , and B: domains of GmPDIM. A disulfide bond introduced into the active center of the A': domain of GmPDIM was shown to be transferred to the active center of the A: domain of GmPDIM and the A: domain of GmPDIM directly oxidized the active centers of both the A: or A': domain of GmPDIL-2. Therefore, we propose that the relay of an oxidizing equivalent from one ER oxidoreductase to another may play an essential role in cooperative oxidative folding by multiple ER oxidoreductases in plants.
- Published
- 2015