Protein disulfide isomerase in redox cell signaling and homeostasis

• Published in: Free radical biology & medicine 2012-05, Vol.52 (9), p.1954-1969
• Main Authors: Laurindo, Francisco R.M., Pescatore, Luciana A., de Castro Fernandes, Denise
• Format: Article
• Language: English
• Subjects: adhesion; angiotensin II; Animals; coagulation; disulfide bonds; endoplasmic reticulum; Endoplasmic reticulum stress; Free radicals; Homeostasis; Humans; macrophages; NADPH oxidase; neutrophils; oxidants; Oxidation-Reduction; parasites; peroxiredoxin; phagocytosis; phosphorylation; post-translational modification; Protein disulfide isomerase; Protein Disulfide-Isomerases - metabolism; proteinases; proteins; reactive oxygen species; Redox signaling; Signal Transduction; Thiols; Thioredoxin; thrombosis; Unfolded protein response; viruses
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/j.freeradbiomed.2012.02.037

Thiol proteins may potentially act as redox signaling adaptor proteins, adjusting reactive oxygen species intermediates to specific signals and redox signals to cell homeostasis. In this review, we discuss redox effects of protein disulfide isomerase (PDI), a thioredoxin superfamily oxidoreductase from the endoplasmic reticulum (ER). Abundantly expressed PDI displays ubiquity, interactions with redox and nonredox proteins, versatile effects, and several posttranslational modifications. The PDI family contains >20 members with at least some apparent complementary actions. PDI has oxidoreductase, isomerase, and chaperone effects, the last not directly dependent on its thiols. PDI is a converging hub for pathways of disulfide bond introduction into ER-processed proteins, via hydrogen peroxide-generating mechanisms involving the oxidase Ero1α, as well as hydrogen peroxide-consuming reactions involving peroxiredoxin IV and the novel peroxidases Gpx7/8. PDI is a candidate pathway for coupling ER stress to oxidant generation. Emerging information suggests a convergence between PDI and Nox family NADPH oxidases. PDI silencing prevents Nox responses to angiotensin II and inhibits Akt phosphorylation in vascular cells and parasite phagocytosis in macrophages. PDI overexpression spontaneously enhances Nox activation and expression. In neutrophils, PDI redox-dependently associates with p47phox and supports the respiratory burst. At the cell surface, PDI exerts transnitrosation, thiol reductase, and apparent isomerase activities toward targets including adhesion and matrix proteins and proteases. Such effects mediate redox-dependent adhesion, coagulation/thrombosis, immune functions, and virus internalization. The route of PDI externalization remains elusive. Such multiple redox effects of PDI may contribute to its conspicuous expression and functional role in disease, rendering PDI family members putative redox cell signaling adaptors. [Display omitted] ► Thiol proteins can act as adaptors for redox signaling and homeostasis. ► PDI (protein disulfide isomerase) has chaperone and thiol redox/isomerase actions. ► Active PDI is located at the endoplasmic reticulum (ER) or cell surface. ► PDI converges with ER-dependent reactive oxygen species sources and NADPH oxidases. ► PDI displays conspicuous expression and functional roles in disease.