Protein disulfide isomerase A1 (PDIA1); Protein disulfide isomerase A3 (PDIA3) (PDIA1 (for A1); PDIA3 (for A3))

Protein disulfide isomerase A1 and A3 are enzymes located predominantly in the endoplasmic reticulum, where they catalyze the formation, isomerization, and reduction of disulfide bonds necessary for proper folding of nascent proteins. PDIA1 (often referred to simply as PDI) acts broadly as an oxireductase and chaperone, supporting protein maturation, signal transduction, and cellular homeostasis. PDIA3 (also known as ERp57 or Grp58) is structurally similar, with additional roles in antigen presentation (as a key component of the MHC class I peptide-loading complex). Both enzymes are implicated in cancer, neurodegenerative disorders, and immune regulation; they are considered promising but challenging therapeutic targets because of their critical role in normal protein folding and cellular function.

Other names

PDIProtein disulfide-isomeraseERp57Grp58Protein disulfide-isomerase A3

Drugs targeting Protein Disulfide Isomerase A1/A3 typically act through inhibition of their thiol-disulfide oxidoreductase activity. This leads to disruption of protein folding cycles and ER-associated degradation, which can induce ER stress and/or apoptosis in target cells, such as cancer cells.