| Primary Identifier | IPR041870 | Type | Domain |
| Short Name | ERp44_PDI_b |
| description | This entry represents the first redox inactive TRX-like domain b found in endoplasmic reticulum resident protein 44 (ERp44). ERp44 is an endoplasmic reticulum (ER)-resident protein, induced during stress, and involved in thiol-mediated ER retention. It contains an N-terminal TRX domain with a CXFS motif followed by two redox inactive TRX-like domains, homologous to the b and b' domains of PDI. Through the formation of reversible mixed disulfides, ERp44 mediates the ER localization of Ero1alpha, a protein that oxidizes protein disulfide isomerases into their active form [, ]. ERp44 also prevents the secretion of unassembled cargo protein with unpaired cysteines. ERp44 also modulates the activity of inositol 1,4,5-triphosphate type I receptor (IP3R1), an intracellular channel protein that mediates calcium release from the ER to the cytosol []. Similar to PDI, the b domain of ERp44 is likely involved in binding to substrates. |
