endoplasmic reticulum resident protein 44; ER protein 44; ERp44; thioredoxin domain-containing protein 4 (ERP44, KIAA0573, TXNDC4, UNQ532/PRO1075)

Function

• mediates thiol-dependent retention in the early secretory pathway, forming mixed disulfides with substrate proteins through its conserved CRFS motif
• inhibits the Ca+2 channel activity of ITPR1
• may have a role in the control of oxidative protein folding in the endoplasmic reticulum
• required to retain ERO1L & ERO1LB in the endoplasmic reticulum
• forms mixed disulfides with both ERO1L & ERO1LB & cargo folding intermediates
• directly interacts with ITPR1 (pH-, redox state- & Ca+2- dependent), but not with ITPR2 or ITPR3
• interaction with ITPR1 inversely correlates with Ca+2 concentration (putative)

Structure

contains 1 thioredoxin domain

Compartment

endoplasmic reticulum lumen

Expression

induced by endoplasmic reticulum stress

More general terms

• thioredoxin domain-containing protein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=23071
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:23071
• OMIM: https://mirror.omim.org/entry/609170
• UniProt: http://www.uniprot.org/uniprot/Q9BS26.html