Pathways & interactions
Short name: Calret/calnex
Overlapping homologous superfamilies
- Calreticulin/calnexin, P domain superfamily (IPR009033)
- Calreticulin/calnexin (IPR001580)
- Calreticulin (IPR009169)
The calreticulin family is a family of calcium-binding ER chaperonesthat includes calreticulin, calnexin and camlegin [PMID: 12401114].
Calreticulin (calregulin) [PMID: 1497605] is a high-capacity calcium-binding protein which is present in most tissues and located at the periphery of the endoplasmic (ER) and the sarcoplamic reticulum (SR) membranes. It probably plays a role in the storage of calcium in the lumen of the ER and SR and it may well have other important functions.
Structurally, calreticulin is a protein of about 400 amino acid residues consisting of three domains:
- An N-terminal, probably globular, domain of about 180 amino acid residues (N-domain).
- A central domain of about 70 residues (P-domain) which contains three repeats of an acidic 17 amino acid motif. This region binds calcium with a low-capacity, but a high-affinity.
- A C-terminal domain rich in acidic residues and in lysine (C-domain). This region binds calcium with a high-capacity but a low-affinity.