Alpha-2-macroglobulin receptor-associated protein, domain 1 (IPR009066)

Short name: MG_RAP_rcpt_1

Overlapping homologous superfamilies

Domain relationships



The alpha-2-macroglobulin receptor-associated protein (RAP) is a glycoprotein that binds to the alpha-2-macroglobulin receptor, as well as to other members of the low density lipoprotein receptor family (IPR002172). RAP acts to inhibit the binding of all know ligands for these receptors, and may prevent receptor aggregation and degradation in the endoplasmic reticulum, thereby acting as a molecular chaperone [PMID: 9207124]. RAP may be under the regulatory control of calmodulin, since it is able to bind calmodulin and be phosphorylated by calmodulin-dependent kinase II (IPR002048).

RAP is comprised of three domains. Both domains 1 and 3 are involved in binding to the alpha-2-macroglobulin receptor, while domain 1 is also involved in inhibiting the binding of activated alpha-2-macroglobulin (IPR001599). Structural studies have revealed the RAP domain 1 to be comprised of a partly opened bundle of three helices, the first one being shorter than the other two.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.