Homologous Superfamily

RAP domain superfamily (IPR036744)

Short name: RAP_sf

Overlapping entries


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, each representing about one-third of the protein, which originated from an apparent triplication of an approximately 100 residue sequence. The second and third domains interact weakly with one another, whereas the first domain is entirely independent [PMID: 14674767]. Structural studies have revealed the first RAP domain to comprise 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.