Domain

EMI domain (IPR011489)

Short name: EMI_domain

Domain relationships

None.

Description

The EMI domain, first named after its presence in proteins of the EMILIN family, is a small cysteine-rich module of around 75 amino acids. The EMI domain is most often found at the N terminus of metazoan extracellular proteins that are forming or are compatible with multimer formation [PMID: 11068053]. It is found in association with other domains, such as C1q, laminin-type EGF-like, collagen-like, FN3, WAP, ZP or FAS1 [PMID: 12507493]. It has been suggested that the EMI domain could be a protein-protein interaction module, as the EMI domain of EMILIN-1 was found to interact with the C1q domain of EMILIN-2 [PMID: 11068053].

The EMI domain possesses six highly conserved cysteines residues, which likely form disulphide bonds. Other key features of the EMI domain are the C-C-x-G-[WYFH] pattern, a hydrophobic position just preceding the first cysteine (Cys1) of the domain and a cluster of hydrophobic residues between Cys3 and Cys4. The EMI domain could be made of two sub-domains, the fold of the second one sharing similarities with the C-terminal sub-module characteristic of EGF-like domains [PMID: 12507493].

Proteins known to contain a EMI domain include:

  • Vertebrate Emilins, extracellular matrix glycoproteins.
  • Vertebrate Multimerins, extracellular matrix glycoproteins.
  • Vetebrate Emu proteins, which could interact with several different extracellular matrix components and serve to connect and integrate the function of multiple partner molecules.
  • Vertebrate beta-IG-H3.
  • Vertebrate osteoblast-specific factor 2 (OSF-2).
  • Mammalian NEU1/NG3 proteins.
  • Drosophila midline fasciclin.
  • Caenorhabditis elegans ced-1, a transmembrane receptor that mediates cell corpse engulfment.

The Pfam alignment for this domain is truncated at the C terminus and does not include the final cysteine [PMID: 12507493]. This is to stop the family overlapping with other domains.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005515 protein binding

Cellular Component

No terms assigned in this category.

Contributing signatures

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