Domain

Gamma-carboxyglutamic acid-rich (GLA) domain (IPR000294)

Short name: GLA_domain

Domain relationships

None.

Description

The GLA (gamma-carboxyglutamic acid-rich) domain contains glutamate residues that have been post-translationally modified by vitamin K-dependent carboxylation to form gamma-carboxyglutamate (Gla) [PMID: 18374189, PMID: 11818531, PMID: 18374194]. All glutamic acid (Glu) residues present in the GLA domain are potential carboxylation sites; in coagulation proteins, all Gu residues are modified to Gla, while in osteocalcin and matrix Gla proteins only some Glu residues are modified to Gla.

The GLA domain is responsible for the high-affinity binding of calcium ions. It starts at the N-terminal extremity of the mature form of proteins and ends with a conserved aromatic residue; a conserved Gla-x(3)-Gla-x-Cys motif [PMID: 3317405] is found in the middle of the domain which seems to be important for substrate recognition by the carboxylase.

The 3D structure of the GLA domain has been solved [PMID: 7713897, PMID: 8663165]. Calcium ions induce conformational changes in the GLA domain that and are necessary for the proper folding of the GLA domain. A common structural feature of functional GLA domains is the clustering of N-terminal hydrophobic residues into a hydrophobic patch that mediates interaction with the cell surface membrane [PMID: 8663165].

Proteins known to contain a GLA domain include [PMID: 18373251]:

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005509 calcium ion binding

Cellular Component

GO:0005576 extracellular region

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PRINTS
SUPERFAMILY
Pfam
PROSITE patterns
SMART
PROSITE profiles