Taxonomic distribution of proteins containing EMP24_GP25L domains

The tree below includes only several representative species and genera. The complete taxonomic breakdown of all proteins containing EMP24_GP25L domains can be accessed here. Click the counts or percentage values to display the corresponding proteins.

The GOLD domain, a novel protein module involved in Golgi function and secretion.

Anantharaman V, Aravind L
Genome Biol. 2002; 3: 23-23

BACKGROUND: Members of the p24 (p24/gp25L/emp24/Erp) family of proteins have beenshown to be critical components of the coated vesicles that are involved in thetransportation of cargo molecules from the endoplasmic reticulum to the Golgicomplex. The p24 proteins form hetero-oligomeric complexes and are believed tofunction as receptors for specific secretory cargo. RESULTS: Using sensitivesequence-profile analysis methods, we identified a novel beta-strand-rich domain,the GOLD (Golgi dynamics) domain, in the p24 proteins and several other proteins with roles in Golgi dynamics and secretion. This domain is predicted to mediatediverse protein-protein interactions. Other than in the p24 proteins, the GOLDdomain is always found combined with lipid- or membrane-association domains such as the pleckstrin homology (PH), Sec14p and FYVE domains. CONCLUSIONS: Theidentification of the GOLD domain could aid in directed investigation of the roleof the p24 proteins in the secretion process. The newly detected group ofGOLD-domain proteins, which might simultaneously bind membranes and otherproteins, point to the existence of a novel class of adaptors that could have arole in the assembly of membrane-associated complexes or in regulating assemblyof cargo into membranous vesicles.

gp25L/emp24/p24 protein family members of the cis-Golgi network bind both COP Iand II coatomer.

Dominguez M, Dejgaard K, Fullekrug J, Dahan S, Fazel A, Paccaud JP, Thomas DY, Bergeron JJ, Nilsson T
J Cell Biol. 1998; 140: 751-65

Abstract. Five mammalian members of the gp25L/ emp24/p24 family have beenidentified as major constituents of the cis-Golgi network of rat liver and HeLacells. Two of these were also found in membranes of higher density (correspondingto the ER), and this correlated with their ability to bind COP I in vitro. Thisbinding was mediated by a K(X)KXX-like retrieval motif present in the cytoplasmicdomain of these two members. A second motif, double phenylalanine (FF), presentin the cytoplasmic domain of all five members, was shown to participate in thebinding of Sec23 (COP II). This motif is part of a larger one, similar to theF/YXXXXF/Y strong endocytosis and putative AP2 binding motif. In vivo mutational analysis confirmed the roles of both motifs so that when COP I binding wasexpected to be impaired, cell surface expression was observed, whereas mutationof the Sec23 binding motif resulted in a redistribution to the ER. Surprisingly, upon expression of mutated members, steady-state distribution of unmutated onesshifted as well, presumably as a consequence of their observed oligomericproperties.