Article

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

National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
Genome biology (Impact Factor: 10.81). 02/2002; 3(5):research0023. DOI: 10.1186/gb-2002-3-5-research0023
Source: PubMed

ABSTRACT

Members of the p24 (p24/gp25L/emp24/Erp) family of proteins have been shown to be critical components of the coated vesicles that are involved in the transportation of cargo molecules from the endoplasmic reticulum to the Golgi complex. The p24 proteins form hetero-oligomeric complexes and are believed to function as receptors for specific secretory cargo.
Using sensitive sequence-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 mediate diverse protein-protein interactions. Other than in the p24 proteins, the GOLD domain is always found combined with lipid- or membrane-association domains such as the pleckstrin homology (PH), Sec14p and FYVE domains.
The identification of the GOLD domain could aid in directed investigation of the role of the p24 proteins in the secretion process. The newly detected group of GOLD-domain proteins, which might simultaneously bind membranes and other proteins, point to the existence of a novel class of adaptors that could have a role in the assembly of membrane-associated complexes or in regulating assembly of cargo into membranous vesicles.

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Available from: Vivek Anantharaman, Jul 27, 2015
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    • "The cytoplasmic tail contains binding motifs for the vesicle coat complexes COPI and COPII [11]. At the luminal side, p24 proteins have an N-terminal Golgi dynamics (GOLD) domain, which may play a role in the incorporation of cargo into transport vesicles [9, 12]. The N-terminal luminal domain contains two conserved cysteine residues [13], presumably forming a disulfide bond within the GOLD domain [9]. "
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    • "All p24 proteins consist of a large luminal portion, which includes the GOLD (GOLgi Dynamics) and coiled-coil domains, a single transmembrane domain, and a short cytoplasmic C-terminus which contains motifs for COPI and COPII binding (Supplementary Fig. S1 available at JXB online). Whereas the transmembrane domain seems to recognize a single sphingolipid species (Contreras et al., 2012), the luminal GOLD domain is predicted to be involved in specific protein–protein interactions and has been postulated to interact with putative cargo proteins (Anantharaman and Aravind, 2002; Carney and Bowen, 2004). The coiled-coil domain of p24 proteins enables intermolecular interactions between copies of the same protein, but also between different p24 proteins. "
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    • "While it is likely that the complex is a tetramer or larger, the exact composition of the complex and how these components interact with each other in the complex are currently unclear. All p24 proteins have a similar domain organization consisting of an N-terminal signal sequence, a luminal domain termed the GOLD domain (for GOLgi Dynamics)[32], a helical region with a central coiled-coil domain, a transmembrane domain and a short cytoplasmic domain[26](Figs. 1B, 2B). "
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