InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: COPB1

Summary

InnateDB Protein

IDBP-33090.6

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

COPB1

Protein Name

coatomer protein complex, subunit beta 1

Synonyms

COPB;

Species

Homo sapiens

Ensembl Protein

ENSP00000249923

InnateDB Gene

IDBG-33088 (COPB1)

Protein Structure

UniProt Annotation

Function

The coatomer is a cytosolic protein complex that binds to dilysine motifs and reversibly associates with Golgi non- clathrin-coated vesicles, which further mediate biosynthetic protein transport from the ER, via the Golgi up to the trans Golgi network. Coatomer complex is required for budding from Golgi membranes, and is essential for the retrograde Golgi-to-ER transport of dilysine-tagged proteins. In mammals, the coatomer can only be recruited by membranes associated to ADP-ribosylation factors (ARFs), which are small GTP-binding proteins; the complex also influences the Golgi structural integrity, as well as the processing, activity, and endocytic recycling of LDL receptors. Plays a functional role in facilitating the transport of kappa- type opioid receptor mRNAs into axons and enhances translation of these proteins. Required for limiting lipid storage in lipid droplets. Involved in lipid homeostasis by regulating the presence of perilipin family members PLIN2 and PLIN3 at the lipid droplet surface and promoting the association of adipocyte surface triglyceride lipase (PNPLA2) with the lipid droplet to mediate lipolysis (By similarity). Involved in the Golgi disassembly and reassembly processes during cell cycle. Involved in autophagy by playing a role in early endosome function. Plays a role in organellar compartmentalization of secretory compartments including endoplasmic reticulum (ER)-Golgi intermediate compartment (ERGIC), Golgi, trans-Golgi network (TGN) and recycling endosomes, and in biosynthetic transport of CAV1. Promotes degradation of Nef cellular targets CD4 and MHC class I antigens by facilitating their trafficking to degradative compartments. {ECO:0000250, ECO:0000269PubMed:18385291, ECO:0000269PubMed:18725938, ECO:0000269PubMed:19364919, ECO:0000269PubMed:20056612}.

Subcellular Localization

Cytoplasm. Golgi apparatus membrane; Peripheral membrane protein; Cytoplasmic side. Cytoplasmic vesicle, COPI-coated vesicle membrane; Peripheral membrane protein; Cytoplasmic side. Cell membrane. Endoplasmic reticulum- Golgi intermediate compartment. Note=The coatomer is cytoplasmic or polymerized on the cytoplasmic side of the Golgi, as well as on the vesicles/buds originating from it. Proteolytic cleavage by CAPN8 triggers translocation from Golgi to cytoplasm (By similarity). Found in perinuclear vesicular-tubular clusters (VTCs) and in the Golgi region where associated with vesicles, buds and rims of the Golgi stack (By similarity). Occasionally present at the trans-side of Golgi, but mainly present at the cis- Golgi side in transitional areas (TA), on so-called peripheral elements (PE) consisting of tubules and vesicles located between the cup-shaped transitional elements (TE) of the rough endoplasmic reticulum (RER) and the cis-most Golgi cisternae (By similarity). Present in cytoplasm, not associated with visible coats or membranes, with a minor fraction present on small clusters of tubules and vesicles (By similarity). Some association with high- density and low-density microsomes and mitochondria/nuclei fraction (By similarity). Very little found in plasma membrane fraction (By similarity). {ECO:0000250}.

Disease Associations

Tissue Specificity

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 88 experimentally validated interaction(s) in this database.
They are also associated with 5 interaction(s) predicted by orthology.

Experimentally validated
Total	88 [view]
Protein-Protein	87 [view]
Protein-DNA	1 [view]
Protein-RNA	0
DNA-DNA	0
RNA-RNA	0
DNA-RNA	0

Predicted by orthology
Total	5 [view]

Gene Ontology

Molecular Function

Accession	GO Term
GO:0005198	structural molecule activity
GO:0005488	binding
GO:0005515	protein binding

Biological Process

GO:0006886	intracellular protein transport
GO:0006890	retrograde vesicle-mediated transport, Golgi to ER
GO:0006891	intra-Golgi vesicle-mediated transport
GO:0016032	viral process
GO:0016192	vesicle-mediated transport
GO:0048205	COPI coating of Golgi vesicle
GO:0061024	membrane organization

Cellular Component

GO:0000139	Golgi membrane
GO:0005737	cytoplasm
GO:0005793	endoplasmic reticulum-Golgi intermediate compartment
GO:0005794	Golgi apparatus
GO:0005798	Golgi-associated vesicle
GO:0005829	cytosol
GO:0005886	plasma membrane
GO:0016020	membrane
GO:0030117	membrane coat
GO:0030126	COPI vesicle coat
GO:0030137	COPI-coated vesicle
GO:0043231	intracellular membrane-bounded organelle

Protein Structure and Domains

PDB ID

InterPro

IPR002553 Clathrin/coatomer adaptor, adaptin-like, N-terminal
IPR011710 Coatomer beta subunit, C-terminal
IPR016024 Armadillo-type fold
IPR016460 Coatomer beta subunit (COPB1)

PFAM

PF01602
PF07718

PRINTS

PIRSF

PIRSF005727

SMART

TIGRFAMs

Post-translational Modifications

Modification

Cross-References

SwissProt

P53618