GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:14973189

From GONUTS
Jump to: navigation, search
Citation

Padilla, PI, Pacheco-Rodriguez, G, Moss, J and Vaughan, M (2004) Nuclear localization and molecular partners of BIG1, a brefeldin A-inhibited guanine nucleotide-exchange protein for ADP-ribosylation factors. Proc. Natl. Acad. Sci. U.S.A. 101:2752-7

Abstract

Brefeldin A-inhibited guanine nucleotide-exchange protein 1 (BIG1) is an approximately 200-kDa brefeldin A-inhibited guanine nucleotide-exchange protein that preferentially activates ADP-ribosylation factor 1 (ARF1) and ARF3. BIG1 was found in cytosol in a multiprotein complex with a similar ARF-activating protein, BIG2, which is also an A kinase-anchoring protein. In HepG2 cells growing with serum, BIG1 was primarily cytosolic and Golgi-associated. After incubation overnight without serum, a large fraction of endogenous BIG1 was in the nuclei. By confocal immunofluorescence microscopy, BIG1 was localized with nucleoporin p62 at the nuclear envelope (probably during nucleocytoplasmic transport) and also in nucleoli, clearly visible against the less concentrated overall matrix staining. BIG1 was also identified by Western blot analyses in purified subnuclear fractions (e.g., nucleoli and nuclear matrix). Antibodies against BIG1, nucleoporin, or nucleolin coimmunoprecipitated the other two proteins from purified nuclei. In contrast, BIG2 was not associated with nuclear BIG1. Also of note, ARF was never detected among proteins precipitated from purified nuclei by anti-BIG1 antibodies, although microscopically the two proteins do appear sometimes to be colocalized in the nucleus. These data are consistent with independent intracellular movements and actions of BIG1 and BIG2, and they are also evidence of the participation of BIG1 in both Golgi and nuclear functions.

Links

PubMed PMC365693 Online version:10.1073/pnas.0307345101

Keywords

Adenosine Diphosphate Ribose/metabolism; Brefeldin A/pharmacology; Cell Line, Tumor; Cell Nucleolus/drug effects; Cell Nucleolus/metabolism; Culture Media; GTP-Binding Proteins/drug effects; GTP-Binding Proteins/metabolism; Golgi Apparatus/metabolism; Guanine Nucleotide Exchange Factors/metabolism; Humans; Liver Neoplasms; Microscopy, Confocal; Microscopy, Fluorescence; Protein Transport; Tacrolimus/pharmacology

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

HUMAN:BIG1

located_in

GO:0005730: nucleolus

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:BIG1

part_of

GO:0005730: nucleolus

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

Notes

See also

References

See Help:References for how to manage references in GONUTS.