A COPI coat subunit interacts directly with an early-Golgi localized Arf exchange factor.
EMBO Rep
; 10(1): 58-64, 2009 Jan.
Article
em En
| MEDLINE
| ID: mdl-19039328
ABSTRACT
Arf (ADP-ribosylation factor) family small G proteins are crucial regulators of intracellular transport. The active GTP-bound form of Arf interacts with a set of proteins--effectors--which mediate the downstream signalling events of Arf activation. A well-studied class of Arf1 effectors comprises the coat complexes, such as the cis-Golgi-localized COPI (coat protein complex I) coat, and trans-Golgi network-endosomal clathrin coats. At least five different coats require Arf1-GTP to localize to organelle membranes. How a single Arf protein recruits different coat complexes to distinct membrane sites raises the question of how specificity is achieved. Here, we propose a molecular mechanism of this specificity for the COPI coat by showing a direct and specific interaction between a COPI subunit and a cis-Golgi localized subfamily of Arf guanine nucleotide exchange factors (GEFs) that takes place independently of Arf1 activation. In this way, a specific output on Arf1 activation can be programmed before the exchange reaction by the GEF itself.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fator 1 de Ribosilação do ADP
/
Complexo I de Proteína do Envoltório
/
Complexo de Golgi
Limite:
Animals
/
Humans
Idioma:
En
Revista:
EMBO Rep
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Estados Unidos