Scission of COPI and COPII vesicles is independent of GTP hydrolysis.
Traffic
; 14(8): 922-32, 2013 Aug.
Article
em En
| MEDLINE
| ID: mdl-23691917
ABSTRACT
Intracellular transport and maintenance of the endomembrane system in eukaryotes depends on formation and fusion of vesicular carriers. A seeming discrepancy exists in the literature about the basic mechanism in the scission of transport vesicles that depend on GTP-binding proteins. Some reports describe that the scission of COP-coated vesicles is dependent on GTP hydrolysis, whereas others found that GTP hydrolysis is not required. In order to investigate this pivotal mechanism in vesicle formation, we analyzed formation of COPI- and COPII-coated vesicles utilizing semi-intact cells. The small GTPases Sar1 and Arf1 together with their corresponding coat proteins, the Sec23/24 and Sec13/31 complexes for COPII and coatomer for COPI vesicles were required and sufficient to drive vesicle formation. Both types of vesicles were efficiently generated when GTP hydrolysis was blocked either by utilizing the poorly hydrolyzable GTP analogs GTPγS and GMP-PNP, or with constitutively active mutants of the small GTPases. Thus, GTP hydrolysis is not required for the formation and release of COP vesicles.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fator 1 de Ribosilação do ADP
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Vesículas Revestidas pelo Complexo de Proteína do Envoltório
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Proteínas de Transporte Vesicular
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Guanosina Trifosfato
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article