A GTPase-activating protein controls Rab5 function in endocytic trafficking.
Nat Cell Biol
; 7(9): 887-93, 2005 Sep.
Article
em En
| MEDLINE
| ID: mdl-16086013
ABSTRACT
Rab-family GTPases are conserved regulators of membrane trafficking that cycle between inactive GDP-bound and activated GTP-bound states. A key determinant of Rab function is the lifetime of the GTP-bound state. As Rabs have a low intrinsic rate of GTP hydrolysis, this process is under the control of GTP-hydrolysis-activating proteins (GAPs). Due to the large number of Rabs and GAPs that are encoded by the human genome, it has proven difficult to assign specific functional relationships to these proteins. Here, we identify a Rab5-specific GAP (RabGAP-5), and show that RN-Tre (previously described as a Rab5 GAP) acts on Rab41. RabGAP-5 overexpression triggers a loss of the Rab5 effector EEA1 from endosomes and blocks endocytic trafficking. By contrast, depletion of RabGAP-5 results in increased endosome size, more endosome-associated EEA1, and disrupts the trafficking of EGF and LAMP1. RabGAP-5 therefore limits the amount of activated Rab5, and thereby regulates trafficking through endosomes.
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Base de dados:
MEDLINE
Assunto principal:
Endossomos
/
Membrana Celular
/
Proteínas rab5 de Ligação ao GTP
/
Proteínas Ativadoras de GTPase
/
Endocitose
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article