Cytohesins are cytoplasmic ErbB receptor activators.
Cell
; 143(2): 201-11, 2010 Oct 15.
Article
em En
| MEDLINE
| ID: mdl-20946980
ABSTRACT
Signaling by ErbB receptors requires the activation of their cytoplasmic kinase domains, which is initiated by ligand binding to the receptor ectodomains. Cytoplasmic factors contributing to the activation are unknown. Here we identify members of the cytohesin protein family as such factors. Cytohesin inhibition decreased ErbB receptor autophosphorylation and signaling, whereas cytohesin overexpression stimulated receptor activation. Monitoring epidermal growth factor receptor (EGFR) conformation by anisotropy microscopy together with cell-free reconstitution of cytohesin-dependent receptor autophosphorylation indicate that cytohesins facilitate conformational rearrangements in the intracellular domains of dimerized receptors. Consistent with cytohesins playing a prominent role in ErbB receptor signaling, we found that cytohesin overexpression correlated with EGF signaling pathway activation in human lung adenocarcinomas. Chemical inhibition of cytohesins resulted in reduced proliferation of EGFR-dependent lung cancer cells in vitro and in vivo. Our results establish cytohesins as cytoplasmic conformational activators of ErbB receptors that are of pathophysiological relevance.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Adenocarcinoma
/
Receptores Proteína Tirosina Quinases
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Fatores de Troca do Nucleotídeo Guanina
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Receptores ErbB
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Neoplasias Pulmonares
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article