Essential role of the Dishevelled DEP domain in a Wnt-dependent human-cell-based complementation assay.
J Cell Sci
; 129(20): 3892-3902, 2016 10 15.
Article
en En
| MEDLINE
| ID: mdl-27744318
ABSTRACT
Dishevelled (DVL) assembles Wnt signalosomes through dynamic head-to-tail polymerisation by means of its DIX domain. It thus transduces Wnt signals to cytoplasmic effectors including ß-catenin, to control cell fates during normal development, tissue homeostasis and also in cancer. To date, most functional studies of Dishevelled relied on its Wnt-independent signalling activity resulting from overexpression, which is sufficient to trigger polymerisation, bypassing the requirement for Wnt signals. Here, we generate a human cell line devoid of endogenous Dishevelled (DVL1- DVL3), which lacks Wnt signal transduction to ß-catenin. However, Wnt responses can be restored by DVL2 stably re-expressed at near-endogenous levels. Using this assay to test mutant DVL2, we show that its DEP domain is essential, whereas its PDZ domain is dispensable, for signalling to ß-catenin. Our results imply two mutually exclusive functions of the DEP domain in Wnt signal transduction - binding to Frizzled to recruit Dishevelled to the receptor complex, and dimerising to cross-link DIX domain polymers for signalosome assembly. Our assay avoids the caveats associated with overexpressing Dishevelled, and provides a powerful tool for rigorous functional tests of this pivotal human signalling protein.
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Banco de datos:
MEDLINE
Asunto principal:
Bioensayo
/
Proteína Wnt3A
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Proteínas Dishevelled
Límite:
Humans
Idioma:
En
Revista:
J Cell Sci
Año:
2016
Tipo del documento:
Article