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NEDD8 acts as a 'molecular switch' defining the functional selectivity of VHL.

ABSTRACT: The von Hippel-Lindau (VHL) tumour suppressor protein is important in the E3 ubiquitin ligase ECV (Elongin B/C-CUL2-VHL)-mediated destruction of hypoxia-inducible factor and the promotion of fibronectin (FN) extracellular matrix assembly. Although the precise molecular mechanism controlling the selectivity of VHL function remains unknown, a failure in either process is associated with oncogenic progression. Here, we show that VHL performs its FN-associated function independently of the ECV complex, highlighting the autonomy of these pathways. Furthermore, we show that NEDD8, a ubiquitin-like molecule, acts as a 'molecular switch' in which its covalent conjugation to VHL prohibits the engagement of the scaffold component CUL2 and, concomitantly, activates the association with FN. These findings provide the first mechanistic step in defining the functional selectivity of VHL and explain a previously unrecognized function of NEDD8.

SUBMITTER: Russell RC

PROVIDER: S-EPMC2373363 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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NEDD8 acts as a 'molecular switch' defining the functional selectivity of VHL.

Russell Ryan C RC Ohh Michael M

EMBO reports 20080307 5

The von Hippel-Lindau (VHL) tumour suppressor protein is important in the E3 ubiquitin ligase ECV (Elongin B/C-CUL2-VHL)-mediated destruction of hypoxia-inducible factor and the promotion of fibronectin (FN) extracellular matrix assembly. Although the precise molecular mechanism controlling the selectivity of VHL function remains unknown, a failure in either process is associated with oncogenic progression. Here, we show that VHL performs its FN-associated function independently of the ECV compl ...[more]

PMID: 18323857

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