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Architecture of the ubiquitylation module of the yeast Ccr4-Not complex.

ABSTRACT: The Ccr4-Not complex regulates eukaryotic gene expression at multiple levels, including mRNA turnover, translational repression, and transcription. We have studied the ubiquitylation module of the yeast Ccr4-Not complex and addressed how E3 ligase binds cognate E2 and how it is tethered to the complex. The 2.8-Å resolution crystal structure of the N-terminal RING domain of Not4 in complex with Ubc4 shows the detailed interactions of this E3-E2 complex. The 3.6-Å resolution crystal structure of the C-terminal domain of the yeast Not4 in complex with the C-terminal domain of Not1 reveals how a largely extended region at the C-terminus of Not4 wraps around a HEAT-repeat region of Not1. This C-terminal region of Not4 is only partly conserved in metazoans, rationalizing its weaker Not1-binding properties. The structural and biochemical data show how Not1 can incorporate both the ubiquitylation module and the Not2-Not3/5 module concomitantly in the Ccr4-Not complex.

SUBMITTER: Bhaskar V

PROVIDER: S-EPMC4431670 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Architecture of the ubiquitylation module of the yeast Ccr4-Not complex.

Bhaskar Varun V Basquin Jérôme J Conti Elena E

Structure (London, England : 1993) 20150423 5

The Ccr4-Not complex regulates eukaryotic gene expression at multiple levels, including mRNA turnover, translational repression, and transcription. We have studied the ubiquitylation module of the yeast Ccr4-Not complex and addressed how E3 ligase binds cognate E2 and how it is tethered to the complex. The 2.8-Å resolution crystal structure of the N-terminal RING domain of Not4 in complex with Ubc4 shows the detailed interactions of this E3-E2 complex. The 3.6-Å resolution crystal structure of t ...[more]

PMID: 25914052

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