Article

Insights into the structure of the CCR4-NOT complex by electron microscopy

European Molecular Biology Laboratory, (EMBL), Heidelberg, Germany.
FEBS letters (Impact Factor: 3.34). 06/2011; 585(14):2182-6. DOI: 10.1016/j.febslet.2011.05.071
Source: PubMed

ABSTRACT The CCR4-NOT complex is a deadenylation complex, which plays a major role for mRNA stability. The complex is conserved from yeast to human and consists of nine proteins NOT1-NOT5, CCR4, CAF1, CAF40 and CAF130. We have successfully isolated the complex using a Protein A tag on NOT1, followed by cross-linking on a glycerol gradient. All components of the complex were identified by mass spectrometry. Electron microscopy of negatively stained particles followed by image reconstruction revealed an L-shaped complex with two arms of similar length. The arms form an accessible cavity, which we think could provide an extensive interface for RNA-deadenylation.

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