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PubMed · 16410517

Structural basis for double-stranded RNA processing by Dicer.

Ian J Macrae·Kaihong Zhou·Fei Li·Adrian Repic·Angela N Brooks·W Zacheus Cande·Paul D Adams·Jennifer A Doudna
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Abstract

The specialized ribonuclease Dicer initiates RNA interference by cleaving double-stranded RNA (dsRNA) substrates into small fragments about 25 nucleotides in length. In the crystal structure of an intact Dicer enzyme, the PAZ domain, a module that binds the end of dsRNA, is separated from the two catalytic ribonuclease III (RNase III) domains by a flat, positively charged surface. The 65 angstrom distance between the PAZ and RNase III domains matches the length spanned by 25 base pairs of RNA. Thus, Dicer itself is a molecular ruler that recognizes dsRNA and cleaves a specified distance from the helical end.

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Amino Acid SequenceAnimalsConserved SequenceCrystallography, X-RayGiardia lambliaHumansLanthanoid Series ElementsModels, MolecularMolecular Sequence DataProtein Structure, TertiaryRNA InterferenceRNA, Double-StrandedRNA, ProtozoanRecombinant Fusion ProteinsRibonuclease IIISchizosaccharomycesStructure-Activity RelationshipJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't

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Ian J Macrae, Kaihong Zhou, Fei Li, Adrian Repic, Angela N Brooks, W Zacheus Cande, Paul D Adams, Jennifer A Doudna. 2006-01-13. Structural basis for double-stranded RNA processing by Dicer.. https://doi.org/10.1126/science.1121638

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