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Dicer-TRBP complex formation ensures accurate mammalian microRNA biogenesis.

ABSTRACT: RNA-mediated gene silencing in human cells requires the accurate generation of ?22 nt microRNAs (miRNAs) from double-stranded RNA substrates by the endonuclease Dicer. Although the phylogenetically conserved RNA-binding proteins TRBP and PACT are known to contribute to this process, their mode of Dicer binding and their genome-wide effects on miRNA processing have not been determined. We solved the crystal structure of the human Dicer-TRBP interface, revealing the structural basis of the interaction. Interface residues conserved between TRBP and PACT show that the proteins bind to Dicer in a similar manner and by mutual exclusion. Based on the structure, a catalytically active Dicer that cannot bind TRBP or PACT was designed and introduced into Dicer-deficient mammalian cells, revealing selective defects in guide strand selection. These results demonstrate the role of Dicer-associated RNA binding proteins in maintenance of gene silencing fidelity.

SUBMITTER: Wilson RC

PROVIDER: S-EPMC4320653 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Dicer-TRBP complex formation ensures accurate mammalian microRNA biogenesis.

Wilson Ross C RC Tambe Akshay A Kidwell Mary Anne MA Noland Cameron L CL Schneider Catherine P CP Doudna Jennifer A JA

Molecular cell 20141231 3

RNA-mediated gene silencing in human cells requires the accurate generation of ∼22 nt microRNAs (miRNAs) from double-stranded RNA substrates by the endonuclease Dicer. Although the phylogenetically conserved RNA-binding proteins TRBP and PACT are known to contribute to this process, their mode of Dicer binding and their genome-wide effects on miRNA processing have not been determined. We solved the crystal structure of the human Dicer-TRBP interface, revealing the structural basis of the interac ...[more]

PMID: 25557550

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