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Structural insights into the mechanism of the DEAH-box RNA helicase Prp43.

ABSTRACT: The DEAH-box helicase Prp43 is a key player in pre-mRNA splicing as well as the maturation of rRNAs. The exact modus operandi of Prp43 and of all other spliceosomal DEAH-box RNA helicases is still elusive. Here, we report crystal structures of Prp43 complexes in different functional states and the analysis of structure-based mutants providing insights into the unwinding and loading mechanism of RNAs. The Prp43•ATP-analog•RNA complex shows the localization of the RNA inside a tunnel formed by the two RecA-like and C-terminal domains. In the ATP-bound state this tunnel can be transformed into a groove prone for RNA binding by large rearrangements of the C-terminal domains. Several conformational changes between the ATP- and ADP-bound states explain the coupling of ATP hydrolysis to RNA translocation, mainly mediated by a ?-turn of the RecA1 domain containing the newly identified RF motif. This mechanism is clearly different to those of other RNA helicases.

SUBMITTER: Tauchert MJ

PROVIDER: S-EPMC5262380 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Structural insights into the mechanism of the DEAH-box RNA helicase Prp43.

Tauchert Marcel J MJ Fourmann Jean-Baptiste JB Lührmann Reinhard R Ficner Ralf R

eLife 20170116

The DEAH-box helicase Prp43 is a key player in pre-mRNA splicing as well as the maturation of rRNAs. The exact <i>modus operandi</i> of Prp43 and of all other spliceosomal DEAH-box RNA helicases is still elusive. Here, we report crystal structures of Prp43 complexes in different functional states and the analysis of structure-based mutants providing insights into the unwinding and loading mechanism of RNAs. The Prp43•ATP-analog•RNA complex shows the localization of the RNA inside a tunnel formed ...[more]

PMID: 28092261

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