Structural insights into the mechanism of the DEAH-box RNA helicase Prp43
- Georg-August-University Göttingen, Germany
- Max Planck Institute for Biophysical Chemistry, Germany
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 β-turn of the RecA1 domain containing the newly identified RF motif. This mechanism is clearly different to those of other RNA helicases.
Data availability
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Crystal structure of the Prp43-ADP-BeF3-U7-RNA complexPublicly available at the RCSB Protein Data Bank (accession no: 5LTA).
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Crystal structure of the Prp43-ADP-BeF3 complex (in orthorhombic space group)Publicly available at the RCSB Protein Data Bank (accession no: 5ltj).
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Crystal structure of the Prp43-ADP-BeF3 complex (in hexagonal space group)Publicly available at the RCSB Protein Data Bank (accession no: 5LTK).
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Crystal structure of the RNA-helicase Prp43 from Chaetomium thermophilum bound to ADPPublicly available at the RCSB Protein Data Bank (accession no: 5D0U).
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Structure of MLE RNA ADP AlF4 complexPublicly available at the RCSB Protein Data Bank (accession no: 5AOR).
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Visualizing ATP-dependent RNA Translocation by the NS3 Helicase from HCVPublicly available at the RCSB Protein Data Bank (accession no: 3O8R).
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft ((SFB860 TPA2))
- Ralf Ficner
Deutsche Forschungsgemeinschaft ((SFB860 TPA1))
- Reinhard Lührmann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Tauchert et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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