Structure of the C-terminus of the mRNA export factor Dbp5 reveals the interaction surface for the ATPase activator Gle1
- 22 September 2009
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 106 (38), 16251-16256
- https://doi.org/10.1073/pnas.0902251106
Abstract
The DExD/H-box RNA-dependent ATPase Dbp5 plays an essential role in the nuclear export of mRNA. Dbp5 localizes to the nuclear pore complex, where its ATPase activity is stimulated by Gle1 and its coactivator inositol hexakisphosphate. Here, we present the crystal structure of the C-terminal domain of Dbp5, refined to 1.8 Å. The structure reveals a RecA-like fold that contains two defining characteristics not present in other structurally characterized DExD/H-box proteins: a C-terminal α-helix and a loop connecting β5 and α4, both of which are composed of conserved and unique elements in the Dbp5 primary sequence. Using structure-guided mutagenesis, we have identified several charged surface residues that, when mutated, weaken the binding of Gle1 and inhibit the ability of Gle1 to stimulate Dbp5's ATPase activity. In vivo analysis of the same mutations reveals that those mutants displaying the weakest ATPase stimulation in vitro are also unable to support yeast growth. Analysis of the correlation between the in vitro and in vivo data indicates that a threshold level of Dbp5 ATPase activity is required for cellular mRNA export that is not met by the unstimulated enzyme, suggesting a possible mechanism by which Dbp5's activity can be modulated to regulate mRNA export.Keywords
This publication has 40 references indexed in Scilit:
- Solution and Crystal Structures of mRNA Exporter Dbp5p and Its Interaction with NucleotidesJournal of Molecular Biology, 2009
- The DEXD/H-box RNA Helicase DDX19 Is Regulated by an α-Helical SwitchJournal of Biological Chemistry, 2009
- Structural and functional analysis of the interaction between the nucleoporin Nup214 and the DEAD-box helicase Ddx19Proceedings of the National Academy of Sciences of the United States of America, 2009
- The mRNA export protein DBP5 binds RNA and the cytoplasmic nucleoporin NUP214 in a mutually exclusive mannerNature Structural & Molecular Biology, 2009
- The mRNA Export Factor Gle1 and Inositol Hexakisphosphate Regulate Distinct Stages of TranslationCell, 2008
- Crystal structure of the yeast eIF4A-eIF4G complex: An RNA-helicase controlled by protein–protein interactionsProceedings of the National Academy of Sciences of the United States of America, 2008
- Regulation of mRNP dynamics along the export pathwayFEBS Letters, 2008
- The DEAD-Box Protein Dbp5 Controls mRNA Export by Triggering Specific RNA:Protein Remodeling EventsMolecular Cell, 2007
- The DEAD-box protein family of RNA helicasesGene, 2005
- Structural basis for the enhancement of eIF4A helicase activity by eIF4GGenes & Development, 2005