Coupling between the DEAD-box RNA helicases Ded1p and eIF4A
- Case Western Reserve University, United States
- University of Richmond, United States
Abstract
Eukaryotic translation initiation involves two conserved DEAD-box RNA helicases, eIF4A and Ded1p. Here we show that S. cerevisiae eIF4A and Ded1p directly interact with each other and simultaneously with the scaffolding protein eIF4G. We delineate a comprehensive thermodynamic framework for the interactions between Ded1p, eIF4A, eIF4G, RNA and ATP, which indicates that eIF4A, with and without eIF4G, acts as modulator for activity and substrate preferences of Ded1p, which is the RNA remodeling unit in all complexes. Our results reveal and characterize an unexpected interdependence between the two RNA helicases and eIF4G, and suggest that Ded1p is an integral part of eIF4F, the complex comprising eIF4G, eIF4A, and eIF4E.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (GM118088)
- Zhaofeng Gao
- Andrea A Putnam
- Heath A Bowers
- Ulf-Peter Guenther
- Xuan Ye
- Eckhard Jankowsky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Gao 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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Coupling between the DEAD-box RNA helicases Ded1p and eIF4A
eLife 5:e16408.
https://doi.org/10.7554/eLife.16408
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