ATPase activity of the DEAD-box protein Dhh1 controls processing body formation
Abstract
Translational repression and mRNA degradation are critical mechanisms of posttranscriptional gene regulation that help cells respond to internal and external cues. In response to certain stress conditions, many mRNA decay factors are enriched in processing bodies (PBs), cellular structures involved in degradation and/or storage of mRNAs. Yet, how cells regulate assembly and disassembly of PBs remains poorly understood. Here, we show that in budding yeast, mutations in the DEAD-box ATPase Dhh1 that prevent ATP hydrolysis, or that affect the interaction between Dhh1 and Not1, the central scaffold of the Ccr4-NOT complex and an activator of the Dhh1 ATPase, prevent PB disassembly in vivo. Intriguingly, this process can be recapitulated in vitro, since recombinant Dhh1 and RNA, in the presence of ATP, phase-separate into liquid droplets that rapidly dissolve upon addition of Not1. Our results identify the ATPase activity of Dhh1 as a critical regulator of PB formation.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R01GM058065)
- Karsten Weis
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (SNF-159731)
- Karsten Weis
National Institute of General Medical Sciences (R01GM101257)
- Karsten Weis
Human Frontier Science Program (LT000914/2015)
- Maria Hondele
European Molecular Biology Organization (ALTF 290-2014)
- Stephanie Heinrich
Damon Runyon Cancer Research Foundation
- Leon Y Chan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Alan G Hinnebusch, National Institute of Child Health and Human Development, United States
Version history
- Received: June 13, 2016
- Accepted: September 28, 2016
- Accepted Manuscript published: October 3, 2016 (version 1)
- Version of Record published: November 4, 2016 (version 2)
Copyright
© 2016, Mugler 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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