Spatial control of translation repression and polarized growth by conserved NDR kinase Orb6 and RNA-binding protein Sts5
- University of Miami School of Medicine, United States
- The University of Tennessee, United States
- National Research Institute of Brewing, Japan
- Hiroshima University, Japan
- The Francis Crick Institute, United Kingdom
Abstract
RNA-binding proteins contribute to the formation of ribonucleoprotein (RNP) granules by phase transition, but regulatory mechanisms are not fully understood. Conserved fission yeast NDR (Nuclear Dbf2-Related) kinase Orb6 governs cell morphogenesis in part by spatially controlling Cdc42 GTPase. Here we describe a novel, independent function for Orb6 kinase in negatively regulating the recruitment of RNA-binding protein Sts5 into RNPs to promote polarized cell growth. We find that Orb6 kinase inhibits Sts5 recruitment into granules, its association with processing (P) bodies, and degradation of Sts5-bound mRNAs by promoting Sts5 interaction with 14-3-3 protein Rad24. Many Sts5-bound mRNAs encode essential factors for polarized cell growth, and Orb6 kinase spatially and temporally controls the extent of Sts5 granule formation. Disruption of this control system affects cell morphology and alters the pattern of polarized cell growth, revealing a role for Orb6 kinase in the spatial control of translational repression that enables normal cell morphogenesis.
Article and author information
Author details
Funding
National Institutes of Health (GM095867)
- Marbelys Rodriguez Pino
- David J Wiley
- Maitreyi E Das
- Chuan Chen
- Fulvia Verde
National Science Foundation (745129)
- Maitreyi E Das
- Fulvia Verde
Cancer Research UK
- Takashi Toda
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- J Paul Taylor, St Jude Children's Research Hospital, United States
Version history
- Received: January 8, 2016
- Accepted: July 28, 2016
- Accepted Manuscript published: July 30, 2016 (version 1)
- Version of Record published: September 5, 2016 (version 2)
Copyright
© 2016, Nuñez 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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Spatial control of translation repression and polarized growth by conserved NDR kinase Orb6 and RNA-binding protein Sts5
eLife 5:e14216.
https://doi.org/10.7554/eLife.14216
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