1. Cell Biology
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Pak1 kinase controls cell shape through ribonucleoprotein granules

  1. Joseph O Magliozzi
  2. James B Moseley  Is a corresponding author
  1. The Geisel School of Medicine at Dartmouth, United States
Research Article
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Cite this article as: eLife 2021;10:e67648 doi: 10.7554/eLife.67648

Abstract

Fission yeast cells maintain a rod shape due to conserved signaling pathways that organize the cytoskeleton for polarized growth. We discovered a mechanism linking the conserved protein kinase Pak1 with cell shape through the RNA-binding protein Sts5. Pak1 (also called Shk1 and Orb2) prevents Sts5 association with P bodies by directly phosphorylating its intrinsically disordered region (IDR). Pak1 and the cell polarity kinase Orb6 both phosphorylate the Sts5 IDR but at distinct residues. Mutations preventing phosphorylation in the Sts5 IDR cause increased P body formation and defects in cell shape and polarity. Unexpectedly, when cells encounter glucose starvation, PKA signaling triggers Pak1 recruitment to stress granules with Sts5. Through retargeting experiments, we reveal that Pak1 localizes to stress granules to promote rapid dissolution of Sts5 upon glucose addition. Our work reveals a new role for Pak1 in regulating cell shape through ribonucleoprotein granules during normal and stressed growth conditions.

Data availability

All relevant data are included in the manuscript and supporting files.

Article and author information

Author details

  1. Joseph O Magliozzi

    Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4173-2369
  2. James B Moseley

    Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover, United States
    For correspondence
    james.b.moseley@dartmouth.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7354-7416

Funding

National Institute of General Medical Sciences (R01-GM099774)

  • James B Moseley

National Institute of General Medical Sciences (R01-GM133856)

  • James B Moseley

National Institute of General Medical Sciences (P20-GM113132)

  • Joseph O Magliozzi
  • James B Moseley

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Mohan K Balasubramanian, University of Warwick, United Kingdom

Publication history

  1. Received: February 17, 2021
  2. Accepted: July 19, 2021
  3. Accepted Manuscript published: July 20, 2021 (version 1)

Copyright

© 2021, Magliozzi & Moseley

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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