1. Cell Biology
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Stress-induced Cdk5 activity enhances cytoprotective basal autophagy in Drosophila melanogaster by phosphorylating acinus at serine437

  1. Nilay Nandi
  2. Lauren K Tyra
  3. Drew Stenesen
  4. Helmut Krämer  Is a corresponding author
  1. University of Texas Southwestern Medical Center, United States
Research Article
  • Cited 9
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Cite this article as: eLife 2017;6:e30760 doi: 10.7554/eLife.30760

Abstract

Cdk5 is a post-mitotic kinase with complex roles in maintaining neuronal health. The various mechanisms by which Cdk5 inhibits and promotes neurodegeneration are still poorly understood. Here, we show that in Drosophila melanogaster Cdk5 regulates basal autophagy, a key mechanism suppressing neurodegeneration. In a targeted screen, Cdk5 genetically interacted with Acinus (Acn), a primarily nuclear protein, which promotes starvation-independent, basal autophagy. Loss of Cdk5, or its required cofactor p35, reduces S437-Acn phosphorylation, whereas Cdk5 gain-of-function increases pS437-Acn levels. The phospho-mimetic S437D mutation stabilizes Acn and promotes basal autophagy. In p35 mutants, basal autophagy and lifespan are reduced, but restored to near wild-type levels in the presence of stabilized AcnS437D. Expression of aggregation-prone polyQ-containing proteins or the Amyloid-b42 peptide, but not alpha-Synuclein, enhances Cdk5-dependent phosphorylation of S437-Acn. Our data indicate that Cdk5 is required to maintain the protective role of basal autophagy in the initial responses to a subset of neurodegenerative challenges.

Article and author information

Author details

  1. Nilay Nandi

    Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Lauren K Tyra

    Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Drew Stenesen

    Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Helmut Krämer

    Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    helmut.kramer@utsouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1167-2676

Funding

National Eye Institute (EY010199)

  • Helmut Krämer

National Science Foundation (4900835401-36068)

  • Lauren K Tyra

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

Reviewing Editor

  1. Hong Zhang, Institute of Biophysics, Chinese Academy of Sciences, China

Publication history

  1. Received: July 26, 2017
  2. Accepted: December 8, 2017
  3. Accepted Manuscript published: December 11, 2017 (version 1)
  4. Version of Record published: January 9, 2018 (version 2)

Copyright

© 2017, Nandi 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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