1. Cell Biology
  2. Neuroscience

Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brain

  1. Ronit Ilouz  Is a corresponding author
  2. Varda Lev-Ram
  3. Eric A Bushong
  4. Travis L Stiles
  5. Dinorah Friedmann-Morvinski
  6. Christopher Douglas
  7. Geoffrey Goldberg
  8. Mark H Ellisman
  9. Susan S Taylor  Is a corresponding author
  1. University of California, San Diego, United States
  2. The Salk Institute for Biological Studies, United States
https://doi.org/10.7554/eLife.17681
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Cite this article
  1. Ronit Ilouz
  2. Varda Lev-Ram
  3. Eric A Bushong
  4. Travis L Stiles
  5. Dinorah Friedmann-Morvinski
  6. Christopher Douglas
  7. Geoffrey Goldberg
  8. Mark H Ellisman
  9. Susan S Taylor
(2017)
Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brain
eLife 6:e17681.
https://doi.org/10.7554/eLife.17681
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Abstract

Protein kinase A (PKA) plays critical roles in neuronal function that are mediated by different regulatory (R) subunits. Deficiency in either RIβ or RIIβ subunits results in distinct neuronal phenotypes. Although RIβ contributes to synaptic plasticity, it is the least studied isoform. Using isoform-specific antibodies we generated high-resolution large-scale immunohistochemical mosaic images of mouse brain that provide global views of several brain regions, including the hippocampus and cerebellum. The isoforms concentrate in discrete brain regions and we then zoom-in to show distinct patterns of subcellular localization. RIβ is enriched in dendrites and co-localizes with MAP2, whereas RIIβ is concentrated in axons. Using correlated light and electron microscopy we confirm mitochondrial and nuclear localization of RIβ in cultured neurons. To show the functional significance of nuclear localization, we demonstrate that down-regulation of RIβ, but not RIIβ, decreased CREB phosphorylation. Our study reveals how PKA isoform specificity is defined by precise localization.

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Author details

  1. Ronit Ilouz

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    For correspondence
    rilouz@ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.

  2. Varda Lev-Ram

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Eric A Bushong

    Center for Research in Biological Systems, University of California, San Diego, San Diego, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6195-2433

  4. Travis L Stiles

    Department of Ophthalmology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Dinorah Friedmann-Morvinski

    Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.

  6. Christopher Douglas

    Department of Ophthalmology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. Geoffrey Goldberg

    Department of Ophthalmology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.

  8. Mark H Ellisman

    Center for Research in Biological Systems, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.

  9. Susan S Taylor

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    For correspondence
    staylor@ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7702-6108

Funding

National Institute of Diabetes and Digestive and Kidney Diseases (DK054441)

  • Susan S Taylor

National Institute of General Medical Sciences (P41GM103412)

  • Mark H Ellisman

National Institute of General Medical Sciences (GM082949)

  • Mark H Ellisman

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

Ethics

Animal experimentation: All experiments involving vertebrate animals conform to the National Institute of Health Guide for the Care and Use of Laboratory Animals (NIH publication 865-23, Bethesda, MD, USA) and were approved by the Institutional Animal Care and Use Committee (IACUC) of the University of California San Diego. Approved Animal Protocol Numbers: S03172m, S03182R.

Copyright

© 2017, Ilouz 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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  1. Ronit Ilouz
  2. Varda Lev-Ram
  3. Eric A Bushong
  4. Travis L Stiles
  5. Dinorah Friedmann-Morvinski
  6. Christopher Douglas
  7. Geoffrey Goldberg
  8. Mark H Ellisman
  9. Susan S Taylor
(2017)
Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brain
eLife 6:e17681.
https://doi.org/10.7554/eLife.17681

Share this article

https://doi.org/10.7554/eLife.17681

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