Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brain
- University of California, San Diego, United States
- The Salk Institute for Biological Studies, United States
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.
Data availability
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Data from: Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brainPublicly available at the Cell Centered Database (CIL:49451).
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Data from: Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brainPublicly available at the Cell Centered Database (CIL:49651).
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Data from: Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brainPublicly available at the Cell Centered Database (CIL:49453).
Article and author information
Author details
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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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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