Abstract
Protein kinase A (PKA) plays critical roles in neuronal function that are mediated by different regulatory (R) subunits. Deficiency in either the RIβ or the RIIβ subunit 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 provided global views of several brain regions, including the hippocampus and cerebellum. The isoforms concentrate in discrete brain regions, and we were able to 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 confirmed the mitochondrial and nuclear localization of RIβ in cultured neurons. To show the functional significance of nuclear localization, we demonstrated that downregulation of RIβ, but not of RIIβ, decreased CREB phosphorylation. Our study reveals how PKA isoform specificity is defined by precise localization.
| Original language | English |
|---|---|
| Article number | e17681 |
| Journal | eLife |
| Volume | 6 |
| DOIs | |
| State | Published - 12 Jan 2017 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© Ilouz et al.
Funding
We thank Dr Maryann Martone from the National Center for Microscopy and Imaging Research (NCMIR) for valuable discussions and critical comments on the manuscript. We thank MHE labora- tory members at NCMIR for helpful discussion, especially Dr Tom Deerinck and Dr Angela Cone (NCMIR). We thank Hiro Hakozaki (NCMIR) for technical support. We thank Dr Harvey Karten, UCSD, for valuable discussions on the manuscript. We are particularly grateful to Dr Davide Dulcis for critical comments on the manuscript. We thank all members of the SST lab, especially: Dr Yuliang Ma for plasmids and valuable discussions, and Dr Kristofer J Haushalter for antibody-specificity immunoblots. We thank Dr Ayelet Gonen for helping with statistical analysis. This work was supported by National Institute of Health Grants DK054441 (to SST). This work was supported by grants from the NIH National Institute of General Medicine Sciences under award number P41GM103412 to Mark Ellisman, which funds the National Center for Microscopy and Imaging Research, and through award number 2 R01 GM082949 to Mark H Ellisman, which funds the Cell Image Library/ Cell Centered Database.
| Funders | Funder number |
|---|---|
| National Institutes of Health | DK054441 |
| National Institute of General Medical Sciences | R01GM082949, P41GM103412 |
| Ministry of Higher Education, Egypt |