title: Isoform-specific subcellular localization and function of protein kinase A identified by mosaic imaging of mouse brain.
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.
authors.affiliation: Department of Pharmacology, University of California, San Diego, La Jolla, United States.
authors.forename: Ronit
authors.initials: R
authors.lastname: Ilouz
authors.affiliation: Department of Pharmacology, University of California, San Diego, La Jolla, United States.
authors.forename: Varda
authors.initials: V
authors.lastname: Lev-Ram
authors.affiliation: Center for Research in Biological Systems, National Center for Microscopy and Imaging Research, University of California, San Diego, San Diego, United States.
authors.forename: Eric A
authors.identifier: 0000-0001-6195-2433
authors.initials: EA
authors.lastname: Bushong
authors.affiliation: Department of Ophthalmology, Shiley Eye Center, University of California, San Diego, La Jolla, United States.
authors.forename: Travis L
authors.initials: TL
authors.lastname: Stiles
authors.affiliation: Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, United States.|Department of Biochemistry and Molecular Biology, George S Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Dinorah
authors.initials: D
authors.lastname: Friedmann-Morvinski
authors.affiliation: Department of Ophthalmology, Shiley Eye Center, University of California, San Diego, La Jolla, United States.
authors.forename: Christopher
authors.initials: C
authors.lastname: Douglas
authors.affiliation: Department of Ophthalmology, Shiley Eye Center, University of California, San Diego, La Jolla, United States.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Goldberg
authors.affiliation: Center for Research in Biological Systems, National Center for Microscopy and Imaging Research, University of California, San Diego, San Diego, United States.|Department of Neurosciences, University of California, San Diego School of Medicine, La Jolla, United States.
authors.forename: Mark H
authors.initials: MH
authors.lastname: Ellisman
authors.affiliation: Department of Pharmacology, University of California, San Diego, La Jolla, United States.|Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, United States.
authors.forename: Susan S
authors.identifier: 0000-0002-7702-6108
authors.initials: SS
authors.lastname: Taylor
mesh_terms: D000818:Animals; D001369:Axons / Q000737:chemistry; D001923:Brain Chemistry; D017868:Cyclic AMP-Dependent Protein Kinases / Q000032:analysis*; D003712:Dendrites / Q000737:chemistry; D007150:Immunohistochemistry; D051379:Mice; D020033:Protein Isoforms / Q000032:analysis*
chemical_list: D020033:Protein Isoforms; D017868:Cyclic AMP-Dependent Protein Kinases
keywords: High resolution large scale images; Immunohistochemical mouse brain images; PKA regulatory subunits; cell biology; cellular and subcellular localization; correlated light and electron microscopy; mouse; neuroscience; protein kinases; rat