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Design and Profiling of a Subcellular Targeted Optogenetic cAMP-Dependent Protein Kinase.

ABSTRACT: Although the cAMP-dependent protein kinase (PKA) is ubiquitously expressed, it is sequestered at specific subcellular locations throughout the cell, thereby resulting in compartmentalized cellular signaling that triggers site-specific behavioral phenotypes. We developed a three-step engineering strategy to construct an optogenetic PKA (optoPKA) and demonstrated that, upon illumination, optoPKA migrates to specified intracellular sites. Furthermore, we designed intracellular spatially segregated reporters of PKA activity and confirmed that optoPKA phosphorylates these reporters in a light-dependent fashion. Finally, proteomics experiments reveal that light activation of optoPKA results in the phosphorylation of known endogenous PKA substrates as well as potential novel substrates.

SUBMITTER: O'Banion CP

PROVIDER: S-EPMC5777159 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Design and Profiling of a Subcellular Targeted Optogenetic cAMP-Dependent Protein Kinase.

O'Banion Colin P CP Priestman Melanie A MA Hughes Robert M RM Herring Laura E LE Capuzzi Stephen J SJ Lawrence David S DS

Cell chemical biology 20171105 1

Although the cAMP-dependent protein kinase (PKA) is ubiquitously expressed, it is sequestered at specific subcellular locations throughout the cell, thereby resulting in compartmentalized cellular signaling that triggers site-specific behavioral phenotypes. We developed a three-step engineering strategy to construct an optogenetic PKA (optoPKA) and demonstrated that, upon illumination, optoPKA migrates to specified intracellular sites. Furthermore, we designed intracellular spatially segregated ...[more]

PMID: 29104065

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