title: Dual wavelength photoactivation of cAMP- and cGMP-dependent protein kinase signaling pathways.
abstract: The spatial and temporal organization of biological systems offers a level of complexity that is challenging to probe with conventional reagents. Photoactivatable (caged) compounds represent one strategy by which spatiotemporal organizational complexities can be addressed. However, since the vast majority of caged species are triggered by UV light, it is not feasible to orthogonally control two or more spatiotemporal elements of the phenomenon under investigation. For example, the cGMP- and cAMP-dependent protein kinases are highly homologous enzymes, separated in time and space, which mediate the phosphorylation of both distinct and common protein substrates. However, current technology is unable to discriminate, in a temporally or spatially selective fashion, between these enzymes and/or the pathways they influence. We describe herein the intracellular triggering of a cGMP-mediated pathway with 360 nm light and the corresponding cAMP-mediated pathway with 440 nm light. Dual wavelength photoactivation was assessed in A10 cells by monitoring the phosphorylation of vasodilator-stimulated phosphoprotein (VASP), a known substrate for both the cAMP- and cGMP-dependent protein kinases. Illumination at 440 nm elicits a cAMP-dependent phosphorylation of VASP at Ser157, whereas 360 nm exposure triggers the phosphorylation of both Ser157 and Ser239. This is the first example of wavelength-distinct activation of two separate nodes of a common signaling pathway.
authors.affiliation: Department of Chemistry, the Division of Medicinal Chemistry & Natural Products, School of Pharmacy, The University of North Carolina at Chapel Hill, United States.
authors.forename: Melanie A
authors.initials: MA
authors.lastname: Priestman
authors.forename: Liang
authors.initials: L
authors.lastname: Sun
authors.forename: David S
authors.initials: DS
authors.lastname: Lawrence
mesh_terms: D000818:Animals; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism; D017869:Cyclic GMP-Dependent Protein Kinases / Q000378:metabolism*; D005453:Fluorescence; D008027:Light; D008840:Microfilament Proteins / Q000378:metabolism*; D015335:Molecular Probes / Q000032:analysis* / Q000378:metabolism; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D055668:Photochemical Processes / Q000528:radiation effects; D051381:Rats; D012694:Serine / Q000378:metabolism; D015398:Signal Transduction; D013050:Spectrometry, Fluorescence; D000098662:Vasodilator-Stimulated Phosphoprotein
chemical_list: D015815:Cell Adhesion Molecules; D008840:Microfilament Proteins; D015335:Molecular Probes; D010750:Phosphoproteins; D000098662:Vasodilator-Stimulated Phosphoprotein; D012694:Serine; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D017869:Cyclic GMP-Dependent Protein Kinases; D006152:Cyclic GMP