Fig. 6

PACmn activates PKA when illuminated without altering basal activity in hippocampal neurons. A Resting FRET ratios (soma) in hippocampal neurons expressing Booster-PKA alone or together with bPAC variants. Note that only PACmn does not change resting PKA activity. Shown are median and interquartile range. ***p < 0.0001, ns = not significant, Dunnett’s multiple comparisons vs sensor only following one-way ANOVA (p < 0.0001). n = 52, 43, 31, 29, and 18 somata. B Representative ratio images (mKate2/mKoκ) of the hippocampal neurons (soma and dendrite with spines) expressing BoosterPKA before and after foskolin (FSK). C PKA activity in Booster-PKA expressing hippocampal neurons. Bar indicates time of FSK application. D, E Representative ratio images (mKate2/mKoκ) of hippocampal neurons expressing Booster-PKA together with bPAC(wt) (D) or PACmn (E) before and after being illuminated for 2 s with 1 mW mm^-2 470-nm blue light. F PKA activity in Booster-PKA neurons co-expressing bPAC(wt) or PACmn. Arrow indicates a 2 s blue light pulse. In both C and F, the solid lines are from the soma, dashed lines from the dendrites and spines. n (somata): 10 (Booster-PKA), 7 (+bPAC(wt)), 11 (+PACmn); n (dendrites and spines): 10 (Booster-PKA), 18 (+bPAC(wt)), and 14 (+PACmn). Shading indicates SEM. Results presented in A are from experiments done using a different microscope; thus, the difference in resting ratios in comparison to C and F