Fig. 5: Plasma membrane and the Golgi pool of PKA have distinct functions.
From: Cardiac contraction and relaxation are regulated by distinct subcellular cAMP pools
a, Model of targeting a dnPKA to the plasma membrane (PM-dnPKA) to locally regulate PKA activity in neonatal cardiomyocytes. PM-dnPKA was generated by fusing dnPKA with GFP and CAAX motif. b, PM-dnPKA, visualized by GFP (green), was costained with α-actinin (red), a marker of sarcomeric z-disk, and DAPI. Insets show PM-dnPKA and α-`actinin colocalization. n = 24, 3 biological replicates. Scale bar = 10 μm. c, The representative western blots of RyR2, TnI and PLB phosphorylation profiles regulated by epinephrine in the absence or presence of PM-dnPKA expression. The protein levels of pRyR2 Ser2808, pTnI Ser23/Ser24 and pPLB Ser16/Thr17 were analyzed in WT and PM-dnPKA-expressing moue neonatal cardiomyocytes without or with 0.1 μM epinephrine treatment for 15 min. d–f, The band intensities of pRyR2, pTnI and pPLB were normalized with CSQ2 intensity and then reported as a percentage of the highest value in the groups. The quantified data from different experiments were presented as mean ± s.e.m. The P values were calculated by two-way ANOVA. n = 6 biological replicates.
