Figure 8.

FRET signaling from AKAR2-AKAP12 fusion protein "biosenses" dynamics of phosphorylated, activated AKAP. Panel A, A431 cells were stably transfected with AKAR2-AKAP12. Cells were put in serum starvation for 12 hrs before the recording. Images were recorded for CFP and YFP in absence and presence of isoproterenol (10 μM) and sampled from time = "0" min until time = 30 min. The sampling of the FRET was confined to two cellular locales: the cell membrane (open red rectangles) and the perinuclear, cytoplasmic regions (open yellow circles). The images shown are representative of a large array of images collected for this purpose. Panel B, the fluorescence densities in cell membrane and perinuclear areas were recorded for CFP and for YFP in absence and presence of beta-adrenergic agonist. The data sets are from many samplings, performed on individual cells, and displayed as a representative fluorescence density scan over time.