FIGURE 6.

In response to PTHR, but not β₂AR, activation, XLαs expression results in sustained cAMP production at the plasma membrane. cAMP response measured by FRET changes from HEK293 cells stably expressing PTHR and transiently expressing a cAMP-biosensor, Epac-CFP/YFP with or without XLαs. Cells transfected with XLαs cDNA were co-transfected with plasmids encoding Gβ₁ and Gγ₂. During the experiment, cells were continuously perfused with a control buffer and stimulated with either 100 nm M-PTH(1–14) or 10 μm isoproterenol (ISO). Data are mean ± S.E. of five independent experiments; cell number, n = 80.