Figure 3

Activation of human somatostatin receptor subtype-2 by membrane-displayed somatostatin. A. Fluorescence intensity of yeast strains transformed with membrane-displayed somatostatin plasmids. A series of yeast strains with one of the membrane-displayed ligand plasmids was assayed in the late-log phase using a 96-well fluorescent plate reader. Yeast cells harboring pYS21-sst emitted strong fluorescence. Each data point represents data (mean ± standard error of the mean) of three independent experiments. B. Western blot analysis of a series of membrane-displayed somatostatins. Production of membrane-displayed somatostatin on yeast plasma membranes was confirmed by western blot analysis using anti-FLAG tag antibody. The positions of 8.5 and 12 kDa of size markers are indicated by black bars. C. Fluorescence intensity of yeast strains transformed with plasmids for membrane-displayed somatostatin with alanine substitution. Each data point represents data (mean ± standard error of the mean) of three independent experiments. D. Linker dependency of membrane-displayed somatostatin without FLAG tag upon receptor activation. Fluorescence intensity of yeast strains transformed with plasmids for membrane-displayed somatostatin without FLAG tag. Each data point represents data (mean ± standard error of the mean) of three independent experiments.