Fig. 1.

Basal cAMP production of TSHRs harboring mutations in the allosteric ligand binding site. HEK 293 cells were transiently transfected with wt TSHR and mutated TSHRs. cAMP production was measured by RIA as described in Materials and methods. The basal activity of wt TSHR was set at 1 and the basal activity of the mutants is expressed as fold of wt TSHR. Data are given as mean ± SD of at least two independent experiments, each carried out in duplicate