FIGURE 4.

Activation of modern and ancestral corticosteroid receptors by synthetic glucocorticoids. A, corticoid receptor phylogeny with response to synthetic glucocorticoids (dexamethasone (Dex)/MOF) is shown. Full agonism is shown in green, and weak or no agonism is shown in red. Human GR (hGR) and MR (hMR) were used to represent extant mammalian GR and MR. The -fold activation (B) and potency (C) of corticosteroid receptor ligand-binding domains were measured via Dual-Luciferase reporter gene activation in transiently transfected CHO-K1 cells. The mean ± S.E. is shown (n = 3). For the purpose of this research, activation below 10-fold over the control (B, red line) was considered weak agonism/antagonism, whereas activation above this threshold was considered full agonism.