Fluticasone propionate competes with phospho-GATA-3 for importin-α.
(A) schematic representation of the in vitro binding competition assay. (B) GR isolated from FP (10−8 M) stimulated cells enhances GR–importin-α binding in the presence (•) and absence (▪) of activated GATA-3. * p<0.05 compared to no activated GR. (C) GATA-3 isolated from anti-CD3/CD28–stimulated cells does not attenuate GR–importin-α association. *p<0.05 compared to control. (D) Activated GR blocks the ability of purified phospho-GATA-3 isolated from anti-CD3/CD28–stimulated cells interacting with immobilised importin-α in an in vitro binding assay. *p<0.05 compared to GATA-3 isolated from unstimulated cells. #p<0.05 compared to stimulated GATA-3-importin binding. (E) The effect of activated (•) versus unstimulated (○) GR on attenuation of GATA-3–importin-α association was concentration-dependent. *p<0.05, **p<0.01 between groups. All results are expressed as mean±SEM of three independent experiments and analysed by ANOVA followed by Newman-Keuls post-test.
