Fig. 5. Reconstitution of DRED binding by expression of TR2 and TR4 in tissue culture cells. (A) TR2 or TR4 expression plasmids were transiently transfected into QT6 quail fibroblasts. Two days after transfection, nuclear extracts were prepared and subjected to EMSA using the ‘epsi proxi’ probe. MEL cell nuclear extract was used as a control. (B) Amino/Flag-epitope-tagged or wild-type TR2 or TR4 expression plasmids were transiently transfected into 293T cells. Two days after transfection, nuclear extracts were prepared and subjected to EMSA with the ‘epsi proxi’ probe. Nuclear extracts were preincubated with anti-Flag monoclonal antibody (+) or not (–), before the addition of the radiolabeled ‘epsi proxi’ probe. The arrows indicate the migration position of authentic DRED.