FIG 3.

RORα binds to the heptad repeat and marked box region of E2F1. (A) RORα was coimmunoprecipitated with E2F1 in HEK293 cells. The cells were transfected with RORα and/or E2F1 expression vectors. (B) RORα was coimmunoprecipitated with E2F1 in MDA-MB 231 cells. The cells were transfected with RORα and/or E2F1 expression vectors. (C) Binding of endogenous RORα and E2F1 was detected in S1 cells by coimmunoprecipitation experiments. (D) Binding of GST-tagged RORα to E2F1was detected by in vitro GST pulldown assays. DBD, DBD and hinge domain of RORα; LBD, LBD domain of RORα. The DBD and hinge region interacted with E2F1. (E) Binding of GST-tagged E2F1 to RORα was detected by in vitro GST pulldown assays. Deletion of the heptad repeat and marked box region (amino acid 195 to 317) of E2F1 significantly reduced binding of E2F1 to RORα.