Figure 4.

AR interacts with KIF5B. A, co-immunoprecipitation (co-IP) of KIF5B-tail or KIFC3-tail with AR. COS-7 cells were co-transfected with Myc-tagged KIF5B-tail or KIFC3-tail with AR. Co-IP assays were performed with an antibody against Myc-tag, followed by immunoblot with antibodies against AR and Myc-tag. Input, cell lysates were analyzed for the expression of AR and KIF5B-tail or KIFC3-tail. A control co-IP experiment was performed with a mouse IgG. B, the endogenous AR-KIF5B interaction. LNCaP cells were treated with EtOH or R1881 20 min, and a reciprocal co-IP assay was performed with an antibody against AR, followed by Western blot analyses for AR and KIF5B. C, In vitro pulldown assay for AR. Myc-tagged KIF5B-tail or KIFC3-tail was expressed in COS-7 cells, and enriched by protein G magnetic beads coated with an anti-Myc-tag antibody. The magnetic beads were subsequently incubated with lysates from COS-7 cells transfected with AR, and the eluted proteins were analyzed by immunoblotting. D, the KIF5B-tail–AR interaction is enhanced by androgen. COS-7 cells co-transfected with KIF5B-tail and AR were cultured in RPMI 1640 supplemented with 10% cs-FBS, and treated with EtOH or R1881 for 20 min. The lysates were analyzed by the co-IP assay.