MCPyV LT-t is not bound or destabilized by Fbw7.

(A) Whole cell lysates of 293A cells transfected with individual or combinations of FLAG-Fbw7 (4.5μg), ΔFbox (3μg), HA-SV40 LT (5μg), MCPyV LT-t (10.5μg), were pulled-down with XT10, and immunoblotted with anti-FLAG. (B) 293A cells were transfected with a constant amount of MCPyV LT-t (10μg) and increasing amounts of Fbw7 (2.5μg, 5μg, 10μg) or the stable, degradation incompetent, Fbw7 ΔFbox (1.25μg, 2.5μg, 5μg). MCPyV LT-t protein levels were compared by 2T2 immunoblotting (common-T antibody). (C) Similar to Fig 3B, 293A cells were transfected with consistent amounts of HA-c-Myc (2μg) and increasing amounts of Fbw7 (0.1μg, 0.25μg, and 0.5μg). c-Myc protein levels were compared through detection of c-Myc by immunoblotting with anti-HA.