LANA physically interacts with c-Jun. (A) The indicated plasmids were transiently transfected into 293 cells, and total protein was extracted at 48 hours for coimmunoprecipitation. The protein from the first 2 lanes is the same. Top panel is coimmunoprecipitation. The arrow indicates a specific LANA band; the arrowhead represents a nonspecific band that is also faintly detected in lanes that were not transfected with 3 × FLAG-LANA. Middle and bottom panels: Western blots with Jun and FLAG antibodies to demonstrate expression of c-Jun and 3 × FLAG-LANA. (B) Same as panel A, but reciprocal coimmunoprecipitation; 2.5 μg of the 3 × FLAG-LANA and the c-Jun expression vectors or appropriate controls were used. (C) Coimmunoprecipitation of LANA/c-Jun in BCBL-1 cells. Nuclear protein was extracted from BCBL-1 or Raji cells and immunoprecipitated with an anti-LANA monoclonal antibody (or Ig control) followed by Western for c-Jun. (D) Same as panel C, but reciprocal coimmunoprecipitation.