BS69 negatively regulates the canonical NF-κB activation induced by Epstein-Barr virus-derived LMP1

Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) activates NF-kappa B signaling pathways through the two C-terminal regions, CTAR1 and CTAR2. BS69 has previously been shown to be involved in LMP1-induced c-Jun N-terminal kinase activation through CTAR2 by interacting with tumor necrosis factor (TNFR) receptor-associated factor 6. In the present study, our manipulation of BS69 expression clearly indicates that BS69 negatively regulates LMP1-mediated NF-kappa B activation and up-regulates IL-6 mRNA expression and I kappa B degradation. Our immunoprecipitation experiments suggest that BS69 decreases complex formation between LMP1 and TNFR-associated death domain protein (TRADD).