Characterization of the Interaction between Latency-Associated Nuclear Antigen and Glycogen Synthase Kinase 3β

The latency-associated nuclear antigen (LANA) of Karposi's sarcoma-associated herpesvirus has been reported to interact with glycogen synthase kinase 3 beta (GSK-3 beta) and regulate its activity, leading to inhibition of GSK-3-dependent beta-catenin degradation. In this study, the interaction between LANA and GSK-3 beta was characterized further. LANA was found to interact with GSK-3 beta in vitro as well as in intact cells. However, LANA did not regulate GSK-3 beta kinase activity and LANA-induced upregulation of beta-catenin was GSK-3 beta independent. LANA did not regulate the stability of beta-catenin or of its reported interaction partners p53 and von Hippel-Lindau protein. Additional targets of LANA are likely to mediate its malignancy-promoting function.