Bblf1 and Maturation of Epstein-Barr Virus

After assembly of the Epstein-Barr virus (EBV) nucleocapsid in the nucleus, the virus enters the cytoplasm and the Golgi apparatus to acquire a layer of tegument proteins and envelopes, respectively, before being released from the cell. Among the proteins involved at this stage of EBV development, BBLF1 likely plays a pivotal role in the trafficking of EBV and an EBV glycoprotein, gp350/220. This study first investigates whether BBLF1 is myristylated and palmitylated, which may be important for targeting BBLF1 to the Golgi apparatus and other organelles. Because BBLF1 contains motifs that are typically present in the proteins recycled from the plasma membrane to the Golgi apparatus, this study will investigate whether BBLF1 is recycled by the retrieval pathway. Meanwhile, the glycoprotein gp350/220 of EBV is present in the viral envelope and an important protein necessary for viral infection of B lymphocytes. Although this protein is abundant in the plasma membrane, because the plasma membrane is not incorporated into the EBV envelope, gp350/220 is likely recycled from the plasma membrane to the Golgi apparatus for EBV envelopment. Since BBLF1 is known to interact with gp350/220, the retrieval of gp350/220 to the Golgi apparatus may depend on BBLF1. Additionally, our research indicates that BBLF1 interacts with a minor capsid protein of EBV, BDLF1. This project will investigate whether this interaction is required for trafficking EBV from the cytoplasm to the Golgi apparatus. The results of this study will significantly enhance understanding of EBV maturation process.

Project ID:PA9706-1122
External Project ID:NSC97-3112-B182-007