Latent Membrane Protein 1 (LMP1)

Latent membrane protein 1 (LMP1), which is critical for EBV-induced B-cell transformation, is also abundantly expressed during the lytic cycle of viral replication. Akata cell clones harboring the episomes of LMP1-deleted EBV were established, and the effect of LMP1 loss on virus production was investigated. Nucleocapsid formation inside nuclei occurred even in the absence of LMP1. By contrast, loss of LMP1 severely impaired virus release into culture supernatants, resulting in poor infection efficiency. The expression of truncated LMP1 in Akata cells harboring LMP1-deleted EBV rescued the virus release into the culture supernatant and the infectivity, and full-length LMP1 partially rescued the infectivity. These results indicate that inducible expression of LMP1 during the viral lytic cycle plays a critical role in virus production.