Sureau C, Guerra B, Lee H
Department of Virology and Immunology, Southwest Foundation for Biomedical Research, San Antonio, Texas 78228.
J Virol. 1994 Jun;68(6):4063-6. doi: 10.1128/JVI.68.6.4063-4066.1994.
The hepatitis delta virus (HDV) envelope contains the large (L), middle (M), and small (S) surface proteins encoded by coinfecting hepatitis B virus. Although HDV-like particles can be assembled with only the S protein in the envelope, the L protein is essential for infectivity in vitro (C. Sureau, B. Guerra, and R. Lanford, J. Virol. 67:366-372, 1993). Here, we demonstrate that the M protein, previously described as carrying a site for binding to polymerized human albumin, is not necessary for infectivity. HDV-like particles coated with the S plus L or the S plus M plus L proteins are infectious in primary cultures of chimpanzee hepatocytes. We conclude that the S and L proteins serve two essential functions in the HDV replication cycle; the S protein ensures the export of the HDV genome from an infected cell by forming a particle, and the L protein ensures its import into a human hepatocyte.
丁型肝炎病毒（HDV）包膜包含由共感染的乙型肝炎病毒编码的大（L）、中（M）和小（S）表面蛋白。虽然仅包膜中的S蛋白就能组装出HDV样颗粒，但L蛋白对体外感染性至关重要（C. 叙雷奥、B. 格拉和R. 兰福德，《病毒学杂志》67:366 - 372，1993年）。在此，我们证明，先前被描述为携带与聚合人白蛋白结合位点的M蛋白对感染性并非必需。包被有S加L或S加M加L蛋白的HDV样颗粒在黑猩猩肝细胞原代培养物中具有感染性。我们得出结论，S蛋白和L蛋白在HDV复制周期中发挥两种重要功能；S蛋白通过形成颗粒确保HDV基因组从受感染细胞中输出，而L蛋白确保其进入人肝细胞。
