Kenney S, Holley-Guthrie E, Mar E C, Smith M
Department of Medicine, University of North Carolina, Chapel Hill 27514.
J Virol. 1989 Sep;63(9):3878-83. doi: 10.1128/JVI.63.9.3878-3883.1989.
We have previously shown that the Epstein-Barr virus (EBV) immediate-early gene product, BZLF1, can activate expression of the EBV BMLF1 immediate-early promoter in EBV-positive, but not EBV-negative, B cells, suggesting that the BZLF1 effect may be mediated through another EBV gene product (S. Kenney, J. Kamine, E. Holley-Guthrie, J.-C. Lin, E.-C. Mar, and J. S. Pagano, J. Virol. 63:1729-1736, 1989). Here, we show that the EBV BRLF1 immediate-early gene product transactivates the BMLF1 promoter in either EBV-positive or EBV-negative B cells. Deletional analysis revealed that both the BZLF1-responsive region and the BRLF1-responsive region of the BMLF1 promoter are contained within the same 140-base-pair FokI-PvuII fragment located 300 base pairs upstream of the mRNA start site. This FokI-PvuII fragment functions as an enhancer element in the presence of the BRLF1 transactivator and contains the sequence CCGTGGAGA ATGTC, which is strikingly similar to the BRLF1-responsive region of the EBV DR/DL enhancer (A. Chevallier-Greco, H. Gruffat, E. Manet, A. Calender, and A. Sergeant, J. Virol. 63:615-623, 1989). The effect of BZLF1 on the BMLF1 promoter is likely to be indirect and mediated through the BRLF1 transactivator.
我们先前已表明，爱泼斯坦-巴尔病毒（EBV）即刻早期基因产物BZLF1可激活EBV阳性而非EBV阴性B细胞中EBV BMLF1即刻早期启动子的表达，这表明BZLF1的作用可能是通过另一种EBV基因产物介导的（S. 肯尼、J. 卡米内、E. 霍利-古思里、J.-C. 林、E.-C. 马尔和J. S. 帕加诺，《病毒学杂志》63:1729 - 1736, 1989）。在此，我们表明EBV BRLF1即刻早期基因产物可在EBV阳性或EBV阴性B细胞中转录激活BMLF1启动子。缺失分析显示，BMLF1启动子的BZLF1反应区域和BRLF1反应区域均包含在位于mRNA起始位点上游300个碱基对处的同一个140碱基对的FokI - PvuII片段内。在存在BRLF1反式激活因子的情况下，这个FokI - PvuII片段作为增强子元件发挥作用，并且包含序列CCGTGGAGA ATGTC，该序列与EBV DR/DL增强子的BRLF1反应区域惊人地相似（A. 谢瓦利耶 - 格雷科、H. 格鲁法特、E. 马内、A. 卡伦德和A. 塞尔让，《病毒学杂志》63:615 - 623, 1989）。BZLF1对BMLF1启动子的作用可能是间接的，并通过BRLF1反式激活因子介导。
