Herrmann C H, Dery C V, Mathews M B
Cold Spring Harbor Laboratory, New York 11724.
Oncogene. 1987;2(1):25-35.
Adenovirus contains two nuclear oncogenes, the EIA and EIB genes, which cooperatively can transform cells through mechanisms that are not understood. The transcriptional activities of the E1A gene (transactivation and repression) are well studied. Using transient expression assays, we show here that the 19,000-Da E1B gene product can also activate all the adenovirus early promoters (E1A, E1B, E2e, E3 and E4) and a cellular heat shock gene promoter (hsp70), but not the adenovirus late promoters (IX, IVa2, MLP and E2L). The effect is greatest under conditions where cell growth is inhibited, and appears to operate at the transcriptional level. Possible interactions with enhancer elements are discussed. Although the E1B stimulatory effect does not require the presence of E1A gene products, a synergistic effect is obtained in the presence of E1A 13S product. This activity of the E1B gene is also observed during virus infection and is likely to have important consequences in lytically infected and transformed cells.
腺病毒含有两个核致癌基因，即E1A和E1B基因，它们可通过尚不明确的机制协同转化细胞。对E1A基因的转录活性（反式激活和阻遏）已有深入研究。在此，我们通过瞬时表达分析表明，19000道尔顿的E1B基因产物也能激活所有腺病毒早期启动子（E1A、E1B、E2e、E3和E4）以及一个细胞热休克基因启动子（hsp70），但不能激活腺病毒晚期启动子（IX、IVa2、主要晚期启动子和E2L）。在细胞生长受抑制的条件下，这种效应最为显著，且似乎在转录水平发挥作用。文中讨论了与增强子元件可能的相互作用。尽管E1B的刺激作用并不需要E1A基因产物的存在，但在有E1A 13S产物时会产生协同效应。在病毒感染过程中也观察到了E1B基因的这种活性，并且这可能在裂解感染和转化细胞中产生重要影响。
