Souyri-Caporale M, Tovey M G, Ono K, Jasmin C, Chermann J C
J Gen Virol. 1984 Apr;65 ( Pt 4):831-5. doi: 10.1099/0022-1317-65-4-831.
The polyoxotungstate HPA-23 was found to exert a differential effect on the induction of Epstein-Barr virus early antigen in Raji cells induced with 5-iodo-2'-deoxyuridine (IUdR). Thus, treatment of Raji cells concomitantly with IUdR and HPA-23 inhibited early antigen expression, and the extent of inhibition was proportional to the duration of treatment with HPA-23. In contrast, pretreatment of Raji cells with HPA-23 prior to induction with IUdR stimulated early antigen expression in exponentially multiplying but not in stationary-phase cells. HPA-23 alone had no effect on early antigen expression in Raji cells. Activation of the latent Epstein-Barr virus genome by IUdR is dependent upon incorporation of the thymidine analogue into cellular DNA during the S-phase of the cell cycle. Synthesis of Epstein-Barr virus DNA also takes place during S-phase, suggesting a possible participation in this process of cellular DNA polymerase alpha which is thought to be responsible for cellular DNA replication and the activity of which increases several-fold during S-phase. Treatment of Raji cells with HPA-23 caused a marked decrease in DNA polymerase alpha activity, which could result in an inhibition of IUdR incorporation leading to the observed reduction of early antigen expression in cells treated concomitantly with IUdR and HPA-23.
发现多金属氧酸盐HPA - 23对5 - 碘 - 2'-脱氧尿苷（IUdR）诱导的Raji细胞中Epstein - Barr病毒早期抗原的诱导具有不同的作用。因此，Raji细胞同时用IUdR和HPA - 23处理可抑制早期抗原表达，且抑制程度与HPA - 23的处理持续时间成正比。相比之下，在IUdR诱导之前用HPA - 23预处理Raji细胞，在指数增殖的细胞中刺激早期抗原表达，但在静止期细胞中则不然。单独的HPA - 23对Raji细胞中的早期抗原表达没有影响。IUdR对潜伏的Epstein - Barr病毒基因组的激活取决于在细胞周期的S期将胸苷类似物掺入细胞DNA中。Epstein - Barr病毒DNA的合成也发生在S期，这表明细胞DNA聚合酶α可能参与了这一过程，细胞DNA聚合酶α被认为负责细胞DNA复制，其活性在S期增加几倍。用HPA - 23处理Raji细胞导致DNA聚合酶α活性显著降低，这可能导致IUdR掺入受到抑制，从而导致在同时用IUdR和HPA - 23处理的细胞中观察到早期抗原表达减少。
