Mandl C W, Frisque R J
J Gen Virol. 1986 Aug;67 ( Pt 8):1733-9. doi: 10.1099/0022-1317-67-8-1733.
One unique feature of the prototype JC virus (JCV) (Mad 1) genome is the occurrence of a second TATA sequence within the early promoter region. A naturally occurring oncogenic variant of JCV (Mad 4) lacks this second TATA box. Several cell lines transformed by Mad 1, Mad 4 and simian virus 40 were characterized, in part to investigate whether the second TATA sequence is functional. S1 nuclease mapping of early JCV gene transcription products revealed a major set of start sites common to both Mad 1 and Mad 4 mRNAs. In addition, a second set of early transcripts was found exclusively in Mad 1 transformants, presumably positioned by the second TATA box. The presence of these unique mRNAs in the Mad 1-transformed cells did not appear to have any bearing on the other parameters investigated, including size and quantity of early viral proteins, integration patterns of viral DNA and growth properties of the cells.
原型JC病毒（JCV）（Mad 1）基因组的一个独特特征是在早期启动子区域出现了第二个TATA序列。JCV的一种自然发生的致癌变体（Mad 4）缺乏这个第二个TATA框。对由Mad 1、Mad 4和猴病毒40转化的几种细胞系进行了表征，部分目的是研究第二个TATA序列是否具有功能。对早期JCV基因转录产物进行S1核酸酶图谱分析，结果显示Mad 1和Mad 4 mRNA共有一组主要的起始位点。此外，还在Mad 1转化体中专门发现了第二组早期转录本，推测是由第二个TATA框定位的。Mad 1转化细胞中这些独特mRNA的存在似乎与所研究的其他参数无关，这些参数包括早期病毒蛋白的大小和数量、病毒DNA的整合模式以及细胞的生长特性。
