Nevins J R
Cell. 1981 Oct;26(2 Pt 2):213-20. doi: 10.1016/0092-8674(81)90304-4.
Results obtained with certain adenovirus host range mutants (dl312 and hr1) have demonstrated that a functional viral E1A gene is required for the accumulation of early viral mRNA. In this report, it is demonstrated that the failure to accumulate early viral mRNA in E1A mutant-infected cells is due to a lack of transcription of the appropriate transcription units. The E1A gene product appears to enhance transcription of the early transcription units since there is not an absolute requirement for its function. At low multiplicities of infection, transcription from the early transcription units can be detected but at a later time. By increasing the multiplicity of infection, this show activation of early transcription can be enhanced, even though at this multiplicity all input viruses are still mutant. It was also found that early transcription could be detected in mutant-infected cells if the virus was added to cells in which protein synthesis was inhibited prior to infection. Thus inhibition of cellular protein synthesis can mimic the function of the E1A gene. It is proposed that the role of the E1A gene product in the activation of early viral transcription is to inactivate a cellular factor that prevents transcription from the early viral promoters.
用某些腺病毒宿主范围突变体（dl312和hr1）获得的结果表明，功能性病毒E1A基因是早期病毒mRNA积累所必需的。在本报告中，证明了在E1A突变体感染的细胞中未能积累早期病毒mRNA是由于缺乏适当转录单位的转录。E1A基因产物似乎增强了早期转录单位的转录，因为对其功能并非绝对必需。在低感染复数时，可以检测到早期转录单位的转录，但在较晚的时间。通过增加感染复数，这表明早期转录的激活可以增强，即使在这个复数下所有输入病毒仍然是突变体。还发现，如果在感染前将病毒添加到蛋白质合成被抑制的细胞中，则可以在突变体感染的细胞中检测到早期转录。因此，抑制细胞蛋白质合成可以模拟E1A基因的功能。有人提出，E1A基因产物在激活早期病毒转录中的作用是使一种阻止早期病毒启动子转录的细胞因子失活。
