Katz R A, Terry R W, Skalka A M
J Virol. 1986 Jul;59(1):163-7. doi: 10.1128/JVI.59.1.163-167.1986.
The deletion of a conserved sequence of ca. 30 nucleotides in the 5' noncoding leader region of an avian sarcoma virus DNA clone resulted in a loss of infectivity after transfection of chicken embryo fibroblasts. Genetic and biochemical analysis of a representative mutant demonstrated that the env gene was expressed normally. Thus, viral RNA transcription, splicing, and translation were not impaired. The amount of mutant viral RNA encapsidated into virions, however, was severely reduced despite the presence of helper-virus. We conclude that the deleted sequence is an essential cis-acting packaging signal.
禽肉瘤病毒DNA克隆5'非编码前导区中约30个核苷酸的保守序列缺失，导致转染鸡胚成纤维细胞后感染性丧失。对一个代表性突变体的遗传和生化分析表明，env基因正常表达。因此，病毒RNA转录、剪接和翻译均未受损。然而，尽管存在辅助病毒，包装到病毒粒子中的突变病毒RNA量却严重减少。我们得出结论，缺失的序列是一个必需的顺式作用包装信号。
