Ogawa T, Hori T, Ishida I
Central Laboratories for Key Technology, Kanagawa, Japan.
Nat Biotechnol. 1996 Nov;14(11):1566-9. doi: 10.1038/nbt1196-1566.
The major components of the 2-5A system, responsible for the mammalian interferon-induced antiviral response, are the 2',5' oligoadenylate synthetase (2-5Aase) and 2',5' oligoadenylate (2-5A) dependent ribonuclease (RNase L). Transgenic tobacco plants expressing these two enzyme activities were produced by crossing the transgenic plants expressing RNase L with those expressing 2-5Aase. The double transgenic plants showed complete resistance against cucumber mosaic virus (CMV), infection with necrotic spots only forming on the virus-inoculated leaf. On the other hand, although plants inoculated with potato virus Y (PVY) formed necrotic spots on the inoculated leaf and virus amplification could not be detected, all plants died within 20 days of inoculation. The transgenic tobacco plants expressing either 2-5Aase or RNase L activity showed typical disease symptoms with CMV- or PVY-inoculation. These results suggest that the introduced 2-5A system is activated in tobacco cells by dsRNA, the replicating intermediates of RNA viruses, leading to death of the host cells, which has not been observed in mammalian cells.
负责哺乳动物干扰素诱导的抗病毒反应的2-5A系统的主要成分是2',5'-寡腺苷酸合成酶（2-5Aase）和2',5'-寡腺苷酸（2-5A）依赖性核糖核酸酶（RNase L）。通过将表达RNase L的转基因植物与表达2-5Aase的转基因植物杂交，培育出了具有这两种酶活性的转基因烟草植株。双转基因植株对黄瓜花叶病毒（CMV）表现出完全抗性，仅在接种病毒的叶片上形成坏死斑。另一方面，尽管接种马铃薯Y病毒（PVY）的植株在接种叶片上形成了坏死斑且未检测到病毒扩增，但所有植株在接种后20天内死亡。表达2-5Aase或RNase L活性的转基因烟草植株在接种CMV或PVY时表现出典型的病害症状。这些结果表明，引入的2-5A系统在烟草细胞中被RNA病毒的复制中间体dsRNA激活，导致宿主细胞死亡，这在哺乳动物细胞中尚未观察到。
