Frischmuth T, Stanley J
Department of Virus Research, John Innes Institute, John Innes Centre for Plant Science Research, Norwich, United Kingdom.
Virology. 1991 Aug;183(2):539-44. doi: 10.1016/0042-6822(91)90982-h.
Natural infections of the geminivirus African cassava mosaic virus (ACMV) are known to be associated with low levels of defective interfering (DI) DNAs. Recently it has been demonstrated that extrachromosomal copies of the DI DNA, mobilized and amplified from an integrated DI DNA dimer, can ameliorate ACMV symptoms in transformed Nicotiana benthamiana, providing a possible means for the control of cassava mosaic disease. To further understand the molecular basis of the interference phenomenon, we have compared the ability of ACMV and tomato golden mosaic virus (TGMV) genomic components to replicate in leaf discs derived from DI DNA-transformed and control plants. Results indicate that the ACMV DI DNA interferes with the replication of both genomic components of ACMV to a similar extent. TGMV DNA A replicates to normal levels in transformed leaf discs and plants because it is unable to mobilize and amplify ACMV DI DNA. Differences in the relative levels of ACMV genomic components in transformed leaf discs and plants are discussed in terms of DNA replication and the availability of the genomic components for spread throughout the plant.
已知双生病毒非洲木薯花叶病毒（ACMV）的自然感染与低水平的缺陷干扰（DI）DNA有关。最近有研究表明，从整合的DI DNA二聚体中动员并扩增的DI DNA的染色体外拷贝，可以改善转化的本氏烟草中ACMV的症状，为控制木薯花叶病提供了一种可能的方法。为了进一步了解干扰现象的分子基础，我们比较了ACMV和番茄金色花叶病毒（TGMV）基因组成分在源自DI DNA转化植物和对照植物的叶盘中复制的能力。结果表明，ACMV DI DNA对ACMV两个基因组成分的复制干扰程度相似。TGMV DNA A在转化的叶盘和植物中复制到正常水平，因为它无法动员和扩增ACMV DI DNA。本文从DNA复制以及基因组成分在整株植物中传播的可用性方面，讨论了转化叶盘和植物中ACMV基因组成分相对水平的差异。
