Wilson T M
Bioessays. 1989 Jun;10(6):179-86. doi: 10.1002/bies.950100602.
Traditionally, plant viruses are viewed as harmful, undesirable pathogens. However, their genomes can provide several useful 'designer functions' or 'sequence modules' with which to tailor future gene vectors for plant or general biotechnology. The majority (77%) of known plant viruses have single-stranded RNA of the messenger (protein coding) sense as their genetic material. Over the past 4 years, improved in vitro transcription systems and the construction of partial or full-length DNA copies of several plant RNA viruses have enhanced our ability to manipulate and study their genomes, particularly in the context of their pathogenic interactions with host plants. Recently, two forms of genetically engineered protection against plant virus infections have been reported. In both, a virus-related 'interfering' molecule was stably introduced into plants via the DNA-transfer mechanism of Agrobacterium tumefaciens. To date, the choice of 'interfering' molecule has been guided by empirical field-observations and each is effective against only a narrow range of closely-related viruses. As yet, we do not fully understand the molecular mechanism(s) responsible for the observed protection. The ability to manipulate the plant-pathogen relationship is a powerful tool to increase our knowledge and improve future strategies for unconventional cropprotection by genetic engineering techniques.
传统上，植物病毒被视为有害的、不良的病原体。然而，它们的基因组可以提供几种有用的“设计功能”或“序列模块”，用于定制未来用于植物或一般生物技术的基因载体。已知的大多数（77%）植物病毒以信使（蛋白质编码）链的单链RNA作为遗传物质。在过去4年中，改进的体外转录系统以及几种植物RNA病毒部分或全长DNA拷贝的构建，增强了我们操纵和研究其基因组的能力，特别是在它们与宿主植物的致病相互作用方面。最近，已经报道了两种针对植物病毒感染的基因工程保护形式。在这两种形式中，一种与病毒相关的“干扰”分子通过根癌农杆菌的DNA转移机制稳定地导入植物中。迄今为止，“干扰”分子的选择一直基于经验性的田间观察，而且每种分子仅对一小范围的密切相关病毒有效。到目前为止，我们还没有完全了解导致观察到的保护作用的分子机制。操纵植物与病原体关系的能力是一种强大的工具，可增加我们的知识，并通过基因工程技术改进未来非传统作物保护的策略。
