基因组包装是含有RNA基因组的植物病毒成熟的关键步骤。病毒表现出显著的包装特异性,尽管共包装细胞RNA的可能性。迄今为止报道了三种不同类型的病毒基因组包装系统。最近升级的I型基因组包装系统涉及以能量依赖的方式对RNA基因组进行成核和衣壳化,在大多数具有较小基因组大小的植物RNA病毒中观察到,而II型和III型包装系统,主要在噬菌体和大型真核DNA病毒中发现,以能量依赖的方式涉及基因组易位和包装在前端内部,即,利用ATP。尽管ATP对于所有三个包装系统都是必不可少的,每个机械系统都采用独特的ATP水解模式和基因组包装机制。植物RNA病毒是农业和园艺作物的严重威胁,并造成巨大的经济损失。开发针对植物RNA病毒的控制策略需要深入了解其基因组组装和包装机制。在我们之前的研究和精心策划的实验的基础上,我们已经揭示了它们的分子机制,并为I型包装系统提出了一个假设模型,重点是较小的植物RNA病毒。这里,在这次审查中,我们向研究人员通报了促进植物RNA病毒基因组包装和病毒体组装过程解剖的技术突破。
Genome packaging is the crucial step for maturation of plant viruses containing an RNA genome. Viruses exhibit a remarkable degree of packaging specificity, despite the probability of co-packaging cellular RNAs. Three different types of viral genome packaging systems are reported so far. The recently upgraded type I genome packaging system involves nucleation and encapsidation of RNA genomes in an energy-dependent manner, which have been observed in most of the plant RNA viruses with a smaller genome size, while type II and III packaging systems, majorly discovered in bacteriophages and large eukaryotic DNA viruses, involve genome translocation and packaging inside the prohead in an energy-dependent manner, i.e., utilizing ATP. Although ATP is essential for all three packaging systems, each machinery system employs a unique mode of ATP hydrolysis and genome packaging mechanism. Plant RNA viruses are serious threats to agricultural and horticultural crops and account for huge economic losses. Developing control strategies against plant RNA viruses requires a deep understanding of their genome assembly and packaging mechanism. On the basis of our previous studies and meticulously planned experiments, we have revealed their molecular mechanisms and proposed a hypothetical model for the type I packaging system with an emphasis on smaller plant RNA viruses. Here, in this review, we apprise researchers the technical breakthroughs that have facilitated the dissection of genome packaging and virion assembly processes in plant RNA viruses.