GENOME ORGANIZATION AND EVOLUTION OF RNA VIRUSES

详细的计算机辅助蛋白质序列比较分析和 正链、负链和双链中的基因排列 进行RNA病毒以预测基因产物的功能， 推导基因组组织原理，并提出进化论 场景。RNA病毒基因组较小，基因组序列完整 这些病毒已知的大多数组的代表是 目前可用于大规模的比较和发展 学习。正链RNA病毒具有有限数量的保守区 主要参与基因组复制和表达的蛋白质。 两种假定的甲基转移酶结构域，其中一种是保守的 在类阿尔法超群病毒中，另一种在黄病毒中， 已经被确认了。戊型肝炎病毒多聚蛋白的结构域组织 进行了详细的研究，结果表明，这种病毒与 风疹病毒和甜菜坏死性黄脉病毒，是一种植物病毒。 这些病毒的进化似乎涉及到几个基因组 重排活动。推测的木瓜蛋白酶样酶结构域是 在每一种病毒的多蛋白中被鉴定。三、分析了 甜菜黄化闭锁病毒基因组揭示了一种独特的基因结构， 具有编码与两种蛋白相关的蛋白的基因 不同的正链RNA病毒组，对细胞热休克 蛋白质。结果表明，该病毒的外壳蛋白基因为 复制的。这是我国首次发现的衣壳蛋白基因复制。 带有细长颗粒的病毒。关于生物进化的一般概念 基于保守性之间相互作用的正链RNA病毒 基因阵列和基因模块改组正在开发中。工作于 关于病毒基因组组织和衍生的信息综述 进化方案的研究正在进行中。序列的比较 由双链RNA编码的蛋白质显示出非常有限的保守性。 在不同基团中唯一保守的序列是 依赖于RNA的RNA聚合酶。这一序列与 正链RNA病毒的聚合酶。系统发育分析 提示双链rna病毒可能不是一个单系。 一群人。不同的双链RNA病毒群可能已经进化 来自不同的正链RNA病毒群。 该项目的意义在于有独特的机会进行比较 组织大量不同种类的完整基因组 相互之间的相似程度，并洞察可能的 生物大类遗传多样性的进化途径 病毒。

Detailed computer-assisted comparative analysis of protein sequences & gene arrangement in positive-strand, negative-strand and double-stranded RNA viruses was performed in order to predict functions of gene products, to deriveprinciples of genome organization, and to propose evolutionary scenarios. RNA viruses have small genomes and complete genome sequences representative of the majority of known groups of these viruses are currently available allowing for large-scale comparative and evolutionary studies. Positive-strand RNA viruses have a limited number of conserved proteins that are mostly involved in genome replication and expression. Two types of putative methyltransferase domains, one of which is conserved in viruses of the alpha-like supergroup, and the other in flaviviruses, have been identified. Domain organization of Hepatitis E virus polyprotein was explored in detail and it was shown that this virus is related to Rubella virus and to Beet necrotic yellow vein virus, a plant furovirus. Evolution of these viruses appeared to involve several genome rearrangement events. Putative papain-like protease domains were identified in the polyproteins of each of these viruses. Analysis of the genome of Beet yellows closterovirus revealed a unique gene organization, with genes coding for proteins related to the respective proteins of two distinct groups of positive-strand RNA viruses, and to cellular heat shock proteins. It was shown that the coat protein gene of this virus is duplicated. This is the first example of coat protein gene duplication in viruses with elongated particles. A general concept of evolution of positive-strand RNA viruses based on the interplay between conservation of gene arrays and gene module shuffling is being developed. Work on summation of the information on virus genome organization and derivation of evolutionary schemes is in progress. Comparison of the sequences of proteins encoded by double-stranded RNA showed very limited conservation. The only sequence conserved among different groups was that of a domain of the RNA-dependent RNA polymerase. This sequence is distantly related to the polymerases of positive-strand RNA viruses. Phylogenetic analysis suggested that double-stranded RNA viruses may not be a monophyletic group. Different groups of double-stranded RNA viruses could have evolved from distinct groups of positive-strand RNA viruses. The significance of the project lies in the unique opportunity to compare the organization of a large number of complete genomes with varying degree of similarity to each other and to gain insight into the possible pathways of evolution of the genetic diversity of vast classes of viruses.