Balke Ina, Resevica Gunta, Zeltins Andris
Protein Engineering, Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga 1067, Latvia.
Virus Genes. 2007 Oct;35(2):395-8. doi: 10.1007/s11262-007-0087-y. Epub 2007 Mar 14.
In the course of sobemovirus gene cloning the complete genome of Ryegrass mottle virus (RGMoV) was sequenced. Sequence analysis revealed differences including missing and extraneous nucleotides in comparison to the previously published sequence (Zhang, Toriyama, Takanashi, J. Gen. Plant Pathol. 67, 63 (2001)). A gene coding for a typical sobemovirus 3C-like serine protease was identified in ORF2a after multiple sequence alignment analysis. The newly identified 57-amino-acid stretch in ORF2a showed similarities ranging from 38.5 to 50.9% among sequenced genes of sobemovirus proteases. ORF analysis of the RGMoV polyprotein coding sequence demonstrated the arrangement of ORF2b coding for RNA-dependent RNA polymerase (RdRP) in the -1 frame in regard to ORF2a. The localization of conserved among sobemoviruses slippery sequence (UUUAAAC) at the 3'-end of ORF2a suggests the translation of RdRP via a -1 ribosomal frameshifting mechanism, allowing to include the RGMoV in the sobemovirus group with a Cocksfoot mottle virus-like (CfMV-like) genome organization.
在雀麦花叶病毒基因克隆过程中，对黑麦草斑驳病毒（RGMoV）的全基因组进行了测序。序列分析显示，与之前发表的序列（Zhang, Toriyama, Takanashi, J. Gen. Plant Pathol. 67, 63 (2001)）相比，存在差异，包括缺失和多余的核苷酸。经过多序列比对分析，在开放阅读框2a（ORF2a）中鉴定出一个编码典型雀麦花叶病毒3C样丝氨酸蛋白酶的基因。新鉴定出的ORF2a中57个氨基酸的片段在雀麦花叶病毒蛋白酶的已测序基因中显示出38.5%至50.9%的相似性。对RGMoV多聚蛋白编码序列的开放阅读框分析表明，就ORF2a而言，编码RNA依赖的RNA聚合酶（RdRP）的ORF2b在 -1 阅读框中排列。在ORF2a的3'端存在雀麦花叶病毒保守的滑序列（UUUAAAC），这表明RdRP是通过 -1 核糖体移码机制进行翻译的，从而使RGMoV能够归入具有鸭茅斑驳病毒样（CfMV样）基因组结构的雀麦花叶病毒组。
