Plant Pathology Programme, James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK.
Virus Res. 2011 Sep;160(1-2):435-8. doi: 10.1016/j.virusres.2011.07.007. Epub 2011 Jul 21.
Currently, all of the RNA2 molecules described for all of the more than thirty sequenced isolates of the three tobraviruses, Tobacco rattle virus (TRV), Pea early-browning virus (PEBV) and Pepper ringspot virus (PepRSV), have the virus coat protein (CP) gene located in the 5' proximal position. However, sequencing of the RNA2 of the SYM isolate of TRV revealed that this isolate has a unique genome structure in which the virus CP gene is located in the central region of RNA2 downstream of three completely novel open reading frames (ORFN1, ORFN2 and ORFN3). An infectious clone of SYM RNA2 was constructed and mutations were introduced separately into each of the novel genes to interrupt their translation. However, none of the mutations resulted in any noticeable change in the ability of TRV RNA1 or RNA2 to replicate and move systemically in the leaves or roots of infected plants. In addition, individual expression of the novel ORFs either from a Potato virus X (PVX) vector or from a binary plasmid in Agrobacterium tumefaciens did not reveal any potential function.
目前，所有已测序的 30 多种烟草花叶病毒（TRV）、豌豆早褐斑病毒（PEBV）和胡椒环斑病毒（PepRSV）的 3 个分离株的所有 RNA2 分子都具有位于 5'近端位置的病毒外壳蛋白（CP）基因。然而，对 TRV 的 SYM 分离株的 RNA2 进行测序显示，该分离株具有独特的基因组结构，其中病毒 CP 基因位于 RNA2 的中央区域，位于三个完全新颖的开放阅读框（ORFN1、ORFN2 和 ORFN3）的下游。构建了 SYM RNA2 的传染性克隆，并分别在每个新基因中引入突变以中断其翻译。然而，这些突变都没有导致 TRV RNA1 或 RNA2 在感染植物的叶片或根部中复制和系统移动的能力有任何明显的变化。此外，来自马铃薯病毒 X（PVX）载体或农杆菌中的二元质粒的单个表达都没有显示出任何潜在的功能。
