Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University; Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, PR China; Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, PR China; College of Life Sciences, Linyi University, Linyi 276005, PR China.
Department of Microbiology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, PR China.
Virology. 2019 Jan 15;527:38-46. doi: 10.1016/j.virol.2018.11.001. Epub 2018 Nov 16.
To investigate the role of Tobacco vein banding mosaic virus (TVBMV) 3'-UTR in virus systemic infection, three types of deletions were introduced into TVBMV infectious clone pCaTVBMV-GFP. Mutants with deletions at the nucleotide position 8-42, 43-141, or 163-174 in the 3'-UTR failed to cause systemic infection in N. benthamiana plants. Other deletion mutants caused delayed systemic infection and milder vein clearing and mosaic symptoms. Most progeny mutant virus had acquired nucleotides, similar to or different from the deleted nucleotide sequences, after a single passage in the host plant. Nucleotides at the position 8-42 near the 5'-terminus of TVBMV 3'-UTR could form a stem-loop (SL) like structure which was crucial for TVBMV systemic movement in tobacco. We proposed that this SL like structure, and thus 3'-UTR, has an essential role in TVBMV systemic infection.
为了研究烟草镶嵌病毒（TMV）3'-UTR 在病毒系统感染中的作用，我们在 TMV 感染性克隆 pCaTMV-GFP 中引入了三种类型的缺失。在 3'-UTR 核苷酸位置 8-42、43-141 或 163-174 处缺失的突变体不能引起本氏烟植株的系统感染。其他缺失突变体导致系统感染延迟，并出现较轻的叶脉白化和镶嵌症状。在宿主植物中单一传代后，大多数子代突变病毒获得了与缺失核苷酸序列相似或不同的核苷酸。位于 TMV 3'-UTR 5'-末端附近的核苷酸 8-42 能够形成茎环（SL）样结构，该结构对 TMV 在烟草中的系统运动至关重要。我们提出，这种 SL 样结构，以及 3'-UTR，在 TMV 系统感染中具有重要作用。
