Plant Pathology Department, University of Florida, Gainesville, FL 32611, USA.
Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA.
Viruses. 2021 Oct 22;13(11):2129. doi: 10.3390/v13112129.
(CTV), the largest non-segmented plant RNA virus, has several peculiar features, among which is the production of a 5'-terminal long non-coding RNA (lncRNA) termed low-molecular-weight tristeza 1 (LMT1). In this study, we found that p33, a unique viral protein that performs multiple functions in the virus infection cycle, specifically binds LMT1, both in vivo and in vitro. These results were obtained through the expression of p33 under the context of the wild type virus infection or along with a mutant CTV variant that does not produce LMT1 as well as via ectopic co-expression of p33 with LMT1 in leaves followed by RNA immunoprecipitation and rapid amplification of cDNA ends assays. Further experiments in which a recombinant p33 protein and an in vitro transcribed full-length LMT1 RNA or its truncated fragments were subjected to an electrophoretic mobility shift assay demonstrated that p33 binds to at least two distinct regions within LMT1. To the best of our knowledge, this is the first report of a plant virus protein binding to a lncRNA produced by the same virus. The biological significance of the interaction between these two viral factors is discussed.
(CTV)，最大的非分段植物 RNA 病毒，具有几个特殊的特征，其中包括产生一种 5'-末端长非编码 RNA（lncRNA），称为低分子量褪绿 1（LMT1）。在这项研究中，我们发现 p33，一种在病毒感染周期中具有多种功能的独特病毒蛋白，特异性地结合 LMT1，无论是在体内还是体外。这些结果是通过在野生型病毒感染的情况下表达 p33 或与不产生 LMT1 的突变 CTV 变体一起获得的，以及通过在叶中异位共表达 p33 和 LMT1 然后进行 RNA 免疫沉淀和快速扩增 cDNA 末端分析。进一步的实验中，重组 p33 蛋白和体外转录的全长 LMT1 RNA 或其截断片段进行电泳迁移率变动分析表明，p33 结合到 LMT1 内的至少两个不同区域。据我们所知，这是第一个报道植物病毒蛋白与同一病毒产生的 lncRNA 结合的报告。讨论了这两种病毒因子之间相互作用的生物学意义。
