Qureshi Muhammad Amir, Butt Muhammad Hassan, Lal Aamir, Vo Thuy T B, Bupi Nattanong, Tabassum Marjia, Im Hyojin, Lee Ahlim, Shamim Amen, Lee Sukchan
Department of Integrative Biotechnology, Sungkyunkwan University, Suwon, South Korea.
Changzhou Maternal and Child Health Care Hospital, Changzhou Medical Center, Nanjing Medical University, Changzhou, Jiangsu, China.
Microbiol Spectr. 2025 Jul;13(7):e0094125. doi: 10.1128/spectrum.00941-25. Epub 2025 May 27.
Multipartite viruses package their genomic segments independently and primarily target plant hosts. A limited number of viruses are identified as targeting animals. The is a family of multipartite single-stranded DNA (ssDNA) plant viruses that encapsidate approximately 1 kb ssDNA segments individually and transmit them via aphids in a circulative, non-propagative manner. Nanoviruses cause significant diseases in host plants, particularly in leguminous crops. Each segment of a nanovirus encodes an open reading frame that functions independently in the infection process. Additionally, each segment contains conserved inverted repeat sequences that create a stem-loop structure, along with a conserved nonanucleotide sequence known as "TAGTATTAC" located within the common region. This research analyzed the variations in the length of the stem-loop neck region of DNA-R segments of Faba bean necrotic yellows virus (FBNYV) and their implications using molecular dynamics (MD) simulations and experimental techniques. Although force field approximations and simulation time scales limit the quality of MD simulations, explicit solvent MD simulations successfully examined key characteristics of the stem-loop structure. The current study focused on the design of mutants based on variations in the neck region length of the stem-loop, construction of mutant infectious clones, and inoculation into the host plant, followed by expression patterns analysis of mutant stem-loop structures. The mutated stem-loop structures showed greater conformational stability compared to the wild type, and these variations in stability correspond to differences in FBNYV expression in the host plant. This finding establishes a framework for further structural and functional analyses of stem-loop structures of nanovirus.IMPORTANCEOur stem-loop modification experiments in Faba bean necrotic yellows virus (FBNYV) highlight its critical role in viral replication and genome stability. Structural changes affected segment maintenance, emphasizing the need for precise stem-loop architecture for efficient replication. The findings provide novel insights into how FBNYV regulates genome integrity and segment functionality.
多分体病毒独立包装其基因组片段，主要侵染植物宿主。仅有少数病毒被确定为侵染动物。[病毒名称]是一类多分体单链DNA（ssDNA）植物病毒，它们分别包裹约1 kb的ssDNA片段，并通过蚜虫以循环、非增殖的方式传播。纳米病毒会在宿主植物中引发严重病害，尤其是在豆科作物中。纳米病毒的每个片段都编码一个开放阅读框，该阅读框在感染过程中独立发挥作用。此外，每个片段都包含保守的反向重复序列，这些序列形成一个茎环结构，以及位于共同区域内的一个名为“TAGTATTAC”的保守九核苷酸序列。本研究使用分子动力学（MD）模拟和实验技术分析了蚕豆坏死黄化病毒（FBNYV）DNA-R片段茎环颈部区域长度的变化及其影响。尽管力场近似和模拟时间尺度限制了MD模拟的质量，但显式溶剂MD模拟成功地研究了茎环结构的关键特征。当前的研究重点是基于茎环颈部区域长度的变化设计突变体、构建突变体感染性克隆并接种到宿主植物中，随后分析突变体茎环结构的表达模式。与野生型相比，突变后的茎环结构表现出更高的构象稳定性，并且这些稳定性的变化与FBNYV在宿主植物中的表达差异相对应。这一发现为进一步对纳米病毒茎环结构进行结构和功能分析建立了一个框架。
重要性
我们对蚕豆坏死黄化病毒（FBNYV）的茎环修饰实验突出了其在病毒复制和基因组稳定性中的关键作用。结构变化影响了片段的维持，强调了精确的茎环结构对于高效复制的必要性。这些发现为FBNYV如何调节基因组完整性和片段功能提供了新的见解。
