Plant viral infections lead to accumulation of virus-derived small interfering RNAs (vsiRNAs) as a result of host defense mechanisms. High-throughput sequencing technology enables vsiRNA profiling analyses from virus infected plants, which provide important insights into virus-host interactions. Potato virus Y (PVY) is a detrimental plant pathogen that can infect a variety of solanaceous crops, e.g., potato, tobacco, tomato, and pepper. We analyzed and characterized vsiRNAs derived from Nicotiana tabacum cv. Samsun infected with two recombinant PVY strains, N-Wi and NTN. We observed that the average percentage of vsiRNAs derived from plants infected with N-Wi was higher than from plants infected with NTN, indicating that N-Wi invokes a stronger host response than NTN in tobacco. The size distribution pattern and polarity of vsiRNAs were similar between both virus strains with the 21 and 22 nucleotide (nt) vsiRNA classes as most predominant and the sense/antisense vsiRNAs ratio nearly equal in the 20−24 nt class. However, the percentage of sense vsiRNAs was significantly higher in the 25−26 nt long vsiRNAs. Distinct vsiRNA hotspots, identifying highly abundant reads of different unique vsiRNA sequences, were observed in both viral genomes. Previous studies found an A or U bias at the 5′ terminal nucleotide position of 21 nt vsiRNAs; in contrast, our analysis revealed a C and U nucleotide bias. This study provides insights that will help further elucidate differential processing of vsiRNAs in plant antiviral defense.

作为宿主防御机制的结果，植物病毒感染导致病毒衍生的小干扰 RNA (vsiRNAs) 的积累。高通量测序技术可以对受病毒感染的植物进行 vsiRNA 谱分析，这为病毒-宿主相互作用提供了重要的见解。马铃薯病毒 Y (PVY) 是一种有害的植物病原体，可感染多种茄科作物，例如马铃薯、烟草、番茄和辣椒。我们分析并表征了来自烟草的vsiRNA简历。Samsun 感染了两种重组 PVY 菌株 N-Wi 和 NTN。我们观察到来自感染 N-Wi 的植物的 vsiRNA 的平均百分比高于感染 NTN 的植物，这表明 N-Wi 比烟草中的 NTN 引起更强的宿主反应。vsiRNAs 的大小分布模式和极性在两种病毒株之间相似，其中 21 和 22 核苷酸 (nt) vsiRNA 类是最主要的，并且有义/反义 vsiRNAs 比率在 20-24 nt 类中几乎相等。然而，在 25-26 nt 长的 vsiRNA 中，有义 vsiRNA 的百分比显着更高。在两个病毒基因组中都观察到了不同的 vsiRNA 热点，可识别不同独特 vsiRNA 序列的高度丰富的读数。之前的研究发现 21 nt vsiRNAs 的 5' 末端核苷酸位置存在 A 或 U 偏差；相比之下，我们的分析揭示了 C 和 U 核苷酸偏差。这项研究提供的见解将有助于进一步阐明 vsiRNA 在植物抗病毒防御中的差异处理。