Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA.
Department of Horticulture, University of Georgia, Athens, GA 30602, USA.
Viruses. 2023 Mar 19;15(3):788. doi: 10.3390/v15030788.
RNA silencing is a crucial mechanism of the antiviral immunity system in plants. Small RNAs guide Argonaut proteins to target viral RNA or DNA, preventing virus accumulation. Small RNA profiles in line PI 420328 with tolerance to cucurbit yellow stunting disorder virus (CYSDV) were compared with those in Gold Star, a susceptible cultivar. The lower CYSDV symptom severity in PI 420328 correlated with lower virus titers and fewer sRNAs derived from CYSDV (vsRNA) compared to Gold Star. Elevated levels of 21- and 22-nucleotide (nt) size class vsRNAs were observed in PI 420328, indicating more robust and efficient RNA silencing in PI 420328. The distribution of vsRNA hotspots along the CYSDV genome was similar in both PI 420328 and Gold Star. However, the 3' UTRs, CPm, and p26 were targeted at a higher frequency in PI 420328.
RNA 沉默是植物抗病毒免疫的关键机制。小 RNA 引导 Argonaut 蛋白靶向病毒 RNA 或 DNA，从而阻止病毒积累。与易感品种 Gold Star 相比，具有耐葫芦科黄矮化病毒（CYSDV）特性的 PI 420328 品系中的小 RNA 图谱进行了比较。PI 420328 中 CYSDV 症状严重程度较低，与 Gold Star 相比，病毒滴度较低，源自 CYSDV 的小 RNA（vsRNA）较少。在 PI 420328 中观察到 21 和 22 核苷酸（nt）大小类别的 vsRNA 水平升高，表明 PI 420328 中 RNA 沉默更强大、更有效。在 PI 420328 和 Gold Star 中，vsRNA 热点沿着 CYSDV 基因组的分布相似。然而，PI 420328 中靶向 3'UTR、CPm 和 p26 的频率更高。
