Abstract Leaf curl diseases caused by tomato leaf curl Palampur virus (ToLCPalV) is responsible for considerable yield losses and pathogenicity of virus is attributed to the expression of a viral protein, AV2. The present study was designed to elucidate role of AV2 in virus infection and characterize its interaction with tomato F-box Kelch protein (KFB). The interaction between AV2 and KFB was assayed using several approaches including yeast two hybrid screening (Y2H) and bimolecular fluorescence complementation (BiFC). Interestingly, transient co-expression of AV2 and KFB in Nicotiana benthamiana resulted in destabilization of the KFB protein. This in turn was associated with ~3.4-fold downregulation of KFB transcripts in ToLCPalV infected leaves. The N. benthamiana plants inoculated with wild-type or mutant ToLCPalV strains also showed a significant difference in phenylalanine ammonia-lyase (PAL) activity. These results provide valuable insights into molecular steps underlying virulence of ToLCPalV on tomato plants.

中文翻译：

---

番茄卷叶Palampur病毒AV2蛋白与番茄F-box Kelch蛋白相互作用，增强病毒感染过程中苯丙氨酸解氨酶活性

摘要 由番茄卷叶帕兰普尔病毒 (ToLCPalV) 引起的卷叶病是造成相当大的产量损失的原因，病毒的致病性归因于病毒蛋白 AV2 的表达。本研究旨在阐明 AV2 在病毒感染中的作用，并表征其与番茄 F-box Kelch 蛋白 (KFB) 的相互作用。使用多种方法测定 AV2 和 KFB 之间的相互作用，包括酵母二杂交筛选 (Y2H) 和双分子荧光互补 (BiFC)。有趣的是，AV2 和 KFB 在本氏烟草中的瞬时共表达导致 KFB 蛋白的不稳定。这反过来又与 ToLCPalV 感染的叶子中 KFB 转录本约 3.4 倍的下调有关。然后。用野生型或突变型 ToLCPalV 菌株接种的本塞米亚植物也表现出苯丙氨酸解氨酶 (PAL) 活性的显着差异。这些结果为 ToLCPalV 对番茄植物毒力的潜在分子步骤提供了宝贵的见解。