Development of the virus vaccine by the elucidation of the virulence of a plant virus

为了阐明RNA去纯化的机制，了解PAP如何识别和靶向各种RNA，研究了PAP与芜菁花叶病毒基因组连接蛋白（VPg）的相互作用。VPg可以在不依赖于cap的翻译中作为cap类似物发挥作用，并潜在地将PAP靶向到含ires的无帽RNA上。在这项工作中，荧光光谱和高效液相色谱技术用于定量描述PAP去嘌呤活性和PAP- vpg相互作用。PAP与VPg高亲和力结合（29.5 nM）；这个反应是焓驱动的，熵有利的。此外，VPg是小麦胚裂解液中PAP去纯化RNA的有效抑制剂，并与烟草蚀刻病毒（TEV）衍生的结构化RNA竞争PAP结合。VPg可能通过抑制植物的一种防御机制而具有进化优势，并且还表明该蛋白可能用于对抗rip的细胞毒性活性。

To elucidate the mechanism of RNA depurination, and to understand how PAP recognizes and targets various RNAs, the interactions between PAP and Turnip mosaic virus genome linked protein (VPg) were investigated. VPg can function as a cap analog in cap-independent translation, and potentially target PAP to uncapped IRES-containing RNA. In this work, fluorescence spectroscopy and HPLC techniques were used to quantitatively describe PAP depurination activity and PAP-VPg interactions. PAP binds to VPg with high affinity (29.5 nM); the reaction is enthalpically driven and entropically favored. Further, VPg is a potent inhibitor of PAP depurination of RNA in wheat germ lysate, and competes with structured RNA derived from tobacco etch virus (TEV) for PAP binding. VPg may confer an evolutionary advantage by suppressing one of the plant defense mechanisms, and also suggests the possible use of this protein against the cytotoxic activity of RIPs.