核酸是生命体系中最重要的生物大分子之一，随着研究的不断深入，人们认识到其生物功能不仅仅由碱基顺序，一些重要的特殊二级结构同样影响着核酸的功能以及后续的翻译和蛋白质表达的过程。在前期的研究中，针对DNA的各种二级结构研究较为广泛，例如G-四链体、Z-DNA等。相对而言，关于RNA特殊二级结构的功能研究较少，因此这方面的研究仍存在广泛的空间。本项目拟针对一种RNA病毒HCV（丙肝病毒）中的G-四链体，进行结构和功能研究，揭示RNA G-四链体在HCV病毒复制和翻译过程中的调控机制，并将这种特殊二级结构核酸作为抗HCV药物设计的新靶标，设计和筛选不同于以往以酶或蛋白为靶标的抗HCV药物。由于以特殊二级结构核酸为靶标更为直接，且可以避免以酶或蛋白为靶标的药物由于被产生抗性而失效，因此具有更好的应用前景。本项将为RNA G-四链体的功能研究提供新方向，同时也为抗HCV药物设计提供新的策略和理论依据。

Nucleic acids are one of the most important biomacromolecules in living systems. With the deepening of study, some special nucleic acid secondary structures have been recognized to be important in gene expression, such as G-quadruplex, Z-form DNA and so on. In previous study, the study of nucleic acid secondary structure mainly focused on DNA, while not much about RNA. Thus, there's large room in the study of RNA secondary structure. This project would focus on RNA G-quadruplex that formed in a single-stranded positive sense RNA virus HCV, studying the structure and regulatory roles of G-quadruplex in HCV RNA replication and translation. We would try to establish a new target based on G-quadruplex in anti-HCV compound design, other than the traditional common enzyme or protein-targeted drug design, which would be the first example of RNA secondary structure as target for anti-HCV design. This project would provide new insight of G-quadruplex's biological function, and a new strategy of targeting compound design for RNA virus as well.