肽核酸与蛋白质互作机理及肽核酸适配体筛选的毛细管电泳方法学研究

核酸适配体从理论上可认为是各种靶标的化学抗体。但实际应用则需对磷酸骨架进行修饰以提高亲和性和稳定性。本项目提出全新的肽核酸适配体"PNAaptamer" 概念，研究肽核酸（将核酸的磷酸骨架和糖环替换为肽，但保留碱基的序列）与蛋白质靶标的相互作用机理。基于毛细管电泳技术，以凝血酶及其适配体为亲和作用模型，研究肽核酸对功能蛋白HSA、IgG、NAaseA的识别及影响其互作的化学因素和生物学因素。建立PNAaptamer的快速筛选方法。通过模拟仿真分子设计和生物信息学方法进行理论计算，实现肽核酸-蛋白质作用的结构预测及"微流体-肽核酸-蛋白质"作用的动态仿真。利用肽核酸对非核酸分子蛋白质的相互作用，从肽骨架和碱基序列双维度调节对蛋白质靶标的识别，对于解决蛋白质靶标的高亲和性、特异性、稳定性和生物活性的分子识别问题具有重要的科学意义和应用价值。所提出的概念及研究思路具有创新性。

Aptamer can be considered theoretically　as chemical antibody for various targets. Its actual application usually requires the modification of the phosphate backbone in order to improve its affinity and stability. In this project, a new concept of "peptide nucleic acid aptamer", named as PNAaptamer is presented. We will study the interaction mechanism of protein target and peptide nucleic acid (PNA) , in which phosphate backbone and sugar ring of DNA or RNA are substituted by peptide backbone but retained their base sequence . Based on capillary electrophoresis, with thrombin and its aptamer interaction as model, the interaction of functional protein HSA, IgG and NAase A with PNA will be studied and the effect of chemical and biological factors to the interaction will be evaluated. The capillary electrophoresis method for PNAaptamer fast selection will be established. Based on theoretical calculation, biological information and simulation of molecular design, the primary dynamic "microfluid- PNA- protein" interaction is expected to show and the prediction of PNA and functional protein interaction is expected to be achieved, which will be helpful for guidance the PNA library design and improve the PNAaptamer selection efficiency. Two-dimension of regulation of PNA interacted with non nucleic acid target protein based on peptide backbone and nucleotide sequence design has scientific significance and potential application for molecular recognition of protein with ligand, which is with high affinity, specificity, stability and biological activity. The concept and idea proposed in this project are innovative.