Department of Life Science, Faculty of Advanced Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi, Chiba 275-0016, Japan.
Structure and Dynamics of Biomolecular Machines, Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Institut de Biologie Moléculaire et Cellulaire, 15 Rue René Descartes, F-67000 Strasbourg, France.
Biochimie. 2018 Feb;145:91-97. doi: 10.1016/j.biochi.2017.10.010. Epub 2017 Oct 18.
Aptamers are nucleic acids that bind to a target molecule with high affinity and specificity, which are selected from systematic evolution of ligands by exponential enrichment (SELEX). Aptamers feature high affinity and specificity to their target molecule and a large structural diversity; biophysical tools, together with structural studies, are essential to reveal the mechanism of aptamers recognition. Furthermore, understanding the mechanism of action would also contribute to their development for therapeutic applications. Isothermal titration calorimetry (ITC) is a fast and robust method to study the physical basis of molecular interactions. In a single experiment, it provides all thermodynamic parameters of a molecular interaction, including dissociation constant, K; Gibbs free energy change, ΔG; enthalpy change, ΔH; entropy change, ΔS; and stoichiometry, N. The development of modern microcalorimeters significantly contributed to the expansion of the ITC use in biological systems. Therefore, ITC has been applied to the development of small therapeutic agents that bind to target proteins and is increasingly being used to study aptamer-target protein interactions. This review focuses on thermodynamic approaches for understanding the molecular principles of aptamer-target interactions.
适体是通过指数富集配体系统进化（SELEX）从核酸中筛选出的与靶分子具有高亲和力和特异性的核酸。适体对其靶分子具有高亲和力和特异性，并且结构多样性很大；生物物理工具与结构研究对于揭示适体识别的机制至关重要。此外，了解作用机制也将有助于它们开发用于治疗应用。等温滴定量热法（ITC）是研究分子相互作用的物理基础的快速而强大的方法。在单个实验中，它提供了分子相互作用的所有热力学参数，包括解离常数 K、吉布斯自由能变化 ΔG、焓变 ΔH、熵变 ΔS 和计量数 N。现代微量热计的发展极大地促进了 ITC 在生物系统中的应用扩展。因此，ITC 已被应用于与靶蛋白结合的小分子治疗剂的开发，并越来越多地用于研究适体-靶蛋白相互作用。本综述重点介绍了理解适体-靶相互作用的分子原理的热力学方法。
