Institute of Integrative Biology, Liverpool University, Liverpool, United Kingdom.
Nucleic Acid Ther. 2013 Feb;23(1):88-92. doi: 10.1089/nat.2012.0386. Epub 2012 Dec 5.
Nearly all aptamers identified so far for any given target molecule have been specific for the same binding site (epitope). The most notable exception to the 1 aptamer per target molecule rule is the pair of DNA aptamers that bind to different epitopes of thrombin. This communication refutes the suggestion that these aptamers exist because different partitioning methods were used when they were selected. The possibility that selection of these aptamers was biased by conflicting secondary structures was also investigated and found not to contribute. The preparation of protein-coated magnetic beads for systematic evolution of ligands by exponential enrichment (SELEX) and the different specificities of the thrombin aptamers for the α and β forms of thrombin are also reported.
迄今为止，针对任何给定靶分子鉴定的几乎所有适体都针对相同的结合位点（表位）具有特异性。针对靶分子的 1 个适体规则的最显著例外是一对与凝血酶不同表位结合的 DNA 适体。本通讯驳斥了这些适体存在的观点，因为在选择它们时使用了不同的分区方法。还研究了选择这些适体是否受到冲突二级结构的影响，但未发现有影响。本文还报告了用于配体指数富集的系统进化（SELEX）的蛋白质包被的磁性珠的制备和凝血酶适体对凝血酶的α和β形式的不同特异性。
