核酸适配体筛选中单链DNA制备方法的研究进展

Advances of single-stranded DNA generation methods in aptamer screening

中文关键词:  核酸适配体  单链DNA制备  热变性法  生物素-链霉亲和素亲和分离法  变性胶电泳分离法  核酸外切酶消化法  不对称聚合酶链式反应

英文关键词:aptamer  single-stranded DNA generation  heat denaturation method  biotin-streptavidin affinity separation method  denatured gel electrophoresis separation method  exonuclease digestion method  Asymmetric Polymerase Chain Reaction

中文摘要:

      核酸适配体是人工合成的短链核酸，作为分子识别元件，能够与各类靶标物质高特异性、高亲和力的结合，分为单链DNA和RNA两种类型。其中单链DNA适配体由于其稳定性比RNA适配体更好而更受欢迎，因此得到广泛应用。适配体筛选通常是通过配体指数富集系统进化技术 (systematic evolution of ligands by exponential enrichment, SELEX)实现的，筛选能否成功在很大程度上取决于其最关键的单链制备步骤，即将双链DNA转化为相应的单链DNA。目前，存在许多方法可以制备单链DNA，包括热变性法、生物素-链霉亲和素亲和亲和分离法、变性胶电泳分离法、核酸外切酶消化法、不对称聚合酶链式反应 (Polymerase Chain Reaction, PCR)法等。本文在总结文献报道的基础上，具体阐述了各种单链DNA制备方法的原理、优缺点及近5年的应用情况，并对这些单链DNA制备方法进行了比较和展望，以期能为成功筛选各类靶标的适配体提供参考。

英文摘要:

      Aptamers are artificially synthesized short-chain nucleic acids. As molecular recognition elements, they can bind to various types of targets with high specificity and affinity. There are two types of nucleic acid aptamers: single-stranded DNA and RNA. Single-stranded DNA aptamers are more popular than RNA aptamers due to their better stability, so they have been widely used. Aptamers are usually screened through systematic evolution of ligands by exponential enrichment (SELEX). The success of the aptamer selection process depends largely on the most critical step of single-strand generation, which convert double-stranded DNA into the corresponding single-stranded DNA. Up to now, there are many ways to prepare single-stranded DNA, including heat denaturation method, biotin-streptavidin affinity separation method, denatured gel electrophoresis separation method, exonuclease digestion method, asymmetric polymerase chain reaction (PCR) and so on. Based on summarizing the reported literatures, this paper described the principles, advantages and disadvantages of these methods and their applications in recent 5 years in detail. And these single-stranded DNA preparation methods were compared and prospected. It is hoped to provide a reference for the successful screening of aptamers towards various targets.