Chen Xiaohan, Wang Liang, Roozbahani Golbarg M, Zhang Youwen, Xiang Jialing, Guan Xiyun
Department of Chemistry, Illinois Institute of Technology, Chicago, IL, USA.
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, P. R. China.
Electrophoresis. 2018 Oct;39(19):2410-2416. doi: 10.1002/elps.201800193. Epub 2018 Aug 2.
Baxα, a key tumor suppressor gene, will not be expressed correctly as a result of single nucleotide mutation in its microsatellite region; Instead, BaxΔ2, an isoform of Baxα, is often produced. In addition, lack of the exon 2 due to an alternative splicing, BaxΔ2 has the same sequence as Baxα except single base deletion from eight continuous guanines (G8) to G7. Most of the currently available methods for Bax∆2 detection are inefficient and time-consuming, and/or require the use of labels or dyes. In this work, we reported a label-free nanopore sensing strategy to differentiate between Baxα and BaxΔ2 with a DNA polymer as a molecular probe based on alternative spliced sequences. Two DNA molecules were designed to selectively detect Baxα and BaxΔ2, respectively. The method was rapid, accurate, and highly sensitive: picomolar concentrations of target nucleic acids could be detected in minutes. Our developed simple and fast nanopore-based detection strategy is not only useful for distinguishing between Baxα and Bax∆2, but also provides a useful tool for detection of other single-base mutations in genetic diagnosis.
Baxα是一种关键的肿瘤抑制基因，由于其微卫星区域的单核苷酸突变，它无法正确表达；相反，经常会产生Baxα的一种异构体BaxΔ2。此外，由于选择性剪接导致外显子2缺失，BaxΔ2与Baxα具有相同的序列，只是从八个连续的鸟嘌呤（G8）中缺失了一个碱基变为G7。目前大多数用于检测Bax∆2的方法效率低下且耗时，和/或需要使用标记物或染料。在这项工作中，我们报道了一种无标记的纳米孔传感策略，基于选择性剪接序列，以DNA聚合物作为分子探针来区分Baxα和BaxΔ2。设计了两个DNA分子分别选择性地检测Baxα和BaxΔ2。该方法快速、准确且高度灵敏：几分钟内就能检测到皮摩尔浓度的目标核酸。我们开发的基于纳米孔的简单快速检测策略不仅有助于区分Baxα和Bax∆2，还为基因诊断中其他单碱基突变的检测提供了一种有用的工具。
