A dual-signal amplification method for the DNA detection based on exonuclease III
A dual-signal amplification method for the DNA detection based on exonuclease III
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DOI：
10.1016/j.bios.2014.05.046
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发表时间：
2014-11-15
影响因子：
12.6
通讯作者：
Chen, Xi
中科院分区：
文献类型：
--
作者：
Cai, Zhimin;Chen, Yiying;Chen, Xi
设计了一种基于两个分子信标的双信号放大方法，用于人类血色病（HFE）基因检测。 P-1和P-2这两种探针由于3'末端突出，可以抵抗核酸外切酶III（Exo III）的消化，并且可以与Exo III稳定共存。在 HFE 靶标存在的情况下，P-1 与 HFE 靶标杂交，形成具有凹进 3'-羟基末端的双链 DNA，然后被 Exo III 部分消化，释放 HFE 靶标和残留序列 (X)。该X序列可以触发6-羧基荧光素和黑洞猝灭剂对P-2探针的消化，从而导致荧光强度增加。 X序列比HFE靶标更稳定，即使HFE靶标被Exo III消化，也可以长时间循环触发P-2消化。该方法提高了灵敏度，检出限提高了4个数量级，并且表现出优异的选择性，能够很好地区分单碱基错配靶标。 (C) 2014 Elsevier B.V. 保留所有权利。
A dual-signal amplification method based on two molecular beacons was designed for human hemochromatosis (HFE) gene detection. The two probes, P-1 and P-2, could resist the exonuclease III (Exo III) digestion due to the 3 '-termini protrusion, and could coexist stably with Exo III. In the presence of HFE targets, P-1 hybridized with a HFE target to form a duplex DNA with a recessed 3 '-hydroxyl termini and then partially digested by Exo III, releasing the HFE target and a residual sequence (X). This X sequence could trigger the digestion of P-2 probes with 6-carboxy-fluoresceins and Black Hole Quenchers and then result in the increase of fluorescence intensity. The X sequences were more stable than HFE targets and could cyclically trigger the P-2 digestion for a long time even though the HFE targets were digested by Exo III. This method improved the sensitivity and reached 4 orders of magnitude in detection limit, and showed excellent selectivity to discriminate single base mismatched targets well. (C) 2014 Elsevier B.V. All rights reserved.