Colorimetric detection of gene transcript by target-induced three-way junction formation

• Published in: Talanta (Oxford) Vol. 158; pp. 1 - 5
• Main Authors: Wang, Xuchu, Liu, Weiwei, Yin, Binbin, Yu, Pan, Duan, Xiuzhi, Liao, Zhaoping, Liu, Chunhua, Sang, Yiwen, Zhang, Gong, Chen, Yuhua, Tao, Zhihua
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2016
• Subjects: Alternative Splicing; Antigens, Neoplasm - genetics; Biological diversity; Colorimetric detection; Colorimetry; Coupling (molecular); Devices; DNA, Complementary; G-Quadruplexes; Gain; Gene expression; Gene transcript; Genes; Humans; Splicing; Three way junction formation; Transcription, Genetic; Gene transcript; Three way junction formation; Colorimetric detection
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2016.05.039

Gene transcript often varies by alternative splicing, which plays different biological role that results in diversity of gene expression. Therefore, a simple and accurate identification of targeted transcript variant is of prime importance to achieve a precise molecular diagnosis. In this work, we presented a three-way junction based system where two split G-quadruplex forming sequences were coupled into two probes. Only upon the introduction of target gene transcript that offering a specific recognizable splicing site did the two probes assembled into three way junction conformation in a devised process, thus providing a functional G-quadruplex conformation that greatly enhanced hemin peroxidation. A notable resolution for gene splicing site detection was achieved. The detection limitation by colorimetric assay was 0.063μM, and this system has been proved to discriminate even in a single base false level around splicing site (about 3 times of single mismatched analyte to gain an equal signal by perfect analyte ). Furthermore, recoveries of 78.1%, 88.1%, 104.6% were obtained with 0.75μM, 0.25μM, 0.083μM of target, respectively, showing a capacity to further exploit a simple equipped device for gene transcript detection. [Display omitted] •A three way junction based colorimetric system for gene transcript detection was proposed.•The system was label free, and was of high selectivity for splicing site recognition.•The unexpected assembly of DNAzyme was inhibited by the introduction of inhibitory strand in the absence of target.