Hagiwara Yasuhisa, Hasegawa Tomoya, Shoji Atushi, Kuwahara Masayasu, Ozaki Hiroaki, Sawai Hiroaki
Department of Applied Chemistry and Chemical Biology, Gunma University, Kiryu, Gunma 376-8515, Japan.
Bioorg Med Chem. 2008 Jul 15;16(14):7013-20. doi: 10.1016/j.bmc.2008.05.050. Epub 2008 May 29.
Acridone is highly fluorescent and stable against photodegradation, oxidation, and heat. It is also a small molecule with no charge, making it a promising fluorescent agent for use in a DNA probe. Thus, we have prepared 5'-terminal acridone-labeled DNAs by post-modification, and have examined their photophysical properties and their use as donors for a fluorescence resonance energy transfer (FRET) system in combination with a 3'-terminal dabcyl-tagged DNA as an acceptor, which can detect the target DNA by emission-quenching caused by FRET. The FRET with an acridone and dabcyl pair has been found to complement that with fluorescence and dabcyl and other fluorescence-quencher pairs. Significant amounts of quenching of the acridone emissions by guanine in the DNA were observed when guanine was close to acridone, which can be applied as a quencher-free probe for the detection of special sequence of DNA. The DNA bearing acridone at the C5 position of inner thymidine could discriminate the opposite T-T base mismatch, although enhancement of discrimination ability is needed for the practical use of SNP typing.
吖啶酮具有高荧光性，且对光降解、氧化和热稳定。它还是一种不带电荷的小分子，这使其成为用于DNA探针的有前景的荧光剂。因此，我们通过后修饰制备了5'-末端吖啶酮标记的DNA，并研究了它们的光物理性质以及作为荧光共振能量转移（FRET）系统供体的用途，该系统与作为受体的3'-末端二甲基氨基偶氮苯（dabcyl）标记的DNA结合，可通过FRET引起的发射猝灭来检测靶DNA。已发现吖啶酮与二甲基氨基偶氮苯对的FRET补充了荧光与二甲基氨基偶氮苯及其他荧光猝灭剂对的FRET。当鸟嘌呤靠近吖啶酮时，观察到DNA中的鸟嘌呤对吖啶酮发射有大量猝灭，这可作为一种无猝灭剂的探针用于检测特殊的DNA序列。在内侧胸腺嘧啶的C5位置带有吖啶酮的DNA能够区分相反的T-T碱基错配，不过对于单核苷酸多态性（SNP）分型的实际应用而言，还需要提高区分能力。
