Yamana Kazushige, Ohshita Yoshikazu, Fukunaga Yudai, Nakamura Mitsunobu, Maruyama Atsushi
Department of Materials Science and Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2201, Japan.
Bioorg Med Chem. 2008 Jan 1;16(1):78-83. doi: 10.1016/j.bmc.2007.04.053. Epub 2007 May 3.
A new bis-pyrene-labeled oligonucleotide probe (BP-probe) has been designed for the detection of a single base mismatch in single strand (ss) DNA as a target. The sequence of BP-probe was chosen to form stem-loop structure similar to a molecular beacon (MB-probe), yielding bis-pyrene-labeled molecular beacon (BP-MB-probe). Partially double stranded (ds) BP-MB-probes were prepared by complexation with oligonucleotides whose sequences are complementary to the loop segment but not to the stem and exchangeable with the target DNA. The partially ds BP-MB-probes were shown to exhibit monomer fluorescence as major fluorescence, while the ss BP-MB-probe in the stem-loop form displays strong excimer fluorescence. The strand exchange reactions between partially ds BP-MB-probe and target ss DNA in the presence of cationic comb-type copolymer as a catalyst were monitored by the excimer fluorescence changes. The existence of a mismatched base can be determined by the slower PASE rates compared with fully matched DNA.
一种新的双芘标记寡核苷酸探针（BP探针）已被设计用于检测作为靶标的单链（ss）DNA中的单个碱基错配。BP探针的序列被选择为形成类似于分子信标（MB探针）的茎环结构，产生双芘标记分子信标（BP-MB探针）。通过与序列与环段互补但与茎不互补且可与靶DNA交换的寡核苷酸络合来制备部分双链（ds）BP-MB探针。部分ds BP-MB探针显示以单体荧光作为主要荧光，而茎环形式的ss BP-MB探针显示出强的准分子荧光。在阳离子梳型共聚物作为催化剂存在下，通过准分子荧光变化监测部分ds BP-MB探针与靶标ss DNA之间的链交换反应。与完全匹配的DNA相比，碱基错配的存在可以通过较慢的PASE速率来确定。
