Nagatoishi Satoru, Nojima Takahiko, Galezowska Elzbieta, Juskowiak Bernard, Takenaka Shigeori
Department of Applied Chemistry, Kyushu University, Motooka, 819-0395, Japan.
Chembiochem. 2006 Nov;7(11):1730-7. doi: 10.1002/cbic.200600179.
The dual-labeled oligonucleotide derivative, FAT-0, carrying 6- carboxyfluorescein (FAM) and 6-carboxytetramethylrhodamine (TAMRA) labels at the 5' and 3' termini of the thrombin-binding aptamer (TBA) sequence 5'-GGT TGG TGT GGT TGG-3', and its derivatives, FAT-n (n=3, 5, and 7) with a spacer at the 5'-end of a TBA sequence of T(m)A (m=2, 4, and 6) have been designed and synthesized. These fluorescent probes were developed for monitoring K(+) concentrations in living organisms. Circular dichroism, UV-visible absorption, and fluorescence studies revealed that all FAT-n probes could form intramolecular tetraplex structures after binding K(+). Fluorescence resonance energy transfer and quenching results are discussed taking into account dye-dye contact interactions. The relationship between the fluorescence behavior of the probes and the spacer length in FAT-n was studied in detail and is discussed.
双标记寡核苷酸衍生物FAT-0，在凝血酶结合适体（TBA）序列5'-GGT TGG TGT GGT TGG-3'的5'和3'末端带有6-羧基荧光素（FAM）和6-羧基四甲基罗丹明（TAMRA）标记，及其衍生物FAT-n（n = 3、5和7），在T(m)A（m = 2、4和6）的TBA序列的5'端带有间隔基，已被设计并合成。这些荧光探针被开发用于监测活生物体中的钾离子浓度。圆二色性、紫外可见吸收和荧光研究表明，所有FAT-n探针在结合钾离子后都能形成分子内四链体结构。考虑到染料-染料接触相互作用，讨论了荧光共振能量转移和猝灭结果。详细研究并讨论了FAT-n中探针的荧光行为与间隔基长度之间的关系。
