Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
Biomolecules. 2020 Mar 21;10(3):480. doi: 10.3390/biom10030480.
A bromoaryltetrazole-modified uridine was synthesized as a new RNA building block for bioorthogonal, light-activated and postsynthetic modification with commercially available fluorescent dyes. It allows "photoclick"-type modifications by irradiation with light (300 nm LED) at internal and terminal positions of presynthesized RNA with maleimide-conjugated fluorophores in good yields. The reaction was evidenced for three different dyes. During irradiation, the emission increases due to the formation of an intrinsically fluorescent pyrazoline moiety as photoclick product. The fluorogenecity of the photoclick reaction was significantly enhanced by energy transfer between the pyrazoline as the reaction product (poor emitter) and the photoclicked dye as the strong emitter. The RNA-dye conjugates show remarkable fluorescent properties, in particular an up to 9.4 fold increase of fluorescence, which are important for chemical biology and fluorescent imaging of RNA in cells.
一种溴代芳基四唑修饰的尿苷被合成作为一种新的 RNA 构建模块，用于生物正交、光激活和后合成修饰，可与市售的荧光染料反应。它允许通过在内部和末端位置用商业可得的马来酰亚胺缀合荧光染料对预合成的 RNA 进行“光点击”型修饰，产率良好。该反应适用于三种不同的染料。在照射过程中，由于形成了作为光点击产物的本征荧光吡唑啉部分，发射强度增加。通过作为反应产物（弱发射器）的吡唑啉和作为强发射器的光点击染料之间的能量转移，显著增强了光点击反应的荧光生成能力。RNA-染料缀合物显示出显著的荧光性质，特别是荧光强度增加了高达 9.4 倍，这对于化学生物学和细胞中 RNA 的荧光成像非常重要。
