Prasad Bagineni, Doimo Mara, Andréasson Måns, L'Hôte Valentin, Chorell Erik, Wanrooij Sjoerd
Department of Chemistry, Umeå University 90187 Umeå Sweden
Department of Medical Biochemistry and Biophysics, Umeå University Umeå 90736 Sweden
Chem Sci. 2022 Feb 1;13(8):2347-2354. doi: 10.1039/d1sc05816a. eCollection 2022 Feb 23.
G-quadruplex (G4) DNA structures are implicated in central biological processes and are considered promising therapeutic targets because of their links to human diseases such as cancer. However, functional details of how, when, and why G4 DNA structures form are largely missing leaving a knowledge gap that requires tailored chemical biology studies in relevant live-cell model systems. Towards this end, we developed a synthetic platform to generate complementary chemical probes centered around one of the most effective and selective G4 stabilizing compounds, Phen-DC3. We used a structure-based design and substantial synthetic devlopments to equip Phen-DC3 with an amine in a position that does not interfere with G4 interactions. We next used this reactive handle to conjugate a BODIPY fluorophore to Phen-DC3. This generated a fluorescent derivative with retained G4 selectivity, G4 stabilization, and cellular effect that revealed the localization and function of Phen-DC3 in human cells. To increase cellular uptake, a second chemical probe with a conjugated cell-penetrating peptide was prepared using the same amine-substituted Phen-DC3 derivative. The cell-penetrating peptide conjugation, while retaining G4 selectivity and stabilization, increased nuclear localization and cellular effects, showcasing the potential of this method to modulate and direct cellular uptake as delivery vehicles. The applied approach to generate multiple tailored biochemical tools based on the same core structure can thus be used to advance the studies of G4 biology to uncover molecular details and therapeutic approaches.
G-四链体（G4）DNA结构与核心生物学过程相关，由于其与癌症等人类疾病的联系，被认为是很有前景的治疗靶点。然而，关于G4 DNA结构如何、何时以及为何形成的功能细节大多缺失，留下了一个知识空白，这需要在相关活细胞模型系统中进行有针对性的化学生物学研究。为此，我们开发了一个合成平台，以围绕最有效和选择性最强的G4稳定化合物之一Phen-DC3生成互补化学探针。我们采用基于结构的设计和大量的合成改进，在不干扰G4相互作用的位置为Phen-DC3引入一个胺基。接下来，我们利用这个反应性基团将一个BODIPY荧光团与Phen-DC3偶联。这产生了一种具有保留的G4选择性、G4稳定作用和细胞效应的荧光衍生物，揭示了Phen-DC3在人类细胞中的定位和功能。为了增加细胞摄取，使用相同的胺基取代的Phen-DC3衍生物制备了一种与细胞穿透肽偶联的第二种化学探针。细胞穿透肽偶联在保留G4选择性和稳定作用的同时，增加了核定位和细胞效应，展示了这种方法作为递送载体调节和指导细胞摄取的潜力。因此，基于相同核心结构生成多种定制生化工具的应用方法可用于推进G4生物学研究，以揭示分子细节和治疗方法。
