Interaction Between G-Quadruplex And Anti-Tumor Small Molecules

Human telomeric DNA consists of the sequence, 5'-TTAGGG-3', which could form G-quadruplex structure by Hoogsteen hydrogen bonds under physiological condition. G-quadruplex plays a very important role in inhibiting the activity of telomerase that has close relation with cellular malignant transformation and maintaining cellular division and proliferation. Therefore, using G-quadruplex as a target to investigate the interaction between quadruplex and small molecules is one of important ways to find anti-tumor drugs.Methylene blue (MB) is a kind of cationic dyes which has found applications in photodynamic therapy; and quercetin is a bioactive plant flavonoid with the anti-cancer, anti-tumor function. In this thesis, the interactions between G-quadruplex and methylene blue, quercetin have been investigated. Several conclusions have been obtained:1. The formation of G-quadruplex is affected by the concentrations of metal cation and DNA, and so on. s6-DNA forms parallel monomeric G-quadruplex under low [K~+] (18 mM), and dimer under high [K~+] (118 mM). Decreasing [DNA], the equilibrium between monomer and dimer is shifted to...