摘要
目的研究血根碱与c-myc G4-DNA的相互作用。方法采用紫外可见吸收光谱、圆二色谱、变温试验等方法,对血根碱与c-myc G4-DNA的结合常数、结合比例、结合模式及稳定性进行研究。结果在紫外可见吸收光谱中,血根碱在300-350 nm之间的特征吸收峰随c-myc G4-DNA浓度的增加出现明显的减色效应和红移,减色率ΔH=35.4%（Δλ=7 nm）,与c-myc G4-DNA结合常数为3.1×10^4mol/L;G-四链体/血红素过氧化物酶竞争试验中,血根碱竞争血红素引起吸光度下降;变温试验中c-myc G4-DNA的熔点在血根碱作用下升高4.7℃。结论血根碱以结合比例为1∶1外部堆积于c-myc G4-DNA,并促使其结构稳定,这可能是血根碱抗肿瘤的分子机制之一。
Objective To study the interaction between sanguinarine and c-myc G4-DNA.Methods The binding constants,binding modes,binding ratio and stabilization of sanguinarine with c-myc G4-DNA were studied by UV-Vis spectroscopy,circular dichroism,and melting temperature experiment method.Results In UV-Vis spectroscopy, it was found that there was a hypochromise of 35.4%（ Δλ = 7 nm） at the characterized absorption of sanguinarine in the presence of c-myc G4-DNA,and the binding constants value was 3.1 × 10^4 mol/L.In G-quadruplex/hemin peroxidase competition experiment, sanguinarine competed with the hemin to bind with G-quadruplex,which led to a decrease of absorbance.The melting point of cmyc G4 DNA was increased about ΔTm= 4.7 ℃ in melting temperature experiment.Conclusion sanguinarine can increase the stability of c-myc G4-DNA,and bind with c-myc G4-DNA at a ratio of 1： 1 by external stacking,which may be one of the antitumor mechanisms of sanguinarine.
出处
《广东药学院学报》
CAS
2016年第4期431-435,共5页
Academic Journal of Guangdong College of Pharmacy
基金
国家自然科学基金(81001600)
浙江省自然科学基金(LY16B050004)
