Study on the effects of Mg2+ on the binding between Bloom syndrome helicase and G4DNA
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摘要: 利用荧光偏振技术检测了Mg2+对G4DNA、BLM-G4DNA复合物和BLM642-1290解旋酶与G4DNA结合的影响.结果表明,G4DNA荧光偏振值随着Mg2+浓度的增加而增加(〖WTBX〗P〖WTBZ〗0.01);BLM-G4DNA复合物的荧光偏振值随着Mg2+浓度的增加出现下降升高下降的变化趋势(〖WTBX〗P〖WTBZ〗0.01);G4DNA与BLM642-1290解旋酶结合的荧光偏振值随着Mg2+浓度的增加而逐渐下降(〖WTBX〗P〖WTBZ〗0.01);分析不同Mg2+浓度下两种分子结合的〖WTBX〗Kd〖WTBZ〗值,发现Mg2+浓度为3.0 mmol/L时,BLM642-1290解旋酶与G4DNA最容易结合,表明适量Mg2+浓度会促进BLM642-1290与G4DNA的结合,但会引起两种分子结合的形状、流动性和电荷等性质的改变.这些结果可为进一步研究BLM解旋酶对G4DNA的作用机理提供相关资料.Abstract: This paper studied the effects of Mg2+ on G4DNA, BLM-G4DNA complex, and the binding of BLM642-1290 helicase and G4DNA using fluorescence anisotropy technology.The results indicated that the fluorescence anisotropy of G4DNA increased with Mg2+ concentration (〖WTBX〗P〖WTBZ〗0.01); The anisotropy of BLM-G4DNA complex showed varied tendency of decrease-increase-decrease with Mg2+ concentration (〖WTBX〗P〖WTBZ〗0.01);The anisotropy of the binding between the helicase and G4DNA gradually declined following Mg2+ concentration (〖WTBX〗P〖WTBZ〗0.01); The binding was most likely to occur between the helicase and G4DNA when Mg2+ concentrations was 3.0 mmol/L, which suggested that the suitable amount of Mg2+ could promote the binding of the helicase and G4DNA but that could lead to the change of the binding properties of two molecules including the shape, flow ability, and charge. These results provided useful data for studying the interaction mechanism between BLM helicase and G4DNA.
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Key words:
- BLM helicase /
- G4DNA /
- Mg2+ /
- fluorescence polarization technology
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