Delcros J G, Sturkenboom M C, Basu H S, Shafer R H, Szöllösi J, Feuerstein B G, Marton L J
Department of Neurological Surgery, School of Medicine, University of California, San Francisco 94143.
Biochem J. 1993 Apr 1;291 ( Pt 1)(Pt 1):269-74. doi: 10.1042/bj2910269.
The interactions of spermine and polyamine analogues with synthetic polynucleotides of various base sequences complexed with ethidium bromide (EB) were investigated using measurements of fluorescence intensity and steady-state fluorescence polarization. Spermine and polyamine analogues displaced some but not all of the EB bound to poly(dA-dT).poly(dA-dT) or poly(dG-dC).poly(dG-dC), suggesting that polyamines may stabilize these polynucleotides in a conformation with reduced affinity for EB. Modifications of the aliphatic backbone of spermine have pronounced effects on its ability to displace EB from poly(dA-dT).poly(dA-dT) but not from poly-(dG-dC).poly(dG-dC). Spermine and some but not all of the polyamine analogues caused fluorescence depolarization when they interacted with the complex of EB and poly(dA-dT).poly-(dA-dT). Neither spermine nor any of the analogues, however, induced fluorescence depolarization in the complex of EB with poly(dG-dC).poly(dG-dC) or poly(dA).poly(dT). This suggests that spermine and some spermine analogues induce structural changes specific to alternating A-T sequences.
利用荧光强度测量和稳态荧光偏振，研究了精胺和多胺类似物与溴化乙锭（EB）复合的各种碱基序列的合成多核苷酸之间的相互作用。精胺和多胺类似物取代了部分但不是全部与聚（dA-dT）·聚（dA-dT）或聚（dG-dC）·聚（dG-dC）结合的EB，这表明多胺可能使这些多核苷酸稳定在对EB亲和力降低的构象中。精胺脂肪族主链的修饰对其从聚（dA-dT）·聚（dA-dT）取代EB的能力有显著影响，但对从聚（dG-dC）·聚（dG-dC）取代EB的能力没有影响。当精胺和部分但不是全部的多胺类似物与EB和聚（dA-dT）·聚（dA-dT）的复合物相互作用时，会引起荧光去极化。然而，精胺及其任何类似物都不会在EB与聚（dG-dC）·聚（dG-dC）或聚（dA）·聚（dT）的复合物中诱导荧光去极化。这表明精胺和一些精胺类似物会诱导特定于交替A-T序列的结构变化。
