Induction of the Z conformation in poly(dG-dC).poly(dG-dC) by binding of N-2-acetylaminofluorene to guanine residues.
Induction of the Z conformation in poly(dG-dC).poly(dG-dC) by binding of N-2-acetylaminofluorene to guanine residues.
复制标题
通过 N-2-乙酰氨基芴与鸟嘌呤残基的结合诱导聚 (dG-dC).聚 (dG-dC) 中的 Z 构象。
DOI：
10.1073/pnas.78.3.1451
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发表时间：
1981
影响因子：
11.1
通讯作者：
Rich,A
中科院分区：
文献类型：
--
作者：
Santella,RM;Grunberger,D;Weinstein,IB;Rich,A
保利(dG-dC)。poly（dG- dc）和poly（dG）。用n -乙酰氧基- n -2-乙酰氨基芴修饰poly(dC)，用圆二色性和核酸酶S1酶切敏感性检测其构象。聚（dG-dC）样品。在脱氧鸟苷残基的C(8)位上用乙酰氨基芴（AAF）修饰28%的聚（dG-dC）显示出具有未修饰聚（dG-dC）的Z构象特征的圆二色光谱。聚（dG-dC）在高乙醇或盐浓度下。聚（dG-dC）样品。经AAF修饰3%的poly（dG-dC）表现出B型DNA的光谱特征。然而，它在乙醇浓度低于转化未修饰的聚（dG-dC）所需的条件下转化为Z型。聚（dG-dC）从B型到Z型。保利(dG)。poly（dC）在高乙醇浓度下不发生B-to-Z转变，在高AAF修饰下没有表现出任何大的构象变化。对核酸酶S1消化的敏感性也表明两种修饰的多核苷酸在构象上存在差异。保利(dG-dC)。经AAF修饰28%的poly（dG-dC）几乎完全抵抗核酸酶S1的酶切。然而，聚（dG）。poly（dC）和经过AAF修饰的DNA对核酸酶S1的酶切非常敏感。根据其位置是在嘌呤-嘧啶交替序列中还是在随机序列DNA中，提出了两种不同的aaf修饰脱氧鸟苷构象。
Poly(dG-dC).poly(dG-dC) and poly(dG).poly(dC) were modified by treatment with N-acetoxy-N-2-acetylaminofluorene, and their conformations were examined by circular dichroism and susceptibility to nuclease S1 digestion. A sample of poly(dG-dC).poly(dG-dC) modified to an extent of 28% with acetylaminofluorene (AAF) at the C(8) position of the deoxyguanosine residues showed a circular dichroism spectrum that had the characteristics of the Z conformation seen in unmodified poly(dG-dC).poly(dG-dC) at high ethanol or salt concentrations. A sample of poly(dG-dC).poly(dG-dC) modified only 3% by AAF showed a spectrum characteristic of the B form of DNA. However, it was converted to the Z form at ethanol concentrations lower than required to convert unmodified poly(dG-dC).poly(dG-dC) from the B to the Z form. Poly(dG).poly(dC), which does not undergo the B-to-Z transition at high ethanol concentrations, did not show any large conformational changes with high AAF modification. Susceptibility to digestion with nuclease S1 also suggested differences in the conformations of the two modified polynucleotides. Poly(dG-dC).poly(dG-dC) modified by AAF to an extent of 28% was almost completely resistant to nuclease S1 digestion. However, both poly(dG).poly(dC) and DNA modified to similar levels by AAF were highly susceptible to nuclease S1 digestion. Two different conformations for AAF-modified deoxyguanosine are proposed, depending on whether its position is in alternating purine-pyrimidine sequences or in random-sequence DNA.