4-羟基氨基喹啉1-氧化物修饰后聚（dG-dC）·聚（dG-dC）构象变化的分光光度法和免疫化学研究

Spectrophotometrical and immunochemical studies on the conformational changes in poly(dG-dC).poly(dG-dC) after modification by 4-hydroxyaminoquinoline 1-oxide.

作者信息

Tada M, Ikeda S, Suzuki M, Minoura Y, Kojima M, Morita T

机构信息

Laboratory of Biochemistry, Aichi Cancer Center, Nagoya, Japan.

出版信息

Biochim Biophys Acta. 1991 Aug 27;1090(1):29-37. doi: 10.1016/0167-4781(91)90033-i.

DOI:10.1016/0167-4781(91)90033-i

PMID:1909180

Abstract

Poly(dG-dC).poly(dG-dC) was modified by the reaction with 4-hydroxyaminoquinoline 1-oxide (4HAQO) in the presence of seryl-AMP. The conformations of 4HAQO-modified poly(dG-dC).poly(dG-dC) and of poly(dG-dC).poly(dG-dC) were studied by circular dichroism spectra under various salt concentration conditions. 4HAQO residues to guanine bases are inefficient in inducing the transition of poly(dG-dC).poly(dG-dC) from B-form to Z-form conformation. We have elicited monoclonal antibodies against 4HAQO-poly(dG-dC).poly(dG-dC). They were characterized using enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA) and binding to supercoiled DNA. These antibodies reacted with 4HAQO-poly(dG-dC).poly(dG-dC) specifically but not with 4HAQO-modified DNA or poly(dG).poly(dC). However, they cross-reacted with N-acetoxy-2-acetylaminofluorene-modified poly(dG-dC).poly(dG-dC) in Z-form conformation. These monoclonal antibodies may recognize a unique conformation in poly(dG-dC).poly(dG-dC) after 4HAQO modification.

摘要

聚（dG-dC）·聚（dG-dC）在丝氨酰-AMP存在下与4-羟基氨基喹啉1-氧化物（4HAQO）反应进行修饰。在不同盐浓度条件下，通过圆二色光谱研究了4HAQO修饰的聚（dG-dC）·聚（dG-dC）和聚（dG-dC）·聚（dG-dC）的构象。4HAQO残基与鸟嘌呤碱基结合时，诱导聚（dG-dC）·聚（dG-dC）从B型构象转变为Z型构象的效率较低。我们制备了针对4HAQO-聚（dG-dC）·聚（dG-dC）的单克隆抗体。使用酶联免疫吸附测定（ELISA）、放射免疫测定（RIA）以及与超螺旋DNA的结合对它们进行了表征。这些抗体与4HAQO-聚（dG-dC）·聚（dG-dC）特异性反应，但不与4HAQO修饰的DNA或聚（dG）·聚（dC）反应。然而，它们与Z型构象的N-乙酰氧基-2-乙酰氨基芴修饰的聚（dG-dC）·聚（dG-dC）发生交叉反应。这些单克隆抗体可能识别4HAQO修饰后聚（dG-dC）·聚（dG-dC）中的独特构象。