Portugal J, Waring M J
University of Cambridge Department of Pharmacology, England.
Biochimie. 1987 Aug;69(8):825-40. doi: 10.1016/0300-9084(87)90209-4.
Patterns of sensitivity to DNAase I cleavage have been analysed in order to investigate the effects of anti-tumour antibiotics and related drugs on nucleosome core particles containing different DNA restriction fragments. In this article, we review the experimental results which show that after controlled digestion of defined-sequence core particles, new cleavage products appear in the enzyme digestion patterns which lie approximately mid-way between the strong bands characteristic of native nucleosome core particles. The effects of the antibiotics, which include bis-intercalators as well as minor groove-binding ligands (but not monofunctional intercalators), are explained in terms of an induced change in rotational setting (phasing) of the core DNA. The new rotational positioning of DNA induced by antibiotic binding appears to be almost independent of DNA sequence, although some differences can be observed with the various pieces of DNA, most likely reflecting the exact number and disposition of antibiotic binding sites.
为了研究抗肿瘤抗生素及相关药物对含有不同DNA限制性片段的核小体核心颗粒的影响，已对DNA酶I切割的敏感性模式进行了分析。在本文中，我们回顾了实验结果，这些结果表明，在对特定序列的核心颗粒进行受控消化后，新的切割产物出现在酶切模式中，这些产物大约位于天然核小体核心颗粒特征性强条带之间的中间位置。抗生素的作用，包括双嵌入剂以及小沟结合配体（但不包括单功能嵌入剂），是根据核心DNA旋转设置（相位）的诱导变化来解释的。抗生素结合诱导的DNA新旋转定位似乎几乎与DNA序列无关，尽管在不同的DNA片段中可以观察到一些差异，这很可能反映了抗生素结合位点的确切数量和分布。
