Kharchenko E P, Miul'berg A A, Tishchenko L I, Borisova E A
Biokhimiia. 1982 May;47(5):713-23.
The binding of the antibiotic dyes to chromatin fragmented by various ways and to preparations of "complete" (MH3, 206 DNA base pairs) and "minor" MH1, 155 DNA base pairs) nucleosomes was studied. The latter were obtained from the total hydrolysate of nuclear chromatin hydrolysis by Ca-Mg-dependent endonuclease, using preparative electrophoresis in polyacrylamide gel. In liver chromatin of different vertebrate species the actinomycin D binding is decreased by 70% as compared to DNA binding, while that of ethidium bromide is reduced only by 40%. The splitting of part of internucleosomal DNA by Ca-Mg-dependent endonuclease further decreases the number of binding sites for ethidium bromide, but not for actinomycin D. MH3 bid 24 molecules of actinomycin D per 10(3) of nucleotides; their DNA contain 43.4% of GC-pairs. The GC content in MH1 is 47.7%; they bind 28 dye molecules per 10(3) of nucleotides. The data obtained are discussed in terms of possible predominant localization of nucleosomal cores in GC-pair-rich DNA sites.
研究了抗生素染料与通过各种方式断裂的染色质以及“完整”（MH3，206个DNA碱基对）和“微小”（MH1，155个DNA碱基对）核小体制剂的结合情况。后者是通过Ca-Mg依赖性核酸内切酶对核染色质进行水解，然后利用聚丙烯酰胺凝胶制备电泳从总水解产物中获得的。在不同脊椎动物物种的肝脏染色质中，与DNA结合相比，放线菌素D的结合减少了70%，而溴化乙锭的结合仅减少了40%。Ca-Mg依赖性核酸内切酶对部分核小体间DNA的切割进一步减少了溴化乙锭的结合位点数量，但对放线菌素D的结合位点数量没有影响。MH3每10³个核苷酸结合24个放线菌素D分子；其DNA含有43.4%的GC对。MH1中的GC含量为47.7%；它们每10³个核苷酸结合28个染料分子。根据核小体核心在富含GC对的DNA位点可能的主要定位对所得数据进行了讨论。
