期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1974
卷号：71
期号：6
页码：2193-2197
DOI：10.1073/pnas.71.6.2193
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A fraction of rat-liver chromatin that is transcriptionally active in vivo has been purified 6- to 7-fold over whole chromatin. This was accomplished by selectively shearing chromatin with DNase II followed by fractionating the released portion on the basis of its solubility properties in 2 mM MgCl2. The resulting soluble material comprises 11% of the total chromatin DNA and is impoverished in histone and enriched in nonhistone protein. Compared with unsheared chromatin, this minor fraction exhibits marked differences in chromosomal protein species. DNA renaturation studies indicate that this fraction is composed of a specific subset of whole genomal DNA sequences. Furthermore, DNA{middle dot}RNA hybridization experiments suggest that almost 60% of the nonrepetitious DNA sequences of this minor fraction could code for cellular RNA.
关键词：chromatin fractionation ; DNase II ; DNA·RNA hybridization
