携带脉冲标记RNA的染色质组分的表征。1. 新生RNA、RNA聚合酶B和转录DNA序列含量。

Characterisation of a chromatin fraction bearing pulse-labelled RNA. 1. Nascent RNA, RNA polymerase B and transcribed DNA sequence content.

作者信息

Faber A J, Cook A, Hancock R

出版信息

Eur J Biochem. 1981 Nov;120(2):357-61. doi: 10.1111/j.1432-1033.1981.tb05712.x.

DOI:10.1111/j.1432-1033.1981.tb05712.x

Abstract

We have further characterised a fraction of polynucleosomal chromatin from mouse cells which is enriched in transcribing regions, after separation by multistep partition in a dextran /poly(ethylene glycol) two-phase mixture [Faber, A. J. (1972) Methods Cell Biol. 16, 447--457]. This fraction contains an average of 16% of the total DNA and 63% of the 3-min pulse-labelled RNA in chromatin which, by a number of criteria, represents nascent RNA transcripts. Of the total transcribing RNA polymerase B molecules in chromatin, 52% are found in this fraction by titration with radioactive alpha-amanitin. About 28% of the single-copy DNA sequences in this fraction hybridise to nuclear polyadenylated RNA, compared with only 1.5% of the single-copy sequences in the remaining (nontranscribing) chromatin fraction.

摘要

我们进一步对从小鼠细胞中分离出的一部分多聚核小体染色质进行了特性分析。该部分染色质在葡聚糖/聚（乙二醇）两相混合物中通过多步分配分离后，富含转录区域[法伯，A. J.（1972年）《细胞生物学方法》16卷，447 - 457页]。这部分染色质平均包含染色质中总DNA的16%以及3分钟脉冲标记RNA的63%，根据多项标准，这些RNA代表新生RNA转录本。通过用放射性α-鹅膏蕈碱滴定发现，染色质中总转录RNA聚合酶B分子的52%存在于该部分。与其余（非转录）染色质部分中仅1.5%的单拷贝序列相比，该部分中约28%的单拷贝DNA序列与核多聚腺苷酸化RNA杂交。