Degradation of the ribosomal genes by DNAse I in Physarum polycephalum.
Degradation of the ribosomal genes by DNAse I in Physarum polycephalum.
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多头绒泡菌中 DNAse I 对核糖体基因的降解。
DOI：
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
Richard Braun
中科院分区：
文献类型：
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作者：
Jürg Stalder;Thomas Seebeck;Richard Braun
用DNA酶I处理多头绒泡菌的细胞核，当在变性条件下在凝胶上分析时，会产生具有10个核苷酸倍数的规则模式的DNA片段，这与其他真核生物一样。来自Weintraub和阿克塞尔的报告得出结论，活性基因优先被DNA酶I消化。当绒泡菌染色质被DNA酶I降解时，核糖体基因不再可用于与19-S和26-S rRNA杂交，因此优先被破坏。在有丝分裂中，没有rRNA合成的细胞核和在rRNA合成最大的G2晚期的细胞核中，染色质的降解导致相同比例的核糖体序列丢失用于杂交。因此，DNA酶I优先降解绒泡菌核糖体基因可能并不反映这些基因的实际瞬时活性。这表明DNA酶I处理可以区分活性染色质和非常强烈抑制的染色质。
Treatment of nuclei from Physarum polycephalum with DNAse I leads to DNA fragments with a regular pattern of multiples of 10 nucleotides, when analyzed on gels under denaturing conditions as has been shown for other eukaryotes. Reports from Weintraub and Axel lead to the conclusion, that active genes are preferentially digested by DNAse I. When Physarum chromatin is degraded by DNAse I, the ribosomal genes are no longer available for hybridization with 19-S and 26-S rRNA and are thus preferentially destroyed. Degradation of chromatin from nuclei in mitosis, where no rRNA is synthesized and from nuclei in late G2 phase, where rRNA synthesis is maximal, leads to the same proportion of the ribosomal sequences being lost for hybridization. Therefore the preferential degradation of the ribosomal genes in Physarum by DNAse I probably does not reflect the actual momentary activity of these genes. This suggests that DNAse I treatment may distinguish between active chromatin and very strongly repressed chromatin.