Fractionation and characterization of DNA at sites of replication from rat liver nuclei.
Fractionation and characterization of DNA at sites of replication from rat liver nuclei.
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大鼠肝细胞核复制位点 DNA 的分离和表征。
DOI：
10.1016/0014-4827(83)90135-0
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发表时间：
1983
影响因子：
3.7
通讯作者：
Kaufmann,WK
中科院分区：
文献类型：
--
作者：
Kaufman,DG;Cordeiro-Stone,M;Rude,TH;Nelson,KG;Kaufmann,WK
再生的大鼠肝细胞核在Cs2SO4梯度中超声和离心后被分成三个不同的条带。根据这些带的密度，将其命名为轻带(Lb)、中带(MB)和重带(Hb)。Lb和MB由不同电子密度的大颗粒组成，但Lb也含有核膜残留物。当用凝胶电泳法分析时，LB和MB显示了35条以上的蛋白质条带。第三组分Hb主要由小的染色质纤维组成，其蛋白质主要是核小体核心颗粒的四个组蛋白。在体内用[~3H]胸腺嘧啶核苷短脉冲作用后，Lb和MB中DNA的比活力显著高于Hb中的整体DNA。当标记间隔的持续时间超过30min时，所有三个组分中的DNA都被同等地标记。用1.7%丙烯酰胺-0.5%琼脂糖凝胶对新合成的DNA进行了分析鉴定。在体内标记1分钟后，来自LB和MB的快速标记的DNA中有17%像从FROME复制的叉子一样固定在凝胶起源处。但只有3%的Hb DNA的迁移率为零。电子显微镜证实在Lb、MB和Hb中存在DNA复制叉。随着合成时间的延长，在所有三个组分中显示零迁移率的标记DNA的比例都有所下降。DNA变性或用S1核酸酶消化单链DNA会从凝胶中释放出新合成的DNA。核糖核酸酶无效。从LB和MB中回收的DNA也比Hb DNA的相对分子质量高。综上所述，这些结果表明：(1)Lb和MB富含在新复制的DNA中；(2)在Lb和MB中新复制的DNA的比例增加与DNA复制叉有关；(3)在Lb和MB中恢复的复制DNA可能与其他核成分原位相关，因为这种DNA似乎受到保护，不受超声作用引入染色质(HB)的更频繁的链断裂的影响。
Regenerating rat liver nuclei when sonicated and centrifuged in a Cs2SO4gradient were fractionated into three distinct bands. These bands were designated as light band (LB), middle band (MB), and heavy band (HB) according to their density. LB and MB were shown to consist of large granular particles with varying electron densities, but LB also contained remnants of nuclear membrane. When analysed by gel electrophoresis, LB and MB displayed more than 35 bands of proteins. The third fraction, HB, consisted largely of small chromatin fibers and its proteins were predominantly the four histones of the nucleosomal core particle. Following short pulses with [3H]thymidine in vivo, the specific activity of DNA in LB and MB was significantly higher than that of bulk DNA contained in HB. DNA in all three fractions became equally labelled as the duration of the labelling interval increased beyond 30 min. Newly synthesized DNA was characterized by electrophoresis on analytical 1.7% acrylamide-0.5% agarose composite gels. After a 1-min labelling interval in vivo, 17% of the rapidly labelled DNA from LB and MB was stationary at the gel origin like replication forks fromE. coli, but only 3% of HB DNA had zero mobility. Electron microscopy confirmed the presence of DNA replication forks in LB, MB, and HB. With increasing time of synthesis the proportion of labelled DNA exhibiting zero mobility decreased in all three fractions. Denaturation of DNA or digestion of single-stranded DNA with S1nuclease released newly synthesized DNA from the gel origin. Ribonuclease was without effect. DNA recovered from LB and MB also had a higher molecular weight than the HB DNA. Together these results indicate (1) that LB and MB are enriched in newly replicated DNA; (2) that an increased proportion of newly replicated DNA in LB and MB is associated with DNA replication forks; and (3) that the replicating DNA recovered in LB and MB may be associated with other nuclear constituents in situ because this DNA appears to be protected from the more frequent chain breaks introduced into the bulk of chromatin (HB) by sonication.
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[125] 核酸分子电子显微镜中的单层技术
影响因子：
--
作者：
A. Kleinschmidt
通讯作者：
A. Kleinschmidt
HeLa 细胞核 DNA 复制酶系统的解离和重建。
DOI：
10.1016/0005-2787(76)90105-2
发表时间：
1976
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
S. Seki;G. Mueller
通讯作者：
G. Mueller
由分离的肝细胞核产生的双氧核糖核酸的性质。
DOI：
10.1016/0005-2787(72)90327-9
发表时间：
1972
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
W. Lynch;T. Umeda;M. Uyeda;I. Lieberman
通讯作者：
I. Lieberman
一种在 CS2SO4 平衡密度梯度上分离大鼠肝细胞核的方法。
影响因子：
2.9
作者：
V. Genta;D. Kaufman;W. Kaufmann
通讯作者：
W. Kaufmann
DOI：
10.1083/jcb.73.3.616
发表时间：
1977-06
期刊：
The Journal of cell biology
影响因子：
--
作者：
Berezney R;Coffey DS
通讯作者：
Coffey DS