In vitro transcription by Xenopus oocytes RNA polymerase III requires a DNA topoisomerase II activity.
In vitro transcription by Xenopus oocytes RNA polymerase III requires a DNA topoisomerase II activity.
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爪蟾卵母细胞 RNA 聚合酶 III 的体外转录需要 DNA 拓扑异构酶 II 活性。
DOI：
10.1002/j.1460-2075.1986.tb04189.x
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
D. Blangy
中科院分区：
文献类型：
--
作者：
G. Glikin;D. Blangy
非洲爪蟾卵母细胞提取物在体外添加ATP和Mg2+后能够组装小染色体。我们跟踪了多瘤病毒封闭环状DNA的体外超卷曲和转录的时间过程。在ATP和Mg2+存在的情况下，转录活性随着染色质组装时间的延长而增加，而在不存在ATP和Mg2+的情况下，只检测到残留活性。我们还发现，多瘤DNA和5S RNA基因转录主要由RNA聚合酶III进行。另一方面，新生物素抑制了多瘤RNA和5S RNA的合成，这表明转录起始需要DNA拓扑异构酶II或DNA旋切酶活性。
Extracts of Xenopus laevis oocytes are able to assemble minichromosomes in vitro when they are supplemented with ATP and Mg2+. We have followed the time course of in vitro DNA supercoiling and transcription of polyoma virus closed circular DNA. The transcriptional activity increased with the assembly time of chromatin in the presence of both ATP and Mg2+, but only residual activity was detected in the absence of either of them. We also found that polyoma DNA as well as 5S RNA gene transcription were carried out mainly by an RNA polymerase III. On the other hand, polyoma RNA and 5S RNA synthesis were inhibited by novobiocin in a way that suggested the requirement of a DNA topoisomerase II or DNA gyrase activity for the initiation of transcription.