DNA damage by the enediyne C-1027 results in the inhibition of DNA replication by loss of replication protein A function and activation of DNA-dependent protein kinase.
DNA damage by the enediyne C-1027 results in the inhibition of DNA replication by loss of replication protein A function and activation of DNA-dependent protein kinase.
复制标题
烯二炔 C-1027 造成的 DNA 损伤会导致复制蛋白 A 功能丧失和 DNA 依赖性蛋白激酶激活，从而抑制 DNA 复制。
DOI：
10.1021/bi015680c
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发表时间：
2001
期刊：
影响因子：
2.9
通讯作者：
Melendy,T
中科院分区：
文献类型：
--
作者：
Liu,JS;Kuo,SR;Yin,X;Beerman,TA;Melendy,T
Treatment of cells with the enediyne C-1027 is highly efficient at inducing single- and double-strand DNA breaks. This agent is highly cytotoxic when used at picomolar levels over a period of days. For this study, C-1027 has been used at higher levels for a much shorter time period to look at early cellular responses to DNA strand breaks. Extracts from cells treated with C-1027 for as little as 2 h are deficient in SV40 DNA replication activity. Treatment with low levels of C-1027 (1−3 nM) does not result in the presence of a replication inhibitor in cell extracts, but they are deficient in replication protein A (RPA) function. Extracts from cells treated with high levels of C-1027 (10 nM) do show the presence of a trans-acting inhibitor of DNA replication. The deficiency in RPA in extracts from cells treated with low levels of C-1027 can be fully complemented by the addition of exogenous RPA, and may be due to a C-1027-induced decrease in the extractability of RPA. This decrease in the extractability of RPA correlates with the appearance of many extraction-resistant intranuclear RPA foci. The trans-acting inhibitor of DNA replication induced by treatment of cells with high levels of C-1027 (10 nM) is DNA-dependent protein kinase (DNA-PK). DNA-PK is activated by the presence of DNA fragments induced by C-1027 treatment, and can be abrogated by removal of the DNA fragments. Although it is activated by DNA damage and phosphorylates RPA, DNA-PK is not required for either RPA focalization or loss of RPA replication activity.
