An ATR- and Cdc7-dependent DNA damage checkpoint that inhibits initiation of DNA replication
An ATR- and Cdc7-dependent DNA damage checkpoint that inhibits initiation of DNA replication
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DOI：
10.1016/s1097-2765(02)00799-2
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发表时间：
2003-01-01
期刊：
影响因子：
16
通讯作者：
Gautier, J
中科院分区：
文献类型：
--
作者：
Costanzo, V;Shechter, D;Gautier, J
我们分析了单链DNA缺口如何影响爪蟾卵提取物中的DNA复制。由DNA拓扑异构酶11抑制剂依托泊苷或核酸外切酶处理产生的DNA损伤激活DNA损伤检查点，其阻断质粒和染色体DNA复制的起始。检查点被咖啡因废除，需要ATR，但不是ATM，蛋白激酶。DNA合成的阻断是由于Cdc 7/Dbf 4蛋白激酶活性的抑制以及随后Cdc 45无法与染色质结合。检查点不需要预RC组装，但需要在染色质上加载单链结合蛋白RPA。这是靶向Cdc 7/Dbf 4蛋白激酶的DNA损伤检查点的生物化学证明。
We have analyzed how single-strand DNA gaps affect DNA replication in Xenopus egg extracts. DNA lesions generated by etoposide, a DNA topoisomerase 11 inhibitor, or by exonuclease treatment activate a DNA damage checkpoint that blocks initiation of plasmid and chromosomal DNA replication. The checkpoint is abrogated by caffeine and requires ATR, but not ATM, protein kinase. The block to DNA synthesis is due to inhibition of Cdc7/Dbf4 protein kinase activity and the subsequent failure of Cdc45 to bind to chromatin. The checkpoint does not require pre-RC assembly but requires loading of the single-strand binding protein, RPA, on chromatin. This is the biochemical demonstration of a DNA damage checkpoint that targets Cdc7/Dbf4 protein kinase.