Bastos de Oliveira Francisco Meirelles, Kim Dongsung, Cussiol José Renato, Das Jishnu, Jeong Min Cheol, Doerfler Lillian, Schmidt Kristina Hildegard, Yu Haiyuan, Smolka Marcus Bustamante
Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.
Department of Biological Statistics and Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.
Mol Cell. 2015 Mar 19;57(6):1124-1132. doi: 10.1016/j.molcel.2015.01.043. Epub 2015 Mar 5.
The Mec1/Tel1 kinases (human ATR/ATM) play numerous roles in the DNA replication stress response. Despite the multi-functionality of these kinases, studies of their in vivo action have mostly relied on a few well-established substrates. Here we employed a combined genetic-phosphoproteomic approach to monitor Mec1/Tel1 signaling in a systematic, unbiased, and quantitative manner. Unexpectedly, we find that Mec1 is highly active during normal DNA replication, at levels comparable or higher than Mec1's activation state induced by replication stress. This "replication-correlated" mode of Mec1 action requires the 9-1-1 clamp and the Dna2 lagging-strand factor and is distinguishable from Mec1's action in activating the downstream kinase Rad53. We propose that Mec1/ATR performs key functions during ongoing DNA synthesis that are distinct from their canonical checkpoint role during replication stress.
Mec1/Tel1激酶（人类的ATR/ATM）在DNA复制应激反应中发挥着多种作用。尽管这些激酶具有多功能性，但对其体内作用的研究大多依赖于一些已被充分证实的底物。在这里，我们采用了一种基因-磷酸化蛋白质组学相结合的方法，以系统、无偏见和定量的方式监测Mec1/Tel1信号传导。出乎意料的是，我们发现Mec1在正常DNA复制过程中高度活跃，其水平与复制应激诱导的Mec1激活状态相当或更高。Mec1的这种“复制相关”作用模式需要9-1-1夹子和Dna2后随链因子，并且与Mec1激活下游激酶Rad53的作用不同。我们提出，Mec1/ATR在正在进行的DNA合成过程中执行关键功能，这些功能与其在复制应激期间的经典检查点作用不同。
