a Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics , Karolinska Institutet , Stockholm , Sweden.
Cell Cycle. 2018;17(5):568-579. doi: 10.1080/15384101.2017.1387696. Epub 2018 Apr 2.
Incidents that slow or stall replication fork progression, collectively known as replication stress, represent a major source of spontaneous genomic instability. Here, we determine the requirement for global protein biosynthesis on DNA replication and associated downstream signaling. We study this response side by side with dNTP deprivation; one of the most commonly used means to investigate replication arrest and replicative stress. Our in vitro interrogations reveal that inhibition of translation by cycloheximide (CHX) rapidly impairs replication fork progression without decoupling helicase and polymerase activities or inducing DNA damage. In line with this, protein deprivation stress does not activate checkpoint signaling. In contrast to the direct link between insufficient dNTP pools and genome instability, our findings suggest that replication forks remain stable during short-term protein deficiency. We find that replication forks initially endure fluctuations in protein supply in order to efficiently resume DNA synthesis upon reversal of the induced protein deprivation stress. These results reveal distinct cellular responses to replication arrest induced by deprivation of either nucleotides or proteins.
事件，减缓或stall 复制叉进展，统称为复制压力，代表着自发的基因组不稳定性的一个主要来源。在这里，我们确定了对全球蛋白质生物合成的 DNA 复制和相关的下游信号的要求。我们研究这个反应并排 dNTP 剥夺;最常用的手段之一来调查复制逮捕和复制压力。我们的体外询问揭示了翻译的抑制由环己酰亚胺（CHX）迅速损害复制叉进展没有分离解旋酶和聚合酶活性或诱导 DNA 损伤。与此相一致的是，蛋白质剥夺应激不会激活检查点信号。与不足的 dNTP 池和基因组不稳定性之间的直接联系相反，我们的研究结果表明，复制叉在短期内保持稳定的蛋白质缺乏。我们发现复制叉最初忍受波动的蛋白质供应，以有效地恢复 DNA 合成后反转诱导的蛋白质剥夺应激。这些结果揭示了不同的细胞反应复制逮捕诱导的剥夺核苷酸或蛋白质。
