Pugliese Kaitlin M, Weiss Gregory A
Department of Chemistry, University of California, Irvine, CA 92697, United States.
Department of Chemistry, University of California, Irvine, CA 92697, United States; Department of Molecular Biology and Biochemistry, 4122 Natural Sciences 1 (mailing: 1102 Natural Sciences 2), University of California, Irvine, CA 92697-2025, United States.
Curr Opin Chem Biol. 2017 Dec;41:43-49. doi: 10.1016/j.cbpa.2017.10.005. Epub 2017 Nov 2.
DNA polymerases must discriminate the correct Watson-Crick base pair-forming deoxynucleoside triphosphate (dNTP) substrate from three other dNTPs and additional triphosphates found in the cell. The rarity of misincorporations in vivo, then, belies the high tolerance for dNTP analogs observed in vitro. Advances over the last 10 years in single-molecule fluorescence and electronic detection of dNTP analog incorporation enable exploration of the mechanism and limits to base discrimination by DNA polymerases. Such studies reveal transient motions of DNA polymerase during substrate recognition and mutagenesis in the context of erroneous dNTP incorporation that can lead to evolution and genetic disease. Further improvements in time resolution and noise reduction of single-molecule studies will uncover deeper mechanistic understanding of this critical, first step in evolution.
DNA聚合酶必须从细胞中发现的其他三种脱氧核苷三磷酸(dNTP)和其他三磷酸中辨别出能形成正确沃森-克里克碱基对的脱氧核苷三磷酸(dNTP)底物。因此,体内错配掺入的罕见性与体外观察到的DNA聚合酶对dNTP类似物的高耐受性不符。在过去十年中,单分子荧光和dNTP类似物掺入的电子检测方面的进展,使得人们能够探索DNA聚合酶碱基识别的机制及其局限性。此类研究揭示了在错误掺入dNTP的情况下,DNA聚合酶在底物识别和诱变过程中的瞬态运动,而这种运动可能导致进化和遗传疾病。单分子研究在时间分辨率和降噪方面的进一步改进,将揭示对这一进化关键第一步的更深入机制理解。