Bailey Laura J, Doherty Aidan J
Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton BN1 9RQ, U.K.
Biochem Soc Trans. 2017 Apr 15;45(2):513-529. doi: 10.1042/BST20160162.
PrimPol, ase-ymerase), the most recently identified eukaryotic polymerase, has roles in both nuclear and mitochondrial DNA maintenance. PrimPol is capable of acting as a DNA polymerase, with the ability to extend primers and also bypass a variety of oxidative and photolesions. In addition, PrimPol also functions as a primase, catalysing the preferential formation of DNA primers in a zinc finger-dependent manner. Although PrimPol's catalytic activities have been uncovered , we still know little about how and why it is targeted to the mitochondrion and what its key roles are in the maintenance of this multicopy DNA molecule. Unlike nuclear DNA, the mammalian mitochondrial genome is circular and the organelle has many unique proteins essential for its maintenance, presenting a differing environment within which PrimPol must function. Here, we discuss what is currently known about the mechanisms of DNA replication in the mitochondrion, the proteins that carry out these processes and how PrimPol is likely to be involved in assisting this vital cellular process.
PrimPol（一种无引物酶活性的聚合酶）是最近发现的真核生物聚合酶，在核DNA和线粒体DNA维持中均发挥作用。PrimPol能够作为DNA聚合酶发挥作用，具有延伸引物的能力，还能绕过多种氧化损伤和光损伤。此外，PrimPol还作为一种引发酶发挥作用，以锌指依赖的方式催化DNA引物的优先形成。尽管PrimPol的催化活性已被揭示，但我们对其如何以及为何定位于线粒体，以及它在维持这种多拷贝DNA分子中的关键作用仍知之甚少。与核DNA不同，哺乳动物线粒体基因组是环状的，该细胞器有许多维持其功能所必需的独特蛋白质，这为PrimPol发挥作用提供了一个不同的环境。在这里，我们讨论目前已知的线粒体DNA复制机制、执行这些过程的蛋白质，以及PrimPol可能如何参与协助这一重要的细胞过程。
