Thomas Corey, Green Sydney, Kimball Lily, Schmidtke Isaiah R, Rothwell Lauren, Griffin Makayla, Par Ivy, Schobel Sophia, Palacio Yayleene, Towle-Weicksel Jamie B, Weicksel Steven E
Department of Physical Sciences, Rhode Island College, Providence, Rhode Island, United States of America.
Department of Biology and Biological Sciences, Bryant University, Smithfield, Rhode Island, United States of America.
PLoS One. 2025 Apr 29;20(4):e0321886. doi: 10.1371/journal.pone.0321886. eCollection 2025.
DNA Polymerase Theta (Pol θ) is a conserved an A-family polymerase that plays an essential role in repairing double strand breaks, through micro-homology end joining, and bypassing DNA lesions, through translesion synthesis, to protect genome integrity. Despite its essential role in DNA repair, Pol θ is inherently error-prone. Recently, key loop regions were identified to play an important role in key functions of Pol θ. Here we present a comparative structure-function study of the polymerase domain of zebrafish and human Pol θ. We show that these two proteins share a large amount of sequence and structural homology. Using a classical biochemical approach we observe that zebrafish Pol θ displays behavior characteristic of human Pol θ, including DNA template extension in the presence of different divalent metals, microhomology-mediated end joining, and translesion synthesis. These results will support future studies looking to gain insight into Pol θ function on the basis of evolutionarily conserved features.
DNA聚合酶θ（Pol θ）是一种保守的A家族聚合酶，在通过微同源末端连接修复双链断裂以及通过跨损伤合成绕过DNA损伤以保护基因组完整性方面发挥着重要作用。尽管Pol θ在DNA修复中起着至关重要的作用，但其本身容易出错。最近，关键环区被确定在Pol θ的关键功能中发挥重要作用。在此，我们展示了斑马鱼和人类Pol θ聚合酶结构域的比较结构-功能研究。我们表明这两种蛋白质具有大量的序列和结构同源性。使用经典的生化方法，我们观察到斑马鱼Pol θ表现出人类Pol θ的行为特征，包括在不同二价金属存在下的DNA模板延伸、微同源介导的末端连接和跨损伤合成。这些结果将支持未来基于进化保守特征深入了解Pol θ功能的研究。
