Noncatalytic, N-terminal Domains of DNA Polymerase Lambda Affect Its Cellular Localization and DNA Damage Response.
Noncatalytic, N-terminal Domains of DNA Polymerase Lambda Affect Its Cellular Localization and DNA Damage Response.
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DNA 聚合酶 Lambda 的非催化 N 端结构域影响其细胞定位和 DNA 损伤反应。
DOI：
10.1021/acs.chemrestox.7b00067
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发表时间：
2017
影响因子：
4.1
通讯作者：
Suo,Zucai
中科院分区：
文献类型：
--
作者：
Stephenson,AnthonyA;Taggart,DavidJ;Suo,Zucai
特殊的 DNA 聚合酶，例如 DNA 聚合酶 lambda (Polλ)，在 DNA 损伤耐受和修复途径中发挥着重要作用。了解 DNA 聚合酶如何被调节并被招募到 DNA 损伤位点对于理解这些途径至关重要。最近的研究表明，Polλ 在几种不同的 DNA 损伤耐受和修复途径中发挥作用。在本文中，我们报告了人类 Polλ N 端结构域在调节其参与 DNA 损伤耐受和修复方面的先前未知的作用。通过使用蛋白质印迹分析、荧光显微镜和细胞存活测定，我们发现 Polλ 的 BRCA1 C 末端 (BRCT) 和富含脯氨酸/丝氨酸 (PSR) 结构域影响其细胞定位和 DNA 损伤反应。 Polλ的核定位信号（NLS）对于克服其BRCT和PSR结构域造成的核定位障碍是必要的。 DNA 损伤的诱导导致 Polλ 募集到染色质，这由其 BRCT 和 PSR 结构域控制。此外，这两个结构域的存在都是 Polλ 介导的对氧化性 DNA 损伤的耐受所必需的，而不是 DNA 甲基化损伤的耐受性。这些发现表明 Polλ 的 N 末端结构域对于调节其对 DNA 损伤的反应非常重要。
Specialized DNA polymerases, such as DNA polymerase lambda (Polλ), are important players in DNA damage tolerance and repair pathways. Knowing how DNA polymerases are regulated and recruited to sites of DNA damage is imperative to understanding these pathways. Recent work has suggested that Polλ plays a role in several distinct DNA damage tolerance and repair pathways. In this paper, we report previously unknown roles of the N-terminal domains of human Polλ for modulating its involvement in DNA damage tolerance and repair. By using Western blot analysis, fluorescence microscopy, and cell survival assays, we found that the BRCA1 C-terminal (BRCT) and proline/serine-rich (PSR) domains of Polλ affect its cellular localization and DNA damage responses. The nuclear localization signal (NLS) of Polλ was necessary to overcome the impediment of its nuclear localization caused by its BRCT and PSR domains. Induction of DNA damage resulted in recruitment of Polλ to chromatin, which was controlled by its BRCT and PSR domains. In addition, the presence of both domains was required for Polλ-mediated tolerance of oxidative DNA damage but not DNA methylation damage. These findings suggest that the N-terminal domains of Polλ are important for regulating its responses to DNA damage.