Analysis of the newly discovered control of HSV-1 replication by the PP2A B-type subunit PR130

许多化疗药物诱导DNA复制应激，导致检查点激酶的激活。它们控制着细胞周期和基因组的完整性。申请人Krämer证明了磷酸酶2a (PP2A) b亚基PR130/PPP2R3A控制检查点激酶的激活，从而控制应激细胞的命运。DNA复制压力、DNA损伤和检查点激酶的激活也是病毒感染的后果。由于尚不清楚PP2A-PR130复合体是否影响病毒诱导的检查点激酶激活和病毒复制，我们（申请人Krämer和Henke）已经开发并成功开展了一个研究项目。Henke教授从事病毒与宿主细胞相互作用特性的研究已有20多年。多年来，我们一直以此为基础进行合作。我们在PR130上进入了新的科学领域。1型单纯疱疹病毒（HSV-1）在细胞核内复制其DNA基因组。我们的数据首次表明，PR130抑制HSV-1复制，并且在这种情况下，PR130调节磷酸化和检查点激酶的稳定性。我们的目的是阐明PR130及其对检查点激酶的影响在多大程度上调节HSV-1诱导的细胞周期变化和DNA修复机制。为此，我们的目标是使用与感染事件相关的细胞系统和CRISPR-Cas9方法。此外，我们发现感染HSV-1会降低PR130的表达。我们想研究这是否是一种促进病毒复制的新机制。利用蛋白质组学分析，我们还想确定哪些细胞和病毒蛋白被PP2A-PR130复合体去磷酸化并控制其稳定性，以及这些过程如何决定病毒复制。我们还将研究临床应用的现代检查点激酶抑制剂如何影响依赖于PR130的病毒复制。基于未发表的进一步数据，我们还想分析PP2A b亚基B56β对HSV-1复制的影响。迄今为止，没有关于PR130和B56β是否影响HSV-1复制和传播的出版物。因此，我们的分析将大大扩展现有的数据。计划中的研究项目的临床意义源于1型单纯疱疹病毒在世界范围内普遍存在这一事实。世卫组织估计，2016年，约有37亿50岁以下的人感染了1型单纯疱疹病毒，全球流行率为66.6%，对应用的抗病毒药物的耐药性日益增加。因此，我们计划的基于宿主细胞靶向治疗的项目具有潜在的高社会经济和社会政治价值。

Many chemotherapeutic agents induce DNA replication stress, leading to the activation of checkpoint kinases. These control the cell cycle and genomic integrity. The applicant Krämer demonstrated that the phosphatase-2A (PP2A) B-subunit PR130/PPP2R3A controls the activation of checkpoint kinases and thus the fate of stressed cells. DNA replication stress, DNA damage, and activation of checkpoint kinases are also consequences of viral infections. Since it is unknown whether the PP2A-PR130 complex affects virus-induced checkpoint kinase activation and viral replication, we (applicants Krämer and Henke) have developed and successfully worked on a research project. Prof. Henke has been doing research on the characterization of virus-host cell interactions for more than 20 years. Our cooperation has been based on this for many years. We have entered new scientific territory on PR130. Herpes simplex virus type 1 (HSV-1) replicates its DNA genome in the nucleus. Our data show for the first time that PR130 suppresses HSV-1 replication and that PR130 regulates phosphorylation and stability of checkpoint kinases in this context. We aim to clarify the extent to which PR130 and its effects on checkpoint kinases modulate cell cycle changes and DNA repair mechanisms that are induced by HSV-1. For this, we aim to use cell systems relevant to infection events and the CRISPR-Cas9 method. In addition, we see that infection with HSV-1 reduces the expression of PR130. We want to investigate whether this is a novel mechanism that promotes viral replication. Using proteomics analyses, we would additionally like to determine which cellular and viral proteins are dephosphorylated and controlled in their stability by the PP2A-PR130 complex and how these processes determine viral replication. We will also investigate how clinically applicable modern checkpoint kinase inhibitors affect viral replication dependent on PR130. Based on further, also unpublished data, we additionally want to analyze an influence of the PP2A B-subunit B56β on HSV-1 replication. To date, no publications exist on whether PR130 and B56β influence HSV-1 replication and spread. Therefore, our analyses will significantly extend the existing data. The clinical relevance of the planned research project stems from the fact that HSV-1 is prevalent worldwide. The WHO estimates that in 2016, approximately 3.7 billion people under the age of 50 had HSV-1 infection, with a global prevalence of 66.6% and an increasing development of resistance to applied anti-viral drugs. Therefore, our planned project based on host cell targeted therapy has a potentially high socio-economic and socio-political value.