Project 1: Base Repair: Molecular response to base-modifying chemotherapeutic agents

综述-项目1：碱基修饰化疗药物的分子反应 修复DNA上的碱基损伤是至关重要的，因为这种损伤既是遗传毒性的，也是突变的。许多 用于癌症治疗的化疗药物，如顺铂和烷化剂，会导致这种类型的 这是最常用的治疗方法之一，强调了它们的临床意义。 虽然细胞对含有碱基损伤的DNA的反应已知很多，但RNA损伤的重要性 直到最近才变得越来越受重视。事实上，据估计，烷基化的rna由大量的 用这种试剂处理的细胞中的大多数受损的核酸。难怪细胞已经有了 进化出一系列机制来应对受损的RNA。我们发现ALKBH3-ASCC 修复复合体介导细胞对DNA和RNA碱基损伤的反应。这个综合体还连接着 通过一种新的RNA发出先天免疫或潮湿(损伤相关的分子模式)信号 内切酶活性，这是我们最近通过这个项目的多学科努力而发现的 项目。我们的工作表明，RNA损伤识别和信号传递是细胞反应中的关键节点 基地损坏，一个未被开发的区域，我们试图在这次续签申请中了解到这一点。具体来说，我们 将使用结构方法和生物化学相结合的方法来揭示酶的机制基础 ALKBH3-ASCC复合体内的活动(目标1)。我们还将确定ASCC中介的重要性， RNA依赖的DAMP信号在常用化疗药物反应中的作用及其在细胞中的作用 命运决定(目标2)。最后，我们将确定ALKBH3-ASCC途径如何与已建立的 碱基修复途径，潜在地识别这些之间的新的相加或合成致死关系 路径(目标3)。总之，拟议的工作也将揭示对RNA贡献的重要见解 作为DNA碱基损伤反应及其与肿瘤细胞根除的相关性。

SUMMARY - PROJECT 1: Molecular response to base-modifying chemotherapeutic agents Repair of base damage on DNA is critical because such damage is both genotoxic and mutagenic. Many chemotherapeutic agents used for cancer therapy, such as cisplatin and alkylating agents, induce this type of damage and are one of the most commonly used modalities for treatment, underscoring their clinical significance. While much is known about how cells respond to DNA containing base damage, the importance of RNA damage has become increasingly appreciated only recently. Indeed, alkylated RNA is estimated to comprise the vast majority of the damaged nucleic acid in cells treated with such agents. It is not surprising then that cells have evolved a number of mechanisms to cope with damaged RNA. We have discovered that the ALKBH3-ASCC repair complex mediates the cellular response to DNA as well RNA base damage. This complex also interfaces with the innate immune or DAMP (damage-associated molecular pattern) signaling through a novel RNA endonuclease activity, which we have recently uncovered through the multidisciplinary efforts of this program project. Our work implicates RNA damage recognition and signaling as a critical node in the cellular response to base damage, an underexplored area, which we seek to understand in this renewal application. Specifically, we will use a combination of structural methods and biochemistry to reveal the mechanistic basis of the enzymatic activities within the ALKBH3-ASCC complex (Aim 1). We will also determine the importance of ASCC-mediated, RNA-dependent DAMP signaling in the response to commonly used chemotherapeutic agents and its role in cell fate decisions (Aim 2). Finally, we will determine how the ALKBH3-ASCC pathway integrates with established base repair pathways, potentially identifying novel additive or synthetic lethal relationships between these pathways (Aim 3). Together, the proposed work will reveal important insights into the contribution of RNA as well as DNA base damage responses and its relevance to tumor cell eradication.