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

总结-项目1：对碱修饰化疗药物的分子应答 DNA碱基损伤的修复是至关重要的，因为这种损伤是遗传毒性和致突变性的。许多 用于癌症治疗的化学治疗剂，例如顺铂和烷化剂，诱导这种类型的肿瘤。 是最常用的治疗方式之一，强调了其临床意义。 虽然细胞如何对含有碱基的DNA损伤做出反应已经知道很多，但RNA损伤的重要性仍然存在。 直到最近才越来越受到重视。事实上，烷基化的RNA估计包含大量的 在用这些试剂处理的细胞中的大多数受损核酸。因此，细胞具有 进化出许多机制来科普受损的RNA。我们发现ALKBH 3-ASCC 修复复合物介导对DNA以及RNA碱基损伤的细胞应答。这个复合体还与 与先天免疫或DAMP（损伤相关分子模式）信号通过一种新的RNA 核酸内切酶活性，我们最近发现，通过多学科的努力，这一计划 项目我们的工作暗示RNA损伤识别和信号传导是细胞对 基地损害，一个未充分开发的领域，我们试图在这个更新申请中了解。我们特别 将使用结构方法和生物化学的结合来揭示酶促反应的机制基础。 ALKBH 3-ASCC复合物中的活性（目的1）。我们还将确定ASCC介导的， RNA依赖的DAMP信号在常用化疗药物应答中的作用及其在细胞凋亡中的作用 命运决定（目标2）。最后，我们将确定ALKBH 3-ASCC通路如何与已建立的 碱基修复途径，可能确定新的添加剂或合成的致命关系，这些 路径（目标3）。总之，拟议的工作将揭示重要的见解，以及RNA的贡献 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.