XRN2-DDX23 Cooperation in Avoiding R-loop-induced Genomic Instability

XRN2-DDX23 合作避免 R 环引起的基因组不稳定

• 批准号: 10654331
• 负责人: Praveen Patidar
• 金额: $ 35.56万
• 依托单位: NEW MEXICO INST OF MINING & TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-18 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10654331
• 关键词: 5' -exoribonuclease; Autoimmune Diseases; Binding; Biochemical; Biological; Biology; Cell Cycle Regulation; Cell Survival; Cells; Code; DNA; DNA Damage; DNA Double Strand Break; DNA Repair; DNA replication fork; Data; Defect; Detection; Disease; Double Strand Break Repair; Ensure; Enzymes; Exoribonucleases; Gene Silencing; Genes; Genetic Polymorphism; Genome; Genomic Instability; Goals; Health; Homeostasis; Human; Hybrids; Impairment; Individual; Link; Maintenance; Malignant Neoplasms; Malignant neoplasm of lung; Mediating; Metabolism; Molecular; Mutation; Neurodegenerative Disorders; Nonhomologous DNA End Joining; Nuclear; Pathway interactions; Poly(ADP-ribose) Polymerases; Proteins; RNA; RNA Degradation; RNA Helicase; RNA Polymerase II; RNA metabolism; Regulation; Research; Research Proposals; Resolution; Ribosomal RNA; Risk; Role; Single-Stranded DNA; Site; Source; Spliceosomes; Testing; U5 Small Nuclear Ribonucleoprotein; aspartylglutamate; enzyme deficiency; genetic information; genome integrity; genome-wide; glutamylalanine; helicase; innovation; insight; mRNA Expression; novel; nucleic acid structure; preservation; prevent; programs; replication stress; response; sensor; termination factor; transcription termination; transmission process

Project Summary Compromised genomic integrity results in several debilitating diseases such as neurodegenerative disorders, autoimmune diseases, and cancer. Persistent nucleic acid structures containing RNA-DNA hybrids with a displaced single-stranded DNA (R-loops) are a potent source of genomic instability. One of the major sources of R-loops is impaired regulation of RNA polymerase II (RNAPII) at transcription termination sites of protein coding genes. In humans, the 5’-3’-exoribonuclease 2 (XRN2) is essential for genome-wide timely termination of RNAPII downstream of poly(A) sites. In essence, XRN2’s role in RNA metabolism is well understood. However, its role in genome maintenance remains elusive and there is lack of functional information regarding its molecular contributions in coordinating DNA repair, resolving replication stress, and promoting cell survival. Our long-term research goal is to define the roles of transcription termination factors including XRN2, in preventing R-loop-induced genomic instability and identify avenues to target their vulnerabilities. For this research program, we will primarily focus on delineating the interplay of XRN2 and DEAD (Asp-Glu-Ala-Asp) Box helicase 23 (DDX23). We recently defined the interactome of XRN2 and identified molecular links that connect it to DNA double-strand break (DSB) repair and cell cycle control of chromosomal replication. Our data support XRN2 and DDX23 interaction and a potential interplay of these two enzymes in R-loop metabolism and genome maintenance. We hypothesize that XRN2-DDX23 interaction enables them to cooperatively suppress R-loop-induced genomic instability and deficiencies of these enzymes engage central DNA damage sensor protein poly(ADP-ribose) polymerase 1 (PARP1) to coordinate repair of DSBs emanating from impaired R-loop homeostasis. We will pursue following specific aims to test our hypothesis; Aim 1: Determine the biochemical basis and functional implications of XRN2 and DDX23 interaction. Aim 2: Determine the biological significance of XRN2-DDX23 interplay in R-loop metabolism and genome maintenance. Collectively, our studies will provide mechanistic insights into XRN2-DDX23 cooperation in avoiding R-loop-induced genomic instability, and establish potential avenues for targeting XRN2 and DDX23 vulnerabilities.

项目摘要 受损的基因组完整性导致多种使人衰弱的疾病，例如 神经退行性疾病，自身免疫性疾病和癌症。持续的核酸 含有带移位的单链DNA（R-Loops）的RNA-DNA杂交的结构是A 基因组不稳定性的有效来源。 R环的主要来源之一是法规受损 RNA聚合酶II（RNAPII）的转录终止位点的蛋白质编码基因。在 人类，5'-3'-exoribonibonecleaseplease 2（XRN2）对于全基因组及时终止至关重要 poly（a）位点的RNAPII。本质上，XRN2在RNA代谢中的作用很好 理解。但是，其在基因组维持中的作用仍然难以捉摸，缺乏 有关其分子在协调DNA修复中的分子贡献的功能信息，解决 复制应力和促进细胞存活。我们的长期研究目标是定义角色 包括XRN2在内的转录终止因子，以防止R环诱导的基因组 不稳定并确定针对其脆弱性的途径。对于此研究计划，我们将 首先关注描述XRN2和DEAD（ASP-GLU-ALA-ASP）盒解旋酶的相互作用 23（DDX23）。我们最近定义了XRN2的相互作用组，并确定了分子链接 将其连接到DNA双链断裂（DSB）修复和染色体的细胞周期控制 复制。我们的数据支持XRN2和DDX23相互作用以及这两个的潜在相互作用 R环代谢和基因组维持中的酶。我们假设XRN2-DDX23 互动使他们能够协同抑制R环诱导的基因组不稳定性和 这些酶的缺陷与中央DNA损伤传感器蛋白聚（ADP-核糖）接合 聚合酶1（PARP1）以协调从R-loop受损的DSB进行修复 稳态。我们将追求特定的目标来检验我们的假设；目标1：确定 XRN2和DDX23相互作用的生化基础和功能意义。目标2：确定 R环代谢和基因组中XRN2-DDX23相互作用的生物学性 维护。总的来说，我们的研究将为XRN2-DDX23提供机械见解 避免R环诱导的基因组不稳定性的合作，并为 针对XRN2和DDX23漏洞。