The Role of Mono-ADP-Ribosylation by PARP14 in Radioresistance

PARP14 的单 ADP 核糖基化在放射抗性中的作用

• 批准号: 9206998
• 负责人: George Lucian Moldovan
• 金额: $ 34.07万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-01 至 2021-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9206998
• 关键词: ADP Ribose Transferases; ADP ribosylation; Address; Adenosine Diphosphate Ribose; Affect; Biochemical; Biological Assay; Cells; Cellular Assay; Clinical; DNA; DNA Damage; DNA Double Strand Break; DNA Repair; DNA Repair Gene; Development; Double Strand Break Repair; Enzymes; Excision; Family member; Genetic Recombination; Genomic approach; Hypersensitivity; Immunofluorescence Immunologic; Ionizing radiation; Lesion; Malignant Neoplasms; Measures; Mediating; Metabolism; Molecular; Mono(ADP-Ribose) Transferases; Mono-S; Mus; Mutation; Nonhomologous DNA End Joining; Outcome; Poly Adenosine Diphosphate Ribose; Post-Translational Protein Processing; Process; Proteins; Rad51 recombinase; Radiation; Radiation Induced DNA Damage; Radiation Tolerance; Radiation induced double strand break; Radiation therapy; Radiation-Sensitizing Agents; Radioresistance; Radiosensitization; Reaction; Regulation; Reporting; Resistance; Role; Testing; Toxic effect; Treatment Efficacy; Work; Xenograft procedure; base; cancer cell; cancer recurrence; cancer therapy; chromatin immunoprecipitation; clinically relevant; design; experimental study; homologous recombination; improved; inhibitor/antagonist; innovation; killings; knock-down; neoplastic cell; novel; novel therapeutics; public health relevance; radiation effect; radiation resistance; radiation response; radioresistant; radiosensitive; repaired; response; single molecule; transcriptome sequencing; treatment effect; tumor

 DESCRIPTION (provided by applicant): Ionizing Radiation kills cancer cells by generating DNA damage. Resistance to Ionizing Radiation is generally determined by DNA repair mechanisms that can repair radiation-induced DNA damage. The most toxic effect of radiation is represented by the formation of double stranded DNA breaks. These breaks can be repaired by Homologous Recombination, and Non-Homologous End Joining DNA repair mechanisms. Inhibition of these mechanisms results in increased radiosensitivity since repair of radiation-induced double strand breaks is blocked. Thus, understanding the molecular mechanisms of double strand break repair is essential for designing novel radiosensitization therapies. We have recently uncovered a novel mechanism that regulates radioresistance, centered on the protein PARP14. PARP14 is a mono-ADP-ribosyltransferase, which unlike its well-known cousin PARP1 is unable to catalyze poly-ADP-ribose chain formation but can only transfer a single molecule of ADP-ribose to substrates. Mono-ADP-ribosylation is a still mysterious post-translational modification, and its functions in the cell are poorly characterized. Or preliminary results presented here show that PARP14 promotes repair of double strand breaks by activating Homologous Recombination DNA repair. Moreover, our preliminary results presented here indicate a mechanism for this activation: PARP14 mono-ADP-ribosylates the recombination factor RAD51 to promote RAD51 removal from D-loops thus allowing D-loop extension past the break and complete the recombination reaction. Thus, our work shows that PARP14 inhibition results in radiosensitivity by downregulating Homologous Recombination-dependent repair of radiation-induced double strand DNA breaks. In this proposal, we test the hypothesis that PARP14 promotes the repair of radiation-induced double strand DNA breaks by Homologous Recombination, through RAD51 mono-ADP-ribosylation. We will employ a comprehensive, integrative approach to study: 1) the impact of PARP14 on the repair of radiation-induced DNA damage by Homologous Recombination and other DNA repair mechanisms, and 2) the role of RAD51 mono- ADP-ribosylation by PARP14 in repair of radiation-induced double strand breaks. Our study is highly innovative since it addresses a novel, previously unrecognized function of mono- ADP-ribosylation in radioresistance. Our work will unravel how mono-ADP-ribosylation by PARP14 promotes radiation resistance, and describe novel radiosensitization approaches, based on PARP14 inhibition.

 描述(申请人提供)：电离辐射通过产生DNA损伤来杀死癌细胞。对电离辐射的抗性通常由DNA修复机制决定，DNA修复机制可以修复辐射引起的DNA损伤。辐射的最大毒性效应表现为双链DNA断裂的形成。这些断裂可以通过同源重组和非同源末端连接DNA修复机制来修复。由于辐射诱导的双链断裂的修复被阻断，因此抑制这些机制会导致辐射敏感性的增加。因此，了解双链断裂修复的分子机制对于设计新的放射增敏疗法是至关重要的。我们最近发现了一种以PARP14蛋白为核心的调节辐射抗性的新机制。PARP14是一种单-ADP-核糖基转移酶，与其同源酶PARP1不同，它不能催化多聚ADP-核糖链的形成，而只能将单分子ADP-核糖转移到底物上。单-ADP-核糖化是一种神秘的翻译后修饰，其在细胞中的功能尚不清楚。或初步结果显示，PARP14通过激活同源重组DNA修复促进双链断裂的修复。此外，我们的初步结果表明了这种激活的机制：PARP14单-ADP-核糖化重组因子RAD51，以促进RAD51从D-环中移除，从而允许D-环延伸超过断裂并完成重组反应。因此，我们的工作表明，PARP14抑制通过下调辐射诱导的双链DNA断裂的同源重组依赖的修复而导致辐射敏感性。在这个建议中，我们检验了PARP14通过RAD51单-ADP-核糖化通过同源重组促进辐射诱导的双链DNA断裂修复的假设。我们将采用一种全面、综合的方法来研究：1)PARP14通过同源重组和其他DNA修复机制在辐射诱导的DNA损伤修复中的作用；2)PARP14通过RAD51单-ADP核糖化在辐射诱导的双链断裂修复中的作用。我们的研究具有很高的创新性，因为它解决了一个新的，以前未知的单-ADP-核糖化在辐射抗性中的功能。我们的工作将揭示PARP14的单-ADP核糖化如何提高辐射抗性，并描述基于PARP14抑制的新的放射增敏方法。