Elucidating roles of RTEL in replication fork repair in Drosophila melanogaster

阐明 RTEL 在果蝇复制叉修复中的作用

• 批准号: 8717809
• 负责人: Lydia Patrice Morris
• 金额: $ 5.15万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8717809
• 关键词: Animal Model; Animals; Apoptosis; Biological; Biological Assay; Biological Process; Cancer Etiology; Cell Cycle; Cell Cycle Arrest; Cell Cycle Checkpoint; Cell Cycle Progression; Cell Death; Cell Proliferation; Cell physiology; Cells; Cessation of life; DNA; DNA Damage; DNA Repair; DNA biosynthesis; Data; Defect; Development; Disease; Drosophila genus; Drosophila melanogaster; Dyskeratosis Congenita; Embryo; Event; Functional disorder; Genetic; Genetic Crossing Over; Genetic Recombination; Genome; Genomic Instability; Goals; Helicase Gene; Inherited; Lead; Loss of Heterozygosity; Maintenance; Malignant Neoplasms; Measures; Mind; Mitotic; Modeling; Molecular Genetics; Mus; Mutation; Pathology; Pathway interactions; Patients; Phenotype; Play; Predisposition; Premature aging syndrome; Proteins; Reaction; Recovery; Research; Research Personnel; Role; S Phase; Source; Structure; Telomere Length Maintenance; Telomere Maintenance; Testing; crosslink; cytotoxic; fly; helicase; homologous recombination; in vivo; insight; mouse model; mutant; novel; prevent; public health relevance; repaired; telomere; tool

DESCRIPTION (provided by applicant): The genomes of S-phase cells are especially vulnerable to DNA damage, and problems that arise during DNA replication are a significant source of genomic instability, an important hallmark of cancer. DNA helicases play an important role in counteracting these destabilizing events. This is emphasized by the fact that mutations in many of the helicase genes are associated with cancer predisposition and premature aging syndromes, and cells from these patients harbor a high level of genomic instability [1]. SNPs and mutations in the conserved DNA helicase gene RTEL have been associated with a variety of cancers and with forms of the telomere instability disorder dyskeratosis congenita [2-5] This proposal seeks to elucidate the DNA repair functions of the RTEL helicase with the ultimate goal of better understanding mechanisms of disease development in pathologies associated with genetic defects in RTEL and other DNA helicases. RTEL function has been explored through observations in patients' cells as well as studies in mouse and other animal models, which revealed roles in telomere length maintenance. In addition, previous studies have suggested roles for RTEL in counteracting mitotic crossovers, which can lead to loss of heterozygosity, through the homologous recombination pathway and in the repair of DNA crosslinks at replication forks. Despite these findings, the embryonic lethality of the mouse model and lack of in vivo DNA repair assays has limited the study of the DNA repair roles of RTEL. In addition to the many molecular genetic tools available, the fruit fly Drosophila melanogaster is an ideal animal model to study RTEL function due to the non-canonical structure of the fly telomeres, likely allowing for the examination of genome maintenance functions separately from the telomere- specific functions. The overall goal of this research is to elucidate RTEL biological function in DNA repair and understand how RTEL protects against the deleterious biological consequences of DNA damage including defective proliferation and death. To that end, the specific aims of this proposal are to (1) test models for RTEL function in homologous recombination, (2) test models for RTEL function in replication fork progression, and (3) determine the role of RTEL in promoting proper cellular proliferation, cell cycle progression, and viability.

描述（由申请人提供）：S期细胞的基因组特别容易受到DNA损伤，DNA复制过程中出现的问题是基因组不稳定的重要根源，而基因组不稳定是癌症的重要标志。 DNA 解旋酶在对抗这些不稳定事件中发挥着重要作用。许多解旋酶基因的突变与癌症易感性和早衰综合征相关，并且来自这些患者的细胞具有高度的基因组不稳定性，这一事实强调了这一点[1]。保守 DNA 解旋酶基因 RTEL 中的 SNP 和突变与多种癌症和端粒不稳定疾病先天性角化不良有关 [2-5] 该提案旨在阐明 RTEL 解旋酶的 DNA 修复功能，最终目标是更好地了解与 RTEL 和其他 DNA 解旋酶遗传缺陷相关的病理学疾病发展机制。通过对患者细胞的观察以及对小鼠和其他动物模型的研究，人们对 RTEL 功能进行了探索，揭示了其在端粒长度维持中的作用。此外，之前的研究表明 RTEL 在通过同源重组途径抵消有丝分裂交叉（可能导致杂合性丧失）以及复制叉处 DNA 交联修复中发挥作用。尽管有这些发现，小鼠模型的胚胎致死率和体内 DNA 修复检测的缺乏限制了 RTEL DNA 修复作用的研究。除了许多可用的分子遗传工具外，果蝇果蝇是研究 RTEL 功能的理想动物模型，因为果蝇端粒的非规范结构，可能允许将基因组维持功能与端粒特异性功能分开进行检查。这项研究的总体目标是阐明 RTEL 在 DNA 修复中的生物学功能，并了解 RTEL 如何防止 DNA 损伤的有害生物学后果，包括缺陷性增殖和死亡。为此，本提案的具体目标是（1）测试同源重组中 RTEL 功能的模型，（2）测试复制叉进展中 RTEL 功能的模型，以及（3）确定 RTEL 在促进适当细胞增殖、细胞周期进展和活力中的作用。