Molecular mechanisms of Werner syndrome helicase in genome stability and aging

项目总结 早衰症以加速的速度模仿衰老，是理解早产儿和早产儿的关键 和正常衰老。一类孕激素综合征是由DNA修复途径缺陷引起的。例如, 沃纳综合征(WS)是一种罕见的遗传性疾病，其特征是过早衰老和癌症，由 DNA修复解旋酶WRN的突变。WS患者紧密地概括了许多正常的衰老表型， 使WS成为老龄化的模式系统。然而，WS涉及的细胞和分子机制 人们对病理学仍知之甚少。在这里，我建议回答有关功能的关键问题 WRN通过包括结构生物学、单分子生物化学和细胞在内的跨学科方法 生物学。 我的职业目标是建立一个独立的研究项目，致力于了解 与衰老和衰老相关疾病相关的基因组不稳定的分子和细胞机制。AS 实现这一目标的第一步，我进行了单分子显微镜和 生物化学，补充了我在结构生物学和生物物理技术方面的背景。指导工作 K99/R00奖的阶段将为我提供冷冻电子显微镜、细胞生物学、 端粒生物学，以及通过一个由导师和顾问组成的专家组研究人类衰老的生物学。在这里，我 建议：(1)确定全长WRN的分子结构(2)确定核酸酶和 WRN的解旋酶活性被调节(3)确定WRN如何与端粒蛋白协同解旋 端粒复制过程中的G-四链以防止端粒丢失，以及(4)确定WRN缺乏 导致炎症和细胞过早衰老。这些目标的实现将是重要的一步。 我们对WRN在防止基因组不稳定中的作用的理解取得了进展，并将为我的 确定其他DNA修复酶和它们的基因组维持机制的长期目标 在人类衰老和与年龄相关的病理学中的重要性。 K99/R00奖将允许我建立一个独立的研究项目，这将使我成为一个强大的 美国一家领先研究机构终身教职的候选人。我的工作将提供重要的见解 WRN及其互动伙伴如何维护我们的基因组并帮助我们了解生物 WRN调控失调的后果。此外，这些研究将提供更详细的了解 WRN缺乏如何导致WS中发现的加速衰老表型。

PROJECT SUMMARY Progeroid syndromes mimic aging at an accelerated rate and are key to understanding both premature and normal aging. One class of progeroid syndromes results from defective DNA repair pathways. For example, Werner syndrome (WS)—a rare inherited disease characterized by premature aging and cancer—is caused by mutations in the DNA repair helicase WRN. WS patients closely recapitulate many normal aging phenotypes, making WS a model system for aging. However, the cellular and molecular mechanisms involved in WS pathologies remain poorly understood. Here, I propose to answer critical questions regarding the functions of WRN via an interdisciplinary approach that includes structural biology, single-molecule biochemistry, and cell biology. My career goal is to establish an independent research program dedicated to understanding the molecular and cellular mechanisms of genomic instability associated with aging and aging-related diseases. As a first step to achieving this goal, I have pursued postdoctoral training in single-molecule microscopy and biochemistry, complementing my background in structural biology and biophysical techniques. The mentoring phase of the K99/R00 award will provide me with additional training in cryo-electron microscopy, cell biology, telomere biology, and the biology of human aging through an expert group of mentors and advisors. Here I propose to: (1) Determine the molecular architecture of full-length WRN (2) Identify how the nuclease and helicase activities of WRN are regulated (3) Determine how WRN cooperates with telomeric proteins to unwind G-quadruplexes during telomere replication to prevent telomere loss, and (4) determine how WRN-deficiency leads to inflammation and premature cellular senescence. Completion of these aims will represent a major step forward in our understanding of WRN’s role in preventing genomic instability and will lay the groundwork for my long-term goals to determine the mechanisms of genome maintenance by other DNA repair enzymes and their importance in human aging and age-related pathologies. A K99/R00 award will allow me to establish an independent research program that will make me a strong candidate for a tenure-track position at a leading U.S. research institution. My work will provide important insights into how WRN and its interaction partners maintain our genomes and help us understand the biological consequences of WRN dysregulation. Furthermore, these studies will provide a more detailed understanding of how WRN-deficiency leads to accelerated aging phenotypes found in WS.