Structural Biology of Tetrahymena Telomerase Interactions at Telomeres

四膜虫端粒酶在端粒相互作用的结构生物学

• 批准号: 2016540
• 负责人: Juli Feigon
• 金额: $ 87万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2016540&HistoricalAwards=false
• 关键词: Structural; Biology; Tetrahymena; Telomerase; Interactions

Telomerase is a special enzyme composed of proteins and RNA that maintains the DNA at the very ends of our chromosomes, called telomeres. Telomerase is a highly regulated determinant of stem cell renewal, aging, and tumorigenesis. In this research project, the PI will investigate the structure and function of proteins that interact with telomerase and telomeres. The project will use telomerase and telomere binding proteins from the model organism Tetrahymena, a ciliated protozoan, which has previously led to basic discoveries. This project will provide essential training for graduate students and postdoctoral fellows in structural biology and biophysics and help them become the next generation of leaders in this multidisciplinary field. This project will also train women, minority, and economically disadvantaged high school, undergraduate, and graduate students to pursue careers in science. Telomerase is an RNA-protein complex (RNP) that extends the 3’ ends of linear chromosomes by repetitively synthesizing the short telomere repeat sequence (TTGGGG in ciliates) using an RNA template embedded in its telomerase RNA (TER) and its specialized telomerase reverse transcriptase (TERT). Telomerase activity at telomeres counteracts the loss of DNA that would otherwise occur during each round of replication. Telomerase is recruited to telomeres and activated by telomere end protection proteins, which otherwise serve to protect telomere ends from being detected as double strand breaks by the DNA damage response. This project will use NMR spectroscopy, X-ray crystallography, cryo electron microscopy (cryoEM), and biochemical methods to investigate the structures and interactions of Tetrahymena telomerase 741 and TEB with p50 and with telomere end-protection proteins, to elucidate their roles in telomeric DNA synthesis, regulation, and end protection. This project is supported by the Molecular Biophysics Cluster of the Molecular and Cellular Biosciences Division in the Directorate for Biological Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

端粒酶是一种由蛋白质和RNA组成的特殊酶，它将DNA保持在我们染色体的末端，称为端粒。端粒酶是干细胞更新、衰老和肿瘤发生的高度调节的决定因素。在这个研究项目中，PI将研究与端粒酶和端粒相互作用的蛋白质的结构和功能。该项目将使用来自模式生物四膜虫（一种纤毛虫原生动物）的端粒和端粒结合蛋白，该生物此前曾获得过基本发现。该项目将为结构生物学和生物物理学的研究生和博士后研究员提供必要的培训，并帮助他们成为这一多学科领域的下一代领导者。该项目还将培训妇女、少数民族和经济困难的高中生、本科生和研究生从事科学事业。端粒酶是一种RNA-蛋白质复合物（RNP），其通过使用嵌入其端粒酶RNA（TER）中的RNA模板和其专门的端粒酶逆转录酶（TERT）重复合成短端粒重复序列（纤毛虫中为TTGGGG）来延伸线性染色体的3'端。端粒上的端粒酶活性抵消了在每一轮复制过程中可能发生的DNA丢失。端粒酶被募集到端粒并被端粒末端保护蛋白激活，端粒末端保护蛋白另外用于保护端粒末端免于被DNA损伤反应检测为双链断裂。本项目将利用核磁共振波谱、X射线晶体学、冷冻电子显微镜（cryoEM）和生物化学方法研究四膜虫端粒酶741和TEB与p50和端粒末端保护蛋白的结构和相互作用，以阐明它们在端粒DNA合成、调节和末端保护中的作用。 该项目由生物科学理事会分子和细胞生物科学部的分子生物物理学小组支持。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Structures of telomerase at several steps of telomere repeat synthesis.

• DOI: 10.1038/s41586-021-03529-9
• 发表时间: 2021-05
• 期刊: Nature
• 影响因子: 64.8
• 作者: He Y;Wang Y;Liu B;Helmling C;Sušac L;Cheng R;Zhou ZH;Feigon J
• 通讯作者: Feigon J

Structure of Tetrahymena telomerase-bound CST with polymerase α-primase.

• DOI: 10.1038/s41586-022-04931-7
• 发表时间: 2022-08
• 期刊: Nature
• 影响因子: 64.8

A structurally conserved human and Tetrahymena telomerase catalytic core

• DOI: 10.1073/pnas.2011684117
• 发表时间: 2020-11
• 期刊: Proceedings of the National Academy of Sciences
• 作者: Yaqiang Wang;M. Gallagher-Jones;L. Sušac;He Song;J. Feigon

Structure of S. pombe telomerase protein Pof8 C-terminal domain is an xRRM conserved among LARP7 proteins

• DOI: 10.1080/15476286.2020.1836891
• 发表时间: 2020-11-01
• 期刊: RNA BIOLOGY
• 影响因子: 4.1
• 作者: Basu, Ritwika;Eichhorn, Catherine D.;Feigon, Juli
• 通讯作者: Feigon, Juli