人类活性端粒酶与端粒保护蛋白TPP1的结构
Baocheng Liu1, Yao He1,2, Yaqiang Wang1
1Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
Nature
|April 14, 2022
概括
人类端粒酶 (TERT) 和端粒酶RNA (TER) 结构揭示了特林蛋白TPP1如何招募和激活端粒酶. 这些发现揭示了端粒酶功能和潜在的药物点.
科学领域:
- 生物化学
- 分子生物学
- 结构生物学
背景情况:
- 人类端粒酶是一种维护染色体末端 (端粒) 的必不可少的核糖蛋白复合体.
- 端粒酶活性对于细胞衰老,干细胞更新和癌症进展至关重要.
- 庇护蛋白TPP1在端粒的端粒酶招募和激活中发挥着关键作用.
研究的目的:
- 确定人体端粒酶催化核 (TERT和TER) 的冷电子显微镜结构及其与TPP1的复合物.
- 阐明 TPP1 招募和激活端粒酶的分子机制.
- 确定与端粒酶相关的疾病的潜在药物点.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来获得高分辨率的结构.
- 结构分析的重点是TERT,TER和TPP1之间的相互作用.
- 进行了与Tetrahymena telomerase进行的比较结构分析.
主要成果:
- 确定了人类端粒酶催化核 (TERT和TER) 的结构.
- 与TPP1复合的端粒酶结构揭示了涉及TERT的TEN和TRAP领域的结构接口.
- 证明TPP1结合会抑制TEN-TRAP的结构动态,定义招募和激活要求.
- 在人类和四胺端粒酶之间保留了DNA处理的结构元素.
- 结合端粒酶抑制剂BIBR1532的结合部位在TER伪结和TERT指的相互作用中被确定.
- 关键接口 (TERT-TER,TEN-TRAP-TPP1) 在端粒病变中涉及.
结论:
- TPP1-TERT接口对于端粒酶的招募和激活至关重要.
- 结构洞察力提供了对端粒酶功能的机理理解.
- 已识别的接口和抑制剂结合部位代表了端粒病和癌症的潜在治疗点.
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