在人类重复扩张疾病中脱离转录凝聚物
Shaon Basu1, Sebastian D Mackowiak1, Henri Niskanen1
1Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany.
Cell
|May 11, 2020
概括
转录因子 (TF) 的氨基酸重复扩张导致遗传性疾病. 改变这些TF的相位分离会破坏细胞功能,这可能解释疾病机制.
科学领域:
- 分子生物学
- 遗传学
- 生物化学
背景情况:
- 转录因子 (TF) 的内在失序区域 (IDR) 的氨基酸重复扩张与20多种人类遗传性疾病有关.
- 在这些疾病中蛋白质聚合的作用是有争议的,需要进一步研究分子机制.
- 由HOXD13TF中的氨酸重复扩张引起的遗传性综合性.
研究的目的:
- 调查HOXD13中的氨酸重复扩张如何影响其与转录共激活剂的相分离和共凝结.
- 探索HOXD13重复扩展对凝结物组成和转录程序的体外和体内后果.
- 确定与其他疾病相关的TF重复扩张是否发生类似的相隔变化.
主要方法:
- 在体外分离测试以评估野生类型和扩展HOXD13的行为.
- 在小鼠共聚性样本中进行细胞研究,以分析HOXD13凝结物的组成和转录的变化.
- 对其他与疾病相关的TF (HOXA13,RUNX2,TBP) 具有重复扩张的相分离特性进行比较分析.
主要成果:
- 在HOXD13中,氨酸重复扩张显著改变了其相分离能力和与转录辅助激活剂共同凝结的能力.
- 在体外和体内,HOXD13重复扩张会扰乱含有HOXD13的凝结物的组成.
- 其他TF (HOXA13,RUNX2,TBP) 的疾病相关的重复扩张也改变了它们的相分离特性.
- 由于HOXD13的重复扩张,转录程序以细胞特异的方式发生改变.
结论:
- 由于改变TF相分离,转录凝聚物的不混合或破坏可能是与重复扩张相关的人类病理的基础.
- 这些发现为了解由TF重复扩张引起的转录失调相关的疾病提供了分子框架.
- 建议对TF IDR进行分子分类,以帮助剖析疾病中的TF功能.
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