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在C9ORF72ALS/FTD中通过独特和冗余的AUG启动密码子翻译二重复蛋白
Yoshifumi Sonobe1,2,3, Soojin Lee4,5, Gopinath Krishnan4,5
1University of Chicago Medical Center, Chicago, United States.
eLife
|September 7, 2023
概括
科学家们发现,ALS和FTD中的有毒二重复蛋白是使用标准启动信号制造的,这与之前的想法不同. 这一发现为C9orf72相关的神经退行性疾病提供了新的见解.
科学领域:
- 神经遗传学 神经遗传学
- 分子生物学分子生物学
- 神经退行性疾病 神经退行性疾病
背景情况:
- C9orf72 六核酸重复扩张是肌缩侧面硬化症 (ALS) 和前性痴呆症 (FTD) 的主要遗传原因.
- 这些疾病的病理包括从扩展重复的感觉和反感觉转录中翻译的二重复 (DPR) 蛋白质.
- 众所周知,感觉 DPR 通过非正典启动进行翻译,但反感觉 DPR 合成的机制仍然不清楚.
研究的目的:
- 研究由C9orf72重复扩张产生的反意义二重复 (DPR) 蛋白质,特别是聚PR和聚PG的翻译机制.
- 确定正规 (AUG) 和非正规启动密码子在反意义DPR合成中的作用.
- 探索翻译启动因素的参与,如EIF2D,在反意义DPR制作中.
主要方法:
- 利用遗传结构来研究来自C9orf72位点的反意义转录的翻译.
- 采用位点定向突变发生法来识别聚PR和聚PG合成所需的关键AUG编码.
- 评估了对抗意义DPR翻译的真核转化启动因子2D (EIF2D) 的要求.
主要成果:
- 提供了对反意义DPR,聚PR和聚PG的规范AUG-依赖翻译的证据.
- 证明单个AUG编码子对于聚PR合成至关重要,而聚PG合成则涉及三个AUG编码子之间的冗余性.
- 表明EIF2D不需要用于AUG依赖的多PR和多PG的翻译,这表明对感觉和反感觉DPR的启动机制是不同的.
结论:
- 在C9orf72-关联的ALS和FTD中,反意义双重复蛋白通过正规的AUG启动翻译来合成.
- 显而易见的翻译启动路径可能控制来自C9orf72位点的感觉和反感觉DPR的合成.
- 这些发现可能对理解其他核酸重复扩张障碍有更广泛的意义.
关键词:
在AUG启动密码子.C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C9ORF72C骨髓缩侧面硬化症 (ALS) 是一种双蛋白重复的蛋白质重复前性痴呆症前性痴呆症遗传学 遗传学 遗传学 是一个基因组学就是基因组学.人类 人类 人类 人类 人类 人类 人类由iPSC衍生的神经元.这里是鼠标鼠标鼠标鼠标鼠标鼠标.神经科学 神经科学相关概念视频
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