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核糖体质量控制因子抑制来自GC丰富重复的重复关联非AUG转化
Yi-Ju Tseng1,2, Amy Krans1,3, Indranil Malik1,4
1Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA.
Nucleic acids research
|February 27, 2024
概括
核糖体质量控制因素限制了重复扩张障碍的有毒蛋白质生产,如ALS和FTD. 增强这些因素可能为这些神经退行性疾病提供治疗策略.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 在C9ORF72和FMR1中富含GC的重复扩张会导致神经退行性疾病,包括肌缩性侧面硬化/前性痴呆症 (C9ALS/FTD) 和脆弱X关联震/缺氧综合征 (FXTAS).
- 这些重复形成RNA结构,驱动重复关联的非AUG (RAN) 翻译,产生涉及疾病发病的有毒蛋白质.
研究的目的:
- 调查富含GC的重复是否会触发核糖体停滞并阻碍转化延长.
- 确定与核糖体相关的质量控制 (RQC) 因素在调节RAN转化中的作用.
主要方法:
- 使用记者测试来评估RAN翻译产品的积累.
- 通过枯竭和过度表达操纵RQC因子 (NEMF,LTN1,ANKZF1) 的表达.
- 分析了来自C9ALS/FTD患者的患者诱导多能干细胞 (iPSC) 神经元.
主要成果:
- RQC因子的耗尽显著增加了来自G4C2和CGG重复的RAN转换产品.
- 过度表达RQC因子降低了RAN产量在记者试验和iPSC衍生的神经元.
- 检测到部分合成的重复产物,随着RQC因子耗尽而增加,表明核糖体停滞.
- 影响RQC因子的影响是RNA序列,而不是氨基酸含量,突出了RNA二次结构的作用.
结论:
- 在RAN转化过程中,核糖体停滞和RQC通路激活作为产生有毒RAN产物的自然制动.
- 增加RQC活动为富含GC的重复膨胀障碍提供了潜在的治疗途径.
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