减弱核糖体负载通过限制转化依赖的mRNA衰变来改善mRNA的蛋白质输出
Alicia A Bicknell1, David W Reid1, Marissa C Licata1
1Moderna, Inc, 325 Binney Street, Cambridge, MA 02142, USA.
Cell reports
|April 16, 2024
概括
优化信使RNA (mRNA) 治疗方法需要仔细设计编码序列 (CDS). 减弱,而不是最大化,核糖体负载可以提高mRNA稳定性和蛋白质输出,以获得更好的治疗疗效.
科学领域:
- 分子生物学分子生物学
- 生物技术是生物技术.
- 生物化学 生物化学
背景情况:
- 有效的信使RNA (mRNA) 疗法需要从每个mRNA分子中最大限度地生产蛋白质.
- 之前的研究表明,编码序列 (CDS) 设计显著影响蛋白质输出,优化子和更高的二次结构导致mRNA衰变速度更慢和表达率更高.
研究的目的:
- 研究CDS设计,翻译动力学和mRNA衰变率之间的关系.
- 阐明CDS在mRNA治疗中影响mRNA半衰期和蛋白质输出的机制.
主要方法:
- 对具有不同编码序列的mRNA变体的分析.
- 测量翻译启动和延长率.
- 对转化和死乙烯化依赖的mRNA衰变速率的评估.
- 从设计的mRNA结构中量化蛋白质输出.
主要成果:
- 由CDS影响的翻译启动和延长速率的差异直接影响翻译和死乙烯化依赖的mRNA衰变.
- 最稳定和表达最高的mRNA变体表现出中度的启动/延长率和核糖体负荷.
- 在高度稳定和表达性mRNA中观察到最小的翻译依赖mRNA衰变,这表明翻译动力学的平衡.
结论:
- 通过调节翻译动力学和随后的mRNA衰变路径,CDS设计极大地影响mRNA稳定性和蛋白质输出.
- 优化治疗mRNA疗效可能涉及减弱核糖体负载而不是仅仅最大化它,从而提高mRNA稳定性和蛋白质表达.
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