在压抑的复合体中,LARP1结合了核糖体和TOP mRNA
James A Saba1,2, Zixuan Huang3, Kate L Schole1,2
1Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
The EMBO journal
|November 12, 2024
概括
LARP1直接与核糖体子单元结合,而不是转化核糖体,以调节核糖体蛋白mRNA (TOP). 这挑战了LARP1介导的TOP镇压和稳定现有模式.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 细胞生物学 细胞生物学
背景情况:
- 末端寡胺基基基因含有mRNAs (TOPs) 编码核糖体蛋白质,对于调节核糖体合成至关重要.
- 通过与40S-或80S-核糖体复合体的相互作用,LARP1已涉及抑制和稳定TOP,但分子机制尚不清楚.
研究的目的:
- 阐明LARP1与核糖体子单元和TOP mRNA相互作用的分子机制.
- 研究LARP1-核糖体复合体在TOP mRNA调节中的作用.
主要方法:
- 电子显微镜 (Cryo-EM) 用于确定LARP1-核糖体复合体的结构.
- 生物化学试验研究LARP1与核糖体子单元和TOP的结合.
主要成果:
- LARP1通过一个新的域直接与非翻译的40S核糖体子单元结合,遮住mRNA通道.
- 在压力期间增加自由核糖体子单元的可用性时,LARP1形成80S复合体与TOP.
- 对于LARP1在TOP抑制和稳定方面的已知功能,核糖体结合并非必不可少.
结论:
- LARP1直接与核糖体子单元结合,为其调节作用提供了新的视角.
- 通过压抑的40S/80S-TOP复合体进行LARP1-介导的TOP调节的现有模型需要修订.
- 这项研究为LARP1-核糖体相互作用和TOP mRNA调节提供了关键的分子见解.
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