核糖体通过一般化移和外mRNA衰变来调节转录组的丰富性
Yujie Zhang1, Lilit Nersisyan2, Eliska Fürst3
1SciLifeLab, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna 171 65, Sweden.
Molecular cell
|May 16, 2025
概括
在营养不良的情况下,酵母细胞使用 -1 核糖体框架转移来触发mRNA衰变,减少蛋白质合成和生长. 这种保存机制将蛋白质需求与mRNA控制联系起来.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
背景情况:
- 细胞适应环境变化依赖于转录组调节.
- 通过合成和衰变速度来控制mRNA的丰度.
- 营养状况显著影响细胞过程.
研究的目的:
- 为了研究酵母细胞如何在营养不良的情况下适应其转录组.
- 为了阐明控制mRNA衰变的机制,以应对营养限制.
- 确定诱导mRNA衰变的因素,并评估这一过程的保存.
主要方法:
- 用RNA代谢标记来量化mRNA衰变速率.
- 对核糖体框架转移事件的分析 (-1 框架转移).
- 对无意义介导的mRNA衰变 (NMD) 途径参与的调查.
- 在mRNA衰变诱导中对子最佳性的作用的评估.
主要成果:
- 营养不良会导致S. cerevisiae转录基因组中的 - 1 核糖体框架转移.
- 在营养应激下,加速的,外框的,协同翻译的mRNA衰变发生.
- 无意中介的mRNA衰变 (NMD) 在恶劣条件下占总mRNA衰变的至少三分之一.
- 低密码子最佳性被确定为触发这种mRNA衰变机制的关键因素.
- 观察到的现象在细菌和人类中都存在.
结论:
- 直接反机制将蛋白质需求与mRNA丰度控制相结合,以限制细胞生长.
- 核糖体框架转移和随后的mRNA衰变是对营养稀缺的调节反应.
- 这项研究扩大了对mRNA质量控制在细胞调节中的功能作用的理解.
相关概念视频
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Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
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