在更活跃的多元体中,在翻译上较不活跃的mRNA中,miRNA向的mRNA的丰富
Tingzeng Wang1, Shuangmei Tian1, Elena B Tikhonova2
1Department of Environmental Toxicology, and The Institute of Environmental and Human Health (TIEHH), Texas Tech University, Lubbock, TX 79416, USA.
Biology
|December 22, 2023
概括
微RNAs (miRNAs) 针对mRNA进行翻译抑制和降解. 这项研究揭示了miRNA向的mRNA在光聚体中表现出丰富性,使它们与翻译和抑制的关联相协调.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 转录后条例 转录后条例 转录后条例
背景情况:
- 微RNAs (miRNAs) 是基因表达的关键调节者,主要通过抑制翻译和促进mRNA降解,通过3'-不翻译区域 (UTR) 的结合位进行作用.
- 尽管它们具有抑制作用,但矛盾的是,miRNA点与多胞体有关,多胞体是活跃翻译的细胞机械.
研究的目的:
- 调查miRNA目标的多体关联,并调和它们与翻译机械相关的明显悖论.
- 阐明开放式读取 (ORF) 长度和miRNA结合部位在调节mRNA多体组分布中的作用.
主要方法:
- 野生类型 (WT) 人类细胞和因DICER1基因中断而缺乏成熟miRNA生产的同位素突变 (MT) 细胞的轻重多体形比较.
- 在ORF长度和3'-UTRmiRNA结合位数的关系下,分析了跨多体组的mRNA丰度比率.
主要成果:
- miRNA活动减少了ORF长度对轻重多体之间的mRNA丰度比率的影响.
- 针对miRNA的mRNA在WT细胞中表现出光聚体的丰富 (光聚体丰富),在缺乏DICER1的MT细胞中被废除.
- 在MT细胞中,光聚体丰富减少的程度与3'-UTR小RNA结合点的数量密切相关,转录因子和蛋白激酶是高度丰富的mRNA群.
结论:
- 这些发现支持miRNA向mRNA的光多体丰富模型,解释了它们与翻译抑制的多体关联.
- 开放式读取 (ORF) 长度被确定为一个重要的,但被低估的,miRNAs在转录组调节中的调节参数.
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