相关实验视频
Updated: Jul 29, 2026

11:09
An Easy Method for Plant Polysome Profiling
Published on: August 28, 2016
概括
耐干旱的在干燥过程中会失去多体体,然后才会增加核糖酶活性. 这种损失是由于核糖体流失和未能重新形成启动复合体,而不是RNA降解.
科学领域:
- 植物生理学 植物生理学
- 分子生物学分子生物学
- 干旱耐受性的机制
背景情况:
- 多聚体对蛋白质合成至关重要.
- 植物的干旱压力会导致显著的生理变化.
- 乡村虫 (Tortula ruralis) 是研究植物干燥耐受性的模型生物.
研究的目的:
- 调查干燥过程中Tortula ruralis多体损失的机制.
- 确定核糖核酶活性在多元体降解中的作用.
- 阐明核糖体功能在压力下的多元体维持中的参与.
主要方法:
- 在干燥和水合的Tortula ruralis.中量化多体水平.
- 在干燥过程中检测核糖酶活性.
- 对核糖体-信使RNA复合的分析.
主要成果:
- 在可观察到的核糖核酶活性增加之前,在干燥过程中,多胞体水平显著下降.
- 干燥中的核糖体没有发现与信使RNA片段复杂化.
- 证据表明,缺乏信使RNA的重新启动.
结论:
- 干燥过程中的多胞体损失是由核糖体流失的介导.
- 不能重新形成启动复合体有助于多元体损失.
- 这些机制在Tortula ruralis极端脱水期间保护转化机制.
相关概念视频
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Riboswitches
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The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
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mRNA Stability and Gene Expression
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Cis-acting Elements involved in mRNA stability
Cis-acting Elements involved in mRNA stability
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,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...

