相关实验视频
Updated: Jul 20, 2026

14:40
Expression Analysis of Mammalian Linker-histone Subtypes
Published on: March 19, 2012
概括
鼠标L细胞异质核RNA (hnRNA) 有四种5'终端类型. 纯氨酸核酸启动hRNA转录,而pyrimidine终结的hRNA可能是内部裂变事件的结果.
科学领域:
- 分子生物学分子生物学
- RNA 生物化学 生物化学
- 基因表达 基因表达
背景情况:
- 异质核RNA (hnRNA) 在基因表达中起着至关重要的作用.
- 了解hnRNA的5'端结构是破译转录启动和处理的关键.
- 盖帽结构是mRNA稳定性和翻译的重要修改.
研究的目的:
- 为了分析小鼠L细胞的酸化和封闭5'末端的hNRNA.
- 为了阐明不同hRNA的核酸组成.
- 为 hnRNA 和 mRNA 前体关系提出一个模型.
主要方法:
- 分析hNRNA的酸化和封闭的5'末端.
- 核酸结构的鉴定 (pppXp,ppXp,pXp,m7/GpppXmp).
- 在不同终点的核酸物种的量化.
主要成果:
- 在小鼠L细胞hRNA中发现了四种类型的5'终端.
- 转录启动仅涉及纯氨酸核酸 (GTP,ATP).转录启动仅涉及纯氨酸核酸 (GTP,ATP).转录启动仅涉及纯氨酸核酸 (GTP,ATP).转录启动仅涉及纯氨酸核酸 (GTP,ATP).转录启动仅涉及纯氨酸核酸 (GTP,ATP).转录启动仅涉及纯氨酸核酸 (GTP,ATP).转录启动仅涉及纯氨酸核酸 (GTP,ATP).
- 含有皮里米丁的5'终端可能来自较大的转录的内部裂变.
结论:
- hnRNA启动仅发生在纯氨酸核酸中.
- 胺终结的hNRNA表明主要转录的内部裂变.
- 提出了一个模型,其中mRNA序列可以来自hNRNA前体的5'末端和内部分裂部位.
相关概念视频
pre-mRNA Processing
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Eukaryotic RNA Polymerases
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All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
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The chromatin structure, especially...
The chromatin structure, especially...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
mRNA Stability and Gene Expression
The structure and stability of mRNA molecules regulates gene expression, as mRNAs are a key step in the pathway from gene to protein. In eukaryotes, the half-life of mRNA varies from a few minutes up to several days. mRNA stability is essential in growth and development. The absence of the proteins regulating its stability, such as tristetraprolin in mice, can cause systemic issues, including bone marrow overgrowth, inflammation, and autoimmunity.
Cis-acting Elements involved in mRNA stability
Cis-acting Elements involved in mRNA stability
Pre-mRNA Processing: Modification of pre-mRNA Ends
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps the cell...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps the cell...

