相关实验视频
Updated: Jun 8, 2026

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A Reporter Based Cellular Assay for Monitoring Splicing Efficiency
Published on: September 15, 2021
U1 snRNP保护了前mRNAs免受过早的裂变和多基化
Daisuke Kaida1, Michael G Berg, Ihab Younis
1Howard Hughes Medical Institute, Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6148, USA.
Nature
|October 1, 2010
概括
U1小核核核糖核蛋白 (snRNP) 的倒退抑制了拼接,并导致过早的多核化. 这揭示了U1 snRNP在保护转录组免受神秘的多化信号方面发挥着关键的,独立于拼接的作用.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 基因表达规范 基因表达规范
背景情况:
- 在真核生物中,U1小核核核糖核蛋白 (snRNP) 对于结合体组合至关重要.
- 与其他snRNP相比,人类细胞表现出较高的U1 snRNP丰度.
- 目前尚不完全了解U1 snRNP过剩的确切功能.
研究的目的:
- 为了研究U1 snRNP的功能,超出其在拼接中的正规作用.
- 了解人类细胞中U1 snRNP丰富的原因.
- 确定U1 snRNP的潜在的独立于拼接的作用.
主要方法:
- 在HeLa细胞中使用反感性Morpholino oligonucleotides对U1 snRNP的功能性淘汰.
- 基因组片微阵列用于识别累积的未拼接的前mRNAs.
- 将U1 snRNP的淘汰效应与U2 snRNP抑制的比较.
主要成果:
- U1 snRNP的敲除抑制了mRNA前拼接,并导致了内部的密码多基解信号的过早裂变和多基解.
- 过早的多基化依赖于U1 snRNP,仅仅在U2 snRNP抑制下没有观察到.
- U1 snRNA-pre-mRNA基配对对于抑制过早的裂变和多基化至关重要.
结论:
- 在保护转录组方面,U1 snRNP具有关键的独立于拼接的功能.
- 这一功能涉及到在隐形位置防止过早的多化.
- 这些发现表明,U1 snRNP的过剩可能与这种保护作用有关.
相关概念视频
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
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,...
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,...
Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
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...

