在S. cerevisiae U6 snRNP组装过程中,RNA修饰和Prp24协调Lsm2-8结合动态
Ye Liu1, Yuichiro Nomura1, Samuel E Butcher1
1Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA.
The Journal of biological chemistry
|April 11, 2025
概括
有效的结合体组合需要快速的U6小核RNA (snRNA) 与Lsm2-8复合体结合. 这项研究揭示了转录后RNA修饰和Prp24蛋白在动态上控制了用于拼接效率的这一关键步骤.
科学领域:
- 分子生物学分子生物学
- 处理和拼接RNA的处理和拼接.
- 生物化学 生物化学
背景情况:
- 结合体,一个由snRNP和蛋白质组成的复杂机器,在真核生物中从前mRNA中移除了内子.
- U6 snRNP组件对于拼接效率至关重要,但它的动力学知之甚少.
- U6 snRNP涉及U6 snRNA,Prp24和Lsm2-8异质合体,在酵母中有一个修饰的3'末端.
研究的目的:
- 在动力学上描述U6 snRNP的组装路径.
- 研究Prp24蛋白和转录后RNA修饰在U6 snRNA-Lsm2-8复合体形成中的作用.
- 了解控制高效U6 snRNP重组用于拼接的机制.
主要方法:
- 使用局部化单分子光谱学.
- 分析了U6 snRNA与Lsm2-8关联的动态途径.
- 评估了对Prp24和RNA修饰的依赖.
主要成果:
- 与U6 snRNA的Lsm2-8关联高度依赖于没有3'-end处理的Prp24.
- 经过处理的RNA很快就会招募Lsm2-8,即使没有Prp24.
- 转录后处理增强了Lsm2-8的关联性,而Prp24则促进了招募和保留.
结论:
- 有效的U6 snRNP组件依赖于动力选择机制.
- Lsm2-8优先结合3'-end修饰或Prp24结合的U6 snRNAs.
- 这种选择过程可能会防止Lsm2-8与非目标RNA的关联,确保拼接保真性.
相关概念视频
02:53Ribosomal RNA Synthesis
13.1K
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
13.1K
01:32RNA Splicing
56.2K
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...
56.2K
02:41Chromatin Structure Regulates pre-mRNA Processing
7.0K
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...
7.0K
01:34Directing Proteins to the Rough Endoplasmic Reticulum
7.2K
The organelle-specific signaling sequences direct proteins synthesized in the cytosol to their final destination like ER, mitochondria, peroxisomes, etc. Some of the proteins directed to ER are then trafficked via vesicles to other organelles within the cell or the extracellular environment through the Golgi complex. For example, the rough ER synthesizes soluble proteins for transportation to the lysosomes or secretion out of the cell. It can also synthesize transmembrane proteins that can...
7.2K
01:45Regulation of Nuclear Protein Sorting
2.4K
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
2.4K
01:57Protein Complexes with Interchangeable Parts
2.5K
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
2.5K