核mRNP中mRNA出口者Mex67-Mtr2的水平升高会影响核mRNA出口
Nataliia Stefanyshena1, Katja Sträßer1,2
1Institute of Biochemistry, FB08, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
Nucleic acids research
|January 23, 2026
概括
核信使核核糖核蛋白颗粒 (mRNP) 中的Mex67过量阻碍了mRNA的输出. 通过过度表达适配器Nab2或Yara1来抑制出口缺陷,使Mex67水平正常化,揭示了精确的Mex67调节是有效基因表达的关键.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 核mRNA输出对于真核生物的基因表达至关重要.
- 墨西哥67-Mtr2复合体 (人类的NXF1-NXT1) 调解了这种出口.
- 像Hpr1,Nab2,Yara1和Npl3这样的适应蛋白参与其中,但它们的作用尚未完全理解.
研究的目的:
- 为了研究适配蛋白在mRNA出口中的作用.
- 确定核mRNP中Mex67水平对出口效率的影响.
- 阐明Hpr1功能与Mex67调节之间的关系.
主要方法:
- 在Saccharomyces cerevisiae中分析核信使核核糖核蛋白颗粒 (mRNP).
- 基因操纵包括基因删除 (Δhpr1) 和适应蛋白过度表达 (Nab2, Yra1).
- 在核mRNPs中量化Mex67水平.
主要成果:
- 缺乏Hpr1的细胞表现出核mRNA出口受损,核mRNP中Nab2,Yara1和Mex67的水平升高.
- 在Δhpr1细胞中过度表达Nab2或Yra1,挽救出口缺陷,并降低核mRNP中的Mex67水平.
- 核mRNP中Mex67的升高是出口缺陷的前身和可能原因,而不是相反.
结论:
- 在核mRNP中精确调节Mex67-Mtr2水平对于有效的核mRNA出口至关重要.
- Hpr1在调节Mex67水平方面发挥着至关重要的作用,间接影响出口.
- 在mRNP中异常的Mex67积累破坏了mRNA出口通路.
相关概念视频
02:31Nuclear Export of mRNA
8.7K
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
8.7K
02:31Nuclear Export of mRNA
5.3K
5.3K
01:42Nuclear Export
4.9K
The nucleus restricts several proteins within and allows others to pass. The restricted proteins possess a nuclear retention sequence or NRS, anchoring them to the nuclear lamins and preventing their transport to the cytosol. The non-restricted proteins, after their synthesis, are transported to their site of action, such as the cytosol or other organelles, with the help of nuclear export signals or NES.
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
4.9K
02:19Export of Mitochondrial and Chloroplast Genes
4.1K
A eukaryotic cell can have up to three different types of genetic systems: nuclear, mitochondrial, and chloroplast. During evolution, organelles have exported many genes to the nucleus; this transfer is still ongoing in some plant species. Approximately 18% of the Arabidopsis thaliana nuclear genome is thought to be derived from the chloroplast’s cyanobacterial ancestor, and around 75% of the yeast genome derived from the mitochondria’s bacterial ancestor. This export has occurred...
4.1K
02:22Regulated mRNA Transport
7.0K
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing...
7.0K
02:27Nonsense-mediated mRNA Decay
11.7K
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,...
11.7K