一个特异于试管体的复合体调解了细胞质LSUrRNA的后期处理
Simona Amodeo1, Mauro Fischli1, Silke Oeljeklaus2
1Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland.
Nucleic acids research
|December 14, 2025
概括
研究人员发现了TbLrRP1和TbLrRP2,这两种蛋白质对于特异于类细胞体的大亚单元 (LSU) 的RNA处理至关重要. 这些蛋白质形成一个复合体,当耗尽时,会破坏LSU RNA成熟,并影响试管体生长.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 寄生虫学的寄生虫学
背景情况:
- 大多数真核生物与Trypanosoma brucei不同地处理细胞质大亚单元 (LSU) RNA.
- T. brucei 独特地将其细胞质 LSU RNA 处理成六个不同的碎片.
- 驱动这种试酶特异性RNA处理途径的特定因素以前未被确定.
研究的目的:
- 确定和描述Trypanosoma brucei独特的细胞质LSU RNA处理的重要组成部分.
- 阐明这些新发现的处理因子的功能和本地化.
主要方法:
- 蛋白质的识别和表征.
- 基因沉默 (耗尽) 实验以评估蛋白质功能.
- 使用显微镜进行亚细胞局部化研究.
- 分析RNA加工中间体和多体体的结合.
主要成果:
- 鉴定出TbLrRP1和TbLrRP2是三组特异性LSU RNA处理途径的重要组成部分.
- 这些蛋白质形成了一个局部化在ER膜和核外的异构体复合体.
- 耗尽TbLrRP1或TbLrRP2会破坏LSURNA处理,导致多体体中未经处理的中间体和受损的试体生长.
- TbLrRP2的与核酶相关的域 (NERD) 作为核糖核酶起作用,而TbLrRP1的DEDDh域似乎具有支架作用.
结论:
- 一种新的,谱系特异性的蛋白质复合体 (TbLrRP1-TbLrRP2) 在Trypanosoma brucei中调解了晚期细胞质LSU RNA成熟.
- 这种复杂的突出突出了试体细胞核核核糖体生物发生的独特适应.
- TbLrRP2的NERD域代表了参与这种特定RNA处理途径的核糖酶.
相关概念视频
Protein Translocation Machinery on the ER Membrane
6.4K
The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the...
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the...
6.4K
LTR Retrotransposons
19.4K
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
19.4K
Directing Proteins to the Rough Endoplasmic Reticulum
16.6K
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...
16.6K
Regulation of Nuclear Protein Sorting
3.2K
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...
3.2K
RNA Splicing
60.2K
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...
60.2K
Cotranslational Protein Translocation
9.5K
Translocation of proteins across membranes is an ancient process that occurs even in bacteria and archaebacteria. In fact, the components of the translocation machinery are still conserved between prokaryotes and eukaryotes.
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
9.5K


