相关实验视频
Updated: Mar 13, 2026

10:49
Measuring RAN Peptide Toxicity in C. elegans
Published on: April 30, 2020
7.1K
C9orf72二重复物损害了没有膜的器官的组合,动力和功能
Kyung-Ha Lee1, Peipei Zhang1, Hong Joo Kim1
1Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
Cell
|October 22, 2016
概括
在ALS/FTD中,C9ORF72重复扩张会产生破坏细胞区的有毒蛋白质. 含有素的二重复蛋白与没有膜的细胞器相互作用并改变其功能.
科学领域:
- 神经科学
- 分子生物学
- 遗传学
背景情况:
- 肌缩侧面硬化 (ALS) 和前性痴呆 (FTD) 的最常见遗传原因是C9ORF72基因中的六核酸重复扩张 (GGGGCC或G4C2).
- 这种重复扩张通过非传统的翻译导致有毒二重复蛋白 (DPR) 的产生.
- 这些DPR蛋白与C9ORF72相关的ALS和FTD的发病有关.
研究的目的:
- 通过C9ORF72重复扩张生成的所有DPR的蛋白互动体.
- 研究这些相互作用的功能后果,特别是关于没有膜的器官.
- 阐明 DPR 导致神经退行的机制.
主要方法:
- 蛋白质组分析以识别DPR反应器.
- 生物化学测定用于研究蛋白质与蛋白质相互作用和相分离.
- 细胞和遗传模型 (Drosophila) 来评估已识别的相互作用和机制的体内相关性.
主要成果:
- 发现含有氨酸的DPRs,特别是polyGly-Arg (GR) 和polyPro-Arg (PR),与RNA结合蛋白和低复杂度序列域 (LCD) 的蛋白相互作用.
- 显著的GR/PR反应器是关键无膜有机体的组成部分,包括核细胞,核孔综合体和应力颗粒.
- 显示GR和PR蛋白质会改变含有LCD的蛋白质的相分离特性,破坏这些细胞区的动态和功能.
- 在Drosophila中进行的基因研究证实了这些相互作用在DPR中介毒性中的作用.
结论:
- DPRs,特别是GR和PR,与没有膜的细胞器的组成部分相互作用,破坏它们的正常功能.
- 在C9ORF72相关的ALS和FTD中观察到的神经毒性是由于DPRs破坏了无膜器官的动态.
- 针对这些相互作用或改变阶段分离可能为这些破坏性神经退行性疾病提供治疗策略.
相关概念视频
Amyloid Fibrils
12.5K
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
12.5K
Export of Misfolded Proteins out of the ER
5.4K
After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
5.4K
Protein Complex Assembly
17.0K
Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types. Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Many viruses self-assemble into a fully functional unit using the infected host cell to...
17.0K
The Unfolded Protein Response
6.7K
The ER is the hub of protein synthesis in a cell. It has robust systems to quality control protein folding and also for degradation of terminally misfolded proteins. Under normal conditions, a small proportion of misfolded proteins that cannot be salvaged need to be transported to the cytoplasm by the ER-associated degradation or ERAD pathways. However, if the ERAD cannot handle the misfolded proteins, the cell activates the unfolded protein response or UPR to adjust the protein folding...
6.7K
Porin Insertion in the Outer Mitochondrial Membrane
5.1K
Porins are beta-barrel proteins translocated to the mitochondrial outer membrane through the TOM complex into the intermembrane space. Porin precursors bind TIM chaperones within the intermembrane space and are guided to the Sorting and Assembly Machinery complex or SAM complex on the outer mitochondrial membrane.
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
5.1K
Translocation of Proteins into the Mitochondria
13.6K
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
13.6K

