在ER出口站点的TDP43聚合损害了ER到Golgi的运输
Hongyi Wu1, Loo Chien Wang2, Belle M Sow1
1Mechanobiology Institute, National University of Singapore (NUS), Singapore, Singapore.
Nature communications
|October 18, 2024
概括
人体细胞中的蛋白质聚合形成了多样化的包容. 一种关键的蛋白质,TDP43,聚合在肌缩侧面硬化症 (ALS) 的ER出口部位,破坏细胞运输.
科学领域:
- 细胞生物学 细胞生物学
- 神经科学是一个神经科学.
- 蛋白质生物化学 蛋白质生物化学
背景情况:
- 蛋白质聚合是与年龄有关的疾病的核心.
- 蛋白质聚合物形成的机制及其对细胞的影响尚未完全理解.
- 在蛋白质毒性压力下确定形成聚合物的蛋白质至关重要.
研究的目的:
- 在蛋白质毒性压力下识别人类细胞中形成聚合物的蛋白质.
- 为了表征形成的不同类型的蛋白质含体.
- 研究TDP43聚合在肌缩侧面硬化症 (ALS) 中的作用.
主要方法:
- 利用基于突变Hsp104的报道系统来检测蛋白质聚合物.
- 在受到蛋白质毒性压力的人类细胞中分析了蛋白质聚合.
- 研究了TDP43在不同类型的聚合物中的定位和动态.
- 研究了TDP43聚合对ER到Golgi运输的影响.
主要成果:
- 确定了300多种蛋白质,形成了独特的聚合物包含.
- 在ER退出站点 (ERES) 上,TDP43在应力颗粒和新型非动态内含物之间进行动态分区.
- TDP43-ERES联合聚合是由各种蛋白质毒性压力诱导的,并在ALS患者的运动神经元中观察到.
- 在ERES的TDP43聚合导致货物滞留,延迟了ER到Golgi的运输.
结论:
- 蛋白质毒性压力会诱导各种蛋白质聚合途径.
- 在ERES的TDP43聚合代表了ALS的新型致病机制.
- 由于TDP43聚合,ER-to-Golgi运输的中断有助于ALS的细胞功能障碍.
相关概念视频
Export of Misfolded Proteins out of the ER
3.5K
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...
3.5K
Post-translational Translocation of Proteins to the RER
5.6K
A sizable fraction of proteins destined for ER are first synthesized in the cell cytosol and then transported across the ER membrane–a process called post-translational translocation. Similar to cotranslationally translocated proteins, these proteins also use the Sec translocon complex to enter the ER lumen.
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
5.6K
Vesicular Tubular Clusters
2.4K
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
With the help of motor proteins such...
2.4K
Tail-anchoring of Proteins in the ER Membrane
3.1K
Tail-anchored, or TA, proteins are estimated to make up to 3-5% of membrane proteins found in the eukaryotic cell. Such proteins have a single transmembrane domain located approximately 30 amino acid residues upstream from the C-terminal end. As a result, the signal recognition particle (SRP) cannot guide a TA protein to the ER membrane for cotranslational insertion. Hence, they are integrated into the ER membrane post-translationally using their C-terminal end as the anchor. TA proteins...
3.1K
ER Retrieval Pathway
3.8K
In the secretory pathway, vesicles transport proteins from one cellular compartment to another in forward transport to deliver the protein to its correct location. Occasionally, misfolded proteins and incorrect proteins escape their original compartments, and a retrieval pathway is used to return the escaped proteins to their original compartment.
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
3.8K
Directing Proteins to the Rough Endoplasmic Reticulum
7.1K
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...
7.1K


