通过SUMOylation在芽酵母中调节错误折叠的蛋白质聚合和降解
Austin Folger1, Emily Gutierrez-Morton1, Marie-Helene Kabbaj1
1Department of Biomedical Sciences, College of Medicine, Florida State University, 1115 West Call Street, Tallahassee, FL 32306-4300.
Molecular biology of the cell
|April 30, 2025
概括
SUMOylation,即小型泛胺类修饰剂 (SUMOs) 的附着,通过蛋白酶体促进错误折叠的亨廷丁蛋白 (Htt) 的降解. 这一过程有助于保持蛋白质的溶解性,并防止与神经退行性疾病相关的聚合.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 生物化学 生化学
背景情况:
- 蛋白质错误折叠和聚合是诸如亨廷顿病之类的神经退行性疾病的标志.
- 错误折叠的亨廷丁蛋白 (mHtt) 与扩展的多重胺 (polyQ) 重复容易聚合.
- SUMOylation (小型泛素类修饰剂结合) 是一种涉及蛋白质调节的翻译后修饰.
研究的目的:
- 研究SUMOylation在调节发芽酵母中错误折叠的亨廷丁蛋白 (Htt103QP-GFP) 的聚合和降解中的作用.
- 阐明SUMOylation影响生物分子凝聚物的形成和随后的蛋白质命运的机制.
主要方法:
- 在芽酵母中的Htt103QP-GFP的SUMOylation和polySUMOylation.
- FRAP (光漂白后光恢复) 试验.
- 用生物分子凝聚物破坏化学品进行处理.
- 蛋白质体降解和聚合物形成的分析 (SDS-不可溶性).
主要成果:
- 在芽酵母中证实了Htt103QP-GFP的SUMOylation.
- SUMOylation加速了Htt103QP-GFP的聚合和生物分子凝聚物的形成.
- 对polySUMO轴的干扰增加了Htt103QP-GFP的聚合.
- 损坏的SUMOylation延迟了蛋白质体的降解,增加了SDS不溶性聚合物,表明溶性降低.
结论:
- SUMOylation通过蛋白酶体促进了错误折叠的Htt103QP-GFP的降解.
- SUMOylation通过保持错误折叠的蛋白质的可溶性,促进了蛋白质体的降解.
- 这种机制可能对防止神经退行性疾病中有毒蛋白质聚合物的积累至关重要.
相关概念视频
Regulated Protein Degradation
7.1K
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
7.1K
Regulation of Expression at Multiple Steps
843
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the...
843
Overview of Secretory Vesicles
7.1K
Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
7.1K
Protein Folding Quality Check in the RER
3.6K
ER is the primary site for the maturation and folding of soluble and transmembrane secretory proteins. The calnexin cycle is a specific chaperone system that folds and assesses the confirmation of N-glycosylated proteins before they can exit the ER lumen. The primary players of this quality check pipeline are the lectins, ER-resident chaperones, and a glucosyl transferase enzyme. In case the calnexin system in the lumen fails to salvage a misfolded protein, it is transported to the cytoplasm...
3.6K
The Proteasome
776
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
776
Covalently Linked Protein Regulators
6.6K
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein....
These groups modify specific amino acids in a protein....
6.6K


