在急性营养限制时的蛋白质合成依赖于蛋白质酶功能
Ramunas M Vabulas1, F Ulrich Hartl
1Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany. vabulas@biochem.mpg.de
概括
哺乳动物细胞使用蛋白质体蛋白质降解来维持急性氨基酸短缺期间的蛋白质合成. 当营养物质稀缺时,这种蛋白质酶功能对于细胞生存至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 营养物质感应的分子机制
- 蛋白质稳态是蛋白质的稳态.
背景情况:
- 细胞对营养缺乏的反应对生存至关重要.
- 蛋白酶体在氨基酸恒温中的作用尚未完全阐明.
- 自菌体-溶解体通路是已知的营养循环的机制.
研究的目的:
- 调查蛋白酶在急性氨基酸缺乏期间哺乳动物细胞存活中的作用.
- 了解在营养有限的条件下确保高效翻译的机制.
- 为了确定蛋白质体降解是否先于或补充其他营养感应途径.
主要方法:
- 使用的哺乳动物细胞培养,经过急性氨基酸剥夺.
- 采用蛋白酶体抑制作为一个关键的实验操纵.
- 监测蛋白质合成速率和氨基酸水平.
- 评估新生和现有的蛋白质的命运.
主要成果:
- 蛋白体蛋白质降解在营养稀缺期间为新的蛋白质合成提供了氨基酸.
- 新生和新合成的多被保护免受降解.
- 在营养缺乏期间抑制蛋白酶体导致了快速的氨基酸耗尽和翻译受损.
- 蛋白质酶的作用在自菌体-溶酶体通路激活之前就很明显了.
结论:
- 蛋白酶体在氨基酸供应急性中断后的细胞存活中发挥着关键作用.
- 蛋白质体降解是维持在急性营养应激下翻译效率的主要机制.
- 这项研究强调了蛋白酶体在细胞适应营养缺乏时的关键,以前被低估的作用.
相关概念视频
Proteins: Dietary Sources and Requirements
Consuming animal-based products offers high-quality proteins that contain optimal levels and combinations of essential amino acids, crucial for tissue repair and growth. Foods like eggs, milk, fish, and most meats are a source of complete proteins. Legumes and cereals are abundant in proteins; however, they typically lack a full range of essential amino acids. As a result, they are considered incomplete protein sources. Some plant sources like soybeans, quinoa, and amaranth do contain complete...
Overview of Protein Metabolism
Proteins are broken down into amino acids during digestion. Unlike fats and carbohydrates, which are stored for later use, proteins are not. Instead, amino acids are either used to produce ATP through oxidation or contribute to the creation of new proteins for the growth and repair of the body. Any surplus amino acids from the diet are converted into glucose or triglycerides rather than excreted.
Amino acids play various roles in the body once they are absorbed into cells. They are restructured...
Amino acids play various roles in the body once they are absorbed into cells. They are restructured...
Inborn Errors of Metabolism
Phenylketonuria (PKU) is a protein metabolism disorder characterized by high blood levels of the amino acid phenylalanine. This results from a mutation in the gene responsible for phenylalanine hydroxylase, an enzyme that converts phenylalanine into tyrosine. When this enzyme is deficient, phenylalanine builds up in the blood, leading to symptoms such as vomiting, rashes, seizures, growth deficiency, and severe mental retardation. An early diagnosis and a diet restricting phenylalanine intake...
Chronic Kidney Disease III: Interprofessional Care
Chronic kidney disease (CKD) requires collaborative and comprehensive management. CKD progresses through stages and can lead to end-stage kidney disease (ESKD) if untreated. Interprofessional collaboration and patient education are crucial, enabling patients to manage their health and improve their quality of life.Diagnostic approach for chronic kidney diseaseThe diagnosis of CKD primarily focuses on the glomerular filtration rate (GFR), which assesses kidney function by measuring how well...
Biosynthesis of Nucleic Acids
Nucleic acid biosynthesis is a fundamental biochemical process that produces the purine and pyrimidine nucleotides essential for DNA and RNA synthesis. This pathway maintains a balanced nucleotide pool, preventing imbalances that could jeopardize genetic integrity and cellular function. Given the crucial role of nucleotides, their synthesis is tightly regulated to ensure proper cellular homeostasis.Purine BiosynthesisThe biosynthesis of purine nucleotides begins with ribose-5-phosphate, a...
Stringent Response in E. coli
Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...


