猛龙的O-GlcNAcylation将葡萄糖信号转化为mTORC1的信号
Chenchen Xu1, Xiaoqing Pan2, Dong Wang1
1State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China.
Molecular cell
|August 4, 2023
概括
葡萄糖水平通过O-GlcNAcylation of Raptor控制细胞生长,这是一个关键的mTORC1蛋白. 这一过程通过促进mTORC1向 lysosome的移动来增强mTORC1的激活,而AMPK信号抑制mTORC1.
科学领域:
- 细胞代谢的细胞代谢.
- 分子信号通道的分子信号通道.
- 生物化学 生物化学
背景情况:
- 拉巴胺素复合体1 (mTORC1) 的机械标对于调节基于营养的可用性细胞生长和新陈代谢至关重要.
- 在mTORC1信号中断与各种疾病有关.
- 通过mTORC1有效感知葡萄糖对于细胞能量恒温至关重要.
研究的目的:
- 为了阐明葡萄糖诱导的mTORC1激活的调节机制.
- 为了研究O-GlcNAcylation of Raptor在mTORC1信号传递中的作用.
- 了解葡萄糖水平是如何传达给mTORC1.1.的.
主要方法:
- HEK293T细胞培养和操纵.
- 西方涂抹检测蛋白质的修饰 (O-GlcNAcylation,酸化).
- 免疫沉试验用于研究蛋白质与蛋白质相互作用 (Raptor-Rag GTPases).
- 同焦显微镜可视化mTOR转移到溶酶体.
主要成果:
- 在threonine 700中O-GlcNAcylation的Raptor对于葡萄糖诱导的mtORC1激活至关重要.
- 猛龙O-GlcNAcylation促进了猛龙和Rag GTPases之间的相互作用.
- 这种相互作用促进了mTOR在溶酶体表面的招募,激活mTORC1.1.
- 通过AMPK介导的Raptor酸化抑制了Raptor O-GlcNAcylation,并随后抑制了mTORC1的激活.
结论:
- 葡萄糖诱导的mTORC1激活是由O-GlcNAcylation精确控制的猛禽.
- 这种机制将细胞葡萄糖状态与mTORC1活性和溶酶体局部化联系起来.
- 猛禽O-GlcNAcylation和AMPK酸化之间的相互作用提供了一个复杂的调节网络,用于细胞的合成和代谢.
相关概念视频
PI3K/mTOR/AKT Signaling Pathway
3.7K
The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast, mTORC2 consists of a...
3.7K
mTOR Signaling and Cancer Progression
3.8K
The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...
The mTOR pathway or the...
3.8K
cAMP-dependent Protein Kinase Pathways
6.4K
Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...
6.4K
MAPK Signaling Cascades
5.7K
Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
5.7K
Insulin: The Receptor and Signaling Pathways
1.3K
Insulin action is mediated through a receptor tyrosine kinase, akin to the IGF-1 receptor. The number of receptors per cell varies significantly, from 40 on erythrocytes to 300,000 on adipocytes and hepatocytes. The insulin receptor consists of linked α/β subunit dimers, forming a heterotetramer glycoprotein with two extracellular α subunits and two β subunits spanning the membrane. The α subunits inhibit the inherent tyrosine kinase activity of the β subunits, but...
1.3K
GPCRs Regulate Adenylyl Cylase Activity
5.7K
Some GPCRs transmit signals through adenylyl cyclase (AC), a transmembrane enzyme. AC helps synthesize second messenger cyclic adenosine monophosphate (cAMP). AC catalyzes cyclization reaction and converts ATP to cAMP by releasing a pyrophosphate. The pyrophosphate is further hydrolyzed to phosphate by the enzyme pyrophosphatase, which drives cAMP synthesis to completion. However, cAMP is rapidly degraded to 5′ AMP by the enzymes phosphodiesterase (PDE), preventing overstimulation of...
5.7K


