卡尔雷蒂库林对于整合素介导的信号和细胞粘附至关重要
M G Coppolino1, M J Woodside, N Demaurex
1Division of Cancer Research, Sunnybrook Health Science Centre, Toronto, Ontario, Canada.
Nature
|April 24, 1997
概括
卡尔雷蒂库林对于因特林介导的细胞粘附和信号传递至关重要. 卡尔雷蒂库林缺乏会损害细胞粘附性和对整合素功能至关重要的流入.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 集成蛋白调解细胞粘附和信号传导.
- 卡尔雷丘林与整合素α子单元相互作用,影响细胞粘附.
- 了解calreticulin在整合素功能中的作用至关重要.
研究的目的:
- 调查卡尔雷蒂库林在因特林介导的细胞粘附和信号传递中的作用.
- 为了确定calreticulin对因整合素接触引发的过渡体的影响.
主要方法:
- 胚胎干细胞 (ES) 和纤维细胞 (Fibroblasts) 缺乏卡莱蒂库林的发展.
- 评估野生类型和缺卡莱蒂库林细胞中的整合素介导粘附.
- 在整合素接触时分析细胞质度的变化.
主要成果:
- 缺乏卡尔雷蒂库林的细胞表现出严重受损的整体因子介导的粘附.
- 在没有calreticulin的情况下,整体蛋白表达保持不变.
- 卡尔雷蒂库林缺乏消除了通常由整合素接触引起的过渡性,而不会影响内膜储量.
结论:
- 卡尔雷蒂库林是整合素粘合功能的重要调节剂.
- 卡尔雷蒂库林在整合素启动的信号通路,特别是流入中发挥着关键作用.
- 卡尔雷蒂库林并没有显著地参与光线的储存.
相关概念视频
Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
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Integrins
Animal and protozoan cells do not have cell walls to help maintain shape and provide structural stability. Instead, these eukaryotic cells secrete a sticky mass of carbohydrates and proteins into the spaces between adjacent cells. This network of proteins and molecules is called an extracellular matrix or ECM.
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
Activation of Integrins
Integrins bind ligands and transmit information from outside the cell to inside or vice-versa through an "outside-in signaling" or "inside-out signaling."
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
Intracellular Signaling Affects Focal Adhesions
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
Some...
Adherens Junctions
Strong contact points between adjacent cells anchor them to each other, forming tissues. Such anchoring junctions are of two types – adherens junctions and desmosomes. Adherens junctions are abundant in tissues such as epithelium and endothelium, forming a continuous zone of adhesion called the adhesion belt. In other tissues, such as heart muscle, they appear as clusters, linking the cells to produce coordinated heart muscle contraction.
Adherens Junctions are Dynamic
The endothelial cells...
Adherens Junctions are Dynamic
The endothelial cells...
Immunoglobulin-like Cell Adhesion Molecules
Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...


