Investigating E-cadherin Mechanotransduction

项目摘要/摘要 所有细胞都会受到力的作用。这些力由细胞表面黏附受体感知，并触发强大的 肌动蛋白细胞骨架的重排和生长相关的黏附复合体，以对抗外力。 这一过程被称为细胞加固或加固。强化所需的肌动蛋白重排是 能源成本高昂，这表明力传递和能量产生的耦合机制是存在的。 此前，我们的实验室发现了一种力传递和能量利用的耦合机制。我们 证明，作为对压力的响应，AMPK在E-钙粘附素黏附复合体上被招募和激活， 从而刺激肌动球蛋白的收缩、葡萄糖摄取和ATP的产生。这种葡萄糖的增加 摄取和ATP提供生长黏附复合体和加强肌动蛋白所需的能量 细胞骨架。尽管如此，机械力是如何调节葡萄糖摄取和葡萄糖的 对新陈代谢的了解还不完全。本研究旨在确定葡萄糖转运蛋白1(GLUT1)是如何影响 力诱导的代谢变化和细胞僵硬。这里我们认为GLUT1是力敏感的葡萄糖 负责黏附复合体生长所必需的葡萄糖摄取的转运体 肌动蛋白细胞骨架的强化。为了进一步支持这一概念，我们表明GLUT1被招募到 细胞-细胞连接，并与E-钙粘附素形成复合体，以响应压力。此外，我们提出了证据 GLUT1的抑制阻止了力诱导的细胞僵硬。这项研究中拟议工作的第二个目标是 评估葡萄糖代谢如何与E-钙粘附素介导的细胞骨架重排相偶联。多重 糖酵解酶与丝状肌动蛋白(F-肌动蛋白)结合，如醛缩酶和磷酸果糖激酶-1。 先前的研究表明，在胰岛素刺激下肌动蛋白会释放F-肌动蛋白结合的醛缩酶 改建。我们认为，对E-钙粘附素施加力可以导致F-肌动蛋白结合的糖酵解释放 酶，如醛缩酶和PFK。此外，我们怀疑胞浆中这些酶的释放 糖酵解的增加和定位，这是力诱导能量产生所必需的。这项研究提出 糖代谢与力诱导细胞能量密集型过程之间的新联系 变得僵硬。

Project Summary/Abstract All cells experience force. These forces are sensed by cell surface adhesion receptors and trigger robust actin cytoskeletal rearrangements and growth of the associated adhesion complex to counter the applied forces. This process is known as cell stiffening or reinforcement. The actin re-arrangements necessary for stiffening are energetically costly suggesting that mechanisms coupling force transduction and energy production exist. Previously our laboratory identified a mechanism for coupling force transmission and energy utilization. We demonstrated that, in response to force, AMPK is recruited and activated at the E-cadherin adhesion complexes, thereby stimulating actomyosin contractility, glucose uptake, and ATP production. This increase in glucose uptake and ATP provides the energy necessary to grow the adhesion complexes and reinforce the actin cytoskeleton. Despite this advancement, how mechanical force modulates glucose uptake and glucose metabolism is not fully understood. This study aims to determine how glucose transporter-1 (GLUT1) affects force-induced metabolic changes and cell stiffening. Here we suggest that GLUT1 is the force-sensitive glucose transporter responsible for the glucose uptake necessary for the growth of adhesion complexes and reinforcement of the actin cytoskeleton. In further support of this notion, we show that GLUT1 is recruited to the cell-cell junctions and forms a complex with E-cadherin in response to force. Furthermore, we present evidence that inhibition of GLUT1 blocks force-induced cell stiffening. A second goal of the proposed work in this study is to assess how glucose metabolism is coupled to E-cadherin mediated cytoskeleton rearrangements. Multiple glycolytic enzymes are bound to filamentous actin (F-actin), such as aldolase and phosphofructokinase-1. Previous studies have demonstrated that F-actin bound aldolase is released upon insulin stimulated actin remodeling. We propose that the application of force to E-cadherin causes the release of F-actin-bound glycolytic enzymes, such as aldolase and PFK. Additionally, we suspect that cytosolic release of these enzymes mediates the increase and localization of glycolysis, necessary for force-induced energy production. This study proposes a novel connection between glucose metabolism and the energy-intensive process of force-induced cell stiffening.