Many cellular processes are orchestrated by dynamic changes in the plasma membrane to form membrane projections and endocytic vesicles in response to extracellular environmental changes. Our previous studies show that ARF6-ACAP4-ezrin signaling regulates membrane dynamics and curvature in response to EGF stimulation. However, there is no quantitative measurement to relate molecular organization of membrane cytoskeletal remodeling to stimulus-elicited mechanosensation on the plasma membrane. Optical tweezers is a powerful tool in the study of membrane tension. Comparing to pulling out an entire membrane tether at one time, the step-like method is more efficient because multiple relaxation curves can be obtained from one membrane tether. Fewer models describe relaxation curves to characterize mechanical properties of cell membrane. Here we establish a new method to measure the membrane relaxation curve of HeLa cells judged by the relationship between membrane tether diameter and tensions. We obtained effective viscosities and static tensions by fitting relaxation curves to our model. We noticed the delicate structure of relaxation curves contains information of cytoskeletal remodeling and lateral protein diffusion. Our study established a quantitative measure to characterize the mechanosensation of epithelial cells in response to stimulus-elicited membrane dynamics.

中文翻译：

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使用光镊测量动态膜机械感觉。

许多细胞过程是由质膜的动态变化协调的，以响应细胞外环境变化形成膜投射和内吞囊泡。我们之前的研究表明，ARF6-ACAP4-ezrin 信号调节膜动力学和曲率以响应 EGF 刺激。然而，没有定量测量将膜细胞骨架重塑的分子组织与质膜上刺激引发的机械感觉联系起来。光镊是研究膜张力的有力工具。与一次拉出整个膜系绳相比，阶梯式方法更有效，因为可以从一个膜系绳获得多条弛豫曲线。更少的模型描述松弛曲线来表征细胞膜的机械特性。在这里，我们建立了一种新的方法来测量HeLa细胞的膜松弛曲线，通过膜系绳直径和张力之间的关系来判断。我们通过将松弛曲线拟合到我们的模型来获得有效的粘度和静态张力。我们注意到松弛曲线的精细结构包含细胞骨架重塑和横向蛋白质扩散的信息。我们的研究建立了一种定量测量方法来表征上皮细胞响应刺激引发的膜动力学的机械感觉。我们注意到松弛曲线的精细结构包含细胞骨架重塑和横向蛋白质扩散的信息。我们的研究建立了一种定量测量方法来表征上皮细胞响应刺激引发的膜动力学的机械感觉。我们注意到松弛曲线的精细结构包含细胞骨架重塑和横向蛋白质扩散的信息。我们的研究建立了一种定量测量方法来表征上皮细胞响应刺激引发的膜动力学的机械感觉。