Yamashiro Sawako, Nomura Misato, Chapin Nils, Sasidharan Sreeja, Elverston Louis, Knepper Leah, Thévenin Damien, Watanabe Naoki, Honerkamp-Smith Aurelia R
Laboratory of Single-Molecule Cell Biology, Kyoto University Graduate School of Biostudies, Kyoto Japan.
Department of Pharmacology, Kyoto University Graduate School of Medicine, Kyoto Japan.
bioRxiv. 2025 Aug 29:2025.08.27.672548. doi: 10.1101/2025.08.27.672548.
Cells sense and respond to fluid shear stress. Cell surfaces are exposed to flow, yet the influence of shear stress on the behavior of plasma membrane proteins remains unclear. Here we show that extracellular flow induces the gradient distribution of cell membrane proteins with increasing concentration toward the downstream direction of the flow. Shear stress at 10-30 dynes/cm caused formation of concentration gradients of both GPI-anchored proteins and transmembrane proteins, including integrinß1, E-cadherin and the insulin receptor in XTC cells. Using single-molecule live-cell imaging, we found that GPI-anchored T-cadherin molecules are dragged along the direction of flow under shear stress. In addition, shear stress induced concentration gradients of membrane proteins in COS-7 cells and human umbilical vein endothelial cells (HUVECs). Our findings suggest that external flow directly transports membrane proteins, establishing concentration gradients that may contribute to the cellular flow-sensing mechanism.
细胞能够感知并对流体剪切应力作出反应。细胞表面会暴露于流动之中，然而剪切应力对质膜蛋白行为的影响仍不清楚。在此我们表明，细胞外流动会诱导细胞膜蛋白呈梯度分布，其浓度朝着流动的下游方向增加。10 - 30达因/平方厘米的剪切应力导致XTC细胞中糖基磷脂酰肌醇（GPI）锚定蛋白和跨膜蛋白（包括整合素β1、E - 钙黏蛋白和胰岛素受体）形成浓度梯度。通过单分子活细胞成像，我们发现GPI锚定的T - 钙黏蛋白分子在剪切应力作用下沿流动方向被拖动。此外，剪切应力在COS - 7细胞和人脐静脉内皮细胞（HUVECs）中诱导了膜蛋白的浓度梯度。我们的研究结果表明，外部流动直接运输膜蛋白，建立起可能有助于细胞流动感知机制的浓度梯度。
