Guo Yuanlong, Ao Yong, Ye Chen, Xia Ruidi, Mi Jiaomei, Shan Zhengjie, Shi Mengru, Xie Lv, Chen Zetao
Hospital of Stomatology, Sun Yat-sen University and Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, 510055 China.
Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 China.
Nano Res. 2023 Mar 5:1-15. doi: 10.1007/s12274-023-5550-0.
Finely tuning mechanosensitive membrane proteins holds great potential in precisely controlling inflammatory responses. In addition to macroscopic force, mechanosensitive membrane proteins are reported to be sensitive to micro-nano forces. Integrin , for example, might undergo a piconewton scale stretching force in the activation state. High-aspect-ratio nanotopographic structures were found to generate nN-scale biomechanical force. Together with the advantages of uniform and precisely tunable structural parameters, it is fascinating to develop low-aspect-ratio nanotopographic structures to generate micro-nano forces for finely modulating their conformations and the subsequent mechanoimmiune responses. In this study, low-aspect-ratio nanotopographic structures were developed to finely manipulate the conformation of integrin β. The direct interaction of forces and the model molecule integrin α was first performed. It was demonstrated that pressing force could successfully induce conformational compression and deactivation of integrin α, and approximately 270 to 720 pN may be required to inhibit its conformational extension and activation. Three low-aspect-ratio nanotopographic surfaces (nanohemispheres, nanorods, and nanoholes) with various structural parameters were specially designed to generate the micro-nano forces. It was found that the nanorods and nanohemispheres surfaces induce greater contact pressure at the contact interface between macrophages and nanotopographic structures, particularly after cell adhesion. These higher contact pressures successfully inhibited the conformational extension and activation of integrin β, suppressing focal adhesion activity and the downstream PI3K-Akt signaling pathway, reducing NF-B signaling and macrophage inflammatory responses. Our findings suggest that nanotopographic structures can be used to finely tune mechanosensitive membrane protein conformation changes, providing an effective strategy for precisely modulating inflammatory responses.
Supplementary material (primer sequences of target genes in RT-qPCR assay; the results of solvent accessible surface area during equilibrium simulation, the ligplut results of hydrogen bonds, and hydrophobic interactions; the density of different nanotopographic structures; interaction analysis of the downregulated leading genes of "focal adhesion" signaling pathway in nanohemispheres and nanorods groups; and the GSEA results of "Rap 1 signaling pathway" and "regulation of actin cytoskeleton" in different groups) is available in the online version of this article at 10.1007/s12274-023-5550-0.
精确调控机械敏感膜蛋白在精确控制炎症反应方面具有巨大潜力。除了宏观力之外，据报道机械敏感膜蛋白对微纳米力也很敏感。例如，整合素在激活状态下可能会受到皮牛顿尺度的拉伸力。人们发现高纵横比的纳米拓扑结构会产生纳牛顿尺度的生物力学力。鉴于其结构参数具有均匀且可精确调节的优点，开发低纵横比的纳米拓扑结构以产生微纳米力来精细调节其构象及随后的机械免疫反应是很有吸引力的。在本研究中，开发了低纵横比的纳米拓扑结构来精细操纵整合素β的构象。首先进行了力与模型分子整合素α的直接相互作用研究。结果表明，压力能够成功诱导整合素α的构象压缩和失活，抑制其构象伸展和激活可能需要约270至720皮牛顿的力。特别设计了具有不同结构参数的三种低纵横比纳米拓扑表面（纳米半球、纳米棒和纳米孔）以产生微纳米力。研究发现，纳米棒和纳米半球表面在巨噬细胞与纳米拓扑结构的接触界面处会诱导更大的接触压力，尤其是在细胞黏附后。这些更高的接触压力成功抑制了整合素β的构象伸展和激活，抑制了粘着斑活性和下游PI3K - Akt信号通路，降低了NF - B信号传导和巨噬细胞炎症反应。我们的研究结果表明，纳米拓扑结构可用于精细调节机械敏感膜蛋白的构象变化，为精确调控炎症反应提供了一种有效策略。
补充材料（RT - qPCR分析中靶基因引物序列；平衡模拟过程中溶剂可及表面积结果、氢键和疏水相互作用的ligplut结果；不同纳米拓扑结构的密度；纳米半球和纳米棒组中“粘着斑 ”信号通路下调的主导基因的相互作用分析；以及不同组中“Rap 1信号通路”和“肌动蛋白细胞骨架调控”的GSEA结果）可在本文的在线版本中获取，链接为10.1007/s1Z274 - 023 - 5550 - 0。
