Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.
School of Engineering Science, University of Chinese Academy of Sciences, Beijing, 100049, China.
Biomech Model Mechanobiol. 2021 Feb;20(1):205-222. doi: 10.1007/s10237-020-01378-5. Epub 2020 Aug 18.
Human embryonic stem cells (hESCs) can differentiate to three germ layers within biochemical and biomechanical niches. The complicated mechanical environments in vivo could have diverse effects on the fate decision and biological functions of hESCs. To globally screen mechanosensitive molecules, three typical types of mechanical stimuli, i.e., tensile stretch, shear flow, and mechanical compression, were applied in respective parameter sets of loading pattern, amplitude, frequency, and/or duration, and then, iTRAQ proteomics test was used for identifying and quantifying differentially expressed proteins in hESCs. Bioinformatics analysis identified 37, 41, and 23 proteins under stretch pattern, frequency, and duration, 13, 18, and 41 proteins under shear pattern, amplitude, and duration, and 4, 0, and 183 proteins under compression amplitude, frequency, and duration, respectively, where distinct parameters yielded the differentially weighted preferences under each stimulus. Ten mechanosensitive proteins were commonly shared between two of three mechanical stimuli, together with numerous proteins identified under single stimulus. More importantly, functional GSEA and WGCNA analyses elaborated the variations of the screened proteins with loading parameters. Common functions in protein synthesis and modification were identified among three stimuli, and specific functions were observed in skin development under stretch alone. In conclusion, mechanomics analysis is indispensable to map actual mechanosensitive proteins under physiologically mimicking mechanical environment, and sheds light on understanding the core hub proteins in mechanobiology.
人类胚胎干细胞（hESCs）可以在生化和生物力学小生境中分化为三个胚层。体内复杂的机械环境可能对 hESC 的命运决定和生物学功能产生多样化的影响。为了全面筛选机械敏感分子，我们在各自的加载模式、幅度、频率和/或持续时间参数集中应用了三种典型的机械刺激类型，即拉伸拉伸、剪切流和机械压缩，然后使用 iTRAQ 蛋白质组学测试来识别和定量 hESC 中差异表达的蛋白质。生物信息学分析分别在拉伸模式、频率和持续时间下鉴定出 37、41 和 23 个蛋白，在剪切模式、幅度和持续时间下鉴定出 13、18 和 41 个蛋白，在压缩幅度、频率和持续时间下鉴定出 4、0 和 183 个蛋白，其中不同的参数在每种刺激下产生了不同权重的偏好。十种机械敏感蛋白在三种机械刺激中的两种之间共有，与单一刺激下鉴定出的大量蛋白一起。更重要的是，功能 GSEA 和 WGCNA 分析详细阐述了筛选出的蛋白随加载参数的变化。在三种刺激中鉴定到了蛋白质合成和修饰的共同功能，并且仅在拉伸刺激下观察到了皮肤发育的特定功能。总之，力学组学分析对于在生理模拟的机械环境下绘制实际的机械敏感蛋白图谱是不可或缺的，并为理解力学生物学中的核心枢纽蛋白提供了思路。
