PIEZO-dependent mechano-sensing of the niche is essential for intestinal stem cell fate decision and maintenance. PIEZO-dependent mechano-sensing of the niche is essential for intestinal stem cell fate decision and maintenance

Stem cells perceive and respond to biochemical and physical signals to maintain homeostasis. Yet, it remains unclear how stem cells sense mechanical signals from their niche in vivo. Here, we investigated the roles of PIEZO mechanosensitive channels in intestinal stem cell (ISC) niche. By employing mouse genetics and single-cell RNAseq analysis, we revealed the requirement for PIEZO channels in ISC maintenance. In vivo measurement of basement membrane stiffness showed that ISCs reside in a more rigid microenvironment at the bottom of the crypt. Using 3D and 2D organoid systems combined with bioengineered substrates and stretching device, we found that PIEZO sense extracellular mechanical stimuli to modulate ISC function. This study delineates the mechanistic cascade of PIEZO activation that coordinates ISC fate decision and maintenance. Overall design: Crypt were isolated and pooled from 3 control and Piezo-deleted mice.

干细胞可感知并响应生化与物理信号，以维持机体稳态。然而目前仍不清楚干细胞在体内如何感知来自其干细胞龛的机械信号。本研究针对PIEZO机械敏感性离子通道（PIEZO mechanosensitive channels）在肠道干细胞（intestinal stem cell, ISC）龛中的作用展开探究。本研究采用小鼠遗传学技术与单细胞RNA测序（single-cell RNAseq）分析，阐明了PIEZO通道在肠道干细胞维持过程中的必需性。通过对基底膜（basement membrane）硬度的体内检测，我们发现肠道干细胞定位于肠隐窝底部刚度更高的微环境中。我们结合三维、二维类器官（organoid）系统与生物工程基质、拉伸装置开展实验，发现PIEZO通道可感知细胞外机械刺激，进而调控肠道干细胞的功能。本研究阐明了PIEZO通道激活的信号级联反应，该反应可协调肠道干细胞的命运决定与维持过程。实验设计：从3只对照组小鼠与3只Piezo基因敲除小鼠中分离肠隐窝并进行样本混合。