Stem cell populations in all multicellular organisms are situated in a niche, which is a special microenvironment that defines stem cell fate. The interplay between stem cells and their niches is crucial for stem cell maintenance. Here, we show that an endogenous stress-related signal (ESS) is overrepresented in the shoot stem cell niche under natural growth conditions, and the vast majority of known stem-cell-specific and niche-specific genes responded to stress signals. Interference with the ESS in the stem cell niche by blocking ethylene signalling impaired stem cell maintenance. Ethylene-insensitive 3 (EIN3), the key transcription factor in ethylene signalling, directly actives the expression of the stress hub transcription factor AGAMOUS-LIKE 22 (AGL22) in the stem cell niche and relays ESS signals to the WUSCHEL/CLAVATA network. Our results provide a mechanistic framework for ESS signalling control of the stem cell niche and demonstrate that plant stem cells are maintained by a native stress microenvironment in vivo.

所有多细胞生物中的干细胞群都位于一个生态位中，这是一个决定干细胞命运的特殊微环境。干细胞与其生态位之间的相互作用对于干细胞的维持至关重要。在这里，我们表明，在自然生长条件下，内源性应激相关信号 (ESS) 在芽干细胞生态位中过度表达，并且绝大多数已知的干细胞特异性和生态位特异性基因对应激信号有反应。通过阻断乙烯信号干扰干细胞生态位中的 ESS 会损害干细胞的维持。乙烯不敏感 3 (EIN3) 是乙烯信号传导中的关键转录因子，直接激活应激枢纽转录因子AGAMOUS-LIKE 22 ( AGL22) 在干细胞生态位中并将 ESS 信号中继到 WUSCHEL/CLAVATA 网络。我们的研究结果为干细胞生态位的 ESS 信号控制提供了一个机制框架，并证明植物干细胞是由体内的天然应激微环境维持的。