Department of Biology, Stanford University, Stanford, United States.
Howard Hughes Medical Institute, Stanford University, Stanford, United States.
Elife. 2021 Mar 19;10:e63335. doi: 10.7554/eLife.63335.
Asymmetric and self-renewing divisions build and pattern tissues. In the Arabidopsis stomatal lineage, asymmetric cell divisions, guided by polarly localized cortical proteins, generate most cells on the leaf surface. Systemic and environmental signals modify tissue development, but the mechanisms by which plants incorporate such cues to regulate asymmetric divisions are elusive. In a screen for modulators of cell polarity, we identified , a negative regulator of ethylene signaling. We subsequently revealed antagonistic impacts of ethylene and glucose signaling on the self-renewing capacity of stomatal lineage stem cells. Quantitative analysis of cell polarity and fate dynamics showed that developmental information may be encoded in both the spatial and temporal asymmetries of polarity proteins. These results provide a framework for a mechanistic understanding of how nutritional status and environmental factors tune stem-cell behavior in the stomatal lineage, ultimately enabling flexibility in leaf size and cell-type composition.
不对称和自我更新的分裂构建和塑造组织。在拟南芥气孔谱系中，由极性定位的皮质蛋白引导的不对称分裂产生叶片表面的大多数细胞。系统和环境信号改变组织发育，但植物将这些线索纳入调节不对称分裂的机制仍难以捉摸。在筛选细胞极性调节剂时，我们鉴定出了一个乙烯信号的负调节剂。我们随后揭示了乙烯和葡萄糖信号对气孔谱系干细胞自我更新能力的拮抗影响。细胞极性和命运动态的定量分析表明，发育信息可能编码在极性蛋白的空间和时间不对称中。这些结果为理解营养状况和环境因素如何调节气孔谱系中干细胞行为提供了一个机制框架，最终使叶片大小和细胞类型组成具有灵活性。
