Stable lineages, rewired landscapes: single-cell and spatial multi-omics reveal developmental plasticity under abiotic stress.

内容摘要

Plants are constantly challenged by environmental stressors, yet their sessile nature demands highly flexible developmental programs to maintain growth and survival. With the advent of single-cell technologies, developmental plasticity can now be dissected at cellular resolution. Two recent Populus studies show that both mechanical and drought stress induce xylem remodeling by shifting cell-type ratios or altering differentiation speed, while preserving the underlying developmental lineages. Highly similar patterns have been recently observed in Arabidopsis and cabbage, in which osmotic and salt stress alter the tempo of root hair differentiation without changing lineage identity. The recurrence of this developmental program across woody and herbaceous species, spanning distinct taxonomic orders, suggests that lineage-stable yet flexible stress responses are evolutionarily conserved in plants. Moreover, these insights were enabled by the application of advanced single-cell and spatially resolved approaches, with several of these studies incorporating single-cell/nucleus transcriptomics with spatial multi-omics analyses to link developmental dynamics with tissue context. This balance between flexibility and developmental order may represent a fundamental principle by which plants maintain resilience under diverse environmental challenges and may offer a valid framework for this field of study. 植物在生長過程中持續面臨各種環境逆境挑戰；然而，由於其固著性的生長特性，植物必須仰賴高度可塑性的發育調控，以維持生存與適應環境變化。隨著單細胞技術的快速發展，植物發育可塑性如今已能在單細胞層級被深入解析。近期兩篇以楊樹為研究對象的研究顯示，機械應力與乾旱逆境皆可透過改變細胞類型比例，或調節細胞分化速度，誘導木質部發育重塑；然而，這些變化仍維持既有的發育譜系結構。類似現象近期亦在阿拉伯芥與不結球白菜中被觀察到，分別顯示滲透壓與鹽逆境可改變根毛分化的發育節奏，但不改變其原有細胞譜系。此類現象同時出現在木本與草本植物中，且橫跨不同演化類群，顯示「維持細胞譜系穩定、同時保有發育可塑性」的逆境反應模式，為植物適應環境變化時的一種演化保守策略。此觀點的建立亦有賴於先進單細胞與空間解析技術的應用；透過結合單細胞/細胞核及空間轉錄體學，或是應用質譜多體學於獲取空間分子資訊，得以將發育動態與組織空間脈絡相互連結，進一步理解植物如何在逆境下維持發育進程與生長韌性。.