In plants, N‐acylethanolamines (NAEs) are most abundant in desiccated seeds and their levels decline during germination and early seedling establishment. However, endogenous NAE levels rise in seedlings when ABA or environmental stress is applied, and this results in an inhibition of further seedling development. When the most abundant, polyunsaturated NAEs of linoleic acid (18:2) and linolenic acid (18:3) were exogenously applied, seedling development was affected in an organ‐specific manner. NAE 18:2 primarily affected primary root elongation and NAE 18:3 primarily affected cotyledon greening and expansion and overall seedling growth. The molecular components and signaling mechanisms involved in this pathway are not well understood. In addition, the bifurcating nature of this pathway provides a unique system in which to study the spatial aspects and interaction of these lipid‐specific and organ‐targeted signaling pathways. Using whole transcriptome sequencing (RNA‐seq) and differential expression analysis, we identified early (1–3 hr) transcriptional changes induced by the exogenous treatment of NAE 18:2 and NAE 18:3 in cotyledons, roots, and seedlings. These two treatments led to a significant enrichment in ABA‐response and chitin‐response genes in organs where the treatments led to changes in development. In Arabidopsis seedlings, NAE 18:2 treatment led to the repression of genes involved in cell wall biogenesis and organization in roots and seedlings. In addition, cotyledons, roots, and seedlings treated with NAE 18:3 also showed a decrease in transcripts that encode proteins involved in growth processes. NAE 18:3 also led to changes in the abundance of transcripts involved in the modulation of chlorophyll biosynthesis and catabolism in cotyledons. Overall, NAE 18:2 and NAE 18:3 treatment led to lipid‐type and organ‐specific gene expression changes that include overlapping and non‐overlapping gene sets. These data will provide future, rich opportunities to examine the genetic pathways involved in transducing early signals into downstream physiological changes in seedling growth.

中文翻译：

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亲脂性信号导致拟南芥幼苗器官特异性基因表达变化。


在植物中， N-酰基乙醇胺 (NAE) 在干燥种子中含量最高，其含量在发芽和早期幼苗建立过程中下降。然而，当施加 ABA 或环境胁迫时，幼苗中的内源 NAE 水平会上升，从而抑制幼苗的进一步发育。当外源施用最丰富的多不饱和 NAE 亚油酸 (18:2) 和亚麻酸 (18:3) 时，幼苗发育会受到器官特异性的影响。 NAE 18:2 主要影响主根伸长，NAE 18:3 主要影响子叶绿化和扩张以及整体幼苗生长。该途径涉及的分子成分和信号传导机制尚不清楚。此外，该通路的分叉性质提供了一个独特的系统，可以在其中研究这些脂质特异性和器官靶向信号通路的空间方面和相互作用。利用全转录组测序 (RNA-seq) 和差异表达分析，我们鉴定了子叶、根和幼苗中 NAE 18:2 和 NAE 18:3 的外源处理诱导的早期（1-3 小时）转录变化。这两种治疗导致器官中 ABA 反应和几丁质反应基因显着富集，这些治疗导致了发育的变化。在拟南芥幼苗中，NAE 18:2 处理导致根部和幼苗中参与细胞壁生物发生和组织的基因受到抑制。此外，用 NAE 18:3 处理的子叶、根和幼苗也显示出编码参与生长过程的蛋白质的转录本减少。 NAE 18:3 还导致参与调节子叶中叶绿素生物合成和分解代谢的转录物丰度的变化。总体而言，NAE 18:2 和 NAE 18:3 治疗导致脂质类型和器官特异性基因表达变化，包括重叠和非重叠基因集。这些数据将为研究将早期信号转变成幼苗生长下游生理变化所涉及的遗传途径提供丰富的机会。