2026-04-09 中国科学院（CAS）
＜関連情報＞
- https://english.cas.cn/newsroom/research-news/202604/t20260409_1155591.shtml
- https://www.sciencedirect.com/science/article/pii/S0926669026004188
単一核トランスクリプトミクスにより、トウダイグサ（Euphorbia lathyris L）における乳管特異的な転写プログラムとトリテルペノイド-ゴム代謝協調が明らかになった Single-nucleus transcriptomics reveals laticifer-specific transcriptional programs and triterpenoid-rubber metabolic coordination in Euphorbia lathyris L
Fang Liu, Xue Zhang, Yanhong Xu, Liqi Liang, Zhijia Gu, Yuqian Ma, Yanxiong Pan, Rui Li, Lin Xu, Chun-Peng Song, David W. Galbraith, Jinling Huang, Yongping Yang, Jinjing Pan, Guiling Sun
Industrial Crops and Products Available online 14 March 2026
DOI:https://doi.org/10.1016/j.indcrop.2026.123031
Graphical Abstract
Highlights
- snRNA-seq resolves the differentiation trajectory of E. lathyris laticifers.
- Morphology, ultrastructure and size profiling define rubber particles in E. lathyris.
- NR-related genes are fewer and weaker expressed than in Hevea laticifers.
- Rubber and triterpenoid biosynthesis are co-activated in laticifers.
- ElCOG1 negatively regulates both rubber and triterpenoid synthesis.
Abstract
Laticifers are specialized secretory cells that synthesize and store latex and provide a model for studying cellular specialization in plant metabolism. Euphorbia lathyris L. possesses non-articulated laticifers that produce triterpenoid-rich latex, but the mechanistic basis of laticifer specialization and latex metabolism remains unclear. Here, we generate the single-nucleus transcriptomic landscape of E. lathyris leaves and resolve a continuous laticifer trajectory with progressive activation of the mevalonate-derived triterpenoid pathway. Genes encoding the rubber biosynthetic complex, including cis–prenyltransferase (CPT), CPT-binding protein (CBP), and small rubber particle protein (SRPP), were specifically expressed in laticifers, indicating potential rubber formation. Ultrastructural and chemical analyses detect small rubber particles (∼150 nm) and a low-abundance cis-1,4-polyisoprene fraction in latex (0.30–0.47% w/w) with short average chain length (Mw ≈ 150–180 kDa). The streamlined repertoire of rubber biosynthetic pathway genes and the absence of Hevea-like rubber elongation factors (REFs) may be associated with the observed low rubber content and smaller molecular weight in E. lathyris. Network inference and validation identified a laticifer-specific DOF transcription factor, COGWHEEL1 (ElCOG1), that binds the promoters of ElCPT1 and butyrospermol synthase 1 (ElBUT1) and represses their activity, indicating a shared negative transcriptional control point acting on both the rubber-elongation and triterpenoid branches. In summary, this single-nucleus transcriptomic landscape of E. lathyris laticifers clarifies their metabolic specialization and establishes a framework for dissecting the regulatory programs of specialized secretory cells in latex-bearing plants.
