DELAY OF GERMINATION 1, the Master Regulator of Seed Dormancy, Integrates the Regulatory Network of Phytohormones at the Transcriptional Level to Control Seed Dormancy

Abstract

Seed dormancy, an important adaptive trait that governs germination timing, is endogenously controlled by phytohormones and genetic factors. DELAY OF GERMINATION 1 (DOG1) is the vital genetic regulator of dormancy, significantly affecting the expression of numerous ABA and GA metabolic genes. However, whether DOG1 could influence the expression of other phytohormone-related genes is still unknown. Here, we comprehensively investigated all well-documented hormone-related genes which might be affected in dog1–2 dry or imbibed seeds by using whole-transcriptome sequencing (RNA-seq). We found that DOG1 could systematically control the expression of phytohormone-related genes. An evident decrease was observed in the endogenous signal intensity of abscisic acid (ABA) and indole-3-acetic acid (IAA), while a dramatic increase appeared in that of gibberellins (GA), brassinosteroids (BR), and cytokinin (CK) in the dog1–2 background, which may contribute considerably to its dormancy-deficient phenotype. Collectively, our data highlight the role of DOG1 in balancing the expression of phytohormone-related genes and provide inspirational evidence that DOG1 may integrate the phytohormones network to control seed dormancy.

种子萌发调控的研究进展

“…此外, ERF12 (ETHYLENE RESPONSE FACTOR 12)及其下游靶子 ETR1 (ETHYLENE RESPONSE1)直接与 DOG1 启动子结合并招募 TPL (TOPLESS), 导致 DOG1 被抑制, 表明乙烯也通过 ETR1-ERF12/TPL-DOG1 模块调控种子休眠 [209] . Li 等 [210] 的 研究表明, 在 dog1-2 背景下, ABA 和 IAA 的内源信号强度明显降低, 而 GA、BR 和细胞分 裂素的内源信号强度显著增加; 这可能是其休眠缺陷表型的重要原因. 他们强调了 DOG1 在 平衡植物激素相关基因表达中的作用, 并提供了 DOG1 可能整合植物激素网络来控制种子 休眠的证据.…”