Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.
College of Grassland Science, Nanjing Agricultural University, Nanjing 210095, China.
Plant Cell Physiol. 2023 Jul 17;64(7):814-825. doi: 10.1093/pcp/pcad041.
Floods impose detrimental effects on natural and agro-ecosystems, leading to a significant loss of worldwide crop production. Global climate change has even worsened this situation. Flooding is a continuous process including two stages of submergence and re-oxygenation, and both are harmful to plant growth and development, resulting in a serious decline in crop yield. Therefore, the understanding of plant flooding tolerance and developing flooding-resistant crops are of great significance. Here, we report that the Arabidopsis thaliana (Arabidopsis) R2R3-MYB transcription factor MYB30 participates in plant submergence response through 1-aminocyclopropane-1-carboxylic acid synthase 7 (ACS7) by repressing ethylene (ET) biosynthesis. The MYB30 loss-of-function mutant exhibits reduced submergence tolerance with a higher level of ET production, whereas the MYB30-overexpressing plant displays enhanced submergence tolerance and repressed ET production. The coding gene of ACS7 might be a direct target of MYB30 during the submergence response. MYB30 binds to the promoter of ACS7 and represses its transcription. The ACS7 loss-of-function mutant with defect in ET biosynthesis displays enhanced submergence tolerance, whereas plants overexpressing ACS7 exhibit a submergence-sensitive phenotype. Genetic analysis shows that ACS7 functions downstream of MYB30 in both ET biosynthesis and submergence response. Taken together, our work revealed a novel transcriptional regulation that modulates submergence response in plants.
洪水对自然和农业生态系统造成不利影响，导致全球作物产量的大量损失。全球气候变化甚至使这种情况恶化。洪水是一个连续的过程，包括淹没和再充氧两个阶段，这两个阶段都对植物的生长和发育有害，导致作物产量严重下降。因此，了解植物的耐淹能力并开发耐淹作物具有重要意义。在这里，我们报告称，拟南芥（Arabidopsis）R2R3-MYB 转录因子 MYB30 通过抑制乙烯（ET）生物合成的 1-氨基环丙烷-1-羧酸合酶 7（ACS7）参与植物淹水反应。 MYB30 功能丧失突变体表现出较低的耐淹能力，产生较高水平的 ET，而 MYB30 过表达植物则表现出增强的耐淹能力和抑制的 ET 产生。 ACS7 的编码基因可能是淹水反应中 MYB30 的直接靶标。 MYB30 结合到 ACS7 的启动子上并抑制其转录。 ACS7 功能丧失突变体中 ET 生物合成缺陷，表现出增强的耐淹能力，而 ACS7 过表达植物则表现出淹水敏感表型。遗传分析表明，ACS7 在 ET 生物合成和淹水反应中均作为 MYB30 的下游发挥作用。总之，我们的工作揭示了一种新的转录调控机制，调节植物的淹水反应。
