PDF(Pubmed)
Abstract：
Rice production accounts for approximately half of the freshwater resources utilized in agriculture, resulting in greenhouse gas emissions such as methane (CH4) from flooded paddy fields. To address this challenge, environmentally friendly and cost-effective water-saving techniques have become widely adopted in rice cultivation. However, the implementation of water-saving treatments (WSTs) in paddy-field rice has been associated with a substantial yield loss of up to 50% as well as a reduction in nitrogen use efficiency (NUE). In this study, we discovered that the target of rapamycin (TOR) signaling pathway is compromised in rice under WST. Polysome profiling-coupled transcriptome sequencing (polysome-seq) analysis unveiled a substantial reduction in global translation in response to WST associated with the downregulation of TOR activity. Molecular, biochemical, and genetic analyses revealed new insights into the impact of the positive TOR-S6K-RPS6 and negative TOR-MAF1 modules on translation repression under WST. Intriguingly, ammonium exhibited a greater ability to alleviate growth constraints under WST by enhancing TOR signaling, which simultaneously promoted uptake and utilization of ammonium and nitrogen allocation. We further demonstrated that TOR modulates the ammonium transporter AMT1;1 as well as the amino acid permease APP1 and dipeptide transporter NPF7.3 at the translational level through the 5\' untranslated region. Collectively, these findings reveal that enhancing TOR signaling could mitigate rice yield penalty due to WST by regulating the processes involved in protein synthesis and NUE. Our study will contribute to the breeding of new rice varieties with increased water and fertilizer utilization efficiency.
摘要：
水稻产量约占农业利用的淡水资源的一半，导致淹没稻田的甲烷（CH4）等温室气体排放。为了应对这一挑战，环保和经济有效的节水技术已在水稻种植中广泛采用。然而,在水稻中实施节水处理（WST）与高达50％的大量产量损失以及氮利用效率（NUE）的降低有关。在这项研究中,我们发现在WST条件下，水稻中雷帕霉素（TOR）信号通路的靶标受到了损害。通过多聚体谱分析偶联转录组测序（polysome-seq）分析，我们观察到与TOR活性下调相关的WST的全球翻译显著减少.分子,生物化学，遗传分析揭示了对阳性TOR-S6K-RPS6和阴性TOR-MAF1模块对WST下翻译抑制的影响的新见解。有趣的是，铵通过增强TOR信号传导表现出更大的缓解WST下生长限制的能力，同时促进了铵和氮分配的吸收和利用。我们进一步证明，TOR通过5'非翻译区（5'UTR）在翻译水平上调节铵转运蛋白AMT1;1以及氨基酸通透酶APP1和二肽转运蛋白NPF7.3。总的来说，这些发现表明，增强TOR信号可以通过调节蛋白质合成和NUE的过程来减轻WST导致的水稻产量损失。本研究将有助于选育提高水肥利用率的水稻新品种。
