College of Life Sciences, National Key Laboratory of Wheat Improvement, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
Agricultural Science and Engineering School, Liaocheng University, Liaocheng, Shandong, 252000, China.
New Phytol. 2023 Oct;240(1):338-353. doi: 10.1111/nph.19129. Epub 2023 Jul 10.
Identifying new nitrate regulatory genes and illustrating their mechanisms in modulating nitrate signaling are of great significance for achieving the high yield and nitrogen use efficiency (NUE) of crops. Here, we screened a mutant with defects in nitrate response and mapped the mutation to the gene eIF4E1 in Arabidopsis. Our results showed that eIF4E1 regulated nitrate signaling and metabolism. Ribo-seq and polysome profiling analysis revealed that eIF4E1 modulated the amount of some nitrogen (N)-related mRNAs being translated, especially the mRNA of NRT1.1 was reduced in the eif4e1 mutant. RNA-Seq results enriched some N-related genes, supporting that eIF4E1 is involved in nitrate regulation. The genetic analysis indicated that eIF4E1 worked upstream of NRT1.1 in nitrate signaling. In addition, an eIF4E1-interacting protein GEMIN2 was identified and found to be involved in nitrate signaling. Further investigation showed that overexpression of eIF4E1 promoted plant growth and enhanced yield and NUE. These results demonstrate that eIF4E1 regulates nitrate signaling by modulating NRT1.1 at both translational and transcriptional levels, laying the foundation for future research on the regulation of mineral nutrition at the translational level.
鉴定新的硝酸盐调控基因，并阐明其调控硝酸盐信号的机制，对于实现作物的高产和氮素利用效率（NUE）具有重要意义。在这里，我们筛选到一个硝酸盐响应缺陷的突变体，并将该突变定位到拟南芥中的基因 eIF4E1。我们的结果表明，eIF4E1 调控硝酸盐信号和代谢。核糖体 RNA 测序和多核糖体分析表明，eIF4E1 调节一些与氮（N）相关的 mRNA 的翻译量，特别是 eif4e1 突变体中 NRT1.1 的 mRNA 减少。RNA-Seq 结果富集了一些与 N 相关的基因，支持 eIF4E1 参与硝酸盐的调控。遗传分析表明，eIF4E1 在硝酸盐信号转导中位于 NRT1.1 的上游。此外，鉴定到一个 eIF4E1 互作蛋白 GEMIN2，并发现其参与硝酸盐信号转导。进一步的研究表明，eIF4E1 的过表达促进了植物的生长，提高了产量和 NUE。这些结果表明，eIF4E1 通过在翻译和转录水平上调节 NRT1.1 来调控硝酸盐信号，为未来在翻译水平上研究矿物质营养的调控奠定了基础。
