Wen Yinyuan, Cheng Liuna, Zhao Zeya, An Mengyao, Zhou Shixue, Zhao Juan, Dong Shuqi, Yuan Xiangyang, Yin Meiqiang
College of Agronomy, Shanxi Agricultural University, Jinzhong, China.
Ministerial and Provincial Co-Innovation Centre for Endemic Crops Production with High-quality and Effciency in Loess Plateau, Jinzhong, China.
Front Plant Sci. 2024 Mar 11;15:1355518. doi: 10.3389/fpls.2024.1355518. eCollection 2024.
Selenium-enriched foxtail millet () represents a functional cereal with significant health benefits for humans. This study endeavors to examine the impact of foliar application of sodium selenite (NaSeO) on foxtail millet, specifically focusing on selenium (Se) accumulation and transportation within various plant tissues.
To unravel the molecular mechanisms governing selenium accumulation and transportation in foxtail millet, we conducted a comprehensive analysis of selenium content and transcriptome responses in foxtail millet spikelets across different days (3, 5, 7, and 12) under NaSeO treatment (200 μmol/L).
Foxtail millet subjected to selenium fertilizer exhibited significantly elevated selenium levels in each tissue compared to the untreated control. Selenate was observed to be transported and accumulated sequentially in the leaf, stem, and spikes. Transcriptome analysis unveiled a substantial upregulation in the transcription levels of genes associated with selenium metabolism and transport, including sulfate, phosphate, and nitrate transporters, ABC transporters, antioxidants, phytohormone signaling, and transcription factors. These genes demonstrated intricate interactions, both synergistic and antagonistic, forming a complex network that regulated selenate transport mechanisms. Gene co-expression network analysis highlighted three transcription factors in the tan module and three transporters in the turquoise module that significantly correlated with selenium accumulation and transportation. Expression of sulfate transporters (SiSULTR1.2b and SiSULTR3.1a), phosphate transporter (PHT1.3), nitrate transporter 1 (NRT1.1B), glutathione S-transferase genes (GSTs), and ABC transporter (ABCC13) increased with SeO accumulation. Transcription factors MYB, WRKY, and bHLH were also identified as players in selenium accumulation.
This study provides preliminary insights into the mechanisms of selenium accumulation and transportation in foxtail millet. The findings hold theoretical significance for the cultivation of selenium-enriched foxtail millet.
富硒谷子是一种对人体健康有益的功能性谷物。本研究旨在探讨叶面喷施亚硒酸钠（NaSeO）对谷子的影响，特别关注硒（Se）在不同植物组织中的积累和运输。
为了揭示调控谷子中硒积累和运输的分子机制，我们对在NaSeO处理（200 μmol/L）下不同天数（3、5、7和12天）的谷子小穗中的硒含量和转录组反应进行了全面分析。
与未处理的对照相比，施用硒肥的谷子各组织中的硒含量显著升高。观察到硒酸盐依次在叶、茎和穗中运输和积累。转录组分析揭示了与硒代谢和运输相关的基因转录水平大幅上调，包括硫酸盐、磷酸盐和硝酸盐转运蛋白、ABC转运蛋白、抗氧化剂、植物激素信号传导和转录因子。这些基因表现出复杂的相互作用，既有协同作用也有拮抗作用，形成了一个调节硒酸盐运输机制的复杂网络。基因共表达网络分析突出了棕色模块中的三个转录因子和蓝绿色模块中的三个转运蛋白与硒的积累和运输显著相关。硫酸盐转运蛋白（SiSULTR1.2b和SiSULTR3.1a）、磷酸盐转运蛋白（PHT1.3）、硝酸盐转运蛋白1（NRT1.1B）、谷胱甘肽S-转移酶基因（GSTs）和ABC转运蛋白（ABCC13）的表达随着SeO积累而增加。转录因子MYB、WRKY和bHLH也被确定为参与硒积累的因素。
本研究为谷子中硒积累和运输的机制提供了初步见解。这些发现对富硒谷子的种植具有理论意义。
