Wang Xiangxiang, Wu He, Manzoor Nazer, Dongcheng Wenhua, Su Youbo, Liu Zhengjie, Lin Chun, Mao Zichao
College of Agronomy and Biotechnology, Yunnan Agricultural University (YNAU), Kunming 650201, China.
College of Resources and Environment, Yunnan Agricultural University, Kunming 650201, China.
Plants (Basel). 2024 Dec 17;13(24):3524. doi: 10.3390/plants13243524.
Quinoa () is an Andean allotetraploid pseudocereal crop with higher protein content and balanced amino acid composition in the seeds. Ammonium (NH), a direct source of organic nitrogen assimilation, mainly transported by specific transmembrane ammonium transporters (), plays important roles in the development, yield, and quality of crops. Many and their functions have been identified in major crops; however, no systematic analyses of and their regulatory networks, which is important to increase the yield and protein accumulation in the seeds of quinoa, have been performed to date. In this study, the were identified, followed by the quantification of the gene expression, while the regulatory networks were predicted based on weighted gene co-expression network analysis (WGCNA), with the putative transcriptional factors (TFs) having binding sites on the promoters of , nitrate transporters (), and glutamine-synthases (), as well as the putative TF expression being correlated with the phenotypes and activities of GSs, glutamate synthase (GOGAT), nitrite reductase (NiR), and nitrate reductase (NR) of quinoa roots. The results showed a total of 12 members of the family with varying expressions in different organs and in the same organs at different developmental stages. Complementation expression analyses in the triple mep1/2/3 mutant of yeast showed that except for , 11/12 restored the uptake of NH in the host yeast. was found to mainly locate on the cell membrane, while TFs (e.g., , , TFs, , , , , , and ) were predicted to be predominantly involved in the regulation, transportation, and assimilation of nitrogen. These results provide the functions of and their possible regulatory networks, which will lead to improved nitrogen use efficiency (NUE) in quinoa as well as other major crops.
藜麦（）是一种安第斯异源四倍体假谷物作物，其种子中蛋白质含量较高且氨基酸组成平衡。铵（NH）是有机氮同化的直接来源，主要由特定的跨膜铵转运蛋白（）运输，在作物的发育、产量和品质方面发挥着重要作用。在主要作物中已经鉴定出许多铵转运蛋白及其功能；然而，迄今为止，尚未对铵转运蛋白及其调控网络进行系统分析，而这对于提高藜麦种子的产量和蛋白质积累至关重要。在本研究中，鉴定了铵转运蛋白，随后对基因表达进行了定量，同时基于加权基因共表达网络分析（WGCNA）预测了调控网络，假定的转录因子（TFs）在铵转运蛋白、硝酸盐转运蛋白（）和谷氨酰胺合成酶（）的启动子上具有结合位点，并且假定的TF表达与藜麦根中谷氨酰胺合成酶（GSs）、谷氨酸合酶（GOGAT）、亚硝酸还原酶（NiR）和硝酸还原酶（NR）的表型及活性相关。结果表明，铵转运蛋白家族共有12个成员，在不同器官以及同一器官的不同发育阶段具有不同的表达。在酵母三突变体mep1/2/3中的互补表达分析表明，除了之外，12个铵转运蛋白中有11个恢复了宿主酵母对NH的吸收。发现主要定位于细胞膜上，而转录因子（例如，，，TFs，，，，，，和）预计主要参与氮的调控、运输和同化。这些结果提供了铵转运蛋白的功能及其可能的调控网络，这将提高藜麦以及其他主要作物的氮利用效率（NUE）。
