Low nitrogen stress-induced transcriptome changes revealed the molecular response and tolerance characteristics in maintaining the C/N balance of sugar beet (Beta vulgaris L.)

作者：Jiajia Li, Xinyu Liu, Lingqing Xu, Wangsheng Li, Qi Yao, Xilong Yin, Qiuhong Wang, Wenbo Tan, Xing Wang, Dali Liu · 发表于：Frontiers in Plant Science · 年份：2023 · DOI：10.3389/fpls.2023.1164151 · 被引用次数：30 · 研究领域：Plant nutrient uptake and metabolism、Plant Stress Responses and Tolerance、Plant Micronutrient Interactions and Effects

Nitrogen (N) is an essential macronutrient for plants, acting as a common limiting factor for crop yield. The application of nitrogen fertilizer is related to the sustainable development of both crops and the environment. To further explore the molecular response of sugar beet under low nitrogen (LN) supply, transcriptome analysis was performed on the LN-tolerant germplasm ‘780016B/12 superior’. In total, 580 differentially expressed genes (DEGs) were identified in leaves, and 1,075 DEGs were identified in roots (log 2 |FC| ≥ 1; q value < 0.05). Gene Ontology (GO), protein−protein interaction (PPI), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses clarified the role and relationship of DEGs under LN stress. Most of the downregulated DEGs were closely related to “photosynthesis” and the metabolism of “photosynthesis-antenna proteins”, “carbon”, “nitrogen”, and “glutathione”, while the upregulated DEGs were involved in flavonoid and phenylalanine biosynthesis. For example, GLUDB (glutamate dehydrogenase B) was identified as a key downregulated gene, linking carbon, nitrogen, and glutamate metabolism. Thus, low nitrogen-tolerant sugar beet reduced energy expenditure mainly by reducing the synthesis of energy-consuming amino acids, which in turn improved tolerance to low nitrogen stress. The glutathione metabolism biosynthesis pathway was promoted to quench reactive oxygen species (ROS) and protect cells from oxidative damage. The expression levels of nitrogen a...