Panax notoginseng (Burkill) F. H. Chen ex C. H. increasingly entered into people's daily life, but its quality has been greatly affected in recent years. Panax notoginseng is one of the representatives of the ginseng plant of Araliaceae, which is an important and precious local medicinal material in China. Basic helix–loop–helix transcription factors play an irreplaceable position in the life of plants and have obvious reactions to stresses. However, studies on the growth and resistance of P. notoginseng basic helix–loop–helixs under Nitrogen stress have not been extensively explored. In this paper, the 126 P. notoginseng basic helix–loop–helixs were analyzed by virtue of their chromosomal localization. The 98 genes were located on 12 chromosomes irregularly. In addition, collinearity events were mainly composed of fragment repetitions. Through phylogenetic analysis, the proteins were divided into 22 subgroups. The same set of genes had semblable motifs, gene structures, and cis-acting elements. Tissue specificity revealed expression levels of P. notoginseng basic helix–loop–helixs in roots, leaves, and flowers. Finally, some genes in the roots of P. notoginseng were differentially expressed under Nitrogen stress, especially P. notoginseng basic helix–loop–helix49 was significantly up-regulated. It can be used as a candidate gene which can resist Nitrogen stress. This study will not only lay the foundation to explore the functions of P. notoginseng basic helix–loop–helixs, but also be helpful for the further research of P. notoginseng.

三七（Burkill）FH Chen ex CH越来越多地进入人们的日常生活，但近年来其质量受到很大影响。三七是五加科人参植物的代表植物之一，是我国重要而珍贵的地方药材。碱性螺旋-环-螺旋转录因子在植物生命中发挥着不可替代的地位，对胁迫有明显的反应。然而，关于氮胁迫下三七碱性螺旋-环-螺旋的生长和抗性的研究尚未得到广泛探索。在本文中，126三七基本螺旋-环-螺旋通过它们的染色体定位进行分析。这98个基因不规则地分布在12条染色体上。此外，共线性事件主要由片段重复组成。通过系统发育分析，将蛋白质分为22个亚组。同一组基因具有相似的基序、基因结构和顺式作用元件。组织特异性揭示了三七基本螺旋-环-螺旋在根、叶和花中的表达水平。最后，三七根中的一些基因在氮胁迫下差异表达，尤其是三七基本螺旋-环-螺旋49显着上调。可作为抗氮胁迫的候选基因。本研究不仅为探索三七基本螺旋-环-螺旋的功能奠定基础，也有助于三七的进一步研究。