State Key Laboratory of Crop Stress Biology for Arid Areas, College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China.
High Latitude Crops Institute of Shanxi Agriculture University, Datong, Shanxi, 037008, China.
Plant J. 2023 Jun;114(6):1443-1457. doi: 10.1111/tpj.16203. Epub 2023 Apr 5.
Nitrogen (N) is one of the most essential mineral elements for plants. Brassinosteroids (BRs) play key roles in plant growth and development. Emerging evidence indicates that BRs participate in the responses to nitrate deficiency. However, the precise molecular mechanism underlying the BR signaling pathway in regulating nitrate deficiency remains largely unknown. The transcription factor BES1 regulates the expression of many genes in response to BRs. Root length, nitrate uptake and N concentration of bes1-D mutants were higher than those of wild-type under nitrate deficiency. BES1 levels strongly increased under low nitrate conditions, especially in the non-phosphorylated (active) form. Furthermore, BES1 directly bound to the promoters of NRT2.1 and NRT2.2 to promote their expression under nitrate deficiency. Taken together, BES1 is a key mediator that links BR signaling under nitrate deficiency by modulating high affinity nitrate transporters in plants.
氮（N）是植物最基本的矿物质元素之一。油菜素内酯（BRs）在植物生长发育中起着关键作用。新出现的证据表明，BRs 参与了对硝酸盐缺乏的响应。然而，BR 信号通路在调节硝酸盐缺乏方面的确切分子机制在很大程度上仍然未知。转录因子 BES1 调节许多基因的表达以响应 BRs。bes1-D 突变体在硝酸盐缺乏下的根长、硝酸盐吸收和 N 浓度均高于野生型。BES1 水平在低硝酸盐条件下强烈增加，特别是在非磷酸化（活性）形式下。此外，BES1 直接结合到 NRT2.1 和 NRT2.2 的启动子上，以促进它们在硝酸盐缺乏下的表达。总之，BES1 是一种关键的中介物，通过调节植物中高亲和力硝酸盐转运体来连接硝酸盐缺乏下的 BR 信号。
