Fu, Y. F. Zhang, Z. W. Yang, X. Y. Wang, C. Q. Lan, T. Tang, X. Y. Yuan, S. text xx 9999 monographic und

electronic

Nitrate reductase (NR)is one of the key enzymes for plant nitrogen assimilation and root architecture remodeling. However, crosstalk between NR-mediated signaling and auxin-mediated root development in nitrogen-status responses has not been investigated in details before. In this study, root phenotype and auxin distribution in nia1/nia2 (nitrate reductase)double mutant and chl1-5 (nitrate transporter NRT1.1)mutant under different nitrogen availabilities were compared. The nia1/nia2 mutant showed very low expression levels of auxin biosynthetic/signaling genes and was insensitive to nitrogen changes. While the chl1-5 mutant showed a high NR activity with a high level of auxin in the meristematic zone and a weaker response to nitrogen changes, when compared with the wild-type plants. We firstly found that NR activity was roughly positive-correlated with the root auxin level, and there is a crosstalk between nitrate signaling and auxin signaling. The putative signaling pathways downstream of NR have been discussed. NITRATE REDUCTASE NITRATE TRANSPORTER NRT1.1 NITRATE SIGNALING ROOT ARCHITECTURE REMODELING AUXIN BIOSYNTHESIS AND TRANSPORT https://drive.google.com/file/d/1ALQzcnGE2KtUTmcyZuIp1CkF86z0m45T/view?usp=drivesdk https://drive.google.com/file/d/1ALQzcnGE2KtUTmcyZuIp1CkF86z0m45T/view?usp=drivesdk 250602 20260521091628.0