广州大学关跃峰团队发现，氮对氮酶活性的抑制涉及对大豆根瘤中细胞质转化酶的调节。该项研究成果于2024年6月29日在线发表在《遗传学报》上。

研究人员表示，豆科植物的共生固氮作用（SNF）受到土壤中无机氮的抑制。高氮对氮酶活性的抑制与碳在根瘤中的分配和代谢被剥夺有关。然而，其潜在的分子机制仍不清楚。

附：英文原文

Title: Nitrogen inhibition of nitrogenase activity involves the modulation of cytosolic invertase in soybean nodule

Author: Yuefeng Guan c

Issue&Volume: 2024/06/29

Abstract: Legume symbiotic nitrogen fixation (SNF) is suppressed by inorganic N in the soil. High N inhibition of nitrogenase activity is associated with the deprivation of carbon allocation and metabolism in nodules. However, the underlying molecular mechanisms remain unclear. Here, we identify GmCIN1 which encodes a cytosolic invertase, as a gateway for the N-tuning of sucrose utilization in nodules. GmCIN1 is enriched in mature soybean nodules and its expression is regulated by nitrogen status. The knockout of GmCIN1 using genome editing partially mimicks the inhibitory effects of N on nitrogenase activity and sugar content and the impact of high N on nodule transcriptomes. This indicates that GmCIN1 partially mediates the high N inhibition of nodule activity. Moreover, ChIP-qPCR and EMSA reveal that SNAP1/2 transcription factors directly bind to the GmCIN1 promoter. In addition, SNAP1/2 may be involved in the repression of GmCIN1 expression in mature nodules at high N concentrations. Our findings provide insights into the involvement of the transcriptional tuning of C metabolism genes by N-signaling modulators in the N-induced inhibition of nitrogenase activity.

DOI: 10.1016/j.jgg.2024.06.013

Source: https://www.sciencedirect.com/science/article/abs/pii/S1673852724001553