研究人员确定了两个大豆（Glycine max）含胱硫醚β合成酶域的蛋白质，即结核AMP传感器1（GmNAS1）和NAS1相关蛋白1（GmNAP1）。在高根瘤能量状态下，GmNAS1和GmNAP1形成同源二聚体，与线粒体上的核因子-Y C（NF-YC）亚单位（GmNFYC10a）相互作用，减少其核积累。较少的核GmNFYC10a导致参与丙酮酸生产的糖酵解基因表达降低，从而调节磷酸烯醇丙酮酸的分配，有利于固氮。对这些途径的深入了解可能有助于设计具有改善碳利用、固氮和生长的豆科作物。
据介绍，根瘤中的豆科植物-根瘤菌共生体固定氮，以满足植物的氮需求。根瘤对能量的需求被认为决定了固氮率。这种能量状态是如何被感知以调节固氮作用的，目前尚不清楚。
附：英文原文
Title: Phosphoenolpyruvate reallocation links nitrogen fixation rates to root nodule energy state
Author: Xiaolong Ke, Han Xiao, Yaqi Peng, Jing Wang, Qi Lv, Xuelu Wang
Issue&Volume: 2022-12-02
Abstract: Legume-rhizobium symbiosis in root nodules fixes nitrogen to satisfy the plant’s nitrogen demands. The nodules’ demand for energy is thought to determine nitrogen fixation rates. How this energy state is sensed to modulate nitrogen fixation is unknown. Here, we identified two soybean (Glycine max) cystathionine β-synthase domain–containing proteins, nodule AMP sensor 1 (GmNAS1) and NAS1-associated protein 1 (GmNAP1). In the high–nodule energy state, GmNAS1 and GmNAP1 form homodimers that interact with the nuclear factor-Y C (NF-YC) subunit (GmNFYC10a) on mitochondria and reduce its nuclear accumulation. Less nuclear GmNFYC10a leads to lower expression of glycolytic genes involved in pyruvate production, which modulates phosphoenolpyruvate allocation to favor nitrogen fixation. Insight into these pathways may help in the design of leguminous crops that have improved carbon use, nitrogen fixation, and growth.
DOI: abq8591
Source: https://www.science.org/doi/10.1126/science.abq8591