Nutrient exchange in arbuscular mycorrhizal symbiosis from a thermodynamic point of view
Nutrient exchange in arbuscular mycorrhizal symbiosis from a thermodynamic point of view
复制标题
DOI：
10.1111/nph.15646
复制
发表时间：
2019-04-01
期刊：
影响因子：
9.4
通讯作者：
Gohlke, Holger
中科院分区：
文献类型：
--
作者：
Dreyer, Ingo;Spitz, Olivia;Gohlke, Holger
为了深入了解丛枝菌根（AM）共生系统中养分交换的动态过程，我们建立了植物-真菌界面双膜系统的数学模型，并对其动态过程进行了模拟。在计算细胞生物学实验中，我们测试了各种养分运输途径交换磷（P）/碳（C）/氮（N）源的能力。结果表明，我们得到了一个合理的模型。植物-真菌接触带养分交换动力学的独立和综合模型。预测的最佳转运体网络与之前在湿实验室实验中独立证实的转运体集相吻合，表明所有必需的转运体类型都已被发现。热力学分析表明，真菌通过质子偶联磷酸盐转运体而不是阴离子通道释放磷酸盐。最佳的运输途径，如阳离子通道或质子偶联共转运蛋白，穿梭营养物质一起通过膜的正电荷。只有在特殊情况下，通过扩散促进剂的电中性运输似乎是合理的。这里提出的热力学模型可以推广和适应其他形式的菌根，并打开大门，为未来的研究结合湿实验室实验与计算模拟，以获得更深入的了解所调查的现象。
To obtain insights into the dynamics of nutrient exchange in arbuscular mycorrhizal (AM) symbiosis, we modelled mathematically the two-membrane system at the plant-fungus interface and simulated its dynamics.In computational cell biology experiments, the full range of nutrient transport pathways was tested for their ability to exchange phosphorus (P)/carbon (C)/nitrogen (N) sources.As a result, we obtained a thermodynamically justified, independent and comprehensive model of the dynamics of the nutrient exchange at the plant-fungus contact zone. The predicted optimal transporter network coincides with the transporter set independently confirmed in wet-laboratory experiments previously, indicating that all essential transporter types have been discovered.The thermodynamic analyses suggest that phosphate is released from the fungus via proton-coupled phosphate transporters rather than anion channels. Optimal transport pathways, such as cation channels or proton-coupled symporters, shuttle nutrients together with a positive charge across the membranes. Only in exceptional cases does electroneutral transport via diffusion facilitators appear to be plausible. The thermodynamic models presented here can be generalized and adapted to other forms of mycorrhiza and open the door for future studies combining wet-laboratory experiments with computational simulations to obtain a deeper understanding of the investigated phenomena.