Nutrient-dependent regulation of symbiotic nitrogen fixation in legumes

Abstract

Mineral nutrients are essential for plant growth and development, playing a critical role in the mutualistic symbiosis between legumes and rhizobia. Legumes have evolved intricate signaling pathways that respond to various mineral nutrients, selectively activating genes involved in nodulation and nutrient uptake during symbiotic nitrogen fixation (SNF). Key minerals, including nitrogen, calcium, and phosphorus, are vital throughout the SNF process, influencing signal recognition, nodule formation, the regulation of nodule numbers, and the prevention of nodule early senescence. Here, we review recent advancements in nutrient-dependent regulation of root nodule symbiosis, focusing on the systemic autoregulation of nodulation in nitrate-dependent symbiosis, the roles of nodule inception-like proteins, and the function of essential nutrients and their associated transporters in legume symbiosis. Additionally, we discuss several key research areas that require further exploration to deepen our understanding of nutrient-dependent mechanisms in SNF.

Acknowledgments

This work was financially supported by the National Natural Science Foundation of China (No. 32301477 to Y.M.) and (No. 32370224 to G.R.).

Author contributions

M.Y.L. and X.C.B. prepared the manuscript including text and figures in this review. R.G.P. and L.J.Q. gave valuable discussion and instructions. All authors read and approved the manuscript.

Data availability

All data supporting the findings of this review are available within the article.

Conflict of interest statement

The authors declare that they have no conflict of interest.

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