英国约翰·英纳斯中心Myriam Charpentier团队发现，自激活CNGC15可增强豆科植物和小麦的根系内共生能力。相关论文于2025年1月15日发表在《自然》杂志上。

研究人员发现了一种自激活CNGC15突变体，它能产生自发的低频钙（Ca²⁺）波动。CNGC15通过其螺旋1的门控机制产生核Ca²⁺振荡，而DOESN'T MAKE INFECTIONS1（DMI1）则作为起搏器调控振荡的频率。研究证明，共生诱导的核Ca²⁺波动的特异性体现在其频率上。高频率激活内共生程序，而低频率则调节苯丙酮途径。

因此，能够产生这两种频率的自交型cngc15突变体增加了黄酮类化合物的产生，从而增强了AM、根瘤共生和养分获取能力。研究人员将这一性状转移到小麦上，结果田间种植小麦的AM定殖和养分获取能力增强。该研究提出了一种新策略，可促进田间内生共生，减少无机肥料的使用，同时维持植物生长。

据介绍，养分获取对维持生命至关重要。植物分别与丛枝菌根（AM）和固氮细菌建立有益的细胞内共生关系，以克服土壤养分稀缺的问题和利用大气中的双氮气体。启动这些根内共生需要共生体诱导的根细胞核Ca²⁺浓度波动。目前仍不清楚核定位离子通道、环核苷酸门控通道（CNGC）15和DMI1是如何调控特定共生菌诱导的核Ca²⁺波动的。

附：英文原文

Title: Autoactive CNGC15 enhances root endosymbiosis in legume and wheat

Author: Cook, Nicola M., Gobbato, Giulia, Jacott, Catherine N., Marchal, Clemence, Hsieh, Chen Yun, Lam, Anson Ho Ching, Simmonds, James, del Cerro, Pablo, Gomez, Pilar Navarro, Rodney, Clemence, Cruz-Mireles, Neftaly, Uauy, Cristobal, Haerty, Wilfried, Lawson, David M., Charpentier, Myriam

Issue&Volume: 2025-01-15

Abstract: Nutrient acquisition is crucial for sustaining life. Plants develop beneficial intracellular partnerships with arbuscular mycorrhiza (AM) and nitrogen-fixing bacteria to surmount the scarcity of soil nutrients and tap into atmospheric dinitrogen, respectively1,2. Initiation of these root endosymbioses requires symbiont-induced oscillations in nuclear calcium (Ca2+) concentrations in root cells3. How the nuclear-localized ion channels, cyclic nucleotide-gated channel (CNGC) 15 and DOESN’T MAKE INFECTIONS1 (DMI1)4 are coordinated to specify symbiotic-induced nuclear Ca2+ oscillations remains unknown. Here we discovered an autoactive CNGC15 mutant that generates spontaneous low-frequency Ca2+ oscillations. While CNGC15 produces nuclear Ca2+ oscillations via a gating mechanism involving its helix 1, DMI1 acts as a pacemaker to specify the frequency of the oscillations. We demonstrate that the specificity of symbiotic-induced nuclear Ca2+ oscillations is encoded in its frequency. A high frequency activates endosymbiosis programmes, whereas a low frequency modulates phenylpropanoid pathways. Consequently, the autoactive cngc15 mutant, which is capable of generating both frequencies, has increased flavonoids that enhance AM, root nodule symbiosis and nutrient acquisition. We transferred this trait to wheat, resulting in field-grown wheat with increased AM colonization and nutrient acquisition. Our findings reveal a new strategy to boost endosymbiosis in the field and reduce inorganic fertilizer use while sustaining plant growth.

DOI: 10.1038/s41586-024-08424-7

Source: https://www.nature.com/articles/s41586-024-08424-7