Liu Jie, Yang Boming, Chen Xunji, Zhang Tengfei, Zhang Huairen, Du Yimo, Zhao Qian, Zhang Zhaogui, Cai Darun, Liu Juan, Chen Huabang, Zhao Li
Institute of Genetics and Developmental Biology, Key Laboratory of Seed Innovation, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Institute of Nuclear Technology and Biotechnology, Xinjiang Academy of Agriculture/Xinjiang Key Laboratory of Crop Biotechnology, Urumqi, Xinjiang 830091, China.
J Genet Genomics. 2025 Mar;52(3):334-345. doi: 10.1016/j.jgg.2024.12.015. Epub 2024 Dec 28.
Saline-alkali soil severely reduces the productivity of crops, including maize (Zea mays). Although several genes associated with saline-alkali tolerance have been identified in maize, the underlying regulatory mechanism remains elusive. Here, we report a direct link between colonization by arbuscular mycorrhizal fungi (AMF) and saline-alkali tolerance in maize. We identify s75, a natural maize mutant that cannot survive under moderate saline-alkali soil conditions or establish AM symbioses. The saline-alkali hypersensitive phenotype of s75 is caused by a 1340-bp deletion in Zm00001d033915, designated as ZmL75. This gene encodes a glycerol-3-phosphate acyltransferase localized in the endoplasmic reticulum, and is responsible for AMF colonization. ZmL75 expression levels in roots correspond with the root length colonization (RLC) rate during early vegetative development. Notably, the s75 mutant line shows a complete loss of AMF colonization, along with alterations in the diversity and structure of its root fungal microbiota. Conversely, overexpression of ZmL75 increases the RLC rate and enhances tolerance to saline-alkali soil conditions. These results suggest that ZmL75 is required for symbiosis with AMF, which directly improves saline-alkali tolerance. Our findings provide insights into maize-AMF interactions and offer a potential strategy for maize improvement.
盐碱土严重降低了包括玉米（Zea mays）在内的作物的生产力。尽管在玉米中已经鉴定出了几个与盐碱耐受性相关的基因，但其潜在的调控机制仍然不清楚。在这里，我们报道了丛枝菌根真菌（AMF）的定殖与玉米盐碱耐受性之间的直接联系。我们鉴定出了s75，这是一个天然的玉米突变体，在中度盐碱土壤条件下无法存活，也不能建立AM共生关系。s75的盐碱超敏表型是由Zm00001d033915中一个1340bp的缺失引起的，该基因被命名为ZmL75。该基因编码一种定位于内质网的甘油-3-磷酸酰基转移酶，负责AMF的定殖。在营养生长早期，根中ZmL75的表达水平与根长度定殖（RLC）率相对应。值得注意的是，s75突变系显示出AMF定殖完全丧失，同时其根真菌微生物群的多样性和结构也发生了改变。相反，ZmL75的过表达增加了RLC率，并增强了对盐碱土壤条件的耐受性。这些结果表明，ZmL75是与AMF共生所必需的，它直接提高了盐碱耐受性。我们的研究结果为玉米与AMF的相互作用提供了见解，并为玉米改良提供了一种潜在的策略。
