Glutamate synthase 1 is involved in iron-deficiency response and long-distance transportation in Arabidopsis

• 作者: Chunlin Chen Hong-Qing Ling Huilan Wu Man Cui Mengjun Gu Yaru Lu Yue Zhang
• 来源期刊: 植物学报（英文版）
• 年，卷（期）: 2020,（12）
• 所属期刊栏目: Plant-abiotic Interactions
• 页码范围: 1925-1941
• 页数: 17页
• 语种: 英文
• DOI: 10.1111/jipb.12985

摘要

Iron is an essential microelement for plant growth. After uptake from the soil, iron is chelated by ligands and translocated from roots to shoots for sub-sequent utilization. However, the number of ligands in-volved in iron chelation is unclear. In this study, we identified and demonstrated that GLU1, which encodes a ferredoxin-dependent glutamate synthase, was involved in iron homeostasis. First, the expression of GLU1 was strongly induced by iron deficiency condition. Second, lesion of GLU1 results in reduced transcription of many iron-deficiency-responsive genes in roots and shoots. The mutant plants revealed a decreased iron concentration in the shoots, and displayed severe leaf chlorosis under the condition of Fe limitation, compared to wild-type. Third, the product of GLU1, glutamate, could chelate iron in vivo and promote iron transportation. Last, we also found that supplementation of glutamate in the medium can alleviate cadmium toxicity in plants. Overall, our results provide evidence that GLU1 is involved in iron homeo-stasis through affecting glutamate synthesis under iron deficiency conditions in Arabidopsis.