MtBZR1 Plays an Important Role in Nodule Development in Medicago truncatula
MtBZR1 Plays an Important Role in Nodule Development in Medicago truncatula
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MtBZR1 在蒺藜苜蓿根瘤发育中发挥重要作用
DOI：
10.3390/ijms20122941
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发表时间：
2019-06-02
影响因子：
5.6
通讯作者：
Zhou, Chuanen
中科院分区：
文献类型：
--
作者：
Cui, Can;Wang, Hongfeng;Zhou, Chuanen
类维生素B1（BR）是植物生长发育所必需的激素。BR信号通路被广泛研究，其中BRASSINAZOLE RESISTANT 1（BZR 1）作为关键调节因子发挥作用。在这里，我们进行了功能研究的同源BZR 1在蒺藜苜蓿R108，其表达诱导根瘤接种苜蓿中华根瘤菌1021。我们鉴定了一个功能丧失突变体mtbzr1 - 1，并产生了35S：MtBZR 1转基因株系，以进一步在遗传水平上进行分析。在正常生长条件下，突变体和MtBZR 1过表达株系均未表现出明显的表型变化。继S.然而，与野生型相比，接种苜蓿1021后，MTBZR 1 - 1的地上部和根干质量降低，这是由于部分受损的根瘤发育造成的。转录组学分析确定了mtbzr1 - 1与野生型相比差异表达的1319个基因，其中许多基因与根瘤发育和次生代谢产物的生物合成有关。我们的研究结果证明了MtBZR 1在M. truncatula，揭示了BR在豆类根瘤菌共生中的潜在作用。
Brassinosteroid (BR) is an essential hormone in plant growth and development. The BR signaling pathway was extensively studied, in which BRASSINAZOLE RESISTANT 1 (BZR1) functions as a key regulator. Here, we carried out a functional study of the homolog of BZR1 in Medicago truncatula R108, whose expression was induced in nodules upon Sinorhizobium meliloti 1021 inoculation. We identified a loss-of-function mutant mtbzr1-1 and generated 35S:MtBZR1 transgenic lines for further analysis at the genetic level. Both the mutant and the overexpression lines of MtBZR1 showed no obvious phenotypic changes under normal growth conditions. After S. meliloti 1021 inoculation, however, the shoot and root dry mass was reduced in mtbzr1-1 compared with the wild type, caused by partially impaired nodule development. The transcriptomic analysis identified 1319 differentially expressed genes in mtbzr1-1 compared with wild type, many of which are involved in nodule development and secondary metabolite biosynthesis. Our results demonstrate the role of MtBZR1 in nodule development in M. truncatula, shedding light on the potential role of BR in legume–rhizobium symbiosis.