Key Laboratory of Soybean Biology of Chinese Ministry of Education, Key Laboratory of Soybean Biology and Breeding/Genetics of Chinese Agriculture Ministry, College of Science, Northeast Agricultural University, Harbin, Heilongjiang Province, People's Republic of China.
Jilin Academy of Agricultural Sciences, Soybean Research Institute, Changchun, People's Republic of China.
Mol Plant Microbe Interact. 2020 Jun;33(6):798-807. doi: 10.1094/MPMI-01-20-0017-R. Epub 2020 May 7.
In soybean ()-rhizobium interactions, the type III secretion system (T3SS) of rhizobium plays a key role in regulating host specificity. However, the lack of information on the role of T3SS in signaling networks limits our understanding of symbiosis. Here, we conducted an RNA sequencing analysis of three soybean chromosome segment substituted lines, one female parent and two derived lines with different chromosome-substituted segments of wild soybean and opposite nodulation patterns. By analyzing chromosome-linked differentially expressed genes in the substituted segments and quantitative trait loci (QTL)-assisted selection in the substituted-segment region, genes that may respond to type III effectors to mediate plant immunity-related signaling were identified. To narrow down the number of candidate genes, QTL assistant was used to identify the candidate region consistent with the substituted segments. Furthermore, one candidate gene, , was identified in the substituted segment. To investigate the role of GmDRR1 in symbiosis establishment, overexpression and RNA interference soybean lines were constructed. The nodule number increased in the former compared with wild-type soybean. Additionally, the T3SS-regulated effectors appeared to interact with the GmDDR1 signaling pathway. This finding will allow the detection of T3SS-regulated effectors involved in legume-rhizobium interactions.
在大豆-根瘤菌相互作用中，根瘤菌的 III 型分泌系统（T3SS）在调节宿主特异性方面发挥着关键作用。然而，缺乏关于 T3SS 在信号网络中作用的信息限制了我们对共生的理解。在这里，我们对三个大豆染色体片段代换系（一个母本和两个具有不同野生大豆染色体代换片段和相反结瘤模式的衍生系）进行了 RNA 测序分析。通过分析代换片段中与染色体相连的差异表达基因和代换片段区域的数量性状位点（QTL）辅助选择，鉴定出可能对 III 型效应子作出反应以介导植物免疫相关信号的基因。为了缩小候选基因的数量，使用 QTL 辅助鉴定与代换片段一致的候选区域。此外，在代换片段中鉴定出一个候选基因 GmDRR1。为了研究 GmDRR1 在共生建立中的作用，构建了过表达和 RNA 干扰的大豆株系。与野生型大豆相比，前者的根瘤数增加。此外，T3SS 调节的效应子似乎与 GmDDR1 信号通路相互作用。这一发现将允许检测参与豆科植物-根瘤菌相互作用的 T3SS 调节效应子。
