Department of Agronomy, Iowa State University, Ames, IA, 50011, USA.
Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA.
Sci Rep. 2024 May 28;14(1):12253. doi: 10.1038/s41598-024-62332-4.
Overexpression of Glycine max disease resistant 1 (GmDR1) exhibits broad-spectrum resistance against Fusarium virguliforme, Heterodera glycines (soybean cyst nematode), Tetranychus urticae (Koch) (spider mites), and Aphis glycines Matsumura (soybean aphids) in soybean. To understand the mechanisms of broad-spectrum immunity mediated by GmDR1, the transcriptomes of a strong and a weak GmDR1-overexpressor following treatment with chitin, a pathogen- and pest-associated molecular pattern (PAMP) common to these organisms, were investigated. The strong and weak GmDR1-overexpressors exhibited altered expression of 6098 and 992 genes, respectively, as compared to the nontransgenic control following chitin treatment. However, only 192 chitin- and 115 buffer-responsive genes exhibited over two-fold changes in expression levels in both strong and weak GmDR1-overexpressors as compared to the control. MapMan analysis of the 192 chitin-responsive genes revealed 64 biotic stress-related genes, of which 53 were induced and 11 repressed as compared to the control. The 53 chitin-induced genes include nine genes that encode receptor kinases, 13 encode nucleotide-binding leucine-rich repeat (NLR) receptor proteins, seven encode WRKY transcription factors, four ethylene response factors, and three MYB-like transcription factors. Investigation of a subset of these genes revealed three receptor protein kinases, seven NLR proteins, and one WRKY transcription factor genes that are induced following F. virguliforme and H. glycines infection. The integral plasma membrane GmDR1 protein most likely recognizes PAMPs including chitin and activates transcription of genes encoding receptor kinases, NLR proteins and defense-related genes. GmDR1 could be a pattern recognition receptor that regulates the expression of several NLRs for expression of PAMP-triggered immunity and/or priming the effector triggered immunity.
大豆 Glycine max 抗病 1 基因（GmDR1）的过表达表现出对尖孢镰刀菌、大豆孢囊线虫、二斑叶螨和豆蚜的广谱抗性。为了了解 GmDR1 介导的广谱免疫机制，研究了强和弱 GmDR1 过表达系在几丁质处理后（一种与这些生物相关的病原体和害虫相关的分子模式（PAMP））的转录组。与非转基因对照相比，几丁质处理后，强和弱 GmDR1 过表达系分别有 6098 和 992 个基因的表达发生了改变。然而，只有 192 个几丁质和 115 个缓冲响应基因在强和弱 GmDR1 过表达系中的表达水平比对照高出两倍以上。对 192 个几丁质响应基因的 MapMan 分析显示，有 64 个与生物胁迫相关的基因，其中 53 个基因被诱导，11 个基因被抑制。与对照相比，这 53 个几丁质诱导基因包括 9 个编码受体激酶的基因、13 个编码核苷酸结合富含亮氨酸重复（NLR）受体蛋白的基因、7 个编码 WRKY 转录因子的基因、4 个乙烯反应因子和 3 个 MYB 样转录因子。对其中一些基因的研究表明，三个受体蛋白激酶、七个 NLR 蛋白和一个 WRKY 转录因子基因在尖孢镰刀菌和大豆孢囊线虫感染后被诱导。完整的质膜 GmDR1 蛋白很可能识别包括几丁质在内的 PAMPs，激活编码受体激酶、NLR 蛋白和防御相关基因的转录。GmDR1 可能是一种模式识别受体，它调节几个 NLR 的表达，以表达 PAMP 触发的免疫和/或引发效应物触发的免疫。
