Guimaraes Patricia Messenberg, Quintana Andressa Cunha, Mota Ana Paula Zotta, Berbert Pedro Souza, Ferreira Deziany da Silva, de Aguiar Matheus Nascimento, Pereira Bruna Medeiros, de Araújo Ana Claudia Guerra, Brasileiro Ana Cristina Miranda
Embrapa Genetic Resources and Biotechnology, Brasilia 70770-917, Brazil.
National Institute of Science and Technology (INCT Plant Stress Biotech), Brasilia 70770-917, Brazil.
Plants (Basel). 2022 Dec 13;11(24):3483. doi: 10.3390/plants11243483.
The association of both cell-surface PRRs (Pattern Recognition Receptors) and intracellular receptor NLRs (Nucleotide-Binding Leucine-Rich Repeat) in engineered plants have the potential to activate strong defenses against a broad range of pathogens. Here, we describe the identification, characterization, and in planta functional analysis of a novel truncated NLR (TNx) gene from the wild species (), with a protein structure lacking the C-terminal LRR (Leucine Rich Repeat) domain involved in pathogen perception. Overexpression of in tobacco plants led to a significant reduction in infection caused by , with a further reduction in pyramid lines containing an expansin-like B gene () potentially involved in defense priming. Transcription analysis of tobacco transgenic lines revealed induction of hormone defense pathways (SA; JA-ET) and PRs (Pathogenesis-Related proteins) production. The strong upregulation of the respiratory burst oxidase homolog D (RbohD) gene in the pyramid lines suggests its central role in mediating immune responses in plants co-expressing the two transgenes, with reactive oxygen species (ROS) production enhanced by cues leading to stronger defense response. Here, we demonstrate that the association of potential priming elicitors and truncated NLRs can produce a synergistic effect on fungal resistance, constituting a promising strategy for improved, non-specific resistance to plant pathogens.
工程植物中细胞表面模式识别受体（PRR）和细胞内受体核苷酸结合富含亮氨酸重复序列（NLR）的联合作用有潜力激活针对多种病原体的强大防御。在此，我们描述了从野生种（）中鉴定、表征和在植物体内对一个新型截短NLR（TNx）基因进行功能分析的过程，该基因的蛋白质结构缺少参与病原体识别的C端富含亮氨酸重复序列（LRR）结构域。在烟草植株中过表达该基因导致由引起的感染显著减少，在含有可能参与防御引发的类伸展蛋白B基因（）的聚合系中感染进一步减少。对烟草转基因系的转录分析揭示了激素防御途径（SA；JA - ET）的诱导和病程相关蛋白（PR）的产生。聚合系中呼吸爆发氧化酶同源物D（RbohD）基因的强烈上调表明其在介导共表达两个转基因的植物免疫反应中起核心作用，病原体信号导致活性氧（ROS）产生增加，从而引发更强的防御反应。在此，我们证明潜在的引发激发子和截短NLR的联合作用可对真菌抗性产生协同效应，构成一种有望提高植物对病原体非特异性抗性的策略。
