CREA, Research Centre for Olive, Fruit and Citrus Crops, Corso Savoia 190, 95024 Acireale, Italy.
Department of Agriculture, Food and Environment, University of Catania, Via Santa Sofia 98, 95123 Catania, Italy.
Int J Mol Sci. 2021 Jan 17;22(2):882. doi: 10.3390/ijms22020882.
Mal secco is one of the most severe diseases of citrus, caused by the necrotrophic fungus . With the main aim of identifying candidate genes involved in the response of citrus plants to "Mal secco", we performed a de novo transcriptome analysis of rough lemon seedlings subjected to inoculation of . The analysis of differential expressed genes (DEGs) highlighted a sharp response triggered by the pathogen as a total of 4986 significant DEGs (2865 genes up-regulated and 2121 down-regulated) have been revealed. The analysis of the most significantly enriched KEGG pathways indicated that a crucial role is played by genes involved in "Plant hormone signal transduction", "Phenylpropanoid biosynthesis", and "Carbon metabolism". The main findings of this work are that under fungus challenge, the rough lemon genes involved both in the light harvesting and the photosynthetic electron flow were significantly down-regulated, thus probably inducing a shortage of energy for cellular functions. Moreover, the systemic acquired resistance (SAR) was activated through the induced salicylic acid cascade. Interestingly, RPM1 interacting protein 4, an essential positive regulator of plant defense, and BIR2, which is a negative regulator of basal level of immunity, have been identified thus representing useful targets for molecular breeding.
马尔瑟克病是柑橘类水果最严重的疾病之一，由坏死型真菌引起。本研究的主要目的是鉴定与柑橘植物对“马尔瑟克病”反应相关的候选基因，我们对受接种的酸橙幼苗进行了从头转录组分析。差异表达基因（DEGs）的分析突显了病原体引发的强烈反应，共揭示了 4986 个显著的 DEGs（2865 个上调基因和 2121 个下调基因）。对最显著富集的 KEGG 途径的分析表明，参与“植物激素信号转导”、“苯丙烷生物合成”和“碳代谢”的基因起着关键作用。这项工作的主要发现是，在真菌的挑战下，与光捕获和光合作用电子流相关的酸橙基因显著下调，这可能导致细胞功能的能量短缺。此外，通过诱导水杨酸级联反应激活了系统性获得抗性（SAR）。有趣的是，鉴定到了 RPM1 互作蛋白 4，它是植物防御的必需正调控因子，和 BIR2，它是基础免疫的负调控因子，这两个因子代表了分子育种的有用靶标。
