Zhang Yu, Wang Jie, Xiao Yong, Jiang Caihong, Cheng Lirui, Guo Shiping, Luo Chenggang, Wang Yuanying, Jia Haijiang
Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, 266101, People's Republic of China.
Sichuan Tobacco Company, Chengdu, 610000, People's Republic of China.
Mol Biol Rep. 2023 May;50(5):4395-4409. doi: 10.1007/s11033-023-08330-7. Epub 2023 Mar 27.
Tobacco brown spot disease is an important disease caused by Alternaria alternata that affects tobacco production and quality worldwide. Planting resistant varieties is the most economical and effective way to control this disease. However, the lack of understanding of the mechanism of tobacco resistance to tobacco brown spot has hindered progress in the breeding of resistant varieties.
In this study, differentially expressed proteins (DEPs), including 12 up-regulated and 11 down-regulated proteins, were screened using isobaric tags for relative and absolute quantification (iTRAQ) by comparing resistant and susceptible pools and analyzing the associated functions and metabolic pathways. Significantly up-regulated expression of the major latex-like protein gene 423 (MLP 423) was detected in both the resistant parent and the population pool. Bioinformatics analysis showed that the NbMLP423 cloned in Nicotiana benthamiana had a similar structure to the NtMLP423 in Nicotiana tabacum, and that expression of both genes respond rapidly to Alternaria alternata infection. NbMLP423 was then used to study the subcellular localization and expression in different tissues, followed by both silencing and the construction of an overexpression system for NbMLP423. The silenced plants demonstrated inhibited TBS resistance, while the overexpressed plants exhibited significantly enhanced resistance. Exogenous applications of plant hormones, such as salicylic acid, had a significant inducing effect on NbMLP423 expression.
Taken together, our results provide insights into the role of NbMLP423 in plants against tobacco brown spot infection and provide a foundation for obtaining resistant tobacco varieties through the construction of new candidate genes of the MLP subfamily.
烟草赤星病是由链格孢菌引起的一种重要病害，影响着全球烟草的生产和质量。种植抗病品种是防治该病最经济有效的方法。然而，对烟草抗赤星病机制的缺乏了解阻碍了抗病品种选育工作的进展。
在本研究中，通过比较抗病和感病混合群体，利用相对和绝对定量的等压标签（iTRAQ）筛选出差异表达蛋白（DEP），包括12个上调蛋白和11个下调蛋白，并分析了相关功能和代谢途径。在抗病亲本和群体库中均检测到主要乳胶样蛋白基因423（MLP 423）显著上调表达。生物信息学分析表明，在本氏烟草中克隆的NbMLP423与烟草中的NtMLP423结构相似，且两个基因的表达均对链格孢菌感染有快速响应。随后利用NbMLP423研究其亚细胞定位及在不同组织中的表达，接着对NbMLP423进行沉默和过表达系统构建。沉默植株表现出对烟草赤星病抗性的抑制，而过表达植株表现出显著增强的抗性。水杨酸等植物激素的外源施用对NbMLP423表达有显著诱导作用。
综上所述，我们的研究结果揭示了NbMLP423在植物抵抗烟草赤星病感染中的作用，为通过构建MLP亚家族新候选基因获得抗病烟草品种奠定了基础。
