Ammonium Secretion During Colletotrichum coccodes Infection Modulates Salicylic and Jasmonic Acid Pathways of Ripe and Unripe Tomato Fruit
Ammonium Secretion During Colletotrichum coccodes Infection Modulates Salicylic and Jasmonic Acid Pathways of Ripe and Unripe Tomato Fruit
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DOI：
10.1094/mpmi-01-11-0020
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发表时间：
2012-01-01
影响因子：
3.5
通讯作者：
Prusky, Dov
中科院分区：
文献类型：
--
作者：
Alkan, Noam;Fluhr, Robert;Prusky, Dov
采后病原菌球状炭疽菌在未成熟果实侵染后仍处于静止状态。然而，在果实成熟期间，病原菌呈现出一种坏死性的生活方式，迅速在组织中定居。球菌在寄主组织的萌发和定植过程中分泌铵，从而诱导寄主程序性细胞死亡。我们通过分析受感染和氨处理的水果组织与健康组织的转录组表达，进一步研究了氨在感染过程中的作用。分析发现，分别有82个和237个常见的上调和下调基因。对正常和转基因NADPH氧化酶反义植物中部分转录产物的定量逆转录聚合酶链式反应分析表明，它们的表达是NADPH氧化酶依赖的。普通上调基因表现为水杨酸(SA)依赖基因和生物胁迫相关基因的过度表达。下调的基因显示茉莉酸(JA)依赖基因的过度表达。果树直接使用水杨酸可促进球状念珠菌的坏死性定殖，而茉莉酸则延缓了定殖率。重要的是，绿色水果和红色水果表现出相似的基因表达模式，尽管只有红色水果对定殖敏感。因此，绿色水果对球菌定植的抗性很可能是由于其他因素造成的。
The postharvest pathogens Colletotrichum coccodes remains quiescent after infection of unripe fruit. However, during fruit ripening, the pathogen assumes a necrotrophic life style, rapidly colonizing the tissue. C. coccodes secretes ammonium during germination and colonization of host tissue that induces host programmed cell death. We further examined the role of ammonia in the infection process by analyzing transcriptome expression from infected and ammonia-treated fruit tissue compared with healthy tissue. The analysis revealed 82 and 237 common upregulated and downregulated genes, respectively. Quantitative reverse-transcriptase polymerase chain reaction analysis of select transcripts in normal and transgenic NADPH oxidase antisense plants revealed that their expression was NADPH oxidase dependent. Common-upregulated genes showed overrepresentation of salicylic acid (SA)-dependent genes as well as genes related to biotic stress. The downregulated genes showed overrepresentation of jasmonic acid (JA)-dependent genes. Indeed, direct application of SA to the fruit enhanced C. coccodes necrotrophic colonization, whereas the application of JA delayed colonization. Importantly, green fruit and red fruit displayed similar gene expression patterns although only red fruit is susceptible to colonization. Thus, it is likely that the resistance of green fruit to C. coccodes colonization is due to additional factors.