The soil-born vascular disease Verticillium wilt, which is caused by fungal pathogen Verticillium dahliae, is a devastating disease of cotton worldwide. In the last decade, a large number of genes have been found to participate in cotton-V. dahliae interactions, but the detailed mechanisms of cotton resistance to V. dahliae remain unclear. Here, we functionally characterized MPK3, a MAPK gene from cotton. MPK3 was induced in the roots of both resistant and susceptible cotton cultivars by V. dahliae inoculation. Transgenic cotton and tobacco with constitutively higher GbMPK3 expression conferred higher V. dahliae susceptibility, while MPK3 knockdown in cotton has limited effect on cotton resistance to V. dahliae. Expression profiling revealed that SA-mediated defense pathway genes (WRKY70, PR1, and PR5) accumulated after V. dahliae inoculation in roots of both wild-type and transgenic cotton, and the expression levels of these genes were higher in GbMPK3-overexpressing plants than in wild-type plants, indicating that GbMPK3 upregulation may reduce plant resistance to V. dahliae through regulating salicylic acid signaling transduction.

中文翻译：

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GbMPK3过表达通过调节水杨酸信号增加棉花对大丽轮枝菌的敏感性

土壤传播的维管病黄萎病是由真菌病原体大丽轮枝菌引起的，是世界范围内棉花的毁灭性病害。在过去的十年中，已经发现大量基因参与了cotton-V。大丽花的相互作用，但棉花对大丽花抗性的详细机制仍不清楚。在这里，我们从功能上表征了 MPK3，一种来自棉花的 MAPK 基因。MPK3 在抗性和易感棉花品种的根中均被大丽花接种诱导。具有组成性更高 GbMPK3 表达的转基因棉花和烟草赋予了更高的大丽花弧菌易感性，而棉花中的 MPK3 敲低对棉花对大丽花弧菌的抗性影响有限。表达谱显示 SA 介导的防御途径基因（WRKY70、PR1 和 PR5）在 V.