State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China.
The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China.
New Phytol. 2018 Jan;217(2):739-755. doi: 10.1111/nph.14842. Epub 2017 Oct 27.
Cerato-platanin proteins (CPs), which are secreted by filamentous fungi, are phytotoxic to host plants, but their functions have not been well defined to date. Here we characterized a CP (SsCP1) from the necrotrophic phytopathogen Sclerotinia sclerotiorum. Sscp1 transcripts accumulated during plant infection, and deletion of Sscp1 significantly reduced virulence. SsCP1 could induce significant cell death when expressed in Nicotiana benthamiana. Using yeast two-hybrid, GST pull-down, co-immunoprecipitation and bimolecular florescence complementation, we found that SsCP1 interacts with PR1 in the apoplast to facilitate infection by S. sclerotiorum. Overexpressing PR1 enhanced resistance to the wild-type strain, but not to the Sscp1 knockout strain of S. sclerotiorum. Sscp1-expressing transgenic plants showed increased concentrations of salicylic acid (SA) and higher levels of resistance to several plant pathogens (namely Botrytis cinerea, Alternaria brassicicola and Golovinomyces orontii). Our results suggest that SsCP1 is important for virulence of S. sclerotiorum and that it can be recognized by plants to trigger plant defense responses. Our results also suggest that the SA signaling pathway is involved in CP-mediated plant defense .
角担菌素蛋白（CPs）由丝状真菌分泌，对宿主植物具有植物毒性，但它们的功能尚未得到很好的定义。在这里，我们对坏死性植物病原菌核盘菌的一个 CP（SsCP1）进行了表征。SsCP1 转录本在植物感染过程中积累，并且 Sscp1 的缺失显著降低了毒力。SsCP1 在本氏烟中表达时可诱导显著的细胞死亡。通过酵母双杂交、GST 下拉、共免疫沉淀和双分子荧光互补实验，我们发现 SsCP1 在质外体中与 PR1 相互作用，以促进核盘菌的侵染。过表达 PR1 增强了对野生型菌株的抗性，但对核盘菌 Sscp1 敲除菌株没有增强抗性。表达 Sscp1 的转基因植物表现出水杨酸（SA）浓度增加和对几种植物病原体（即灰葡萄孢、芸薹生链格孢和禾谷多黏菌）的抗性增强。我们的结果表明，SsCP1 对核盘菌的毒力很重要，它可以被植物识别，从而触发植物防御反应。我们的结果还表明，SA 信号通路参与了 CP 介导的植物防御。
