Asselin Jo Ann E, Lin Jinshan, Perez-Quintero Alvaro L, Gentzel Irene, Majerczak Doris, Opiyo Stephen O, Zhao Wanying, Paek Seung-Mann, Kim Min Gab, Coplin David L, Blakeslee Joshua J, Mackey David
Department of Horticulture and Crop Science (J.E.A., J.L., A.L.P.-Q., Do.M., W.Z., J.J.B., Da.M.), Molecular and Cellular Imaging Center-Columbus, Ohio Agricultural Research and Development Center (J.L., S.O.O., J.J.B.), Translational Plant Sciences Graduate Program (I.G.), Center for Applied Plant Sciences (I.G., Da.M.), Department of Plant Pathology (D.L.C.), and Department of Molecular Genetics (Da.M.), Ohio State University, Columbus, Ohio 43210; andCollege of Pharmacy, Research Institute of Pharmaceutical Science, Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-751, Republic of Korea (S.-M.P., M.G.K.).
Department of Horticulture and Crop Science (J.E.A., J.L., A.L.P.-Q., Do.M., W.Z., J.J.B., Da.M.), Molecular and Cellular Imaging Center-Columbus, Ohio Agricultural Research and Development Center (J.L., S.O.O., J.J.B.), Translational Plant Sciences Graduate Program (I.G.), Center for Applied Plant Sciences (I.G., Da.M.), Department of Plant Pathology (D.L.C.), and Department of Molecular Genetics (Da.M.), Ohio State University, Columbus, Ohio 43210; andCollege of Pharmacy, Research Institute of Pharmaceutical Science, Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-751, Republic of Korea (S.-M.P., M.G.K.)
Plant Physiol. 2015 Mar;167(3):1117-35. doi: 10.1104/pp.114.253120. Epub 2015 Jan 29.
AvrE family type III effector proteins share the ability to suppress host defenses, induce disease-associated cell death, and promote bacterial growth. However, despite widespread contributions to numerous bacterial diseases in agriculturally important plants, the mode of action of these effectors remains largely unknown. WtsE is an AvrE family member required for the ability of Pantoea stewartii ssp. stewartii (Pnss) to proliferate efficiently and cause wilt and leaf blight symptoms in maize (Zea mays) plants. Notably, when WtsE is delivered by a heterologous system into the leaf cells of susceptible maize seedlings, it alone produces water-soaked disease symptoms reminiscent of those produced by Pnss. Thus, WtsE is a pathogenicity and virulence factor in maize, and an Escherichia coli heterologous delivery system can be used to study the activity of WtsE in isolation from other factors produced by Pnss. Transcriptional profiling of maize revealed the effects of WtsE, including induction of genes involved in secondary metabolism and suppression of genes involved in photosynthesis. Targeted metabolite quantification revealed that WtsE perturbs maize metabolism, including the induction of coumaroyl tyramine. The ability of mutant WtsE derivatives to elicit transcriptional and metabolic changes in susceptible maize seedlings correlated with their ability to promote disease. Furthermore, chemical inhibitors that block metabolic flux into the phenylpropanoid pathways targeted by WtsE also disrupted the pathogenicity and virulence activity of WtsE. While numerous metabolites produced downstream of the shikimate pathway are known to promote plant defense, our results indicate that misregulated induction of phenylpropanoid metabolism also can be used to promote pathogen virulence.
AvrE家族III型效应蛋白具有抑制宿主防御、诱导与疾病相关的细胞死亡以及促进细菌生长的能力。然而，尽管这些效应蛋白对农业重要植物中的多种细菌性疾病有广泛影响，但其作用方式仍 largely未知。WtsE是斯氏泛菌斯氏亚种（Pantoea stewartii ssp. stewartii，Pnss）在玉米（Zea mays）植株中高效增殖并引起枯萎和叶枯症状所必需的AvrE家族成员。值得注意的是，当通过异源系统将WtsE递送至易感玉米幼苗的叶细胞中时，它 alone 产生类似于Pnss产生的水渍状疾病症状。因此，WtsE是玉米中的致病性和毒力因子，并且大肠杆菌异源递送系统可用于单独研究WtsE的活性，而不受Pnss产生的其他因子的影响。玉米的转录谱分析揭示了WtsE的作用，包括诱导参与次生代谢的基因以及抑制参与光合作用的基因。靶向代谢物定量分析表明，WtsE扰乱玉米代谢，包括香豆酰酪胺的诱导。突变型WtsE衍生物在易感玉米幼苗中引发转录和代谢变化的能力与其促进疾病的能力相关。此外，阻断WtsE靶向的苯丙烷途径代谢通量的化学抑制剂也破坏了WtsE的致病性和毒力活性。虽然已知莽草酸途径下游产生的多种代谢物可促进植物防御，但我们的结果表明，苯丙烷代谢的失调诱导也可用于促进病原体毒力。
