Plant Molecular and Cellular Biology Program, Horticultural Sciences Department, PO Box 110690, University of Florida, Gainesville, FL 32611-0690, USA.
Mol Plant Pathol. 2005 Jan 1;6(1):79-83. doi: 10.1111/j.1364-3703.2004.00265.x.
SUMMARY The phytotoxin coronatine is a jasmonate mimic produced by Pseudomonas syringae pv. tomato (Pst). Coronatine acts as a virulence factor in Arabidopsis and mutants insensitive to coronatine are resistant to Pst and have higher levels of salicylic acid (SA). In this work we used the SA-deficient lines NahG and sid2-2 to determine if coronatine acts directly as a virulence factor or indirectly by SA suppression. Using coronatine-deficient Pst mutants we demonstrated that the lack of coronatine compromises Pst virulence in both wild-type and SA-deficient Arabidopsis. Thus, the action of coronatine is not due to SA suppression. Rather, SA-independent jasmonate-responses are the most likely mechanism for its action.
冠菌素是由丁香假单胞菌番茄致病变种（Pst）产生的茉莉酸类似物。在拟南芥中，冠菌素是一种毒力因子，而对冠菌素不敏感的突变体对 Pst 具有抗性，且水杨酸（SA）水平较高。在这项工作中，我们使用 SA 缺陷型 NahG 和 sid2-2 系来确定冠菌素是否直接作为毒力因子发挥作用，还是通过 SA 抑制间接发挥作用。使用冠菌素缺陷型 Pst 突变体，我们证明缺乏冠菌素会损害野生型和 SA 缺陷型拟南芥中 Pst 的毒力。因此，冠菌素的作用不是由于 SA 的抑制。相反，SA 不依赖的茉莉酸反应可能是其作用的最可能机制。
