1 Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, U.S.A.
2 Department of Plant Sciences, University of Tennessee; and.
Mol Plant Microbe Interact. 2017 Jun;30(6):478-488. doi: 10.1094/MPMI-02-17-0031-R. Epub 2017 May 1.
The chloroplast-resident RNA helicase ISE2 (INCREASED SIZE EXCLUSION LIMIT2) can modulate the formation and distribution of plasmodesmata and intercellular trafficking. We have determined that ISE2 expression is induced by viral infection. Therefore, the responses of Nicotiana benthamiana plants with varying levels of ISE2 expression to infection by Tobacco mosaic virus and Turnip mosaic virus were examined. Surprisingly, increased or decreased ISE2 expression led to faster viral systemic spread and, in some cases, enhanced systemic necrosis. The contributions of RNA silencing and hormone-mediated immune responses to the increased viral susceptibility of these plants were assessed. In addition, Arabidopsis thaliana plants with increased ISE2 expression were found to be more susceptible to infection by the beet cyst nematode Heterodera schachtii. Our analyses provide intriguing insights into unexpected functional roles of a chloroplast protein in mediating plant-pathogen interactions. The possible roles of plasmodesmata in determining the outcomes of these interactions are also discussed.
定位于叶绿体的 RNA 解旋酶 ISE2（增加的胞间通道限制 2）可以调节胞间通道和细胞间运输的形成和分布。我们已经确定 ISE2 的表达是由病毒感染诱导的。因此，我们检测了具有不同 ISE2 表达水平的黄花烟植株对烟草花叶病毒和芜菁花叶病毒感染的反应。令人惊讶的是，增加或减少 ISE2 的表达会导致病毒更快地系统传播，并且在某些情况下，还会增强系统坏死。我们评估了 RNA 沉默和激素介导的免疫反应对这些植物增加的病毒易感性的贡献。此外，还发现过表达 ISE2 的拟南芥植物更容易感染甜菜胞囊线虫 Heterodera schachtii。我们的分析为叶绿体蛋白在介导植物-病原体相互作用方面的意外功能作用提供了有趣的见解。还讨论了胞间通道在决定这些相互作用结果中的可能作用。
