Abstract：
14-3-3 proteins play important roles in plant metabolism and stress response. Tomato 14-3-3 proteins, SlTFT4 and SlTFT7, serve as hubs of plant immunity and are targeted by some pathogen effectors. Ralstonia solanacearum with more than 70 type Ⅲ effectors (T3Es) is one of the most destructive plant pathogens. However, little is known on whether R. solanacearum T3Es target SlTFT4 and SlTFT7 and hence interfere with plant immunity. We first detected the associations of SlTFT4/SlTFT7 with R. solanacearum T3Es by luciferase complementation assay, and then confirmed the interactions by yeast two-hybrid approach. We demonstrated that 22 Ralstonia T3Es were associated with both SlTFT4 and SlTFT7, and five among them suppressed the hypersensitive response induced by MAPKKKα, a protein kinase which associated with SlTFT4/SlTFT7. We further demonstrated that suppression of MAPKKKα-induced HR and plant basal defense by the T3E RipAC depend on its association with 14-3-3 proteins. Our findings firstly demonstrate that R. solanacearum T3Es can manipulate plant immunity by targeting 14-3-3 proteins, SlTFT4 and SlTFT7, providing new insights into plant-R. solanacearum interactions.
摘要：
14-3-3蛋白在植物代谢和逆境胁迫反应中起重要作用。番茄14-3-3蛋白,SlTFT4和SlTFT7是植物免疫的枢纽，是一些病原体效应子的目标。具有70多个Ⅲ型效应物(T3Es)的青枯菌是最具破坏性的植物病原菌之一。然而,关于青枯菌T3Es是否靶向SlTFT4和SlTFT7并因此干扰植物免疫的情况知之甚少。我们首先通过荧光素酶互补试验检测了SlTFT4/SlTFT7与茄尾R.T3Es的关联，然后通过酵母双杂交方法证实了相互作用。我们证明了22种RalstoniaT3Es与SlTFT4和SlTFT7相关，其中5种抑制了MAPKKKα诱导的超敏反应，与SlTFT4/SlTFT7相关的蛋白激酶。我们进一步证明了T3ERipAC对MAPKKKα诱导的HR和植物基础防御的抑制取决于其与14-3-3蛋白的关联。我们的研究结果首先证明，青枯树T3Es可以通过靶向14-3-3蛋白来操纵植物免疫，SlTFT4和SlTFT7，提供了对plant-R的新见解。茄属植物相互作用。
