论文题目：The Puccinia striiformis effector Pst11215 manipulates mitochondria to suppress host immunity by promoting TaVDIP1-mediated ubiquitination of TaVDAC1
论文作者：Qinglin Pan, Yueyang Zhang, Yang Yang, Yixin Qiao, Yingrui Qian, Jinmian Wang, Xiaojie Wang, Zhensheng Kang*, Jie Liu*
论文摘要：
Mitochondria-induced cell death is closely correlated with plant immune responses against pathogens. However, the molecular mechanisms by which pathogens manipulate mitochondria to suppress host resistance remain poorly understood.
In this study, a haustorium-specific effector Pst11215 from the wheat stripe rust pathogen Puccinia striiformis f. sp. tritici (Pst) was characterized by host-induced gene silencing. The interaction partners regulated by Pst11215 were screened using the yeast two-hybrid system. In addition, Pst11215-mediated immune regulation modes were further determined. The results showed that Pst11215 was required for Pst virulence. Pst11215 interacted with the wheat voltage-dependent anion channel TaVDAC1, the negative regulator of wheat resistance to stripe rust, in mitochondria. Furthermore, the E3 ubiquitin ligase TaVDIP1 targeted and ubiquitinated TaVDAC1, which can be promoted by Pst11215. TaVDIP1 conferred enhanced wheat susceptibility to Pst by cooperating with TaVDAC1. Overexpression of TaVDIP1 reduced reactive oxygen species (ROS) accumulation and abnormal mitochondria. Our study revealed that Pst11215 functions as an important pathogenicity factor secreted to the host mitochondria to compromise wheat resistance to Pstpossibly by facilitating TaVDIP1-meidated ubiquitination of TaVDAC1, thereby protecting mitochondria from ROS-induced impairment. This research unveils a novel regulation mode of effectors hijacking host mitochondria to contribute to pathogen infection.
线粒体诱导的细胞死亡与植物对病原体的免疫反应密切相关。然而，病原体通过操纵寄主线粒体以抑制寄主抗病的分子机制知之甚少。在本研究中，利用寄主诱导的基因沉默对小麦条锈菌（Puccinia striiformis f.sp.tritici，Pst）的吸器特异性效应蛋白Pst11215进行了表征，通过酵母双杂交系统筛选出Pst11215的互作蛋白。此外，进一步确定了Pst11215介导的免疫调节模式。结果表明，Pst11215是条锈菌毒力所必需的，Pst11215在线粒体中与
小麦抗条锈病的负调节因子电压依赖性阴离子通道TaVDAC1相互作用。此外，E3泛素连接酶TaVDIP1靶向并泛素化TaVDAC1，且Pst112115可促进该泛素化过程。TaVDIP1与TaVDAC1的协同作用，增强了小麦对条锈菌的感病性。过表达TaVDIP1减少了活性氧（ROS）的积累和ROS造成的线粒体损伤。研究结果表明，Pst11215作为一个重要的致病因子被分泌到宿主线粒体中，通过促进TaVDIP1泛素化TaVDAC1，从而保护线粒体免受ROS诱导的损伤，降低小麦对条锈菌的抗性。本研究揭示了一种新的效应蛋白劫持宿主线粒体免疫以促进病原菌侵染的调控模式。
论文链接：http://doi.org/10.1111/nph.20146