稻瘟病菌效应蛋白的分泌特征及其在水稻细胞中的转运

Secretory Characteristics of the Pyricularia oryzae Effectors and Their Intercellular Translocation in Rice Cells

许多病原菌能够通过分泌不同的效应蛋白以调控植物的防御以及胞内进程,从而助其有效入侵植物组织。稻瘟病菌的效应蛋白根据其不同的定位特点,被分为细胞质效应蛋白与质外体效应蛋白两类。在侵染过程中,细胞内的侵染菌丝被源于宿主植物的交界面菌丝膜(extrainvasive hyphal membrane, EIHM)包围,由EIHM与侵染菌丝细胞壁形成的质外体隔间是效应蛋白分泌的"必经通道"。此外,在稻瘟病菌侵染过程中会形成一个高度局部化的结构—活体营养表面复合体(biotrophic interfacial complex, BIC),它能够聚集由侵染菌丝分泌的细胞质效应蛋白。该文综述了稻瘟病菌效应蛋白的功能及其迁移过程,介绍了BIC的两个重要的形成阶段,阐明了不同效应蛋白的定位特点以及胞间转运的动态过程,揭示了效应蛋白分泌、转运至水稻细胞质以及在水稻细胞之间移动的分子机制。

In order to invade the plant effectively, many plant pathogens deliver various effector proteins into host cells to regulate plant defenses and intracellular processes. The effectors of the rice blast fungus are divided into two species according to the different localization features, cytoplasmic effectors and apoplastic effectors. In the infection process, the invasive hyphaes(IH) are surrounded by a plant-derived extrainvasive hyphal membrane(EIHM). The apoplastic compartment formed by EIHM and hyphal cell wall become to the necessary channel for effector to deliver. In addition, a highly localized structure, biotrophic interfacial complex(BIC) is formed in the infection process. The cytoplasmic effectors delivered by IH could be accumulated in BIC. In this review, the functions of effectors and their translocation in Pyricularia oryzae were illustrated. We introduced two important stages of the formation of BIC and illustrated the location characteristics and dynamic process of different effectors translocation. These reveal the molecular mechanisms of effectors secretion into BIC, translocation into rice cells, and cell-to-cell movement in rice.