Zhao Li, Liao Zhiwen, Feng Liping, An Bang, He Chaozu, Wang Qiannan, Luo Hongli
School of Life Sciences, Hainan University, Haikou, China.
College of Tropical Corps, Hainan University, Haikou, China.
Front Microbiol. 2023 Feb 17;14:1129101. doi: 10.3389/fmicb.2023.1129101. eCollection 2023.
Fungal chitin, as a typical microorganism-associated molecular pattern (PAMP), was recognized by plant LysM-containing protein to induce immunity called pattern-triggered immunity (PTI). To successfully infect host plant, fungal pathogens secreted LysM-containing effectors to inhibit chitin-induced plant immunity. Filamentous fungus caused rubber tree anthracnose which resulted in serious loss of natural rubber production worldwide. However, little is known about the pathogenesis mediated by LysM effector of . In this study, we identified a two LysM-containing effector in and named as Cg2LysM. Cg2LysM was involved not only in conidiation, appressorium formation, invasion growth and the virulence to rubber tree, but also in melanin synthesis of . Moreover, Cg2LysM showed chitin-binding activity and suppression of chitin-triggered immunity of rubber tree such as ROS production and the expression of defense relative genes , , and . This work suggested that Cg2LysM effector facilitate infection of to rubber tree through affecting invasive structure and inhibiting chitin-triggered plant immunity.
真菌几丁质作为一种典型的微生物相关分子模式（PAMP），被植物中含赖氨酸基序（LysM）的蛋白识别，从而诱导名为模式触发免疫（PTI）的免疫反应。为了成功感染宿主植物，真菌病原体分泌含LysM的效应子来抑制几丁质诱导的植物免疫。丝状真菌引发橡胶树炭疽病，导致全球天然橡胶产量严重损失。然而，关于 中LysM效应子介导的致病机制知之甚少。在本研究中，我们在 中鉴定出两个含LysM的效应子，并将其命名为Cg2LysM。Cg2LysM不仅参与分生孢子形成、附着胞形成、侵入生长以及对橡胶树的毒力，还参与 中黑色素的合成。此外，Cg2LysM表现出几丁质结合活性，并抑制橡胶树几丁质触发的免疫反应，如活性氧（ROS）产生以及防御相关基因 、 、 和 的表达。这项工作表明，Cg2LysM效应子通过影响侵入结构和抑制几丁质触发的植物免疫来促进 对橡胶树的感染。
