Intracellular bacteria have evolved various strategies to evade host defense mechanisms. Remarkably, the obligately intracellular bacterium, Ehrlichia chaffeensis, hijacks host cell processes of the mononuclear phagocyte to evade host defenses through mechanisms executed in part by tandem repeat protein (TRP) effectors secreted by the type 1 secretion system. In the past decade, TRP120 has emerged as a model moonlighting effector, acting as a ligand mimetic, nucleomodulin and ubiquitin ligase. These defined functions illuminate the diverse roles TRP120 plays in exploiting and manipulating host cell processes, including cytoskeletal organization, vesicle trafficking, cell signaling, transcriptional regulation, post-translational modifications, autophagy and apoptosis. This review will focus on TRP effectors and their expanding roles in infection and provide perspective on Ehrlichia chaffeensis as an invaluable model organism for understanding infection strategies of obligately intracellular bacteria.

中文翻译：

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埃立克体 TRP 效应器：兼职、模仿和感染

细胞内细菌已经进化出各种策略来逃避宿主防御机制。值得注意的是，专性细胞内细菌，恰菲埃里希氏菌，通过部分由 1 型分泌系统分泌的串联重复蛋白 (TRP) 效应器执行的机制，劫持单核吞噬细胞的宿主细胞过程以逃避宿主防御。在过去的十年中，TRP120 已成为一种典型的兼职效应器，充当配体模拟物、核调节蛋白和泛素连接酶。这些定义的功能阐明了 TRP120 在利用和操纵宿主细胞过程中所起的不同作用，包括细胞骨架组织、囊泡运输、细胞信号传导、转录调控、翻译后修饰、自噬和细胞凋亡。