Complete RNA-seq data of EhVFT silencing strains.

Amebiasis is a parasitic infection of the human intestines, primarily caused by Entamoeba histolytica. Its pathogenesis relies on the environmental sensing-induced cytoskeletal remodeling as the basic mechanism for motility and tissue invasion. We identified and characterized an atypical Venus Fly-Trap (VFT) receptor protein, EhVFT (CL6EHI_096680). While it shares homology with the ligand-binding domain of class C GPCRs, it is phylogenetically related to the Periplasmic Binding Protein (PBP) superfamily. This protein is uniquely lacking a transmembrane domain. Instead, the glycosylphosphatidylinositol (GPI) anchor is responsible for its cell membrane localization. Removal of the GPI signal led to unexpected mitosomal localization, highlighting the importance of GPI modification in subcellular targeting. Functional studies revealed that EhVFT knockdown reduced parasite motility and phagocytosis of mammalian cells following the reduction of expression of actin cytoskeleton-related genes, including myosin II, villidin, and gelsolin. Our findings suggest that EhVFT plays a role in regulating downstream signaling linked to Entamoeba motility and phagocytosis. This study provides novel insights into an atypical VFT protein in E. histolytica, an area previously understudied.阿米巴病（Amebiasis）是一种人体肠道寄生虫感染性疾病，主要由溶组织内阿米巴（Entamoeba histolytica）引发。其发病机制以环境感应诱导的细胞骨架重塑作为运动能力与组织侵袭的核心基础。本研究鉴定并表征了一种非典型捕蝇夹（Venus Fly-Trap, VFT）受体蛋白EhVFT（CL6EHI_096680）。该蛋白虽与C类G蛋白偶联受体（GPCRs）的配体结合域具有同源性，但系统发育上隶属于周质结合蛋白（Periplasmic Binding Protein, PBP）超家族。该蛋白缺失跨膜结构域，而是通过糖基磷脂酰肌醇（GPI）锚定实现其细胞膜定位。去除GPI锚定信号后，该蛋白意外定位于纺锤剩体（mitosome），这凸显了GPI修饰在亚细胞靶向过程中的重要性。功能实验结果显示，敲低EhVFT的表达会导致肌动蛋白细胞骨架相关基因（包括肌球蛋白II、维利丁（villidin）与凝溶胶蛋白）的表达水平下调，进而削弱寄生虫的运动能力与对哺乳动物细胞的吞噬作用。本研究结果表明，EhVFT参与调控与溶组织内阿米巴运动及吞噬作用相关的下游信号通路。本研究为溶组织内阿米巴中这类此前研究较少的非典型VFT蛋白提供了全新的研究视角。