Toxoplasma can reach distant organs, especially the brain, leading to a lifelong chronic phase. However, genes involved in related in vivo processes are currently unknown. Here, we use focused CRISPR libraries to identify Toxoplasma genes that affect in vivo fitness. We focus on TgWIP, whose deletion affects Toxoplasma dissemination to distant organs. We show that TgWIP is secreted into the host cell upon invasion and interacts with the host WAVE regulatory complex and SHP2 phosphatase, both of which regulate actin dynamics. TgWIP affects the morphology of dendritic cells and mediates the dissolution of podosomes, which dendritic cells use to adhere to extracellular matrix. TgWIP enhances the motility and transmigration of parasitized dendritic cells, likely explaining its effect on in vivo fitness. Our results provide a framework for systemic identification of Toxoplasma genes with in vivo effects at the site of infection or on dissemination to distant organs, including the brain.

中文翻译：

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体内CRISPR筛选将TgWIP鉴定为树突状细胞迁移的弓形体调节剂。

弓形虫可以到达遥远的器官，特别是大脑，导致终身的慢性期。但是，目前尚不清楚涉及相关体内过程的基因。在这里，我们使用聚焦的CRISPR文库来鉴定影响体内适应性的弓形虫基因。我们专注于TgWIP，其删除会影响弓形虫向远端器官的传播。我们显示，TgWIP入侵后会分泌到宿主细胞中，并与宿主WAVE调节复合物和SHP2磷酸酶相互作用，两者均调节肌动蛋白的动力学。TgWIP影响树突状细胞的形态，并介导足小体的溶解，树突状细胞用于附着在细胞外基质上。TgWIP增强了寄生的树突状细胞的运动性和转运能力，这可能解释了其对体内适应性的影响。