Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
Mol Biol Cell. 2023 Sep 1;34(10):ar103. doi: 10.1091/mbc.E23-01-0022. Epub 2023 Aug 2.
, the causative agent of African sleeping sickness, uses its flagellum for movement, cell division, and signaling. The flagellum is anchored to the cell body membrane the flagellum attachment zone (FAZ), a complex of proteins, filaments, and microtubules that spans two membranes with elements on both flagellum and cell body sides. How FAZ components are carried into place to form this complex is poorly understood. Here, we show that the trypanosome-specific kinesin KIN-E is required for building the FAZ in bloodstream-form parasites. KIN-E is localized along the flagellum with a concentration at its distal tip. Depletion of KIN-E by RNAi rapidly inhibits flagellum attachment and leads to cell death. A detailed analysis reveals that KIN-E depletion phenotypes include failure in cytokinesis completion, kinetoplast DNA missegregation, and transport vesicle accumulation. Together with previously published results in procyclic form parasites, these data suggest KIN-E plays a critical role in FAZ assembly in .
引起非洲昏睡病的寄生虫，利用其鞭毛进行运动、细胞分裂和信号传递。鞭毛固定在细胞膜上——鞭毛附着区（FAZ），这个复杂的蛋白、纤维和微管复合物跨越两个细胞膜，在鞭毛和细胞体两侧都有元件。FAZ 成分如何被运送到适当的位置形成这个复合物，目前还知之甚少。在这里，我们表明，锥虫特异性驱动蛋白 KIN-E 是构建血流形式寄生虫 FAZ 所必需的。KIN-E 沿着鞭毛定位，在其远端尖端处浓度较高。通过 RNAi 耗尽 KIN-E 会迅速抑制鞭毛附着并导致细胞死亡。详细分析表明，KIN-E 耗尽表型包括胞质分裂完成失败、动基体 DNA 错误分离和运输囊泡积累。与先前在循环形式寄生虫中发表的结果一起，这些数据表明 KIN-E 在 中的 FAZ 组装中发挥着关键作用。
